TRVI Trevi Therapeutics Inc

Exhibit 1.1

Trevi Therapeutics, Inc.

(a Delaware corporation)

12,500,000 Shares of Common Stock

UNDERWRITING AGREEMENT

December 15, 2024

Leerink Partners LLC

Stifel, Nicolaus & Company, Incorporated

Oppenheimer & Co. Inc.

as Representatives of the several Underwriters

c/o Leerink Partners LLC

1301 Avenue of the Americas, 5^th Floor

New York, NY 10019

c/o Stifel, Nicolaus & Company, Incorporated

787 7^th Avenue, 11^th Floor

New York, NY 10019

c/o Oppenheimer & Co. Inc.

85 Broad Street

New York, NY 10004

Ladies and Gentlemen:

Trevi Therapeutics, Inc., a Delaware corporation (the “Company”), confirms its agreement with Leerink Partners LLC (“Leerink Partners”), Stifel, Nicolaus & Company, Incorporated (“Stifel”) and Oppenheimer & Co. Inc. (“Oppenheimer”), and each of the other Underwriters named in Schedule A hereto (collectively, the “Underwriters,” which term shall also include any underwriter substituted as hereinafter provided in Section 10 hereof), for which Leerink Partners, Stifel and Oppenheimer are acting as representatives (in such capacity, the “Representatives”) with respect to the sale by the Company and the purchase by the Underwriters, acting severally and not jointly, of the respective numbers of shares (the “Shares”) of common stock, par value $0.001 per share, of the Company (the “Common Stock”) set forth on Schedule A hereto.

The Company understands that the Underwriters propose to make an offering of the Shares as soon as the Representatives deem advisable after this Underwriting Agreement (this “Agreement”) has been executed and delivered.

The Company has filed with the Securities and Exchange Commission (the “Commission”) a shelf registration statement on Form S-3 (No. 333-273030), as amended, covering the public offering and sale of certain securities, including the Shares, under the Securities Act of 1933, as amended (the “1933 Act”) and the rules and regulations of the Commission promulgated thereunder (the “1933 Act Regulations”), which shelf registration statement was declared effective on August 15, 2023. Such registration statement, as of any time, means such registration statement as amended by any post-effective amendments thereto to such time, including the exhibits and any schedules thereto at such time, the documents incorporated or deemed to be incorporated by reference therein at such time pursuant to Item 12 of Form S-3 under the 1933 Act and the documents otherwise deemed to be a part thereof as of such time pursuant to Rule 430B under the 1933 Act Regulations (“Rule 430B”), and is referred to herein as the “Registration Statement;” provided, however, that the “Registration Statement” without reference to a time means such registration statement as amended by any post-effective amendments thereto as of the time of the first contract of sale for the Shares, which time shall be considered the “new effective date” of such registration statement with respect to the Shares within the meaning of paragraph (f)(2) of Rule 430B, including the exhibits and schedules thereto as of such time, the documents incorporated or deemed incorporated by reference therein at such time pursuant to Item 12 of Form S-3 under the 1933 Act and the documents otherwise deemed to be a part thereof as of such time pursuant to the Rule 430B. Any registration statement filed pursuant to Rule 462(b) of the 1933 Act Regulations is herein called the “Rule 462(b) Registration Statement” and, after such filing, the term “Registration Statement” shall include the Rule 462(b) Registration Statement. The base prospectus filed as part of the Registration Statement in the form in which it has most recently been filed with the Commission on or prior to the date of this Agreement is herein called the “Base Prospectus.” Any preliminary prospectus used in connection with the offering of the Shares, including the documents incorporated or deemed to be incorporated by reference therein pursuant to Item 12 of Form S-3 under the 1933 Act, are collectively referred to herein as a “preliminary prospectus.” Promptly after execution and delivery of this Agreement, the Company will prepare and file a final prospectus relating to the Shares in accordance with the provisions of Rule 424(b) under the 1933 Act Regulations (“Rule 424(b)”). The final prospectus, in the form first furnished or made available to the Underwriters for use in connection with the offering of the Shares, including the documents incorporated or deemed to be incorporated by reference therein pursuant to Item 12 of Form S-3 under the 1933 Act, are collectively referred to herein as the “Prospectus.” For purposes of this Agreement, all references to the Registration Statement, the Base Prospectus, any preliminary prospectus, the Prospectus or any amendment or supplement to any of the foregoing shall be deemed to include the copy filed with the Commission pursuant to its Electronic Data Gathering, Analysis and Retrieval system (or any successor system) (“EDGAR”).

As used in this Agreement:

“Applicable Time” means 7:35 P.M., New York City time, on December 15, 2024 or such other time as agreed by the Company and the Representatives.

“General Disclosure Package” means the Base Prospectus, as most recently amended or supplemented prior to the Applicable Time, together with any Issuer General Use Free Writing Prospectuses issued at or prior to the Applicable Time that is distributed to investors prior to the Applicable Time and the information included on Schedule B-1 hereto, all considered together.

“Issuer Free Writing Prospectus” means any “issuer free writing prospectus,” as defined in Rule 433 of the 1933 Act Regulations (“Rule 433”), including without limitation any “free writing prospectus” (as defined in Rule 405 of the 1933 Act Regulations (“Rule 405”)) relating to the Shares that is (i) required to be filed with the Commission by the Company, (ii) a “road show for an offering that is a written communication” within the meaning of Rule 433(d)(8)(i), whether or not required to be filed with the Commission, or (iii) exempt from filing with the Commission pursuant to Rule 433(d)(5)(i) because it contains a description of the Shares or of the offering that does not reflect the final terms, in each case in the form filed or required to be filed with the Commission or, if not required to be filed, in the form retained in the Company’s records pursuant to Rule 433(g).

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“Issuer General Use Free Writing Prospectus” means any Issuer Free Writing Prospectus that is intended for general distribution to prospective investors (other than a “bona fide electronic road show,” as defined in Rule 433), as evidenced by its being specified in Schedule B-2 hereto.

“Issuer Limited Use Free Writing Prospectus” means any Issuer Free Writing Prospectus that is not an Issuer General Use Free Writing Prospectus.

“Testing-the-Waters Communication” means any oral or written communication with potential investors undertaken in reliance on Section 5(d) of the 1933 Act or Rule 163B under the 1933 Act.

“Written Testing-the-Waters Communication” means any Testing-the-Waters Communication that is a written communication within the meaning of Rule 405 under the 1933 Act.

All references in this Agreement to financial statements and schedules and other information which is “contained,” “included” or “stated” (or other references of like import) in the Registration Statement, any preliminary prospectus or the Prospectus shall be deemed to include all such financial statements and schedules and other information incorporated or deemed incorporated by reference in the Registration Statement, any preliminary prospectus or the Prospectus, as the case may be, prior to the execution and delivery of this Agreement; and all references in this Agreement to amendments or supplements to the Registration Statement, any preliminary prospectus or the Prospectus shall be deemed to include the filing of any document under the Securities Exchange Act of 1934, as amended, and the rules and regulations promulgated thereunder (collectively, the “1934 Act”), incorporated or deemed to be incorporated by reference in the Registration Statement, such preliminary prospectus or the Prospectus, as the case may be, at or after the execution and delivery of this Agreement.

SECTION 1. Representations and Warranties.

(a) Representations and Warranties by the Company. The Company represents and warrants to each Underwriter as of the date hereof, the Applicable Time, and the Closing Time (as defined below), and agrees with each Underwriter, as follows:

(i) Registration Statement and Prospectuses. The Company meets the requirements for use of Form S-3 under the 1933 Act. Each of the Registration Statement and any amendment thereto has become effective under the 1933 Act. No stop order suspending the effectiveness of the Registration Statement or any post-effective amendment thereto has been issued by the Commission under the 1933 Act, no order preventing or suspending the use of any preliminary prospectus or the Prospectus has been issued by the Commission and no proceedings for any of those purposes have been instituted by the Commission or are pending or, to the Company’s knowledge, contemplated by the Commission. The Company has complied with each request (if any) from the Commission for additional information.

Each of the Registration Statement and any post-effective amendment thereto, at the time of its effectiveness and at each deemed effective date with respect to the Underwriters pursuant to Rule 430B(f)(2) under the 1933 Act Regulations, complied in all material respects with the requirements of the 1933 Act and the 1933 Act Regulations. Any preliminary prospectus, the Prospectus and any amendment or supplement thereto, at the time each was filed with the Commission, complied in all material respects with the requirements of the 1933 Act and the 1933 Act Regulations. Any preliminary prospectus delivered to the Underwriters for use in connection with the offering and the Prospectus was or will be identical to the electronically transmitted copies thereof filed with the Commission pursuant to EDGAR, except to the extent permitted by Regulation S-T.

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The documents incorporated or deemed to be incorporated by reference in the Registration Statement, the General Disclosure Package and the Prospectus, when they became effective or at the time they were or hereafter are filed with the Commission, were or will be filed on a timely basis and complied and will comply in all material respects with the requirements of the 1934 Act and the rules and regulations of the Commission under the 1934 Act (the “1934 Act Regulations”).

The Registration Statement, any preliminary prospectus and the Prospectus, and the filing of the Registration Statement, any preliminary prospectus and the Prospectus with the Commission have been duly authorized by and on behalf of the Company, and the Registration Statement has been duly executed pursuant to such authorization.

(ii) Accurate Disclosure. Neither the Registration Statement nor any amendment thereto, at its effective time or at the Closing Time, contained, contains or will contain an untrue statement of a material fact or omitted, omits or will omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading. As of the Applicable Time, none of (A) the General Disclosure Package, (B) any individual Issuer Limited Use Free Writing Prospectus, when considered together with the General Disclosure Package, nor (C) any individual Written Testing-the-Waters Communication, when considered together with the General Disclosure Package, included, includes or will include an untrue statement of a material fact or omitted, omits or will 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. Neither the Prospectus nor any amendment or supplement thereto (including any prospectus wrapper), as of its issue date, at the time of any filing with the Commission pursuant to Rule 424(b), or at the Closing Time, included, includes or will include an untrue statement of a material fact or omitted, omits or will 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. No document incorporated or deemed to be incorporated by reference in the Registration Statement, the General Disclosure Package and the Prospectus, at the time the Registration Statement became effective or when such document incorporated by reference was or will be filed with the Commission, as the case may be, when read together with the other information in the Registration Statement, the General Disclosure Package or the Prospectus contained or will contain an untrue statement of a material fact or omitted or will omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading.

The representations and warranties in this subsection shall not apply to statements in or omissions from the Registration Statement (or any amendment thereto), the General Disclosure Package or the Prospectus (or any amendment or supplement thereto, including any prospectus wrapper) made in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives expressly for use therein. For purposes of this Agreement, the only information so furnished shall be the information in the first paragraph under the caption “Underwriting—Discounts and Commissions,” in the second, third and sixth paragraphs under the caption “Underwriting—Price Stabilization, Short Positions and Penalty Bids,” and in the sentence under the caption “Underwriting—Electronic Distribution,” in each case contained in the Prospectus (collectively, the “Underwriter Information”).

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(iii) Issuer Free Writing Prospectuses. No Issuer Free Writing Prospectus conflicts or will conflict with the information contained in the Registration Statement or the Prospectus, including any document incorporated by reference therein, or any preliminary or other prospectus deemed to be a part thereof that has not been superseded or modified. No filing of any “road show” (as defined in Rule 433(h)) is required in connection with the offering of the Shares. Any Issuer Free Writing Prospectus that the Company is required to file pursuant to Rule 433(d) under the 1933 Act has been, or will be, filed with the Commission in accordance with the requirements of the 1933 Act and the 1933 Act Regulations. Each Issuer Free Writing Prospectus that the Company has filed, or is required to file, pursuant to Rule 433(d) under the 1933 Act or that was prepared by or on behalf of or used or referred to by the Company complies or will comply in all material respects with the requirements of the 1933 Act and the 1933 Act Regulations. Except for the Issuer Free Writing Prospectuses, if any, identified in Schedule B-2 hereto, and electronic road shows, if any, each furnished to the Representatives before first use, the Company has not prepared, used or referred to, and will not, without the prior consent of the Representatives, prepare, use or refer to, any issuer free writing prospectus.

(iv) Testing-the-Waters Materials. The Company (A) has not engaged in any Testing-the-Waters Communication other than Testing-the-Waters Communications with the consent of the Representatives with entities that are qualified institutional buyers within the meaning of Rule 144A under the 1933 Act or institutions that are accredited investors within the meaning of Rule 501 under the 1933 Act and (B) has not authorized anyone other than the Representatives to engage in Testing-the-Waters Communications. The Company reconfirms that the Representatives have been authorized to act on its behalf in undertaking Testing-the-Waters Communications. The Company has not distributed any Written Testing-the-Waters Communications other than those listed on Schedule B-3 hereto.

(v) Company Not Ineligible Issuer. At the time of filing the Registration Statement and any post-effective amendment thereto, at the earliest time thereafter that the Company or another offering participant made a bona fide offer (within the meaning of Rule 164(h)(2) of the 1933 Act Regulations) of the Shares and at the date hereof, the Company was not and is not an “ineligible issuer,” as defined in Rule 405, without taking account of any determination by the Commission pursuant to Rule 405 that it is not necessary that the Company be considered an ineligible issuer.

