ZLAB Zai Lab Ltd

Exhibit 1.1

ZAI LAB LIMITED

78,431,370 ORDINARY SHARES, PAR VALUE $0.000006 PER SHARE

in the form of 7,843,137 American Depositary Shares

Underwriting Agreement

November 14, 2024

Goldman Sachs (Asia) L.L.C.

Jefferies LLC

Leerink Partners LLC

As Representatives of the

several Underwriters listed

in Schedule 1 hereto

c/o Goldman Sachs (Asia) L.L.C.

68^th Floor, Cheung Kong Center

2 Queen’s Road Central

Hong Kong

c/o Jefferies LLC

520 Madison Avenue

New York, New York 10022

c/o Leerink Partners LLC

1301 Avenue of the Americas, 5th Floor

New York, New York 10019

Ladies and Gentlemen:

Zai Lab Limited, an exempted company incorporated with limited liability under the laws of the Cayman Islands (the “Company”), proposes to issue and sell to the several underwriters listed in Schedule 1 hereto (the “Underwriters”), for whom you are acting as representatives (the “Representatives”), an aggregate of 7,843,137 American Depositary Shares (“ADSs”), representing 78,431,370 ordinary shares, par value $0.000006 per share (the “Ordinary Shares”), of the Company (the “Underwritten ADSs”). In addition, the Company proposes to issue and sell, at the option of the Underwriters, up to an additional 1,176,470 ADSs, representing 11,764,700 Ordinary Shares (the “Option ADSs”). The Underwritten ADSs and the Option ADSs are herein referred to as the “Offered ADSs.” The Ordinary Shares represented by the Underwritten ADSs are herein referred to as the “Underwritten Shares,” the Ordinary Shares represented by the Option ADSs are herein referred to as the “Option Shares” and the Underwritten Shares and the Option Shares are herein referred to as the “Shares.” To the extent there are no additional underwriters listed on Schedule 1, the term “Representatives” as used herein shall mean you, as Underwriter, and the term “Underwriters” shall mean either the singular or the plural, as the context requires.

The Offered ADSs are to be issued pursuant to the deposit agreement (the “Deposit Agreement”), dated as of September 20, 2017, among the Company, Citibank, N.A. (the “Depositary”), as depositary, and owners and beneficial owners from time to time of the ADSs. Each Offered ADS will initially represent the right to receive one (1) Ordinary Share deposited pursuant to the Deposit Agreement.

The Company hereby confirms its agreement with the several Underwriters concerning the purchase and sale of the Offered ADSs, as follows:

1. Registration Statement. The Company has prepared and filed with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Securities Act”), a registration statement on Form S-3 (File No. 333-278843), including a prospectus, relating to the Shares. Such registration statement, as amended at the time it became effective, including the information, if any, deemed pursuant to Rule 430A, 430B or 430C under the Securities Act to be part of the registration statement at the time of its effectiveness (“Rule 430 Information”), is referred to herein as the “Registration Statement”; and as used herein, the term “Preliminary Prospectus” means each prospectus included in such registration statement (and any amendments thereto) before effectiveness, any prospectus filed with the Commission pursuant to Rule 424(a) under the Securities Act and the prospectus included in the Registration Statement at the time of its effectiveness that omits Rule 430 Information, and the term “Prospectus” means the prospectus in the form first used (or made available upon request of purchasers pursuant to Rule 173 under the Securities Act) in connection with confirmation of sales of the Offered ADSs. If the Company has filed an abbreviated registration statement pursuant to Rule 462(b) under the Securities Act (the “Rule 462 Registration Statement”), then any reference herein to the term “Registration Statement” shall be deemed to include such Rule 462 Registration Statement. Any reference in this underwriting agreement (this “Agreement”) to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include the documents incorporated by reference therein pursuant to Item 12 of Form S-3 under the Securities Act, as of the effective date of the Registration Statement or the date of such Preliminary Prospectus or the Prospectus, as the case may be, and any reference to “amend,” “amendment” or “supplement” with respect to the Registration Statement, any Preliminary Prospectus or the Prospectus shall be deemed to refer to and include any documents filed after such date under the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission thereunder (collectively, the “Exchange Act”) that are deemed to be incorporated by reference therein. Capitalized terms used but not defined herein shall have the meanings given to such terms in the Registration Statement and the Prospectus.

At or prior to the Applicable Time (as defined below), the Company had prepared the following information (collectively with the pricing information set forth on Annex A, the “Pricing Disclosure Package”): a Preliminary Prospectus dated November 13, 2024 and each “free-writing prospectus” (as defined pursuant to Rule 405 under the Securities Act) listed on Annex A hereto.

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“Applicable Time” means 6:15 P.M., New York City time, on November 14, 2024.

2. Purchase of the Offered ADSs.

(a) The Company agrees to issue and sell the Underwritten ADSs to the several Underwriters as provided in this Agreement, and each Underwriter, on the basis of the representations, warranties and agreements set forth herein and subject to the conditions set forth herein, agrees, severally and not jointly, to purchase from the Company the respective number of Underwritten ADSs set forth opposite such Underwriter’s name in Schedule 1 hereto at a price per ADS (the “Purchase Price”) of $24.0975.

In addition, the Company agrees to issue and sell the Option ADSs to the several Underwriters as provided in this Agreement, and the Underwriters, on the basis of the representations, warranties and agreements set forth herein and subject to the conditions set forth herein, shall have the option to purchase, severally and not jointly, from the Company the Option ADSs at the Purchase Price less an amount per ADS equal to any dividends or distributions declared by the Company and payable on the Underwritten ADSs but not payable on the Option ADSs.

If any Option ADSs are to be purchased, the number of Option ADSs to be purchased by each Underwriter shall be the number of Option ADSs which bears the same ratio to the aggregate number of Option ADSs being purchased as the number of Underwritten ADSs set forth opposite the name of such Underwriter in Schedule 1 hereto (or such number increased as set forth in Section 12 hereof) bears to the aggregate number of Underwritten ADSs being purchased from the Company by the several Underwriters, subject, however, to such adjustments to eliminate any fractional ADSs, as applicable, as Goldman Sachs (Asia) L.L.C. and Jefferies LLC in their sole discretion shall make. Any such election to purchase Option ADSs shall be made in proportion to the maximum number of Option ADSs to be sold by the Company.

The Underwriters may exercise the option to purchase Option ADSs at any time in whole, or from time to time in part, on or before the thirtieth day following the date of the Prospectus, by written notice from Goldman Sachs (Asia) L.L.C. and Jefferies LLC to the Company. Such notice shall set forth the aggregate number of Option ADSs as to which the option is being exercised and the date and time when the Option ADSs are to be delivered and paid for, which may be the same date and time as the Closing Date (as hereinafter defined) but shall not be earlier than the Closing Date nor later than the tenth full business day (as hereinafter defined) after the date of such notice (unless such time and date are postponed in accordance with the provisions of Section 12 hereof). Any such notice shall be given at least two business days prior to the date and time of delivery specified therein.

(b) The Company understands that the Underwriters intend to make a public offering of the Offered ADSs as soon as after the effectiveness of this Agreement as in the judgment of the Representatives is advisable, and initially to offer the Offered ADSs on the terms set forth in the Pricing Disclosure Package. The Company acknowledges and agrees that the Underwriters may offer and sell Offered ADSs to or through any affiliate of an Underwriter.

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(c) Payment for the Offered ADSs shall be made by wire transfer in immediately available funds to the accounts specified by the Company to the Representatives in the case of the Underwritten ADSs at the offices of Simpson Thacher & Bartlett LLP, 425 Lexington Avenue, New York, New York 10017 at 10:00 A.M., New York City time, on November 18, 2024, or at such other time or place on the same or such other date, not later than the fifth business day thereafter, as the Representatives and the Company may agree upon in writing or, in the case of the Option ADSs, on the date and at the time and place specified by Goldman Sachs (Asia) L.L.C. and Jefferies LLC in the written notice of the Underwriters’ election to purchase such Option ADSs. The time and date of such payment for the Underwritten ADSs is referred to herein as the “Closing Date,” and the time and date for such payment for the Option ADSs, if other than the Closing Date, is herein referred to as the “Additional Closing Date.”

Payment for the Offered ADSs to be purchased on the Closing Date or the Additional Closing Date, as the case may be, shall be made against delivery to the Representatives for the respective accounts of the several Underwriters of the Offered ADSs to be purchased on such date or the Additional Closing Date, as the case may be, with any transfer taxes payable in connection with the sale of such Offered ADSs duly paid by the Company. Delivery of the Offered ADSs shall be made through the facilities of The Depository Trust Company unless the Representatives shall otherwise instruct.

(d) The Company acknowledges and agrees that the Representatives and the other Underwriters are acting solely in the capacity of an arm’s length contractual counterparty to the Company with respect to the offering of the Offered ADSs contemplated hereby (including in connection with determining the terms of the offering) and not as a financial advisor or a fiduciary to, or an agent of, the Company or any other person. Additionally, neither the Representatives nor any other Underwriter is advising the Company or any other person as to any legal, tax, investment, accounting or regulatory matters in any jurisdiction. The Company shall consult with its own advisors concerning such matters and each shall be responsible for making its own independent investigation and appraisal of the transactions contemplated hereby, and neither the Representatives nor any other Underwriter shall have any responsibility or liability to the Company with respect thereto. Any review by the Representatives and the other Underwriters of the Company, the transactions contemplated hereby or other matters relating to such transactions will be performed solely for the benefit of the Representatives and the other Underwriters and shall not be on behalf of the Company.

3. Representations and Warranties of the Company. The Company represents and warrants to each Underwriter that:

(a) Preliminary Prospectus. No order preventing or suspending the use of any Preliminary Prospectus has been issued by the Commission, and each Preliminary Prospectus included in the Pricing Disclosure Package, at the time of filing thereof, complied in all material respects with the Securities Act, and no Preliminary Prospectus, at the time of filing thereof, contained any untrue statement of a material fact or omitted to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided, that the Company makes no representation or warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in any Preliminary Prospectus, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 9(c) hereof.

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(b) Pricing Disclosure Package. The Pricing Disclosure Package as of the Applicable Time did not, and as of the Closing Date and as of the Additional Closing Date, as the case may be, will not, contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided, that the Company makes no representation or warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in such Pricing Disclosure Package, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 9(c) hereof.

(c) Issuer Free Writing Prospectus. Other than the Registration Statement, the Preliminary Prospectus and the Prospectus, the Company (including its agents and representatives, other than the Underwriters in their capacity as such) has not prepared, made, used, authorized, approved or referred to and will not prepare, make, use, authorize, approve or refer to any “written communication” (as defined in Rule 405 under the Securities Act) that constitutes an offer to sell or solicitation of an offer to buy the Offered ADSs (each such communication by the Company or its agents and representatives (other than a communication referred to in clause (i) below) an “Issuer Free Writing Prospectus”) other than (i) any document not constituting a prospectus pursuant to Section 2(a)(10)(a) of the Securities Act or Rule 134 under the Securities Act or (ii) the documents listed on Annex A hereto, each electronic road show and any other written communications approved in writing in advance by the Representatives. Each such Issuer Free Writing Prospectus complies in all material respects with the Securities Act, has been or will be (within the time period specified in Rule 433) filed in accordance with the Securities Act (to the extent required thereby) and does not conflict with the information contained in the Registration Statement or the Pricing Disclosure Package., when taken together with the Preliminary Prospectus accompanying, or delivered prior to or subsequent to delivery of, such Issuer Free Writing Prospectus, at the Applicable Time, did not, and as of the Closing Date and as of the Additional Closing Date, as the case may be, will not, contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided, that the Company makes no representation or warranty with respect to any statements or omissions made in each such Issuer Free Writing Prospectus or Preliminary Prospectus in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in such Issuer Free Writing Prospectus or Preliminary Prospectus, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 9(c) hereof.

(d) [Reserved.]

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(e) Registration Statement and Prospectus. The Registration Statement is an “automatic shelf registration statement” as defined under Rule 405 of the Securities Act that has been filed with the Commission not earlier than three years prior to the date hereof; and no notice of objection of the Commission to the use of such registration statement or any post-effective amendment thereto pursuant to Rule 401(g)(2) under the Securities Act has been received by the Company. No order suspending the effectiveness of the Registration Statement has been issued by the Commission, and, to the knowledge of the Company, no proceeding for that purpose or pursuant to Section 8A of the Securities Act against the Company or related to the offering of the Offered ADSs has been initiated or threatened by the Commission; as of the applicable effective date of the Registration Statement and any post-effective amendment thereto, the Registration Statement and any such post-effective amendment complied and will comply in all material respects with the Securities Act, and did not and will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein not misleading; and as of the date of the Prospectus and any amendment or supplement thereto and as of the Closing Date and as of the Additional Closing Date, as the case may be, the Prospectus will comply in all material respects with the Securities Act and will not contain any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading; provided, that the Company makes no representation or warranty with respect to any statements or omissions made in reliance upon and in conformity with information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in the Registration Statement and the Prospectus and any amendment or supplement thereto, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 9(c) hereof.

(f) Form F-6. A registration statement on Form F-6 (File No. 333-220256), and any amendments thereto, in respect of the Offered ADSs has been filed with the Commission; such registration statement in the form heretofore delivered to the Representatives and, excluding exhibits, to the Representatives for each of the other Underwriters, has been declared effective by the Commission; no other document with respect to such registration statement has heretofore been filed with the Commission; no stop order suspending the effectiveness of such registration statement has been issued and, to the knowledge of the Company, no proceeding for that purpose has been initiated or threatened by the Commission (the various parts of such registration statement, including all exhibits thereto, each as amended at the time such part of the registration statement became effective, being hereinafter called the “ADS Registration Statement”); and the ADS Registration Statement when it became effective complied, and any further amendments thereto will comply, in all material respects with the Securities Act, and did not, as of the applicable effective date, and will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein not misleading.

(g) Form 8-A. A registration statement on Form 8-A (File No. 001-38205), and any amendments thereto, in respect of the registration of the Offered ADSs under the Exchange Act has been filed with the Commission; such registration statement in the form heretofore delivered to the Representatives and, excluding exhibits, to the Representatives for each of the other Underwriters, has been declared effective by the Commission; no other

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document with respect to such registration statement has heretofore been filed with the Commission; no stop order suspending the effectiveness of such registration statement has been issued and, to the knowledge of the Company, no proceeding for that purpose has been initiated or threatened by the Commission (the various parts of such registration statement, including all exhibits thereto, each as amended at the time such part of the registration statement became effective, being hereinafter called the “Form 8-A Registration Statement”); and the Form 8-A Registration Statement when it became effective complied, and any further amendments thereto will comply, in all material respects with the Exchange Act, and did not, as of the applicable effective date, and will not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary in order to make the statements therein not misleading.

(h) Incorporated Documents. The documents incorporated by reference in the Registration Statement, the Prospectus and the Pricing Disclosure Package, when they were filed with the Commission, conformed in all material respects to the requirements of the Exchange Act, and none of such documents contained any untrue statement of a material fact or omitted to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; and any further documents so filed and incorporated by reference in the Registration Statement, the Prospectus or the Pricing Disclosure Package, when such documents are filed with the Commission, will conform in all material respects to the requirements of the Exchange Act and will not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading.

(i) Financial Statements. The financial statements (including the related notes thereto) of the Company and its consolidated subsidiaries included or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus comply in all material respects with the applicable requirements of the Securities Act and the Exchange Act, as applicable, and present fairly the financial position of the Company and its consolidated subsidiaries as of the dates indicated and the results of their operations and the changes in their cash flows for the periods specified; such financial statements have been prepared in conformity with generally accepted accounting principles (“GAAP”) in the United States applied on a consistent basis throughout the periods covered thereby, except as otherwise disclosed therein and, in the case of unaudited, interim financial statements, subject to normal year-end audit adjustments and the exclusion of certain footnotes as permitted by the applicable rules of the Commission, and any supporting schedules included or incorporated by reference in the Registration Statement present fairly the information required to be stated therein; and the other financial information included or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus has been derived from the accounting records of the Company and its consolidated subsidiaries and presents fairly the information shown thereby. The Registration Statement, the Pricing Disclosure Package and the Prospectus do not contain any “non-GAAP financial measures” (as such term is defined by the rules and regulations of the Commission).

