Contract analysis

1. Purpose and Engagement Confirmation Calderwood & Harkness LLP (the "Firm" or "Calderwood & Harkness") is pleased to confirm its engagement by Penterra Pharmaceuticals Corp. ("Penterra" or the "Client"), a Delaware corporation publicly traded on the Nasdaq Global Select Market (ticker: PNTR), to serve as outside counsel in connection with the proposed out-licensing of Penterra's proprietary small-molecule compound

2. Scope of Representation Calderwood & Harkness will represent Penterra in its capacity as licensor in connection with the following matters related to the out-licensing of PPC-4187: 2.1 Transaction Structuring and Negotiation. The Firm will advise Penterra on the overall deal structure of the proposed out-license, including the allocation of rights and obligations between licensor and licensee, the delineation of e

3. Engagement Team The following attorneys will comprise the core engagement team for this matter: 3.1 Responsible Partner. Marcus Delgado — Partner, intellectual Property Group. Mr. Delgado will serve as the responsible partner overseeing all aspects of the engagement. He will be the primary point of contact for the Client on all substantive and strategic matters and will have overall responsibility for the quality

4. Fee Arrangement 4.1 Hourly Rates Fees for legal services rendered in connection with this engagement will be charged on an hourly basis. The current standard hourly rates for the attorneys assigned to this engagement are as follows: Paralegal time will be billed at rates ranging from $350 to $450 per hour, depending on seniority and the nature of the tasks performed. If additional attorneys or specialists are assi

5. Client Responsibilities The Client agrees to cooperate fully with the Firm in connection with this engagement and to provide the Firm with timely access to all documents, data, personnel, technical information, and other resources reasonably necessary for the Firm to perform its obligations hereunder. The Client acknowledges that the Firm's ability to provide effective and efficient legal services is dependent upo

6. Confidentiality Calderwood & Harkness will maintain the confidentiality of all information provided by or on behalf of the Client in connection with this engagement, in accordance with the New York Rules of Professional Conduct, applicable rules of professional responsibility, and the protections afforded by the attorney-client privilege and the work product doctrine. The Firm will implement appropriate informatio

7. Conflicts of Interest The Firm has conducted a comprehensive conflict of interest check in accordance with its standard procedures and the applicable provisions of the New York Rules of Professional Conduct. Based on the information currently available to the Firm, the conflict check has not identified any conflicts of interest that would preclude the Firm from undertaking this engagement. The Firm's conflict chec

8. Termination Either party may terminate this engagement at any time upon written notice to the other party, subject to the Firm's professional obligations under applicable rules of professional conduct and any requirements imposed by a court, tribunal, or regulatory body having jurisdiction over any aspect of the matter. Upon termination of the engagement by either party, the Client will remain responsible for the

9. Document Retention Upon conclusion of the engagement, whether by completion of the Transaction, termination of the engagement, or otherwise, the Firm will retain engagement files — including attorney work product, correspondence, memoranda, drafts, and internal notes — in accordance with the Firm's standard document retention policies, as may be amended from time to time. Under the Firm's current policy, engagemen

10. Limitation of Liability / Disclaimer The Firm's legal advice in connection with this engagement is limited to matters of the laws of the State of New York and the federal laws of the United States, including applicable provisions of the Internal Revenue Code, the HSR Act, CFIUS regulations, and the U.S. Patent Act and Lanham Act. The Firm does not hold itself out as qualified to advise on the laws of any foreign

11. Governing Law This engagement letter and the relationship between the Firm and the Client arising hereunder shall be governed by and construed in accordance with the laws of the State of New York, without regard to its conflicts of law principles. Any dispute arising out of or relating to this Letter or the engagement shall be subject to the exclusive jurisdiction of the courts of the State of New York located in

12. Acceptance and Counterparts If the foregoing terms are acceptable to Penterra, we respectfully request that Ms. Fremont, in her capacity as General Counsel and authorized representative of Penterra Pharmaceuticals Corp., sign and return a copy of this Letter to Calderwood & Harkness at the address set forth above, or by email to Marcus Delgado at mdelgado@calderwoodharkness.com, to confirm Penterra's acceptance o