(vi) Emerging Growth Company Status. The Company has been, and will be until December 31, 2024, an “emerging growth company,” as defined in Section 2(a) of the 1933 Act (an “Emerging Growth Company”).

(vii) Independent Accountants. Ernst & Young LLP, the accounting firm that certified the financial statements and supporting schedules of the Company that are incorporated by reference in the Registration Statement, the General Disclosure Package and the Prospectus, is an independent registered public accounting firm as required by the 1933 Act, the 1933 Act Regulations, the 1934 Act, the 1934 Act Regulations and the Public Company Accounting Oversight Board (United States).

(viii) Financial Statements; Non-GAAP Financial Measures. The financial statements included or incorporated by reference in the Registration Statement, the General Disclosure Package and the Prospectus, together with the related schedules and notes, comply as to form in all material respects with Regulation S-X under the 1933 Act and present fairly, in all material respects, the financial position of the Company and the Subsidiary (as defined below) at the dates indicated and the statement of operations, stockholders’ equity and cash flows of the Company and the Subsidiary for the periods specified; said financial statements have been prepared in conformity with U.S. generally accepted accounting principles (“GAAP”) applied on a consistent basis throughout the periods involved. The supporting schedules, if any, present fairly, in all material

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respects, in accordance with GAAP the information required to be stated therein. The selected financial data and the summary financial information, if any, and other financial data included or incorporated by reference in the Registration Statement, the General Disclosure Package and the Prospectus present fairly, in all material respects, the information shown therein and have been compiled on a basis consistent with that of the audited financial statements included therein. Except as included therein, no historical or pro forma financial statements or supporting schedules are required to be included or incorporated by reference in the Registration Statement, the General Disclosure Package or the Prospectus under the 1933 Act or the 1933 Act Regulations. All disclosures contained in the Registration Statement, the General Disclosure Package or the Prospectus, or incorporated by reference therein, regarding “non-GAAP financial measures” (as such term is defined by the rules and regulations of the Commission) comply with Regulation G of the 1934 Act, and Item 10 of Regulation S-K, to the extent applicable. The interactive data in eXtensible Business Reporting Language included or incorporated by reference in the Registration Statement, the General Disclosure Package and the Prospectus 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.

(ix) Compliance with the Sarbanes-Oxley Act of 2002. The Company is and has been in compliance with all provisions of the Sarbanes-Oxley Act of 2002 and the rules and regulations promulgated thereunder (collectively, the “Sarbanes-Oxley Act”) applicable to the Company at all times (taking into account all exemptions and phase-in periods provided under the Jumpstart Our Business Startups Act and otherwise under applicable law).

(x) No Material Adverse Change in Business. Since the respective dates as of which information is given in the Registration Statement, the General Disclosure Package or the Prospectus, (A) there has been no material adverse change in the condition, financial or otherwise, or in the earnings, business affairs or business prospects of the Company and the Subsidiary, considered as one enterprise, whether or not arising in the ordinary course of business (a “Material Adverse Effect”), (B) there have been no transactions entered into by the Company or the Subsidiary, other than those in the ordinary course of business, which are material with respect to the Company and the Subsidiary, considered as one enterprise, (C) there have been no material liabilities or obligations, direct or contingent, entered into by the Company or the Subsidiary and (D) there has been no dividend or distribution of any kind declared, paid or made by the Company on any class of its capital stock.

(xi) Good Standing of the Company. The Company has been duly organized and is validly existing as a corporation in good standing under the laws of the State of Delaware and has corporate power and authority to own, lease and operate its properties and to conduct its business as described in the Registration Statement, the General Disclosure Package and the Prospectus and to enter into and perform its obligations under this Agreement. The Company is duly qualified as a foreign corporation to transact business and is in good standing in each other jurisdiction in which such qualification is required, whether by reason of the ownership or leasing of property or the conduct of business, except where the failure to be so qualified or to be in good standing would not, individually or in the aggregate, result in a Material Adverse Effect.

(xii) Good Standing of the Company’s Subsidiaries. Trevi Therapeutics, Limited, a private limited company incorporated under the laws of England and Wales and the wholly owned subsidiary of the Company (the “Subsidiary”), has been duly organized and is validly existing in good standing under the laws of the jurisdiction of its incorporation or organization, has corporate or similar power and authority to own, lease and operate its properties and to conduct its business as described in the Registration Statement, the General Disclosure Package and the Prospectus. The

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Subsidiary is duly qualified to transact business and is in good standing in each jurisdiction in which such qualification is required, whether by reason of the ownership or leasing of property or the conduct of business, except where the failure to so qualify or to be in good standing would not, individually or in the aggregate, result in a Material Adverse Effect. All of the issued and outstanding capital stock of the Subsidiary has been duly authorized and validly issued, is fully paid and non-assessable and is owned by the Company directly, free and clear of any security interest, mortgage, pledge, lien, encumbrance, claim or equity. None of the outstanding shares of capital stock of the Subsidiary was issued in violation of the preemptive or similar rights of any securityholder of the Subsidiary. The Subsidiary is the only subsidiary of the Company.

(xiii) Capitalization. The authorized, issued and outstanding shares of capital stock of the Company are as set forth in the Registration Statement, the General Disclosure Package and the Prospectus (except for subsequent issuances, if any, (A) pursuant to this Agreement, (B) pursuant to reservations, agreements or employee benefit plans referred to in the Registration Statement, the General Disclosure Package and the Prospectus or (C) pursuant to the conversion of convertible securities or exercise of options referred to in the Registration Statement, the General Disclosure Package and the Prospectus). All of the outstanding shares of capital stock of the Company have been duly authorized and are validly issued, fully paid and non-assessable. None of the outstanding shares of capital stock of the Company was issued in violation of the preemptive or other similar rights of any securityholder of the Company.

(xiv) Authorization of Agreement. This Agreement has been duly authorized, executed and delivered by the Company.

(xv) Authorization and Description of Shares. The Shares to be purchased by the Underwriters from the Company have been duly authorized for issuance and sale to the Underwriters pursuant to this Agreement and, when issued and delivered by the Company pursuant to this Agreement against payment of the consideration set forth herein, will be validly issued and fully paid and non-assessable and will conform in all material respects to the description thereof contained in the Registration Statement, the General Disclosure Package and the Prospectus. The Common Stock conforms, in all material respects, to all statements relating thereto contained in the Registration Statement, the General Disclosure Package and the Prospectus and such description conforms, in all material respects, to the rights set forth in the instruments defining the same. The issuance and sale of the Shares as contemplated hereby is not subject to any preemptive or other similar rights of any securityholder of the Company. No holder of Shares will be subject to personal liability by reason of being such a holder.

(xvi) Registration Rights. There are no persons with registration rights or other similar rights to have any securities registered for sale pursuant to the Registration Statement or otherwise registered for sale or sold by the Company under the 1933 Act pursuant to this Agreement, other than those rights that have been disclosed in the Registration Statement, the General Disclosure Package and the Prospectus and have been duly waived.

(xvii) Absence of Violations, Defaults and Conflicts. Neither the Company nor the Subsidiary is (A) in violation of its charter, by-laws or similar organizational document, (B) in default in the performance or observance of any obligation, agreement, covenant or condition contained in any contract, indenture, mortgage, deed of trust, loan or credit agreement, note, lease or other agreement or instrument to which the Company or the Subsidiary is a party or by which either of them may be bound or to which any of the properties or assets of the Company or the Subsidiary is subject (collectively, “Agreements and Instruments”), except for such defaults that would not, individually or in the aggregate, result in a Material Adverse Effect, or (C) in violation

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of any law, statute, rule, regulation, judgment, order, writ or decree of any arbitrator, court, governmental body, regulatory body, administrative agency or other authority, body or agency having jurisdiction over the Company or the Subsidiary or any of their respective properties, assets or operations (each, a “Governmental Entity”), except for such violations that would not, individually or in the aggregate, result in a Material Adverse Effect. The execution, delivery and performance of this Agreement, the consummation of the transactions contemplated herein and in the Registration Statement, the General Disclosure Package and the Prospectus (including the issuance and sale of the Shares and the use of the proceeds from the sale of the Shares as described therein under the caption “Use of Proceeds”) and compliance by the Company with its obligations hereunder have been duly authorized by all necessary corporate action and do not and will not, whether with or without the giving of notice or passage of time or both, conflict with or constitute a breach of, or default or Repayment Event (as defined below) under, or result in the creation or imposition of any lien, charge or encumbrance upon any properties or assets of the Company or the Subsidiary pursuant to, the Agreements and Instruments (except for such conflicts, breaches, defaults or Repayment Events or liens, charges or encumbrances that would not, singly or in the aggregate, result in a Material Adverse Effect), nor will such action result in any violation of the provisions of the charter, by-laws or similar organizational document of the Company or the Subsidiary or any law, statute, rule, regulation, judgment, order, writ or decree of any Governmental Entity. As used herein, a “Repayment Event” means any event or condition which gives the holder of any note, debenture or other evidence of indebtedness (or any person acting on such holder’s behalf) the right to require the repurchase, redemption or repayment of all or a portion of such indebtedness by the Company or the Subsidiary.

(xviii) Nasdaq and Listing Matters. The Company is subject to and in compliance in all material respects with the reporting requirements of Section 13 or Section 15(d) of the 1934 Act. The Common Stock is registered pursuant to Section 12(b) of the 1934 Act and is listed on Nasdaq, and the Company has taken no action designed to, or reasonably likely to have the effect of, terminating the registration of the Common Stock under the 1934 Act or delisting the Common Stock from Nasdaq, nor has the Company received any notification that the Commission or Nasdaq is contemplating terminating such registration or listing. The Company is in compliance with the current listing standards of Nasdaq.

(xix) Absence of Labor Dispute. No labor dispute with the employees of the Company or the Subsidiary exists or, to the knowledge of the Company, is imminent, and the Company is not aware of any existing or imminent labor disturbance by the employees of any of its or the Subsidiary’s principal suppliers, manufacturers, customers or contractors, which, in each case, would, individually or in the aggregate, result in a Material Adverse Effect.

(xx) Absence of Proceedings. There is no action, suit, proceeding, inquiry or investigation before or brought by any Governmental Entity (including, without limitation, any action, suit proceeding, inquiry or investigation before or brought by the U.S. Food and Drug Administration (the “FDA”) or the European Medicines Agency (the “EMA”)) now pending or, to the knowledge of the Company, threatened, against or affecting the Company or the Subsidiary, which would reasonably be expected to materially and adversely affect their respective properties or assets or the consummation of the transactions contemplated in this Agreement or the performance by the Company of its obligations hereunder; and the aggregate of all pending legal or governmental proceedings to which the Company or the Subsidiary is a party or of which any of their respective properties or assets is the subject which are not described in the Registration Statement, the General Disclosure Package and the Prospectus, including ordinary routine litigation incidental to the business, would not, individually or in the aggregate, result in a Material Adverse Effect.

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(xxi) Accuracy of Exhibits. There are no contracts or documents which are required to be described in the Registration Statement, the General Disclosure Package or the Prospectus or to be filed as exhibits to the Registration Statement which have not been so described and filed as required.

(xxii) Absence of Further Requirements. No filing with, or authorization, approval, consent, license, order, registration, qualification or decree of, any Governmental Entity is necessary or required for the performance by the Company of its obligations hereunder, in connection with the offering, issuance or sale of the Shares hereunder, or the consummation of the transactions contemplated by this Agreement, except such as have been already obtained or as may be required under the 1933 Act, the 1933 Act Regulations, the rules of the Nasdaq Stock Market LLC, state securities laws or the rules of the Financial Industry Regulatory Authority, Inc. (“FINRA”).

(xxiii) Possession of Licenses and Permits. The Company and the Subsidiary possess such permits, licenses, approvals, consents and other authorizations (collectively, “Governmental Licenses”) issued by the appropriate Governmental Entities necessary to conduct the business now operated by them (including, without limitation, all such permits, licenses, approvals, consents and other authorizations required by the FDA, the EMA, or any other federal, state, local or foreign agencies or bodies engaged in the regulation of clinical or preclinical studies, pharmaceuticals, biologics, biohazardous substances or activities related to the business now operated by the Company and the Subsidiary), except where the failure so to possess would not, individually or in the aggregate, result in a Material Adverse Effect. The Company and the Subsidiary are in compliance in all material respects with the terms and conditions of all Governmental Licenses. The Company has fulfilled and performed all of its material obligations with respect to the Governmental Licenses and, to the knowledge of the Company, no event has occurred which allows, or after notice or lapse of time would allow, revocation or termination thereof or results in any other material impairment of the rights of the Company as a holder of any permit. All of the Governmental Licenses are valid and in full force and effect, except where the invalidity of such Governmental Licenses or the failure of such Governmental Licenses to be in full force and effect would not, individually or in the aggregate, result in a Material Adverse Effect. Neither the Company nor the Subsidiary has received any notice of proceedings relating to the revocation or modification of any Governmental Licenses which, if the subject of an unfavorable decision, ruling or finding, would, individually or in the aggregate, result in a Material Adverse Effect.