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(j) No Material Adverse Change. Since the date of the most recent financial statements of the Company included or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus, (i) there has not been any material change in the capital stock (other than the issuance of Ordinary Shares upon exercise of stock options and warrants described as outstanding in, and the grant of options and awards under existing equity incentive plans described in, the Registration Statement, the Pricing Disclosure Package and the Prospectus), short-term debt or long-term debt of the Company or any of its subsidiaries, or any dividend or distribution of any kind declared, set aside for payment, paid or made by the Company on any class of capital stock, or any material adverse change, or any development that would reasonably be expected to result in a prospective material adverse change, in or affecting the business, properties, management, financial position, stockholders’ equity or results of operations of the Company and its subsidiaries taken as a whole; (ii) except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, neither the Company nor any of its subsidiaries has entered into any transaction or agreement (whether or not in the ordinary course of business) that is material to the Company and its subsidiaries taken as a whole or incurred any liability or obligation, direct or contingent, that is material to the Company and its subsidiaries taken as a whole; and (iii) neither the Company nor any of its subsidiaries taken as a whole has sustained any loss or interference with its business that is material to the Company and its subsidiaries taken as a whole and that is either from fire, explosion, flood or other calamity, whether or not covered by insurance, or from any labor disturbance or dispute or any action, order or decree of any court or arbitrator or governmental or regulatory authority, except in each case as otherwise disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(k) Organization and Good Standing. The Company and each of its subsidiaries have been duly organized and are validly existing and in good standing (where such concept exists) under the laws of their respective jurisdictions of organization, are duly qualified to do business and are in good standing in each jurisdiction in which their respective ownership or lease of property or the conduct of their respective businesses requires such qualification, and have all power and authority necessary to own or hold their respective properties and to conduct the businesses in which they are engaged, except where the failure to be so qualified or in good standing or have such power or authority would not, individually or in the aggregate, have a material adverse effect on the business, properties, management, financial position, stockholders’ equity, results of operations or prospects of the Company and its subsidiaries taken as a whole or on the performance by the Company of its obligations under the Transaction Documents (as defined below) (a “Material Adverse Effect”). All their constitutional documents comply in all material respects with the requirements of applicable laws of jurisdictions of their incorporation or organization and are in full force and effect. The Company does not own or control, directly or indirectly, any corporation, association or other entity other than the subsidiaries listed in Exhibit 21.1 to the Annual Report on Form 10-K for the year ended December 31, 2023, filed with the Commission on February 27, 2024.

(l) Capitalization. The Company has an authorized capitalization as set forth in the Registration Statement, the Pricing Disclosure Package and the Prospectus under the heading “Capitalization;” all the outstanding shares of capital stock of the Company have been duly and validly authorized and issued and are fully paid and non-assessable and are not subject to any pre-emptive or similar rights; except as described in or expressly contemplated by the Registration Statement, the Pricing Disclosure Package and the Prospectus, there are no outstanding rights (including, without limitation, pre-emptive rights), warrants or options to acquire, or instruments convertible into or exchangeable for, any shares of capital stock or other

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equity interest in the Company or any of its subsidiaries, or any contract, commitment, agreement, understanding or arrangement of any kind relating to the issuance of any capital stock of the Company or any such subsidiary, any such convertible or exchangeable securities or any such rights, warrants or options; the capital stock of the Company conforms in all material respects to the description thereof contained in the Registration Statement, the Pricing Disclosure Package and the Prospectus; and all the outstanding shares of capital stock or other equity interests of each subsidiary owned, directly or indirectly, by the Company have been duly and validly authorized and issued, are fully paid and non-assessable and are owned directly or indirectly by the Company, free and clear of any lien, charge, encumbrance, security interest, restriction on voting or transfer or any other claim of any third party.

(m) Stock Options and Restricted Stock. With respect to the stock options (the “Stock Options”) and shares of restricted stock granted pursuant to the stock-based compensation plans of the Company and its subsidiaries (the “Company Stock Plans”), (i) each Stock Option intended to qualify as an “incentive stock option” under Section 422 of the Code so qualifies, (ii) each grant of a Stock Option and issuance of restricted stock was duly authorized no later than the date on which the grant of such Stock Option or issuance of restricted stock was by its terms to be effective by all necessary corporate action, including, as applicable, approval by the board of directors of the Company (or a duly constituted and authorized committee thereof) and any required stockholder approval by the necessary number of votes or written consents, and the award agreement governing such grant or issuance (if any) was duly executed and delivered by each party thereto, (iii) each such grant or issuance was made in accordance with the terms of the Company Stock Plans, the Exchange Act and all other applicable laws and regulatory rules or requirements, including the rules of the Nasdaq Global Market (the “Nasdaq Exchange”) and any other exchange on which the Company securities are traded and (iv) each such grant or issuance was properly accounted for in accordance with GAAP in the financial statements (including the related notes) of the Company and disclosed in the Company’s filings with the Commission in accordance with the Exchange Act and all other applicable laws. The Company has not knowingly granted, and there is no and has been no policy or practice of the Company of granting, Stock Options prior to, or otherwise coordinating the grant of Stock Options with, the release or other public announcement of material information regarding the Company or its subsidiaries or their results of operations or prospects.

(n) Due Authorization. The Company has full right, power and authority to execute and deliver this Agreement and to perform its obligations hereunder and thereunder; and all action required to be taken for the due and proper authorization, execution and delivery by it of this Agreement and the consummation by it of the transactions contemplated hereby has been duly and validly taken.

(o) Underwriting Agreement. This Agreement has been duly authorized, executed and delivered by the Company.

(p) The Shares. The Shares to be issued and sold by the Company hereunder have been duly authorized by the Company and, when issued and delivered and paid for as provided herein, will be duly and validly issued, will be fully paid and nonassessable and will conform in all material respects to the descriptions thereof in the Registration Statement, the Pricing Disclosure Package and the Prospectus; and the issuance of the Shares is not subject to

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any preemptive or similar rights. The Shares may be freely deposited by the Company with the Depositary against issuance of the Offered ADSs; the Offered ADSs to be sold by the Company, when issued and delivered against payment thereof, will be freely transferable by the Company to or for the account of the several Underwriters and (to the extent described in the Prospectus) the initial purchasers thereof; and there are no restrictions on subsequent transfers of the Offered ADSs under the laws of the Cayman Islands, the People’s Republic of China, which, for purposes of this Agreement only, excludes Taiwan, The Hong Kong Special Administrative Region and The Macau Special Administrative Region (the “PRC”) or the United States except as disclosed or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus under “Description of share capital.”

(q) Deposit Agreement. The Deposit Agreement (together with this Agreement, the “Transaction Documents”) was duly authorized and executed by the Company and delivered in accordance with its terms by each of the parties thereto and constitutes a valid and legally binding agreement of the Company enforceable against the Company in accordance with its terms, except as enforceability may be limited by applicable bankruptcy, insolvency, reorganization or similar laws affecting the enforcement of creditors’ rights generally or by equitable principles relating to enforceability.

(r) Descriptions of the Transaction Documents. Each Transaction Document conforms in all material respects to the description thereof contained in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(s) No Violation or Default. Neither the Company nor any of its subsidiaries is (i) in violation of its charter or by-laws or similar organizational documents; (ii) in default, and no event has occurred that, with notice or lapse of time or both, would constitute such a default, in the due performance or observance of any term, covenant or condition contained in any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any property or asset of the Company or any of its subsidiaries is subject; or (iii) in violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory authority having jurisdiction over the Company or any of its subsidiaries, including the China Securities Regulatory Commission (“CSRC”), except, in the case of clauses (ii) and (iii) above, for any such default or violation that would not, individually or in the aggregate, have a Material Adverse Effect.

(t) No Conflicts. The execution, delivery and performance by the Company of each of the Transaction Documents, the issuance and sale of the Offered ADSs by the Company and the consummation by the Company of the transactions contemplated by the Transaction Documents will not (i) conflict with or result in a breach or violation of any of the terms or provisions of, or constitute a default under, result in the termination, modification or acceleration of, or result in the creation or imposition of any lien, charge or encumbrance upon any property, right or asset of the Company or any of its subsidiaries pursuant to, any indenture, mortgage, deed of trust, loan agreement or other agreement or instrument to which the Company or any of its subsidiaries is a party or by which the Company or any of its subsidiaries is bound or to which any property, right or asset of the Company or any of its subsidiaries is subject, (ii) result in any violation of the provisions of the charter or by-laws or similar organizational

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documents of the Company or any of its subsidiaries or (iii) result in the violation of any law or statute or any judgment, order, rule or regulation of any court or arbitrator or governmental or regulatory authority, except, in the case of clauses (i) and (iii) above, for any such conflict, breach, violation, default, lien, charge or encumbrance that would not, individually or in the aggregate, have a Material Adverse Effect.

(u) No Consents Required. No consent, approval, authorization, order, registration or qualification of or with any court or arbitrator or governmental or regulatory authority is required for the execution, delivery and performance by the Company of each of the Transaction Documents, the issuance and sale of the Offered ADSs and the consummation of the transactions contemplated by the Transaction Documents, except for the registration of the Offered ADSs under the Securities Act and such consents, approvals, authorizations, orders and registrations or qualifications as have already been made or as may be required by the Financial Industry Regulatory Authority, Inc. (“FINRA”), the Nasdaq Exchange, the Stock Exchange of Hong Kong Limited (the “HK Exchange”) or under applicable state securities laws in connection with the purchase and distribution of the Offered ADSs by the Underwriters.

(v) Legal Proceedings. Except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, there are no legal, governmental or regulatory investigations, actions, demands, claims, suits, arbitrations, inquiries or proceedings (“Actions”) pending to which the Company or any of its subsidiaries is or, to the Company’s knowledge, may be a party, or any of its executive officers, directors or key employees is a party, or to which any property or rights of the Company or any of its subsidiaries is or, to the Company’s knowledge, may be the subject that, individually or in the aggregate, if determined adversely to the Company or any of its subsidiaries, would reasonably be expected to have a Material Adverse Effect; to the knowledge of the Company, no such Actions are threatened or contemplated by any governmental or regulatory authority or threatened by others; and (i) there are no current or pending Actions that are required under the Securities Act to be described in the Registration Statement, the Pricing Disclosure Package or the Prospectus, that are not so described in the Registration Statement, the Pricing Disclosure Package and the Prospectus and (ii) there are no statutes, regulations or contracts or other documents that are required under the Securities Act to be filed as exhibits to the Registration Statement or described in the Registration Statement, the Pricing Disclosure Package or the Prospectus, that are not so filed as exhibits to the Registration Statement or described in the Registration Statement, the Pricing Disclosure Package and the Prospectus.

(w) Independent Accountants. KPMG LLP, who have audited certain financial statements of the Company and its subsidiaries, is an independent registered public accounting firm with respect to the Company and its subsidiaries within the applicable rules and regulations adopted by the Commission and the Public Company Accounting Oversight Board (United States) and as required by the Securities Act. Deloitte Touche Tohmatsu Certified Public Accountants LLP, who have audited certain financial statements of the Company and its subsidiaries for the fiscal year ended 2021, was an independent registered public accounting firm with respect to the Company and its subsidiaries within the applicable rules and regulations adopted by the Commission and the Public Company Accounting Oversight Board (United States) and as required by the Securities Act at the time they delivered their report with respect to the audited financial statements for such fiscal years.

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(x) Title to Real and Personal Property. The Company and its subsidiaries have valid rights to lease or otherwise use, all items of real and personal property that are material to the respective businesses of the Company and its subsidiaries taken as a whole, in each case free and clear of all liens, encumbrances, claims and defects and imperfections of title except those that (i) do not materially interfere with the use made and proposed to be made of such property by the Company and its subsidiaries or (ii) would not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect.

(y) Intellectual Property. Except as disclosed in the Registration Statement, the Pricing Disclosure Package or the Prospectus, and except as would not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect, (i) the Company and its subsidiaries own or possess valid and adequate rights to use or can acquire on reasonable terms all patents, inventions, trademarks, service marks, trade names, domain names and other source indicators, copyrights and copyrightable works, licenses, technology, know-how (including trade secrets and other unpatented and/or unpatentable proprietary or confidential information, systems or procedures), proprietary or confidential information and all other intellectual property and proprietary rights (including all registrations, applications for registration and goodwill associated with the foregoing) (collectively, “Intellectual Property”), in each case, used in, held for use in or otherwise necessary for the conduct of their respective businesses as currently conducted and as proposed to be conducted in the Registration Statement, the Pricing Disclosure Package or the Prospectus; (ii) there are no rights of third parties to any Intellectual Property owned by or licensed to the Company and its subsidiaries that would prevent the Company or its subsidiaries from continuing their business as currently conducted and as proposed to be conducted in the Registration Statement, the Pricing Disclosure Package or the Prospectus; (iii) the Company’s and its subsidiaries’ conduct of their respective businesses does not infringe, misappropriate or otherwise violate, and has not infringed, misappropriated or otherwise violated, any Intellectual Property of any person; (iv) neither the Company nor any of its subsidiaries has received any notice of any Action relating to Intellectual Property, including any claim of infringement, misappropriation, breach, default or other violation of any Intellectual Property of any person, or any notice challenging the ownership, validity, enforceability or scope of any Intellectual Property of the Company or any of its subsidiaries; and (v) to the knowledge of the Company, all Intellectual Property of the Company and its subsidiaries is valid, enforceable and has not been, and is not currently being, infringed, misappropriated or otherwise violated by any person.

(z) No Undisclosed Relationships. No relationship, direct or indirect, exists between or among the Company or any of its subsidiaries, on the one hand, and the directors, officers, shareholders, customers or suppliers or other affiliates of the Company or any of its subsidiaries, on the other hand, that is required by the Securities Act or the listing rules of the Nasdaq Exchange and/or the HK Exchange (“Listing Rules”) to be described in each of the Registration Statement and the Prospectus and that is not so described in such documents and in the Pricing Disclosure Package.

(aa) Investment Company Act. The Company is not and, after giving effect to the offering and sale of the Offered ADSs and the application of the proceeds thereof received by the Company as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, will not be required to register as an “investment company” or an entity “controlled” by an “investment company” within the meaning of the Investment Company Act of 1940, as amended, and the rules and regulations of the Commission thereunder and will not result in the Company being not in compliance with any applicable laws, rules and regulations with respect to the administration of foreign exchange or overseas investment in the PRC.

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(bb) Taxes. The Company and its subsidiaries have timely paid all taxes (except for cases in which the failure to pay would not have a Material Adverse Effect, or, except as currently being contested in good faith and for which reserves required by GAAP have been created in the financial statements of the Company) and timely filed all tax returns required to be paid or filed through the date hereof (except where the failure to file would not, individually or in the aggregate, have a Material Adverse Effect); and except as otherwise disclosed in each of the Registration Statement, the Pricing Disclosure Package and the Prospectus, the Company and its subsidiaries are not aware of any tax deficiency that has been, or is reasonably expected to be, asserted against the Company or any of its subsidiaries or any of their respective properties or assets (except for such tax deficiencies that would not, individually or in the aggregate, have a Material Adverse Effect). The Company is properly treated as a corporation for U.S. federal income tax purposes and has previously filed with the U.S. Internal Revenue Service a valid Form 8832, electing to be treated as a corporation for U.S. federal income tax purposes, and since that filing, the Company has not made any further filings on Form 8832 to be treated as other than a corporation for U.S. federal income tax purposes.

(cc) Licenses and Permits. The Company and its subsidiaries possess all licenses, sub-licenses, certificates, permits and other authorizations issued by, and have made all declarations and filings with, the appropriate federal, state, local or foreign governmental or regulatory authorities that are necessary for the ownership or lease of their respective properties or the conduct of their respective businesses as described in each of the Registration Statement, the Pricing Disclosure Package and the Prospectus, except where the failure to possess or make the same would not, individually or in the aggregate, have a Material Adverse Effect; and except as described in each of the Registration Statement, the Pricing Disclosure Package and the Prospectus, neither the Company nor any of its subsidiaries has received notice of any revocation or modification of any such license, sub-license, certificate, permit or authorization or has any reason to believe that any such license, sub-license, certificate, permit or authorization will not be renewed in the ordinary course, except where such revocation, modification or non-renewal would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect. Except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, the Company and its subsidiaries (i) are in compliance with all statutes, rules and regulations applicable to the ownership, testing, research, development, manufacture, packaging, labeling, processing, use, distribution, promotion, sale, pricing, storage, import, export or disposal of any product in development, manufactured, distributed, marketed, offered for sale or sold by the Company or its subsidiaries (“Applicable Laws”), except where such noncompliance would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; and (ii) have not received any U.S. Food and Drug Administration, China National Medical Products Administration (“NMPA”) (formerly China State Drug Administration (“SDA”)) notices or forms, written notice of adverse finding, warning letter, untitled letter or other correspondence or written notice from any court or arbitrator or governmental or regulatory authority alleging or asserting non-compliance with (x) any Applicable Laws or (y) any licenses, exemptions, certificates, approvals, clearances, authorizations, permits and supplements or amendments thereto required by any such Applicable Laws, except for such notices relating to non-compliance as would not have a Material Adverse Effect.

