UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 20-F

(Mark One)

OR

For the fiscal year ended December 31, 2019

OR

For the transition period from      to      

OR

Date of event requiring this shell company report      

Commission file number 001-38205

ZAI LAB LIMITED

(Exact name of Registrant as specified in its charter)

N/A

(Translation of Registrant’s name into English)

Cayman Islands

(Jurisdiction of incorporation or organization)

4560 Jinke Road

Shanghai , China 201210

(Address of principal executive offices)

Samantha Du

Chief Executive Officer
Zai Lab Limited

4560 Jinke Road

Shanghai , China 201210

Telephone: + 86 21 6163 2588

(Name, telephone, email and/or facsimile number and address of Company contact person)

Securities registered or to be registered pursuant to Section 12(b) of the Act:

Securities registered or to be registered pursuant to Section 12(g) of the Act:

None

(Title of Class)

Securities for which there is a reporting obligation pursuant to Section 15(d) of the Act:

None

(Title of Class)

Indicate the number of outstanding shares of each of the issuer’s classes of capital or common stock as of the close of the period covered by the Annual Report:

68,375,511 ordinary shares were issued and outstanding as of December 31, 2019

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. ☒ Yes ☐ No

If this report is an annual or transition report, indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934. ☐ Yes ☒ No

Note—checking the box above will not relieve any registrant required to file reports pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 from their obligations under those sections.

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. ☒ Yes ☐ No

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). ☒ Yes ☐ No

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or an emerging growth company. See definition of “accelerated filer and large accelerated filer” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company that prepares its financial statements in accordance with U.S. GAAP, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards† pursuant to Section 13(a) of the Exchange Act.   ☐

† The term “new or revised financial accounting standard” refers to any update issued by the Financial Accounting Standards Board to its Accounting Standards Codification after April 5, 2012.

Indicate by check mark which basis of accounting the registrant has used to prepare the financial statements included in this filing:

If “Other” has been checked in response to the previous question, indicate by check mark which financial statement item the registrant has elected to follow. ☐ Item 17 ☐ Item 18

If this is an Annual Report, indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). ☐ Yes ☒ No

Zai Lab Limited

Table of Contents

Industry and Market Data

Although we are responsible for all disclosure contained in this Annual Report on Form 20-F, in some cases we have relied on certain market and industry data obtained from third-party sources that we believe to be reliable. Market estimates are calculated by using independent industry publications, government publications and third-party forecasts in conjunction with our assumptions about our markets. While we are not aware of any misstatements regarding any market, industry or similar data presented herein, such data involves risks and uncertainties and is subject to change based on various factors, including those discussed under the headings “Cautionary Statement Regarding Forward-Looking Statements” and “Item 3.D. Risk Factors” in this Annual Report on Form 20-F.

Trademarks and Service Marks

We own or have rights to trademarks and service marks for use in connection with the operation of our business, including, but not limited to, ZAI LAB and 再鼎医药. All other trademarks or service marks appearing in this Annual Report on Form 20-F that are not identified as marks owned by us are the property of their respective owners.

Solely for convenience, the trademarks, service marks and trade names referred to in this Annual Report on Form 20-F are listed without the ®, (TM) and (sm) symbols, but we will assert, to the fullest extent under applicable law, our applicable rights in these trademarks, service marks and trade names.

CAUTIONARY STATEMENT REGARDING FORWARD‑LOOKING STATEMENTS

This Annual Report on Form 20-F contains forward-looking statements. Forward-looking statements are neither historical facts nor assurances of future performance. Instead, they are based on our current beliefs, expectations and assumptions regarding the future of our business, future plans and strategies, our operational results and other future conditions. Forward-looking statements can be identified by words such as “anticipate,” “believe,” “estimate,” “expect,” “intend,” “may,” “plan,” “predict,” “project,” “seek,” “target,” “potential,” “will,” “would,” “could,” “should,” “continue,” “contemplate” and other similar expressions, although not all forward-looking statements contain these identifying words. These forward-looking statements include all matters that are not historical facts. They appear in a number of places throughout this Annual Report on Form 20-F and include statements regarding our intentions, beliefs or current expectations concerning, among other things, our results of operations, financial condition, liquidity, prospects, growth, strategies and the industry in which we operate.

By their nature, forward-looking statements involve risks and uncertainties because they relate to events and depend on circumstances that may or may not occur in the future. We believe that these risks and uncertainties include, but are not limited to, those described in the “Item 3.D. Risk Factors” section of this Annual Report on Form 20-F, which include, but are not limited to, the following:

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These factors should not be construed as exhaustive and should be read with the other cautionary statements in this Annual Report on Form 20-F.

Although we base these forward-looking statements on assumptions that we believe are reasonable when made, we caution you that forward-looking statements are not guarantees of future performance and that our actual results of operations, financial condition and liquidity, and the development of the industry in which we operate may differ materially from those made in or suggested by the forward-looking statements contained in this Annual Report on Form 20-F. In addition, even if our results of operations, financial condition and liquidity, and the development of the industry in which we operate, are consistent with the forward-looking statements contained in this Annual Report on Form 20-F, those results or developments may not be indicative of results or developments in subsequent periods.

Given these risks and uncertainties, you are cautioned not to place undue reliance on these forward-looking statements. Any forward-looking statement that we make in this Annual Report on Form 20-F speaks only as of the date of such statement, and we undertake no obligation to update any forward-looking statements or to publicly announce the results of any revisions to any of those statements to reflect future events or developments. Comparisons of results for current and any prior periods are not intended to express any future trends or indications of future performance, unless specifically expressed as such, and should only be viewed as historical data.

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PART I

ITEM 1.  IDENTITY OF DIRECTORS, SENIOR MANAGEMENT AND ADVISERS

Not applicable.

ITEM 2.  OFFER STATISTICS AND EXPECTED TIMETABLE

Not applicable.

ITEM 3.  KEY INFORMATION

Our Selected Consolidated Financial Data

The following selected consolidated statement of operations data for the years ended December 31, 2019, 2018 and 2017 and the selected balance sheet data as of December 31, 2019 and 2018 have been derived from our audited consolidated financial statements included elsewhere in this Annual Report on Form 20-F. Our historical results for any period are not necessarily indicative of results to be expected for any future period. The selected consolidated financial data should be read in conjunction with, and are qualified in their entirety by reference to, our audited consolidated financial statements and related notes and “Item 5. Operating and Financial Review and Prospects” below. Our consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles, or U.S. GAAP.

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Not applicable.

Not applicable.

Risks Related to Our Financial Position and Need for Additional Capital

We have incurred significant losses since our inception and anticipate that we will continue to incur losses in the future and may never achieve or maintain profitability.

The Hong Kong Department of Health approved ZEJULA in October 2018 and we launched ZEJULA in Hong Kong in December 2018. In June 2019, we received marketing authorization to commercialize ZEJULA in Macau for women with relapsed ovarian cancer. The China National Medical Products Administration, or NMPA, approved ZEJULA in December 2019 as a maintenance therapy for adult patients with recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer, who are in a complete or partial response to platinum-based chemotherapy and we launched ZEJULA in the People’s Republic of China, or PRC or China, in January 2020. In December 2018, we announced the launch of Optune (Tumor Treating Fields) for the treatment of glioblastoma multiforme, or GBM, in Hong Kong. Although we launched ZEJULA in China in January 2020 for recurrent ovarian cancer, in Macau in June 2019 for recurrent ovarian cancer, and in Hong Kong in December 2018 for adult patients with platinum-sensitive relapsed high grade serous epithelial ovarian cancer who are in a complete response or partial response to platinum-based chemotherapy and we launched Optune (Tumor Treating Fields) in Hong Kong in December 2018, it will take some time to attain profitability and we may never do so. We have also obtained the rights to commercialize many clinical-stage drug candidates. Investment in biopharmaceutical product development is highly speculative because it entails substantial upfront capital expenditures and significant risk that a drug candidate will fail to gain regulatory approval or become commercially viable. To date, we have financed our activities primarily through private placements, our initial public offering in September 2017 and multiple follow-on offerings. For the year ended December 31, 2019, we generated revenue of $13.0 million from product sales, and we continue to incur significant development and other expenses related to our ongoing operations. As a result, we are not profitable and have incurred losses in each period since our inception in 2013. For the years ended December 31, 2019 and 2018, we reported a net loss of $195.1 million and $139.1 million, respectively.

We expect to continue to incur losses in the foreseeable future, and we expect these losses to increase as we:

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To become and remain profitable, we must continue commercialization efforts of ZEJULA and Optune and develop and eventually commercialize other drug candidates with significant market potential. This will require us to be successful in a range of challenging activities, including manufacturing, marketing and selling approved products such as ZEJULA, Optune and other products for which we may obtain marketing approval as well as completing pre-clinical testing and clinical trials of and obtaining marketing approval for our clinical and pre-clinical stage drug candidates. We will also need to be successful in satisfying any post-marketing requirements with respect to all of our products and drug candidates. We may not succeed in any or all of these activities and, even if we do, we may never generate product revenues that are significant or large enough to achieve profitability. We may encounter unforeseen expenses, difficulties, complications, delays and other unknown factors that may adversely affect our business. The size of our future net losses will depend, in part, on the rate of future growth of our expenses and our ability to generate revenue. Even if we achieve profitability in the future, we may not be able to sustain profitability in subsequent periods. Our failure to become and remain profitable would decrease the value of our company and could impair our ability to raise capital, maintain our research and development efforts and commercialization efforts, expand our business or continue our operations. A decline in the value of our company also could cause you to lose all or part of your investment.

We will continue to require substantial additional funding for our drug development programs and for our commercialization efforts for ZEJULA, Optune and other products for which we may obtain regulatory approval, which may not be available on acceptable terms, or at all. If we are unable to raise capital on acceptable terms when needed, we could incur losses or be forced to delay, reduce or terminate such efforts.

To date, we have financed our activities primarily through private placements, our initial public offering in September 2017 and three rounds of follow-on offerings. In January 2020, we raised $280.6 million in net proceeds from our subsequent follow-on offering of 6,300,000 of our American depositary shares, or ADSs. As of April 2020, through these offerings, we have raised $958.6 million. Our operations have consumed substantial amounts of cash since inception. The net cash used in our operating activities was $191.0 million and $97.5 million for the years ended December 31, 2019 and 2018, respectively. We expect our expenses to increase significantly in connection with our ongoing activities, particularly as we continue to commercialize ZEJULA and Optune, research and develop our pre-clinical-stage drug candidates and initiate additional clinical trials of, and seek and/or expand regulatory approval for, ZEJULA, Optune and our other drug assets. In addition, if we obtain regulatory approval for any additional drug candidates, we expect to incur significant commercialization expenses related to product manufacturing, marketing, sales and distribution. In particular, if more of our drug candidates are approved, additional costs may be substantial as we may have to modify or increase the production capacity at our current manufacturing facilities or contract with third-party manufacturers. We have, and may continue to, incur expenses as we create additional infrastructure to support our operations. Accordingly, we will likely need to obtain substantial additional funding in connection with our continuing operations through public or private equity offerings, debt financing, collaborations or licensing arrangements or other sources. If we are unable to raise capital when needed or on acceptable terms, we could incur losses and be forced to delay, reduce or terminate our research and development programs or any future commercialization efforts.

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We believe our cash and cash equivalents and short-term investments as of December 31, 2019 will enable us to fund our operating expenses and capital expenditure requirements for at least the next 12 months. We have based this estimate on assumptions that may prove to be wrong, and we could use our capital resources sooner than we currently expect. Our future capital requirements will depend on many factors, including:

Raising additional capital or entering into certain other arrangements may cause dilution to our shareholders, restrict our operations or require us to relinquish rights to our technologies or drug candidates.

Identifying and acquiring rights to develop potential drug candidates, conducting pre-clinical testing and clinical trials and commercializing products for which we receive regulatory approval is a time-consuming, expensive and uncertain process that may take years to complete. Our near-term commercial revenue, if any, will be derived from sales of ZEJULA and Optune. Any additional commercial revenue, if any, will be derived from sales of drug candidates that we do not expect to be commercially available until we receive regulatory approval, if at all. We may never generate the necessary data or results required to obtain regulatory approval and achieve product sales of some of our drug candidates, and even if we obtain regulatory approval, our products may not achieve commercial success. Accordingly, we will need to continue to rely on additional financing to achieve our business objectives. Adequate additional financing may not be available to us on acceptable terms, or at all.

We may seek additional funding through a combination of equity offerings, debt financings, collaborations, licensing arrangements, strategic alliances and marketing or distribution arrangements. To the extent that we raise additional capital through the sale of equity or convertible debt securities, our shareholders’ ownership interest will be diluted, and the terms may include liquidation or other preferences that adversely affect rights of our security holders. The incurrence of additional indebtedness or the issuance of certain equity securities could result in increased fixed payment obligations and could also result in certain additional restrictive covenants, such as limitations on our ability to

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incur additional debt or issue additional equity, limitations on our ability to acquire or license intellectual property rights and other operating restrictions that could adversely impact our ability to conduct our business. In addition, issuance of additional equity securities, or the possibility of such issuance, may cause the market price of our ADSs to decline. In the event that we enter into collaborations or licensing arrangements to raise capital, we may be required to accept unfavorable terms, including relinquishing or licensing to a third party on unfavorable terms our rights to technologies or drug candidates that we otherwise would seek to develop or commercialize ourselves or potentially reserve for future potential arrangements when we might be able to achieve more favorable terms.

Risks Related to Our Business and Industry

Even though we have launched ZEJULA in China, Hong Kong and Macau and Optune (Tumor Treating Fields) in Hong Kong, we may never obtain approval of or commercialize Optune outside of Hong Kong and we may never obtain approval of ZEJULA for other indications outside of the regulatory approvals we have already obtained, which would limit our ability to realize its full market potential.

In order to market products in any given jurisdiction, we must comply with numerous and varying regulatory requirements of such jurisdiction regarding safety, efficacy and quality. The Hong Kong Department of Health approved ZEJULA in October 2018 and we launched ZEJULA in Hong Kong in December 2018. In June 2019, we received marketing authorization to commercialize ZEJULA in Macau for women with relapsed ovarian cancer. The NMPA approved ZEJULA in December 2019 as a maintenance therapy for adult patients with recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer, who are in a complete or partial response to platinum-based chemotherapy and we launched ZEJULA in China in January 2020. In December 2018, we announced the launch of Optune (Tumor Treating Fields) for the treatment of GBM in Hong Kong. The approval of Optune for commercialization in Hong Kong does not mean that the NMPA will approve Optune. The approval of ZEJULA for certain indications does not mean that the NMPA will approve ZEJULA for other indications. Approval procedures vary among jurisdictions and clinical trials conducted in one jurisdiction may not be accepted by regulatory authorities in other jurisdictions, and regulatory approval in one country does not mean that regulatory approval will be obtained in any other jurisdiction.

We are invested in the commercial success of ZEJULA and Optune and our ability to generate product revenues in the near future is highly dependent on the commercial success of ZEJULA in China and Hong Kong and Optune in Hong Kong.

A substantial portion of our time, resources and effort are focused on the commercialization of our approved product ZEJULA in China, Hong Kong, and Macau, and our approved product Optune in Hong Kong. Our ability to generate product revenues will depend heavily on the successful commercialization of ZEJULA in China, Hong Kong and Macau and Optune in Hong Kong. Our ability to successfully commercialize ZEJULA and Optune will depend on, among other things, our ability to:

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There are no guarantees that we will be successful in completing these tasks. In addition, we have invested, and will continue to invest, substantial financial and management resources to build out our commercial infrastructure and to recruit and train sufficient additional qualified marketing, sales and other personnel in support of our sales of ZEJULA and Optune.

Sales of ZEJULA and Optune may be slow or limited for a variety of reasons including competing therapies or safety issues. If ZEJULA or Optune is not successful in gaining broad commercial acceptance, our business would be harmed.

Any sales of ZEJULA and Optune will be dependent on several factors, including our and our partners’ ability to educate and increase physician awareness of the benefits, safety and cost-effectiveness of ZEJULA and Optune relative to competing therapies. The degree of market acceptance of ZEJULA and Optune among physicians, patients, healthcare payors and the medical community will depend on a number of factors, including:

For example, due to business interruptions to hospitals and treatment centers in China arising in connection with the outbreak of COVID-19, some patients have experienced difficulties in accessing hospital care and, as a result, our commercial team has had fewer opportunities to reach patients who could benefit from ZEJULA or Optune ( Tumor Treating Fields ). Although the outbreak of COVID-19 has largely been contained in China and we have experienced

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only minimal disruption to our commercialization of ZEJULA and Optune ( Tumor Treating Fields ), outbreaks may occur again and may result in similar business interruptions in the future.

We have a very limited operating history, which may make it difficult for you to evaluate the success of our business to date and to assess our future viability.

We commenced our operations in 2014. Our operations to date have been limited to organizing and staffing our company, identifying potential partnerships and drug candidates, acquiring product and technology rights, conducting research and development activities for our drug candidates and, more recently, commercializing products for which we have obtained regulatory approval. We have not yet demonstrated the ability to successfully complete large-scale, pivotal clinical trials. Additionally, we have limited experience in the sale, marketing or distribution of pharmaceutical and medical device products. Consequently, any predictions about our future success, performance or viability may not be as accurate as they could be if we had a longer operating history.

Our limited operating history, particularly in light of the rapidly evolving drug research and development industry in which we operate, may make it difficult to evaluate our current business and prospects for future performance. Our short history makes any assessment of our future performance or viability subject to significant uncertainty. We will encounter risks and difficulties frequently experienced by companies in rapidly evolving fields as we continue to expand our commercial activities. In addition, as a new business, we may be more likely to encounter unforeseen expenses, difficulties, complications and delays due to limited experience. If we do not address these risks and difficulties successfully, our business will suffer.

Many of our drug candidates are still in clinical development. If we are unable to obtain regulatory approval and ultimately commercialize these drug candidates or experience significant delays in doing so, our business, financial condition, results of operations and prospects may be materially adversely harmed.

Many of our drug candidates are in clinical development and various others are in pre-clinical development. Our ability to generate revenue from our drug candidates is dependent on receipt of regulatory approval and successful commercialization of such products, which may never occur. Each of our drug candidates will require additional pre-clinical and/or clinical development, regulatory approval in multiple jurisdictions, development of manufacturing supply and capacity, substantial investment and significant marketing efforts before we generate any revenue from product sales. The success of our drug candidates will depend on several factors, including the following:

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The success of our business is substantially dependent on our ability to successfully commercialize ZEJULA and Optune as well as complete the development of, maintain, expand or obtain regulatory approval for, and successfully commercialize our drug candidates in a timely manner.

We cannot commercialize drug candidates in China without first obtaining regulatory approval from the NMPA. Similarly, we cannot commercialize drug candidates in the United States or another jurisdiction outside of China without obtaining regulatory approval from the U.S. Food and Drug Administration, or FDA, or comparable foreign regulatory authorities. The process to develop, obtain regulatory approval for and commercialize drug candidates is long, complex and costly both inside and outside of China and approval may not be granted. Clinical trials conducted in one country may not be accepted by regulatory authorities in other countries, and obtaining regulatory approval in one country does not mean that regulatory approval will be obtained in any other country. Approval processes vary among countries and can involve additional product testing and validation and additional administrative review periods. Even after obtaining regulatory approval from the FDA and comparable foreign regulatory authorities, we would still need to seek approval in China and any other jurisdictions where we plan to market the product. For example, we will need to conduct clinical trials of each of our drug candidates in patients in China prior to seeking regulatory approval in China. Even if our drug candidates have successfully completed clinical trials outside of China, there is no assurance that clinical trials conducted with Chinese patients will be successful. Any safety issues, product recalls or other incidents related to products approved and marketed in other jurisdictions may impact approval of those products by the NMPA. If we are unable to obtain regulatory approval for our drug candidates in one or more jurisdictions, or any approval contains significant limitations, or are imposed on certain drug candidates, we may not be able to obtain sufficient funding or generate sufficient revenue to continue the commercialization of our products and the development of our drug candidates or any other drug candidate that we may in-license, acquire or develop in the future.

We may allocate our limited resources to pursue a particular product, drug candidate or indication and fail to capitalize on products, drug candidates or indications that may later prove to be more profitable or for which there is a greater likelihood of success.

Because we have limited financial and managerial resources, we must limit our licensing, research, development and commercialization programs to specific products and drug candidates that we identify for specific indications. As a result, we may forego or delay pursuit of opportunities with other products or drug candidates or for other indications that later prove to have greater commercial potential. Our resource allocation decisions may cause us to fail to capitalize on viable commercial drugs or profitable market opportunities. In addition, if we do not accurately evaluate the commercial potential or target market for a particular drug candidate, we may relinquish valuable rights to that drug candidate through collaboration, licensing or other royalty arrangements when it would have been more advantageous for us to retain sole development and commercialization rights to such drug candidate.

Our products and drug candidates are subject to extensive regulation, and we cannot give any assurance that any of our drug candidates will receive any, or that any of our products will receive any additional, regulatory approval or be successfully commercialized.

Our products and drug candidates and the activities associated with their development and commercialization, including their design, testing, manufacture, safety, efficacy, quality control, recordkeeping, labeling, packaging, storage, approval, advertising, promotion, sale, distribution, import and export are subject to comprehensive regulation by the NMPA, FDA and European Medicines Agency, or EMA, and other regulatory agencies in China and the United States and by comparable authorities in other countries. We are not permitted to market any of our products or drug candidates in China, the United States and other jurisdictions unless and until we receive regulatory approval from the NMPA, FDA and EMA and other comparable authorities, respectively. Securing regulatory approval requires the submission of extensive pre-clinical and clinical data and supporting information to the various regulatory authorities for each therapeutic indication to establish the product’s or drug candidate’s safety and efficacy. Securing regulatory approval may also require the submission of information about the product or drug manufacturing process to, and inspection of manufacturing facilities by, the relevant regulatory authority. Our products and drug candidates may not be effective, may be only moderately effective or may prove to have undesirable or unintended side effects, toxicities or other characteristics that may preclude our obtaining regulatory approval or prevent or limit commercial use. Although Optune was approved for commercialization in Hong Kong, the United States and the European Union, we cannot provide any

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assurance that we will ever obtain regulatory approval for Optune in China or for any of our other drug candidates in any jurisdiction or that any of our drug candidates will be successfully commercialized even if we receive regulatory approval.

The process of obtaining regulatory approvals in China, the United States and other countries is expensive, may take many years of additional clinical trials and can vary substantially based upon a variety of factors, including the type, complexity and novelty of the product or drug candidates involved. Changes in regulatory approval policies during the development period, changes in or the enactment of additional statutes or regulations, or changes in regulatory review for each submitted New Drug Application, or NDA, pre-market approval or equivalent application type, may cause delays in the approval or rejection of an application. The NMPA, FDA and EMA and comparable authorities in other countries have substantial discretion in the approval process and may refuse to accept any application or may decide that our data are insufficient for approval and require additional pre-clinical, clinical or other studies. Our products and drug candidates could be delayed in receiving, or fail to receive, regulatory approval for many reasons, including the following:

In addition, even if we were to obtain approval, regulatory authorities may revoke approval, may approve any of our products or drug candidates for fewer or more limited indications than we request, may monitor the price we intend to charge for our products or drugs, may grant approval contingent on the performance of costly post-marketing clinical trials, or may approve a product or drug candidate with a label that does not include the labeling claims necessary or desirable for the successful commercialization of that product or drug candidate. Any of the foregoing scenarios could materially harm the commercial prospects for our products or drug candidates.

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The pharmaceutical industry in China is highly regulated and such regulations are subject to change, which may affect the approval and commercialization of our drugs and drug candidates.

The pharmaceutical industry in China is subject to comprehensive government regulation and supervision, encompassing the approval, manufacturing, distribution, and marketing of new drugs. In recent years, the pharmaceutical regulatory framework in China has undergone significant changes, and we expect that the transformation will continue. For instance, in June 2019, the State Council promulgated the Regulation on the Administration of PRC Human Genetic Resources, which became effective in July 2019. The Regulation on the Administration of PRC Human Genetic Resources replaced the advance approval requirement for clinical studies involving the collection of patient human genetic resources with a record-filing process, except for those involving the export of patient human genetic resources out of China. In August 2019, the PRC Drug Administration Law was amended by the Standing Committee of the National People’s Congress, and became effective in December 2019. The new Drug Administration Law codifies the marketing authorization holder system and enhances the compliance standards throughout the product life cycle. In January 2020, the SAMR released the amended Administrative Measures for Supervision and Administration for Drug Registration, or the Drug Registration Measures Regulation, and the amended Measures for Supervision and Administration for Drug Manufacturing, or Drug Manufacturing Regulation, both of which will come into effect in July 2020. In April 2020, the NMPA and the NHC released the amended Good Clinical Practice for Pharmaceutical Product, or the Amended GCP, which will come into effect in July 2020. The amended Drug Registration Regulations omits the provisions that provide an administrative exclusivity of the new drug monitoring period up to five years. Detailed implementation rules on the Drug Registration Regulation and Drug Manufacturing Regulation are still pending, thus uncertainties exist as to whether other intellectual property protection systems, such as patent linkage and patent term extension, would be available.

Any changes or amendments with respect to government regulation and supervision of the pharmaceutical industry in China may result in uncertainties with respect to the interpretation and implementation of the relevant laws and regulations or adversely impact the development or commercialization of our drugs and drug candidates in China.

For further information regarding government regulation in China and other jurisdictions, see “Regulation—Government Regulation of Pharmaceutical Product Development and Approval,” “Regulation—Coverage and Reimbursement” and “Regulation—Other Healthcare Laws.”

If safety, efficacy, manufacturing or supply issues arise with any therapeutic that we use in combination with our products and drug candidates, we may be unable to market such products or drug candidate or may experience significant regulatory delays or supply shortages, and our business could be materially harmed.

We plan to develop certain of our products and drug candidates for use as a combination therapy. For example, GlaxoSmithKline, or GSK, is currently developing, and we also plan to develop, ZEJULA as both a monotherapy and in combination with any potential anti-VEGF or PD-1/PD-L1 treatments. However, we did not develop or obtain regulatory approval for, and we do not manufacture or sell, any anti-VEGF or PD-1/PD-L1 treatments or any other therapeutic we use in combination with our drug candidates. We may also seek to develop our drug candidates in combination with other therapeutics in the future.

If the NMPA, FDA or another regulatory agency revokes its approval of any anti-VEGF or PD-1/PD-L1 treatments or another therapeutic we use in combination with our drug candidates, we will not be able to market our drug candidates in combination with such revoked therapeutic. If safety or efficacy issues arise with these or other therapeutics that we seek to combine with our drug candidates in the future, we may experience significant regulatory delays, and we may be required to redesign or terminate the applicable clinical trials. In addition, if manufacturing or other issues result in a supply shortage of any anti-VEGF or PD-1/PD-L1 treatments or any other combination therapeutics, we may not be able to successfully commercialize ZEJULA on our current timeline or at all.

Even after obtaining regulatory approval for use in combination with any anti-VEGF or PD-1/PD-L1 treatments, as applicable, or another therapeutic, we would continue to be subject to the risk that the NMPA, FDA or another regulatory agency could revoke its approval of the combination therapeutic, or that safety, efficacy, manufacturing or supply issues could arise with one of these combination therapeutics. This could result in ZEJULA or one of our other products being removed from the market or being less successful commercially.