(xxiv) Title to Property. The Company and the Subsidiary have good and marketable title to all real property owned by them and good title to all other properties owned by them (excluding, for the purpose of this Section 1(a)(xxiv), Intellectual Property (as defined below), which is addressed below in Section 1(a)(xxv)), in each case, free and clear of all mortgages, pledges, liens, security interests, claims, restrictions or encumbrances of any kind except such as do not, individually or in the aggregate, materially affect the value of such property and do not materially interfere with the use made and proposed to be made of such property by the Company or the Subsidiary; and all of the leases and subleases material to the business of the Company and the Subsidiary, considered as one enterprise, and under which the Company or the Subsidiary holds properties described in the Registration Statement, the General Disclosure Package or the Prospectus, are in full force and effect, and neither the Company nor the Subsidiary has received any notice of any material claim of any sort that has been asserted by anyone adverse to the rights of the Company or the Subsidiary under any of the leases or subleases mentioned above, or affecting or questioning the rights of the Company or the Subsidiary to the continued possession of the leased or subleased premises under any such lease or sublease.

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(xxv) Title to Intellectual Property. To the knowledge of the Company, the Company and the Subsidiary own or have obtained valid, binding and enforceable licenses under, or otherwise have the right to use, the patents, patent applications, inventions, copyrights, know-how, trade secrets and other unpatented and/or unpatentable proprietary or confidential information, systems or procedures, trademarks, service marks, trade names or other intellectual property necessary for, or used in the conduct, or the proposed conduct, of the business of the Company in the manner described in the Registration Statement, the General Disclosure Package and the Prospectus (collectively, the “Intellectual Property”); to the knowledge of the Company, the patents, trademarks, and registered copyrights, if any, included within the Intellectual Property are valid, enforceable, and subsisting; and none of the technology employed by the Company has been obtained or is being used by the Company in material violation of any contractual obligation binding on the Company, or, to the Company’s knowledge, upon any of its officers, directors or employees or otherwise in violation of the rights of any persons. Except as disclosed in the Registration Statement, the General Disclosure Package and the Prospectus, the Company is not obligated to pay a material royalty, grant a license to, or provide other material consideration to any third party in connection with the Intellectual Property. To the Company’s knowledge, (i) (i) there are no third parties who have rights to any material Intellectual Property that is owned by or exclusively licensed to the Company, (1) except for customary reversionary rights of third-party licensors with respect to Intellectual Property that is disclosed in the Registration Statement, the General Disclosure Package and the Prospectus as licensed to the Company or the Subsidiary, (2) except for rights of third parties under any Intellectual Property licensed to the Company or the Subsidiary that is disclosed in the Registration Statement, the General Disclosure Package and the Prospectus, (3) except for any licenses or sublicenses granted by the Company in the ordinary course in connection with the conduct of the business of the Company, and (4) except for the ownership rights of any co-owner of any patent constituting Intellectual Property who is listed on the records of the U.S. Patent and Trademark Office (the “USPTO”) and any co-owner of any patent application constituting Intellectual Property who is named in such patent application, and, to the knowledge of the Company, no third party has any ownership right in or to any Intellectual Property in any field of use that is exclusively licensed to the Company or the Subsidiary, other than any licensor to the Company of such Intellectual Property; and (ii) there is no infringement by third parties of any Intellectual Property. There is no pending or, to the knowledge of the Company, threatened action, suit, proceeding or claim by others (x) challenging the Company’s rights in or to any Intellectual Property, and the Company is unaware of any facts which would form a reasonable basis for any such action, suit, proceeding or claim; (y) challenging the validity or scope of any Intellectual Property that is (I) owned by the Company or the Subsidiary or (II) exclusively licensed to the Company or the Subsidiary, and the Company is unaware of any facts which would form a reasonable basis for any such action, suit, proceeding or claim; or (z) asserting that the Company or the Subsidiary infringes or otherwise violates, or would, upon the commercialization of any product or service described in the Registration Statement, the General Disclosure Package and the Prospectus as under development, infringe or violate, any patent, trademark, trade name, service name, copyright, trade secret or other proprietary rights of others, and the Company is unaware of any facts which would form a reasonable basis for any such action, suit, proceeding or claim. The Company is in compliance with the terms of each agreement pursuant to which Intellectual Property has been licensed to the Company, and all such agreements are in full force and effect, except where the failure so to comply or for such agreements to be in full force and effect would not, individually or in the aggregate, result in a Material Adverse Effect.

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(xxvi) Patents and Patent Applications. All patents and patent applications owned by or licensed to the Company or under which the Company has rights have, to the knowledge of the Company, been duly and properly filed and maintained; to the knowledge of the Company, the parties prosecuting such patent applications have complied with their duty of candor and disclosure to the USPTO in connection with such applications; and the Company is not aware of any facts required to be disclosed to the USPTO that were not disclosed to the USPTO and which would preclude the grant of a patent in connection with any such application or would reasonably be expected to form the basis of a finding of invalidity with respect to any patents that have issued with respect to such applications. To the Company’s knowledge, all patents and patent applications owned by the Company and filed with the USPTO or any foreign or international patent authority (the “Company Patent Rights”) and all patents and patent applications in-licensed by the Company and filed with the USPTO or any foreign or international patent authority (the “In-licensed Patent Rights”) have been duly and properly filed; the Company has complied with its duty of candor and disclosure to the USPTO for the Company Patent Rights and, to the Company’s knowledge, the licensors of the In-licensed Patent Rights have complied with their duty of candor and disclosure to the USPTO for the In-licensed Patent Rights.

(xxvii) FDA Compliance. Except as would not, individually or in the aggregate, result in a Material Adverse Effect, the Company: (i) is and at all times has been in compliance with all statutes, rules and regulations of the FDA and other comparable Governmental Entities applicable to the ownership, testing, development, manufacture, packaging, processing, use, distribution, marketing, labeling, promotion, sale, offer for sale, storage, import, export or disposal of any product under development, manufactured or distributed by the Company (“Applicable Laws”); (ii) has not received any FDA Form 483, notice of adverse finding, warning letter, untitled letter or other correspondence or written notice from the FDA or any Governmental Entity alleging or asserting noncompliance with any Applicable Laws or any licenses, certificates, approvals, clearances, exemptions, authorizations, permits and supplements or amendments thereto required by any such Applicable Laws (“Authorizations”); (iii) possesses all Authorizations and such Authorizations are valid and in full force and effect and the Company is not in violation of any term of any such Authorizations; (iv) has not received notice of any claim, action, suit, proceeding, hearing, enforcement, investigation, arbitration or other action from the FDA or any Governmental Entity or third party alleging that any product, operation or activity is in violation of any Applicable Laws or Authorizations and, to the Company’s knowledge, neither the FDA nor any Governmental Entity or third party is considering any such claim, litigation, arbitration, action, suit, investigation or proceeding; (v) has not received notice that the FDA or any Governmental Entity has taken, is taking or intends to take action to limit, suspend, modify or revoke any Authorizations and, to the Company’s knowledge, neither the FDA nor any Governmental Entity is considering such action; and (vi) has filed, obtained, maintained or submitted all reports, documents, forms, notices, applications, records, claims, submissions and supplements or amendments as required by any Applicable Laws or Authorizations and that all such reports, documents, forms, notices, applications, records, claims, submissions and supplements or amendments were complete and correct on the date filed (or were corrected or supplemented by a subsequent submission).

(xxviii) Compliance with Health Care Laws. The Company and the Subsidiary have operated and currently are in compliance with all applicable health care laws, rules and regulations (except where such failure to operate or non-compliance would not, individually or in the aggregate, result in a Material Adverse Effect), including, without limitation, (i) the Federal, Food, Drug, and Cosmetic Act (21 U.S.C. §§ 301 et seq.); (ii) all applicable federal, state, local and all applicable foreign healthcare related fraud and abuse laws, including, without limitation, the federal Anti-kickback Statute (42 U.S.C. § 1320a-7b(b)), the U.S. Physician Payments Sunshine Act (42 U.S.C. § 1320a-7h), the civil False Claims Act (31 U.S.C. §§ 3729 et seq.), the criminal False Claims Law (18 U.S.C. § 287), all criminal laws relating to healthcare fraud and abuse, including but not limited to 42 U.S.C. Section 1320a-7b(a), the exclusion laws (42 U.S.C. § 1320a-7), and the civil monetary penalties law (42 U.S.C. § 1320a-7a); (iii) U.S. Health Insurance Portability and Accountability Act of 1996 (“HIPAA”) (42 U.S.C. Section 1320d et seq.), as amended by the

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Health Information Technology for Economic Clinical Health Act (42 U.S.C. Section 17921 et seq.); (iv) the regulations promulgated pursuant to such laws; and (v) any other similar local, state, federal or foreign laws (collectively, the “Health Care Laws”). None of the Company, the Subsidiary or, to the knowledge of the Company, any of its officers, directors, employees or agents has engaged in activities which are, as applicable, cause for false claims liability, civil penalties, or mandatory or permissive exclusion from Medicare, Medicaid, or any other state or federal healthcare program. Neither the Company nor the Subsidiary has received written notice or other correspondence of any claim, action, suit, audit, survey, proceeding, hearing, enforcement, investigation, arbitration or other action from any court, arbitrator, governmental or regulatory authority or third party alleging that any product, operation or activity is in violation of any Health Care Laws, and, to the knowledge of the Company, no such claim, action, suit, proceeding, hearing, enforcement, investigation, arbitration or other action is threatened. Neither the Company nor the Subsidiary is a party to or has any ongoing reporting obligations pursuant to any corporate integrity agreement, deferred prosecution agreement, monitoring agreement, consent decree, settlement order, plan of correction or similar agreement imposed by any governmental or regulatory authority. Additionally, none of the Company, the Subsidiary or, to the knowledge of the Company, any of its officers, directors, employees or agents, has been excluded, suspended or debarred from participation in any U.S. state or federal health care program or human clinical research or, to the knowledge of the Company, is subject to a governmental inquiry, investigation, proceeding, or other similar action that could reasonably be expected to result in debarment, suspension or exclusion.

(xxix) Environmental Laws. Except as would not, individually or in the aggregate, result in a Material Adverse Effect, (i) neither the Company nor the Subsidiary is in violation of any federal, state, local or foreign statute, law, rule, regulation, ordinance, code, policy or rule of common law or any judicial or administrative interpretation thereof, including any judicial or administrative order, consent, decree or judgment, relating to pollution or protection of human health, the environment (including, without limitation, ambient air, surface water, groundwater, land surface or subsurface strata) or wildlife, including, without limitation, laws and regulations relating to the release or threatened release of chemicals, pollutants, contaminants, wastes, toxic substances, hazardous substances, petroleum or petroleum products, asbestos-containing materials or mold (collectively, “Hazardous Materials”) or to the manufacture, processing, distribution, use, treatment, storage, disposal, transport or handling of Hazardous Materials (collectively, “Environmental Laws”); (ii) the Company and the Subsidiary have all permits, authorizations and approvals required under any applicable Environmental Laws and are each in compliance with their requirements; (iii) there are no pending or, to the knowledge of the Company, threatened administrative, regulatory or judicial actions, suits, demands, demand letters, claims, liens, notices of noncompliance or violation, investigation or proceedings relating to any Environmental Law against the Company or the Subsidiary; and (iv) there are no events or circumstances that would reasonably be expected to form the basis of an order for clean-up or remediation, or an action, suit or proceeding by any private party or Governmental Entity, against or affecting the Company or the Subsidiary relating to Hazardous Materials or any Environmental Laws.

(xxx) Accounting Controls and Disclosure Controls. The Company and the Subsidiary maintain effective internal control over financial reporting (as defined under Rule 13a-15 and 15d-15 under the 1934 Act) and a system of internal accounting controls sufficient to provide reasonable assurances that (i) transactions are executed in accordance with management’s general or specific authorization; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with GAAP and to maintain accountability for assets; (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 existing assets at reasonable intervals and

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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 General Disclosure Package and the Prospectus fairly presents the information called for in all material respects and is prepared in accordance with the Commission’s rules and guidelines applicable thereto. The Company and the Subsidiary have established and maintain disclosure controls and procedures (as defined in Rules 13a-15 and 15d-15 under the 1934 Act), which (i) are designed to ensure that information relating to the Company, including the Subsidiary, is made known to the Company’s principal executive officer and its principal financial officer by others within those entities, particularly during the periods in which the periodic reports required under the 1934 Act are being prepared; (ii) have been evaluated by management of the Company for effectiveness as of the end of the Company’s most recent fiscal quarter; and (iii) are effective in all material respects to perform the functions for which they were established. Since the end of the Company’s most recent audited fiscal year, there has been (x) no material weakness in the Company’s internal control over financial reporting (whether or not remediated) and (y) no change in the Company’s internal control over financial reporting that has materially adversely affected, or is reasonably likely to materially adversely affect, the Company’s internal control over financial reporting.

