Exhibit 10.1

TRANSITION AGREEMENT AND RELEASE

This Transition Agreement and Release (“Agreement”) is made by and between Mark Kowalski (“Employee”) and Sierra Oncology, Inc. (the “Company”) (collectively referred to as the “Parties” or individually referred to as a “Party”).

RECITALS

WHEREAS, Employee is employed by the Company;

WHEREAS, Employee signed an Employment Agreement with the Company dated December 7, 2016 (the “Original Employment Agreement”);

WHEREAS, Employee subsequently signed Amendments to Employment Agreement with the Company entered into as of April 20, 2017 and June 2, 2021 respectively (together with the Original Employment Agreement, the “Employment Agreement”);

WHEREAS, Employee signed an Employee Proprietary Information, Inventions Assignment and Non-Competition Agreement with the Company (the “Confidentiality Agreement”);

WHEREAS, Employee was granted the stock options (including performance-based stock options) to purchase shares of the Company’s common stock indicated in Schedule 1 hereto (each such grant, an “Option” and together, the “Options”) as of the dates indicated in Schedule 1 hereto, each subject to the terms and conditions of the Company’s 2015 Equity Incentive Plan (the “2015 Plan”) and the terms and conditions of a stock option agreement related to the award (collectively the Plans and the stock option agreements, the “Stock Agreements”);

WHEREAS, Employee and the Company mutually agree that Employee terminated employment with the Company effective March 10, 2022 (the “Termination Date”), at which point Employee became a consultant, which consulting period is expected to last until the Service Separation Date, as defined below, (the “Consulting Period”) pursuant to Employee’s Consulting Agreement with the Company, and will separate from the Company at the end of the Consulting Period, effective at the end of the business day on June 30, 2023 (the date Employee ceases to be in service at the end of the Consulting Period or before, the “Service Separation Date”); and

WHEREAS, the Parties wish to resolve any and all disputes, claims, complaints, grievances, charges, actions, petitions, and demands that the Employee may have against the Company and any of the Releasees as defined below, including, but not limited to, any and all claims arising out of or in any way related to Employee’s employment with or separation from the Company unless excluded below.

NOW, THEREFORE, in consideration of the mutual promises made herein, the Company and Employee hereby agree as follows:

COVENANTS

1.Consideration.  In consideration of Employee’s execution of this Transition Agreement and Employee’s fulfillment of all terms and conditions, the Parties agree as follows:

a.Severance. The Company agrees to pay Employee a total of Four Hundred Seventy-Four Thousand Nine Hundred and Eighty-Six Dollars ($474,986), representing twelve (12) months of Employee’s base salary, at a rate of Thirty-Nine Thousand Five Hundred Eighty-Two Dollars ($39,582) per month, less applicable withholdings, for twelve (12) months from the Termination Date.  The payments to be made pursuant to the prior sentence will commence no later than on the first business day following the sixtieth (60^th) day following the Termination Date, with the first payment to include the payments due and owing prior to such first payment date but for the application of this sentence. For the avoidance of doubt, and not in consideration of Employee’s execution of this Transition Agreement, the Company shall issue Employee’s final paycheck, representing all outstanding wages earned prior to the Termination Date, in addition to eighty and one half (80.5) days of accrued but unused paid time off, on the Termination Date.

b.Transition Services.During the Consulting Period (as defined in the above Recitals), Employee agrees that Employee will provide consulting services to the Company. Employee will perform tasks as agreed upon pursuant to the Consulting Agreement and assigned in good faith and to the best of Employee’s abilities (including, without limitation, assisting the Company with transitioning Employee’s responsibilities).  

c.Payments in Lieu of Healthcare Reimbursement.  The Company agrees to pay Employee a total of Seventeen Thousand Two Hundred and Ninety Dollars ($17,290), intended to assist Employee in defraying Employee’s out-of-pocket healthcare costs, at a rate of One Thousand Three Hundred and Thirty Dollars ($1,330) per month, less applicable withholdings, for thirteen (13) months from the Termination Date.  The payments to be made pursuant to the prior sentence will commence no later than on the first business day following the sixtieth (60^th) day following the Termination Date, with the first payment to include the payments due and owing prior to such first payment date but for the application of this sentence. For purposes of clarity, Employee is not obligated to use these funds for healthcare costs.