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(dd) No Labor Disputes; Compliance with Labor Laws. No labor disturbance by, or dispute with, employees of the Company or any of its subsidiaries exists or, to the knowledge of the Company, is contemplated or threatened. The Company is not aware of any existing or imminent labor disturbance or dispute between any of its or its subsidiaries’ principal suppliers, contractors or customers and the respective employees of such principal suppliers, contractors or customers, except as would not have a Material Adverse Effect. The Company and its subsidiaries are, and have been at all times, in compliance with all applicable labor laws and regulations, except as would not have a Material Adverse Effect. To the knowledge of the Company, no government investigation or proceedings with respect to labor law compliance exists, or, to the knowledge of the Company, is imminent.

(ee) Certain Environmental Matters. (i) The Company and its subsidiaries (x) are in compliance with all applicable federal, state, local and foreign laws (including common law), rules, regulations, requirements, decisions, judgments, decrees, orders and other legally enforceable requirements relating to pollution or the protection of human health or safety, the environment, natural resources, hazardous or toxic substances or wastes, pollutants or contaminants (collectively, “Environmental Laws”); (y) have received and are in compliance with all permits, licenses, certificates or other authorizations or approvals required of them under any Environmental Laws to conduct their respective businesses; and (z) have not received notice of any actual or potential liability or obligation under or relating to, or any actual or potential violation of, any Environmental Laws, including for the investigation or remediation of any disposal or release of hazardous or toxic substances or wastes, pollutants or contaminants, and have no knowledge of any event or condition that would reasonably be expected to result in any such notice, and (ii) there are no costs or liabilities associated with Environmental Laws of or relating to the Company or its subsidiaries, except in the case of each of (i) and (ii) above, for any such matter as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; and (iii) except as described in each of the Pricing Disclosure Package and the Prospectus, (x) there is no proceeding that is pending, or, to the Company’s knowledge, contemplated, against the Company or its subsidiaries under any Environmental Laws in which a governmental entity is also a party, other than such proceeding regarding which it is reasonably believed no monetary sanctions of $300,000 or more will be imposed, (y) the Company and its subsidiaries are not aware of any facts or issues regarding compliance with Environmental Laws, or liabilities or other obligations under Environmental Laws or concerning hazardous or toxic substances or wastes, pollutants or contaminants, that would reasonably be expected to have a material effect on the capital expenditures, earnings or competitive position of the Company and its subsidiaries, and (z) neither the Company nor its subsidiaries anticipates material capital expenditures relating to any Environmental Laws.

(ff) No Undisclosed Benefits. Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, (i) neither the Company nor any of its subsidiaries has a material obligation to provide health, retirement, death or disability benefits to any of the present or past employees or directors of the Company or its subsidiaries or to any other person, (ii) the Company and its subsidiaries are in material compliance with all applicable laws relating to employee benefits, and (iii) neither the Company nor any of its

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subsidiaries nor any ERISA Affiliate has any liability with regard to any health, retirement, death or disability benefit obligation of any affiliate, in each case except as would not be reasonably expected, individually or in the aggregate, to have a Material Adverse Effect. An “ERISA Affiliate” means any trade or business (whether or not incorporated) that, together with the Company, is treated as a single employer under Section 414(b) or (c) of the Internal Revenue Code of 1986, as amended (“Code”), is treated as under common control with the Company within the meaning of Section 4001(a)(14) of Employee Retirement Income Security Act of 1974 (“ERISA”) or, solely for purposes of Section 302 of ERISA and Section 412 of the Code, is treated as a single employer under Section 414 of the Code.

(gg) Disclosure Controls. The Company and its subsidiaries maintain an effective system of “disclosure controls and procedures” (as defined in Rule 13a-15(e) of the Exchange Act) that complies with the requirements of the Exchange Act and the Listing Rules and that has been designed to ensure that information required to be disclosed by the Company in reports that it files or submits under the Exchange Act or the Listing Rules, as applicable, is recorded, processed, summarized and reported within the time periods specified in the Commission’s rules and forms, including controls and procedures designed to ensure that such information is accumulated and communicated to the Company’s management as appropriate to allow timely decisions regarding required disclosure. The Company and its subsidiaries have carried out evaluations of the effectiveness of their disclosure controls and procedures as required by Rule 13a-15 of the Exchange Act.

(hh) Accounting Controls. The Company and its subsidiaries maintain systems of “internal control over financial reporting” (as defined in Rule 13a-15(f) of the Exchange Act) that comply with the requirements of the Exchange Act and have been designed by, or under the supervision of, their respective principal executive and principal financial officers, or persons performing similar functions, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with GAAP. The Company and its subsidiaries maintain internal accounting controls sufficient to provide reasonable assurance that (i) transactions are executed in accordance with management’s general or specific authorizations; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with GAAP and to maintain asset accountability; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; (iv) the recorded accountability for assets is compared with the existing assets at reasonable intervals and appropriate action is taken with respect to any differences and (v) the interactive data in eXtensible Business Reporting Language included or incorporated by reference in the Registration Statement, the Prospectus and the Pricing Disclosure Package fairly presents the information called for in all material respects and is prepared in accordance with the Commission’s rules and guidelines applicable thereto. Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, there are no material weaknesses in the Company’s internal controls. The Company’s auditors and the Audit Committee of the Board of Directors of the Company have been advised of: (i) all significant deficiencies and material weaknesses in the design or operation of internal controls over financial reporting which have adversely affected or are reasonably likely to adversely affect the Company’s ability to record, process, summarize and report financial information; and (ii) any fraud, whether or not material, that involves management or other employees who have a significant role in the Company’s internal controls over financial reporting.

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(ii) Insurance. The Company and its subsidiaries have insurance covering their respective properties, operations, personnel and businesses, which insurance is in amounts and insures against such losses and risks as the Company reasonably believes are adequate to protect the Company and its subsidiaries and their respective businesses taken as a whole; and neither the Company nor any of its subsidiaries has (i) received notice from any insurer or agent of such insurer that capital improvements or other expenditures are required or necessary to be made in order to continue such insurance or (ii) any reason to believe that it will not be able to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage at reasonable cost from similar insurers as may be necessary to continue its business, except as would not, individually or in the aggregate, have a Material Adverse Effect.

(jj) Cybersecurity; Data Protection. Except as would not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect, (i) the Company and its subsidiaries’ information technology assets and equipment, computers, systems, networks, hardware, software, websites, applications, and databases (collectively, “IT Systems”) are adequate for, and operate and perform as required in connection with the operation of the business of the Company and its subsidiaries as currently conducted; (ii) the Company and its subsidiaries have implemented and maintained commercially reasonable controls, policies, procedures, and safeguards to maintain and protect their confidential information and the integrity, continuous operation, redundancy and security of all IT Systems and data (including all personal, personally identifiable, health, sensitive, confidential or other regulated data, or any such data that may constitute trade secrets and working secrets of any governmental or regulatory authority in the PRC or any other data that would otherwise be detrimental to national security or public interest of the PRC pursuant to the applicable PRC laws (“Personal Data”)) used in connection with their businesses, and there have been no breaches, violations, outages, or unauthorized uses of or accesses to or same, except for those that have been remedied without material cost or liability or the duty to notify any other person, nor any incidents under internal review or investigations relating to the same; (iii) the Company and its subsidiaries are presently in compliance with all applicable laws (including, without limitation, the Provisions on Strengthening Confidentiality and Archives Administration of Overseas Securities Offering and Listing by Domestic Companies (关于加强境内企业境外发行证券和上市相关保密和档案管理工作的规定 ) issued by the CSRC, Ministry of Finance of the PRC, National Administration of State Secrets Protection of the PRC, and National Archives Administration of the PRC (effective from 31 March 2023), as amended, supplemented or otherwise modified from time to time) (the “CSRC Archive Rules”) or statutes and all judgments, orders, rules and regulations of any court or arbitrator or governmental or regulatory authority, internal policies and contractual obligations relating to the privacy and security, confidentiality and archive administration of IT Systems and Personal Data and to the protection of such IT Systems and Personal Data from unauthorized use, access, disclosure, misappropriation or modification; and (iv) neither the Company nor any of its subsidiaries is expected to be classified as a “critical information infrastructure operator” under the Cybersecurity Law of the PRC or subject to any investigation, inquiry or sanction relating to cybersecurity, data privacy, confidentiality or archive administration, or any cybersecurity review relating to cybersecurity, data privacy, confidentiality or archive administration, or any cybersecurity review of or relating to privacy and security, breaches, confidentiality and archive administration of IT Systems and Restricted Data or to the protection of such IT Systems and Restricted Data from unauthorized use, access, acquisition, disclosure, misappropriation or modification by the Cyberspace Administration of the PRC or any court or arbitrator or governmental or regulatory authority.

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(kk) No Unlawful Payments. Neither the Company nor its subsidiaries nor any director or officer of the Company or its subsidiaries nor, to the knowledge of the Company, any agent, employee, affiliate or other person associated with or acting on behalf of the Company or its subsidiaries has (i) used any corporate funds for any unlawful contribution, gift, entertainment or other unlawful expense relating to political activity; (ii) made or taken an act in furtherance of an offer, promise or authorization of any direct or indirect unlawful payment or benefit to any foreign or domestic government official or employee, including of any government-owned or controlled entity or of a public international organization, or any person acting in an official capacity for or on behalf of any of the foregoing, or any political party or party official or candidate for political office; (iii) violated or is in violation of any provision of the U.S. Foreign Corrupt Practices Act of 1977, as amended, or any applicable law or regulation implementing the OECD Convention on Combating Bribery of Foreign Public Officials in International Business Transactions, or committed an offence under the Bribery Act 2010 of the United Kingdom or any other applicable anti-bribery or anticorruption law (collectively, the “Anti-Corruption Laws”); or (iv) made, offered, agreed, requested or taken an act in furtherance of any unlawful bribe or other unlawful benefit, including, without limitation, any rebate, payoff, influence payment, kickback or other unlawful or improper payment or benefit. The Company and its subsidiaries have instituted, maintain and enforce, and will continue to maintain and enforce policies and procedures designed to promote and ensure compliance with the Anti-Corruption Laws. Neither the Company nor its subsidiaries will use, directly or indirectly, the proceeds of the offering in furtherance of an offer, payment, promise to pay, or authorization of the payment or giving of money, or anything else of value, to any person in violation of any Anti-Corruption Law.

(ll) Compliance with Anti-Money Laundering Laws. The operations of the Company and its subsidiaries are and have been conducted at all times in compliance with applicable financial recordkeeping and reporting requirements, including those of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the Anti-Money Laundering Law of the PRC (《中华人民共和国反洗钱法》), as amended and any other applicable money laundering statutes of all jurisdictions where the Company or any of its subsidiaries conducts business, the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any governmental agency (collectively, the “Anti-Money Laundering Laws”), and no action, suit or proceeding by or before any court or governmental agency, authority or body or any arbitrator involving the Company or any of its subsidiaries with respect to the Anti-Money Laundering Laws is pending or, to the knowledge of the Company, threatened.

(mm) No Conflicts with Sanctions Laws. Neither the Company nor its subsidiaries nor, to the knowledge of the Company, any director or officer of the Company or its subsidiaries, or any agent, employee, affiliate or other person associated with or acting on behalf of the Company or its subsidiaries is currently the subject or the target of any financial, economic, or trade sanctions or export controls administered or enforced by the U.S. government (including, without limitation, the Office of Foreign Assets Control of the U.S. Department of the Treasury, the U.S. Department of Commerce, the U.S. Department of State and including, without limitation, the designation as a “specially designated national” or “blocked person”), the

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United Nations Security Council, the European Union, His Majesty’s Treasury or other relevant sanctions authority (collectively, “Sanctions”), nor is the Company or its subsidiaries located, organized or resident in a country or territory that is the subject or target of Sanctions, including, without limitation, the so-called Donetsk People’s Republic and Luhansk People’s Republic, Zaporizhzhia, Kherson and Crimea regions of Ukraine, Cuba, Iran, North Korea, and Syria (each, a “Sanctioned Country”); and the Company will not directly or indirectly use the proceeds of the offering of the Shares hereunder, or lend, contribute or otherwise make available such proceeds to any subsidiaries, joint venture partner or other person or entity (i) to fund or facilitate any activities of or business with any person that, at the time of such funding or facilitation, is the subject or target of Sanctions, (ii) to fund or facilitate any activities of or business in any Sanctioned Country or (iii) in any other manner that will result in a violation by any person (including any person participating in the transaction, whether as underwriter, advisor, investor or otherwise) of Sanctions. For the past ten years, the Company and its subsidiaries have not knowingly engaged in and are not now knowingly engaged in any dealings or transactions with any person that at the time of the dealing or transaction is or was the subject or the target of Sanctions or with any Sanctioned Country.

(nn) No Restrictions on Subsidiaries. No subsidiary of the Company is currently prohibited, directly or indirectly, under any agreement or other instrument to which it is a party or is subject, from paying any dividends to the Company, from making any other distribution on such subsidiary’s capital stock or similar ownership interest, from repaying to the Company any loans or advances to such subsidiary from the Company or from transferring any of such subsidiary’s properties or assets to the Company or any other subsidiary of the Company.

(oo) No Broker’s Fees. Neither the Company nor any of its subsidiaries is a party to any contract, agreement or understanding with any person (other than this Agreement) that would give rise to a valid claim against any of them or any Underwriter for a brokerage commission, finder’s fee or like payment in connection with the offering and sale of the Offered ADSs.

(pp) No Registration Rights. Except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, no person has the right to require the Company or any of its subsidiaries to register any securities for sale under the Securities Act by reason of the filing of the Registration Statement with the Commission, the issuance and sale of the Offered ADSs other than have been validly waived by the Company.

(qq) No Stabilization. The Company has not taken, directly or indirectly (without giving any effect to the activities of the Underwriters), any action designed to or that would reasonably be expected to cause or result in any stabilization or manipulation of the price of the Offered ADSs.

(rr) Margin Rules. Neither the issuance, sale and delivery of the Offered ADSs nor the application of the proceeds received by the Company as described in each of the Registration Statement, the Pricing Disclosure Package and the Prospectus will violate Regulation T, U or X of the Board of Governors of the Federal Reserve System or any other regulation of such Board of Governors.

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(ss) Forward-Looking Statements. No forward-looking statement (within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act) included or incorporated by reference in any of the Registration Statement, the Pricing Disclosure Package, the Prospectus or any CSRC Filing (as defined in Section 3(qqq)) that has been filed with the CSRC on or prior to the date hereof has been made or reaffirmed, or in the case of any CSRC Filings to be filed with the CSRC after the Closing Date, will be made or reaffirmed, without a reasonable basis or has been disclosed other than in good faith.

(tt) Statistical and Market Data. Nothing has come to the attention of the Company that has caused the Company to believe that the statistical and market-related data included or incorporated by reference in each of the Registration Statement, the Pricing Disclosure Package and the Prospectus is not based on or derived from sources that are reliable and accurate in all material respects.

(uu) Sarbanes-Oxley Act. To the extent applicable to the Company and its directors and officers, there is and has been no failure on the part of the Company or, to the knowledge of the Company, any of the Company’s directors or officers, in their capacities as such, to comply with any provision of the Sarbanes-Oxley Act of 2002, as amended and the rules and regulations promulgated in connection therewith (the “Sarbanes-Oxley Act”), including Section 402 related to loans and Sections 302 and 906 related to certifications.

(vv) Status under the Securities Act. At the time of filing the Registration Statement and any post-effective amendment thereto, at the earliest time thereafter that the Company or any offering participant made a bona fide offer (within the meaning of Rule 164(h)(2) under the Securities Act) of the Shares and at the date hereof, the Company was not and is not an “ineligible issuer,” as defined in Rule 405 under the Securities Act.

(ww) No Rated Securities. There are no debt securities or preferred stock of, or guaranteed by, the Company that are rated by a “nationally recognized statistical rating organization,” as such term is defined by the Commission for the purposes of Section 3(a)(62) of the Exchange Act.