(xxxi) Tests and Preclinical and Clinical Trials. The studies, tests and preclinical and clinical trials conducted by or, to the knowledge of the Company, on behalf of the Company (the “Company Trials”) that are described in the Registration Statement, the General Disclosure Package and the Prospectus were and, if still ongoing, are being conducted in all material respects in accordance with the protocols submitted to the FDA, the EMA or any foreign governmental body exercising comparable authority, and procedures and controls pursuant to, where applicable, accepted professional and scientific standards, and all Authorizations and Applicable Laws, including, without limitation, the Federal Food, Drug, and Cosmetic Act and the rules and regulations promulgated thereunder; the descriptions of the Company Trials and the results thereof, contained in the Registration Statement, the General Disclosure Package and the Prospectus are, to the knowledge of the Company, accurate and complete in all material respects and fairly present the data derived from such Company Trials; the Company is not aware of any studies, tests or trials, the results of which the Company believes reasonably call into question the results of the Company Trials described or referred to in the Registration Statement, the General Disclosure Package and the Prospectus when viewed in the context in which such results are described and the clinical state of development; and the Company has not received any correspondence or written notices from the FDA or any Governmental Entity requiring the termination or suspension of any Company Trials, other than ordinary course communications with respect to modifications in connection with the design and implementation of such trials.

(xxxii) Payment of Taxes. All United States federal income tax returns of the Company and the Subsidiary required by law to be filed have been filed and all taxes shown by such returns or otherwise assessed, which are due and payable, have been paid, except assessments against which appeals have been or will be promptly taken and as to which adequate reserves have been established by the Company. The United States federal income tax returns of the Company through the fiscal year ended December 31, 2023 have been filed and no assessment in connection therewith has been made against the Company. The Company and the Subsidiary have filed all other tax returns that are required to have been filed by them pursuant to applicable foreign, state, local or other law, and have paid all taxes due pursuant to such returns or pursuant to any assessment received by the Company or the Subsidiary, except for such taxes, if any, as are being contested in good faith and as to which adequate reserves have been established by the Company and except insofar as the failure to file such returns would not, individually or in the aggregate, result in a Material Adverse Effect. The charges, accruals and reserves on the books of the Company in respect of any income and corporation tax liability for any years not finally determined are, in conformity with GAAP, adequate to meet any assessments or re-assessments for additional income tax for any years not finally determined, except to the extent of any inadequacy that would not, individually or in the aggregate, result in a Material Adverse Effect.

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(xxxiii) Insurance. The Company and the Subsidiary carry or are entitled to the benefits of insurance, with financially sound and reputable insurers, in such amounts and covering such risks as is generally maintained by companies of established repute engaged in the same or similar business, and all such insurance is in full force and effect. The Company has no reason to believe that it or the Subsidiary will not be able to (i) renew their existing insurance coverage as and when such policies expire or (ii) obtain comparable coverage from similar institutions as may be necessary or appropriate to conduct their business as now conducted and which coverage is not at a materially higher cost. Neither of the Company nor the Subsidiary has been denied any insurance coverage which it has sought or for which it has applied.

(xxxiv) Investment Company Act. The Company is not required, and upon the issuance and sale of the Shares as herein contemplated and the application of the net proceeds therefrom as described in the Registration Statement, the General Disclosure Package and the Prospectus will not be required, to register as an “investment company” under the Investment Company Act of 1940, as amended (the “1940 Act”).

(xxxv) Absence of Manipulation. Neither the Company nor any affiliate of the Company has taken, nor will the Company or any affiliate take, directly or indirectly, any action which is designed, or would reasonably be expected, to cause or result in, or which constitutes, the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Shares or to result in a violation of Regulation M under the 1934 Act.

(xxxvi) Foreign Corrupt Practices Act. None of the Company, the Subsidiary, any director or officer of the Company or the Subsidiary, or, to the Company’s knowledge, any agent, employee or affiliate of the Company or the Subsidiary or any other person acting on behalf of the Company or the Subsidiary is aware of or has taken any action, directly or indirectly, that would result in a violation by such persons of the Foreign Corrupt Practices Act of 1977, as amended, and the rules and regulations thereunder (the “FCPA”), including, without limitation, making use of the mails or any means or instrumentality of interstate commerce corruptly in furtherance of an offer, payment, promise to pay or authorization of the payment of any money, or other property, gift, promise to give, or authorization of the giving of anything of value to any “foreign official” (as such term is defined in the FCPA) or any foreign political party or official thereof or any candidate for foreign political office, in contravention of the FCPA and the Company, the Subsidiary and, to the knowledge of the Company, its affiliates have conducted their businesses in compliance with the FCPA and have instituted and maintain policies and procedures designed to ensure, and which are reasonably expected to continue to ensure, continued compliance therewith.

(xxxvii) Money Laundering Laws. The operations of the Company and the Subsidiary are and have been conducted at all times in compliance with applicable financial recordkeeping and reporting requirements of the Currency and Foreign Transactions Reporting Act of 1970, as amended, the money laundering statutes of all applicable jurisdictions, the rules and regulations thereunder and any related or similar rules, regulations or guidelines, issued, administered or enforced by any Governmental Entity (collectively, the “Money Laundering Laws”); and no action, suit or proceeding by or before any Governmental Entity involving the Company or the Subsidiary with respect to the Money Laundering Laws is pending or, to the knowledge of the Company, threatened.

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(xxxviii) OFAC. None of the Company, the Subsidiary, any director or officer of the Company or Subsidiary, or, to the Company’s knowledge, any agent, employee, affiliate or representative of the Company or the Subsidiary is an individual or entity (“Person”) currently the subject or target of any sanctions administered or enforced by the United States government, including, without limitation, the U.S. Department of the Treasury’s Office of Foreign Assets Control, or the United Nations Security Council, the European Union, His Majesty’s Treasury or other relevant sanctions authority (collectively, “Sanctions”), nor is the Company located, organized or resident in a country or territory that is a subject of Sanctions; and the Company will not directly or indirectly use the proceeds of the sale of the Shares, or lend, contribute or otherwise make available such proceeds to the Subsidiary or to any joint venture partners or other Person to fund any activities of or business with any Person, or in any country or territory, that, at the time of such funding, is a subject of Sanctions or 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.

(xxxix) No Unlawful Contributions or Other Payments. None of the Company, the Subsidiary or any employee or agent of the Company or the Subsidiary has made any contribution or other payment to any official of, or candidate for, any federal, state or foreign office in violation of any law.

(xl) Lending Relationship. Except as disclosed in the Registration Statement, the General Disclosure Package and the Prospectus, the Company (i) does not have any material lending or other relationship with any banking or lending affiliate of any Underwriter and (ii) does not intend to use any of the proceeds from the sale of the Shares to repay any outstanding debt owed to any affiliate of any Underwriter.

(xli) Statistical and Market-Related Data. Any statistical and market-related data included in the Registration Statement, the General Disclosure Package or the Prospectus are based on or derived from sources that the Company believes, after reasonable inquiry, to be reliable and accurate and, to the extent required, the Company has obtained the written consent to the use of such data from such sources.

(xlii) Maintenance of Rating. The Company has no debt securities or preferred stock that is rated by any “nationally recognized statistical rating organization” (as that term is defined by the Commission for purposes of Rule 436(g)(2) under the 1933 Act).

(xliii) Privacy and Data Protection. The Company and the Subsidiary have operated their business in a manner compliant in all material respects with all United States federal, state and local and non-United States privacy, data security and data protection laws and regulations applicable to the Company’s collection, use, transfer, protection, disposal, disclosure, handling, storage and analysis of personal data. The Company and the Subsidiary have been and are in compliance in all material respects with internal policies and procedures designed to protect the integrity and security of the data collected, handled or stored in connection with their business; the Company and the Subsidiary have been and are in compliance in all material respects with internal policies and procedures designed to promote compliance with the Health Care Laws that govern privacy and data security and take and have taken reasonably appropriate steps designed to attain compliance with such policies and procedures. The Company and the Subsidiary have taken reasonable steps to maintain the confidentiality of the personally identifiable information, protected health information, consumer information and other confidential information of the Company, the Subsidiary and any third parties in their possession (“Sensitive Company Data”). The tangible or digital information technology systems (including computers, screens, servers, workstations,

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routers, hubs, switches, networks, data communications lines, technical data and hardware), software and telecommunications systems used or held for use by the Company and the Subsidiary (the “Company IT Assets”) are adequate and operational for, in accordance with their documentation and functional specifications, the business of the Company and the Subsidiary as now operated and as currently proposed to be conducted as described in the Registration Statement, the General Disclosure Package and the Prospectus. The Company and the Subsidiary have established commercially reasonable disaster recovery and security plans, procedures and facilities for the business consistent with industry standards and practices in all material respects, including, without limitation, for the Company IT Assets and data held or used by or for the Company and the Subsidiary. To the Company’s knowledge, after due inquiry, (i) the Company and the Subsidiary have not suffered or incurred any security breaches, compromises or incidents with respect to any Company IT Asset or Sensitive Company Data; and (ii) there has been no unauthorized or illegal use of or access to any Company IT Asset or Sensitive Company Data by any unauthorized third party. The Company and the Subsidiary have not been required to notify any individual of any information security breach, compromise or incident involving Sensitive Company Data.

(xliv) No Broker Fees. Except pursuant to this Agreement, there are no contracts, agreements or understandings between the Company and any person that would give rise to a valid claim against the Company or any Underwriter for a brokerage commission, finder’s fee or other like payment in connection with the offering of the Shares contemplated hereby.

(xlv) ERISA Compliance. The Company and the Subsidiary and any “employee benefit plan” (as defined under the Employee Retirement Income Security Act of 1974, as amended, and the regulations and published interpretations thereunder (collectively, “ERISA”)) established or maintained by the Company, the Subsidiary or their ERISA Affiliates (as defined below) are in compliance in all material respects with ERISA. “ERISA Affiliate” means, with respect to the Company or the Subsidiary, any member of any group of organizations described in Sections 414(b), (c), (m) or (o) of the Internal Revenue Code of 1986, as amended, and the regulations and published interpretations thereunder (the “Code”) of which the Company or the Subsidiary is a member. No “reportable event” (as defined under ERISA) has occurred or is reasonably expected to occur with respect to any “employee benefit plan” established or maintained by the Company, the Subsidiary or any of their ERISA Affiliates. No “employee benefit plan” established or maintained by the Company, the Subsidiary or any of their ERISA Affiliates, if such “employee benefit plan” were terminated, would have any “amount of unfunded benefit liabilities” (as defined under ERISA). Neither the Company, the Subsidiary nor any of their ERISA Affiliates has incurred or reasonably expects to incur any liability under (A) Title IV of ERISA with respect to termination of, or withdrawal from, any “employee benefit plan” or (B) Sections 412, 4971, 4975 or 4980B of the Code. Each employee benefit plan established or maintained by the Company, the Subsidiary or any of their ERISA Affiliates that is intended to be qualified under Section 401(a) of the Code is so qualified and nothing has occurred, whether by action or failure to act, which would cause the loss of such qualification.

(xlvi) Related-Party Transactions. There are no business relationships or related-party transactions involving the Company or the Subsidiary or any other person required to be described in the Registration Statement, the General Disclosure Package or the Prospectus that have not been described as required.

(xlvii) FINRA Matters. All of the information provided to the Underwriters or to counsel for the Underwriters by the Company, its counsel, its officers and directors and the holders of any securities (debt or equity) or options to acquire any securities of the Company in connection with the offering of the Shares is true, complete, correct and compliant in all material respects with FINRA’s rules, and any letters, filings or other supplemental information provided to FINRA pursuant to FINRA Rules or NASD Conduct Rules is true, complete and correct in all material respects.

(b) Officer’s Certificates. Any certificate signed by any officer of the Company or the Subsidiary delivered to the Representatives or to counsel for the Underwriters shall be deemed a representation and warranty by the Company to each Underwriter as to the matters covered thereby.

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SECTION 2. Sale and Delivery to Underwriters; Closing.

(a) Shares. On the basis of the representations and warranties herein contained and subject to the terms and conditions herein set forth, the Company agrees to sell to each Underwriter, severally and not jointly, and each Underwriter, severally and not jointly agrees to purchase from the Company, at the price per Share set forth in Schedule A, that number of Shares set forth in Schedule A opposite the name of such Underwriter, plus any additional number of Shares which such Underwriter may become obligated to purchase pursuant to the provisions of Section 10 hereof, subject, in each case, to such adjustments among the Underwriters as the Representatives in their sole discretion shall make to eliminate any sales or purchases of fractional shares.

(b) [Reserved].

(c) Payment. Payment of the purchase price for, and delivery of certificates or security entitlements for, the Shares shall be made through the offices of Covington & Burling LLP, or at such other place as shall be agreed upon by the Representatives and the Company, at 10:00 A.M. (New York City time) on the first (second, if the pricing occurs after 4:30 P.M. (New York City time) on any given day) business day after the date hereof, or such other time not later than ten business days after such date as shall be agreed upon by the Representatives and the Company (such time and date of payment and delivery being herein called “Closing Time”). Delivery of the Shares at the Closing Time shall be made through the facilities of The Depository Trust Company unless the Representatives shall otherwise instruct.