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Additionally, although we have not experienced material supply disruptions due to the outbreak of COVID-19, we cannot guarantee that we will not experience supply disruptions in the future due to COVID-19 or any other pandemic, epidemic or other public health crises, natural catastrophe or other disasters.

We face substantial competition, which may result in our competitors discovering, developing or commercializing drugs before or more successfully than we do, or developing products or therapies that are more advanced or effective than ours, which may adversely affect our financial condition and our ability to successfully market or commercialize our products and drug candidates.

The development and commercialization of new medical device products and drugs is highly competitive. We face competition with respect to our current products and drug candidates, and will face competition with respect to any drug candidates that we may seek to develop or commercialize in the future, from major pharmaceutical companies, specialty pharmaceutical companies, biotechnology companies and medical device companies worldwide. For example, there are a number of large pharmaceutical and biotechnology companies that currently market drugs or are pursuing the development of therapies in the field of poly ADP ribose polymerase, or PARP, inhibition to treat cancer. Some of these competitive drugs and therapies are based on scientific approaches that are the same as or similar to that of our drug candidates. Potential competitors also include academic institutions, government agencies and other public and private research organizations that conduct research, seek patent protection and establish collaborative arrangements for research, development, manufacturing and commercialization. Specifically, there are a large number of companies developing or marketing treatments for oncology, autoimmune and infectious diseases including many major pharmaceutical and biotechnology companies.

Many of the companies against which we are competing or against which we may compete in the future have significantly greater financial resources and expertise in research and development, manufacturing, pre-clinical testing, conducting clinical trials, obtaining regulatory approvals and marketing approved drugs than we do. Mergers and acquisitions in the pharmaceutical, biotechnology and diagnostic industries may result in even more resources being concentrated among a smaller number of our competitors. Smaller or early stage companies may also prove to be significant competitors, particularly through collaborative arrangements with large and established companies. These competitors also compete with us in recruiting and retaining qualified scientific and management personnel and establishing clinical trial sites and patient registration for clinical trials, as well as in acquiring technologies complementary to, or necessary for, our programs.

Our commercial opportunities could be reduced or eliminated if our competitors develop and commercialize products or drugs that are safer, more effective, have fewer or less severe side effects, are more convenient or are less expensive than products or drugs that we may develop. Our competitors also may obtain NMPA, FDA or other regulatory approval for their products or drugs more rapidly than we may obtain approval for ours, which could result in our competitors establishing a strong market position before we are able to enter the market. Additionally, technologies developed by our competitors may render our products or potential drug candidates uneconomical or obsolete, and we may not be successful in marketing our products or drug candidates against competitors.

In addition, as a result of the expiration or successful challenge of our patent rights, we could face more litigation with respect to the validity and/or scope of patents relating to our competitors’ products. The availability of our competitors’ products could limit the demand, and the price we are able to charge, for any products that we may develop and commercialize.

Clinical development involves a lengthy and expensive process with an uncertain outcome.

There is a risk of failure for each of our drug candidates. It is difficult to predict when or if any of our drug candidates will prove effective and safe in humans or will receive regulatory approval. Before obtaining regulatory approval from regulatory authorities for the sale of any drug candidate, our drug candidates must complete pre-clinical studies and then conduct extensive clinical trials to demonstrate the safety and efficacy of our drug candidates in humans. Clinical testing is expensive, difficult to design and implement, and can take many years to complete.

The outcomes of pre-clinical development testing and early clinical trials may not be predictive of the success of later clinical trials, and interim results of a clinical trial do not necessarily predict final results. Moreover, pre-clinical and clinical data are often susceptible to varying interpretations and analyses, and many companies that have believed their drug candidates performed satisfactorily in pre-clinical studies and clinical trials have nonetheless failed to obtain regulatory approval of their drug candidates. Future clinical trials of our drug candidates may not be successful. For

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example, brivanib (ZL-2301) failed to meet its primary endpoint of overall survival, or OS, noninferiority for brivanib (ZL-2301) versus sorafenib in Phase III trials in patients with HCC conducted by Bristol-Myers Squibb Company, or BMS, before we licensed the development rights from them. In addition, brivanib (ZL-2301) showed no difference when compared to placebo in the primary efficacy endpoint. Although we believe that brivanib (ZL-2301) has the potential to be an effective treatment for Chinese patients and merits further clinical trials patients, we cannot guarantee that our future clinical trials of brivanib (ZL-2301) in Chinese patients will be successful.

Commencement of clinical trials is subject to finalizing the trial design based on ongoing discussions with the NMPA, FDA and/or other regulatory authorities. The NMPA, FDA and other regulatory authorities could change their position on the acceptability of trial designs or clinical endpoints, which could require us to complete additional clinical trials or impose approval conditions that we do not currently expect. Successful completion of our clinical trials is a prerequisite to submitting an NDA (or analogous filing) to the NMPA, FDA and/or other regulatory authorities for each drug candidate and, consequently, the ultimate approval and commercial marketing of our drug candidates. We do not know whether the clinical trials for our drug candidates will begin or be completed on schedule, if at all.

We may incur additional costs or experience delays in completing pre-clinical or clinical trials, or ultimately be unable to complete the development and commercialization of our products and drug candidates.

We may experience delays in completing our pre-clinical or clinical trials, and numerous unforeseen events could arise during, or as a result of, future clinical trials, which could delay or prevent us from receiving regulatory approval, including:

We could encounter regulatory delays if a clinical trial is suspended or terminated by us or, as applicable, the IRBs or the ethics committee of the institutions in which such trials are being conducted, by the data safety monitoring

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board, which is an independent group of experts that is formed to monitor clinical trials while ongoing, or by the NMPA, FDA or other regulatory authorities. Such authorities may impose a suspension or termination due to a number of factors, including: a failure to conduct the clinical trial in accordance with regulatory requirements or the applicable clinical protocols, a failure to obtain the regulatory approval and/or complete record filings with respect to the collection, preservation, use and export of China's human genetic resources, inspection of the clinical trial operations or trial site by the NMPA, FDA or other regulatory authorities that results in the imposition of a clinical hold, unforeseen safety issues or adverse side effects, failure to demonstrate a benefit from using a drug, changes in governmental regulations or administrative actions or lack of adequate funding to continue the clinical trial. Many of the factors that cause a delay in the commencement or completion of clinical trials may also ultimately lead to the denial of regulatory approval of our drug candidates. Further, the NMPA, FDA or other regulatory authorities may disagree with our clinical trial design or our interpretation of data from clinical trials, or may change the requirements for approval even after it has reviewed and commented on the design for our clinical trials.

If we are required to conduct additional clinical trials or other testing of our products or drug candidates beyond those that are currently contemplated, if we are unable to successfully complete clinical trials of our products or drug candidates or other testing, if the results of these trials or tests are not positive or are only modestly positive or if there are safety concerns, we may:

Our product and drug development costs will also increase if we experience delays in testing or regulatory approvals. We do not know whether any of our clinical trials will begin as planned, will need to be restructured or will be completed on schedule, or at all. Significant pre-clinical study or clinical trial delays also could allow our competitors to bring products to market before we do and impair our ability to successfully commercialize our products and drug candidates and may harm our business and results of operations. Any delays in our clinical development programs may harm our business, financial condition and prospects significantly.

If we experience delays or difficulties in the enrollment of patients in clinical trials, the progress of such clinical trials and our receipt of necessary regulatory approvals could be delayed or prevented.

We may not be able to initiate or continue clinical trials for our products and drug candidates if we are unable to locate and enroll a sufficient number of eligible patients to participate in these trials as required by the NMPA, FDA or similar regulatory authorities. In particular, we have designed many of our clinical trials, and expect to design future trials, to include some patients with the applicable genomic mutation with a view to assessing possible early evidence of potential therapeutic effect. Genomically defined diseases, however, may have relatively low prevalence, and it may be difficult to identify patients with the applicable genomic mutation. The inability to enroll a sufficient number of patients with the applicable genomic alteration or that meet other applicable criteria for our clinical trials would result in significant delays and could require us to abandon one or more clinical trials altogether.

In addition, some of our competitors have ongoing clinical trials for products or drug candidates that treat the same indications as our products or drug candidates, and patients who would otherwise be eligible for our clinical trials may instead enroll in clinical trials of our competitors’ products or drug candidates.

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Patient enrollment may be affected by other factors including:

For example, we have experienced delays in the enrollment of patients in our clinical trials due to the outbreak of COVID-19. Although the outbreak of COVID-19 has largely been contained in China and we have experienced only minimal disruption to our planned clinical trials, outbreaks may occur again and may result in delays and interruptions to our clinical trials in the future. Additionally, our commercial partners and licensors have similarly experienced and may continue to experience delays in enrollment of patients to their clinical trials due to the outbreak of COVID-19 in their respective territories. Such delays may result in increased development costs for our products and drug candidates, which could cause the value of our company to decline and limit our ability to obtain additional financing.

Our products and drug candidates may cause undesirable side effects that could delay or prevent their regulatory approval, limit the commercial profile of an approved label, or result in significant negative consequences following regulatory approval, if any.

Undesirable side effects caused by our products or drug candidates could cause us to interrupt, delay or halt clinical trials or could cause regulatory authorities to interrupt, delay or halt our clinical trials and could result in a more restrictive label or the delay or denial of regulatory approval by the NMPA, FDA or other regulatory authorities. In particular, as is the case with all oncology products and drugs, it is likely that there may be side effects, such as fatigue, nausea and low blood cell levels, associated with the use of certain of our oncology products or drug candidates. For example, the known adverse events for ZEJULA include thrombocytopenia, anemia and neutropenia and for brivanib (ZL-2301), the known adverse events include hyponatremia, AST elevation, fatigue, hand-foot skin reaction and hypertension. The results of our products’ or drug candidates’ trials could reveal a high and unacceptable severity and prevalence of these or other side effects. In such an event, trials of our products or drug candidates could be suspended or terminated and the NMPA, FDA or comparable regulatory authorities could order us to cease further development of or deny approval of our products or drug candidates for any or all targeted indications. The drug-related side effects could affect patient recruitment or the ability of enrolled patients to complete the trial or result in potential product liability claims. Any of these occurrences may harm our business, financial condition and prospects significantly.

Additionally, our products and drug candidates could cause undesirable side effects related to off-target toxicity. For example, many of the currently approved PARP inhibitors have been associated with off-target toxicities. Many compounds that initially showed promise in early stage testing for treating cancer have later been found to cause side effects that prevented further development of the compound.

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Clinical trials assess a sample of the potential patient population. With a limited number of patients and duration of exposure, rare and severe side effects of our products or drug candidates may only be uncovered with a significantly larger number of patients exposed to the drug candidate. Even after a product or drug candidate receives regulatory approval, if we, our partners or others identify undesirable side effects caused by such drug candidates (or any other similar drugs) after such approval, a number of potentially significant negative consequences could result, including:

Any of these events could prevent us from achieving or maintaining market acceptance of the affected products or drug candidates and could substantially increase the costs of commercializing our products and drug candidates, if approved, and significantly impact our ability to successfully commercialize our products and drug candidates and generate revenue.

If we are unable to obtain NMPA approval for our products and drug candidates to be eligible for an expedited registration pathway as Category 1 drug candidates, the time and cost we incur to obtain regulatory approvals may increase. Even if we receive such Category 1 designation, it may not lead to a faster development, review or approval process.

The NMPA categorizes domestically-manufactured innovative drug applications as Category 1, provided such drug has a new and clearly defined structure, pharmacological property and apparent clinical value and has not been marketed anywhere in the world. Domestically developed and manufactured innovative drugs will be attributed to Category 1 for their clinical trial application, or CTA, and NDA applications. While some multinational pharmaceutical companies may file CTAs with the NMPA prior to approval of a drug in another country in order to take advantage of Category 1 classification, such drug will most likely be assigned to Category 5, a class designated for drugs that were approved outside China before the NMPA approval for NDA approval purposes. This is because, based on historical observations, multinational pharmaceutical companies would typically not prioritize China as the first market for product launch, hence subjecting the drug to the Category 5 status. Because margetuximab and durlobactam (ETX2514) are imported drug products, they will be subject to Category 5 status if they are approved by the NMPA. Our CTAs for ZEJULA and omadacycline (ZL-2401) were approved as Category 1 drugs by the NMPA. A Category 1 designation by the NMPA may not be granted for any of our other drug candidates that will not be first approved in China or, if granted, such designation may not lead to faster development or regulatory review or approval process. Moreover, a Category 1 designation does not increase the likelihood that our product or drug candidates will receive regulatory approval. Optune is a medical device and does not follow the NMPA drug categorization.

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Furthermore, despite positive regulatory changes introduced since 2015 which significantly accelerated time to market for innovative drugs, the regulatory process in China is still relatively ambiguous and unpredictable. The NMPA might require us to change our planned clinical study design or otherwise spend additional resources and effort to obtain approval of our drug candidates. In addition, policy changes may contain significant limitations related to use restrictions for certain age groups, warnings, precautions or contraindications, or may be subject to burdensome post-approval study or risk management requirements. If we are unable to obtain regulatory approval for our drug candidates in one or more jurisdictions, or any approval contains significant limitations, we may not be able to obtain sufficient funding or generate sufficient revenue to continue the development of our drug candidates or any other drug candidate that we may in-license, acquire or develop in the future.

Even if we receive regulatory approval for our products or any drug candidates, we will be subject to ongoing obligations and continued regulatory review, which may result in significant additional expense, and if we fail to comply with ongoing regulatory requirements or experience any unanticipated problems with any of our products or drug candidates, we may be subject to penalties.

Even after obtaining regulatory approval, our products and drug candidates will be subject to, among other things, ongoing regulatory requirements governing the labeling, packaging, promotion, recordkeeping, data management and submission of safety, efficacy and other post-market information. These requirements include submissions of safety and other post-marketing information and reports, registration, and continued compliance with cGMPs and GCPs. For example, ZEJULA and Optune will continue to be subject to post-approval development and regulatory requirements, which may limit how they are manufactured and marketed, and could materially impair our ability to generate revenue. As such, we and our partners and any of our and their respective contract manufacturers will be subject to ongoing review and periodic inspections to assess compliance with applicable post-approval regulations. Additionally, to the extent we want to make certain changes to the approved products, product labeling, or manufacturing processes, we will need to submit new applications or supplements to the Hong Kong Department of Health and the NMPA and obtain the agencies’ approval.

Additionally, any additional regulatory approvals that we receive for our products or drug candidates may also be subject to limitations on the approved indicated uses for which the products or drug may be marketed or to the conditions of approval, or contain requirements for potentially costly post-marketing testing, including Phase IV studies for the surveillance and monitoring the safety and efficacy of the products or drug.

In addition, once a product or drug is approved by the NMPA, FDA or a comparable regulatory authority for marketing, it is possible that there could be a subsequent discovery of previously unknown problems with the product or drug, including problems with third-party manufacturers or manufacturing processes, or failure to comply with regulatory requirements. If any of the foregoing occurs with respect to our products or drug products, it may result in, among other things:

Any government investigation of alleged violations of law could require us to expend significant time and resources and could generate negative publicity. Moreover, regulatory policies may change or additional government regulations may be enacted that could prevent, limit or delay regulatory approval of our products or drug candidates. If we are not able to maintain regulatory compliance, regulatory approval that has been obtained may be lost and we may not achieve or sustain profitability, which may harm our business, financial condition and prospects significantly.

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The incidence and prevalence for target patient populations of our products and drug candidates are based on estimates and third-party sources. If the market opportunities for our products and drug candidates are smaller than we estimate or if any approval that we obtain is based on a narrower definition of the patient population, our revenue and ability to achieve profitability might be materially and adversely affected.

Periodically, we make estimates regarding the incidence and prevalence of target patient populations for particular diseases based on various third-party sources and internally generated analysis and use such estimates in making decisions regarding our product and drug development strategy, including acquiring or in-licensing products or drug candidates and determining indications on which to focus in pre-clinical or clinical trials.

These estimates may be inaccurate or based on imprecise data. For example, the total addressable market opportunity will depend on, among other things, their acceptance by the medical community and patient access, product and drug pricing and reimbursement. The number of patients in the addressable markets may turn out to be lower than expected, patients may not be otherwise amenable to treatment with our products or drugs, or new patients may become increasingly difficult to identify or gain access to, all of which may significantly harm our business, financial condition, results of operations and prospects.

The recent restructure of the drug regulatory authorities may delay approval of our products or drug candidates.

On March 17, 2018, China’s highest legislative body, the National People’s Congress, approved a sweeping government restructuring plan. This is generally considered to be the most comprehensive government restructuring that China has undertaken since its “Open Door” policy in the late 1970s. As part of the new plan, China has established a State Market Regulatory Administration, or SMRA, which merges and undertakes the responsibilities previously held by the China State Food and Drug Administration, or SFDA, the State Administration for Industry and Commerce, or SAIC, General Administration of Quality Supervision, Inspection and Quarantine, or AQSIQ, price supervision and antitrust enforcement responsibilities previously held by the National Development and Reform Commission, or NDRC, the antitrust enforcement responsibilities previously held by the Ministry of Commerce, or MOFCOM, and the Antimonopoly and Anti-Unfair Competition Bureau of State Council, as well as the responsibilities previously held by the Certification and Accreditation Administration, or CAC, and the Standardization Administration of China, or SAC.

The new NMPA reports to the SMRA, is responsible for the review and approval of drugs, medical devices and cosmetics, and maintains its own branches at the provincial level and leave the post-approval enforcement authorities at the local level to the consolidated SMRA branches.

Although the NMPA is fully functional as of 2019 and the restructuring at the state, municipal and county level authorities has been mostly completed as of July 2019, there could still be delays in the NMPA’s implementation of the new reform initiatives and disruption in the NMPA’s routine operations due to personnel reshuffling post-restructuring.

Our future success depends on our ability to retain key executives and to attract, retain and motivate qualified personnel.

We are highly dependent on the expertise of the members of our research and development team, as well as the other principal members of our management, including Samantha Du, our founder, Chairman and Chief Executive Officer. Although we have entered into employment letter agreements with our executive officers, each of them may terminate their employment with us at any time with one months’ prior written notice. We do not maintain “key person” insurance for any of our executives or other employees.

Recruiting and retaining qualified management, scientific, clinical, manufacturing and sales and marketing personnel will also be critical to our success. The loss of the services of certain of our executive officers or other key employees could impede the achievement of our research, development and commercialization objectives and seriously harm our ability to successfully implement our business strategy. Furthermore, replacing certain of our executive officers and key employees may be difficult and may take an extended period of time because of the limited number of individuals in our industry with the breadth of skills and experience required to successfully develop, gain regulatory approval of and commercialize drugs. Competition to hire from this limited pool is intense, and we may be unable to hire, train, retain or motivate these key personnel on acceptable terms given the competition among numerous pharmaceutical and biotechnology companies for similar personnel. We also experience competition for the hiring of scientific and clinical personnel from universities and research institutions. In addition, our management will be required to devote significant time to new compliance initiatives from our status as a U.S. public company, which may require us to recruit more management personnel. Failure to succeed in clinical trials may make it more challenging to recruit and retain qualified scientific personnel.

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We will need to increase the size and capabilities of our organization, and we may experience difficulties in managing our growth.

We expect to experience significant growth in the number of our employees and consultants and the scope of our operations, particularly in the areas of drug development, drug commercialization, regulatory affairs and business development. To manage our anticipated future growth, we must continue to implement and improve our managerial, operational and financial systems, expand our facilities and continue to recruit and train additional qualified personnel. Due to our limited financial resources and the limited experience of our management team in managing a company with such anticipated growth, we may not be able to effectively manage the expansion of our operations or recruit and train additional qualified personnel. The expansion of our operations may lead to significant costs and may divert our management and business development resources. Any inability to manage growth could delay the execution of our business plans or disrupt our operations, and have a materially adverse effect on our business.

In addition to in-licensing or acquiring drug candidates, we may engage in future business acquisitions that could disrupt our business, cause dilution to our ADS holders and harm our financial condition and operating results.

We have, from time to time, evaluated partnership opportunities or investments and may, in the future, make acquisitions of, or investments in, companies that we believe have products or capabilities that are a strategic or commercial fit with our current drug candidates and business or otherwise offer opportunities for our company. In connection with these acquisitions or investments, we may:

We also may be unable to find suitable acquisition candidates and we may not be able to complete partnership opportunities or investments on favorable terms, if at all. If we do enter into partnership opportunities or investments, we cannot assure you that it will ultimately strengthen our competitive position or that it will not be viewed negatively by customers, financial markets or investors. Further, future partnership opportunities or investments could also pose numerous additional risks to our operations, including:

We may not be able to complete one or more partnership opportunities or investments or effectively integrate the operations, products or personnel gained through any such partnership opportunities or investments without a material adverse effect on our business, financial condition and results of operations.

We may need to significantly concede on prices for ZEJULA, Optune or our other drug candidates and devices for which we may receive regulatory approval in China and face uncertainty of reimbursement, which could diminish our sales or affect our profitability.

The regulations that govern pricing and reimbursement for pharmaceutical drugs and devices vary widely from country to country. In China, the newly created National Healthcare Security Administration, or NHSA, an agency responsible for administering China’s social security system, organized a price negotiation with drug companies for 119 new drugs that had not been included in the National Reimbursable Drug List, or the NRDL, at the time of the

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negotiation in November 2019, which resulted in an average price reduction by over 60% for 70 of the 119 drugs that passed the negotiation. NHSA, together with other government authorities, review the inclusion or removal of drugs from China’s National Drug Catalog for Basic Medical Insurance, Work-related Injury Insurance and Maternity Insurance, or the NRDL, or provincial or local medical insurance catalogues for the national medical insurance program regularly, and the tier under which a drug or device will be classified, both of which affect the amounts reimbursable to program participants for their purchases of those drugs. These determinations are made based on a number of factors, including price and efficacy. In November 2019, the NRDL was expanded to include 70 new drugs.

We may also be invited to attend the price negotiation with NHSA upon receiving regulatory approval in China, but we will likely need to significantly reduce our prices, and to negotiate with each of the provincial healthcare security administrations on reimbursement ratios. If we were to successfully launch commercial sales of our oncology-based product and drug candidates, including ZEJULA and Optune, our revenue from such sales is largely expected to be self-paid by patients, which may make our drug candidates and devices less desirable. On the other hand, if the NHSA or any of its local counterpart includes our drugs and devices in the NRDL or provincial RDL, which may increase the demand for our drug candidates and devices, our potential revenue from the sales of our drug candidates and devices may still decrease as a result of lower prices.

Moreover, eligibility for reimbursement in China does not imply that any drug or device will be paid for in all cases or at a rate that covers our costs, including licensing fees, research, development, manufacture, sale and distribution.

Companies in China that manufacture or sell drugs and medical devices are required to comply with extensive regulations and hold a number of permits and licenses to carry on their business. Our ability to obtain and maintain these regulatory approvals is uncertain, and future government regulation may place additional burdens on our efforts to commercialize our drug candidates.

The life sciences industry in China is subject to extensive government regulation and supervision. The regulatory framework addresses all aspects of operating in the pharmaceutical industry, including approval, registration, production, distribution, packaging, labelling, storage and shipment, advertising, licensing and certification requirements and procedures, periodic renewal and reassessment processes, registration of new products and environmental protection. Violation of applicable laws and regulations may materially and adversely affect our business. In order to manufacture and distribute drug and medical device products in China, we are required to:

If we are unable to obtain or renew such permits or any other permits or licenses required for our operations, will not be able to engage in the commercialization, manufacture and distribution of our products and drug candidates and our business may be adversely affected.

The regulatory framework governing the pharmaceutical industry in China is subject to change and amendment from time to time. Any such change or amendment could materially and adversely impact our business, financial condition and prospects. China government has introduced various reforms to the Chinese healthcare system in recent years and may continue to do so, with an overall objective to expand basic medical insurance coverage and improve the quality and reliability of healthcare services without incurring significant fiscal burden. The specific regulatory changes under the reform still remain uncertain. The implementing measures to be issued may not be sufficiently effective to achieve the stated goals, and as a result, we may not be able to benefit from such reform to the level we expect, if at all. Moreover, the reform could give rise to regulatory developments, such as more burdensome administrative procedures, which may have an adverse effect on our business and prospects.

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For further information regarding government regulation in China and other jurisdictions, see “Regulation—Government Regulation of Pharmaceutical Product Development and Approval,” “Regulation—Coverage and Reimbursement” and “Regulation—Other Healthcare Laws.”

If we breach our license or other intellectual property-related agreements for our products or drug candidates or otherwise experience disruptions to our business relationships with our licensors and collaboration partners, we could lose the ability to continue the development and commercialization of our products and drug candidates.

Our business relies, in large part, on our ability to develop and commercialize products and drug candidates from third parties including ZEJULA from GSK; Optune from Novocure Limited, or Novocure; omadacycline (ZL-2401) from Paratek Pharmaceuticals, or Paratek; bemarituzumab (FPA144) from Five Prime Therapeutics, Inc., or Five Prime; durlobactam from Entasis Therapeutics Holdings, Inc., or Entasis; margetuximab, MGD-013 and a pre-clinical multi-specific TRIDENT molecule from MacroGenics Inc., or MacroGenics; ripretinib from Deciphera Pharmaceuticals, LLC, or Deciphera; INCMGA0012 (PD-1) from Incyte Corporation, or Incyte; and REGN1979 from Regeneron Pharmaceuticals, Inc., or Regeneron. If we have not obtained a license to all intellectual property rights that are relevant to our products and drug candidates and that are owned or controlled by our licensors and collaboration partners or owned or controlled by affiliates of such licensors and collaboration partners, we may need to obtain additional licenses to such intellectual property rights which may not be available on an exclusive basis, on commercially reasonable terms or at all. In addition, if our licensors and collaboration partners breach such agreements, we may not be able to enforce such agreements against our licensors’ parent entity or affiliates. Under each of our license and intellectual property-related agreements, in exchange for licensing or sublicensing us the right to develop and commercialize the applicable drug candidates, our licensors will be eligible to receive from us milestone payments, tiered royalties from commercial sales of such drug candidates, assuming relevant approvals from government authorities are obtained, or other payments. Our license and other intellectual property-related agreements also require us to comply with other obligations including development and diligence obligations, providing certain information regarding our activities with respect to such drug candidates and/or maintaining the confidentiality of information we receive from our licensors. For example, we are also obligated to use commercially reasonable efforts to develop and commercialize Optune, margetuximab, MGD-013, a pre-clinical multi-specific TRIDENT molecule, omadacycline (ZL-2401), bemarituzumab (FPA144), durlobactam, ripretinib, INCMGA0012 (PD-1) and REGN1979 in certain of their respective territories, in each case, under their respective agreements.