(xx) Clinical Trials. (i) Except as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, the clinical and pre-clinical trials conducted by or, to the knowledge of the Company, on behalf of or sponsored by the Company or its subsidiaries, taken as a whole, or in which the Company or its subsidiaries, taken as a whole, have participated and that are described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, or the results of which are referred to in the Registration Statement, the Pricing Disclosure Package and the Prospectus, as applicable, were, and if still pending are, being conducted in all material respects in accordance with standard medical and scientific research standards and procedures for products or product candidates comparable to those being developed by the Company and all applicable statutes and all applicable rules and regulations of the SDA, NMPA and comparable regulatory agencies outside of China to which they are subject (collectively, the “Regulatory Authorities”) and current Good Clinical Practices and Good Laboratory Practices; (ii) the descriptions in the Registration Statement, the Pricing Disclosure Package and the Prospectus of the results of such trials, studies and tests are accurate and complete descriptions in all material respects and fairly present the data derived therefrom; (iii)

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the Company has no knowledge of any other trials, studies or tests not described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, the results of which are inconsistent with or call into question the results described or referred to in the Registration Statement, the Pricing Disclosure Package and the Prospectus; (iv) the Company and its subsidiaries have operated at all times and are currently in compliance in all material respects with all applicable statutes, rules and regulations of the Regulatory Authorities; and (v) neither the Company nor any of its subsidiaries have received any written notices, correspondence or other communications from the Regulatory Authorities or any other governmental agency requiring or threatening the termination, material modification or suspension of any clinical or pre-clinical trials, studies or tests that are described in the Registration Statement, the Pricing Disclosure Package and the Prospectus or the results of which are referred to in the Registration Statement, the Pricing Disclosure Package and the Prospectus, other than ordinary course communications with respect to modifications in connection with the design and implementation of such trials, studies or tests, and, to the Company’s knowledge, there are no reasonable grounds for the same.

(yy) Regulatory Filings. The Company has not failed to file with the Regulatory Authorities any required filing, declaration, listing, registration, report or submission that is a responsibility of the Company with respect to the Company’s products or product candidates that are described or referred to in the Registration Statement, the Pricing Disclosure Package and the Prospectus; all such filings, declarations, listings, registrations, reports or submissions were in material compliance with applicable laws when filed; and no deficiencies regarding compliance with applicable law have been asserted by any applicable Regulatory Authority with respect to any such filings, declarations, listings, registrations, reports or submissions that would reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect.

(zz) Stamp, Transfer and Other Taxes. No stamp, issuance, capital, transfer, registration, value-added or other similar taxes are payable by or on behalf of the Underwriters in the Cayman Islands, Hong Kong, the PRC, the United States or any political subdivision or taxing authority thereof or therein solely in connection with (A) the issuance and delivery of Offered ADSs to the Underwriters in the manner contemplated by this Agreement, (B) the offer, sale and delivery by the Underwriters of the Offered ADSs or (C) the execution and delivery of this Agreement.

(aaa) No Immunity. Neither the Company nor any of its subsidiaries or their properties or assets has immunity under the laws of the Cayman Islands, Hong Kong and the PRC, U.S. federal or New York state law from any legal action, suit or proceeding, from the giving of any relief in any such legal action, suit or proceeding, from set-off or counterclaim, from the jurisdiction of Cayman Islands, Hong Kong and the PRC, U.S. federal or New York state court, from service of process, attachment upon or prior to judgment, or attachment in aid of execution of judgment, or from execution of a judgment, or other legal process or proceeding for the giving of any relief or for the enforcement of a judgment, in any such court with respect to their respective obligations, liabilities or any other matter under or arising out of or in connection herewith; and, to the extent that the Company or any of its subsidiaries or any of its properties, assets or revenues may have or may hereafter become entitled to any such right of immunity in any such court in which proceedings arising out of, or relating to the transactions contemplated by the Transaction Documents, may at any time be commenced, the Company has, pursuant to Section 18(d) of this Agreement, waived, and it will waive, or will cause its subsidiaries to waive, such right to the extent permitted by law.

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(bbb) Valid Choice of Law. The choice of the laws of the State of New York as the governing law of the Transaction Documents is a valid choice of law under the laws of the Cayman Islands and the PRC and will be honored by courts in the Cayman Islands and the PRC, subject to the conditions and restrictions described under the caption “Enforceability of certain civil liabilities” in the Registration Statement, the Pricing Disclosure Package and the Final Prospectus. The Company has the power to submit, and pursuant to Section 18(d) of this Agreement and Section 7.6 of the Deposit Agreement, has legally, validly, effectively and irrevocably submitted, to the personal jurisdiction of each New York State and United States Federal court sitting in The City of New York (each, a “New York Court”) and has validly and irrevocably waived any objection to the laying of venue of any suit, action or proceeding brought in such court; and the Company has the power to designate, appoint and authorize, and pursuant to Section 18(d) of this Agreement and Section 7.6 of the Deposit Agreement, has legally, validly, effectively and irrevocably designated, appointed and authorized, an agent for service of process in any action arising out of or relating to the Transaction Documents, the Registration Statement, the Pricing Disclosure Package, the Final Prospectus, the ADS Registration Statement or the offering of the Offered ADSs in any New York Court, and service of process in any manner permitted by applicable laws effected on such authorized agent will be effective to confer valid personal jurisdiction over the Company as provided hereof or in the Deposit Agreement.

(ccc) Merger or Consolidations. Neither the Company nor any of its subsidiaries has entered into any memorandum of understanding, letter of intent, definitive agreement or any similar agreements with respect to a merger or consolidation or a material acquisition or disposition of assets, technologies, business units or businesses.

(ddd) Termination of Contracts. Neither the Company nor its subsidiaries has sent or received any communication regarding early termination of, or intent not to renew, any of the material contracts or agreements referred to or described in the Registration Statement, the Pricing Disclosure Package and the Prospectus or filed as an exhibit to the Registration Statement to the extent that such contracts and agreements are of the kind that is typically renewable, and no such termination or non-renewal has been threatened by the Company or any of its subsidiaries or by any other party to any such contract or agreement.

(eee) Personal Liability of Shareholders and ADS holders. No holder of any of the Shares or the Offered ADSs after the consummation of the transactions contemplated by the Transaction Documents is or will be subject to any personal liability in respect of any liability of the Company or its subsidiaries by virtue only of its holding of any such Shares or Offered ADSs; and, except as set forth in the Registration Statement, the Pricing Disclosure Package and the Prospectus, there are no material limitations on the rights of holders of the Shares or the Offered ADSs who are not PRC residents to hold, vote or transfer their securities.

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(fff) Compliance with PRC Regulations on PRC Overseas Investment and Listing. Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, each of the Company and its subsidiaries that was incorporated outside of the PRC has complied with, and has taken all reasonable steps to comply with and to ensure compliance by each of its shareholders, option holders, directors, officers and employees that is, or is directly or indirectly owned or controlled by, a PRC resident or citizen with any applicable rules and regulations of the relevant PRC government agencies (including but not limited to the Ministry of Commerce, the National Development and Reform Commission and the State Administration of Foreign Exchange) relating to overseas investment by PRC residents and citizens (the “PRC Overseas Investment and Listing Regulations”), including, without limitation, requesting each shareholder, option holder, director, officer and employee that is, or is directly or indirectly owned or controlled by, a PRC resident or citizen to complete any registration and other procedures required under applicable PRC Overseas Investment and Listing Regulations.

(ggg) Compliance with Tax Exemption Laws and Regulations. Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, each of the Company’s subsidiaries operating in the PRC is in compliance in all material respects with all requirements under all applicable PRC laws and regulations to qualify for their income tax benefits, local, provincial and national PRC governmental tax holidays, relief, exemptions, concessions, waivers, preferential treatment and financial subsidies (the “Tax Benefits”), and the actual operations and business activities of the Company’s subsidiaries are sufficient to meet the qualifications for their Tax Benefits. No submissions made to any PRC government authority in connection with obtaining its Tax Benefits contained any misstatement or omission that would have affected the granting of its Tax Benefits. The Company’s subsidiaries in the PRC have not received notice of any deficiency in their respective applications for their Tax Benefits, and the Company is not aware of any reason why the subsidiaries in the PRC might not qualify for, or be in compliance with the requirements for, their Tax Benefits.

(hhh) Indemnification and Contribution. The indemnification and contribution provisions set forth in Section 9 hereof do not contravene Cayman Island, Hong Kong or PRC law or public policy.

(iii) Dividends. Except as disclosed in the Registration Statement, the Pricing Disclosure Package and the Prospectus, no approvals are currently required in the Cayman Islands in order for the Company to pay dividends or other distributions declared by the Company to the holders of Shares. Under current laws and regulations of the Cayman Islands and any political subdivision thereof, any amount payable with respect to the Shares upon liquidation of the Company or upon redemption thereof and dividends and other distributions declared and payable on the share capital of the Company may be paid by the Company in United States dollars or euros and freely transferred out of the Cayman Islands, and no such payments made to the holders thereof or therein who are non-residents of the Cayman Islands will be subject to income, withholding or other taxes under laws and regulations of the Cayman Islands or any political subdivision or taxing authority thereof or therein and without the necessity of obtaining any governmental authorization in the Cayman Islands or any political subdivision or taxing authority thereof or therein.

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(jjj) Legality. The legality, validity, enforceability or admissibility into evidence of any of the Registration Statement, the Pricing Disclosure Package, the Prospectus, this Agreement or the Offered ADSs in any jurisdiction in which the Company is organized or does business is not dependent upon such document being submitted into, filed or recorded with any court or other authority in any such jurisdiction on or before the date hereof or that any tax, imposition or charge be paid in any such jurisdiction on or in respect of any such document.

(kkk) Legal Action. A holder of the Offered ADSs and each Underwriter are each entitled to sue as plaintiff in the court of the jurisdiction of formation and domicile of the Company for the enforcement of their respective rights under this Agreement and the Offered ADSs and such access to such courts will not be subject to any conditions which are not applicable to residents of such jurisdiction or a company incorporated in such jurisdiction except that plaintiffs not residing in the Cayman Islands may be required to guarantee payment of a possible order for payment of costs or damages at the request of the defendant.

(lll) [Reserved.]

(mmm) Transaction Agreements under Cayman Law. Each of the Transaction Documents is in proper form to be enforceable against the Company in the Cayman Islands in accordance with its terms; to ensure the legality, validity, enforceability or admissibility into evidence in the Cayman Islands of any Transaction Document, it is not necessary that such Transaction Document be filed or recorded with any court or other authority in the Cayman Islands (other than court filings in the normal course of proceedings) or that any stamp or similar tax (other than nominal stamp duty if such Transaction Document is executed in or brought into the Cayman Islands) in the Cayman Islands be paid on or in respect of such Transaction Document or any other documents to be furnished hereunder.

(nnn) eXtensible Business Reporting Language. The interactive data in eXtensible Business Reporting Language included or incorporated by reference in the Registration Statement fairly presents the information called for in all material respects and has been prepared in accordance with the Commission’s rules and guidelines applicable thereto.

(ooo) Testing-the-Waters Communications. The Company (i) has not alone engaged in any Testing-the-Waters Communication and (ii) has not authorized anyone other than the Representatives to engage in Testing-the-Waters Communications. The Company has not distributed any Written Testing-the-Waters Communications. “Testing-the-Waters Communication” means any oral or written communication with potential investors undertaken in reliance on Rule 163B of the Securities Act. “Written Testing-the-Waters Communication” means any Testing-the-Waters Communication that is a written communication within the meaning of Rule 405.

(ppp) No Prohibitions Against Overseas Offerings. The Company is not, and will not be (until the later of the Closing Date or the Additional Closing Date, as the case may be), prohibited from conducting securities offerings outside the PRC under Article 8 of the Trial Administrative Measures of Overseas Securities Offering and Listing by Domestic Companies (境内企业境外发行证券和上市管理试行办法) and supporting guidelines issued by the CSRC (effective from 31 March 2023), as amended, supplemented or otherwise modified from time to time (“CSRC Filing Rules,” together with the CSRC Archive Rules, the “CSRC Rules”) or other applicable laws and regulations of the PRC.

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(qqq) Accuracy and Adequacy of CSRC Filings. Each letter, filing, correspondence, communication, document, response, undertaking and submission in any form, including any amendments, supplements and/or modifications thereof, made or to be made to the CSRC, relating to or in connection with the offering of the Offered ADSs pursuant to the CSRC Filing Rules and other applicable rules and requirements of the CSRC (including, without limitation, the filing report of the Company in relation to the offering of the Offered ADSs, including any amendments, supplements and/or modifications thereof, to be submitted to the CSRC no later than three business days following the Closing Date pursuant to Article 13 of the CSRC Filing Rules (the “CSRC Filing Report”)) (a “CSRC Filing” and such date on which a CSRC Filing is required to be filed with the CSRC, a “CSRC Filing Date”) is and remains, and on each applicable CSRC Filing Date, will be, complete, true and accurate and not misleading in any respect, and does not, and will not on each applicable CSRC Filing Date, omit any information which would make the statements made therein, misleading in any respect, and does not contain any conflicting, inconsistent or materially different descriptions of facts.

(rrr) Submission of CSRC Filings. The Company has complied with, and on each applicable CSRC Filing Date will remain in compliance with, all applicable requirements, and will timely submit by each applicable CSRC Filing Date, all requisite filings in connection with the offering of the Offered ADSs (including, without limitation, the CSRC Filing Report) with the CSRC pursuant to the CSRC Filing Rules and all applicable laws, and the Company has not received any notice of rejection, withdrawal or revocation from the CSRC in connection with such CSRC Filings.

(sss) Compliance with CSRC Filing Rules. The Registration Statement, the Pricing Disclosure Package, the Prospectus and each CSRC Filing made by or on behalf of the Company is, and on each CSRC Filing Date, all other documents filed with the CSRC, or issued by or on behalf of the Company in connection with the offering of the Offered ADSs, are and will be, in compliance with the disclosure requirements pursuant to the CSRC Filing Rules and do not contain any statement or commentary in violation of Article 20 of the CSRC Filing Rules. Each CSRC Filing contains detailed analysis on the fulfilment of Article 15 of the CSRC Filing Rules and descriptions of all material events as required to be reported pursuant to the CSRC Filing Rules or other applicable laws, regulations and rules in the PRC.

(ttt) No Covered Activities. The Company does not currently engage in, has no current intention of engaging in, and shall not engage in the design, fabrication, development, testing, production, manufacture, installation, sale or packaging of one or more “covered national security technologies and products” (including, but not limited to, semiconductors and microelectronics, quantum information technologies, or artificial intelligence systems) within the meaning of Executive Order 14105 of August 9, 2023, including all implementing regulations thereof, codified at 31 C.F.R. Part 850, et seq.

(uuu) No Covered Foreign Person. The Company is not and shall not become a “covered foreign person” within the meaning of Executive Order 14105 of August 9, 2023, including all implementing regulations thereof, codified at 31 C.F.R. Part 850, et seq.

4. [Reserved.]

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5. Further Agreements of the Company. The Company covenants and agrees with each Underwriter that:

(a) Required Filings. The Company will file the final Prospectus with the Commission within the time periods specified by Rule 424(b) and Rule 430A, 430B or 430C under the Securities Act, will file any Issuer Free Writing Prospectus to the extent required by Rule 433 under the Securities Act; and the Company will file promptly all reports and any definitive proxy or information statements required to be filed by the Company with the Commission pursuant to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act subsequent to the date of the Prospectus and for so long as the delivery of a prospectus is required in connection with the offering or sale of the Shares; the Company will furnish copies of the Prospectus and each Issuer Free Writing Prospectus (to the extent not previously delivered) to the Underwriters in New York City prior to 10:00 A.M., New York City time, on the business day next succeeding the date of this Agreement in such quantities as the Representatives may reasonably request. The Company will pay the registration fee for this offering within the time period required by Rule 456(b)(1) under the Securities Act (without giving effect to the proviso therein) and in any event prior to the Closing Date. The Company will file each CSRC Filing with the CSRC within the time periods specified by the CSRC Filing Rules, and in any event no later than the applicable CSRC Filing Date (which for the avoidance of doubt, shall be three business days after the Closing Date as it relates to the CSRC Filing Report); and the Company will use its best efforts to procure the acceptance of each of such CSRC Filing by the CSRC.

(b) Delivery of Copies. The Company will deliver, without charge, (i) to the Representatives, upon its reasonable request, conformed (or, if specifically requested, two signed) copies of the Registration Statement as originally filed and each amendment thereto, in each case including all exhibits and consents filed therewith and documents incorporated by reference therein; and (ii) to each Underwriter, upon their reasonable request, (A) a conformed copy of the Registration Statement as originally filed and each amendment thereto (without exhibits) and (B) during the Prospectus Delivery Period (as defined below), as many copies of the Prospectus (including all amendments and supplements thereto and documents incorporated by reference therein and each Issuer Free Writing Prospectus) as the Representatives may reasonably request. As used herein, the term “Prospectus Delivery Period” means such period of time after the first date of the public offering of the Offered ADSs as in the opinion of counsel for the Underwriters a prospectus relating to the Offered ADSs is required by law to be delivered (or required to be delivered but for Rule 172 under the Securities Act) in connection with sales of the Offered ADSs by any Underwriter or dealer.

(c) Delivery of CSRC Filing Documents. The Company will deliver, without charge, on the same day of each CSRC Filing, to the Underwriters, a copy of the PRC opinion addressed to the Company issued by Fangda Partners, dated as of the date of the applicable CSRC Filing, in the form and substance required under the Guideline No. 2 to the CSRC Filings Rules.