Payment shall be made to the Company by wire transfer of immediately available funds to a bank account designated by the Company, against delivery to the Representatives for the respective accounts of the Underwriters of certificates or security entitlements for the Shares to be purchased by them. It is understood that each Underwriter has authorized the Representatives, for their accounts, to accept delivery of, receipt for, and make payment of the purchase price for, the Shares which it has agreed to purchase. Each of Leerink Partners, Stifel and Oppenheimer, individually and not as Representatives of the Underwriters, may (but shall not be obligated to) make payment of the purchase price for the Shares, if any, to be purchased by any Underwriter whose funds have not been received by the Closing Time, but such payment shall not relieve such Underwriter from its obligations hereunder.

SECTION 3. Covenants of the Company. The Company covenants with each Underwriter as follows:

(a) Compliance with Securities Regulations and Commission Requests. The Company, subject to Section 3(b), will comply with the requirements of Rule 430B, and will notify the Representatives as soon as practicable, and confirm the notice in writing, (i) when any post-effective amendment to the Registration Statement shall become effective or any amendment or supplement to the Prospectus shall have been filed, (ii) of the receipt of any comments from the Commission, (iii) of any request by the Commission for any amendment to the Registration Statement or any amendment or supplement to the Prospectus (including any document incorporated by reference therein) or for additional information, (iv) of

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the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement or any post-effective amendment or of any order preventing or suspending the use of any preliminary prospectus or the Prospectus, or of the suspension of the qualification of the Shares for offering or sale in any jurisdiction, or of the initiation or threatening of any proceedings for any of such purposes or of any examination pursuant to Section 8(d) or 8(e) of the 1933 Act concerning the Registration Statement and (v) if the Company becomes the subject of a proceeding under Section 8A of the 1933 Act in connection with the offering of the Shares. The Company will effect all filings required under Rule 424(b), in the manner and within the time period required by Rule 424(b) (without reliance on Rule 424(b)(8)), and will take such steps as it deems necessary to ascertain promptly whether the form of prospectus transmitted for filing under Rule 424(b) was received for filing by the Commission and, in the event that it was not, it will promptly file such prospectus. The Company will make every reasonable effort to prevent the issuance of any stop order, prevention or suspension and, if any such order is issued, to obtain the lifting thereof at the earliest possible moment.

(b) Continued Compliance with Securities Laws. The Company will comply with the 1933 Act, the 1933 Act Regulations, the 1934 Act and the 1934 Act Regulations so as to permit the completion of the distribution of the Shares as contemplated in this Agreement and in the Registration Statement, the General Disclosure Package and the Prospectus. If at any time when a prospectus relating to the Shares is (or, but for the exception afforded by Rule 172 of the 1933 Act Regulations (“Rule 172”), would be) required by the 1933 Act to be delivered in connection with sales of the Shares, any event shall occur or condition shall exist as a result of which it is necessary, in the opinion of counsel for the Underwriters or for the Company, to (i) amend the Registration Statement in order that the Registration Statement will not include an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading, (ii) amend or supplement the General Disclosure Package or the Prospectus in order that the General Disclosure Package or the Prospectus, as the case may be, will not include any untrue statement of a material fact or omit to state a material fact necessary in order to make the statements therein not misleading in the light of the circumstances existing at the time it is delivered to a purchaser or (iii) amend the Registration Statement or amend or supplement the General Disclosure Package or the Prospectus, as the case may be, in order to comply with the requirements of the 1933 Act or the 1933 Act Regulations, the Company will promptly (A) give the Representatives notice of such event, (B) prepare any amendment or supplement as may be necessary to correct such statement or omission or to make the Registration Statement, the General Disclosure Package or the Prospectus comply with such requirements and, a reasonable amount of time prior to any proposed filing or use, furnish the Representatives with copies of any such amendment or supplement and (C) file with the Commission any such amendment or supplement; provided that the Company shall not file or use any such amendment or supplement to which the Representatives or counsel for the Underwriters shall reasonably object. The Company will furnish to the Underwriters such number of copies of such amendment or supplement as the Underwriters may reasonably request. The Company has given the Representatives notice of any filings made pursuant to the 1934 Act or the 1934 Act Regulations within 48 hours prior to the Applicable Time; the Company will give the Representatives notice of its intention to make any such filing from the Applicable Time to the Closing Time and will furnish the Representatives with copies of any such documents a reasonable amount of time prior to such proposed filing, as the case may be, and will not file or use any such document to which the Representatives or counsel for the Underwriters shall object.

(c) Delivery of Registration Statements. The Company has furnished or will deliver to the Representatives and counsel for the Underwriters, without charge, signed copies of the Registration Statement as originally filed and each amendment thereto (including exhibits filed therewith or incorporated by reference therein and documents incorporated or deemed incorporated by reference therein) and signed copies of all consents and certificates of experts, and will also deliver to the Representatives, without charge, a conformed copy of the Registration Statement as originally filed and each amendment thereto (without exhibits) for each of the Underwriters. The copies of the Registration Statement and each amendment thereto furnished to the Underwriters will be identical to the electronically transmitted copies thereof filed with the Commission pursuant to EDGAR, except to the extent permitted by Regulation S-T.

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(d) Delivery of Prospectuses. The Company has delivered to each Underwriter, without charge, as many copies of each preliminary prospectus as such Underwriter reasonably requested, and the Company hereby consents to the use of such copies for purposes permitted by the 1933 Act. The Company will furnish to each Underwriter, without charge, during the period when a prospectus relating to the Shares is (or, but for the exception afforded by Rule 172, would be) required to be delivered under the 1933 Act, such number of copies of the Prospectus (as amended or supplemented) as such Underwriter may reasonably request. The Prospectus and any amendments or supplements thereto furnished to the Underwriters will be identical to the electronically transmitted copies thereof filed with the Commission pursuant to EDGAR, except to the extent permitted by Regulation S-T.

(e) Blue Sky Qualifications. The Company will use its best efforts, in cooperation with the Underwriters, to qualify the Shares for offering and sale under the applicable securities laws of such states and other jurisdictions (domestic or foreign) as the Representatives may designate and to maintain such qualifications in effect so long as required to complete the distribution of the Shares; provided, however, that the Company shall not be obligated to file any general consent to service of process or to qualify as a foreign corporation or as a dealer in securities in any jurisdiction in which it is not so qualified or to subject itself to taxation in respect of doing business in any jurisdiction in which it is not otherwise so subject.

(f) Rule 158. The Company will timely file such reports pursuant to the 1934 Act as are necessary in order to make generally available to its securityholders as soon as practicable an earning statement for the purposes of, and to provide to the Underwriters the benefits contemplated by, the last paragraph of Section 11(a) of the 1933 Act.

(g) Use of Proceeds. The Company will use the net proceeds received by it from the sale of the Shares in all material respects in the manner specified in the Registration Statement, the General Disclosure Package and the Prospectus under the heading “Use of Proceeds.”

(h) Listing. The Company will use its reasonable best efforts to effect and maintain the listing of the Shares on the Nasdaq Global Market.

(i) Restriction on Sale of Securities. During a period of 45 days from the date of the Prospectus, the Company will not, without the prior written consent of Leerink Partners, (i) directly or indirectly, 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 any shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock or file or confidentially submit any registration statement under the 1933 Act with respect to any of the foregoing, (ii) enter into any swap or any other agreement or any transaction that transfers, in whole or in part, directly or indirectly, the economic consequence of ownership of the Common Stock, whether any such swap or transaction described in clause (i) or (ii) above is to be settled by delivery of Common Stock or such other securities, in cash or otherwise or (iii) publicly announce an intention to effect any such swap, agreement or other transaction described in clauses (i) and (ii). The foregoing sentence shall not apply to (A) the Shares to be sold hereunder; (B) any shares of Common Stock issued by the Company upon the exercise of an option or warrant or the conversion of a convertible security outstanding on the date hereof and referred to in the Registration Statement, the General Disclosure Package and the Prospectus; (C) any shares of Common Stock issued or options to purchase Common Stock granted pursuant to existing employee benefit plans of the Company referred to in the Registration Statement, the General Disclosure Package and the Prospectus; (D) any shares of Common Stock issued pursuant to any existing non-employee director stock plan or dividend reinvestment plan referred to in the Registration Statement, the

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General Disclosure Package and the Prospectus; (E) the filing by the Company of any registration statement on Form S-8 or a successor form thereto or (F) any shares of Common Stock or other securities issued in connection with a transaction that includes a commercial relationship (including joint ventures, collaboration agreements, intellectual property license agreements and strategic acquisitions), provided that the aggregate number of shares issued pursuant to this clause (F) shall not exceed 5% of the total number of shares of Common Stock issued and outstanding immediately following the completion of the transactions contemplated by this Agreement.

(j) Reporting Requirements. The Company, during the period when a Prospectus relating to the Shares is (or, but for the exception afforded by Rule 172, would be) required to be delivered under the 1933 Act, will file all documents required to be filed with the Commission pursuant to the 1934 Act within the time periods required by the 1934 Act and 1934 Act Regulations. Additionally, the Company shall report the use of proceeds from the issuance of the Shares as may be required under Rule 463 under the 1933 Act.

(k) Issuer Free Writing Prospectuses. The Company agrees that, unless it obtains the prior written consent of the Representatives, it will not make any offer relating to the Shares that would constitute an Issuer Free Writing Prospectus or that would otherwise constitute a “free writing prospectus,” or a portion thereof, required to be filed by the Company with the Commission or retained by the Company under Rule 433; provided that the Representatives will be deemed to have consented to the Issuer Free Writing Prospectuses listed on Schedule B-2 hereto and any “road show that is a written communication” within the meaning of Rule 433(d)(8)(i) that has been reviewed by the Representatives. The Company represents that it has treated or agrees that it will treat each such free writing prospectus consented to, or deemed consented to, by the Representatives as an “issuer free writing prospectus,” as defined in Rule 433, and that it has complied and will comply with the applicable requirements of Rule 433 with respect thereto, including timely filing with the Commission where required, legending and record keeping. If at any time following issuance of an Issuer Free Writing Prospectus there occurred or occurs an event or development as a result of which such Issuer Free Writing Prospectus conflicted or would conflict with the information contained in the Registration Statement, any preliminary prospectus or the Prospectus or included or would include an untrue statement of a material fact or omitted or would omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances existing at that subsequent time, not misleading, the Company will promptly notify the Representatives and will promptly amend or supplement, at its own expense, such Issuer Free Writing Prospectus to eliminate or correct such conflict, untrue statement or omission.

(l) Testing-the-Waters Materials. If at any time following the distribution of any Written Testing-the-Waters Communication there occurred or occurs an event or development as a result of which such Written Testing-the-Waters Communication included or would include an untrue statement of a material fact or omitted or would omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances existing at that subsequent time, not misleading, the Company will promptly notify the Representatives and will promptly amend or supplement, at its own expense, such Written Testing-the-Waters Communication to eliminate or correct such untrue statement or omission.

(m) Emerging Growth Company Status. The Company will promptly notify the Representatives if the Company ceases to be an Emerging Growth Company at any time prior to the completion of the distribution of the Shares within the meaning of the 1933 Act.

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SECTION 4. Payment of Expenses.

(a) Expenses. The Company will pay or cause to be paid all expenses incident to the performance of its obligations under this Agreement, including (i) the preparation, printing and filing of the Registration Statement (including financial statements and exhibits) as originally filed and each amendment thereto, (ii) the preparation, printing and delivery to the Underwriters of copies of each preliminary prospectus, each Issuer Free Writing Prospectus and the Prospectus and any amendments or supplements thereto and any costs associated with electronic delivery of any of the foregoing by the Underwriters to investors, (iii) the preparation, issuance and delivery of the certificates or security entitlements for the Shares to the Underwriters, including any stock or other transfer taxes and any stamp or other duties payable upon the sale, issuance or delivery of the Shares to the Underwriters, (iv) the fees and disbursements of the Company’s counsel, accountants and other advisors, (v) the qualification of the Shares under securities laws in accordance with the provisions of Section 3(e) hereof, including filing fees and the reasonable fees and disbursements of counsel for the Underwriters in connection therewith and in connection with the preparation of a “Blue Sky Survey” and any supplement thereto, (vi) the fees and expenses of any transfer agent or registrar for the Shares, (vii) the costs and expenses of the Company relating to investor presentations on any “road show” undertaken in connection with the marketing of the Shares, including without limitation, expenses associated with the production of road show slides and graphics, fees and expenses of any consultants engaged in connection with the road show presentations, travel and lodging expenses of the representatives and officers of the Company and any such consultants, and 50% of the cost of aircraft and other transportation chartered in connection with the road show, (viii) the filing fees incident to, and the reasonable fees and disbursements of counsel to the Underwriters in connection with, any filing with FINRA and determining the compliance of the terms of the sale of the Shares with FINRA’s rules in an amount not to exceed $15,000, (ix) the fees and expenses incurred in connection with the listing of the Shares on the Nasdaq Global Market, and (x) the costs and expenses (including, without limitation, any damages or other amounts payable in connection with legal or contractual liability) associated with the reforming of any contracts for sale of the Shares made by the Underwriters caused by a breach of the representation contained in the third sentence of Section 1(a)(ii).