If we fail to meet any of our obligations under our license and other intellectual property-related agreements, our licensors have the right to terminate our licenses and sublicenses and, upon the effective date of such termination, have the right to re-obtain the licensed and sub-licensed technology and intellectual property. If any of our licensors terminate any of our licenses or sublicenses, we will lose the right to develop and commercialize our applicable products and drug candidates and other third parties may be able to market products or drug candidates similar or identical to ours. In such case, we may be required to provide a grant back license or expand an existing license to the licensors under our own intellectual property with respect to the terminated products. In addition, if our agreements with GSK for ZEJULA terminate for any reason, we are required to grant GSK an exclusive license to certain of our intellectual property rights that relate to ZEJULA, as applicable. Furthermore, if our agreement with MacroGenics for margetuximab, MGD-013 and a pre-clinical multi-specific TRIDENT molecule is terminated by MacroGenics for certain reasons, we are required to grant MacroGenics an option to convert the non-exclusive license granted to MacroGenics to use certain of our intellectual property rights that relate to margetuximab, MGD-013 and a pre-clinical multi-specific TRIDENT molecule in China, Hong Kong, Macau and Taiwan to an exclusive license. If our agreement with Entasis for durlobactam is terminated for certain reasons, we are required to grant Entasis an exclusive, fully paid, royalty free, perpetual irrevocable and sublicenseable (through multiple tiers) license to use certain of our intellectual property rights that relate to EXT2514 in the licensed territory. If our agreement with Incyte for INCMGA0012 (PD-1) is terminated for certain reasons, we are required to assign to Incyte certain trademarks and certain other business premises, data and regulatory materials that relate to INCMGA0012 (PD-1). If our agreement with Deciphera for ripretinib is terminated for certain reasons, we are required to grant Deciphera a worldwide, perpetual and irrevocable license to use certain of our intellectual property rights that relate to ripretinib in China, Hong Kong, Macau and Taiwan. While we would expect to exercise all rights and remedies available to us, including seeking to cure any breach by us, and otherwise seek to preserve our rights under the intellectual property rights licensed and sublicensed to us, we may not be able to do so in a timely manner, at an acceptable cost or at all. In particular, some of the milestone payments are payable upon our drug candidates reaching development milestones before we have commercialized, or received any revenue from, sales of such drug candidate, and we cannot guarantee that we will have sufficient resources to make such milestone payments. Any uncured, material breach under the agreements could result in our loss of exclusive rights and may lead to a complete termination of our rights to the applicable drug candidate. Any of the foregoing could have a material adverse effect on our business, financial conditions, results of operations, and prospects.

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In addition, disputes may further arise regarding intellectual property subject to a license and/or collaboration agreement, including, but not limited to:

Moreover, certain of our licensors do not own some or all of the intellectual property included in the license, but instead have licensed such intellectual property from a third party, and have granted us a sub-license. As a result, the actions of our licensors or of the ultimate owners of the intellectual property may affect our rights to use our sublicensed intellectual property, even if we are in compliance with all of the obligations under our license agreements. For example, our licenses from GSK, Paratek, MacroGenics and Incyte comprise sublicenses to us of certain intellectual property rights owned by third parties that are not our direct licensors. If our licensors were to fail to comply with their obligations under the agreements pursuant to which they obtain the rights that are sublicensed to us, or should such agreements be terminated or amended, our rights to the applicable licensed intellectual property may be terminated or narrowed, our exclusive licenses may be converted to non-exclusive licenses, and our ability to produce and sell our products and drug candidates may be materially harmed. In addition, our license from Paratek is limited to intellectual property rights under the control of Paratek Bermuda, Ltd. To the extent Paratek Bermuda, Ltd. loses control over any of the licensed intellectual property rights for any reason, we will no longer be licensed to such intellectual property rights to use, develop and otherwise commercialize omadacycline (ZL-2401). Any of the foregoing could have a material adverse effect on our business, financial conditions, results of operations, and prospects.

In addition, the agreements under which we currently license or have rights to use intellectual property or technology from third parties are complex, and certain provisions in such agreements may be susceptible to multiple interpretations. The resolution of any contract interpretation disagreement that may arise could narrow what we believe to be the scope of our rights to the relevant intellectual property or technology, or increase what we believe to be our financial or other obligations under the relevant agreement, either of which could have a material adverse effect on our business, financial condition, results of operations, and prospects. Moreover, if disputes over intellectual property that we have licensed, sublicensed or obtained rights to use prevent or impair our ability to maintain our current licensing arrangements on commercially acceptable terms, we may be unable to successfully develop and commercialize the affected products or drug candidates, which could have a material adverse effect on our business, financial conditions, results of operations and prospects.

Product liability claims or lawsuits could cause us to incur substantial liabilities.

We face an inherent risk of product liability exposure related to the use of our products and drug candidates in clinical trials or any products or drug candidates we may decide to commercialize and manufacture. If we cannot successfully defend against claims that the use of such products or drug candidates in our clinical trials or any products that we procure from third-party manufacturers, or that we may choose to manufacture at our production facilities in the future, including any of our products or drug candidates which receive regulatory approval, caused injuries, we could incur substantial liabilities. Regardless of merit or eventual outcome, liability claims may result in:

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Any litigation might result in substantial costs and diversion of resources. While we maintain liability insurance for certain clinical trials (which covers the patient human clinical trial liabilities including, among others, bodily injury), product liability insurance to cover our product liability claims and general liability insurance to cover other commercial liability claims, these insurances may not fully cover our potential liabilities. Additionally, inability to obtain sufficient insurance coverage at an acceptable cost could prevent or inhibit the successful commercialization of products or drugs we develop, alone or with our collaborators.

The research and development projects under our internal discovery programs are at an early stage of development. As a result, we are unable to predict if or when we will successfully develop or commercialize any drug candidates under such programs.

Our internal discovery programs are at an early stage of development and will require significant investment and regulatory approvals prior to commercialization. Each of our drug candidates will require additional clinical and pre-clinical development, management of clinical, pre-clinical and manufacturing activities, obtaining regulatory approval, obtaining manufacturing supply, building of a commercial organization, substantial investment and significant marketing efforts before they generate any revenue from product sales. We are not permitted to market or promote any of our drug candidates before we receive regulatory approval from the NMPA, the FDA or comparable regulatory authorities, and we may never receive such regulatory approval for any such drug candidates.

We cannot be certain that clinical development of any drug candidates from our internal discovery programs will be successful or that we will obtain regulatory approval or be able to successfully commercialize any of our drug candidates and generate revenue. Success in pre-clinical testing does not ensure that clinical trials will be successful, and the clinical trial process may fail to demonstrate that our drug candidates are safe and effective for their proposed uses. Any such failure could cause us to abandon further development of any one or more of our drug candidates and may delay development of other drug candidates. Any delay in, or termination of, our clinical trials will delay and possibly preclude the filing of any NDAs with the NMPA, the FDA or comparable regulatory authorities and, ultimately, our ability to commercialize our drug candidates and generate product revenue.

If our manufacturing facilities are not approved by regulators, are damaged or destroyed or production at such facilities is otherwise interrupted, our business and prospects would be negatively affected.

In 2017, we built a small molecule facility capable of supporting clinical and commercial production, and in 2018, we built a large molecule facility in Suzhou, China using GE Healthcare FlexFactory platform technology capable of supporting clinical production of our drug candidates. We intend to rely on these facilities for the manufacture of clinical and commercial supply of some of our products or drug candidates. Prior to being permitted to sell any products or drugs produced at these facilities, the facilities will need to be inspected and approved by regulatory authorities. If either facility is not approved by regulators or is damaged or destroyed, or otherwise subject to disruption, it would require substantial lead-time to replace our manufacturing capabilities. In such event, we would be forced to identify and rely partially or entirely on third-party contract manufacturers for an indefinite period of time. Any new facility needed to replace an existing production facility would need to comply with the necessary regulatory requirements and be tailored to our production requirements and processes. We also would need regulatory approvals before using any products or drugs manufactured at a new facility in clinical trials or selling any products or drugs that are ultimately approved. Any disruptions or delays at our facility or its failure to meet regulatory compliance would impair our ability to develop and commercialize our products or drug candidates, which would adversely affect our business and results of operations.

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We may become involved in lawsuits to protect or enforce our intellectual property.

Competitors may infringe our patent rights or misappropriate or otherwise violate our intellectual property rights. To counter infringement or unauthorized use, litigation may be necessary in the future to enforce or defend our intellectual property rights, to protect our trade secrets or to determine the validity and scope of our own intellectual property rights or the proprietary rights of others. This can be expensive and time consuming. Any claims that we assert against perceived infringers could also provoke these parties to assert counterclaims against us alleging that we infringe their intellectual property rights. We may not be able to prevent third parties from infringing upon or misappropriating our intellectual property, particularly in countries where the laws may not protect intellectual property rights as fully as in the United States. An adverse result in any litigation proceeding could put our patent, as well as any patents that may issue in the future from our pending patent applications, at risk of being invalidated, held unenforceable or interpreted narrowly. Furthermore, because of the substantial amount of discovery required in connection with intellectual property litigation, there is a risk that some of our confidential information could be compromised by disclosure during this type of litigation.

If we are unable to protect the confidentiality of our trade secrets, our business and competitive position would be harmed. We may be subject to claims that our employees have wrongfully used or disclosed alleged trade secrets of their former employers.

In addition to our issued patent and pending patent applications, we rely on trade secrets, including unpatented know-how, technology and other proprietary information, to maintain our competitive position and to protect our drug candidates. We seek to protect these trade secrets, in part, by entering into nondisclosure and confidentiality agreements with parties that have access to them, such as our employees, corporate collaborators, outside scientific collaborators, sponsored researchers, contract manufacturers, consultants, advisors and other third parties. We also enter into confidentiality and invention or patent assignment agreements with our employees and consultants. However, any of these parties may breach such agreements and disclose our proprietary information, and we may not be able to obtain adequate remedies for such breaches. Enforcing a claim that a party illegally disclosed or misappropriated a trade secret can be difficult, expensive and time-consuming, and the outcome is unpredictable. If any of our trade secrets were to be lawfully obtained or independently developed by a competitor, we would have no right to prevent them from using that technology or information to compete with us and our competitive position would be harmed.

Furthermore, many of our employees, including our senior management, were previously employed at other biotechnology or pharmaceutical companies, including our competitors or potential competitors. Some of these employees, including each member of our senior management, executed proprietary rights, nondisclosure and non-competition agreements in connection with such previous employment. Although we try to ensure that our employees do not use the proprietary information or know-how of others in their work for us, we may be subject to claims that we or these employees have used or disclosed intellectual property, including trade secrets or other proprietary information, of any such employee’s former employer. We are not aware of any threatened or pending claims related to these matters or concerning the agreements with our senior management, but in the future litigation may be necessary to defend against such claims. If we fail in defending any such claims, in addition to paying monetary damages, we may lose valuable intellectual property rights or personnel. Even if we are successful in defending against such claims, litigation could result in substantial costs and be a distraction to management.

Our internal computer systems, or those used by our CROs or other contractors or consultants, may fail or suffer security breaches.

Despite the implementation of security measures, our internal computer systems and those of our CROs and other contractors and consultants are vulnerable to damage from computer viruses and unauthorized access. Although to our knowledge we have not experienced any material system failure or security breach to date, if such an event were to occur and cause interruptions in our operations, it could result in a material disruption of our development programs and our business operations.

The data privacy regime in China and in the United States are evolving and there may be more stringent compliance requirements for the collection, processing, use, and transfer of personal information and important data. In the ordinary course of our business, we collect and store sensitive data, including, among other things, legally protected patient health information, personally identifiable information about our employees, intellectual property, and proprietary business information. We manage and maintain our applications and data utilizing on-site systems and outsourced vendors. These applications and data encompass a wide variety of business critical information including

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research and development information, commercial information and business and financial information. Because information systems, networks and other technologies are critical to many of our operating activities, shutdowns or service disruptions at our company or vendors that provide information systems, networks, or other services to us pose increasing risks. Such disruptions may be caused by events such as computer hacking, phishing attacks, ransomware, dissemination of computer viruses, worms and other destructive or disruptive software, denial of service attacks and other malicious activity, as well as power outages, natural disasters (including extreme weather), terrorist attacks or other similar events. Such events could have an adverse impact on us and our business, including loss of data and damage to equipment and data. In addition, system redundancy may be ineffective or inadequate, and our disaster recovery planning may not be sufficient to cover all eventualities. Significant events could result in a disruption of our operations, damage to our reputation or a loss of revenues, and invite regulator’s scrutiny. In addition, we may not have adequate insurance coverage to compensate for any losses associated with such events.

We could be subject to risks caused by misappropriation, misuse, leakage, falsification or intentional or accidental release or loss of information maintained in the information systems and networks of our company and our vendors, including personal information of our employees and patients, and company and vendor confidential data. In addition, outside parties may attempt to penetrate our systems or those of our vendors or fraudulently induce our personnel or the personnel of our vendors to disclose sensitive information in order to gain access to our data and/or systems. Like other companies, we may experience threats to our data and systems, including malicious codes and viruses, phishing, and other cyber-attacks. The number and complexity of these threats continue to increase over time. If a material breach of our information technology systems or those of our vendors occurs, the market perception of the effectiveness of our security measures could be harmed and our reputation and credibility could be damaged. We could be required to expend significant amounts of money and other resources to repair or replace information systems or networks. Although we develop and maintain systems and controls designed to prevent these events from occurring, and we have a process to identify and mitigate threats, the development and maintenance of these systems, controls and processes is costly and requires ongoing monitoring and updating as technologies change and efforts to overcome security measures become increasingly sophisticated. Moreover, despite our efforts, the possibility of these events occurring cannot be eliminated entirely. As we outsource more of our information systems to vendors, engage in more electronic transactions with payors and patients, and rely more on cloud-based information systems, the related security risks will increase and we will need to expend additional resources to protect our technology and information systems.

We are subject to laws and government regulations relating to privacy and data protection that have required us to modify certain of our policies and procedures with respect to the collection and processing of personal data, and future laws and regulations may cause us to incur additional expenses or otherwise limit our ability to collect and process personal data.

We may be subject to privacy and security laws in the various jurisdictions in which we operate, obtain or store personally identifiable information. The legislative and regulatory landscape for privacy and data protection continues to evolve, and there has been an increasing focus on privacy and data protection issues with the potential to affect our business.

Within the United States, our operations may be affected by the Health Insurance Portability and Accountability Act of 1996 as amended by the Health Information Technology for Economic and Clinical Health Act and its implementing regulations, collectively, HIPAA, which impose obligations on certain “covered entities” (healthcare providers, health plans and healthcare clearinghouses) and certain of their “business associate” contractors with respect to safeguarding the privacy, security and transmission of individually identifiable health information. Although we believe that we currently are neither a “covered entity” nor a “business associate” under the legislation, a business associate relationship may be imputed from facts and circumstances even in the absence of an actual business associate agreement. In addition, HIPAA may affect our interactions with customers who are covered entities or their business associates because HIPAA affects the ability of these entities to disclose patient health information to us. The federal government, various states and localities also have laws that regulate the privacy and security of personal information and so may affect our business operations. For example, we are subject to the California Consumer Privacy Act, or CCPA, that became effective on January 1, 2020. The CCPA gives California consumers (defined to include all California residents) certain rights, including the right to ask companies to disclose details about the personal information they collect, as well as other rights such as the right to ask companies to delete a consumer’s personal information and opt out of the sale of personal information.

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We could be subject to regulatory actions and/or claims made by individuals and groups in private litigation involving privacy issues related to data collection and use practices and other data privacy laws and regulations, including claims under the laws described, as well as for alleged unfair or deceptive practices. If our operations are found to be in violation of any of the privacy laws, rules or regulations that apply to us, we could be subject to penalties, including civil penalties, damages, injunctive relief, and other penalties, which could adversely affect our ability to operate our business and our financial results. We will continue to review these and all future privacy and other laws and regulations to assess whether additional procedural safeguards are warranted, which may cause us to incur additional expenses or otherwise limit our ability to collect and process personal data.

Risks Related to Our Dependence on Third Parties

We rely on third parties to conduct our pre-clinical and clinical trials. If these third parties do not successfully carry out their contractual duties or meet expected deadlines, we may not be able to obtain regulatory approval for or commercialize our products or drug candidates and our business could be substantially harmed.

We have relied upon and plan to continue to rely upon third-party CROs to monitor and manage data for some of our ongoing pre-clinical and clinical programs. We rely on these parties for execution of our pre-clinical and clinical trials, and control only certain aspects of their activities. Nevertheless, we are responsible for ensuring that each of our studies is conducted in accordance with the applicable protocol and legal, regulatory and scientific standards, and our reliance on the CROs does not relieve us of our regulatory responsibilities. We also rely on third parties to assist in conducting our pre-clinical studies in accordance with Good Laboratory Practices, or GLP, and the Administrative Regulations on Experimental Animals or the Animal Welfare Act requirements. We and our CROs are required to comply with GCP regulations and guidelines enforced by the NMPA, and comparable foreign regulatory authorities for all of our products or drug candidates in clinical development. Regulatory authorities enforce these GCP requirements through periodic inspections of trial sponsors, investigators and trial sites. If we or any of our CROs fail to comply with applicable GCP requirements, the clinical data generated in our clinical trials may be deemed unreliable and the NMPA or comparable foreign regulatory authorities may require us to perform additional clinical trials before approving our marketing applications. We cannot assure that upon inspection by a given regulatory authority, such regulatory authority will determine that any of our clinical trials comply with GCP requirements. In addition, our clinical trials must be conducted with products or drugs produced under cGMP requirements. Failure to comply with these regulations may require us to repeat pre-clinical and clinical trials, which would delay the regulatory approval process.

Our CROs are not our employees, and except for remedies available to us under our agreements with such CROs, we cannot control whether or not they devote sufficient time and resources to our on-going clinical, nonclinical and pre-clinical programs. If CROs do not successfully carry out their contractual duties or obligations or meet expected deadlines or if the quality or accuracy of the clinical data they obtain is compromised due to their failure to adhere to our clinical protocols, regulatory requirements or for other reasons, our clinical trials may be extended, delayed or terminated and we may not be able to obtain regulatory approval for or successfully commercialize our products or drug candidates. As a result, our results of operations and the commercial prospects for our products and drug candidates would be harmed, our costs could increase and our ability to generate revenues could be delayed or compromised.

Because we rely on third parties, our internal capacity to perform these functions is limited. Outsourcing these functions involves risk that third parties may not perform to our standards, may not produce results in a timely manner or may fail to perform at all. In addition, the use of third-party service providers requires us to disclose our proprietary information to these parties, which could increase the risk that this information will be misappropriated. We currently have a small number of employees, which limits the internal resources we have available to identify and monitor our third-party providers. To the extent we are unable to identify and successfully manage the performance of third-party service providers in the future, our business may be adversely affected. Though we carefully manage our relationships with our CROs, there can be no assurance that we will not encounter similar challenges or delays in the future or that these delays or challenges will not have a material adverse impact on our business, financial condition and prospects.

If we lose our relationships with CROs, our product or drug development efforts could be delayed.

We rely on third-party vendors and CROs for some of our pre-clinical studies and clinical trials related to our product or drug development efforts. Switching or adding additional CROs involves additional cost and requires management time and focus. Our CROs have the right to terminate their agreements with us in the event of an uncured material breach. In addition, some of our CROs have an ability to terminate their respective agreements with us if it can be reasonably demonstrated that the safety of the subjects participating in our clinical trials warrants such termination, if we make a general assignment for the benefit of our creditors or if we are liquidated. Identifying, qualifying and

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managing performance of third-party service providers can be difficult, time-consuming and cause delays in our development programs. In addition, there is a natural transition period when a new CRO commences work and the new CRO may not provide the same type or level of services as the original provider. If any of our relationships with our third-party CROs are terminated, we may not be able to enter into arrangements with alternative CROs or to do so on commercially reasonable terms, and we may not be able to meet our desired clinical development timelines.

We have limited experience manufacturing our products and drug candidates on a large clinical or commercial scale. We are or will be dependent on third party manufacturers for the manufacture of certain of our products and drug candidates as well as on third parties for our supply chain, and if we experience problems with any of these third parties, the manufacture of our products or drug candidates or products could be delayed, which could harm our results of operations.

If our two manufacturing facilities are unable to meet our intended production capacity in a timely fashion, we may have to engage a contract manufacturing organization, or CMO, for the production of clinical supplies of our products or drug candidates.

Additionally, in order to successfully commercialize our products and drug candidates, we will need to identify qualified CMOs for the scaled production of a commercial supply of certain of our products and drug candidates. The CMOs should be drug manufacturers holding manufacturing permits with a scope that can cover our drug registration candidates, and such CMO arrangement should be approved by the NMPA’s provincial level branches. We have not yet identified suppliers to support scaled production. If we are unable to arrange for alternative third-party manufacturing sources, or to do so on commercially reasonable terms or in a timely manner, or to obtain the NMPA approval for our CMO arrangement in a timely manner, we may not be able to complete development of our products or drug candidates, or market or distribute them.

We rely on third-party manufacturers to manufacture at least some of our products and drug candidates. For example, we rely on MacroGenics to manufacture and supply margetuximab, MGD-013, and a pre-clinical multi-specific TRIDENT molecule, Entasis to manufacture and supply durlobactam, Novocure to manufacture and supply Optune, Deciphera to manufacture and supply ripretinib, Incyte to manufacture and supply INCMGA0012 (PD-1) and, as of April 2020, Regeneron to manufacture and supply REGN1979.

Such reliance entails risks to which we would not be subject to if we manufactured drug candidates or products ourselves, including reliance on the third party for regulatory compliance and quality assurance, the possibility of breach of the manufacturing or supply agreement by the third party because of factors beyond our control (including a failure to synthesize and manufacture our drug candidates or any products we may eventually commercialize in accordance with our specifications) and the possibility of termination or nonrenewal of the agreement by the third party, based on its own business priorities, at a time that is costly or damaging to us. In addition, the NMPA and other regulatory authorities require that our drug candidates and any products that we may eventually commercialize be manufactured according to cGMP standards. Any failure by our third-party manufacturers to comply with cGMP standards or failure to scale up manufacturing processes, including any failure to deliver sufficient quantities of drug candidates in a timely manner, could lead to a delay in, or failure to obtain, regulatory approval of any of our drug candidates. In addition, such failure could be the basis for the NMPA to issue a warning or untitled letter, withdraw approvals for drug candidates previously granted to us, or take other regulatory or legal action, including recall or seizure, total or partial suspension of production, suspension of ongoing clinical trials, refusal to approve pending applications or supplemental applications, detention or product, refusal to permit the import or export of products, injunction, or imposing civil and criminal penalties.

Any significant disruption in our potential supplier relationships could harm our business. We currently source key materials from third parties, either directly through agreements with suppliers or indirectly through our manufacturers who have agreements with suppliers, as well as through our licensors. We anticipate that, in the near term, all key materials will be sourced through third parties. There are a small number of suppliers for certain capital equipment and key materials that are used to manufacture some of our drugs. Such suppliers may not sell these key materials to us or our manufacturers at the times we need them or on commercially reasonable terms. We currently do not have any agreements for the commercial production of these key materials. Any significant delay in the supply of a product or drug candidate or its key materials for an ongoing clinical study could considerably delay completion of our clinical studies, product or drug testing and potential regulatory approval of our products or drug candidates. If we or our manufacturers are unable to purchase these key materials after regulatory approval has been obtained for our drug candidates, the commercialization of our products or the commercial launch of our drug candidates could be delayed or there could be a shortage in supply, which would impair our ability to generate revenues from the sale of our products and drug candidates.

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Furthermore, because of the complex nature of our compounds, we or our manufacturers may not be able to manufacture our compounds at a cost or in quantities or in a timely manner necessary to make commercially successful products and drugs. In addition, as our drug development pipeline increases and matures, we will have a greater need for clinical study and commercial manufacturing capacity. We have limited experience manufacturing pharmaceutical products or drugs on a commercial scale and some of our current suppliers will need to increase their scale of production to meet our projected needs for commercial manufacturing, the satisfaction of which on a timely basis may not be met.

We depend on our licensors or patent owners of our in-licensed patent rights to prosecute and maintain patents and patent applications that are material to our business. Any failure by our licensors or such patent owners to effectively protect these patent rights could adversely impact our business and operations.

We have licensed and sublicensed patent rights from third parties for some of our development programs, including ZEJULA from GSK, Optune from Novocure, omadacycline (ZL-2401) from Paratek, bemarituzumab (FPA144) from Five Prime, durlobactam from Entasis, and margetuximab, MGD-013 and a pre-clinical multi-specific TRIDENT molecule from MacroGenics, ripretinib from Deciphera and INCMGA0012 (PD-1) from Incyte. As a licensee and sublicensee of third parties, we rely on these third parties to file and prosecute patent applications and maintain patents and otherwise protect the licensed intellectual property under certain of our license agreements. In addition, we have not had and do not have primary control over these activities for certain of our patents or patent applications and other intellectual property rights that we jointly own with certain of our licensors and sub-licensors. We cannot be certain that the patents and patent applications for our products and drug candidates have been or will be prepared, filed, prosecuted or maintained by such third parties in compliance with applicable laws and regulations, in a manner consistent with the best interests of our business, or in a manner that will result in valid and enforceable patents or other intellectual property rights that cover our drug candidates. If our licensors or such third parties fail to prepare, prosecute, or maintain such patent applications and patents, or lose rights to those patent applications or patents, the rights we have licensed may be reduced or eliminated, and our right to develop and commercialize any of our drug candidates that are subject of such licensed rights could be adversely affected.

Pursuant to the terms of the license agreements with some of our licensors, the licensors may have the right to control enforcement of our licensed patents or defense of any claims asserting the invalidity or unenforceability of these patents. For example, under our agreement with Novocure for Optune, Novocure owns and has the right to control all patent application and patent prosecution activities related to Optune in China, Hong Kong, Macau and Taiwan. Similarly, under our agreement with Five Prime for bemarituzumab (FPA144), Five Prime has the first right to enforce the licensed patents in China, Hong Kong, Macau and Taiwan, subject to certain exceptions. In addition, with respect to the patent portfolio for omadacycline (ZL-2401), which we sub-license from Paratek, Paratek has the first right to enforce such patent portfolio in territories outside of China, Hong Kong, Macau and Taiwan. Under our agreements with each of Entasis and Incyte, each of Entasis and Incyte has the first right to enforce the respective licensed patents in the licensed territory, including China, subject to certain exceptions. Under our agreement with Deciphera for ripretinib, Deciphera has the first right to enforce the licensed patents in China, Hong Kong, Macau and Taiwan, subject to certain exceptions. With respect to the patent portfolio for ZEJULA, which we sub-license from GSK, we have the first right to enforce such patent portfolio within China, Hong Kong and Macau. However, GSK maintains the right to enforce such patent portfolio in all other territories or, if we fail to bring an action within 90 days within China, Hong Kong or Macau, GSK can control such enforcement actions in those areas as well. In the case where GSK controls such enforcement actions, although we have rights to consult with GSK on such actions within China, Hong Kong and Macau, rights granted by GSK under ZEJULA to another licensee, such as Janssen Biotech, Inc. to whom GSK has granted an exclusive right to develop ZEJULA for the treatment of prostate cancer, could potentially influence GSK’s interests in the exercise of its prosecution, maintenance and enforcement rights in a manner that may favor the interests of such other licensee as compared with us, which could have a material adverse effect on our business, financial conditions, results of operations and prospects.