(d) Amendments or Supplements; Issuer Free Writing Prospectuses. Before making, preparing, using, authorizing, approving, referring to or filing any Issuer Free Writing Prospectus, and before filing any amendment or supplement to the Registration Statement, the Pricing Disclosure Package, the Prospectus or any CSRC Filing, the Company will furnish to the Representatives and counsel for the Underwriters a copy of the proposed Issuer Free Writing Prospectus, amendment or supplement for review and will not make, prepare, use, authorize, approve, refer to or file any such Issuer Free Writing Prospectus or file any such proposed amendment or supplement to which the Representatives reasonably object.

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(e) Notice to the Representatives. The Company will advise the Representatives promptly, and confirm such advice in writing, (i) when the Registration Statement has become effective; (ii) when any amendment to the Registration Statement has been filed or becomes effective; (iii) when any supplement to the Pricing Disclosure Package, the Prospectus, any Issuer Free Writing Prospectus or any amendment to the Prospectus has been filed or distributed; (iv) of any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Prospectus or the receipt of any comments from the Commission relating to the Registration Statement or any other request by the Commission for any additional information; (v) of the issuance by the Commission or any other governmental or regulatory authority of any order suspending the effectiveness of the Registration Statement or preventing or suspending the use of any Preliminary Prospectus, any of the Pricing Disclosure Package, the Prospectus or the initiation or threatening of any proceeding for that purpose or pursuant to Section 8A of the Securities Act; (vi) of the occurrence of any event or development within the Prospectus Delivery Period as a result of which the Prospectus, any of the Pricing Disclosure Package or any Issuer Free Writing Prospectus as then amended or supplemented would include any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances existing when the Prospectus, the Pricing Disclosure Package or any such Issuer Free Writing Prospectus is delivered to a purchaser, not misleading; and (vii) of the receipt by the Company of any notice of objection of the Commission to the use of the Registration Statement or any post-effective amendment thereto pursuant to Rule 401(g)(2) under the Securities Act; and (viii) of the receipt by the Company of any notice with respect to any suspension of the qualification of the Offered ADSs for offer and sale in any jurisdiction or, to the knowledge of the Company, the initiation or threatening of any proceeding for such purpose; and the Company will use its reasonable best efforts to prevent the issuance of any such order suspending the effectiveness of the Registration Statement, preventing or suspending the use of any Preliminary Prospectus, any of the Pricing Disclosure Package or the Prospectus or suspending any such qualification of the Offered ADSs and, if any such order is issued, will use its reasonable best efforts to obtain as soon as possible the withdrawal thereof. The Company will also advise the Representatives (for itself and on behalf of the Underwriters) promptly, and confirm such advice in writing, (i) where it becomes necessary at any time to amend or supplement any CSRC Filing; or (ii) when any material change to the information previously given to the CSRC occurs. Furthermore, the Company will furnish to the Representatives (for themselves and on behalf of the Underwriters) such information to enable the Representatives (for themselves and on behalf of the Underwriters) to provide (or procure their provision) to the CSRC, in a timely manner, such information as the CSRC, may require.

(f) Assistance to the Underwriters. The Company will give every assistance, and will use its best efforts to cause its subsidiaries, associates, substantial shareholders, and/or any of their respective directors, officers, employees, affiliates, agents, advisers, reporting accountants, auditors, legal counsels and other relevant parties engaged by the Company in connection with the offering of the Offered ADS, to give every assistance, to each of the Underwriters to meet its respective obligations and responsibilities to provide materials, information and documents to the CSRC under the CSRC Rules in connection with the transactions contemplated hereby.

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(g) Ongoing Compliance. (1) If during the Prospectus Delivery Period (i) any event or development shall occur or condition shall exist as a result of which the Prospectus as then amended or supplemented would include any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances existing when the Prospectus is delivered to a purchaser, not misleading or (ii) it is necessary to amend or supplement the Prospectus to comply with law, the Company will as soon as possible notify the Underwriters thereof and forthwith prepare and, subject to paragraph (c) above, file with the Commission and furnish to the Underwriters and to such dealers as the Representatives may designate such amendments or supplements to the Prospectus or any document to be filed with the Commission and incorporated by reference therein as may be necessary so that the statements in the Prospectus as so amended or supplemented or any document to be filed with the Commission and incorporated by reference therein will not, in the light of the circumstances existing when the Prospectus is delivered to a purchaser, be misleading or so that the Prospectus will comply with law and (2) if at any time prior to the Closing Date (i) any event or development shall occur or condition shall exist as a result of which the Pricing Disclosure Package as then amended or supplemented would include any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements therein, in the light of the circumstances existing when the Pricing Disclosure Package is delivered to a purchaser, not misleading or (ii) it is necessary to amend or supplement the Pricing Disclosure Package to comply with law, the Company will as soon as possible notify the Underwriters thereof and forthwith prepare and, subject to paragraph (c) above, file with the Commission (to the extent required) and furnish to the Underwriters and to such dealers as the Representatives may designate such amendments or supplements to the Pricing Disclosure Package or any document to be filed with the Commission and incorporated by reference therein as may be necessary so that the statements in the Pricing Disclosure Package as so amended or supplemented will not, in the light of the circumstances existing when the Pricing Disclosure Package is delivered to a purchaser, be misleading or so that the Pricing Disclosure Package will comply with law.

(h) Compliance with Cybersecurity; Data Protection. Except as would not reasonably be expected, individually or in the aggregate, to have a Material Adverse Effect, the Company will comply with all applicable laws and regulations in the PRC concerning cybersecurity, data protection, confidentiality and archive administrations (including, without limitation, the CSRC Archive Rules) in connection with (A) the establishment and maintenance of adequate and effective internal control measures and internal systems for maintenance of data protection, confidentiality and archive administration; (B) the relevant requirements and approval and filing procedures in connection with its handling, disclosure, transfer and retention of transfer of state secrets and working secrets of government agencies or any other documents or materials that would otherwise be detrimental to national security or public interest (the “Relevant Information”); and (C) maintenance of confidentiality of any Relevant Information; and where there is any material information required to be reported to the CSRC pursuant to the applicable laws (including, without limitation, the CSRC Rules), promptly notify the CSRC or the relevant PRC governmental authority and provide it with such material information in accordance with the applicable laws, and promptly notify the Representatives (for themselves and on behalf of the Underwriters) of such material information to the extent permitted by the applicable laws.

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(i) Blue Sky Compliance. The Company will qualify the Offered ADSs for offer and sale under the securities or Blue Sky laws of such jurisdictions as the Representatives shall reasonably request and will continue such qualifications in effect so long as required for distribution of the Offered ADSs; provided, that the Company shall not be required to (i) qualify as a foreign corporation or other entity or as a dealer in securities in any such jurisdiction where it would not otherwise be required to so qualify, (ii) file any general consent to service of process in any such jurisdiction or (iii) subject itself to taxation in any such jurisdiction if it is not otherwise so subject.

(j) Earning Statement. The Company will make generally available to its security holders and the Representatives as soon as reasonably practicable an earning statement that satisfies the provisions of Section 11(a) of the Securities Act and Rule 158 of the Commission promulgated thereunder covering a period of at least twelve months beginning with the first fiscal quarter of the Company occurring after the “effective date” (as defined in Rule 158) of the Registration Statement.

(k) Clear Market. For a period commencing on the date hereof and ending 90 days after the date of the Prospectus, the Company will not (i) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, or otherwise transfer or dispose of, directly or indirectly, or file with the Commission a registration statement under the Securities Act relating to, any Ordinary Shares or ADSs or any securities convertible into or exercisable or exchangeable for Ordinary Shares or ADSs, or publicly disclose the intention to make any offer, sale, pledge, disposition or filing, or (ii) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the Ordinary Shares or ADSs or any such other securities, whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of Ordinary Shares or ADSs or such other securities, in cash or otherwise, without the prior written consent of Goldman Sachs (Asia) L.L.C. and Jefferies LLC, other than (A) the Offered ADSs to be sold hereunder, (B) any Ordinary Shares or ADSs of the Company issued upon the exercise of options granted under Company Stock Plans, (C) any options and other awards granted under the Company Stock Plans, (D) the issuance by the Company of securities convertible into or exercisable or exchangeable for Ordinary Shares in connection with the hiring of new employees; provided, that such securities cannot be so converted, exercised or exchanged within the 90-day restricted period, (E) any Ordinary Shares issued pursuant to the conversion or exchange of convertible or exchangeable securities, including preferred shares and warrants, as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus, (F) the filing of any registration statement on Form S-8 relating to any benefit plans or arrangements disclosed in the Registration Statement, the Pricing Disclosure Package or the Prospectus and the issuance of securities registered pursuant thereto, or (G) any Ordinary Shares or securities exercisable for, convertible into or exchangeable for Ordinary Shares in connection with any acquisition, collaboration, licensing or other joint venture or strategic transaction or any debt financing transaction involving the Company; provided, that, in the case of clauses (B), (C), (E) and (G), (x) such issuances shall not in the aggregate be greater than 10% of the total outstanding Ordinary Shares of the Company immediately following the completion of this offering of ADSs which, for the avoidance of doubt, includes the Ordinary Shares issuable upon the conversion of preferred shares in connection with this offering, and (y) the recipients of such shares agree to be bound by a lockup letter in the form executed by directors and officers.

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(l) Use of Proceeds. The Company will apply the net proceeds from the sale of the ADSs as described in the Registration Statement, the Pricing Disclosure Package and the Prospectus under the heading “Use of proceeds.”

(m) No Stabilization. The Company will not take, directly or indirectly, any action designed to or that would reasonably be expected to cause or result in any stabilization or manipulation of the price of the Offered ADSs (it being understood that the Company makes no statement as to the activities of the Underwriters in connection with the offering).

(n) Exchange Listing. The Company will use its reasonable best efforts to maintain the listing of the ADSs on the Nasdaq Exchange.

(o) Reports. During a period of three years from the date hereof, the Company will furnish to the Representatives, as soon as they are available, copies of all reports or other communications (financial or other) furnished to holders of the Shares or ADSs, and copies of any reports and financial statements furnished to or filed with the Commission or any national securities exchange or automatic quotation system; provided the Company will be deemed to have furnished such reports and financial statements to the Representatives to the extent they are filed on either: (i) the Commission’s Electronic Data Gathering, Analysis, and Retrieval system or any successor system; or (ii) the HK Exchange’s HKEXnews or any successor system or public platform.

(p) Record Retention. The Company will, pursuant to reasonable procedures developed in good faith, retain copies of each Issuer Free Writing Prospectus that is not filed with the Commission in accordance with Rule 433 under the Securities Act.

(q) Shelf Renewal. If immediately prior to the third anniversary (the “Renewal Deadline”) of the initial effective date of the Registration Statement, any of the Offered ADSs remain unsold by the Underwriters, the Company will, prior to the Renewal Deadline, file, if it has not already done so and is eligible to do so, a new automatic shelf registration statement relating to the Offered ADSs, in a form satisfactory to the Representatives. If the Company is not eligible to file an automatic shelf registration statement, the Company will, prior to the Renewal Deadline, if it has not already done so, file a new shelf registration statement relating to the Offered ADSs, in a form satisfactory to the Representatives, and will use its best efforts to cause such registration statement to be declared effective within 180 days after the Renewal Deadline. The Company will take all other action necessary or appropriate to permit the issuance and sale of the Offered ADSs to continue as contemplated in the expired registration statement relating to the Offered ADSs. References herein to the Registration Statement shall include such new automatic shelf registration statement or such new shelf registration statement, as the case may be.

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(r) Filings. The Company will file with the Commission such reports as may be required by Rule 463 under the Securities Act.

(s) Tax Indemnity. The Company will indemnify and hold harmless the Underwriters against any documentary, stamp, issue, capital, registration or other similar tax, including any interest and penalties, on the sale of the Offered ADSs to, and the resale of the Offered ADSs by the Underwriters and on the execution and delivery of this Agreement. All payments to be made by the Company under this Agreement shall be made without withholding or deduction for or on account of any present or future taxes, duties or governmental charges whatsoever, unless the Company is compelled by law to deduct or withhold such taxes, duties or charges. In that event, the Company shall pay such additional amounts as may be necessary in order to ensure that the net amounts received after such withholding or deductions shall equal the amounts that would have been received if no withholding or deduction had been made, except to the extent such taxes, duties, or governmental charges (a) are net income taxes or franchise taxes payable by the Underwriters or (b)(i) are imposed or levied by reason of an Underwriter’s being connected with such taxing jurisdiction other than by reason of its being an Underwriter (or controlling person of such Underwriter) under this Agreement or (ii) would not have been imposed but for the failure to comply, upon request, with any certification, identification or other reporting requirements concerning the nationality, residence or identity of the Underwriter (or controlling person of such Underwriter), if such compliance is required as a precondition to exemption from, or reduction in the rate of, deduction or withholding of such taxes, provided, that such compliance would not be unreasonably onerous in the reasonable judgment of the relevant Underwriter or the person controlling such Underwriter.

6. [Reserved.]

7. Certain Agreements of the Underwriters. Each Underwriter hereby severally represents and agrees that:

(a) It has not used, authorized use of, referred to or participated in the planning for use of, and will not use, authorize use of, refer to or participate in the planning for use of, any “free writing prospectus,” as defined in Rule 405 under the Securities Act (which term includes use of any written information furnished to the Commission by the Company and not incorporated by reference into the Registration Statement and any press release issued by the Company) other than (i) a free writing prospectus that contains no “issuer information” (as defined in Rule 433(h)(2) under the Securities Act) that was not included (including through incorporation by reference) in the Preliminary Prospectus or a previously filed Issuer Free Writing Prospectus, (ii) any Issuer Free Writing Prospectus listed on Annex A or prepared pursuant to Section 3(c) or Section 5(c) above (including any electronic road show approved by the Company), (iii) any free writing prospectus prepared by such underwriter and approved by the Company in advance in writing or (iv) any free writing prospectus that is required to be used.

(b) It has not and will not, without the prior written consent of the Company, use any free writing prospectus that contains the final terms of the Offered ADSs unless such terms have previously been included in a free writing prospectus filed with the Commission; provided, that Underwriters may use a term sheet substantially in the form of Annex B hereto without the consent of the Company; provided, further that any Underwriter using such term sheet shall notify the Company, and provide a copy of such term sheet to the Company, prior to, or substantially concurrently with, the first use of such term sheet.

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(c) It is not subject to any pending proceeding under Section 8A of the Securities Act with respect to the offering (and will promptly notify the Company if any such proceeding against it is initiated during the Prospectus Delivery Period).

8. Conditions of Underwriters’ Obligations. The obligation of each Underwriter to purchase the Underwritten ADSs on the Closing Date or the Option ADSs on the Additional Closing Date, as the case may be, as provided herein is subject to the performance by the Company of its respective covenants and other obligations hereunder and to the following additional conditions:

(a) Registration Compliance; No Stop Order. No order suspending the effectiveness of the Registration Statement shall be in effect, and no proceeding for such purpose, pursuant to Rule 401(g)(2) or pursuant to Section 8A under the Securities Act shall be pending before or, to the knowledge of the Company, threatened by the Commission; the Prospectus and each Issuer Free Writing Prospectus shall have been timely filed with the Commission under the Securities Act (in the case of an Issuer Free Writing Prospectus, to the extent required by Rule 433 under the Securities Act) and in accordance with Section 5(a) hereof; and all requests by the Commission for additional information shall have been complied with to the reasonable satisfaction of the Representatives.

(b) Representations and Warranties. The respective representations and warranties of the Company contained herein shall be true and correct on the date hereof and on and as of the Closing Date or the Additional Closing Date, as the case may be; and the statements of the Company and its officers made in any certificates delivered pursuant to this Agreement shall be true and correct on and as of the Closing Date or the Additional Closing Date, as the case may be.

(c) [Reserved.]

(d) No Material Adverse Change. No event or condition of a type described in Section 3(j) hereof shall have occurred or shall exist, which event or condition is not described in the Pricing Disclosure Package (excluding any amendment or supplement thereto) and the Prospectus (excluding any amendment or supplement thereto) and the effect of which in the judgment of the Representatives makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Offered ADSs on the Closing Date or the Additional Closing Date, as the case may be, on the terms and in the manner contemplated by this Agreement, the Pricing Disclosure Package and the Prospectus.