d.Stock; Forfeiture of Time-Based Options.  The Parties agree that Employee holds no stock options or other Company equity awards other than the Options indicated on Schedule 1. Notwithstanding any contrary provision of this Agreement or the Stock Agreements, as of the Effective Date, Employee agrees to permanently forfeit the portion of each Time-Based Option that is or was unvested as of the Termination Date.  “Time-Based Option” means each Option other than the Performance-Based Option.  “Performance-Based Option” means the Option to purchase 49,000 shares granted to Employee on August 12, 2020.  As a result, the Parties agree that for purposes of determining the number of shares of the Company’s common stock that Employee is entitled to purchase from the Company pursuant to the exercise of outstanding Time-Based Options, Employee will be considered to have vested only up to and including the Termination Date. The Company agrees that Employee’s Performance-Based Options will remain outstanding and eligible to vest through the

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Consulting Period while Employee remains in service to the Company (or any subsidiary of the Company) in accordance with the terms of the related Stock Agreements.  Notwithstanding the foregoing, in the event of a Corporate Transaction (as defined in the 2015 Plan) that occurs during the Consulting Period while Employee remains in service to the Company, one hundred percent (100%) of the then unvested shares subject to the then-outstanding Performance-Based Option will vest in full as of immediately prior to such Corporate Transaction.  The foregoing constitutes an amendment to each Option. The exercise of Employee’s vested Options and shares acquired thereunder shall continue to be governed by the terms and conditions of the applicable Stock Agreements as modified by this Agreement. For the avoidance of doubt, Employee acknowledges that Employee will not be granted additional Company equity awards during the Consulting Period. Employee acknowledges that pursuant to the Internal Revenue Code of 1986, as amended (the “Code”), 3 months immediately after the Termination Date, any Options that remain outstanding and which qualify as an “incentive stock option” (an “ISO”) under Section 422 of the Code as of the Termination Date shall, immediately following such 3-month period, automatically cease to be treated as an ISO and shall instead thereafter be treated for tax purposes a nonstatutory stock option (“NSO”), to the extent any such ISOs remain outstanding, do not cease to be treated as an ISO sooner, and are not exercised within such 3-month period.  Employee acknowledges that for each NSO held by Employee, upon exercise, such NSO shall be subject to all applicable tax withholdings, which shall be Employee’s sole responsibility. Employee agrees and acknowledges that Employee is solely responsible for keeping track of the relevant exercise period applicable to each Option or any deadline to exercise any ISOs, and that the Company is not responsible for reminding Employee of such periods or their expiration.  For the avoidance of doubt, Employee’s Service (as defined in the 2015 Plan) shall be considered to terminate as of the Service Separation Date for purposes of determining the time period in which Employee may exercise his vested Options.

e.Retirement.  The Company shall process the termination of Employee’s employment as a retirement, and shall represent that Employee retired from Employee’s employment in any internal or external announcements and to any potential future employer who contacts the Company’s human resources department and requests confirmation of this information. Notwithstanding the foregoing, the Company agrees not to contest or dispute any unemployment insurance claim Employee files, and shall report to any unemployment insurance agency that the Company terminated Employee and not contest Employee’s receipt of unemployment benefits. The Company further agrees that the CEO will provide positive oral references to support Employee in seeking future consulting or employment opportunities.

f.Acknowledgement. Employee acknowledges that without this Agreement, Employee is otherwise not entitled to the consideration listed in this Section 1. Employee further acknowledges that the consideration provided under this Agreement meets and exceeds any separation-related obligations to Employee under the Employment Agreement.  

2.Benefits.  Employee’s health insurance benefits ceased immediately at the end of the day on the Termination Date, subject to Employee’s right to continue Employee’s health insurance under COBRA. Employee’s participation in all benefits and incidents of employment, including, but not limited to, vesting in stock options, and the accrual of bonuses, vacation, and paid time off, ceased as of the Termination Date.

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3.Payment of Salary and Receipt of All Benefits.  Employee acknowledges and represents that, other than the consideration set forth in this Agreement, the Company has paid or provided all salary, wages, bonuses, accrued vacation/paid time off, premiums, leaves, housing allowances, relocation costs, interest, severance, outplacement costs, fees, reimbursable expenses, commissions, stock, stock options, vesting, and any and all other benefits and compensation due to Employee.