Even if we are permitted to pursue the enforcement or defense of our licensed and sub-licensed patents, we will require the cooperation of our licensors and any applicable patent owners and such cooperation may not be provided to us. We cannot be certain that our licensors will allocate sufficient resources or prioritize their or our enforcement of such patents or defense of such claims to protect our interests in the licensed patents. Even if we are not a party to these legal actions, an adverse outcome could harm our business because it might prevent us from continuing to license intellectual property that we may need to operate our business. If we lose any of our licensed intellectual property, our right to develop and commercialize any of our drug candidates that are subject of such licensed rights could be adversely affected.

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Other Risks and Risks Related to Doing Business in China

If we fail to comply with environmental, health and safety laws and regulations of China, we could become subject to fines or penalties or incur costs that could have a material adverse effect on the success of our business.

We are subject to numerous environmental, health and safety laws and regulations, including those governing laboratory procedures and the handling, use, storage, treatment and disposal of hazardous materials and wastes. Our operations primarily occur in China and involve the use of hazardous materials, including chemical materials. Our operations also produce hazardous waste products. We are therefore subject to PRC laws and regulations concerning the discharge of waste water, gaseous waste and solid waste during our processes of research and development of drugs. We engage competent third party contractors for the transfer and disposal of these materials and wastes. We may not at all times comply fully with environmental regulations. Any violation of these regulations may result in substantial fines, criminal sanctions, revocations of operating permits, shutdown of our facilities and obligation to take corrective measures. We cannot completely eliminate the risk of contamination or injury from these materials and wastes. In the event of contamination or injury resulting from the use or discharge of hazardous materials, we could be held liable for any resulting damages, and any liability could exceed our resources. We also could incur significant costs associated with civil, administrative or criminal fines and penalties.

Although we maintain workers’ compensation insurance to cover costs and expenses incurred due to on-the-job injuries to our employees and third party liability insurance for injuries caused by unexpected seepage, pollution or contamination, such insurance may not provide adequate coverage against potential liabilities. Furthermore, China government may take steps towards the adoption of more stringent environmental regulations. Due to the possibility of unanticipated regulatory or other developments, the amount and timing of future environmental expenditures may vary substantially from those currently anticipated. If there is any unanticipated change in the environmental regulations, we may need to incur substantial capital expenditures to install, replace, upgrade or supplement our manufacturing facility and equipment or make operational changes to limit any adverse impact or potential adverse impact on the environment in order to comply with new environmental protection laws and regulations. If such costs become prohibitively expensive, we may be forced to cease certain aspects of our business operations.

China’s economic, political and social conditions, as well as governmental policies, could affect the business environment and financial markets in China, our ability to operate our business, our liquidity and our access to capital.

Substantially all of our operations are conducted in China. Accordingly, our business, results of operations, financial condition and prospects may be influenced to a significant degree by economic, political, legal and social conditions in China as well as China’s economic, political, legal and social conditions in relation to the rest of the world. China’s economy differs from the economies of developed countries in many respects, including with respect to the amount of government involvement, level of development, growth rate, control of foreign exchange and allocation of resources. While China’s economy has experienced significant growth over the past 40 years, growth has been uneven across different regions and among various economic sectors of China. China’s government has implemented various measures to encourage economic development and guide the allocation of resources. Some of these measures may benefit the overall economy in China, but may have a negative effect on us. For example, our financial condition and results of operations may be adversely affected by government control over capital investments or changes in tax regulations that are currently applicable to us. In addition, in the past, China’s government implemented certain measures, including interest rate increases, to control the pace of economic growth. These measures may cause decreased economic activity in China, which may adversely affect our business and results of operation. More generally, if the business environment in China deteriorates from the perspective of domestic or international investment, our business in China may also be adversely affected.

Uncertainties with respect to Chinese legal system and changes in laws, regulations and policies in China could materially and adversely affect us.

We conduct our business primarily through our subsidiaries in China. PRC laws and regulations govern our operations in China. Our subsidiaries are generally subject to laws and regulations applicable to foreign investments in China, which may not sufficiently cover all of the aspects of our economic activities in China. In addition, the implementation of laws and regulations may be in part based on government policies and internal rules that are subject to the interpretation and discretion of different government agencies (some of which are not published on a timely basis or at all) that may have a retroactive effect. As a result, we may not always be aware of any potential violation of these

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policies and rules. Such unpredictability regarding our contractual, property and procedural rights could adversely affect our business and impede our ability to continue our operations. Furthermore, since PRC administrative and court authorities have significant discretion in interpreting and implementing statutory and contractual terms, it may be more difficult to evaluate the outcome of administrative and court proceedings and the level of legal protection we enjoy than in more developed legal systems. These uncertainties could materially and adversely affect our business and results of operations.

In January 2015, the Ministry of Commerce of China, or the MOFCOM, published a discussion draft of the proposed Foreign Investment Law. The Foreign Investment Law passed the legislative review in March 2019, and came into effect on January 1, 2020. Foreign-invested entities will enjoy national treatment in industry sectors that are not prohibited or restricted from foreign investment. The Foreign Investment Law imposes information reporting requirements on foreign investors and the applicable foreign invested entities. Non-compliance with the reporting requirements will result in corrective orders and fines between RMB 100,000 to 500,000. The Foreign Investment Law reinforces the duties of government authorities to protect intellectual property rights and trade secrets of foreign-investment entities. Government authorities cannot compel technology transfer by administrative means, reveal or provide trade secrets of foreign-invested entities to third parties. Last but not least, the Foreign Investment Law calls for the establishment of a foreign investment security review mechanism, details of which will be further developed by the Chinese government.

In addition, any administrative and court proceedings in China may be protracted, resulting in substantial costs and diversion of resources and management attention.

We may be exposed to liabilities under the U.S. Foreign Corrupt Practices Act, or FCPA, and Chinese anti-corruption laws, and any determination that we have violated these laws could have a material adverse effect on our business or our reputation.

We are subject to the FCPA. The FCPA generally prohibits us from making improper payments to non-U.S. officials for the purpose of obtaining or retaining business. We are also subject to the anti-bribery laws of other jurisdictions, particularly China. As our business continues to expand, the applicability of the FCPA and other anti-bribery laws to our operations will continue to increase. Our procedures and controls to monitor anti-bribery compliance may fail to protect us from reckless or criminal acts committed by our employees or agents. If we, due to either our own deliberate or inadvertent acts or those of others, fail to comply with applicable anti-bribery laws, our reputation could be harmed and we could incur criminal or civil penalties, other sanctions and/or significant expenses, which could have a material adverse effect on our business, including our financial condition, results of operations, cash flows and prospects.

Restrictions on currency exchange may limit our ability to receive and use financing in foreign currencies effectively.

Our PRC subsidiaries’ ability to obtain foreign exchange is subject to significant foreign exchange controls and, in the case of transactions under the capital account, requires the approval of and/or registration with PRC government authorities, including the state administration of foreign exchange, or SAFE. In particular, if we finance our PRC subsidiaries by means of foreign debt from us or other foreign lenders, the amount is not allowed to, among other things, exceed the statutory limits and such loans must be registered with the local counterpart of the SAFE. If we finance our PRC subsidiaries by means of additional capital contributions, the amount of these capital contributions must first be approved or filed by the relevant government approval authority.

In the light of the various requirements imposed by PRC regulations on loans to, and direct investment in, PRC entities by offshore holding companies, we cannot assure you that we will be able to complete the necessary government registrations or obtain the necessary government approvals on timely basis, if at all, with respect to future loans or capital contributions by us to our PRC subsidiaries. If we fail to complete such registrations or obtain such approval, our ability to capitalize or otherwise fund our PRC operations may be negatively affected, which could materially and adversely affect our liquidity and our ability to fund and expand our business.

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PRC regulations relating to the establishment of offshore special purpose companies by PRC residents may subject our PRC resident beneficial owners or our wholly foreign-owned subsidiaries in China to liability or penalties, limit our ability to inject capital into these subsidiaries, limit these subsidiaries’ ability to increase their registered capital or distribute profits to us, or may otherwise adversely affect us.

In 2014, SAFE promulgated the Circular on Relevant Issues Concerning Foreign Exchange Control on Domestic Residents’ Offshore Investment and Financing and Roundtrip Investment through Special Purpose Vehicles, or SAFE Circular 37. SAFE Circular 37 requires PRC residents to register with local branches of SAFE or competent banks designated by SAFE in connection with their direct establishment or indirect control of an offshore entity, for the purpose of overseas investment and financing, with such PRC residents’ legally owned assets or equity interests in domestic enterprises or offshore assets or interests, referred to in SAFE Circular 37 as a “special purpose vehicle.” The term “control” under SAFE Circular 37 is broadly defined as the operation rights, beneficiary rights or decision-making rights acquired by the PRC residents in the offshore special purpose vehicles or PRC companies by such means as acquisition, trust, proxy, voting rights, repurchase, convertible bonds or other arrangements. SAFE Circular 37 further requires amendment to the registration in the event of any changes with respect to the basic information of or any significant changes with respect to the special purpose vehicle. If the shareholders of the offshore holding company who are PRC residents do not complete their registration with the local SAFE branches, the PRC subsidiaries may be prohibited from distributing their profits and proceeds from any reduction in capital, share transfer or liquidation to the offshore company, and the offshore company may be restricted in its ability to contribute additional capital to its PRC subsidiaries. Moreover, failure to comply with SAFE registration and amendment requirements described above could result in liability under PRC law for evasion of applicable foreign exchange restrictions.

We will request PRC residents who we know hold direct or indirect interests in our company, if any, to make the necessary applications, filings and amendments as required under SAFE Circular 37 and other related rules. However, we may not be informed of the identities of all the PRC residents holding direct or indirect interest in our company, and we cannot provide any assurance that these PRC residents will comply with our request to make or obtain any applicable registrations or comply with other requirements under SAFE Circular 37 or other related rules. The failure or inability of our PRC resident shareholders to comply with the registration procedures set forth in these regulations may subject us to fines and legal sanctions, restrict our cross-border investment activities, limit the ability of our wholly foreign-owned subsidiaries in China to distribute dividends and the proceeds from any reduction in capital, share transfer or liquidation to us, and we may also be prohibited from injecting additional capital into these subsidiaries. Moreover, failure to comply with the various foreign exchange registration requirements described above could result in liability under PRC law for circumventing applicable foreign exchange restrictions. As a result, our business operations and our ability to distribute profits to you could be materially and adversely affected.

PRC regulations establish complex procedures for some acquisitions of Chinese companies by foreign investors, which could make it more difficult for us to pursue growth through acquisitions in China.

PRC regulations and rules concerning mergers and acquisitions including the Regulations on Mergers and Acquisitions of Domestic Companies by Foreign Investors, or the M&A Rules, and other recently adopted regulations and rules with respect to mergers and acquisitions established additional procedures and requirements that could make merger and acquisition activities by foreign investors more time consuming and complex. For example, the M&A Rules require that the MOFCOM be notified in advance of any change-of-control transaction in which a foreign investor takes control of a PRC domestic enterprise, if (i) any important industry is concerned, (ii) such transaction involves factors that have or may have impact on the national economic security, or (iii) such transaction will lead to a change in control of a domestic enterprise which holds a famous trademark or PRC time-honored brand. Moreover, according to the Anti-Monopoly Law of PRC promulgated on August 30, 2007 and the Provisions on Thresholds for Prior Notification of Concentrations of Undertakings, or the Prior Notification Rules issued by the State Council in August 2008 and amended in September 2018, the concentration of business undertakings by way of mergers, acquisitions or contractual arrangements that allow one market player to take control of or to exert decisive impact on another market player must also be notified in advance to the anti-monopoly enforcement agency of the State Council when the threshold is crossed and such concentration shall not be implemented without the clearance of prior notification. In addition, the Regulations on Implementation of Security Review System for the Merger and Acquisition of Domestic Enterprise by Foreign Investors, or the Security Review Rules issued by the MOFCOM that became effective in September 2011 specify that mergers and acquisitions by foreign investors that raise “national defense and security” concerns and mergers and acquisitions through which foreign investors may acquire the de facto control over domestic enterprises that raise “national security” concerns are subject to strict review by the MOFCOM, and the rules prohibit any activities attempting to bypass a security review by structuring the transaction through, among other things, trusts, entrustment or contractual control arrangements. In the future, we may grow our business by acquiring complementary businesses. Complying with the requirements of the above-mentioned regulations and other relevant rules to complete such

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transactions could be time consuming, and any required approval processes, including obtaining approval from the MOFCOM or its local counterparts may delay or inhibit our ability to complete such transactions. It is unclear whether our business would be deemed to be in an industry that raises “national defense and security” or “national security” concerns. However, the MOFCOM or other government agencies may publish explanations in the future determining that our business is in an industry subject to the security review, in which case our future acquisitions in the PRC, including those by way of entering into contractual control arrangements with target entities, may be closely scrutinized or prohibited. Our ability to expand our business or maintain or expand our market share through future acquisitions would as such be materially and adversely affected.

If we are classified as a PRC resident enterprise for PRC income tax purposes, such classification could result in unfavorable tax consequences to us and our non-PRC shareholders or ADS holders.

China Enterprise Income Tax Law, or the EIT Law, which was promulgated in March 2007, became effective in January 2008 and was amended in February 2017 and December 2018, and the Regulation on the Implementation of the EIT Law, effective as of January 1, 2008 and amended in April 2019, define the term “de facto management bodies” as “bodies that substantially carry out comprehensive management and control on the business operation, employees, accounts and assets of enterprises.” Under the EIT Law, an enterprise incorporated outside of PRC whose “de facto management bodies” are located in PRC is considered a “resident enterprise” and will be subject to a uniform 25% enterprise income tax, or EIT, rate on its global income. On April 22, 2009, PRC’s State Administration of Taxation, or the SAT, in the Notice Regarding the Determination of Chinese-Controlled Offshore-Incorporated Enterprises as PRC Tax Resident Enterprises on the Basis of De Facto Management Bodies, or SAT Circular 82, further specified certain criteria for the determination of what constitutes “de facto management bodies.” If all of these criteria are met, the relevant foreign enterprise may be regarded to have its “de facto management bodies” located in China and therefore be considered a PRC resident enterprise. These criteria include: (i) the enterprise’s day-to-day operational management is primarily exercised in China; (ii) decisions relating to the enterprise’s financial and human resource matters are made or subject to approval by organizations or personnel in China; (iii) the enterprise’s primary assets, accounting books and records, company seals, and board and shareholders’ meeting minutes are located or maintained in China; and (iv) 50% or more of voting board members or senior executives of the enterprise habitually reside in China. Although SAT Circular 82 only applies to foreign enterprises that are majority-owned and controlled by PRC enterprises, not those owned and controlled by foreign enterprises or individuals, the determining criteria set forth in SAT Circular 82 may be adopted by the PRC tax authorities as the test for determining whether the enterprises are PRC tax residents, regardless of whether they are majority-owned and controlled by PRC enterprises.

We believe that neither Zai Lab Limited nor any of our subsidiaries outside of China is a PRC resident enterprise for PRC tax purposes. However, the tax resident status of an enterprise is subject to determination by the PRC tax authorities, and uncertainties remain with respect to the interpretation of the term “de facto management body.” If the PRC tax authorities determine that Zai Lab Limited or any of its subsidiaries outside of China is a PRC resident enterprise for EIT purposes that entity would be subject to a 25% EIT on its global income. If such entity derives income other than dividends from its wholly-owned subsidiaries in China, a 25% EIT on its global income may increase our tax burden. Dividends paid to a PRC resident enterprise from its wholly-owned subsidiaries in China may be regarded as tax-exempt income if such dividends are deemed to be “dividends between qualified PRC resident enterprises” under the EIT Law and its implementation rules. However, we cannot assure you that such dividends will not be subject to PRC withholding tax, as the PRC tax authorities, which enforce the withholding tax, have not yet issued relevant guidance.

In addition, if Zai Lab Limited is classified as a PRC resident enterprise for PRC tax purposes, we may be required to withhold tax at a rate of 10% from dividends we pay to our shareholders, including the holders of our ADSs, that are non-resident enterprises. In addition, non-resident enterprise shareholders (including our ADS holders) may be subject to a 10% PRC withholding tax on gains realized on the sale or other disposition of ADSs or ordinary shares, if such income is treated as sourced from within China. Furthermore, gains derived by our non-PRC individual shareholders from the sale of our shares and ADSs may be subject to a 20% PRC withholding tax. It is unclear whether our non-PRC individual shareholders (including our ADS holders) would be subject to any PRC tax (including withholding tax) on dividends received by such non-PRC individual shareholders in the event we are determined to be a PRC resident enterprise. If any PRC tax were to apply to such dividends, it would generally apply at a rate of 20%. The PRC tax liability may be reduced under applicable tax treaties. However, it is unclear whether our non-PRC shareholders would be able to claim the benefits of any tax treaties between their country of tax residence and the PRC in the event that Zai Lab Limited is treated as a PRC resident enterprise.

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We may rely on dividends and other distributions on equity paid by our PRC subsidiaries to fund any cash and financing requirements we may have, and any limitation on the ability of our PRC subsidiaries to make payments to us could have a material and adverse effect on our ability to conduct our business.

We are a holding company, and we may rely on dividends and other distributions on equity paid by our PRC subsidiaries for our cash and financing requirements, including the funds necessary to pay dividends and other cash distributions to our shareholders or to service any debt we may incur. If any of our PRC subsidiaries incur debt on its own behalf in the future, the instruments governing the debt may restrict its ability to pay dividends or make other distributions to us. Under PRC laws and regulations, our PRC subsidiaries, each of which is a wholly foreign-owned enterprise may pay dividends only out of its respective accumulated profits as determined in accordance with PRC accounting standards and regulations. In addition, a wholly foreign-owned enterprise is required to set aside at least 10% of its accumulated after-tax profits each year, if any, to fund a certain statutory reserve fund, until the aggregate amount of such fund reaches 50% of its registered capital. Such reserve funds cannot be distributed to us as dividends. At its discretion, a wholly foreign-owned enterprise may allocate a portion of its after-tax profits based on PRC accounting standards to an enterprise expansion fund, or a staff welfare and bonus fund.

Our PRC subsidiaries generate primarily all of their revenue in renminbi, which is not freely convertible into other currencies. As result, any restriction on currency exchange may limit the ability of our PRC subsidiaries to use their renminbi revenues to pay dividends to us.

In response to the persistent capital outflow in China and renminbi’s depreciation against U.S. dollar in the fourth quarter of 2016, the People’s Bank of China, or PBOC, and the SAFE have promulgated a series of capital control measure in early 2017, including stricter vetting procedures for domestic companies to remit foreign currency for overseas investments, dividends payments and shareholder loan repayments.

The PRC government may continue to strengthen its capital controls, and more restrictions and substantial vetting process may be put forward by SAFE for cross-border transactions falling under both the current account and the capital account. Any limitation on the ability of our PRC subsidiaries to pay dividends or make other kinds of payments to us could materially and adversely limit our ability to grow, make investments or acquisitions that could be beneficial to our business, pay dividends, or otherwise fund and conduct our business.

We and our shareholders face uncertainties in the PRC with respect to indirect transfers of equity interests in PRC resident enterprises.

The indirect transfer of equity interest in PRC resident enterprises by a non-PRC resident enterprise, or Indirect Transfer, is potentially subject to income tax in China at a rate of 10% on the gain if such transfer is considered as not having a commercial purpose and is carried out for tax avoidance. The SAT has issued several rules and notices to tighten the scrutiny over acquisition transactions in recent years. SAT Circular 7 sets out the scope of Indirect Transfers, which includes any changes in the shareholder’s ownership of a foreign enterprise holding PRC assets directly or indirectly in the course of a group’s overseas restructuring, and the factors to consider in determining whether an Indirect Transfer has a commercial purpose. An Indirect Transfer satisfying all the following criteria will be deemed to lack a bona fide commercial purpose and be taxable under PRC laws: (i) 75% or more of the equity value of the intermediary enterprise being transferred is derived directly or indirectly from the PRC taxable assets; (ii) at any time during the one-year period before the indirect transfer, 90% or more of the asset value of the intermediary enterprise (excluding cash) is comprised directly or indirectly of investments in China, or 90% or more of its income is derived directly or indirectly from China; (iii) the functions performed and risks assumed by the intermediary enterprise and any of its subsidiaries that directly or indirectly hold the PRC taxable assets are limited and are insufficient to prove their economic substance; and (iv) the non-PRC tax payable on the gain derived from the indirect transfer of the PRC taxable assets is lower than the potential PRC income tax on the direct transfer of such assets. Nevertheless, a non-resident enterprise’s buying and selling shares or ADSs of the same listed foreign enterprise on the public market will fall under the safe harbor available under SAT Circular 7 and will not be subject to PRC tax pursuant to SAT Circular 7. Under SAT Circular 7, the entities or individuals obligated to pay the transfer price to the transferor shall be the withholding agent and shall withhold the PRC tax from the transfer price. If the withholding agent fails to do so, the transferor shall report to and pay the PRC tax to the PRC tax authorities. In case neither the withholding agent nor the transferor complies with the obligations under SAT Circular 7, other than imposing penalties such as late payment interest on the transferors, the tax authority may also hold the withholding agent liable and impose a penalty of 50% to 300% of the unpaid tax on the withholding agent. The penalty imposed on the withholding agent may be reduced or waived if the withholding agent has submitted the relevant materials in connection with the indirect transfer to the PRC tax authorities in accordance with SAT Circular 7.

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However, as these rules and notices are relatively new and there is a lack of clear statutory interpretation, we face uncertainties regarding the reporting required for and impact on future private equity financing transactions, share exchange or other transactions involving the transfer of shares in our company by investors that are non-PRC resident enterprises, or the sale or purchase of shares in other non-PRC resident companies or other taxable assets by us. Our company and other non-resident enterprises in our group may be subject to filing obligations or being taxed if our company and other non-resident enterprises in our group are transferors in such transactions, and may be subject to withholding obligations if our company and other non-resident enterprises in our group are transferees in such transactions. For the transfer of shares in our company by investors that are non-PRC resident enterprises, our PRC subsidiaries may be requested to assist in the filing under the rules and notices. As a result, we may be required to expend valuable resources to comply with these rules and notices or to request the relevant transferors from whom we purchase taxable assets to comply, or to establish that our company and other non-resident enterprises in our group should not be taxed under these rules and notices, which may have a material adverse effect on our financial condition and results of operations. There is no assurance that the tax authorities will not apply the rules and notices to our offshore restructuring transactions where non-PRC residents were involved if any of such transactions were determined by the tax authorities to lack reasonable commercial purpose. As a result, we and our non-PRC resident investors may be at risk of being taxed under these rules and notices and may be required to comply with or to establish that we should not be taxed under such rules and notices, which may have a material adverse effect on our financial condition and results of operations or such non-PRC resident investors’ investments in us. We may conduct acquisition transactions in the future. We cannot assure you that the PRC tax authorities will not, at their discretion, adjust any capital gains and impose tax return filing obligations on us or require us to provide assistance for the investigation of PRC tax authorities with respect thereto. Heightened scrutiny over acquisition transactions by the PRC tax authorities may have a negative impact on potential acquisitions we may pursue in the future.

Any failure to comply with PRC regulations regarding the registration requirements for our employee equity incentive plans may subject us to fines and other legal or administrative sanctions, which could adversely affect our business, financial condition and results of operations.

In February 2012, the SAFE promulgated the Notices on Issues Concerning the Foreign Exchange Administration for Domestic Individuals Participating in Stock Incentive Plans of Overseas Publicly Listed Companies, or the Stock Option Rules. In accordance with the Stock Option Rules and relevant rules and regulations, PRC citizens or non-PRC citizens residing in China for a continuous period of not less than one year, who participate in any stock incentive plan of an overseas publicly listed company, subject to a few exceptions, are required to register with SAFE through a domestic qualified agent, which could be a PRC subsidiary of such overseas listed company, and complete certain procedures. We and our employees who are PRC citizens or who reside in China for a continuous period of not less than one year and who participate in our stock incentive plan will be subject to such regulation. We plan to assist our employees to register their share options or shares. However, any failure of our PRC individual beneficial owners and holders of share options or shares to comply with the SAFE registration requirements may subject them to fines and legal sanctions and may limit the ability of our PRC subsidiaries to distribute dividends to us. We also face regulatory uncertainties that could restrict our ability to adopt additional incentive plans for our directors and employees under PRC law.

Proceedings brought by the SEC against the Big Four PRC-based accounting firms, including our independent registered public accounting firm, could result in our inability to file future financial statements in compliance with the requirements of the Exchange Act.

In December 2012, the SEC instituted administrative proceedings under Rule 102(e)(1)(iii) of the SEC’s Rules of Practice against the Big Four PRC-based accounting firms, including our independent registered public accounting firm, alleging that these firms had violated U.S. securities laws and the SEC’s rules and regulations thereunder by failing to provide to the SEC the firms’ audit work papers with respect to certain PRC-based companies under the SEC’s investigation. On January 22, 2014, the administrative law judge, or the ALJ, presiding over the matter rendered an initial decision that each of the firms had violated the SEC’s rules of practice by failing to produce audit workpapers to the SEC. The initial decision censured each of the firms and barred them from practicing before the SEC for a period of six months. On February 12, 2014, the Big Four PRC-based accounting firms appealed the ALJ’s initial decision to the SEC. On February 6, 2015, the four China-based accounting firms each agreed to a censure and to pay a fine to the SEC to settle the dispute and avoid suspension of their ability to practice before the SEC and audit U.S.-listed companies. The settlement required the firms to follow detailed procedures and to seek to provide the SEC with access to Chinese firms’ audit documents via the CSRC, in response to future document requests by the SEC made through the CSRC. If the Big Four PRC-based accounting firms fail to comply with the documentation production procedures that are in the settlement agreement or if there is a failure of the process between the SEC and the CSRC, the SEC could restart the proceedings against the firms.

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In the event that the SEC restarts the administrative proceedings, depending upon the final outcome, listed companies in the United States with major PRC operations may find it difficult or impossible to retain auditors in respect of their operations in the PRC, which could result in financial statements being determined to not be in compliance with the requirements of the Exchange Act, including possible delisting. Moreover, any negative news about the proceedings against these audit firms may cause investor uncertainty regarding PRC-based, United States-listed companies and the market price of our ADSs may be adversely affected.

If the accounting firms are subject to additional remedial measures, our ability to file our financial statements in compliance with SEC requirements could be impacted. A determination that we have not timely filed financial statements in compliance with SEC requirements would substantially reduce or effectively terminate the trading of our ADSs in the United States.

Certain of our investments may be subject to review from the Committee on Foreign Investment in the United States, or CFIUS, which may delay or block a transaction from closing.

The U.S. Congress has passed legislation that will expand the jurisdiction and powers of the CFIUS, the U.S. interagency committee that conducts national security reviews of foreign investment. President Trump signed the Foreign Investment Risk Review Modernization Act (FIRRMA) in August 2018. Pursuant to FIRRMA, investments in companies that deal in “critical technology” are subject to filing requirements and, in some instances, review and approval by CFIUS. The term “critical technology” includes, among others, technology subject to U.S. export controls and certain “emerging and foundational technology,” a term that is still being defined but that is expected to include a range of U.S. biotechnology. If an investment by a foreign entity in a U.S. business dealing in “critical technology” meets certain thresholds, a filing with CFIUS is mandatory.