(b) Termination of Agreement. If this Agreement is terminated by the Representatives in accordance with the provisions of Section 5, Section 9(a)(i), Section 9(a)(iii) or Section 10 hereof, the Company shall reimburse the Underwriters for all of their reasonably documented out-of-pocket expenses, including the reasonable fees and disbursements of counsel for the Underwriters, incurred in connection with this Agreement or the offering contemplated hereunder; provided, however, that if this Agreement is terminated pursuant to Section 10, the Company shall have no obligation to reimburse any out-of-pocket expenses incurred solely by any defaulting Underwriter.

SECTION 5. Conditions of Underwriters’ Obligations. The obligations of the several Underwriters hereunder are subject to the accuracy of the representations and warranties of the Company contained herein or in certificates of any officer of the Company or the Subsidiary delivered pursuant to the provisions hereof, to the performance by the Company of its covenants and other obligations hereunder, and to the following further conditions:

(a) Effectiveness of Registration Statement. The Registration Statement, including any Rule 462(b) Registration Statement, has become effective and, at the Closing Time, no stop order suspending the effectiveness of the Registration Statement or any post-effective amendment thereto has been issued under the 1933 Act, no order preventing or suspending the use of any preliminary prospectus or the Prospectus has been issued and no proceedings for any of those purposes have been instituted or are pending or, to the Company’s knowledge, contemplated; and the Company has complied with each request (if any) from the Commission for additional information to the reasonable satisfaction of counsel to the Underwriters.

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(b) Opinions of Counsel for Company. At the Closing Time, the Representatives shall have received the opinion and the negative assurance letter, each dated the Closing Time, of Wilmer Cutler Pickering Hale and Dorr LLP, counsel for the Company, together with the opinion of Cooley LLP, special counsel for the Company with respect to intellectual property matters, each in form and substance satisfactory to counsel for the Underwriters, together with signed or reproduced copies of each such opinion and letter for each of the other Underwriters to the effect set forth in Exhibits A-1 and A-2 hereto and to such further effect as counsel to the Underwriters may reasonably request.

(c) Opinion of Counsel for Underwriters. At the Closing Time, the Representatives shall have received the opinion, and negative assurance letter, each dated the Closing Time, of Covington & Burling LLP, counsel for the Underwriters, together with signed or reproduced copies of such opinions and letters for each of the other Underwriters, in form and substance satisfactory to the Representatives. In giving such opinion such counsel may rely, as to all matters governed by the laws of jurisdictions other than the law of the State of New York, the General Corporation Law of the State of Delaware and the federal securities laws of the United States, upon the opinions of counsel satisfactory to the Representatives. Such counsel may also state that, insofar as such opinion involves factual matters, they have relied, to the extent they deem proper, upon certificates of officers and other representatives of the Company and the Subsidiary and certificates of public officials.

(d) Officers’ Certificate. At the Closing Time, there shall not have been, since the date hereof or since the respective dates as of which information is given in the Registration Statement, the General Disclosure Package or the Prospectus, any material adverse change in the condition, financial or otherwise, or in the earnings, business affairs or business prospects of the Company and the Subsidiary considered as one enterprise, whether or not arising in the ordinary course of business, and the Representatives shall have received a certificate of the principal executive officer of the Company and of the principal financial officer of the Company, dated the Closing Time, to the effect that (i) there has been no such material adverse change, (ii) the representations and warranties of the Company in this Agreement are true and correct with the same force and effect as though expressly made at and as of the Closing Time, (iii) the Company has complied with all agreements and satisfied all conditions on its part to be performed or satisfied at or prior to the Closing Time, and (iv) no stop order suspending the effectiveness of the Registration Statement under the 1933 Act has been issued, no order preventing or suspending the use of any preliminary prospectus or the Prospectus has been issued and no proceedings for any of those purposes have been instituted or are pending or, to their knowledge, contemplated.

(e) Accountant’s Comfort Letter. At the time of the execution of this Agreement, the Representatives shall have received from Ernst & Young LLP a letter, dated such date, in form and substance satisfactory to the Representatives, together with signed or reproduced copies of such letter for each of the other Underwriters, containing statements and information of the type ordinarily included in accountants’ “comfort letters” to underwriters with respect to the financial statements and certain financial information contained in the Registration Statement, the General Disclosure Package and the Prospectus.

(f) Bring-down Comfort Letter. At the Closing Time, the Representatives shall have received from Ernst & Young LLP a letter, dated as of the Closing Time, to the effect that they reaffirm the statements made in the letter furnished pursuant to subsection (e) of this Section, except that the specified date referred to shall be a date not more than three business days prior to the Closing Time.

(g) Approval of Listing. At the Closing Time, the Shares shall have been approved for listing on the Nasdaq Global Market, subject only to official notice of issuance.

(h) No Objection. If the offering is subject to review by FINRA, FINRA has confirmed that it has not raised any objection with respect to the fairness and reasonableness of the underwriting terms and arrangements relating to the offering of the Shares.

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(i) Lock-up Agreements. At the Closing Time, the Representatives shall have received an agreement substantially in the form of Exhibit B hereto signed by all of the Company’s directors and officers.

(j) [Reserved].

(k) Additional Documents. At the Closing Time, counsel for the Underwriters shall have been furnished with such other documents and opinions as they may reasonably require for the purpose of enabling them to pass upon the issuance and sale of the Shares as herein contemplated, or in order to evidence the accuracy of any of the representations or warranties, or the fulfillment of any of the conditions, herein contained; and all proceedings taken by the Company in connection with the issuance and sale of the Shares as herein contemplated shall be reasonably satisfactory in form and substance to the Representatives and counsel for the Underwriters.

(l) Termination of Agreement. If any condition specified in this Section shall not have been fulfilled when and as required to be fulfilled, this Agreement may be terminated by the Representatives by notice to the Company at any time at or prior to Closing Time, and such termination shall be without liability of any party to any other party except as provided in Section 4 and except that Sections 1, 4, 6, 7, 8, 14, 15, 16 and 17 shall survive any such termination and remain in full force and effect.

SECTION 6. Indemnification.

(a) Indemnification of Underwriters. The Company agrees to indemnify and hold harmless each Underwriter, its affiliates (as such term is defined in Rule 501(b) under the 1933 Act (each, an “Affiliate”)), its selling agents and each person, if any, who controls any Underwriter within the meaning of Section 15 of the 1933 Act or Section 20 of the 1934 Act as follows:

(i) against any and all loss, liability, claim, damage and expense whatsoever, as incurred, arising out of any untrue statement or alleged untrue statement of a material fact contained in the Registration Statement (or any amendment thereto), including any information deemed to be a part thereof pursuant to Rule 430B, or the omission or alleged omission therefrom of a material fact required to be stated therein or necessary to make the statements therein not misleading or arising out of any untrue statement or alleged untrue statement of a material fact included (A) in any preliminary prospectus, any Issuer Free Writing Prospectus, any Written Testing-the-Waters Communication, the General Disclosure Package or the Prospectus (or any amendment or supplement thereto), or (B) in any materials or information provided to investors by, or with the approval of, the Company in connection with the marketing of the offering of the Shares (“Marketing Materials”), including any roadshow or investor presentations made to investors by the Company (whether in person or electronically), or the omission or alleged omission in any preliminary prospectus, any Issuer Free Writing Prospectus, any Written Testing-the-Waters Communication, the General Disclosure Package, the Prospectus (or any amendment or supplement thereto) or in any Marketing Materials of a material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading;

(ii) against any and all loss, liability, claim, damage and expense whatsoever, as incurred, to the extent of the aggregate amount paid in settlement of any litigation, or any investigation or proceeding by any governmental agency or body, commenced or threatened, or of any claim whatsoever based upon any such untrue statement or omission, or any such alleged untrue statement or omission; provided that (subject to Section 6(d) below) any such settlement is effected with the written consent of the Company;

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(iii) against any and all expense whatsoever, as incurred (including the fees and disbursements of counsel chosen by the Representatives), reasonably incurred in investigating, preparing or defending against any litigation, or any investigation or proceeding by any governmental agency or body, commenced or threatened, or any claim whatsoever based upon any such untrue statement or omission, or any such alleged untrue statement or omission, to the extent that any such expense is not paid under (i) or (ii) above;

provided, however, that this indemnity agreement shall not apply to any loss, liability, claim, damage or expense to the extent arising out of any untrue statement or omission or alleged untrue statement or omission made in the Registration Statement (or any amendment thereto), including any information deemed to be a part thereof pursuant to Rule 430B, the General Disclosure Package or the Prospectus (or any amendment or supplement thereto) in reliance upon and in conformity with the Underwriter Information.

(b) Indemnification of Company, Directors and Officers. Each Underwriter severally agrees to indemnify and hold harmless the Company, its directors, each of its officers who signed the Registration Statement, and each person, if any, who controls the Company within the meaning of Section 15 of the 1933 Act or Section 20 of the 1934 Act, against any and all loss, liability, claim, damage and expense described in the indemnity contained in subsection (a) of this Section, as incurred, but only with respect to untrue statements or omissions, or alleged untrue statements or omissions, made in the Registration Statement (or any amendment thereto), including any information deemed to be a part thereof pursuant to Rule 430B, the General Disclosure Package or the Prospectus (or any amendment or supplement thereto) in reliance upon and in conformity with the Underwriter Information.

(c) Actions against Parties; Notification. Each indemnified party shall give notice as promptly as reasonably practicable to each indemnifying party of any action commenced against it in respect of which indemnity may be sought hereunder, but failure to so notify an indemnifying party shall not relieve such indemnifying party from any liability hereunder to the extent it is not materially prejudiced as a result thereof and in any event shall not relieve it from any liability which it may have otherwise than on account of this indemnity agreement. In the case of parties indemnified pursuant to Section 6(a) above, counsel to the indemnified parties shall be selected by the Representatives, and, in the case of parties indemnified pursuant to Section 6(b) above, counsel to the indemnified parties shall be selected by the Company. An indemnifying party may participate at its own expense in the defense of any such action; provided, however, that counsel to the indemnifying party shall not (except with the consent of the indemnified party) also be counsel to the indemnified party. In no event shall the indemnifying parties be liable for the reasonable fees and expenses of more than one counsel (in addition to any local counsel) separate from their own counsel for all indemnified parties in connection with any one action or separate but similar or related actions in the same jurisdiction arising out of the same general allegations or circumstances. No indemnifying party shall, without the prior written consent of the indemnified parties, settle or compromise or consent to the entry of any judgment with respect to any litigation, or any investigation or proceeding by any governmental agency or body, commenced or threatened, or any claim whatsoever in respect of which indemnification or contribution could be sought under this Section 6 or Section 7 hereof (whether or not the indemnified parties are actual or potential parties thereto), unless such settlement, compromise or consent (i) includes an unconditional release of each indemnified party from all liability arising out of such litigation, investigation, proceeding or claim and (ii) does not include a statement as to or an admission of fault, culpability or a failure to act by or on behalf of any indemnified party.

(d) Settlement without Consent if Failure to Reimburse. If at any time an indemnified party shall have requested an indemnifying party to reimburse the indemnified party for fees and expenses of counsel, such indemnifying party agrees that it shall be liable for any settlement of the nature contemplated by Section 6(a)(ii) effected without its written consent if (i) such settlement is entered into more than 45 days after receipt by such indemnifying party of the aforesaid request, (ii) such indemnifying party shall have received notice of the terms of such settlement at least 30 days prior to such settlement being entered into and (iii) such indemnifying party shall not have reimbursed such indemnified party in accordance with such request prior to the date of such settlement.

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SECTION 7. Contribution. If the indemnification provided for in Section 6 hereof is for any reason unavailable to or insufficient to hold harmless an indemnified party in respect of any losses, liabilities, claims, damages or expenses referred to therein, then each indemnifying party shall contribute to the aggregate amount of such losses, liabilities, claims, damages and expenses incurred by such indemnified party, as incurred, (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 hand, from the offering of the Shares pursuant to this Agreement 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) above but also the relative fault of the Company, on the one hand, and of the Underwriters, on the other hand, in connection with the statements or omissions which resulted in such losses, liabilities, claims, damages or expenses, 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 hand, in connection with the offering of the Shares pursuant to this Agreement shall be deemed to be in the same respective proportions as the total net proceeds from the offering of the Shares pursuant to this Agreement (before deducting expenses) received by the Company, on the one hand, and the total underwriting discount received by the Underwriters, on the other hand, in each case as set forth on the cover of the Prospectus, bear to the aggregate initial public offering price of the Shares as set forth on the cover of the Prospectus.

The relative fault of the Company, on the one hand, and the Underwriters, on the other hand, shall be determined by reference to, among other things, whether any such untrue or alleged untrue statement of a material fact or 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.

The Company and the Underwriters agree that it would not be just and equitable if contribution pursuant to this Section 7 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 which does not take account of the equitable considerations referred to above in this Section 7. The aggregate amount of losses, liabilities, claims, damages and expenses incurred by an indemnified party and referred to above in this Section 7 shall be deemed to include any legal or other expenses reasonably incurred by such indemnified party in investigating, preparing or defending against any litigation, or any investigation or proceeding by any governmental agency or body, commenced or threatened, or any claim whatsoever based upon any such untrue or alleged untrue statement or omission or alleged omission.