4.Release of Claims.  Employee agrees that the foregoing consideration represents settlement in full of all outstanding obligations owed to Employee by the Company and its current and former officers, directors, employees, agents, investors, attorneys, shareholders, administrators, affiliates, benefit plans, plan administrators, professional employer organization or co-employer, insurers, trustees, divisions, subsidiaries, predecessor and successor corporations, and assigns (collectively, the “Releasees”). Employee, on Employee’s own behalf and on behalf of Employee’s respective heirs, family members, executors, agents, and assigns, hereby and forever releases the Releasees from, and agrees not to sue concerning, or in any manner to institute, prosecute, or pursue, any claim, complaint, charge, duty, obligation, demand, or cause of action relating to any matters of any kind, whether presently known or unknown, suspected or unsuspected, that Employee may possess against any of the Releasees arising from any omissions, acts, facts, or damages that have occurred up until and including the date Employee signs this Agreement, including, without limitation:

a.any and all claims relating to or arising from Employee’s employment relationship with the Company and the termination of that relationship;

b.any and all claims relating to, or arising from, Employee’s right to purchase, or actual purchase of shares of stock of the Company, including, without limitation, any claims for fraud, misrepresentation, breach of fiduciary duty, breach of duty under applicable state corporate law, and securities fraud under any state or federal law;

c.any and all claims for wrongful discharge of employment, termination in violation of public policy, discrimination, harassment, retaliation, breach of contract (both express and implied), breach of covenant of good faith and fair dealing (both express and implied), promissory estoppel, negligent or intentional infliction of emotional distress, fraud, negligent or intentional misrepresentation, negligent or intentional interference with contract or prospective economic advantage, unfair business practices, defamation, libel, slander, negligence, personal injury, assault, battery, invasion of privacy, false imprisonment, conversion, and disability benefits;

d.any and all claims for violation of any federal, state, or municipal statute, including, but not limited to, Title VII of the Civil Rights Act of 1964; the Civil Rights Act of 1991; the Rehabilitation Act of 1973; the Americans with Disabilities Act of 1990; the Equal Pay Act; the Fair Labor Standards Act; the Fair Credit Reporting Act; the Age Discrimination in Employment Act of 1967; the Older Workers Benefit Protection Act; the Employee Retirement Income Security Act of 1974; the Worker Adjustment and Retraining Notification Act; the Family and Medical Leave Act; the Uniformed Services Employment and Reemployment Rights Act; the Massachusetts Law Prohibiting Unlawful Discrimination; the Massachusetts Wage Payment Act; the Massachusetts

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Discriminatory Wage Rates Penalized Law; the Massachusetts Equal Rights Law; the Massachusetts Violation of Constitutional Rights Law; the Massachusetts Family and Medical Leave Law; the Massachusetts Wage Act; and the Massachusetts Minimum Fair Wage Law;  

e.any and all claims for violation of the federal or any state constitution;

f.any and all claims arising out of any other laws and regulations relating to employment or employment discrimination;

g.any claim for any loss, cost, damage, or expense arising out of any dispute over the nonwithholding or other tax treatment of any of the proceeds received by Employee as a result of this Agreement; and

h.any and all claims for attorneys’ fees and costs.

Employee agrees that the release set forth in this section shall be and remain in effect in all respects as a complete general release as to the matters released.  This release does not extend to any obligations incurred under this Agreement.  This release does not release claims that cannot be released as a matter of law, including any Protected Activity (as defined below).  This release does not extend to any right Employee may have to unemployment compensation benefits or workers’ compensation benefits.  Employee represents that Employee has made no assignment or transfer of any right, claim, complaint, charge, duty, obligation, demand, cause of action, or other matter waived or released by this Section. Further, this release does not extend to rights Employee has to indemnification and defense, vested benefits, and rights set out in the Consulting Agreement.