Accordingly, to the extent the U.S. portion of our business decides to take investments from foreign persons, such investments could be subject to CFIUS jurisdiction. To date, none of our investments have been subject to CFIUS review but, depending on the particulars of ongoing or future investments, we may be obligated to secure CFIUS approval before closing, which could delay the time period between signing and closing. If we determine that a CFIUS filing is not mandatory (or otherwise advisable), there is a risk that CFIUS could initiate its own review, if it determines that the transaction is subject to its jurisdiction. If an investment raises significant national security concerns, CFIUS has the authority to impose mitigation conditions or recommend that the President block a transaction.

Risks Related to Intellectual Property

If we are unable to obtain and maintain patent protection for our products and drug candidates through intellectual property rights, or if the scope of such intellectual property rights obtained is not sufficiently broad, third parties may compete directly against us.

Our success depends, in part, on our ability to protect our products and drug candidates from competition by obtaining, maintaining and enforcing our intellectual property rights, including patent rights. We seek to protect the products and drug candidates and technology that we consider commercially important by filing PRC and international patent applications, relying on trade secrets or pharmaceutical regulatory protection or employing a combination of these methods. We also seek to protect our proprietary position by in-licensing intellectual property relating to our technology and drug candidates. We do not own or exclusively license any issued patents with respect to certain of our products and drug candidates in all territories in which we plan to commercialize our products and drug candidates. For example, we do not own or exclusively license any issued patents covering ZEJULA in Hong Kong or Macau. We do not own or exclusively license any issued patents covering margetuximab, MGD-013 and a pre-clinical multi-specific TRIDENT molecule in Macau or Taiwan, but we do non-exclusively in-license issued patents in China and Hong Kong and pending patent applications in China, Hong Kong or Taiwan covering them. We do not own or exclusively license any issued patents or pending patent applications covering Optune in Hong Kong, Macau, or Taiwan, but we do exclusively license issued patents and pending patent applications covering Optune in China. We do not own or exclusively license any issued patents covering INCMGA0012 (PD-1), but we do in-license two pending patent applications relating to INCMGA0012 (PD-1) in China, 2 in Taiwan and 1 in Hong Kong. We in-license 1 issued patent in China and 1 in Taiwan, but we also in-license 1 pending patent application relating to EXT2514 in China, 1 in Hong Kong, 1 in Taiwan. We cannot predict whether such patent applications or any of our other owned or in-licensed pending patent applications will result in the issuance of any patents that effectively protect our products and drug candidates. If we or our licensors are unable to obtain or maintain patent protection with respect to our products or drug candidates and technology we develop, our business, financial condition, results of operations, and prospects could be materially harmed.

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The patent prosecution process is expensive, time-consuming and complex, and we may not be able to file, prosecute, maintain, enforce or license all necessary or desirable patent applications at a reasonable cost or in a timely manner. In addition, our license and intellectual property-related agreements may not provide us with exclusive rights to use our in-licensed intellectual property rights relating to the applicable products and drug candidates in all relevant fields of use and in all territories in which we may wish to develop or commercialize our technology and products in the future. For example, under our agreements with GSK for ZEJULA, our licenses are limited to China, Hong Kong, and Macau. In the case of our agreements with Novocure for Optune, Paratek for omadacycline (ZL-2401), Five Prime for bemarituzumab (FPA144), and MacroGenics for margetuximab, MGD-013 and a pre-clinical multi-specific TRIDENT molecule, our licenses are limited to China, Hong Kong, Macau, and Taiwan. Also, in the case of our agreement with Entasis for durlobactam, our license is limited to China, Hong Kong, Macau, Taiwan, Korea, Vietnam, Thailand, Cambodia, Laos, Malaysia, Indonesia, the Philippines, Singapore, Australia, New Zealand and Japan. As a result, we may not be able to prevent competitors from developing and commercializing competitive products in all such fields and territories. In the case of our agreement with Deciphera for ripretinib, our license is limited to China, Hong Kong, Macau and Taiwan. In the case of our agreement with Incyte for INCMGA0012 (PD-1) , our license s are limited to China, Hong Kong, Macau and Taiwan.

Patents may be invalidated and patent applications, including our in-licensed patent application relating to FP144, Optune, margetuximab, MGD-013, EXT2514, a pre-clinical multi-specific TRIDENT molecule or INCMGA0012 (PD-1) as well as Regeneron’s patents relating to REGN1979, may not be granted for a number of reasons, including known or unknown prior art, deficiencies in the patent application or the lack of novelty of the underlying invention or technology. It is also possible that we will fail to identify patentable aspects of our research and development output in time to obtain patent protection. Although we enter into non-disclosure and confidentiality agreements with parties who have access to confidential or patentable aspects of our research and development output, such as our employees, corporate collaborators, outside scientific collaborators, contract manufacturers, consultants, advisors and any other third parties, any of these parties may breach such agreements and disclose such output before a patent application is filed, thereby jeopardizing our ability to seek patent protection. In addition, publications of discoveries in the scientific literature often lag behind the actual discoveries, and patent applications in the United States and other jurisdictions are typically not published until 18 months after filing, or in some cases, not at all. Therefore, we cannot be certain that we or our licensors were the first to make the inventions claimed in our owned or in-licensed patents or pending patent applications or that we or our licensors were the first to file for patent protection of such inventions. Furthermore, the PRC and, recently, the United States have adopted the “first-to-file” system under which whoever first files a patent application will be awarded the patent if all other patentability requirements are met. Under the first-to-file system, third parties may be granted a patent relating to a technology, which we invented.

In addition, under PRC Patent Law, any organization or individual that applies for a patent in a foreign country for an invention or utility model accomplished in China is required to report to the State Intellectual Property Office, or SIPO, for confidentiality examination. Otherwise, if an application is later filed in China, the patent right will not be granted. Moreover, even if patents do grant from any of the applications, the grant of a patent is not conclusive as to its scope, validity or enforceability.

The coverage claimed in a patent application can be significantly reduced before the patent is issued, and its scope can be reinterpreted after issuance. Even if patent applications we license or own currently or in the future issue as patents, they may not issue in a form that will provide us with any meaningful protection, prevent competitors or other third parties from competing with us, or otherwise provide us with any competitive advantage. In addition, the patent position of biotechnology and pharmaceutical companies generally is highly uncertain, involves complex legal and factual questions, and has been the subject of much litigation in recent years. As a result, the issuance, scope, validity, enforceability and commercial value of our patent rights are highly uncertain.

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The issuance of a patent is not conclusive as to its inventorship, scope, validity or enforceability, and our patents may be challenged in the courts or patent offices in the PRC, United States and abroad. We and our licensors and collaboration partners may be subject to a third-party preissuance submission of prior art to the United States Patent and Trademark Office, or USPTO, or become involved in opposition, derivation, revocation, re-examination, post-grant and inter partes review, or interference proceedings or similar proceedings in foreign jurisdictions challenging our patent rights or the patent rights of others. An adverse determination in any such submission, proceeding or litigation could reduce the scope of, or invalidate, our owned or in-licensed patent rights, allow third parties to commercialize our technology, products or drug candidates and compete directly with us without payment to us, or result in our inability to manufacture or commercialize products or drug candidates without infringing, misappropriating or otherwise violating third-party patent rights. Moreover, we, or one of our licensors or collaboration partners, may have to participate in interference proceedings declared by the USPTO to determine priority of invention or in post-grant challenge proceedings, such as oppositions in a foreign patent office, that challenge the priority of our or our licensor’s or collaboration partner’s invention or other features of patentability of our owned or in-licensed patents and patent applications. Such challenges may result in loss of patent rights, loss of exclusivity, or in patent claims being narrowed, invalidated, or held unenforceable, which could limit our ability to stop others from using or commercializing similar or identical technology and products, limit the duration of the patent protection of our technology, or limit the price at which we can sell our products and drug candidates. Such proceedings also may result in substantial costs and require significant time from our scientists and management, even if the eventual outcome is favorable to us. Consequently, we do not know whether any of our technology, products or drug candidates will be protectable or remain protected by valid and enforceable patents. Our competitors or other third parties may be able to circumvent our owned or in-licensed patents by developing similar or alternative technologies or products in a non-infringing manner.

Furthermore, the terms of patents are finite. The patents we own or in-license and the patents that may issue from our currently pending owned and in-licensed patent applications generally have a 20-year protection period starting from such patents and patent applications’ earliest filing date. Given the amount of time required for the development, testing and regulatory review of products and new drug candidates, patents protecting such products and drug candidates might expire before or shortly after such products or drug candidates are commercialized. As a result, our owned or in-licensed patents and patent applications may not provide us with sufficient rights to exclude others from commercializing products similar or identical to ours. Moreover, some of our patents and patent applications are, and may in the future be, co-owned with third parties. If we are unable to obtain an exclusive license to any such third party co-owners’ interest in such patents or patent applications, such co-owners may be able to license their rights to other third parties, including our competitors, and our competitors could market competing products and technology. In addition, we may need the cooperation of any such co-owners of our patents in order to enforce such patents against third parties, and such cooperation may not be provided to us. Any of the foregoing could have a material adverse effect on our competitive position, business, financial conditions, results of operations and prospects.

Our owned or in-licensed patents could be found invalid or unenforceable if challenged in court or before the USPTO or comparable foreign authority.

We or our licensors or collaboration partners may become involved in patent litigation against third parties to enforce owned or in-licensed patent rights, to invalidate patents held by such third parties, or to defend against such claims. A court may refuse to stop the other party from using the technology at issue on the grounds that patents owned or in-licensed by us, our licensors or our collaboration partners do not cover the third-party technology in question. Further, such third parties could counterclaim that we infringe, misappropriate or otherwise violate their intellectual property or that a patent we or our licensors or collaboration partners have asserted against them is invalid or unenforceable. In patent litigation, defendant counterclaims challenging the validity, enforceability or scope of asserted patents are commonplace and there are numerous grounds upon which a third party can assert invalidity or unenforceability of a patent. In addition, third parties may initiate legal proceedings before administrative bodies in the United States or abroad, even outside the context of litigation, against us or our licensors with respect to our owned or in-licensed intellectual property to assert such challenges to such intellectual property rights. Such mechanisms include re-examination, inter partes review, post-grant review, interference proceedings, derivation proceedings and equivalent proceedings in foreign jurisdictions (e.g., opposition proceedings). Such proceedings could result in revocation, cancellation or amendment to our patents in such a way that they no longer cover and protect our products and drug candidates.

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The outcome of any such proceeding is generally unpredictable. Grounds for a validity challenge could be, among other things, an alleged failure to meet any of several statutory requirements, including lack of novelty, obviousness, lack of written description or non-enablement. Grounds for an unenforceability assertion could be, among other things, an allegation that someone connected with prosecution of the patent withheld relevant information or made a misleading statement during prosecution. It is possible that prior art of which we and the patent examiner were unaware during prosecution exists, which could render our patents invalid. Moreover, it is also possible that prior art may exist that we are aware of but do not believe is relevant to our current or future patents, but that could nevertheless be determined to render our patents invalid. Even if we are successful in defending against such challenges, the cost to us of any patent litigation or similar proceeding could be substantial, and it may consume significant management and other personnel time. We do not maintain insurance to cover intellectual property infringement, misappropriation or violation.

An adverse result in any litigation or other intellectual property proceeding could put one or more of our patents at risk of being invalidated, rendered unenforceable or interpreted narrowly. If a defendant were to prevail on a legal assertion of invalidity and/or unenforceability of our patents covering one or more of our products or drug candidates, we would lose at least part, and perhaps all, of the patent protection covering such products or drug candidates. Competing products or drugs may also be sold in other countries in which our patent coverage might not exist or be as strong. If we lose a foreign patent lawsuit, alleging our infringement of a competitor’s patents, we could be prevented from marketing our products or drugs in one or more foreign countries. Any of these outcomes would have a materially adverse effect on our business, financial condition, results of operations and prospects.

We may not be able to protect our intellectual property in the PRC.

The validity, enforceability and scope of protection available under the relevant intellectual property laws in the PRC are uncertain and still evolving. Implementation and enforcement of PRC intellectual property-related laws have historically been deficient and ineffective. Accordingly, intellectual property and confidentiality legal regimes in China may not afford protection to the same extent as in the United States or other countries. Policing unauthorized use of proprietary technology is difficult and expensive, and we may need to resort to litigation to enforce or defend patents issued to us or our licensors to determine the enforceability, scope and validity of our proprietary rights or those of others. As noted above, we may need to rely on our licensors to enforce and defend our technologies. The experience and capabilities of PRC courts in handling intellectual property litigation varies, and outcomes are unpredictable. Further, such litigation may require a significant expenditure of cash and may divert management’s attention from our operations, which could harm our business, financial condition and results of operations. An adverse determination in any such litigation could materially impair our intellectual property rights and may harm our business, prospects and reputation.

We may not be able to protect our intellectual property and proprietary rights throughout the world.

Filing, prosecuting, maintaining and defending patents on products and drug candidates in all countries throughout the world would be prohibitively expensive, and the laws of foreign countries may not protect our rights to the same extent as the laws of the United States. Consequently, we may not be able to prevent third parties from practicing our inventions in all countries outside the United States or PRC or from selling or importing products made using our inventions in and into the United States, the PRC or other jurisdictions. Competitors may use our technologies in jurisdictions where we have not obtained patent protection to develop their own competing products and, further, may export otherwise infringing products to territories where we have patent protection or licenses but enforcement is not as strong as that in the United States. These products may compete with our products, and our patents or other intellectual property rights may not be effective or sufficient to prevent them from competing.

Many companies have encountered significant problems in protecting and defending intellectual property rights in foreign jurisdictions, including China. The legal systems of certain countries, particularly certain developing countries, do not favor the enforcement of patents, trade secrets, and other intellectual property protection, particularly those relating to biotechnology products, which could make it difficult for us to stop the infringement of our patents or marketing of competing products in violation of our intellectual property and proprietary rights generally. Proceedings to enforce our intellectual property and proprietary rights in foreign jurisdictions could result in substantial costs and divert our efforts and attention from other aspects of our business, could put our patents at risk of being invalidated or interpreted narrowly, could put our patent applications at risk of not issuing, and could provoke third parties to assert claims against us. We may not prevail in any lawsuits that we initiate, and the damages or other remedies awarded, if any, may not be commercially meaningful. Accordingly, our efforts to enforce our intellectual property and proprietary rights around the world may be inadequate to obtain a significant commercial advantage from the intellectual property that we develop or license.

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Furthermore, many countries have compulsory licensing laws under which a patent owner may be compelled to grant licenses to third parties. In addition, many countries limit the enforceability of patents against government agencies or government contractors. In these countries, the patent owner may have limited remedies, which could materially diminish the value of such patent. If we or any of our licensors are forced to grant a license to third parties with respect to any patents relevant to our business, our competitive position may be impaired, and our business, financial condition, results of operations and prospects may be adversely affected.

Developments in patent law could have a negative impact on our business.

Changes in either the patent laws or interpretation of the patent laws in the United States, PRC and other jurisdictions could increase the uncertainties and costs surrounding the prosecution of patent applications and the enforcement or defense of issued patents, including changing the standards of patentability, and any such changes could have a negative impact on our business. For example, in the United States, the Leahy-Smith America Invents Act, or the America Invents Act, which was signed into law in September 2011, includes a number of significant changes to U.S. patent law. These changes include a transition from a “first-to-invent” system to a “first-to-file” system as of March 2013, changes to the way issued patents are challenged, and changes to the way patent applications are disputed during the examination process. These include allowing third party submission of prior art to the USPTO during patent prosecution and additional procedures to attack the validity of a patent by USPTO administered post grant proceedings, including post grant review, inter partes review, and derivation proceedings. As a result of these changes, patent law in the United States may favor larger and more established companies that have greater resources to devote to patent application filing and prosecution. The USPTO has developed new and untested regulations and procedures to govern the full implementation of the America Invents Act, and many of the substantive changes to patent law associated with the America Invents Act, and, in particular, the first-to-file provisions became effective in March 2013. Substantive changes to patent law associated with the America Invents Act may affect our ability to obtain patents, and if obtained, to enforce or defend them. Accordingly, it is not clear what, if any, impact the America Invents Act will have on the cost of prosecuting our patent applications and our ability to obtain patents based on our discoveries and to enforce or defend any patents that may issue from our patent applications, all of which could have a material adverse effect on our business, financial condition, results of operations and prospects.

In addition, the patent positions of companies in the development and commercialization of biologics and pharmaceuticals are particularly uncertain. Recent U.S. Supreme Court rulings have narrowed the scope of patent protection available in certain circumstances and weakened the rights of patent owners in certain situations. This combination of events has created uncertainty with respect to the validity and enforceability of patents, once obtained. Depending on future actions by the U.S. Congress, the federal courts and the USPTO, the laws and regulations governing patents could change in unpredictable ways that could have a material adverse effect on our existing patent portfolio and our ability to protect and enforce our intellectual property in the future.

If we are unable to maintain the confidentiality of our trade secrets, our business and competitive position may be harmed.

In addition to the protection afforded by registered patents and pending patent applications, we rely upon unpatented trade secret protection, unpatented know-how and continuing technological innovation to develop and maintain our competitive position. However, trade secrets and know-how can be difficult to protect. We also seek to protect our proprietary technology and processes, in part, by entering into confidentiality agreements with parties that have access to them, such as our partners, collaborators, scientific advisors, employees, consultants and other third parties, and invention assignment agreements with our consultants and employees. We cannot guarantee that we have entered into such agreements with each party that may have or have had access to our trade secrets or proprietary technology and processes. We may not be able to prevent the unauthorized disclosure or use of our technical know-how or other trade secrets by the parties to these agreements, however, despite the existence generally of confidentiality agreements and other contractual restrictions. If any of the partners, collaborators, scientific advisors, employees and consultants who are parties to these agreements breaches or violates the terms of any of these agreements or otherwise discloses our proprietary information, we may not have adequate remedies for any such breach or violation, and we could lose our trade secrets as a result. Enforcing a claim that a third party illegally disclosed or misappropriated our trade secrets, including through intellectual property litigations or other proceedings, is difficult, expensive and time consuming, and the outcome is unpredictable. In addition, courts in China and other jurisdictions inside and outside the United States are less prepared, less willing or unwilling to protect trade secrets.

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Our trade secrets could otherwise become known or be independently discovered by our competitors or other third parties. For example, competitors could purchase our products and drug candidates and attempt to replicate some or all of the competitive advantages we derive from our development efforts, willfully infringe, misappropriate or otherwise violate our intellectual property rights, design around our intellectual property protecting such technology or develop their own competitive technologies that fall outside of our intellectual property rights. If any of our trade secrets were to be disclosed or independently developed by a competitor, we would have no right to prevent them, or others to whom they communicate it, from using that technology or information to compete against us, which may have a material adverse effect on our business, prospects, financial condition and results of operations.

If our products or drug candidates infringe, misappropriate or otherwise violate the intellectual property rights of third parties, we may incur substantial liabilities, and we may be unable to sell or commercialize these products and drug candidates.

Our commercial success depends significantly on our ability to develop, manufacture, market and sell our products and drug candidates and use our proprietary technologies without infringing, misappropriating or otherwise violating the patents and other proprietary rights of third parties. The biotechnology and pharmaceutical industries are characterized by extensive litigation regarding patents and other intellectual property rights. In the PRC and the United States, invention patent applications are generally maintained in confidence until their publication 18 months from the filing date. The publication of discoveries in the scientific or patent literature frequently occurs substantially later than the date on which the underlying discoveries were made and invention patent applications are filed. Even after reasonable investigation, we may not know with certainty whether any third-party may have filed a patent application without our knowledge while we are still developing or producing that product. We may become party to, or threatened with, adversarial proceedings or litigation regarding intellectual property rights with respect to our technology and any products or drug candidates we may develop, including interference proceedings, post-grant review, inter partes review and derivation proceedings before the USPTO and similar proceedings in foreign jurisdictions.

Third parties may assert infringement claims against us based on existing patents or patents that may be granted in the future, regardless of their merit. Even if we believe third-party intellectual property claims are without merit, there is no assurance that a court would find in our favor on questions of infringement, validity, enforceability or priority. A court of competent jurisdiction could hold that these third-party patents are valid, enforceable and infringed, which could materially and adversely affect our ability to commercialize any products or drug candidates we may develop and any other products, drug candidates or technologies covered by the asserted third-party patents. In order to successfully challenge the validity of any such U.S. patent in federal court, we would need to overcome a presumption of validity. There is no assurance that a court of competent jurisdiction would invalidate the claims of any such U.S. patent.

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Claims that we have misappropriated the confidential information or trade secrets of third parties could have a similar material adverse effect on our business, financial condition, results of operations, and prospects. Even if we are successful in such litigations or administrative proceedings, such litigations and proceedings may be costly and could result in a substantial diversion of management resources. Any of the foregoing may have a material adverse effect on our business, prospects, financial condition and results of operations.

Intellectual property litigation and proceedings could cause us to spend substantial resources and distract our personnel from their normal responsibilities.

Even if resolved in our favor, litigation or other legal proceedings relating to our, our licensor’s or other third parties’ intellectual property claims may cause us to incur significant expenses and could distract our personnel from their normal responsibilities. In addition, there could be public announcements of the results of hearings, motions, or other interim proceedings or developments, and if securities analysts or investors perceive these results to be negative, it could have a substantial adverse effect on the price of our common stock. Such litigation or proceedings could substantially increase our operating losses and reduce the resources available for development activities or any future sales, marketing, or distribution activities. We may not have sufficient financial or other resources to conduct such litigation or proceedings adequately. Some of our competitors may be able to sustain the costs of such litigation or proceedings more effectively than we can because of their greater financial resources and more mature and developed intellectual property portfolios. Uncertainties resulting from the initiation and continuation of patent litigation or other proceedings could have a material adverse effect on our ability to compete in the marketplace.

We may be subject to claims that we or our employees, consultants or advisors have wrongfully used or disclosed alleged trade secrets of competitors or their current or former employers or are in breach of non-competition or non-solicitation agreements with competitors or other third parties.

We could in the future be subject to claims that we or our employees, consultants or advisors have inadvertently or otherwise used or disclosed alleged trade secrets or other proprietary information of current or former employers, competitors or other third parties. Many of our employees, consultants and advisors are currently or were previously employed at universities or other biotechnology or pharmaceutical companies, including our competitors or potential competitors. Although we try to ensure that our employees and consultants do not improperly use the intellectual property, proprietary information, know-how or trade secrets of others in their work for us, we may be subject to claims that we or these individuals have breach the terms of his or her non-competition or non-solicitation agreement, or that we or these individuals have, inadvertently or otherwise, used or disclosed the alleged trade secrets or other proprietary information of a current or former employer, competitor or other third parties.

Litigation may be necessary to defend against these claims. Even if we are successful in defending against these claims, litigation could result in substantial costs and could be a distraction to management and research personnel. If our defenses to these claims fail, in addition to requiring us to pay monetary damages, a court could prohibit us from using technologies or features that are essential to our products and drug candidates, if such technologies or features are found to incorporate or be derived from the trade secrets or other proprietary information of the former employers. An inability to incorporate such technologies or features would have a material adverse effect on our business and may prevent us from successfully commercializing our products and drug candidates. In addition, we may lose valuable intellectual property rights or personnel as a result of such claims. Moreover, any such litigation or the threat thereof may adversely affect our ability to hire employees or contract with independent sales representatives. A loss of key personnel or their work product could hamper or prevent our ability to commercialize our products and drug candidates, which would have a material adverse effect on our business, results of operations and financial condition.

In addition, while it is our policy to require our employees and contractors who may be involved in the conception or development of intellectual property to execute agreements assigning such intellectual property to us, we may be unsuccessful in executing such an agreement with each party who, in fact, conceives or develops intellectual property that we regard as our own. The assignment of intellectual property rights may not be self-executing, or the assignment agreements may be breached, and we may be forced to bring claims against third parties, or defend claims that they may bring against us, to determine the ownership of what we regard as our intellectual property. Such claims could have a material adverse effect on our business, financial condition, results of operations and prospects.

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We may not be successful in obtaining necessary intellectual property rights to drug candidates for our development pipeline through acquisitions and in-licenses. 

Although we also intend to develop drug candidates through our own internal research, our near-term business model is predicated, in large part, on our ability to successfully identify and acquire or in-license drug candidates to grow our drug candidate pipeline. However, we may be unable to acquire or in-license intellectual property rights relating to, or necessary for, any such drug candidates from third parties on commercially reasonable terms or at all, including because we are focusing on specific areas of care such as oncology and inflammatory and infectious diseases. In that event, we may be unable to develop or commercialize such drug candidates. We may also be unable to identify drug candidates that we believe are an appropriate strategic fit for our company and intellectual property relating to, or necessary for, such drug candidates. Any of the foregoing could have a materially adverse effect on our business, financial condition, results of operations and prospects.

The in-licensing and acquisition of third-party intellectual property rights for drug candidates is a competitive area, and a number of more established companies are also pursuing strategies to in-license or acquire third-party intellectual property rights for drug candidates that we may consider attractive or necessary. These established companies may have a competitive advantage over us due to their size, cash resources and greater clinical development and commercialization capabilities. Furthermore, companies that perceive us to be a competitor may be unwilling to assign or license rights to us. If we are unable to successfully obtain rights to suitable drug candidates, our business, financial condition, results of operations and prospects for growth could suffer.

In addition, we expect that competition for the in-licensing or acquisition of third-party intellectual property rights for drug candidates that are attractive to us may increase in the future, which may mean fewer suitable opportunities for us as well as higher acquisition or licensing costs. We may be unable to in-license or acquire the third-party intellectual property rights for drug candidates on terms that would allow us to make an appropriate return on our investment.

If we do not obtain patent term extension and data exclusivity for our products or any drug candidates we may develop, our business may be materially harmed.

Depending upon the timing, duration and specifics of any FDA marketing approval of our products or any drug candidates we may develop, one or more of our owned or in-licensed U.S. patents may be eligible for limited patent term extension under the Drug Price Competition and Patent Term Restoration Action of 1984, or Hatch Waxman Amendments. The Hatch Waxman Amendments permit a patent extension term of up to five years as compensation for patent term lost during the FDA regulatory review process. A patent term extension cannot extend the remaining term of a patent beyond a total of 14 years from the date of product approval, only one patent may be extended and only those claims covering the approved drug, a method for using it, or a method for manufacturing it may be extended. However, we may not be granted an extension because of, for example, failing to exercise due diligence during the testing phase or regulatory review process, failing to apply within applicable deadlines, failing to apply prior to expiration of relevant patents, or otherwise failing to satisfy applicable requirements. Moreover, the applicable time period or the scope of patent protection afforded could be less than we request. The PRC has not established a patent term extension system, but the government proposed to grant patent term extension to new drugs that will be marketed in and outside China for up to 5 years.