Notwithstanding the provisions of this Section 7, no Underwriter shall be required to contribute any amount in excess of the underwriting discounts and commissions received by such Underwriter in connection with the Shares underwritten by it and distributed to the public.

No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the 1933 Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation.

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For purposes of this Section 7, each person, if any, who controls an Underwriter within the meaning of Section 15 of the 1933 Act or Section 20 of the 1934 Act and each Underwriter’s Affiliates and selling agents shall have the same rights to contribution as such Underwriter, and each director of the Company, each officer of the Company who signed the Registration Statement, and each person, if any, who controls the Company within the meaning of Section 15 of the 1933 Act or Section 20 of the 1934 Act shall have the same rights to contribution as the Company. The Underwriters’ respective obligations to contribute pursuant to this Section 7 are several in proportion to the number of Shares set forth opposite their respective names in Schedule A hereto and not joint.

SECTION 8. Representations, Warranties and Agreements to Survive. All representations, warranties and agreements contained in this Agreement or in certificates of officers of the Company or the Subsidiary submitted pursuant hereto, shall remain operative and in full force and effect regardless of (i) any investigation made by or on behalf of any Underwriter or its Affiliates or selling agents, any person controlling any Underwriter, its officers or directors or any person controlling the Company and (ii) delivery of and payment for the Shares.

SECTION 9. Termination of Agreement.

(a) Termination. The Representatives may terminate this Agreement, by notice to the Company, at any time at or prior to the Closing Time (i) if there has been, in the judgment of the Representatives, since the time of execution of this Agreement or since the respective dates as of which information is given in the Registration Statement, the General Disclosure Package or the Prospectus, any material adverse change in the condition, financial or otherwise, or in the earnings, business affairs or business prospects of the Company and the Subsidiary considered as one enterprise, whether or not arising in the ordinary course of business, or (ii) if there has occurred any material adverse change in the financial markets in the United States or the international financial markets, any outbreak of hostilities or escalation thereof or other calamity or crisis or any change or development involving a prospective change in U.S. or international political, financial or economic conditions, in each case the effect of which is such as to make it, in the judgment of the Representatives, impracticable or inadvisable to proceed with the completion of the offering or to enforce contracts for the sale of the Shares, or (iii) if trading in any securities of the Company has been suspended or materially limited by the Commission or the Nasdaq Global Market, or (iv) if trading generally on the NYSE MKT or the New York Stock Exchange or in the Nasdaq Global Market has been suspended or materially limited, or minimum or maximum prices for trading have been fixed, or maximum ranges for prices have been required, by any of said exchanges or by order of the Commission, FINRA or any other governmental authority, or (v) a material disruption has occurred in commercial banking or securities settlement or clearance services in the United States or with respect to Clearstream or Euroclear systems in Europe, or (vi) if a banking moratorium has been declared by either Federal or New York authorities.

(b) Liabilities. If this Agreement is terminated pursuant to this Section, such termination shall be without liability of any party to any other party except as provided in Section 4 hereof, and provided further that Sections 1, 4, 6, 7, 8, 15, 16 and 17 shall survive such termination and remain in full force and effect.

SECTION 10. Default by One or More of the Underwriters. If one or more of the Underwriters shall fail at the Closing Time to purchase the Shares which it or they are obligated to purchase under this Agreement (the “Defaulted Securities”), the Representatives shall have the right, within 24 hours thereafter, to make arrangements for one or more of the non-defaulting Underwriters, or any other underwriters, to purchase all, but not less than all, of the Defaulted Securities in such amounts as may be agreed upon and upon the terms herein set forth; if, however, the Representatives shall not have completed such arrangements within such 24-hour period, then:

(i) if the number of Defaulted Securities does not exceed 10% of the number of Shares to be purchased, each of the non-defaulting Underwriters shall be obligated, severally and not jointly, to purchase the full amount thereof in the proportions that their respective underwriting obligations hereunder bear to the underwriting obligations of all non-defaulting Underwriters, or

(ii) if the number of Defaulted Securities exceeds 10% of the number of Shares to be purchased, this Agreement shall terminate without liability on the part of any non-defaulting Underwriter.

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No action taken pursuant to this Section shall relieve any defaulting Underwriter from liability in respect of its default.

In the event of any such default which does not result in a termination of this Agreement, either (i) the Representatives or (ii) the Company shall have the right to postpone Closing Time, as the case may be, for a period not exceeding seven days in order to effect any required changes in the Registration Statement, the General Disclosure Package or the Prospectus or in any other documents or arrangements. As used herein, the term “Underwriter” includes any person substituted for an Underwriter under this Section 10.

SECTION 11. Notices. All notices and other communications hereunder shall be in writing and shall be deemed to have been duly given if mailed or transmitted by any standard form of telecommunication. Notices to the Underwriters shall be directed to Leerink Partners LLC at 1301 Avenue of the Americas, 5^th Floor, New York, New York 10019, attention of Stuart R. Nayman; Stifel, Nicolaus & Company, Incorporated, 787 7th Avenue, 11th Floor, New York, NY 10019, attention of Michael Gilbert; and Oppenheimer & Co. Inc., 85 Broad Street, New York, New York 10004, attention of General Counsel; with a copy, which shall not constitute notice, to Covington & Burling LLP at 620 Eighth Avenue, New York, New York 10018, attention of Brian K. Rosenzweig. Notices to the Company shall be directed to 195 Church Street, 14^th Floor, New Haven, Connecticut 06510, attention of Lisa Delfini; with a copy, which shall not constitute notice, to Wilmer Cutler Pickering Hale and Dorr LLP, 60 State Street, Boston, Massachusetts 02109, attention of Stuart M. Falber.

SECTION 12. No Advisory or Fiduciary Relationship. The Company acknowledges and agrees that (a) the purchase and sale of the Shares pursuant to this Agreement, including the determination of the initial public offering price of the Shares and any related discounts and commissions, is an arm’s-length commercial transaction between the Company, on the one hand, and the several Underwriters, on the other hand, (b) in connection with the offering of the Shares and the process leading thereto, each Underwriter is and has been acting solely as a principal and is not the agent or fiduciary of the Company, the Subsidiary or their respective stockholders, creditors, employees or any other party, (c) no Underwriter has assumed or will assume an advisory or fiduciary responsibility in favor of the Company with respect to the offering of the Shares or the process leading thereto (irrespective of whether such Underwriter has advised or is currently advising the Company or the Subsidiary on other matters) and no Underwriter has any obligation to the Company with respect to the offering of the Shares except the obligations expressly set forth in this Agreement, (d) the Underwriters and their respective affiliates may be engaged in a broad range of transactions that involve interests that differ from those of the Company and (e) the Underwriters have not provided any legal, accounting, regulatory or tax advice with respect to the offering of the Shares and the Company has consulted its own respective legal, accounting, regulatory and tax advisors to the extent it deemed appropriate.

SECTION 13. Recognition of the U.S. Special Resolution Regimes. 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.

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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.

For purposes of this Agreement, (A) “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); (B) “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 (iii) a “covered FSI” as that term is defined in, and interpreted in accordance with, 12 C.F.R. § 382.2(b); (C) “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; and (D) “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.

SECTION 14. Parties. This Agreement shall inure to the benefit of and be binding upon the Underwriters and the Company and their respective successors. Nothing expressed or mentioned in this Agreement is intended or shall be construed to give any person, firm or corporation, other than the Underwriters and the Company and their respective successors and the controlling persons and officers and directors referred to in Sections 6 and 7 and their heirs and legal representatives, any legal or equitable right, remedy or claim under or in respect of this Agreement or any provision herein contained. This Agreement and all conditions and provisions hereof are intended to be for the sole and exclusive benefit of the Underwriters and the Company and their respective successors, and said controlling persons and officers and directors and their heirs and legal representatives, and for the benefit of no other person, firm or corporation. No purchaser of Shares from any Underwriter shall be deemed to be a successor by reason merely of such purchase.

SECTION 15. Waiver of Trial by Jury. The Company (on its behalf and, to the extent permitted by applicable law, on behalf of its stockholders and affiliates) and each of the Underwriters hereby irrevocably waives, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding arising out of or relating to this Agreement or the transactions contemplated hereby.

SECTION 16. 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 WITHOUT REGARD TO ITS CHOICE OF LAW PROVISIONS.

SECTION 17. Consent to Jurisdiction; Waiver of Immunity. Any legal suit, action or proceeding arising out of or based upon this Agreement or the transactions contemplated hereby shall be instituted in (i) the federal courts of the United States of America located in the City and County of New York, Borough of Manhattan or (ii) the courts of the State of New York located in the City and County of New York, Borough of Manhattan (collectively, the “Specified Courts”), and each party irrevocably submits to the exclusive jurisdiction (except for proceedings instituted in regard to the enforcement of a judgment of any such court, as to which such jurisdiction is non-exclusive) of such courts in any such suit, action or proceeding. Service of any process, summons, notice or document by mail to such party’s address set forth above shall be effective service of process for any suit, action or other proceeding brought in any such court. The parties irrevocably and unconditionally waive any objection to the laying of venue of any suit, action or other proceeding in the Specified Courts and irrevocably and unconditionally waive and agree not to plead or claim in any such court that any such suit, action or other proceeding brought in any such court has been brought in an inconvenient forum.

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SECTION 18. TIME. TIME SHALL BE OF THE ESSENCE OF THIS AGREEMENT. EXCEPT AS OTHERWISE SET FORTH HEREIN, SPECIFIED TIMES OF DAY REFER TO NEW YORK CITY TIME.

SECTION 19. Partial Unenforceability. The invalidity or unenforceability of any Section, paragraph or provision of this Agreement shall not affect the validity or enforceability of any other Section, paragraph or provision hereof. If any Section, paragraph or provision of this Agreement is for any reason determined to be invalid or unenforceable, there shall be deemed to be made such minor changes (and only such minor changes) as are necessary to make it valid and enforceable.

SECTION 20. Counterparts. This Agreement may be executed in any number of counterparts (which may include counterparts delivered by any standard form of telecommunication), each of which shall be deemed to be an original, but all such counterparts shall together constitute one and the same agreement. Counterparts may be delivered via facsimile, electronic mail (including any electronic signature covered by the U.S. federal ESIGN Act of 2000, Uniform Electronic Transactions Act, the Electronic Signatures and Records Act or other applicable law, e.g., www.docusign.com) or other transmission method and any counterpart so delivered shall be deemed to have been duly and validly delivered and be valid and effective for all purposes.

SECTION 21. Effect of Headings. The Section headings herein are for convenience only and shall not affect the construction hereof.

SECTION 22. Entire Agreement. This Agreement supersedes all prior agreements and understandings (whether written or oral) between the Company and the Underwriters, or any of them, with respect to the subject matter hereof.

[SIGNATURE PAGES FOLLOW]

29

If the foregoing is in accordance with your understanding of our agreement, please sign and return to the Company a counterpart hereof, whereupon this instrument, along with all counterparts, will become a binding agreement among the Underwriters and the Company in accordance with its terms.

For themselves and as Representatives of the other Underwriters named in Schedule A hereto.

[SIGNATURE PAGE TO UNDERWRITING AGREEMENT]

SCHEDULE A

The offering price to investors per Share shall be $4.00.

The purchase price per Share to be paid by the several Underwriters shall be $3.76, being the amount equal to the offering price to investors set forth above less $0.24 per Share.

SCHEDULE B-1

Pricing Terms

SCHEDULE B-2

Free Writing Prospectuses

None.

SCHEDULE B-3

List of Written Testing-the-Waters Communications

None.

Exhibit A-1

Form of Opinion of Wilmer Cutler Pickering Hale and Dorr LLP

Exhibit A-2

Form of Opinion of Cooley LLP

Exhibit B

FORM OF LOCK-UP AGREEMENT

Lock-Up Agreement

December __, 2024

Leerink Partners LLC

Stifel, Nicolaus & Company, Incorporated

Oppenheimer & Co. Inc.

c/o Leerink Partners LLC

1301 Avenue of the Americas, 5^th Floor

New York, NY 10019

c/o Stifel, Nicolaus & Company, Incorporated

787 7^th Avenue, 11^th Floor

New York, NY 10019

c/o Oppenheimer & Co. Inc.

85 Broad Street

New York, NY 10004

Ladies and Gentlemen:

The undersigned, an officer and/or director of Trevi Therapeutics, Inc., a Delaware corporation (the “Company”), understands that Leerink Partners LLC (“Leerink Partners”), Stifel, Nicolaus & Company, Incorporated and Oppenheimer & Co. Inc. (together, the “Representatives”) propose to enter into an Underwriting Agreement (the “Underwriting Agreement”) with the Company providing for the public offering (the “Public Offering”) of shares of the Company’s common stock, par value $0.001 per share (the “Common Stock”) and any other securities as may be determined to be issued by the Company pursuant to the Underwriting Agreement (the “Securities”). In recognition of the benefit that such an offering will confer upon the undersigned as an officer and/or a director of the Company, and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the undersigned agrees with each underwriter to be named in the Underwriting Agreement (collectively, the “Underwriters”) that, during the period beginning on the date hereof and ending on the date that is 45 days from the date of the Underwriting Agreement (the “Lock-Up Period”), the undersigned will not, without the prior written consent of Leerink Partners, on behalf of the Underwriters, directly or indirectly, (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 for the sale of, or otherwise dispose of or transfer any shares of Common Stock or any securities convertible into or exchangeable or exercisable for Common Stock, whether now owned or hereafter acquired by the undersigned or with respect to which the undersigned has or hereafter acquires the power of disposition (collectively, the “Lock-Up Securities”), or exercise any right with respect to the registration of any of the Lock-Up Securities, or file or cause to be filed any registration statement in connection therewith, under the Securities Act of 1933, as amended, or (ii) enter into any swap or any other agreement or any transaction that transfers, in whole or in part, directly or indirectly, the economic consequence of ownership of the Lock-Up Securities, whether any such swap or transaction is to be settled by delivery of Common Stock or other securities, in cash or otherwise.