5.Acknowledgment of Waiver of Claims under ADEA. Employee acknowledges that Employee is waiving and releasing any rights Employee may have under the Age Discrimination in Employment Act of 1967 ("ADEA"), and that this waiver and release is knowing and voluntary. Employee agrees that this waiver and release does not apply to any rights or claims that may arise under the ADEA after the date Employee signs this Agreement. Employee acknowledges that the consideration given for this waiver and release is in addition to anything of value to which Employee was already entitled. Employee further acknowledges that Employee has been advised by this writing that: (a) Employee should consult with an attorney prior to executing this Agreement; (b) Employee has at least twenty-one (21) days or until March 21, 2022, within which to consider this Agreement; (c) Employee has seven (7) days following Employee’s execution of this Agreement to revoke this Agreement; (d) this Agreement shall not be effective until after the revocation period has expired; and (e) nothing in this Agreement prevents or precludes Employee from challenging or seeking a determination in good faith of the validity of this waiver under the ADEA, nor does it impose any condition precedent, penalties, or costs for doing so, unless specifically authorized by federal law. In the event Employee signs this Agreement and returns it to the Company in less than the 21-day period identified above, Employee hereby acknowledges that Employee has knowingly and voluntarily chosen to waive the time period allotted for considering this Agreement. Employee acknowledges and understands that revocation must be accomplished by a written notification to the person executing this Agreement on the Company’s behalf that is received prior to the Transition Agreement Effective Date. The Parties agree that changes, whether material or immaterial, do not restart the running of the

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21-day period.

6.No Pending or Future Lawsuits.  Employee represents that Employee has no lawsuits, claims, or actions pending in Employee’s name, or on behalf of any other person or entity, against the Company or any of the other Releasees. Employee also represents that Employee does not intend to bring any claims on Employee’s own behalf or on behalf of any other person or entity against the Company or any of the other Releasees.

7.Unknown Claims.  Employee acknowledges that Employee is familiar with the principle that a general release does not extend to claims that the releasing party does not know or suspect to exist in his or her favor at the time of executing the release, which, if known by them, would have materially affected their settlement with the released party. Employee, being aware of said principle, agrees to expressly waive any rights Employee may have to that effect, as well as under any other statute or common law principles of similar effect, unless excluded from the release above.

8.Trade Secrets and Confidential Information/Company Information.  Employee agrees that Employee will not disclose or use the Company’s trade secrets and confidential and proprietary information, and that Employee will continue to abide by the terms of the Confidentiality Agreement.

9.Trade Secrets and Confidential Information/Company Property.  Employee acknowledges that, separate from this Agreement, Employee remains under continuing obligations to the Company under the Confidentiality Agreement, including the provisions therein regarding nondisclosure of the Company’s trade secrets and confidential and proprietary information. Employee’s signature below constitutes Employee’s certification under penalty of perjury that Employee has returned all documents and other items provided to Employee by the Company (with the exception of a copy of the Employee Handbook and personnel documents specifically relating to Employee), developed or obtained by Employee in connection with Employee’s employment with the Company, or otherwise belonging to the Company.  Notwithstanding the foregoing, Employee may retain his Company-provided laptop and Company-provided cell phone during the Consulting Period for use in performing the Consulting Services and for no other purpose.  Employee will be expected to return both the laptop and cell phone immediately upon expiration or termination of the Consulting Agreement.

10.No Cooperation.  Subject to the Protected Activity Not Prohibited section, Employee agrees that Employee will not knowingly encourage, counsel, or assist any attorneys or their clients in the presentation or prosecution of any disputes, differences, grievances, claims, charges, or complaints by any third party against any of the Releasees, unless under a subpoena or other court order to do so or upon written request from an administrative agency or the legislature or as related directly to the ADEA waiver in this Agreement. Employee agrees both to immediately notify the Company upon receipt of any such subpoena or court order or written request from an administrative agency or the legislature, and to furnish, within three (3) business days of its receipt, a copy of such subpoena or other court order or written request from an administrative agency or the legislature. If approached by anyone for counsel or assistance in the presentation or prosecution of any disputes, differences, grievances, claims, charges, or complaints against any of the Releasees, Employee shall state no more than that Employee cannot provide counsel or assistance.