In China, there is currently no effective law or regulation providing for patent term extension, patent linkage, or data exclusivity. Therefore, a lower-cost generic or biosimilar drug can emerge onto the market more quickly. Chinese regulators have set forth a framework for integrating patent linkage and data exclusivity into the Chinese regulatory regime and for establishing a pilot program for patent term extension. To be implemented, this framework will require promulgation of laws, regulations and detailed implementation measures. To date, no laws, regulations or implementation measures have been promulgated and become effective. Consequently, the absence of currently effective laws and regulations on patent linkage, patent term extension and data exclusivity or the cancellation of the currently effective five-year administrative exclusivity for domestically manufactured new drugs could result in much weaker protection for us against generic competition in China. For instance, the patents we have in China are not yet eligible to be extended for patent term lost during clinical trials and the regulatory review process. If we are unable to obtain patent term extension or term of any such extension is less than we request, our competitors may obtain approval of competing products following our patent expiration, and our business, financial condition, results of operations, and prospects could be materially harmed.

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Obtaining and maintaining our patent protection depends on compliance with various procedural, document submission, fee payment, and other requirements imposed by government patent agencies, and our patent protection could be reduced or eliminated for non-compliance with these requirements.

Periodic maintenance fees, renewal fees, annuity fees, and various other government fees on patents and applications will be due to be paid to the USPTO and various government patent agencies outside of the United States over the lifetime of our owned or licensed patents and applications. In certain circumstances, we rely on our licensing partners to pay these fees due to U.S. and non-U.S. patent agencies. The USPTO and various non-U.S. government agencies require compliance with several procedural, documentary, fee payment, and other similar provisions during the patent application process. We are also dependent on our licensors to take the necessary action to comply with these requirements with respect to our licensed intellectual property. In some cases, an inadvertent lapse can be cured by payment of a late fee or by other means in accordance with the applicable rules. There are situations, however, in which non-compliance can result in abandonment or lapse of the patent or patent application, resulting in a partial or complete loss of patent rights in the relevant jurisdiction. In such an event, potential competitors might be able to enter the market with similar or identical products or technology, which could have a material adverse effect on our business, financial condition, results of operations, and prospects.

Intellectual property rights do not necessarily address all potential threats.

The degree of future protection afforded by our intellectual property rights is uncertain because intellectual property rights have limitations and may not adequately protect our business or permit us to maintain our competitive advantage. For example:

Should any of these events occur, they could have a material adverse effect on our business, financial condition, results of operations and prospects.

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Risks Related to Our ADSs

We may be at an increased risk of securities class action litigation.

Historically, securities class action litigation has often been brought against a company following a decline in the market price of its securities. This risk is especially relevant for us because biotechnology and biopharmaceutical companies have experienced significant share price volatility in recent years. If we were to be sued, it could result in substantial costs and a diversion of management’s attention and resources, which could harm our business.

If we fail to establish and maintain proper internal financial reporting controls, our ability to produce accurate financial statements or comply with applicable regulations could be impaired.

Pursuant to Section 404 of the Sarbanes-Oxley Act, we are required to file a report by our management on our internal control over financial reporting, including an attestation report on internal control over financial reporting issued by our independent registered public accounting firm. The presence of material weaknesses in internal control over financial reporting could result in financial statement errors which, in turn, could lead to errors in our financial reports and/or delays in our financial reporting, which could require us to restate our operating results. We might not identify one or more material weaknesses in our internal controls in connection with evaluating our compliance with Section 404 of the Sarbanes-Oxley Act. In order to maintain and improve the effectiveness of our disclosure controls and procedures and internal controls over financial reporting, we will need to expend significant resources and provide significant management oversight. Implementing any appropriate changes to our internal controls may require specific compliance training of our directors and employees, entail substantial costs in order to modify our existing accounting systems, take a significant period of time to complete and divert management’s attention from other business concerns. These changes may not, however, be effective in maintaining the adequacy of our internal control.

If we fail to maintain effective internal control over financial reporting in the future, our management and our independent registered public accounting firm may not be able to conclude that we have effective internal controls over financial reporting, investors may lose confidence in our operating results, the price of the ADSs could decline and we may be subject to litigation or regulatory enforcement actions. In addition, if we are unable to meet the requirements of Section 404 of the Sarbanes-Oxley Act, the ADSs may not be able to remain listed on the Nasdaq Global Market.

As a foreign private issuer, we are not subject to certain U.S. securities law disclosure requirements that apply to a domestic U.S. issuer, which may limit the information publicly available to our shareholders.

As a foreign private issuer we are not required to comply with all of the periodic disclosure and current reporting requirements of the Exchange Act and therefore there may be less publicly available information about us than if we were a U.S. domestic issuer. For example, we are not subject to the proxy rules in the United States and disclosure with respect to our annual general meetings will be governed by the Cayman Islands requirements. In addition, our officers, directors and principal shareholders are exempt from the reporting and “short-swing” profit recovery provisions of Section 16 of the Exchange Act and the rules thereunder. Therefore, our shareholders may not know on a timely basis when our officers, directors and principal shareholders purchase or sell our ordinary shares or ADSs.

As a foreign private issuer, we are permitted to adopt certain home country practices in relation to corporate governance matters that differ significantly from the Nasdaq Stock Market corporate governance listing standards. These practices may afford less protection to shareholders than they would enjoy if we complied fully with corporate governance listing standards.

As a foreign private issuer, we are permitted to take advantage of certain provisions in the Nasdaq Stock Market listing rules that allow us to follow Cayman Islands law for certain governance matters. Certain corporate governance practices in the Cayman Islands may differ significantly from corporate governance listing standards as, except for general fiduciary duties and duties of care, Cayman Islands law has no corporate governance regime which prescribes specific corporate governance standards. We follow Cayman Islands corporate governance practices in lieu of the corporate governance requirements of the Nasdaq Stock Market in respect of the following: (i) the majority independent director requirement under Section 5605(b)(1) of the Nasdaq Stock Market listing rules, (ii) the requirement under Section 5605(d) of the Nasdaq Stock Market listing rules that a compensation committee comprised solely of independent directors governed by a compensation committee charter oversee executive compensation, (iii) the requirement under Section 5605(e) of the Nasdaq Stock Market listing rules that director nominees be selected or recommended for selection by either a majority of the independent directors or a nominations committee comprised solely of independent directors and (iv) the requirement under Section 5605(b)(2) of the Nasdaq Stock Market listing

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rules that our independent directors hold regularly scheduled executive sessions. Cayman Islands law does not impose a requirement that our board of directors consist of a majority of independent directors. Nor does Cayman Islands law impose specific requirements on the establishment of a compensation committee or nominating committee or nominating process. Therefore, our shareholders may be afforded less protection than they otherwise would have under corporate governance listing standards applicable to U.S. domestic issuers.

We expect to lose our foreign private issuer status and be subject to U.S. domestic issuer disclosure requirements beginning in fiscal year 2021, which could result in significant additional costs and expenses.

As discussed above, we are currently a foreign private issuer, and therefore, we are not required to comply with all of the periodic disclosure and current reporting requirements of the Exchange Act. The determination of foreign private issuer status is made annually on the last business day of an issuer’s most recently completed second fiscal quarter and, accordingly, the next determination will be made with respect to us on June 30, 2020. Currently, more than 50% of our ordinary shares are directly or indirectly held by residents of the U.S. and, therefore, we expect that we will lose our foreign private issuer status as of June 30, 2020. If we lose our foreign private issuer status on this date, we will be required to file with the SEC periodic reports and registration statements on U.S. domestic issuer forms beginning on January 1, 2021, which are more detailed and extensive than the forms available to a foreign private issuer. We will also have to mandatorily comply with U.S. federal proxy requirements, and our officers, directors and principal shareholders will become subject to the short-swing profit disclosure and recovery provisions of Section 16 of the Exchange Act. In addition, we will lose our ability to rely upon exemptions from certain corporate governance requirements under the Nasdaq Stock Market listing rules. As a U.S. listed public company that is not a foreign private issuer, we will incur significant additional legal, accounting and other expenses that we will not incur as a foreign private issuer, and accounting, reporting and other expenses in order to maintain a listing on a U.S. securities exchange.

The audit report included in this Annual Report on Form 20-F was prepared by an auditor who is not inspected by the U.S. Public Company Accounting Oversight Board, or the PCAOB, and as such, you are deprived of the benefits of such inspection.

Auditors of companies that are registered with the SEC and traded publicly in the United States, including the independent registered public accounting firm of our company, must be registered with the PCAOB, and are required by the laws of the United States to undergo regular inspections by the PCAOB to assess their compliance with the laws of the United States and professional standards. Because substantially all of our operations are within China, a jurisdiction where the PCAOB is currently unable to conduct inspections without the approval of the Chinese authorities, our auditor is not currently inspected by the PCAOB.

In May 2013, the PCAOB entered into a Memorandum of Understanding on Enforcement Cooperation with the China Securities Regulatory Commission, or CSRC, and the Ministry of Finance, to establish a cooperative framework between the parties for the production and exchange of audit documents relevant to investigations undertaken by the PCAOB in the United States or the CSRC or the Ministry of Finance in the PRC. The PCAOB has announced that, since May 2013, cooperation has not been sufficient to enable the PCAOB to obtain timely access to relevant documents and testimony necessary to carry out its mission. The PCAOB continues to address these issues with Chinese regulators, and whether the PCOAB will obtain equivalent access remains an open issue.

This lack of PCAOB inspections in China prevents the PCAOB from evaluating audits and quality control procedures of any auditors operating in China, including our auditor. As a result, investors may be deprived of the benefits of PCAOB inspections. The inability of the PCAOB to conduct inspections of auditors in China makes it more difficult to evaluate the effectiveness of our auditor’s audit procedures or quality control procedures as compared to auditors outside of China that are subject to PCAOB inspections. Additionally, the SEC, the U.S. Department of Justice and other authorities often have substantial difficulties in bringing and enforcing actions against non-U.S. persons and companies, including those based in China. Investors should understand the attendant risks. Further, as a result, investors may lose confidence in our reported financial information and procedures and the quality of our financial statements as a result thereof.

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We do not currently intend to pay dividends on our securities, and, consequently, your ability to achieve a return on your investment will depend on appreciation in the price of the ADSs.

We have never declared or paid any dividends on our ordinary shares. We currently intend to invest our future earnings, if any, to fund our growth. Therefore, investors are not likely to receive any dividends on their ADSs at least in the near term, and the success of an investment in ADSs will depend upon any future appreciation in its value. Consequently, investors may need to sell all or part of their holdings of ADSs after price appreciation, which may never occur, to realize any future gains on their investment. There is no guarantee that the ADSs will appreciate in value or even maintain the price at which our investors purchased their ADSs.

The market price for our ADSs may be volatile which could result in substantial loss to you.

The market price for our ADSs has been volatile. From September 19, 2017 to April 24, 2020, the closing price of our ADSs ranged from a high of $65.80 to a low of $14.95 per ADS.

The market price of our ADSs is likely to be highly volatile and subject to wide fluctuations in response to factors, including the following:

In addition, the securities markets have from time to time experienced significant price and volume fluctuations that are not related to the operating performance of particular companies. For example, since August 2008, multiple exchanges in the United States and other countries and regions, including China, experienced sharp declines in response to the growing credit market crisis and the recession in the United States. As recently as March 2020, the exchanges in both the United States and China experienced a sharp decline. Prolonged global capital markets volatility may affect overall investor sentiment towards our ADSs, which would also negatively affect the trading prices for our ADSs.

Fluctuations in the value of the renminbi may have a material adverse effect on our results of operations and the value of your investment.

The value of the renminbi against the U.S. dollar and other currencies may fluctuate and is affected by, among other things, changes in political and economic conditions. On July 21, 2005, China government changed its decade-old policy of pegging the value of the renminbi to the U.S. dollar, and the renminbi appreciated more than 20% against the U.S. dollar over the following three years. Between July 2008 and June 2010, this appreciation halted, and the exchange rate between the renminbi and U.S. dollar remained within a narrow band. In June 2010, the PBOC announced that China government would increase the flexibility of the exchange rate, and thereafter allowed the renminbi to appreciate slowly against the U.S. dollar within the narrow band fixed by the PBOC. However, more recently, on August 11, 12 and 13, 2015, the PBOC significantly devalued the renminbi by fixing its price against the U.S. dollar 1.9%, 1.6%, and 1.1% lower than the previous day’s value, respectively. On October 1, 2016, the renminbi joined the International Monetary Fund’s basket of currencies that make up the Special Drawing Right, or SDR, along with the U.S. dollar, the Euro, the Japanese yen and the British pound. In the fourth quarter of 2016, the renminbi depreciated significantly while the U.S. dollar surged and China experienced persistent capital outflows. With the development of the foreign exchange

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market and progress towards interest rate liberalization and renminbi internationalization, the Chinese government may in the future announce further changes to the exchange rate system. There is no guarantee that the renminbi will not appreciate or depreciate significantly in value against the U.S. dollar in the future. It is difficult to predict how market forces or PRC or U.S. government policy may impact the exchange rate between the renminbi and the U.S. dollar in the future.

Significant revaluation of the renminbi may have a material adverse effect on your investment. For example, to the extent that we need to convert U.S. dollars into renminbi for our operations, appreciation of the renminbi against the U.S. dollar would have an adverse effect on the renminbi amount we would receive from the conversion. Conversely, if we decide to convert our renminbi into U.S. dollars for the purpose of making payments for dividends on our ordinary shares or ADSs or for other business purposes, appreciation of the U.S. dollar against the renminbi would have a negative effect on the U.S. dollar amount available to us. In addition, appreciation or depreciation in the value of the renminbi relative to U.S. dollars would affect our financial results reported in U.S. dollar terms regardless of any underlying change in our business or results of operations.

Very limited hedging options are available in China to reduce our exposure to exchange rate fluctuations. To date, we have not entered into any hedging transactions in an effort to reduce our exposure to foreign currency exchange risk. While we may decide to enter into hedging transactions in the future, the availability and effectiveness of these hedges may be limited and we may not be able to adequately hedge our exposure or at all. In addition, our currency exchange losses may be magnified by PRC exchange control regulations that restrict our ability to convert renminbi into foreign currency.

Holders of ADSs have fewer rights than shareholders and must act through the depositary to exercise their rights.

Holders of our ADSs do not have the same rights as our shareholders and may only exercise the voting rights with respect to the underlying ordinary shares in accordance with the provisions of the deposit agreement. Under our fourth amended and restated memorandum and articles of association, an annual general meeting and any extraordinary general meeting may be called with not less than seven days’ notice. When a general meeting is convened, you may not receive sufficient notice of a shareholders’ meeting to permit you to withdraw the ordinary shares underlying your ADSs to allow you to vote with respect to any specific matter. If we ask for your instructions, we will give the depositary notice of any such meeting and details concerning the matters to be voted upon at least 30 days in advance of the meeting date and the depositary will send a notice to you about the upcoming vote and will arrange to deliver our voting materials to you. The depositary and its agents, however, may not be able to send voting instructions to you or carry out your voting instructions in a timely manner. We will make all commercially reasonable efforts to cause the depositary to extend voting rights to you in a timely manner, but we cannot assure you that you will receive the voting materials in time to ensure that you can instruct the depositary to vote the ordinary shares underlying your ADSs. Furthermore, the depositary will not be liable for any failure to carry out any instructions to vote, for the manner in which any vote is cast or for the effect of any such vote. As a holder or beneficial owner of ADSs, you may have limited recourse if we or the depositary fail to meet our respective obligations under the deposit agreement or if you wish us or the depositary to participate in legal proceedings. As a result, you may not be able to exercise your right to vote and you may lack recourse if your ADSs are not voted as you request. In addition, in your capacity as an ADS holder, you will not be able to call a shareholders’ meeting.

You may not receive distributions on our ADSs or any value for them if such distribution is illegal or impractical or if any required government approval cannot be obtained in order to make such distribution available to you.

Although we do not have any present plan to pay any dividends, the depositary of our ADSs has agreed to pay to you the cash dividends or other distributions it or the custodian receives on ordinary shares or other deposited securities underlying our ADSs, after deducting its fees and expenses and any applicable taxes and governmental charges. You will receive these distributions in proportion to the number of ordinary shares your ADSs represent. However, the depositary is not responsible if it decides that it is unlawful or impractical to make a distribution available to any holders of ADSs. For example, it would be unlawful to make a distribution to a holder of ADSs if it consists of securities whose offering would require registration under the Securities Act but are not so properly registered or distributed under an applicable exemption from registration. The depositary may also determine that it is not reasonably practicable to distribute certain property. In these cases, the depositary may determine not to distribute such property. We have no obligation to register under the U.S. securities laws any offering of ADSs, ordinary shares, rights or other securities received through such distributions. We also have no obligation to take any other action to permit the distribution of ADSs, ordinary shares, rights or anything else to holders of ADSs. This means that you may not receive distributions we make on our ordinary shares or any value for them if it is illegal or impractical for us to make them available to you. These restrictions may cause a material decline in the value of our ADSs.

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Your right to participate in any future rights offerings may be limited, which may cause dilution to your holdings.

We may from time to time distribute rights to our shareholders, including rights to acquire our securities. However, we cannot make rights available to you in the United States unless we register the rights and the securities to which the rights relate under the Securities Act or an exemption from the registration requirements is available. Also, under the deposit agreement, the depositary bank will not make rights available to you unless either both the rights and any related securities are registered under the Securities Act, or the distribution of them to ADS holders is exempted from registration under the Securities Act. We are under no obligation to file a registration statement with respect to any such rights or securities or to endeavor to cause such a registration statement to be declared effective. Moreover, we may not be able to establish an exemption from registration under the Securities Act. If the depositary does not distribute the rights, it may, under the deposit agreement, either sell them, if possible, or allow them to lapse. Accordingly, you may be unable to participate in our rights offerings and may experience dilution in your holdings.

Taxing authorities could reallocate our taxable income among our subsidiaries, which could increase our overall tax liability.

We are incorporated under the laws of the Cayman Islands and currently have subsidiaries in China, Hong Kong, the Cayman Islands, the United States, Australia and the British Virgin Islands. If we succeed in growing our business we expect to conduct increased operations through our subsidiaries in various tax jurisdictions pursuant to transfer pricing arrangements between us, our parent company and our subsidiaries. If two or more affiliated companies are located in different countries, the tax laws or regulations of each country generally will require that transfer prices be the same as those between unrelated companies dealing at arms’ length and that appropriate documentation is maintained to support the transfer prices. While we believe that we operate in compliance with applicable transfer pricing laws and intend to continue to do so, our transfer pricing procedures are not binding on applicable tax authorities.

If tax authorities in any of these countries were to successfully challenge our transfer prices as not reflecting arms’ length transactions they could require us to adjust our transfer prices and thereby reallocate our income to reflect these revised transfer prices, which could result in a higher tax liability to us. In addition, if the country from which the income is reallocated does not agree with the reallocation, both countries could tax the same income, resulting in double taxation. If tax authorities were to allocate income to a higher tax jurisdiction, subject our income to double taxation or assess interest and penalties, it would increase our consolidated tax liability, which could adversely affect our financial condition, results of operations and cash flows.

A tax authority could asset that we are subject to tax in a jurisdiction where we believe we have not established a taxable connection, often referred to as a “permanent establishment” under international tax treaties, and such an assertion, if successful, could increase our expected tax liability in one or more jurisdictions. A tax authority may take the position that material income tax liabilities, interest and penalties are payable by us, in which case, we expect that we might contest such assessment. Contesting such an assessment may be lengthy and costly and if we were unsuccessful in disputing the assessment, the implications could increase our anticipated effective tax rate, where applicable.

If we are classified as a passive foreign investment company, U.S. investors could be subject to adverse U.S. federal income tax consequences.

Generally, if, for any taxable year, at least 75% of our gross income is passive income, or at least 50% of the value of our assets is attributable to assets that produce passive income or are held for the production of passive income, including cash, we would be characterized as a “passive foreign investment company,” or PFIC, for U.S. federal income tax purposes. For purposes of these tests, passive income generally includes dividends, interest, and gains from the sale or exchange of investment property and rents and royalties other than rents and royalties which are received from unrelated parties in connection with the active conduct of a trade or business. If we are a PFIC, U.S. holders of our ADSs may suffer adverse tax consequences, including having gains realized on the sale of the ADSs treated as ordinary income rather than capital gain, the loss of the preferential rate applicable to dividends received on the ADSs by individuals who are U.S. holders, and having interest charges apply to distributions by us and the proceeds of sales of the ADSs.

As discussed in “Material United States Federal Income Tax Considerations—Passive Foreign Investment Company Considerations,” we believe that our Hong Kong subsidiary, Zai Lab (Hong Kong) Limited, was a PFIC for its taxable year ended July 12, 2017 and that the Company and its other subsidiaries were not PFICs for the taxable years ended December 31, 2018 and 2019, and we do not expect that the Company and its subsidiaries will be treated as PFICs for the current taxable year, although no assurance can be provided in that regard. Notwithstanding the foregoing, the

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determination of whether we are a PFIC for any taxable year is a factual determination that can be made only after the end of each taxable year and which depends on the composition of our income and the composition and value of our assets for the relevant taxable year. Because we hold a substantial amount of passive assets, including cash, and because the value of our assets for purposes of the PFIC rules (including goodwill) may be determined by reference to the market value of our ADSs, which may be especially volatile due to the early stage of our products and drug candidates, and by how, and how quickly, we spend any cash that is raised in any financing transaction, we cannot give any assurance that we will not be a PFIC for the current or any future taxable year.

Whether or not U.S. holders make a timely “qualified electing fund,” or QEF election or mark-to-market election may affect the U.S. federal income tax consequences to U.S. holders with respect to the acquisition, ownership and disposition of our ADSs. Prospective investors should consult their own tax advisors regarding all aspects of the application of the PFIC rules to the ADSs. See “Material United States Federal Income Tax Considerations—Passive Foreign Investment Company Considerations.”

If a United States person is treated as owning at least 10% of our common shares, such holder may be subject to adverse U.S. federal income tax consequences.

If a U.S. Holder (as defined below under “Material United States Federal Income Tax Considerations”) is treated as owning (directly, indirectly or constructively) at least 10% of the value or voting power of our ADSs, such U.S. Holder may be treated as a “United States shareholder” with respect to each “controlled foreign corporation” in our group (if any). Because our group includes at least one U.S. subsidiary (Zai Lab (US), LLC), certain of our non-U.S. subsidiaries will be treated as controlled foreign corporations (regardless of whether Zai Lab Limited is treated as a controlled foreign corporation). A United States shareholder of a controlled foreign corporation may be required to annually report and include in its U.S. taxable income its pro rata share of “Subpart F income,” “global intangible low-taxed income” and investments in U.S. property by controlled foreign corporations, regardless of whether we make any distributions. An individual that is a United States shareholder with respect to a controlled foreign corporation generally would not be allowed certain tax deductions or foreign tax credits that would be allowed to a United States shareholder that is a U.S. corporation. We cannot provide any assurances that we will assist investors in determining whether any of our non-U.S. subsidiaries, if any, are treated as a controlled foreign corporation or whether such investor is treated as a United States shareholder with respect to any of such controlled foreign corporations. Further, we cannot provide any assurances that we will furnish to any United States shareholders information that may be necessary to comply with the reporting and tax paying obligations discussed above. Failure to comply with these reporting obligations may subject you to significant monetary penalties and may prevent the statute of limitations with respect to your U.S. federal income tax return for the year for which reporting was due from starting. U.S. holders should consult their tax advisors regarding the potential application of these rules to their investment in our ADSs.

Changes in tax law may adversely affect our business and financial results.

Under current law, we expect to be treated as a non-U.S. corporation for U.S. federal income tax purposes. The tax laws applicable to our business activities, however, are subject to change and uncertain interpretation. Our tax position could be adversely impacted by changes in tax rates, tax laws, tax practice, tax treaties or tax regulations or changes in the interpretation thereof by the tax authorities in jurisdictions in which we do business. Our actual tax rate may vary from our expectation and that variance may be material. A number of factors may increase our future effective tax rates, including: (1) the jurisdictions in which profits are determined to be earned and taxed; (2) the resolution of issues arising from any future tax audits with various tax authorities; (3) changes in the valuation of our deferred tax assets and liabilities; (4) our ability to use net operating loss carryforwards to offset future taxable income and any adjustments to the amount of the net operating loss carryforwards we can utilize, and (5) changes in tax laws or the interpretation of such tax laws, and changes in U.S. GAAP.

On December 22, 2017, President Trump signed into law new legislation that significantly revises the Internal Revenue Code of 1986, as amended. The newly enacted U.S. federal income tax law, among other things, contains significant changes to corporate taxation, including reduction of the corporate tax rate from a top marginal rate of 35% to a flat rate of 21%, limitation of the tax deduction for interest expense to 30% of adjusted earnings (except for certain small businesses), limitation of the deduction for net operating losses to 80% of current year taxable income and elimination of net operating loss carrybacks, one time taxation of offshore earnings at reduced rates regardless of whether they are repatriated, elimination of U.S. tax on foreign earnings (subject to certain important exceptions), immediate deductions for certain new investments instead of deductions for depreciation expense over time, and modifying or repealing many business deductions and credits. The overall impact of the new federal tax law is uncertain and our business and financial condition could be adversely affected. The impact of this tax reform on holders of our

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ADSs is also uncertain and could be adverse. We urge holders of our ADS to consult with their legal and tax advisors with respect to this legislation and the potential tax consequences of investing in or holding our ADSs.

You may have difficulty enforcing judgments obtained against us.

We are a company incorporated under the laws of the Cayman Islands, and substantially all of our assets are located outside the United States. Substantially all of our current operations are conducted in the PRC. In addition, some of our directors and officers are nationals and residents of countries other than the United States. A substantial portion of the assets of these persons are located outside the United States. As a result, it may be difficult for investors to effect service of process within the United States upon these persons. It may also be difficult for investors to enforce in U.S. courts judgments obtained in U.S. courts based on the civil liability provisions of the U.S. federal securities laws against us and our officers and directors, some of whom currently reside in the United States and whose assets are located outside the United States. In addition, there is uncertainty as to whether the courts of the Cayman Islands or China would recognize or enforce judgments of U.S. courts against us or such persons predicated upon the civil liability provisions of the securities laws of the United States or any state.

The recognition and enforcement of foreign judgments are provided for under China Civil Procedures Law. PRC courts may recognize and enforce foreign judgments in accordance with the requirements of China Civil Procedures Law based either on treaties between China and the country where the judgment is made or on principles of reciprocity between jurisdictions. China does not have any treaties or other forms of reciprocity with the United States that provide for the reciprocal recognition and enforcement of foreign judgments. In addition, according to China Civil Procedures Law, China courts will not enforce a foreign judgment against us or our directors and officers if they decide that the judgment violates the basic principles of PRC laws or national sovereignty, security or public interest. As a result, it is uncertain whether and on what basis a PRC court would enforce a judgment rendered by a court in the United States.

Investors may be subject to limitations on transfers of your ADSs.

ADSs are transferable on the books of the depositary. However, the depositary may close its transfer books at any time or from time to time when it deems expedient in connection with the performance of its duties. In addition, the depositary may refuse to deliver, transfer or register transfers of ADSs generally when our books or the books of the depositary are closed, or at any time if we or the depositary deems it advisable to do so because of any requirement of law or of any government or governmental body, or under any provision of the deposit agreement, or for any other reason.