2

Notwithstanding the foregoing, and subject to the conditions below, the undersigned may transfer Lock-Up Securities without the prior written consent of Leerink Partners, provided, in each case, that (1) the Representatives receive a signed lock-up agreement for the balance of the Lock-Up Period from each donee, trustee, distributee or transferee, as the case may be, (2) any such transfer shall not involve a disposition for value, (3) in the case of clauses (ii) through (iv) and (vii) below, such transfers are not required to be reported with the Securities and Exchange Commission on Form 4 in accordance with Section 16 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and in the case of clauses (i), (v) and (vi) below, to the extent any Form 4 or Form 5 is required to be or is voluntarily filed in accordance with Section 16 of the Exchange Act, such Form 4 or Form 5 clearly indicates in the footnotes thereto an explanation of the type of transaction giving rise to the change in ownership and (4) the undersigned does not otherwise voluntarily effect any public filing or report regarding such transfers (other than a filing on a Form 5 made after the expiration of the Lock-Up Period):

Furthermore, no provision in this lock-up agreement shall be deemed to restrict or prohibit (1) the transfer of the undersigned’s Lock-Up Securities to the Company in connection with the termination of the undersigned’s services to the Company, provided that any filing under Section 16 of the Exchange Act made in connection with such transfer shall clearly indicate in the footnotes thereto that the filing relates to the circumstances described in this clause (1); (2) the exercise or exchange by the undersigned of any option or warrant to acquire any shares of Common Stock or options to purchase shares of Common Stock, in each case for cash or on a “cashless” or “net exercise” basis, pursuant to any stock option, stock bonus or other stock plan or arrangement in existence as of the date of the Underwriting Agreement; provided, however, that the underlying shares of Common Stock shall continue to be subject to the restrictions on transfer set forth in this lock-up agreement and that any filing under Section 16 of the Exchange Act made in connection with such exercise or exchange shall clearly indicate in the footnotes thereto that (a) the filing relates to the circumstances described in this clause (2) and (b) no shares of Common Stock were sold by the reporting person; (3) the transfer of Lock-Up Securities upon the completion of a bona fide third-party tender offer,

3

merger, consolidation or other similar transaction made to all holders of the Company’s securities involving a change of control of the Company; provided, however, that in the event that such tender offer, merger, consolidation or other such transaction is not completed, the Lock-Up Securities held by the undersigned shall remain subject to the restrictions on transfer set forth in this lock-up agreement; and (4) the sale or disposal of or transfer of shares of Common Stock purchased by the undersigned in the Public Offering or on the open market following the Public Offering, provided that no filing by any party under the Exchange Act or other public announcement shall be required or shall be made voluntarily in connection with such sale, disposal or transfer (other than a filing on a Form 5 made after the expiration of the Lock-Up Period).

Notwithstanding anything herein to the contrary, nothing herein shall prevent the undersigned from transferring or disposing of Lock-Up Securities pursuant to a 10b5-1 trading plan that complies with Rule 10b5-1 under the Exchange Act (a “10b5-1 Trading Plan”), provided that such 10b5-1 Trading Plan was established prior to the execution of this lock-up agreement by the undersigned, and nothing herein shall prevent the undersigned from establishing a new 10b5-1 Trading Plan or from amending an existing 10b5-1 Trading Plan so long as there are no sales of Lock-Up Securities under any such new or amended 10b5-1 Trading Plan during the Lock-Up Period; and provided that the establishment of a 10b5-1 Trading Plan or the amendment of a 10b5-1 Trading Plan shall only be permitted if the undersigned does not effect any public filing or report regarding the establishment or amendment of such 10b5-1 Trading Plan during the Lock-Up Period, except as required under the Exchange Act.

The undersigned also agrees and consents to the entry of stop transfer instructions with the Company’s transfer agent and registrar preventing the transfer of the Lock-Up Securities except in compliance with the foregoing restrictions. This lock-up agreement shall automatically terminate, and the undersigned shall be released from the undersigned’s obligations hereunder, upon the earliest to occur, if any, of (i) prior to the execution of the Underwriting Agreement, the Representatives, on behalf of the Underwriters, advise the Company in writing or the Company advises the Representatives in writing that it has determined not to proceed with the Public Offering; (ii) the Underwriting Agreement is executed but is terminated prior to the closing of the Public Offering (other than the provisions thereof which survive termination), or (iii) December 27, 2024, in the event that the Underwriting Agreement has not been executed by such date.

This agreement shall be governed by, and construed in accordance with, the laws of the State of New York.

[SIGNATURE PAGE FOLLOWS]

4

(indicate capacity of person signing if signing as custodian, trustee, or on behalf of an entity)

5

Exhibit 5.1

December 16, 2024

+1 617 526 6000 (t)

+1 617 526 5000 (f)

wilmerhale.com

Trevi Therapeutics, Inc.

195 Church Street, 16th Floor

New Haven, Connecticut 06510

Ladies and Gentlemen:

This opinion is furnished to you in connection with (i) the Registration Statement on Form S-3 (File No. 333-273030) (the “Registration Statement”) filed by Trevi Therapeutics, Inc., a Delaware corporation (the “Company”), with the Securities and Exchange Commission (the “Commission”) under the Securities Act of 1933, as amended (the “Securities Act”), for the registration of, among other things, an indeterminate number of shares of the Company’s common stock, $0.001 par value per share (the “Common Stock”), which may be issued from time to time on a delayed or continuous basis pursuant to Rule 415 under the Securities Act at an initial aggregate offering price not to exceed $200,000,000, as set forth in the Registration Statement and the base prospectus contained therein (the “Base Prospectus”), and (ii) the prospectus supplement, dated December 15, 2024 (the “Prospectus Supplement” and, together with the Base Prospectus, the “Prospectus”), relating to the issuance and sale pursuant to the Registration Statement of 12,500,000 shares of Common Stock (the “Shares”).

The Shares are to be issued and sold by the Company pursuant to an underwriting agreement, dated as of December 15, 2024 (the “Underwriting Agreement”), by and among the Company and Leerink Partners LLC, Stifel, Nicolaus & Company, Incorporated and Oppenheimer & Co. Inc., as representatives of the several underwriters named in the Underwriting Agreement, which is filed as Exhibit 1.1 to the Company’s Current Report on Form 8-K, filed on the date hereof.

We have acted as counsel for the Company in connection with the issue and sale by the Company of the Shares. We have examined and relied upon copies of the Registration Statement and the Prospectus, each as filed with the Commission. We have also examined and relied upon the Underwriting Agreement, minutes of meetings and actions of the stockholders and the Board of Directors of the Company, including the committees thereof, as provided to us by the Company, the Certificate of Incorporation and Bylaws of the Company, each as restated and/or amended to date, and such other documents as we have deemed necessary for purposes of rendering the opinions hereinafter set forth.

In our examination of the foregoing documents, we have assumed the genuineness of all signatures, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted to us as copies, the authenticity of the originals of such latter documents and the legal competence of all signatories to such documents.

We express no opinion herein as to the laws of any state or jurisdiction other than the General Corporation Law of the State of Delaware and the state laws of New York.

Wilmer Cutler Pickering Hale and Dorr LLP, 60 State Street, Boston, Massachusetts 02109

Beijing  Berlin  Boston  Brussels  Denver  Frankfurt  London  Los Angeles  New York  Palo Alto  San Francisco  Washington

Based upon and subject to the foregoing, we are of the opinion that the Shares have been duly authorized for issuance and, when the Shares are issued and paid for in accordance with the terms and conditions of the Underwriting Agreement, the Shares will be validly issued, fully paid and nonassessable.

Please note that we are opining only as to the matters expressly set forth herein, and no opinion should be inferred as to any other matters. This opinion is based upon currently existing statutes, rules, regulations and judicial decisions, and we disclaim any obligation to advise you of any change in any of these sources of law or subsequent legal or factual developments which might affect any matters or opinions set forth herein.

We hereby consent to the filing of this opinion with the Commission in accordance with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act as an exhibit to the Current Report on Form 8-K to be filed by the Company on the date hereof in connection with the issuance and sale of the Shares and to the use of our name therein and in the Prospectus under the caption “Legal Matters.” In giving such consent, we do not hereby admit that we are in the category of persons whose consent is required under Section 7 of the Securities Act or the rules and regulations of the Commission.

Exhibit 99.1

Trevi Therapeutics Announces Pricing of $50 Million Underwritten Offering

New Haven, Conn., December 16, 2024 – Trevi Therapeutics, Inc. (Nasdaq: TRVI), a clinical-stage biopharmaceutical company developing the investigational therapy, Haduvio^™ (oral nalbuphine ER) for the treatment of chronic cough in idiopathic pulmonary fibrosis (IPF) and refractory chronic cough (RCC), today announced the pricing of an underwritten offering of 12,500,000 shares of its common stock at a price to investors of $4.00 per share, for total proceeds of $50 million, before deducting underwriting discounts and commissions and expenses payable by Trevi. All of the shares in the offering are being sold by Trevi. The offering is expected to close on December 17, 2024, subject to satisfaction of customary closing conditions.

The financing includes participation from new and existing investors, including Adage Capital Partners LP, Frazier Life Sciences, Logos Capital, MPM BioImpact, Rubric Capital Management LP and Vivo Capital.

Leerink Partners, Stifel and Oppenheimer & Co. are acting as joint book-running managers for the offering. Needham & Company is acting as lead manager for the offering. Jones and B. Riley Securities are acting as co-managers for the offering.

The shares are being offered by Trevi pursuant to a shelf registration statement on Form S-3 (File No. 333-273030), which was filed with the Securities and Exchange Commission (SEC) on June 29, 2023 and declared effective by the SEC on August 15, 2023. This offering is being made only by means of a prospectus supplement and the accompanying prospectus that form a part of the registration statement. The final terms of the offering will be disclosed in a prospectus supplement to be filed with the SEC. When available, copies of the prospectus supplement and the accompanying prospectus may also be obtained from Leerink Partners LLC, Attention: Syndicate Department, 53 State Street, 40th Floor, Boston, MA 02109, or by telephone at (800) 808-7525, ext. 6105, or by email at syndicate@leerink.com; from Stifel, Nicolaus & Company, Incorporated, Attention: Syndicate, One Montgomery Street, Suite 3700, San Francisco, CA 94104, by telephone at (415) 364-2720 or by email at syndprospectus@stifel.com; or from Oppenheimer & Co. Inc., Attention: Syndicate Prospectus Department, 85 Broad Street, 26th Floor, New York, NY 10004, by telephone at (212) 667-8055, or by email at EquityProspectus@opco.com.

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

About Trevi Therapeutics, Inc.

Trevi Therapeutics, Inc. is a clinical-stage biopharmaceutical company developing the investigational therapy Haduvio^™ (oral nalbuphine extended-release) for the treatment of chronic cough in patients with idiopathic pulmonary fibrosis (IPF) and refractory chronic cough (RCC). Haduvio acts on the cough reflex arc both centrally and peripherally as a kappa agonist and a mu antagonist (KAMA), which are opioid receptors that play a key role in controlling cough hypersensitivity. Nalbuphine is not currently scheduled by the U.S. Drug Enforcement Agency.

Forward-Looking Statements

Statements contained in this press release regarding matters that are not historical facts are “forward-looking statements” within the meaning of the Private Securities Litigation Reform Act of 1995. Such statements are subject to risks and uncertainties and actual results may differ materially from those expressed or implied by such forward-looking statements. Such statements include, but are not limited to, statements about the anticipated closing of the underwritten offering and the expected gross proceeds of the offering, among other things, and other statements containing the words “believes,” “anticipates,” “plans,” “expects,” “may,” and similar expressions. Risks that contribute to the uncertain nature of the forward-looking statements include: uncertainties related to market conditions and whether the conditions for the closing of the offering will be satisfied, as well as other risks and uncertainties, as well as other risks and uncertainties set forth in the “Risk Factors” section of Trevi’s Quarterly Report on Form 10-Q for the quarter ended September 30, 2024 filed with the SEC, and in any subsequent filings with the SEC. All forward-looking statements contained in this press release speak only as of the date on which they were made. Trevi undertakes no obligation to update such statements to reflect events that occur or circumstances that exist after the date on which they were made except as required by law.

Investor Contact

Katie Barrett

Trevi Therapeutics, Inc.

203-304-2499

k.barrett@trevitherapeutics.com

Media Contact

Rosalia Scampoli

914-815-1465

rscampoli@marketcompr.com