(e) Officer’s Certificate. The Representatives shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, a certificate on behalf of the Company of the chief financial officer, vice president of finance or chief accounting officer of the Company and one additional senior executive officer of the Company who is reasonably satisfactory to the Representatives (i) confirming that such officers have carefully reviewed the Registration Statement, the Pricing Disclosure Package and the Prospectus and, to the knowledge

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of such officers, the representations of the Company set forth in Sections 3(b) hereof are true and correct, (ii) confirming that the other representations and warranties of the Company in this Agreement are true and correct and that the Company has complied, in all material respects, with all agreements and satisfied all conditions on its part to be performed or satisfied hereunder at or prior to the Closing Date or the Additional Closing Date, as the case may be, and (iii) to the effect set forth in paragraphs (a) and (d) above.

(f) Comfort Letters. (i) On the date of this Agreement and on the Closing Date or the Additional Closing Date, as the case may be, each of Deloitte Touche Tohmatsu Certified Public Accountants LLP and KPMG LLP shall have furnished to the Representatives, at the request of the Company, letters, dated the respective dates of delivery thereof and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representatives, containing statements and information of the type customarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information contained or incorporated by reference in the Registration Statement, the Pricing Disclosure Package and the Prospectus; provided, that the letter delivered by KPMG LLP on the Closing Date or the Additional Closing Date, as the case may be, shall use a “cut-off” date no more than three business days prior to such Closing Date or such Additional Closing Date, as the case may be.

(g) Opinion and 10b-5 Statement of Counsel for the Company. Ropes & Gray LLP, counsel for the Company, shall have furnished to the Representatives, at the request of the Company, their written opinion and 10b-5 statement, dated the Closing Date or the Additional Closing Date, as the case may be, and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representatives.

(h) Opinion of Cayman Islands Counsel for the Company. Travers Thorp Alberga, Cayman Islands counsel for the Company, shall have furnished to the Representatives, at the request of the Company, their written opinion, dated the Closing Date or the Additional Closing Date, as the case may be, and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representatives.

(i) Opinion of PRC Counsel for the Company. Fangda Partners, PRC counsel for the Company, shall have furnished to the Representatives, at the request of the Company, their written opinion, dated the Closing Date or the Additional Closing Date, as the case may be, and addressed to the Company, in form and substance reasonably satisfactory to the Representatives.

(j) [Reserved.]

(k) Opinion and 10b-5 Statement of Intellectual Property Counsel for the Company. The Representatives shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, (i) the written opinion of Fish & Richardson P.C., intellectual property counsel for the Company, in form and substance reasonably satisfactory to the Representatives, (ii) the written opinion and a 10b-5 statement from Ropes & Gray LLP, intellectual property counsel for the Company, in form and substance reasonably satisfactory to the Representatives, (iii) the written opinion and a 10b-5 statement from JunHe LLP, intellectual property counsel for the Company, in form and substance reasonably satisfactory to the Representatives, and (iv) the written opinion and a 10b-5 statement from Caihe Law Firm, intellectual property counsel for the Company, in form and substance reasonably satisfactory to the Representatives.

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(l) Intellectual Property Officer’s Certificate. The Representatives shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, a certificate on behalf of the Company of the senior vice president or other executive officer of the Company who is reasonably satisfactory to the Representatives confirming certain intellectual property matters, in form and substance reasonably satisfactory to the Representatives.

(m) Opinion and 10b-5 Statement of Counsel for the Underwriters. The Representatives shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, an opinion and 10b-5 statement, addressed to the Underwriters, of Simpson Thacher & Bartlett LLP, counsel for the Underwriters, with respect to such matters as the Representatives may reasonably request, and such counsel shall have received such documents and information as they may reasonably request to enable them to pass upon such matters.

(n) Opinion of PRC Counsel for the Underwriters. (i) The Representatives shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, an opinion of Commerce & Finance Law Offices, PRC counsel for the Underwriters, with respect to such matters as the Representatives may reasonably request, and such counsel shall have received such documents and information as they may reasonably request to enable them to pass upon such matters. (ii) The Representatives shall have received on and as of the same day of each CSRC Filing (A) a copy of the PRC opinion addressed to the Underwriters issued by Commerce & Finance Offices, dated as of the date of the applicable CSRC Filing, in the same form and substance as the PRC opinion issued by Fangda Partners required under the Guideline No. 2 to the CSRC Filings Rules and (B) a disclosure assurance letter/memorandum addressed to the Underwriters issued by Commerce & Finance Offices, dated as of the date of the applicable CSRC Filing, in relation to the truthfulness, accuracy and completeness of information contained in the applicable CSRC Filing Report.

(o) Opinion of Counsel for the Depositary. The Representatives shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, an opinion of Patterson Belknap Webb & Tyler LLP, counsel for the Depositary, with respect to such matters as the Representatives may reasonably request and in form and substance reasonably satisfactory to the Representatives.

(p) Opinion of Hong Kong Counsel for the Company. Sidley Austin LLP, Hong Kong counsel for the Company, shall have furnished to the Representatives, at the request of the Company, their written opinion, dated the Closing Date or the Additional Closing Date, as the case may be, and addressed to the Underwriters, in form and substance reasonably satisfactory to the Representatives.

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(q) No Legal Impediment to Issuance and/or Sale. No action shall have been taken and no statute, rule, regulation or order shall have been enacted, adopted or issued by any federal, state or foreign governmental or regulatory authority that would, as of the Closing Date or the Additional Closing Date, as the case may be, prevent the issuance or sale of the Offered ADSs by the Company; and no injunction or order of any domestic or foreign court shall have been issued that would, as of the Closing Date or the Additional Closing Date, as the case may be, prevent the issuance or sale of the Offered ADSs by the Company.

(r) Good Standing. The Representatives shall have received on and as of the Closing Date or the Additional Closing Date, as the case may be, satisfactory evidence of the good standing of the Company and its material subsidiaries in their respective jurisdictions of organization and their good standing in such other jurisdictions as the Representatives may reasonably request, in each case in writing or any standard form of telecommunication from the appropriate governmental authorities of such jurisdictions.

(s) Exchange Listing. The Offered ADSs to be delivered on the Closing Date or Additional Closing Date, as the case may be, shall have been duly listed on the Nasdaq Exchange.

(t) Listing Approval. The approval of the Listing Committee of HK Exchange for the listing of, and permission to deal in, the Underwritten Shares to be issued pursuant to the sale of the Offered ADSs (including the Option Shares which may be issued upon the exercise of the option in respect of the Option ADSs) shall have been granted (other than subject to customary conditions) on or before the Closing Date, and such approval has not been subsequently withdrawn, cancelled, qualified (other than by customary conditions), revoked or withheld before the Closing Date or Additional Closing Date (as applicable for closing the sale of the relevant Offered ADSs).

(u) Lock-up Agreements. The “lock-up” agreements, each substantially in the form of Exhibit B hereto, between you and officers and directors of the Company relating to sales and certain other dispositions of Ordinary Shares, ADSs or certain other securities, delivered to you on or before the date hereof, shall be in full force and effect on the Closing Date or Additional Closing Date, as the case may be.

(v) ADS Certificates at Closing Date. The Depositary shall have furnished or caused to be furnished to the Representatives at the Closing Date or Additional Closing Date, as the case may be, certificates satisfactory to the Representatives evidencing the deposit with it or its nominee of the Shares being so deposited against issuance of the Offered ADSs to be delivered by the Company at the Closing Date or Additional Closing Date, as the case may be, and the execution, countersignature (if applicable), issuance and delivery of such Offered ADSs pursuant to the Deposit Agreement.

(w) Additional Documents. On or prior to the Closing Date or the Additional Closing Date, as the case may be, the Company shall have furnished to the Representatives such further certificates and documents as the Representatives may reasonably request.

All opinions, letters, certificates and evidence mentioned above or elsewhere in this Agreement shall be deemed to be in compliance with the provisions hereof only if they are in form and substance reasonably satisfactory to counsel for the Underwriters.

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9. Indemnification and Contribution.

(a) Indemnification of the Underwriters by the Company. The Company agrees to indemnify and hold harmless each Underwriter, its affiliates, selling agents, directors, officers and employees, and the directors, officers and employees of the affiliates of each Underwriter, and each person, if any, who controls such Underwriter within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act, from and against any and all losses, claims, damages and liabilities (including, without limitation, reasonably incurred legal fees and other reasonably incurred expenses incurred in connection with any suit, action or proceeding or any claim asserted, as such fees and expenses are incurred), joint or several, that arise out of, or are based upon, (i) any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement or caused by any omission or alleged omission to state therein a material fact required to be stated therein or necessary in order to make the statements therein, not misleading; (ii) any untrue statement or alleged untrue statement of a material fact contained in the Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus, any “issuer information” filed or required to be filed pursuant to Rule 433(d) under the Securities Act, any road show as defined in Rule 433(h) under the Securities Act (a “road show”) or any Pricing Disclosure Package (including any Pricing Disclosure Package that has subsequently been amended), or caused by any omission or alleged omission to state therein a material fact necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading; (iii) any statement being, or alleged to be, untrue, incorrect, inaccurate, misleading or incomplete in any respect, contained in any CSRC Filing, or any amendments or supplements thereto (in each case, whether or not approved by the Underwriters), or any material omission or alleged material omission to state therein a fact necessary in order to make the statements therein contain all information in the context of the offering of the Offered ADSs or otherwise required to be stated therein; in each of (i), (ii), or (iii), except insofar as such losses, claims, damages or liabilities arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information relating to any Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use therein, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in subsection (c) below; or (iv) any role, service, participation or involvement of any Underwriter in connection with any CSRC Filing or pursuant to the CSRC Filing Rules.

(b) [Reserved.]

(c) Indemnification of the Company. Each Underwriter agrees, severally and not jointly, to indemnify and hold harmless the Company, its directors, its officers who signed the Registration Statement and each person, if any, who controls the Company within the meaning of Section 15 of the Securities Act or Section 20 of the Exchange Act, but only with respect to any losses, claims, damages or liabilities that arise out of, or are based upon, any untrue statement or omission or alleged untrue statement or omission made in reliance upon and in conformity with any information relating to such Underwriter furnished to the Company in writing by such Underwriter through the Representatives expressly for use in the Registration Statement, the Prospectus (or any amendment or supplement thereto), any Issuer Free Writing Prospectus, any road show or any Pricing Disclosure Package (including any Pricing Disclosure

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Package that has subsequently been amended), it being understood and agreed upon that the only such information furnished by any Underwriter consists of the following information in the Registration Statement, Pricing Disclosure Package and the Prospectus furnished on behalf of each Underwriter: the statements regarding delivery of shares by the Underwriters set forth on the cover page, the concession and reallowance figures appearing in the sixth paragraph under the caption “Underwriting” and the information contained in the first and second sentences of the third paragraph and the section entitled “Stabilization” under the caption “Underwriting.”

(d) Notice and Procedures. If any suit, action, proceeding (including any governmental or regulatory investigation), claim or demand shall be brought or asserted against any person in respect of which indemnification may be sought pursuant to either paragraph (a) or (b) above, such person (the “Indemnified Person”) shall promptly notify the person against whom such indemnification may be sought (the “Indemnifying Person”) in writing; provided, that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have under paragraph (a) or (b) above except to the extent that it has been materially prejudiced (through the forfeiture of substantive rights or defenses) by such failure; and provided, further, that the failure to notify the Indemnifying Person shall not relieve it from any liability that it may have to an Indemnified Person otherwise than under paragraph (a) or (b) above. If any such proceeding shall be brought or asserted against an Indemnified Person and it shall have notified the Indemnifying Person thereof, the Indemnifying Person shall retain counsel reasonably satisfactory to the Indemnified Person (who shall not, without the consent of the Indemnified Person, be counsel to the Indemnifying Person) to represent the Indemnified Person and any others entitled to indemnification pursuant to this Section 9(d) that the Indemnifying Person may designate in such proceeding and shall pay the reasonably incurred fees and expenses in such proceeding and shall pay the fees and expenses of such counsel related to such proceeding, as incurred. In any such proceeding, any Indemnified Person shall have the right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such Indemnified Person unless (i) the Indemnifying Person and the Indemnified Person shall have mutually agreed to the contrary; (ii) the Indemnifying Person has failed within a reasonable time to retain counsel reasonably satisfactory to the Indemnified Person; (iii) the Indemnified Person shall have reasonably concluded that there may be legal defenses available to it that are different from or in addition to those available to the Indemnifying Person; or (iv) the named parties in any such proceeding (including any impleaded parties) include both the Indemnifying Person and the Indemnified Person and representation of both parties by the same counsel would be inappropriate due to actual or potential differing interests between them. It is understood and agreed that the Indemnifying Person shall not, in connection with any proceeding or related proceeding in the same jurisdiction, be liable for the fees and expenses of more than one separate firm (in addition to any local counsel) for all Indemnified Persons, and that all such fees and expenses shall be paid or reimbursed as they are incurred upon receipt from the Indemnified Person of a written request thereof accompanied by a written statement with reasonable supporting detail of such fees and expenses. Any such separate firm for any Underwriter, its affiliates, directors and officers and any control persons of such Underwriter shall be designated in writing by Goldman Sachs (Asia) L.L.C. and Jefferies LLC and any such separate firm for the Company, its directors, its officers who signed the Registration Statement and any control persons of the Company shall be designated in writing by the Company. The Indemnifying Person shall not be liable for any settlement of any proceeding effected without its written consent, but if settled with such consent or if there be a final judgment for the plaintiff, the

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Indemnifying Person agrees to indemnify each Indemnified Person from and against any loss or liability by reason of such settlement or judgment. Notwithstanding the foregoing sentence, if at any time an Indemnified Person shall have requested that an Indemnifying Person reimburse the Indemnified Person for fees and expenses of counsel as contemplated by this paragraph, the Indemnifying Person shall be liable for any settlement of any proceeding effected without its written consent if (i) such settlement is entered into more than 30 days after receipt by the Indemnifying Person of such request and (ii) the Indemnifying Person shall not have reimbursed the Indemnified Person in accordance with such request prior to the date of such settlement. No Indemnifying Person shall, without the written consent of the Indemnified Person, effect any settlement of any pending or threatened proceeding in respect of which any Indemnified Person is or could have been a party and indemnification could have been sought hereunder by such Indemnified Person, unless such settlement (x) includes an unconditional release of such Indemnified Person, in form and substance reasonably satisfactory to such Indemnified Person, from all liability on claims that are the subject matter of such proceeding and (y) does not include any statement as to or any admission of fault, culpability or a failure to act by or on behalf of any Indemnified Person.

(e) Contribution. If the indemnification provided for in paragraphs (a), (b) or (c) above is unavailable to an Indemnified Person or insufficient in respect of any losses, claims, damages or liabilities referred to therein, then each Indemnifying Person under such paragraph, in lieu of indemnifying such Indemnified Person thereunder, shall contribute to the amount paid or payable by such Indemnified Person as a result of such losses, claims, damages or liabilities (i) in such proportion as is appropriate to reflect the relative benefits received by the Company, on the one hand, and the Underwriters on the other, from the offering of the Offered ADSs or (ii) if the allocation provided by clause (i) is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) but also the relative fault of the Company, on the one hand, and the Underwriters on the other, in connection with the statements or omissions that resulted in such losses, claims, damages or liabilities, as well as any other relevant equitable considerations. The relative benefits received by the Company, on the one hand, and the Underwriters on the other, shall be deemed to be in the same respective proportions as the net proceeds (before deducting expenses) received by the Company from the sale of the Offered ADSs and the total underwriting discounts and commissions received by the Underwriters in connection therewith, in each case as set forth in the table on the cover of the Prospectus, bear to the aggregate offering price of the Offered ADSs. The relative fault of the Company, on the one hand, and the Underwriters on the other, shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company or by the Underwriters and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such statement or omission.

(f) Limitation on Liability. The Company and the Underwriters agree that it would not be just and equitable if contribution pursuant to paragraph (e) above were determined by pro rata allocation (even if the Underwriters were treated as one entity for such purpose) or by any other method of allocation that does not take account of the equitable considerations referred to in paragraph (e) above. The amount paid or payable by an Indemnified Person as a result of the losses, claims, damages and liabilities referred to in paragraph (e) above shall be deemed to include, subject to the limitations set forth above, any legal or other expenses reasonably

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incurred by such Indemnified Person in connection with any such action or claim. Notwithstanding the provisions of paragraphs (e) and (f), in no event shall an Underwriter be required to contribute any amount in excess of the amount by which the total underwriting discounts and commissions received by such Underwriter with respect to the offering of the ADSs exceeds the amount of any damages that such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Securities Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations to contribute pursuant to paragraphs (e) and (f) are several in proportion to their respective purchase obligations hereunder and not joint.

(g) Non-Exclusive Remedies. The remedies provided for in paragraphs (a) through (f) are not exclusive and shall not limit any rights or remedies which may otherwise be available to any Indemnified Person at law or in equity.