ITEM 4.  INFORMATION ON THE COMPANY

A. History and Development of the Company

Our company was founded in the Cayman Islands on March 28, 2013 as an exempted company with limited liability under the Companies Law, Cap 22 (Law 3 of 1961, as consolidated and revised) of the Cayman Islands. Our principal executive offices are located at 4560 Jinke Road, Bldg. 1, 4F, Pudong, Shanghai, China 201210. Our telephone number at that address is +86 21 6163 2588. The address of our registered office in the Cayman Islands is Harbour Place 2nd Floor, 103 South Church Street, P.O. Box 472, George Town, Grand Cayman KY1-1106, Cayman Islands. Our agent for service of process in the United States is Cogency Global Inc., located at 10 E. 40th Street, 10th Floor, New York, NY 10016.

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The chart below shows our principal subsidiaries as of March 31, 2020.

Since our founding, we have raised approximately $164.6 million in private equity financing. In September 2017, we completed our initial public offering in the United States, listing on the Nasdaq Global Market, raising approximately $157.7 million in net proceeds after deducting underwriting commissions and the offering expenses payable by us. In September 2018, we completed a registered offering of ADSs, raising approximately $140.3 million in net proceeds after deducting underwriting commissions and the offering expenses payable by us. In May 2019, we completed a registered offering of ADSs, raising approximately $215.4 million in net proceeds after deducting underwriting commissions and the offering expenses payable by us. In January 2020, we completed a registered offering of ADSs, raising approximately $280.6 million in net proceeds after deducting underwriting commissions and the offering expenses payable by us. In addition, we have received government grants totaling approximately $8.7 million since our inception.

As of December 31, 2019, we had ten active in-licensed clinical drug candidates for development in China, Hong Kong, Macau and, in certain instances, Taiwan, Australia, New Zealand and other countries throughout the Asia Pacific region, through partnerships with GSK, BMS, Paratek, Five Prime, Entasis, Novocure, MacroGenics, Deciphera and Incyte. In April 2020, our portfolio was expanded to eleven clinical-stage drug assets with the addition of REGN1979, through our partnership with Regeneron. To date, we have made upfront, milestone and clinical cost reimbursement payments totaling approximately $167.9 million since our inception in connection with these licensing arrangements. In early 2017, we built a small molecule drug product facility in Suzhou, China capable of supporting clinical and commercial production. In 2018, we built a large molecule facility in Suzhou, China using GE Healthcare FlexFactory platform technology capable of supporting clinical production of our drug candidates. The cost to complete the small molecule facility was approximately $6.7 million and was paid with cash on hand. The construction of the large molecule facility was completed in 2018, which cost approximately $12.9 million to complete.

Business

Overview of Our Business

We are an innovative, research-based, commercial-stage biopharmaceutical company focusing on discovering or licensing, developing and commercializing proprietary therapeutics that address areas of large unmet medical need in the China and global markets, including in the fields of oncology, infectious and autoimmune diseases. As part of that effort, we have assembled a leadership team with global experience and an extensive track record in navigating the regulatory process to develop and commercialize innovative drugs. Our mission is to leverage our expertise and insight to address the expanding needs of patients in China and to utilize our China-based competencies to improve the lives of patients worldwide.

Furthermore, Zai Lab was built on the vision that, despite having a significant addressable market and sizable growth potential, China has historically lacked access to many innovative therapies available in other parts of the world and its drug development infrastructure has been underutilized. There remains the need to bring new and transformative therapies to China. In recent years, the Chinese government has focused on promoting local innovation through

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streamlining regulatory processes, improving drug quality standards and fostering a favorable environment, which we believe creates an attractive opportunity for the growth of innovation-focused companies such as Zai Lab.

As of April 2020, our portfolio consists of eleven assets, including two approved, commercial drug products and seven late-stage clinical assets targeting large, fast growing segments of China’s pharmaceutical market. ZEJULA, our lead drug candidate is an oral, once-daily small molecule PARP 1/2 inhibitor being developed and commercialized outside of China, Hong Kong and Macau by our partner, GSK. ZEJULA has the potential to be a differentiated drug for treatment across multiple solid tumor types in China, including ovarian and certain other types of cancer. In March 2017, ZEJULA received FDA marketing approval and in November 2017, it received EMA marketing approval as a maintenance treatment for recurrent platinum-sensitive epithelial ovarian cancer. In April 2017, Tesaro, Inc., or Tesaro, which was later acquired by GSK, commercially launched the product in the United States under the commercial name ZEJULA. In October 2018, the Hong Kong Department of Health approved our application for ZEJULA in Hong Kong for adult patients with platinum-sensitive relapsed high grade serous epithelial ovarian cancer who are in a complete response or partial response to platinum-based chemotherapy and we began commercializing ZEJULA in Hong Kong in the fourth quarter of 2018. In June 2019, we received marketing authorization to commercialize ZEJULA in Macau for women with relapsed ovarian cancer. In December 2019, ZEJULA was approved by the NMPA in China as a Category 1 maintenance therapy for adult patients with recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer, who are in a complete or partial response to platinum-based chemotherapy . ZEJULA was also designated as a “National Sciences and Technology Major Project” by the Chinese government as part of a key initiative to strengthen local innovation. In addition, the NMPA accepted and granted priority review to our supplemental New Drug Application, or sNDA, for ZEJULA as a maintenance treatment of adult patients with advanced epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in a complete or partial response to first-line platinum-based chemotherapy in March 2020 and April 2020, respectively. We are also exploring the combination potential of ZEJULA with immuno-oncology therapy, targeted therapy and chemotherapy in the clinically relevant indications.

Across our broader portfolio, we currently have over 25 ongoing or planned clinical trials. We believe that our leadership team’s extensive global drug development expertise, combined with our demonstrated understanding of the pharmaceutical industry, clinical resources and regulatory system in China, has provided us, and will continue to provide us, with opportunities to bring innovative products to market in China efficiently.

Our current eleven clinical-stage drug candidates were in-licensed for development in China, Hong Kong, Macau and, in certain instances, Taiwan, Australia, New Zealand and other countries throughout the Asia Pacific region.

We have built a premier, fully integrated drug discovery and development platform that aims to bring both in-licensed and internally-discovered medicines to patients in China and globally. Our in-house research and development team had previously been directly involved in the discovery and development of several innovative drug candidates at Hutchison Medi-Pharma, including fruquintinib and savolitinib. Our in-house research and development team focuses on the development of innovative therapeutics for the treatment of oncology and auto-immune diseases. We believe our discovery efforts will enable us to achieve our long-term goal of generating a sustainable, internally discovered product pipeline of new products and drug candidates for patients around the world. This effort has resulted in the identification of a number of proprietary candidates against targets in our focus areas that include immuno-oncology, DNA damage response/repair and oncogenic signaling that we are moving into pre-clinical development. Our company has a leadership team with extensive pharmaceutical research, development and commercialization track records in both global and Chinese biopharmaceutical companies. We believe this team and our in-house discovery and development capabilities will enable us to achieve our long-term goal of commercializing our internally discovered innovative medicine for patients worldwide.

We have built our own commercial team consisting of more than 298 employees as of December 31, 2019 to launch our portfolio of drug products. Part of our strategy to become a fully integrated biopharmaceutical company is the ability to produce both large and small molecule therapeutics under global standards, such as current good manufacturing practices, or cGMP. To this end, in the first half of 2017, we built a small molecule drug product facility capable of supporting clinical and commercial production, and in 2018, we built a large molecule facility capable of supporting clinical production of our drug candidates.

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Our Innovative Pipeline

We have a broad pipeline of proprietary products and drug candidates that range from discovery stage to late-stage clinical to commercial-stage programs. The following table summarizes our commercial products, clinical-stage drug candidates and programs.

Our Products and Late-Stage Clinical Pipeline

As of December 31, 2019, our pipeline included two commercial products in China, Hong Kong and Macau and eight clinical-stage assets in oncology and infectious diseases, two therapeutic areas where there is a large unmet need and lack of innovative treatment options in China. In April 2020, our portfolio was further expanded with the addition of REGN1979. Within our broad and validated portfolio, the approved products and late-stage clinical drug candidates are:

Our Products

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Late-Stage Clinical Pipeline

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For our late-stage oncology drug candidates with China, Hong Kong, Macau and Taiwan rights, our near-term development plan focuses on specific patient segments. These segments have an estimated annual incidence of over 1.6 million patients in China. We expect that the commercial success of our products will be driven by their differentiated clinical profiles, efficacy in Chinese patients and ability to provide clinical benefits over existing standards of care in a market where targeted therapies are either unavailable or less utilized relative to more developed markets.

Within our anti-infective portfolio, we believe that our two novel antibiotics, omadacycline and durlobactam, will address significant unmet patient and market needs.

With omadacycline, we have the chance to introduce into China a new broad-spectrum antibiotic with excellent activity not only against common Gram-positive and Gram-negative bacteria, but also against several MDR pathogens. The profile of omadacycline includes MRSA, penicillin- and macrolide-resistant streptococci, enterococci and ESBL-E. coli isolates. In addition, the availability of an IV and oral formulation allows step-down treatment of infections in the hospital and continued oral therapy in the ambulatory care setting. This favorable antimicrobial spectrum has been confirmed now for Chinese isolates as well.

With durlobactam, in collaboration with our partner, we are focusing on the combination with sulbactam, which we believe provides unique and specific bactericidal activity against Acinetobacter baumannii spp., an extremely difficult-to-treat pathogen associated with high mortality that is more prevalent in China than most other countries. In a study conducted by Zai Lab of Acinetobacter pathogens from Chinese patients, durlobactam demonstrated excellent activity against all isolates including MDR and carbapenem-resistant strains. The prevalent overuse of antibiotics, the evolution of resistant bacteria and state of current treatment practices are expected to lead to an increase in drug-resistant infection rates. In 2013, total antibiotic usage in China accounted for about half of the global antibiotic usage, with a per-capita use of antibiotics being more than five times that in Europe and the United States.

In 2015, the estimated incidence for ABSSSI and CABP was 2.8 million patients and 16.5 million patients, respectively, in China alone. In 2016, based on a national survey of over 1,300 hospitals in China, there were approximately 210,000 Acinetobacter baumannii infections. Due to the high rates of MDR, the Chinese government has identified the goal of developing one to two innovative anti-infective drugs by 2020.

In addition to mainland China, we intend to seek registration and commercialization of the above drug candidates in all areas where we have applicable rights. Notably in Hong Kong and Macau, products with existing approvals by the FDA, EMA or a comparable regulatory agency are eligible for an expedited registration process that does not require conducting local clinical trials.

While the overall patient population in Hong Kong and Macau is smaller compared to that of China, they are higher income markets with developed medical infrastructure, widely available private insurance and proven capacity to pay for advanced therapeutics. In addition to local patients, there is a significant opportunity to provide treatment for medical tourists from China, who visit these regions in order to access high-end cancer treatment, including prescription drugs that may not be available in mainland China.

Our Discovery Pipeline

Our in-house discovery team is dedicated to the research and discovery of novel therapeutics in the areas of oncology and autoimmune diseases, with a focus on large market opportunities with unmet clinical needs. Our aim is to produce up to two global INDs starting in 2020. We believe our discovery efforts will enable us to achieve our long-term goal of generating a sustainable, internally discovered product pipeline of new products and drug candidates for patients around the world. This effort has resulted in the identification of a number of proprietary candidates against targets in our focus areas that include immuno-oncology, DNA damage response/repair and oncogenic signaling that we are moving into pre-clinical development. Our discovery operations in Shanghai, China was established in 2016. Our discovery operations in San Francisco, California, was established in 2018. Our U.S. discovery team focuses on generating small and large molecule therapeutics and is currently creating a proprietary, best-in-class human Ig transgenic mouse platform.

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Our Clinical Pipeline

ZEJULA

ZEJULA is a highly potent and selective oral, once-daily small molecule poly (ADP-ribose) polymerase 1/2, or PARP 1/2, inhibitor with the potential to be a first-in-class Category 1 drug for treatment across multiple solid tumor types in China. ZEJULA was approved in March 2017 by the FDA and in November 2017 by EMA, as a maintenance treatment for women with recurrent platinum-sensitive ovarian cancer. Maintenance therapy is for those women who have had prior treatment but are expected to see their cancer return, with the purpose of avoiding or slowing a recurrence if the cancer is in remission after the prior treatment. A platinum-sensitive cancer is one that responded to initial platinum-based chemotherapy and remained in remission post-chemotherapy for more than six months.

ZEJULA is the first PARP inhibitor to be approved by the FDA for ovarian cancer that does not require BRCA mutation or other biomarker testing. This makes ZEJULA suitable for a wide patient population and significantly more accessible to patients in China where BRCA biomarker diagnostic tests are not widely available.

We obtained an exclusive license for the development and commercialization of ZEJULA in China, Hong Kong and Macau in 2016. We commercialized ZEJULA in Hong Kong in the fourth quarter of 2018. In October 2018, the Hong Kong Department of Health approved our application for ZEJULA in Hong Kong for adult patients with platinum-sensitive relapsed high grade serous epithelial ovarian cancer who are in a complete response or partial response to platinum-based chemotherapy and we began commercializing ZEJULA in Hong Kong in the fourth quarter of 2018. In June 2019, we received marketing authorization to commercialize ZEJULA in Macau for women with relapsed ovarian cancer. In December 2019, ZEJULA was approved by the NMPA in China as a Category 1 maintenance therapy for adult patients with recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer, who are in a complete or partial response to platinum-based chemotherapy. ZEJULA was also designated as a “National Sciences and Technology Major Project” by the Chinese government as part of a key initiative to strengthen local innovation. In addition, the NMPA accepted and granted priority review to our sNDA for ZEJULA as a maintenance treatment of adult patients with advanced epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in a complete or partial response to first-line platinum-based chemotherapy in March 2020 and April 2020, respectively.

We initiated the Phase III study of ZEJULA in patients with recurrent platinum-sensitive ovarian cancer as a second-line maintenance therapy in September 2017. In May 2018, we completed enrollment ahead of schedule for our pharmacokinetics, or PK, study for Chinese patients with platinum-sensitive ovarian cancer, and in June 2018, we initiated the second Phase III study in patients with platinum-responsive ovarian cancer as a first-line maintenance therapy and dosed our first patient. These studies are similar in design to Tesaro’s clinical studies of niraparib in ovarian cancer. In August 2018, we completed our PK study for Chinese patients with platinum-sensitive ovarian cancer, which demonstrated a comparable efficacy profile to studies in non-Chinese patients. We continue to explore ZEJULA in patients with breast cancer and non-small cell lung cancer in China. In February 2020, Zai Lab dosed the first patient in the Phase Ib study of niraparib with MGD-013, a first-in-class PD1/LAG-3 bispecific antibody, in advanced or metastatic gastric cancer. We are also exploring the combination potential of ZEJULA with immuno-oncology therapy, targeted therapy and chemotherapy in the clinically relevant indications.

Ovarian Cancer

Ovarian cancer had an estimated annual incidence of 52,000 patients in China in 2015, which is more than double that of the 21,300 patients in the United States and has seen increasing mortality rates. Since early symptoms of ovarian cancer are non-specific and difficult to detect, a majority of women with ovarian cancer are diagnosed when the disease is at an advanced stage, when prognosis is poor. Finding effective therapeutic approaches for advanced ovarian cancer patients represents a large unmet medical need. Given the broad applicability of ZEJULA across all patient populations, regardless of gBRCA mutation status, we are currently targeting the entire platinum sensitive ovarian cancer patient population. This represents a significant advantage for patient convenience and access, given that there is no need for patients to utilize diagnostic tests to determine their gBRCA mutation status, particularly in China where such tests are not widely available.

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The current standard of care in China consists of radical surgery and platinum-based chemotherapy. Although platinum-based chemotherapy is effective at inducing an initial response, ovarian cancer will recur in approximately 85% of women. Many women continue to respond to second-line platinum based chemotherapy, and following a response, the guideline-recommended approach for many patients is surveillance, monitoring patients for disease progression and managing their symptoms. However, during the surveillance period, ovarian cancer survivors report anxiety about cancer antigen testing and fear of recurrence, many experiencing symptoms associated with post-traumatic stress disorder. After relapse, patients respond moderately or poorly to subsequent chemotherapy, with later lines of therapy leading to progressively shorter treatment-free intervals. Therefore, we believe effective maintenance therapies that address a broad patient population are needed to prolong the duration of response following platinum-based treatment.

Lung Cancer

Lung cancer has the highest total incidence as well as the highest mortality rate of any cancer in China. Annual incidence was estimated at 733,300 patients in China in 2015, which is more than triple the 221,200 patients in the United States for the same period. We intend to explore ZEJULA’s efficacy in patients with lung cancer based on the large unmet need for effective treatment for such patients in China. According to the American Cancer Society, approximately 80% to 85% of lung cancers are non-small cell lung cancer and squamous cell carcinoma is about 25% to 30% of lung cancers.

Our Clinical Trial Designs and Strategy for ZEJULA in the China Market

Ovarian Cancer

In September 2018, we completed our open-label study evaluating the pharmacokinetic, or PK, profile of ZEJULA made in China in Chinese ovarian cancer patients. Results from the study show comparable PK profile of the Chinese patients administered ZEJULA to that of patients evaluated in Tesaro’s global PK study. The study demonstrated that the drug exposure increased proportionally from 100mg to 300mg, with a Tmax of approximately three hours. Systemic exposure of ZEJULA, as measured by Cmax and AUC, increased approximately proportionally with increased dose. There were no unexpected safety issues noted during the trial. All key PK and safety parameters were comparable to those in global studies. The study results and population PK data did not identify ethnicity differences between Chinese and non-Chinese patients.

In January 2019, we completed patient enrollment of our Phase III trial evaluating ZEJULA as a second-line maintenance therapy in patients with recurrent platinum-sensitive ovarian cancer. Recurrent ovarian cancer patients who have responded to a platinum-containing regimen were enrolled in the study and randomized 2:1 to receive either ZEJULA or placebo once daily. Patients were stratified by gBRCA status. Patients will be randomly assigned in a 2:1 ratio to receive ZEJULA or placebo once daily. Patients will be stratified by gBRCA status. The primary endpoint is progression-free survival. The primary analysis will be conducted in the entire study population, regardless of gBRCA mutation status. If the primary analysis meets the statistical significance, the study will be ended. If it does not, the study will continue for gBRCA mutation positive patients with the second-step primary analysis conducted in this population.

In November 2019, we completed patient enrollment of our Phase III trial evaluating ZEJULA as a first-line maintenance therapy in patients who are in a complete or partial response to first-line platinum-based chemotherapy. Advanced ovarian cancer patients were randomized 2:1 to receive niraparib or placebo as maintenance therapy. Randomization was stratified by use of neoadjuvant chemotherapy (yes or no), best response to platinum therapy (CR or PR), and homologous recombination deficiency (HRD) status (positive or negative/not determined). The primary end point was progression-free survival (PFS) in patients who had tumors with HRD+ve and in those in the overall population, as determined on hierarchical testing.

In China, ZEJULA has been approved as a Category 1 drug by the NMPA in December 2019 as maintenance therapy for adult patients with recurrent epithelial ovarian, fallopian tube, or primary peritoneal cancer, who are in a complete or partial response to platinum-based chemotherapy. The NMPA accepted and granted priority review to our sNDA for ZEJULA as a maintenance treatment of adult patients with advanced epithelial ovarian, fallopian tube, or primary peritoneal cancer who are in a complete or partial response to first-line platinum-based chemotherapy in March 2020 and April 2020, respectively.

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Lung Cancer

We initiated a Phase III study in patients with platinum responsive small cell lung cancer as maintenance therapy in August 2018. Given the rapidly changing landscape in the management of small cell lung cancer, particularly with the introduction of PD1/PD-L1 antibodies in the first-line treatment of small cell lung cancer, we terminated this study to prioritize our resources to other opportunities including exploring potential combination regimen for ZEJULA and immuno-oncology agents in the maintenance setting for non-small cell lung cancer.

We continue to explore the combination potential of ZEJULA with immuno-oncology therapy, targeted therapy and chemotherapy in the other clinically relevant indications.

Background on PARP Inhibitors

One well-studied area of PARP activity relates to DNA repair. DNA contains genetic instructions used in the development and functioning of most known living organisms. DNA can be damaged by many types of mutagens, including oxidizing agents, alkylating agents, ultraviolet light and X-rays. An important property of DNA is that it can replicate, or make copies of itself. This is critical when cells divide because each new cell needs to have an exact copy of the DNA present in the old cell. It is also critical to the integrity and survival of cells that DNA damage can be repaired. Cells have evolved multiple mechanisms to enable such DNA repair, and these mechanisms are complementary to each other, each driving repair of specific types of DNA damage. If a cell’s DNA damage repair system is overpowered, then the cell is programmed to die.

Radiation and certain chemotherapies such as alkylating agents and topoisomerase inhibitors induce significant damage to tumor cells, which results in programmed cell death. DNA repair mechanisms may reduce the activity of these anti-cancer therapies and, conversely, inhibition of DNA repair processes may enhance the effects of DNA-damaging anti-cancer therapy. For example, cancer cells can maintain viability despite disruption of the key DNA repair pathway known as the homologous recombination pathway, but they become particularly vulnerable to chemotherapy if an alternative DNA repair pathway is disrupted. This is known as “synthetic lethality”—a situation where the individual loss of either repair pathway is compatible with cell viability, but the simultaneous loss of both pathways results in cancer cell deaths. Since PARP inhibitors block DNA repair, PARP inhibition is thought to be an important part of cancer therapy.

Clinical studies have shown that PARP inhibitors are effective as a monotherapy in patients with certain types of cancer, including those with gene mutations as discussed below. PARP inhibitors have also been explored in numerous clinical trials to enhance chemotherapy treatments, including in combination with temozolomide (TMZ), cisplatin, carboplatin, gemcitabine and topotecan.

ZEJULA Mechanism of Action

Many DNA repair processes involve PARP-1 and PARP-2, which are zinc-finger DNA-binding enzymes that sense DNA damage and convert it into intracellular signals to promote DNA repair. PARP inhibitors block DNA repair by the base excision repair pathway. PARP inhibitors appear most effective when used to treat tumors with underlying defects in DNA repair or when combined with another DNA-damaging agent. This is because, in normal cells, the homologous recombination pathway compensates for PARP-mediated inhibition of the base excision repair pathway and maintains the fidelity of DNA repair. In cells with a deficiency in the homologous recombination pathway, such as those with BRCA-1 and BRCA-2 mutations, PARP inhibition leads to irreparable double-strand breaks, collapsed replication forks, and an increased use of the less effective nonhomologous end joining pathway. These disruptions ultimately result in synthetic lethality, and, in this manner, treatment with PARP inhibitors represents an opportunity to selectively kill cancer cells with deficiencies in homologous recombination and other DNA repair mechanisms. PARP inhibitors also have an additional mechanism of action known as “PARP trapping.” The effect of PARP trapping is to poison DNA by stabilizing PARP-1 and PARP-2 at sites of DNA damage, generating complexes that may be even more toxic than the unrepaired single-strand breaks which result from PARP inhibition.

ZEJULA is designed to be a highly potent, selective inhibitor of PARP-1 and PARP-2. In an ovarian cancer patient-derived xenograft model, where tumor models are established from transplantation of a human tumor specimen from a cancer patient directly into a mouse, ZEJULA has been shown to have greater tumor concentration, allowing it to deliver sustained anti-tumor activity as compared to olaparib, an FDA-approved PARP inhibitor marketed by AstraZenaca for gBRCA+ ovarian cancer patients who have received at least three prior lines of chemotherapy.

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ZEJULA Clinical Results

NOVA, a Phase III maintenance study of ZEJULA versus placebo in patients with recurrent platinum-sensitive ovarian cancer.

In March 2017, the FDA approved ZEJULA as a maintenance treatment for women with recurrent platinum-sensitive ovarian cancer, regardless of BRCA mutation or biomarker status, three months ahead of the FDA’s scheduled decision date (PDUFA date). ZEJULA’s FDA approval followed the release of successful results from Tesaro’s NOVA trial in which ZEJULA demonstrated a clinically meaningful increase in progression-free survival in women with recurrent ovarian cancer, regardless of gBRCA mutation or biomarker status. Treatment with ZEJULA reduced the risk of disease progression or death by 73% in gBRCA mutation positive patients (hazard ratio = 0.27) and by 55% in patients without gBRCA mutations (hazard ratio = 0.45). Hazard ratio is the probability of an event (such as disease progression or death) occurring in the treatment arm divided by the probability of the event occurring in the control arm of a study, with a ratio of less than one indicating a lower probability of an event occurring for patients in the treatment arm. P-value is a measure of the probability of obtaining the observed sample results, with a lower value indicating a higher degree of statistical confidence in these studies. The magnitude of benefit was similar for patients entering the trial with a partial response or a complete response to platinum treatment.

The NOVA trial was a Phase III randomized double-blind trial that assessed the effectiveness of ZEJULA compared with placebo to delay tumor progression following a platinum containing chemotherapy regimen. Patients enrolled into one of two independent cohorts based on gBRCA mutation status. A total of 553 patients were enrolled in the NOVA study at 107 centers worldwide. The study population has 203 patients assigned to the gBRCA mutation positive cohort and 350 patients assigned to the gBRCA mutation negative cohort. Among the patients in the gBRCA mutation negative cohort, 162 had tumors that were tumors deficient in homologous recombination, or HRDpos, and 134 had tumors did not have a homologous recombination deficiency, or HRDneg. The homologous recombination deficiency status was not determined for 54 patients. The gBRCA mutation negative cohort analyses included all patients randomized, regardless of homologous recombination deficiency status.

Within each cohort, patients were randomized 2:1 to receive ZEJULA or placebo, and were continuously treated with placebo or ZEJULA until progression. The primary endpoint of this study was progression free survival. Secondary endpoints included patient-reported outcomes, chemotherapy free interval length, and OS. This trial successfully achieved its primary endpoint in both cohorts, showing that ZEJULA treatment significantly prolonged progression free survival, compared to control in patients who were gBRCA mutation positive and in patients who were gBRCA mutation negative. In addition, within the gBRCA mutation negative cohort, ZEJULA treatment significantly prolonged progression free survival compared to placebo for the prospectively defined patient population with HRDpos tumors. A high proportion of patients in both treatment groups in both cohorts had received three or four prior lines of chemotherapy. The most common treatment-emergent grade 3/4 adverse events in the ZEJULA arm of the NOVA study, based on the National Cancer Institute’s Common Terminology Criteria for Adverse Event, or CTC, which is a set of criteria for the standardized classification of adverse effects of drugs used in cancer therapy (with one and two being relatively mild and higher numbers up to five being more severe), were thrombocytopenia, anemia, and neutropenia.

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The figures below present the results for the primary endpoint of progression free survival for the three primary efficacy populations.

Figure 1: Progression free survival was significantly longer for patients who received ZEJULA compared to those who received placebo for all primary efficacy populations.

Source: Tesaro.

Notes: gBRCAmut = gBRCA mutation positive; non-gBRCA mut = gBRCA mutation negative

Figure 2: Progression free survival in the gBRCA mutation positive cohort of patients treated with ZEJULA versus placebo

Source: Tesaro.

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Figure 3: Progression free survival in the HRDpos group of the gBRCA mutation negative cohort of patients treated with ZEJULA versus placebo

Source: Tesaro.

Figure 4: Progression free survival in the overall gBRCA mutation negative cohort of patients treated with ZEJULA versus placebo

Source: Tesaro.

Within the gBRCA mutation positive cohort, the median progression free survival was 21.0 months on ZEJULA versus 5.5 months on placebo (hazard ratio=0.27; p

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As it is maintenance therapy, quality of life is important to patients receiving treatment. Patient-reported outcome data from validated survey tools indicated that ZEJULA-treated patients reported no significant difference from placebo in measures associated with symptom specific and general quality of life.

Furthermore, ZEJULA treatment did not reduce the effectiveness of subsequent therapies, and continued to show carry-over of the beneficial treatment effect in the secondary efficacy measure of second objective disease progression, which is time from randomization to objective tumor progression on next-line treatment or death from any cause. OS data, while immature, showed no negative impact of ZEJULA treatment.

The incidences of CTC grade 3/4 treatment-emergent adverse events (74% vs 23%), serious adverse events (30% vs 15%), treatment-emergent adverse events leading to treatment interruption (69% vs 5%), treatment-emergent adverse events leading to dose reduction (67% vs 15%), and treatment-emergent adverse events leading to treatment discontinuation (15% vs 2%) were higher for ZEJULA versus placebo. There were no on-treatment deaths reported.

The most commonly observed hematologic treatment-emergent adverse events (all CTC grades) related to ZEJULA were thrombocytopenia (61%), anemia (50%) and neutropenia (30%). Although CTC grade 3/4 hematologic laboratory events were common at the initiation of treatment, no severe clinical sequelae were observed and relatively few patients discontinued due to these adverse events. Dose adjustment based on individual tolerability during the first cycles substantially reduced the incidence of these events beyond the third 28-day treatment cycle, indicating the overall effectiveness of the approach to dose modification. Overall the treatment-emergent adverse events were manageable, with no negative impact on quality of life.

PRIMA, a Phase III maintenance study of ZEJULA versus placebo in patients with advanced ovarian cancer following response on front-line platinum-based chemotherapy.

PRIMA is a randomized, double-blind, phase III trial evaluating niraparib versus placebo as maintenance therapy in patients with advanced ovarian cancer following response on front-line platinum-based chemotherapy. The study was designed to enrol subjects with Stage III or IV ovarian cancer (including fallopian and peritoneal cancers) who had previously completed front-line platinum-based therapy with a physician-assessed response of CR or PR. Randomization was stratified by use of neoadjuvant chemotherapy (yes or no), best response to platinum therapy (CR or PR), and homologous recombination deficiency (HRD) status (positive or negative/not determined). The primary end point was progression-free survival (PFS) in patients who had tumors with HRD+ve and in those in the overall population, as determined on hierarchical testing.

From July 2016 through June 2018 and across 220 sites worldwide, a total of 733 patients were randomized at 2:1 to receive niraparib or placebo as maintenance therapy, of whom 373 (50.9%) had tumors with HRD. Among the patients in this category, the median PFS was significantly longer in the niraparib group than in the placebo group (21.9 months vs. 10.4 months; hazard ratio for disease progression or death, 0.43; 95% confidence interval [CI], 0.31 to 0.59; P

The safety profile observed in the PRIMA study was consistent with the known safety profile of niraparib seen in previous clinical studies and other PARP inhibitors, including gastrointestinal and hematological events. In the safety population, for the niraparib versus placebo treatment arms, the incidences of CTCAE Grade ≥3 TEAEs (70.5% versus 18.9%), SAEs (32.2% versus 13.1%), TEAEs leading to treatment interruption (79.5% versus 18.0%), TEAEs leading to dose reduction (70.9% versus 8.2%), and of TEAEs leading to treatment discontinuation (12.0% versus 2.5%) were higher for those receiving niraparib vs placebo. There were no on-treatment deaths reported during the study. The incidence of the most commonly reported events (overall and Grade ≥3) was higher for subjects who received a fixed starting dose of niraparib (300mg) compared with those who received an individualized starting dose based on baseline body weight and platelet count (300mg or 200mg).

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Table 1: Primary efficacy endpoint of PFS based on blinded independent central review (BICR) (ITT Population)

Source: GSK.

Figure 5: Kaplan-Meier plot of PFS by BICR assessment in subjects with HRD tumors (ITT Population)

Source: GSK.

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Figure 6: Kaplan-Meier plot of PFS by BICR assessment in overall population (ITT Population)

Source: GSK.

Based on PRIMA results, sNDA application for niraparib for first-line maintenance treatment for women with platinum-responsive advanced ovarian cancer has been submitted to FDA.

ZEJULA Pre-clinical Development

As discussed below, Merck, Sharp & Dohme Corp. (a subsidiary of Merck & Co. Inc.), or Merck Corp., and our partner Tesaro (now GSK) have completed various pre-clinical trials to evaluate the pharmacodynamics, pharmacokinetics and toxicology profile of ZEJULA.

Pharmacodynamics . In pre-clinical trials studying ZEJULA’s pharmacodynamics, ZEJULA was found to be a potent and selective PARP-1 and PARP-2 inhibitor that displayed at least a 100-fold selectivity over other PARP-family members PARP-3, v-PARP, and Tankyrase-1. A commonly used quantitative measure of potency is IC ₉₀ , which represents the concentration of a drug that is required to suppress 90% of the target enzyme. The IC ₉₀ of ZEJULA for PARylation in BRCA-deficient tumor cells correlates with functional suppression of single strand breakage repair and anti-tumor effects on BRCA mutation positive tumor cells.

Normal primary cells were resistant to ZEJULA with the most sensitive cells (megakaryocytes) exhibiting a 13-fold selectivity margin as compared to BRCA mutation positive tumor cells in vitro . Maximal in-vivo efficacy was achieved in BRCA 1 mutation positive ovarian tumor models with once-daily oral administration of ZEJULA at a dose sufficient to suppress 90% of the PARP enzymatic activity in the tumor at eight hours after the dose, which translated to greater than 50% inhibition of PARP activity in peripheral blood mononuclear cells at eight hours post dose.

The therapeutic potential of ZEJULA was evaluated in a study designed to examine the benefit of ZEJULA in maintenance setting, i.e., daily ZEJULA treatment following a regression induced with a platinum-based regimen. In this study, tumors in mice receiving maintenance ZEJULA therapy became undetectable whereas regrowth was observed in those receiving only the chemotherapy regimen. These data support the concept that maintenance ZEJULA therapy after tumor response to chemotherapeutic agents may prolong recurrence-free survival.

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ZEJULA showed no significant observable effects in nonclinical safety pharmacology studies at clinically relevant doses across the species evaluated.

Pharmacokinetics. ZEJULA elicited desirable and consistent pharmacokinetic profiles in nonclinical species in vivo. The oral absorption in rats and dogs was rapid, with moderate to high bioavailability. The compound is readily distributed to the brains of rats and monkeys to a modest extent, suggesting additional therapeutic potential.

Elimination of ZEJULA and its metabolites was fecal and renal in rats, while mainly renal in dogs. The potential risk for drug—drug interactions was determined to be minimal for ZEJULA, due to the lack of the interactions between ZEJULA and the hepatic drug-metabolizing CYP enzymes, the major hepatic and renal uptake transporters (OATP1B1, OATP1B3, OAT1, OAT3, and OCT2), and BSEP, an efflux transporter known to be associated with hepatotoxicity. The in vitro metabolic results, combined with the in vivo pharmacokinetic findings, demonstrated that ZEJULA had a desirable disposition profile with a minimal potential for drug—drug interactions, consistent with the development of ZEJULA as an anticancer agent.

Toxicology . A comprehensive pre-clinical toxicology program was conducted to support the administration of ZEJULA in patients with cancer. This program included oral repeat-dose toxicity studies (up to three-months duration) in dogs and rats, genotoxicity and phototoxicity studies. The results obtained from the general toxicity studies in rats and dogs indicated that ZEJULA causes bone marrow suppression which leads to decreases in circulating white and red blood cells. Infections and septicemia were a consequence of bone marrow suppression and lymphoid depletion. These findings are linked to pharmacology of ZEJULA and showed reversibility.

ZEJULA—Pharmacokinetics

The pharmacokinetic profile of ZEJULA has been evaluated in multiple clinical studies, with an overall ZEJULA-dosed population of 526 patients.

Absorption . ZEJULA exhibited linear pharmacokinetic, dose proportional exposure, and dose-independent absorption and clearance. Following repeat administrations of the daily recommended dose of 300 mg, ZEJULA accumulation on day 21 was consistent for both the area under the plasma concentration-time curve and maximum concentration (approximately two- to three-fold). ZEJULA was shown to be highly orally bioavailable (F ~73%). Bioavailability is a measure of the absorption of drug and is expressed as a percentage of the administrated case of the drug which reaches the patient’s system. ZEJULA can be administered with or without food.

Distribution . ZEJULA was moderately protein bound to human plasma (83.0%). The apparent volume of distribution was 1220 L, indicating an extensive tissue distribution of ZEJULA.

Metabolism . The carboxylesterases-catalyzed amide hydrolysis was delineated to be the major primary pathway, followed by the uridine-5’-diphospho-glucuronosyltransferases (UGT)-mediated glucuronidation and the other minor secondary pathway ( i.e ., methylation). The major circulating metabolites in humans are the carboxylic acid and the glucuronides of carboxylic acid. The metabolic profile seen in humans is consistent with what was detected in the experimental species (rats and dogs).

Elimination . In an absorption, metabolism and elimination study in cancer patients using 14C-radioactive ZEJULA, a mean measured total of 86.2% of the radioactive dose was recovered in urine and fecal samples collected daily from 0 to 504 hours (21 days) post dose after single oral administration of 14C-ZEJULA. It suggests minimal long-term retention of ZEJULA or its metabolites in body. Moreover, hepatobiliary clearance and renal excretion are the major routes of elimination in humans.

Intrinsic Effects . Population pharmacokinetic analysis identified no intrinsic factors such as age, race, hepatic impairment, renal impairment would have significant impact on the pharmacokinetic of ZEJULA.

Optune and Tumor Treating Fields

Overview of Tumor Treating Fields

Tumor Treating Fields were invented in 2000 by Professor Emeritus Yoram Palti of the Technion Institute of Technology in Israel, who founded Novocure (Israel) in 2000, conducted pre-clinical studies of Tumor Treating Fields, developed a medical device capable of delivering Tumor Treating Fields to patients, and finally brought Tumor Treating

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Fields into clinical use through clinical testing in patients with recurrent glioblastoma. Today, after more than 15 years of pre-clinical research, it is known that Tumor Treating Fields are an electric field based loco-regional, antimitotic treatment modality, which inhibits the growth of cancerous tumors in vitro and in vivo . As intermediate frequency (200 kHz) and low intensity (1-3 V/cm) alternating electric fields, Tumor Treating Fields act predominantly during two phases of mitosis: 1) during metaphase, by disrupting the formation of the mitotic spindle, and 2) during cytokinesis, by dielectrophoretic dislocation of intracellular constituents resulting in apoptosis. Tumor Treating Fields cannot stimulate nerves or muscles, nor do they lead to heating of the tumor or surrounding tissues. Since Tumor Treating Fields are generated using electrically insulated electrodes (transducer arrays), there is no direct current flow into the tissue so that electrolysis and tissue damage do not occur over time. Since most normal adult brain cells proliferate very slowly, if at all, they are not affected by the Tumor Treating Fields.

The efficacy of Tumor Treating Fields is frequency dependent on specific cell types. The anti-mitotic effect of Tumor Treating Fields has been shown in multiple cell lines when the appropriate frequency was utilized. This includes but not limited to the following tumor models: glioblastoma at 200 kHz, NSCLC at 150kHz; breast carcinoma at 120kHz; melanoma at 100kHz.

Four Phase III trials of Tumor Treating Fields in a variety of solid tumors are ongoing. PANOVA-3 is Tumor Treating Fields combined with chemotherapy for newly-diagnosed pancreatic cancer. LUNAR is targeting advanced NSCLC with disease progression on or after prior platinum-based treatment, to evaluate Tumor Treating Fields combined with chemotherapy versus chemotherapy alone, METIS trial is intended for patients who have recently been diagnosed with brain metastases from NSCLC, and ENGOT-ov50/INNOVATE-3 trial is intended for patients who have recently been diagnosed with ovarian cancer that progressed and became resistant to chemotherapy containing platinum (platinum resistant ovarian cancer).

A Phase II, single arm, multi-center, open-label trial (EF-31, ZL-8301-001) to evaluate the safety and efficacy of treatment with Tumor Treating Fields and chemotherapy as first-line treatment for subjects with unresectable gastroesophageal junction (GEJ) adenocarcinoma or gastric (GC) adenocarcinoma is ongoing. This study is conducted in Hong Kong and mainland China and the first patient was dosed in January 2020. The First-Patient-In (FPI) occurred in January 2020 in Hong Kong. The initiation of enrollment in China is expected in the second half of 2020.

Optune Device Description

Optune is a portable battery or power supply operated device which act by delivering low intensity (1-3 V/cm), intermediate frequency (100-300 kHz), alternating Tumor Treating Fields to the patient’s shaved head by means of electrically insulated surface transducer arrays. It has been FDA approved for the treatment of recurrent GBM and has received CE mark for the treatment of both recurrent and newly diagnosed GBM. The device has been available commercially in the European Union and in the United States since October 2011. Optune was approved in Japan for the treatment of recurrent GBM in March 2015. The indication of Optune in the United States was expanded to include treatment of adult patients with newly diagnosed GBM in combination with TMZ in October 2015. Additionally, we commercially launched Optune in Hong Kong for the treatment of GBM in December 2018.

Indications for Optune Use

GBM, a malignant form of astrocytoma, is the most common primary intracranial neoplasm. The incidence of GBM increases steadily above 45 years of age with a prevalence of approximately 7,500 cases in the United States Despite numerous attempts to improve the outcome of patients with GBM, the 3-year survival of these patients is only 6% with median survival of 14.6 months.

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Pivotal Study of Tumor Treating Fields for Recurrent GBM Subjects

In a prospective, randomized, open label, active parallel control trial (EF-11) was conducted to compare the effectiveness and safety. A total of 237 patients (120 Optune; 117 best supportive care, BSC) with progressive or recurrent GBM were enrolled in the study. Baseline characteristics were similar between treatment groups. In the ITT population which included all randomized subjects, overall survival in subjects treated with Optune was comparable to that observed in subjects treated with BSC (median OS=6.3 vs. 6.4 months; p =0.98). The pivotal study data establish that Optune therapy is comparable to BSC therapy in extending OS.

The one-year survival is similar in the Optune and BSC groups in the ITT population (21.9% vs. 22.1%). Progression free survival at 6 months (PFS6) is the same in the ITT population (21.4% vs. 15.2%). Radiological response rates from the subset of patients evaluated were reported as 14% for the Optune group compared to 9.6% for the BSC group in the ITT population. Median time to progression, or TTP, was 9.3 weeks for Optune vs. 9.6 weeks for BSC.

Optune subjects experienced fewer adverse events in general, significantly fewer treatment related adverse events, and significantly lower gastrointestinal, hematological and infectious adverse events compared to BSC controls. The only device-related adverse event seen was a mild to moderate skin irritation beneath the device transducer arrays, which was easily treated with topical ointments. Finally, certain quality of life measures were better in Optune subjects as a group when compared to subjects receiving effective BSC chemotherapy.

Pivotal Study of Optune for Newly Diagnosed GBM

An international Phase III trial (EF-14) in newly diagnosed GBM, evaluating the role of Optune in combination with TMZ maintenance after surgery and chemoradiation versus TMZ alone was conducted between July 2009 and September 2014 to evaluate efficacy and safety.

A total of 695 patients were randomized, the median number of maintenance TMZ cycles was 6 and 5 cycles, for Optune /TMZ and TMZ alone, respectively. The median progression-free survival was 6.7 months for the patients treated with Optune /TMZ versus 4.0 months for TMZ alone (HR 0.63;95% CI 0.52-0.76; p

Based on the data, FDA expanded approval of Optune in combination with TMZ for the treatment of adult patients with newly diagnosed GBM.

Our Strategy for Tumor Treating Fields in the China Market

Given the strong clinical data from randomized control trials of Optune and its approval status in the European Union and United States in recurrent and newly diagnosed GBM, Zai Lab plans to leverage the global study data to seek potential regulatory approval in China. Zai Lab intends to participate in the ongoing global studies of Tumor Treating Fields, and will also conduct trials of Tumor Treating Fields in Chinese patients with gastric cancer.

Ripretinib

Ripretinib is an investigational KIT and PDGFRα kinase switch control inhibitor in clinical development for the treatment of KIT and/or PDGFRα-driven cancers, including GIST, systemic mastocytosis, or SM, and other cancers. Ripretinib was specifically designed to improve the treatment of GIST patients by inhibiting a broad spectrum of mutations in KIT and PDGFRα. Ripretinib is a KIT and PDGFRα inhibitor that blocks initiating and secondary KIT mutations in exons 9, 11, 13, 14, 17, and 18, involved in GIST as well as the primary D816V exon 17 mutation involved in SM. Ripretinib also inhibits primary PDGFRα mutations in exons 12, 14 and 18, including the exon 18 D842V mutation, involved in a subset of GIST.

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We obtained an exclusive license to develop and commercialize ripretinib in China, Hong Kong, Macau and Taiwan in 2019.

In December 2019, an NDA was submitted to the FDA for ripretinib in the treatment of patients with advanced GIST who have received prior treatment with imatinib, sunitinib, and regorafenib.  The NDA submission is based on positive results from our first Phase III study, INVICTUS, in fourth-line and fourth-line plus GIST patients, for whom there are currently no approved therapies other than avapritinib in the U.S. which is approved for GIST patients with PDGFRα exon 18 mutations only (estimated approximately 6% of all patients with newly-diagnosed GIST).  In August 2019, the top-line results from INVICTUS was published, including that the study achieved its primary endpoint of improved PFS compared to placebo as determined by blinded independent central radiologic review using modified RECIST.  In February 2020, the FDA accepted the NDA for ripretinib for the treatment of patients with fourth-line and fourth-line plus GIST, granted priority review and set an action date of August 13, 2020 under the PDUFA.

Our Clinical Trial Designs and Strategy for ripretinib in the China Market

Zai Lab will seek regulatory approval for ripretinib in China using data from global studies and China bridging studies.  In February 2020, Zai Lab received the NMPA approval to conduct the bridging study in > 4L GIST. In additional, Zai Lab also plans to conduct a 2L bridging study in the GIST patients in China.

Ripretinib Mechanism of Action

KIT and PDGFRα are dual switch kinases, each containing i) an auxiliary inhibitory switch encoded by KIT exon 11 or PDGFRα exon 12 and ii) a main activation loop switch within the kinase domain encoded by KIT exons 17 and 18 or PDGFRα exons 18 and 19. This dual switch mechanism carefully regulates cellular kinase activity by controlling kinase conformation in either an "on" or "off" position. Oncogenic kinase mutations predominantly function by disrupting one or more regulatory switch mechanisms, leading to dysregulated switch function and loss of normal, physiologic conformational control. Ripretinib is a novel switch-control tyrosine kinase inhibitor (TKI) specifically designed to broadly inhibit KIT and PDGFRα kinase signaling through a dual mechanism of action that locks the kinase into an inactive conformation, resulting in inhibition of downstream signaling and cell proliferation.

Ripretinib precisely and durably binds to both the switch pocket region and the activation loop to lock the kinase in the inactive "off" state. Portions of ripretinib mimic the inhibitory loop and occupy the switch pocket, thereby preventing the activation loop's entry. Other residues on ripretinib bind to the activation loop, stabilizing it out of the switch pocket and covering the adenosine triphosphate (ATP) binding site, so kinase activation cannot occur.

This dual mechanism of action secures KIT and PDGFRα kinases in their inactive conformations providing broad in vitro inhibition of KIT and PDGFRα kinase activity, including wild type and multiple primary and secondary mutations. Ripretinib also inhibits other kinases in vitro, such as PDGFRβ, TIE2, VEGFR2, and BRAF.

Gastrointestinal Stromal Tumors (GIST)

GISTs are the most common sarcoma of the gastrointestinal tract and present most often in the stomach or small intestine. The typical patient is over 50 years old. According to the American Cancer Society, in 2019 approximately 4,000 to 6,000 patients were newly diagnosed with GIST in the U.S. Estimates for 5-year survival range from 48% to 90% depending upon the stage of the disease at diagnosis.

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GIST is a disease driven initially by primary mutations in KIT kinase in approximately 75% to 80% of cases or in PDGFRα kinase in approximately 5% to 10% of cases. In approximately 13% of all GIST patients, the disease is not driven by KIT or PDGFRα but by other genetic mutations or alterations. Primary mutations in the KIT gene are found in exon 11 in approximately 67% of GIST patients, in exon 9 in approximately 10% of GIST patients, and less frequently in exon 13 or 17. Primary mutations in the PDGFRα gene are found in exon 18 (a mutation referred to as D842V being the most frequent) in approximately 6% of GIST patients and more rarely in exon 12. Activation of these kinases caused by primary mutations leads to uncontrolled cancer cell growth and spread. The diagram below illustrates the mutations that drive GIST:

Metastatic KIT-driven GIST is a disease characterized by many mutations in KIT, with over 90% of individual KIT-driven GIST patients harboring multiple mutations that drive progression of their disease. Multiple secondary mutations can arise within an individual patient and/or tumor in different areas or sites of tumor growth. Drug resistant secondary mutations in patients with KIT-driven GIST span exon regions 13 to 18, and in a recent study, 35% of GIST patients had at least two secondary mutations, each as illustrated below.

The complex heterogeneity of KIT mutations within individual tumors and individual patients is a major cause of resistance to existing therapies, which individually only address a subset of the mutations driving disease progression. A kinase inhibitor that could inhibit a broad spectrum of clinically relevant KIT mutations could be of high therapeutic value in the treatment of KIT-driven GIST in patients who are unresponsive to treatment or have grown resistant to treatment. In PDGFRα-driven GIST, there are no approved therapies other than avapritinib. The primary PDGFRα mutations are mostly insensitive to imatinib and other drugs approved for GIST. The design of ripretinib as a PDGFRα switch control inhibitor may make the appearance of secondary mutations less likely after treatment than with a traditional kinase inhibitor.

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The following table shows reported PFS or TTP (as applicable), ORR, overall survival, all as per RECIST, for imatinib, sunitinib, and regorafenib in first-line, second-line, and third-line GIST, respectively, based upon the published results of registrational trials that were presented to the FDA for approval of these drugs.

While imatinib, sunitinib, and regorafenib inhibit certain clinically relevant initiating and drug resistance-causing mutations in KIT, these approved drugs, in addition to avapritinib, each inhibit only a limited subset of KIT and PDGFRα mutations known to occur in GIST patients. Although GIST patients may experience periods of disease control with these treatments, due to the heterogeneous nature of the mutations that drive the disease, many patients continue to progress and ultimately fail all lines of treatment.

Clinical development of Ripretinib in GIST

INVICTUS: Completed Phase III Study in Fourth-Line and Fourth-Line Plus GIST

The INVICTUS Phase III study was a randomized, double-blind, placebo-controlled, global, multicenter trial to evaluate the safety, tolerability, and efficacy of ripretinib compared to placebo in patients with advanced GIST whose previous therapies have included at least imatinib, sunitinib, and regorafenib. The trial enrolled 129 patients who had a confirmed diagnosis of GIST and had previously received at least three different kinase inhibitors including imatinib, sunitinib, and regorafenib. Patients were treated with ripretinib or placebo, in accordance with their randomization, until they developed disease progression, experienced unacceptable toxicity, or withdrew consent. Placebo patients had the opportunity to cross over to ripretinib treatment upon disease progression with placebo. Patients on ripretinib had the opportunity to remain on their current dose or escalate to 150 mg twice daily (BID) upon disease progression.

Patients were randomized 2:1 to either 150 mg of ripretinib or placebo once daily (QD) in repeated 28-day cycles with best supportive care. Patients were evaluated for PFS based upon independent radiologic review of CT scans, as assessed by modified RECIST. Tumor response assessments per modified RECIST were conducted every cycle for the first three cycles and then every two cycles thereafter beginning with the fourth cycle. The primary efficacy endpoint was PFS as determined by independent radiologic review using modified RECIST. Secondary endpoints as determined by independent radiologic review using modified RECIST included ORR, overall survival (OS), and TTP.

In 2019, the top-line results from INVICTUS is published, including that the study achieved its primary endpoint of improved PFS compared to placebo.

In the INVICTUS study, ripretinib demonstrated a median PFS of 6.3 months (27.6 weeks) compared to 1.0 month (4.1 weeks) in the placebo arm and significantly reduced the risk of disease progression or death by 85% (Hazard Ratio (HR) of 0.15, 95% Confidence Interval (0.09,0.25), p-value The following graph shows the estimated PFS probability at each time point for the ripretinib and placebo arms in INVICTUS:

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INVICTUS: Estimated PFS Probability for Ripretinib and Placebo Arms

*Double-blind period

For the key secondary endpoint of ORR as determined by blinded independent radiologic review using modified RECIST, ripretinib demonstrated an ORR of 9.4% compared with 0% for placebo (p-value=0.0504), which was not statistically significant. As of the cutoff date of May 31, 2019, the median duration of response had not been reached with seven of the eight patients still responding to treatment. All responders had partial responses.

Ripretinib also showed a clinically meaningful improvement over placebo in terms of the secondary endpoint of OS (median OS 15.1 months with ripretinib compared to 6.6 months with placebo, HR = 0.36, 95% Confidence Interval (0.20,0.62), nominal p-value=0.0004). The OS data for the placebo arm includes patients taking placebo who, following progression, were crossed-over to ripretinib treatment. The following graph shows the estimated OS probability at each time point for the ripretinib and placebo arms in INVICTUS:

INVICTUS: Estimated OS Probability for Ripretinib and Placebo Arms

*Due to hierarchal testing procedures of the endpoints, the OS endpoint could not be formally tested because the ORR was not statistically significant.

† Data includes all time periods, including dose escalations. Placebo arm includes patients taking placebo who, following progression, were crossed-over to ripretinib treatment.

Ripretinib was generally well tolerated and the adverse events reported in the INVICTUS study were consistent with data from previously presented Phase I study results. Grade 3 or 4 treatment-emergent adverse events (TEAEs) occurred in 42 patients (49%) on the ripretinib arm compared to 19 patients (44%) on the placebo arm. Grade 3 or 4 TEAEs in greater than 5% of patients in the ripretinib arm were anemia (9%; n=8), abdominal pain (7%; n=6), and hypertension (7%; n=6). Grade 3 or 4 TEAEs in greater than 5% of patients in the placebo arm were anemia (14%; n=6).

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The below table lists all TEAEs (and corresponding grade 3 and 4 TEAEs) in greater than 10% of patients in the ripretinib arm compared to the placebo arm in INVICTUS.

INVICTUS: TEAEs in >10% of Patients

(and Corresponding Grade 3 and 4 TEAEs)