10. Effectiveness of Agreement. This Agreement shall become effective as of the date first written above.

11. Termination. This Agreement may be terminated in the absolute discretion of the Representatives, by notice to the Company, if after the execution and delivery of this Agreement and on or prior to the Closing Date or, in the case of the Option ADSs, prior to the Additional Closing Date (i) trading generally shall have been suspended or materially limited on or by any of the New York Stock Exchange, the Nasdaq Exchange or the HK Exchange; (ii) trading of any securities issued or guaranteed by the Company shall have been suspended on any exchange or in any over-the-counter market; (iii) a general moratorium on commercial banking activities shall have been declared by federal or New York State authorities; (iv) there shall have occurred any outbreak or escalation of hostilities or any change in financial markets or any calamity or crisis, either within or outside the United States, that, in the judgment of the Representatives, is material and adverse and makes it impracticable or inadvisable to proceed with the offering, sale or delivery of the Offered ADSs on the Closing Date or the Additional Closing Date, as the case may be, on the terms and in the manner contemplated by this Agreement, the Pricing Disclosure Package and the Prospectus; (v) overseas securities offerings by the Company shall have been prohibited by the CSRC pursuant to Article 8 of the CSRC Filing Rules; or (vi) to the knowledge of the Representatives, or in the reasonable judgment of the Representatives, there shall be any material non-compliance with the CSRC Rules.

12. Defaulting Underwriter.

(a) If, on the Closing Date or the Additional Closing Date, as the case may be, any Underwriter defaults on its obligation to purchase the Offered ADSs that it has agreed to purchase hereunder on such date, the non-defaulting Underwriters may in their discretion arrange for the purchase of such Offered ADSs by other persons satisfactory to the Company on the terms contained in this Agreement. If, within 36 hours after any such default by any Underwriter, the non-defaulting Underwriters do not arrange for the purchase of such Offered ADSs, then the Company shall be entitled to a further period of 36 hours within which to procure other persons satisfactory to the non-defaulting Underwriters to purchase such Offered ADSs on

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such terms. If other persons become obligated or agree to purchase the Offered ADSs of a defaulting Underwriter, either the non-defaulting Underwriters or the Company may postpone the Closing Date or the Additional Closing Date, as the case may be, for up to five full business days in order to effect any changes that in the opinion of counsel for the Company or counsel for the Underwriters may be necessary in the Registration Statement and the Prospectus or in any other document or arrangement, and the Company agrees to promptly prepare any amendment or supplement to the Registration Statement and the Prospectus that effects any such changes. As used in this Agreement, the term “Underwriter” includes, for all purposes of this Agreement unless the context otherwise requires, any person not listed in Schedule 1 hereto that, pursuant to this Section 12, purchases Offered ADSs that a defaulting Underwriter agreed but failed to purchase.

(b) If, after giving effect to any arrangements for the purchase of the Offered ADSs of a defaulting Underwriter or Underwriters by the non-defaulting Underwriters, the Company as provided in paragraph (a) above, the aggregate number of Offered ADSs that remain unpurchased on the Closing Date or the Additional Closing Date, as the case may be, does not exceed one-eleventh of the aggregate number of Offered ADSs to be purchased on such date, then the Company shall have the right to require each non-defaulting Underwriter to purchase the number of Offered ADSs that such Underwriter agreed to purchase hereunder on such date plus such Underwriter’s pro rata share (based on the number of Offered ADSs that such Underwriter agreed to purchase on such date) of the Offered ADSs of such defaulting Underwriter or Underwriters for which such arrangements have not been made.

(c) If, after giving effect to any arrangements for the purchase of the Offered ADSs of a defaulting Underwriter or Underwriters by the non-defaulting Underwriters, the Company as provided in paragraph (a) above, the aggregate number of Offered ADSs that remain unpurchased on the Closing Date or the Additional Closing Date, as the case may be, exceeds one-eleventh of the aggregate amount of Offered ADSs to be purchased on such date, or if the Company shall not exercise the right described in paragraph (b) above, then this Agreement or, with respect to any Additional Closing Date, the obligation of the Underwriters to purchase Offered ADSs on the Additional Closing Date shall terminate without liability on the part of the non-defaulting Underwriters. Any termination of this Agreement pursuant to this Section 12 shall be without liability on the part of the Company, except that the Company will continue to be liable for the payment of expenses as set forth in Section 13 hereof and except that the provisions of Section 9 hereof shall not terminate and shall remain in effect.

(d) Nothing contained herein shall relieve a defaulting Underwriter of any liability it may have to the Company or any non-defaulting Underwriter for damages caused by its default.

13. Payment of Expenses.

(a) Whether or not the transactions contemplated by this Agreement are consummated or this Agreement is terminated, the Company will pay or cause to be paid all costs and expenses incident to the performance of its obligations hereunder, including without limitation, (i) the costs incident to the authorization, issuance, sale, preparation and delivery of the Offered ADSs; (ii) the costs incident to the preparation, printing and filing under the

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Securities Act of the Registration Statement, the Preliminary Prospectus, any Issuer Free Writing Prospectus, any Pricing Disclosure Package and the Prospectus (including all exhibits, amendments and supplements thereto) and the distribution thereof; (iii) the costs of reproducing and distributing each of the Transaction Documents; (iv) the fees and expenses of the Company’s counsel and independent accountants; (v) the fees and expenses incurred in connection with the registration or qualification and determination of eligibility for investment of the Offered ADSs under the laws of such jurisdictions as the Representatives may designate and the preparation, printing and distribution of a Blue Sky Memorandum, including the related fees and expenses of counsel for the Underwriters (such fees and expenses of counsel not to exceed $5,000); (vi) the cost of preparing stock certificates; (vii) the costs and charges of any transfer agent and any registrar; (viii) all expenses and application fees incurred in connection with any filing with, and clearance of the offering by, FINRA (such fees and expenses of counsel not to exceed $40,000); (ix) all expenses incurred by the Company in connection with any “road show” presentation to potential investors; (x) all expenses and application fees related to the listing of the Offered ADSs on the Nasdaq Exchange; (xi) all expenses and application fees related to listing of the Ordinary Shares on the HK Exchange; and (xii) all expenses and fees relating to the CSRC Filing Report. It is understood, however, that except as provided in this Section 13(a), the Underwriters will pay all of their costs and expenses incident to the performance of their obligations hereunder, including fees and disbursements of their counsel, any advertising expenses connected with any offers they may make and the travel expenses of their own representatives in connection with any “road show” presentation to potential investors.

(b) If (i) this Agreement is terminated pursuant to clauses (i) or (ii) of Section 11, (ii) the Company for any reason fail to tender the Offered ADSs for delivery to the Underwriters or (iii) the Underwriters decline to purchase the Offered ADSs for any reason permitted under this Agreement (other than following the termination of this Agreement pursuant to clause (iii) or (iv) of Section 11), the Company agrees to reimburse the Underwriters for all documented out-of-pocket costs and expenses (including the fees and expenses of their counsel) reasonably incurred by the Underwriters in connection with this Agreement and the offering contemplated hereby.

14. Persons Entitled to Benefit of Agreement. This Agreement shall inure to the benefit of and be binding upon the parties hereto and their respective successors and the officers and directors and any controlling persons referred to herein, and the affiliates of each Underwriter referred to in Section 9 hereof. Nothing in this Agreement is intended or shall be construed to give any other person any legal or equitable right, remedy or claim under or in respect of this Agreement or any provision contained herein. No purchaser of Offered ADSs from any Underwriter shall be deemed to be a successor merely by reason of such purchase.

15. Survival. The respective indemnities, rights of contribution, representations, warranties and agreements of the Company and the Underwriters contained in this Agreement or made by or on behalf of the Company or the Underwriters pursuant to this Agreement or any certificate delivered pursuant hereto shall survive the delivery of and payment for the Offered ADSs and shall remain in full force and effect, regardless of any termination of this Agreement or any investigation made by or on behalf of the Company or the Underwriters or the directors, officers, controlling persons or affiliates referred to in Section 9 hereof.

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16. Certain Defined Terms. For purposes of this Agreement, (a) except where otherwise expressly provided, the term “affiliate” has the meaning set forth in Rule 405 under the Securities Act; (b) the term “business day” means any day other than a day on which banks are permitted or required to be closed in New York City; and (c) the term “subsidiary” has the meaning set forth in Rule 405 under the Securities Act.

17. Compliance with USA Patriot Act. In accordance with the requirements of the USA Patriot Act (Title III of Pub. L. 107-56 (signed into law October 26, 2001)), the Underwriters are required to obtain, verify and record information that identifies their respective clients, including the Company, which information may include the name and address of their respective clients, as well as other information that will allow the Underwriters to properly identify their respective clients.

18. Miscellaneous.

(a) Notices. All notices and other communications hereunder shall be in writing and shall be deemed to have been duly given if mailed or transmitted and confirmed by any standard form of telecommunication. Notices to the Underwriters shall be given to the Representatives at: c/o Goldman Sachs (Asia) L.L.C., 68th Floor, Cheung Kong Center, 2 Queen’s Road Central, Hong Kong, Attention: Equity Capital Markets; c/o Jefferies LLC, 520 Madison Avenue, New York, New York 10022, Attention: General Counsel; c/o Leerink Partners LLC, 1301 Avenue of the Americas, 5th Floor, New York, New York 10019, Attention: Stuart R. Nayman, Legal, (fax: (646) 499-7051). Notices to the Company shall be given to it at Zai Lab Limited, 314 Main Street, 4th Floor, Suite 100, Cambridge, MA, 02142 Attention: Josh Smiley.

(b) Governing Law. This Agreement and any claim, controversy or dispute arising under or related to this Agreement shall be governed by and construed in accordance with the laws of the State of New York.

(c) Judgment Currency. In respect of any judgment or order being given or made for any amount due hereunder that is expressed and paid in a currency (the “judgment currency”) other than U.S. dollars, the Company will indemnify each Underwriter against any loss incurred by such Underwriter as a result of any variation as between (i) the rate of exchange at which the U.S. dollar amount is converted into the judgment currency for the purpose of such judgment or order and (ii) the rate of exchange at which such Indemnified Person is able to purchase U.S. dollars with the amount of the judgment currency actually received by the Indemnified Person. The foregoing indemnity shall constitute a separate and independent obligation of the Company and shall continue in full force and effect notwithstanding any such judgment or order as aforesaid. The term “rate of exchange” shall include any premiums and costs of exchange payable in connection with the purchase of or conversion into the relevant currency.

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(d) Submission to Jurisdiction. Each of the parties hereto irrevocably submits to the non-exclusive jurisdiction of any New York State or United States Federal court sitting in The City of New York over any suit, action or proceeding involving any of the parties hereto that arises out of or relates to this Agreement or the transactions contemplated hereby. Each of the Company irrevocably waives any objection which it may now or hereafter have to the laying of venue of any such suit, action or proceeding brought in such a court and any claim that any such suit, action or proceeding brought in such a court has been brought in an inconvenient forum. The Company has appointed Cogency Global Inc. (the “Authorized Agent”) as its agent for service of process in any suit, action or proceeding described in this Section 18(d) and agrees that service of process in any such suit, action or proceeding may be made upon it at the office of such agent. The Company waives, to the fullest extent permitted by law, any other requirements of or objections to personal jurisdiction with respect thereto. The Company represents and warrants that the Authorized Agent has agreed to act as the Company’s agent for service of process, and the Company agrees to take any and all action, including the filing of any and all documents and instruments, that may be necessary to continue such appointment in full force and effect.

(e) Waiver of Jury Trial. Each of the parties hereto hereby waives any right to trial by jury in any suit or proceeding arising out of or relating to this Agreement.

(f) Recognition of the U.S. Special Resolution Regimes.

(i) In the event that any Underwriter that is a Covered Entity becomes subject to a proceeding under a U.S. Special Resolution Regime, the transfer from such Underwriter of this Agreement, and any interest and obligation in or under this Agreement, will be effective to the same extent as the transfer would be effective under the U.S. Special Resolution Regime if this Agreement, and any such interest and obligation, were governed by the laws of the United States or a state of the United States.

(ii) In the event that any Underwriter that is a Covered Entity or a BHC Act Affiliate of such Underwriter becomes subject to a proceeding under a U.S. Special Resolution Regime, Default Rights under this Agreement that may be exercised against such Underwriter are permitted to be exercised to no greater extent than such Default Rights could be exercised under the U.S. Special Resolution Regime if this Agreement were governed by the laws of the United States or a state of the United States.

As used in this Section 18(f):

“BHC Act Affiliate” has the meaning assigned to the term “affiliate” in, and shall be interpreted in accordance with, 12 U.S.C. § 1841(k).

“Covered Entity” means any of the following:

(i) a “covered entity” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 252.82(b);

(ii) a “covered bank” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 47.3(b); or

42

(iii) a “covered FSI” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 382.2(b).

“Default Right” has the meaning assigned to that term in, and shall be interpreted in accordance with, 12 C.F.R. §§ 252.81, 47.2 or 382.1, as applicable.

“U.S. Special Resolution Regime” means each of (i) the Federal Deposit Insurance Act and the regulations promulgated thereunder and (ii) Title II of the Dodd-Frank Wall Street Reform and Consumer Protection Act and the regulations promulgated thereunder.

(g) Counterparts. This Agreement may be signed in counterparts (which may include counterparts delivered by any standard form of telecommunication), each of which shall be an original and all of which together shall constitute one and the same instrument. The words “execution,” “signed,” “signature,” “delivery,” and words of like import in or relating to this Agreement or any document to be signed in connection with this Agreement shall be deemed to include electronic signatures, deliveries or the keeping of records in electronic form, each of which shall be of the same legal effect, validity or enforceability as a manually executed signature, physical delivery thereof or the use of a paper-based recordkeeping system, as the case may be, and the parties hereto consent to conduct the transactions contemplated hereunder by electronic means.

(h) Amendments or Waivers. No amendment or waiver of any provision of this Agreement, nor any consent or approval to any departure therefrom, shall in any event be effective unless the same shall be in writing and signed by the parties hereto.

(i) Headings. The headings herein are included for convenience of reference only and are not intended to be part of, or to affect the meaning or interpretation of, this Agreement.

43

If the foregoing is in accordance with your understanding, please indicate your acceptance of this Agreement by signing in the space provided below.

[Signature Page to Underwriting Agreement]

Accepted: As of the date first written above

For themselves and on behalf of the

several Underwriters listed in

Schedule 1 hereto.

[Signature Page to Underwriting Agreement]

Schedule 1

Sch. 1-1

Annex A

The initial price to the public of the Underwritten ADSs is US$25.50 per ADS.

Underwritten ADSs: 7,843,137

Option ADSs: 1,176,470

Public Offering Price Per ADS: $25.50

Trade Date: November 14, 2024

Settlement Date: November 18, 2024

Annex A-1

Annex B

Pricing Term Sheet

None.

Annex B-1

Exhibit A

Form of Waiver of Lock-up

Zai Lab Limited

_____________, 20______

[Name and Address of

Officer or Director

Requesting Waiver]

Dear Mr./Ms. [Name]:

This letter is being delivered to you in connection with the offering by Zai Lab Limited (the “Company”) of American Depositary Shares (“ADSs”), representing [ ] ordinary shares, par value $0.000006 per share (the “Ordinary Shares”) of the Company (the “Underwritten ADSs”) and the lock-up letter dated _________, 20___ (the “Lock-up Letter”), executed by you in connection with such offering, and your request for a [waiver] [release] dated , 20 , with respect to shares of Underwritten ADSs.

Goldman Sachs (Asia) L.L.C. and Jefferies LLC hereby agrees to [waive] [release] the transfer restrictions set forth in the Lock-up Letter, but only with respect to the ADSs, effective _________, 20___. This letter will serve as notice to the Company of the impending [waiver] [release].

Except as expressly [waived] [released] hereby, the Lock-up Letter shall remain in full force and effect.

[Signature Page Follows]

cc: Zai Lab Limited

Exhibit B

FORM OF LOCK-UP AGREEMENT

[  ], 2024

GOLDMAN SACHS (ASIA) L.L.C.

JEFFERIES LLC

LEERINK PARTNERS LLC

As Representatives of the

several Underwriters listed

in Schedule 1 to the Underwriting Agreement referred to below

c/o Goldman Sachs (Asia) L.L.C.

68^th Floor, Cheung Kong Center

2 Queen’s Road Central

Hong Kong

c/o Jefferies LLC

520 Madison Avenue

New York, New York 10022

c/o Leerink Partners LLC

1301 Avenue of the Americas, 5th Floor

New York, New York 10019

Re: Zai Lab Limited — Public Offering

Ladies and Gentlemen:

The undersigned understands that you, as Representatives of the several Underwriters, propose to enter into an underwriting agreement (the “Underwriting Agreement”) with Zai Lab Limited, an exempted company incorporated with limited liability under the laws of the Cayman Islands (the “Company”) providing for the public offering (the “Public Offering”) by the several Underwriters named in Schedule 1 to the Underwriting Agreement (the “Underwriters”), of American Depositary Shares (“ADSs”) representing ordinary shares, par value $0.000006 per share, of the Company (the “Ordinary Shares”). Capitalized terms used herein and not otherwise defined shall have the meanings set forth in the Underwriting Agreement.

In consideration of the Underwriters’ agreement to purchase and make the Public Offering of the ADSs, and for other good and valuable consideration receipt of which is hereby acknowledged, the undersigned hereby agrees that, without the prior written consent of Goldman Sachs (Asia) L.L.C. and Jefferies LLC on behalf of the Underwriters, the undersigned will not, during the period beginning on the date of this letter agreement (this “Letter Agreement”) and ending 90 days after the date of the prospectus relating to the Public Offering (the “Prospectus”) (such period, the “Restricted Period”), (1) offer, pledge, sell, contract to sell, sell any option or

B-1

contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, or otherwise transfer or dispose of, directly or indirectly, any ADSs or Ordinary Shares of the Company or any securities convertible into or exercisable or exchangeable for ADSs or Ordinary Shares (including without limitation, ADSs or Ordinary Shares or such other securities which may be deemed to be beneficially owned by the undersigned in accordance with the rules and regulations of the Securities and Exchange Commission and securities which may be issued upon exercise of a stock option or warrant), or publicly disclose the intention to make any offer, sale, pledge or disposition, (2) enter into any swap or other agreement that transfers, in whole or in part, any of the economic consequences of ownership of the ADSs or Ordinary Shares or such other securities, whether any such transaction described in clause (1) or (2) above is to be settled by delivery of ADSs or Ordinary Shares or such other securities, in cash or otherwise or (3) make any demand for or exercise any right with respect to the registration of any ADSs or Ordinary Shares or any security convertible into or exercisable or exchangeable for ADSs or Ordinary Shares in each case other than (A) transfers of shares of ADSs or Ordinary Shares or such other securities as a bona fide gift or gifts or by testate succession or intestate distribution, (B) any ADSs or Ordinary Shares acquired by the undersigned in the open market, (C) the exercise of stock options or other similar awards granted pursuant to the Company’s equity incentive plans, as disclosed in the Registration Statement; provided, that such restriction shall apply to any of the undersigned’s ADSs or Ordinary Shares issued upon such exercise, (D) any ADSs or Ordinary Shares or such other securities that are used for the primary purpose of satisfying any tax or other governmental withholding obligation, through cashless surrender or otherwise, with respect to any award or equity-based compensation granted pursuant to the Company’s equity incentive plans, as disclosed in the Registration Statement, or in connection with tax or other obligations as a result of testate succession or intestate distribution, (E) transfers to a member or members of the undersigned’s immediate family or to a trust, the direct or indirect beneficiaries of which are the undersigned and/or a member or members of his or her immediate family, (F) the transfer of the undersigned’s ADSs or Ordinary Shares or any security convertible into or exercisable or exchangeable for ADSs or Ordinary Shares to the Company pursuant to any contractual arrangement that provides for the repurchase of the undersigned’s ADSs or Ordinary Shares or such other securities by the Company or in connection with the termination of the undersigned’s employment with the Company or the undersigned’s failure to meet certain conditions set out upon receipt of such ADSs or Ordinary Shares or other such securities and (G) distributions of ADSs, Ordinary Shares or such other securities to members or shareholders of the undersigned or to any corporation, partnership or other person or entity that is a direct or indirect affiliate of the undersigned; provided, that in the case of any transfer or distribution pursuant to clause (A), (E) or (G), each donee or distributee shall execute and deliver to the Representatives a lock-up letter in the form of this paragraph; and provided, further, that in the case of any transfer or distribution pursuant to clause (A) through (G), no filing by any party (donor, donee, transferor or transferee) under the Securities Exchange Act of 1934, as amended, or other public announcement shall be required or shall be made voluntarily in connection with such transfer or distribution (other than a filing on a Form 5 made after the expiration of the Restricted Period referred to above), unless, in the case of a bona fide gift or gifts transferred pursuant to clause (A), such filing, report or announcement shall clearly indicate in the footnotes thereto the nature and conditions of such transfer. If the undersigned is an officer or director of the Company, the undersigned further agrees that the foregoing provisions shall be equally applicable to any Company directed securities the undersigned may purchase in the Public Offering.

B-2

The restrictions contained herein shall not apply to any transfers, sales, tenders or other dispositions of ADSs or Ordinary Shares or any security convertible into or exercisable or exchangeable for ADSs or Ordinary Shares pursuant to a bona fide third party tender offer, merger, amalgamation, consolidation or other similar transaction made to or involving all holders of ADSs or Ordinary Shares or such other securities pursuant to which one hundred percent (100%) ownership of the Company is transferred to such third party (including, without limitation, the entering into any lock-up, voting or similar agreement pursuant to which the undersigned may agree to transfer, sell, tender or otherwise dispose of ADSs or Ordinary Shares or other such securities in connection with such transaction, or vote any ADSs or Ordinary Shares or other such securities in favor of any such transaction); provided, that if such tender offer merger, amalgamation, consolidation or other similar transaction is not completed, any ADSs or Ordinary Shares or any security convertible into or exercisable or exchangeable for ADSs or Ordinary Shares subject to this Letter Agreement shall remain subject to the restrictions contained in this Letter Agreement.

The foregoing restrictions shall not apply to: (a) any sales made pursuant to a trading plan adopted pursuant to Rule 10b5-1 of the Exchange Act prior to the date of this Letter Agreement, provided, that any filing under Section 16(a) of the Exchange Act that is made in connection with any such sales during the Restricted Period shall state that such sales have been executed under a trading plan pursuant to Rule 10b5-1 under the Exchange Act, and shall also state the date such trading plan was adopted; or (b) the establishment of a trading plan pursuant to Rule 10b5-1 under the Exchange Act, provided that (i) such plan does not provide for transfers of the Company’s securities during the Restricted Period, and (ii) to the extent a public announcement or filing under the Exchange Act, if any, is required by or on behalf of the undersigned or the Company regarding the establishment of a Rule 10b5-1 Trading Plan during the Restricted Period, such announcement or filing shall include a statement to the effect that no transfer of Common Stock may be made under such Rule 10b5-1 Trading Plan during the Restricted Period.

If the undersigned is an officer or director of the Company, (i) Goldman Sachs (Asia) L.L.C. and Jefferies LLC on behalf of the Underwriters agree that, at least three business days before the effective date of any release or waiver of the foregoing restrictions in connection with a transfer of shares of ADSs or Ordinary Shares, Goldman Sachs (Asia) L.L.C. and Jefferies LLC on behalf of the Underwriters will notify the Company of the impending release or waiver, and (ii) the Company has agreed in the Underwriting Agreement to announce the impending release or waiver by press release through a major news service at least two business days before the effective date of the release or waiver. Any release or waiver granted by Goldman Sachs (Asia) L.L.C. and Jefferies LLC on behalf of the Underwriters hereunder to any such officer or director shall only be effective two business days after the publication date of such press release. The provisions of this paragraph will not apply if (a) the release or waiver is effected solely to permit a transfer not for consideration and (b) the transferee has agreed in writing to be bound by the same terms described in this letter to the extent and for the duration that such terms remain in effect at the time of the transfer.

B-3

In furtherance of the foregoing, the Company, and any duly appointed transfer agent for the registration or transfer of the securities described herein, are hereby authorized to decline to make any transfer of securities if such transfer would constitute a violation or breach of this Letter Agreement.

The undersigned hereby represents and warrants that the undersigned has full power and authority to enter into this Letter Agreement. All authority herein conferred or agreed to be conferred and any obligations of the undersigned shall be binding upon the successors, assigns, heirs or personal representatives of the undersigned.

The undersigned understands that, (i) if the Underwriting Agreement does not become effective by December 31, 2024, (ii) if the Underwriting Agreement (other than the provisions thereof which survive termination) shall terminate or be terminated prior to payment for and delivery of the ADSs to be sold thereunder, (iii) if the Representatives, on the one hand, or the Company, on the other hand, informs the other, prior to the execution of the Underwriting Agreement, that it has determined not to proceed with the Public Offering or (iv) the registration statement related to the Public Offering has been withdrawn, the undersigned shall be released from all obligations under this Letter Agreement. The undersigned understands that the Underwriters are entering into the Underwriting Agreement and proceeding with the Public Offering in reliance upon this Letter Agreement.

This Letter Agreement and any claim, controversy or dispute arising under or related to this Letter Agreement shall be governed by and construed in accordance with the laws of the State of New York.

B-4

Exhibit 5.1

Office: +852 2801 6066

Mobile: +852 9718 8740

Email: rthorp@tta.lawyer

Zai Lab Limited

Harbour Place 2nd Floor

103 South Church Street

P.O. Box 472, George Town

Grand Cayman KYI-1106

Cayman Islands

15 November 2024

Dear Sirs

Zai Lab Limited

We have acted as Cayman Islands legal advisers to Zai Lab Limited (the “Company”) in connection with the Company’s registration statement on Form S-3ASR (File No. 333-278843) (the “Base Prospectus”), filed with the United States Securities and Exchange Commission (the “Commission”) under the United States Securities Act of 1933 (the “Act”) on April 19, 2024, and the final prospectus supplement dated November 14, 2024, (including all amendments or supplements thereto (together with the Base Prospectus, the “Registration Statement”) related to the offering by the Company of American Depositary Shares representing ten of its ordinary shares, par value of US$0.000006 per share (the “Shares”). This opinion is given in accordance with the terms of the Legal Matters section of the Registration Statement.

For the purposes of this opinion, we have reviewed originals, copies, drafts or conformed copies of the documents listed in Schedule 1 to this opinion, being all of the documents necessary to form our opinion. Defined terms shall have the meanings set out in Schedule 1 or in the Registration Statement.

The following opinions are given only as to and based on circumstances and matters of fact existing at the date hereof and as to the laws of the Cayman Islands as the same are in force at the date hereof. In giving this opinion, we have relied upon the completeness and accuracy (and assumed the continuing completeness and accuracy as at the date hereof) of the Certificate of Good Standing and the Director’s Certificate, as to matters of fact, without further verification and have assumed that copy documents or drafts of documents provided to us are true and complete copies of, or in the final forms of, the originals.

Based upon, and subject to, the foregoing assumptions, and having regard to such legal considerations as we deem relevant, we are of the opinion that:

We hereby consent to the prospectus discussion of this opinion, to the filing of this opinion as an exhibit to the Registration Statement and to the reference to our firm under the headings “Enforcement of civil liabilities” and “Legal Matters” and elsewhere in the prospectus included in the Registration Statement. In providing our consent, we do not thereby admit that we are in the category of persons whose consent is required under Section 7 of the Act or the Rules and Regulations of the Commission thereunder.

This opinion is limited to the matters detailed herein and is not to be read as an opinion with respect to any other matter.

Yours faithfully

/s/ Travers Thorp Alberga

TRAVERS THORP ALBERGA

SCHEDULE 1

List of Documents Reviewed

Exhibit 99.1

Zai Lab Announces Pricing of Public Offering of American Depositary Shares

SHANGHAI & CAMBRIDGE, Mass., November 14, 2024 (GLOBE NEWSWIRE) – Zai Lab Limited (“Zai Lab” or the “Company”) (NASDAQ: ZLAB; HKEX: 9688), an innovative, commercial-stage biopharmaceutical company, today announced the pricing of its underwritten public offering of 7,843,137 American depositary shares (“ADSs”), each representing ten ordinary shares of the Company, at a price of US$25.50 per ADS.

The gross proceeds to Zai Lab from the offering, before deducting underwriting discounts and commissions and other offering expenses, are expected to be approximately $200 million. Subject to customary closing conditions, the underwriters expect to deliver the ADSs against payment to the purchasers on or about November 18, 2024, on a “T+2” basis. In addition, Zai Lab has granted the underwriters a 30-day option to purchase up to an additional 1,176,470 ADSs at the public offering price, less underwriting discounts and commissions. Zai Lab intends to use the net proceeds from this offering for general corporate purposes.

Goldman Sachs (Asia) L.L.C., Jefferies and Leerink Partners are acting as joint book-running managers for the ADS offering.

The ADSs are offered pursuant to a shelf registration statement on Form S-3ASR, which became automatically effective upon filing with the U.S. Securities and Exchange Commission (“SEC”) on April 19, 2024 (the “Form S-3ASR”). The offering is being made only by means of a prospectus supplement and an accompanying base prospectus included in the Form S-3ASR. A final prospectus supplement relating to the offering will be filed with the SEC. The registration statement on Form S-3ASR and the prospectus supplement are available at the SEC’s website at: http://www.sec.gov. Copies of the prospectus supplement and the accompanying prospectus may be obtained from: (i) Goldman Sachs & Co. LLC, c/o Prospectus Department, 200 West Street, New York, NY, facsimile: 212-902-9316 or by emailing Prospectus-ny@ny.email.gs.com, (ii) Jefferies LLC, c/o Equity Syndicate Prospectus Department, 520 Madison Avenue, New York, NY 10022, by telephone at (877) 821-7388, or by email at Prospectus_Department@Jefferies.com, and (iii) Leerink Partners LLC, c/o Syndicate Department, 53 State Street, 40th Floor, Boston, MA 02109, by telephone at (800) 808-7525, ext. 6105, or by email at syndicate@leerink.com.

This press release does not constitute an offer to sell or the solicitation of an offer to buy ADSs or any other securities, nor shall there be any sale of ADSs in any state or jurisdiction in which such an offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

About Zai Lab

Zai Lab (NASDAQ: ZLAB; HKEX: 9688) is an innovative, research-based, commercial-stage biopharmaceutical company based in China and the United States. Zai Lab is focused on discovering, developing, and commercializing innovative products that address medical conditions with significant unmet needs in the areas of oncology, immunology, neuroscience, and infectious disease. The Company’s goal is to leverage its competencies and resources to positively impact human health in China and worldwide.

Zai Lab Forward-Looking Statements

This press release contains forward-looking statements about future expectations, plans, and prospects for Zai Lab, including, without limitation, statements relating to our ability to successfully complete the offering on the timeline and with the terms and conditions satisfactory to us, the anticipated use of proceeds therefrom, the possible adverse impact on the market price of our ADSs and ordinary shares due to the dilutive effect of the securities to be sold in the offering, capital market risks, and the impact of general economic or industry conditions. All statements, other than statements of historical fact, included in this press release are forward-looking statements and can be identified

by containing words such as “aim,” “anticipate,” “believe,” “could,” “estimate,” “expect,” “forecast,” “goal,” “intend,” “may,” “plan,” “possible,” “potential,” “will,” “would,” and other similar expressions. Such statements constitute forward-looking statements within the meaning of U.S. federal securities laws. Forward-looking statements are not guarantees or assurances of future performance. There can be no assurance that we will be able to complete the public offering on the anticipated terms, or at all. Forward-looking statements are based on our expectations and assumptions as of the date of this press release and are subject to inherent uncertainties, risks, and changes in circumstances that may differ materially from those contemplated by the forward-looking statements. We may not actually achieve the plans, carry out the intentions, or meet the expectations or projections disclosed in our forward-looking statements, and you should not place undue reliance on these forward-looking statements. Actual results may differ materially from those indicated by forward-looking statements as a result of various important factors, including but not limited to (1) our ability to successfully commercialize and generate revenue from our approved products, (2) our ability to obtain funding for our operations and business initiatives, (3) the results of our clinical and pre-clinical development of our product candidates, (4) the content and timing of decisions made by the relevant regulatory authorities regarding regulatory approvals of our product candidates, (5) risks related to doing business in China, and (6) other factors identified in our most recent annual and quarterly reports and in other reports we have filed with the U.S. Securities and Exchange Commission, including the registration statement and prospectus supplement related to the offering, which are available at www.sec.gov.. We anticipate that subsequent events and developments will cause our expectations and assumptions to change, and we undertake no obligation to update or revise any forward-looking statements, whether as a result of new information, future events, or otherwise, except as may be required by law. These forward-looking statements should not be relied upon as representing our views as of any date subsequent to the date of this press release.

ZAI LAB CONTACTS:

Investor Relations:

Christine Chiou / Lina Zhang

+1 (917) 886-6929 / +86 136 8257 6943

christine.chiou1@zailaboratory.com / lina.zhang@zailaboratory.com

Media:

Shaun Maccoun / Xiaoyu Chen

+1 (857) 270-8854 / +86 185 0015 5011

shaun.maccoun@zailaboratory.com / xiaoyu.chen@zailaboratory.com