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11.Protected Activity Not Prohibited.  Employee understands that nothing in this Agreement shall in any way limit or prohibit Employee from engaging in any Protected Activity. Protected Activity includes: (i) filing and/or pursuing a charge, complaint, or report with, or otherwise communicating, cooperating, or participating in any investigation or proceeding that may be conducted by any federal, state or local government agency or commission, including the Securities and Exchange Commission, the Equal Employment Opportunity Commission, the Occupational Safety and Health Administration, and the National Labor Relations Board (“Government Agencies”); and/or (ii) discussing or disclosing information about unlawful acts in the workplace, such as harassment or discrimination or any other conduct that Employee has reason to believe is unlawful. Employee understands that in connection with such Protected Activity, Employee is permitted to disclose documents or other information as permitted by law, without giving notice to, or receiving authorization from, the Company. Notwithstanding the foregoing, Employee agrees to take all reasonable precautions to prevent any unauthorized use or disclosure of any Company trade secrets, proprietary information, or confidential information that does not involve unlawful acts in the workplace or the activity otherwise protected herein. Employee further understands that Protected Activity does not include the disclosure of any Company attorney-client privileged communications or attorney work product. Any language in the Confidentiality Agreement regarding Employee’s right to engage in Protected Activity that conflicts with, or is contrary to, this section is superseded by this Agreement. In addition, pursuant to the Defend Trade Secrets Act of 2016, Employee is notified that an individual will not be held criminally or civilly liable under any federal or state trade secret law for the disclosure of a trade secret that (i) is made in confidence to a federal, state, or local government official (directly or indirectly) or to an attorney solely for the purpose of reporting or investigating a suspected violation of law, or (ii) is made in a complaint or other document filed in a lawsuit or other proceeding, if (and only if) such filing is made under seal. In addition, an individual who files a lawsuit for retaliation by an employer for reporting a suspected violation of law may disclose the trade secret to the individual’s attorney and use the trade secret information in the court proceeding, if the individual files any document containing the trade secret under seal and does not disclose the trade secret, except pursuant to court order.

12.Nondisparagement.  Subject to the Protected Activity Not Prohibited section, Employee agrees to refrain from any disparagement, defamation, libel, or slander of any of the Releasees, and agrees to refrain from any tortious interference with the contracts and relationships of any of the Releasees. Employee shall direct any inquiries by potential future employers to the Company’s human resources department, which shall use reasonable, good faith efforts to provide only the Employee’s last position and dates of employment.

13.Breach.  In addition to the rights provided in the “Attorneys’ Fees” section below, Employee acknowledges and agrees that any material breach of this Agreement, unless such breach constitutes a legal action by Employee challenging or seeking a determination in good faith of the validity of the waiver herein under the ADEA, or of any provision of the Confidentiality Agreement shall entitle the Company immediately to recover and/or cease providing the consideration provided to Employee under this Agreement and to obtain damages, except as provided by law.  

14.No Admission of Liability.  Employee understands and acknowledges that with respect to all claims released herein, this Agreement constitutes a compromise and settlement of any and all actual or potential disputed claims by Employee unless such claims were explicitly not released by the release in this Agreement. No action taken by the Company hereto, either previously or in connection with this Agreement, shall be deemed or construed to be (a) an admission of the truth or falsity of any actual or potential claims or (b) an acknowledgment or admission by the Company of any fault or liability whatsoever to Employee or to any third party.

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15.Costs.  The Parties shall each bear their own costs, attorneys’ fees, and other fees incurred in connection with the preparation of this Agreement.

16.ARBITRATION.  THE PARTIES AGREE THAT ANY AND ALL DISPUTES ARISING OUT OF THE TERMS OF THIS TRANSITION AGREEMENT, THEIR INTERPRETATION, AND ANY OF THE MATTERS HEREIN RELEASED, SHALL BE SUBJECT TO ARBITRATION IN SUFFOLK COUNTY, MASSACHUSETTS BEFORE THE JUDICIAL ARBITRATION AND MEDIATION SERVICE (“JAMS”) UNDER ITS COMPREHENSIVE ARBITRATION RULES (“JAMS RULES”) AND MASSACHUSETTS LAW.  THE ARBITRATOR MAY GRANT INJUNCTIONS AND OTHER RELIEF IN SUCH DISPUTES.  THE ARBITRATOR SHALL ADMINISTER AND CONDUCT ANY ARBITRATION IN ACCORDANCE WITH MASSACHUSETTS LAW, AND THE ARBITRATOR SHALL APPLY SUBSTANTIVE AND PROCEDURAL MASSACHUSETTS LAW TO ANY DISPUTE OR CLAIM, WITHOUT REFERENCE TO ANY CONFLICT-OF-LAW PROVISIONS OF ANY JURISDICTION.  TO THE EXTENT THAT THE JAMS RULES CONFLICT WITH MASSACHUSETTS LAW, MASSACHUSETTS LAW SHALL TAKE PRECEDENCE.  THE DECISION OF THE ARBITRATOR SHALL BE FINAL, CONCLUSIVE, AND BINDING ON THE PARTIES TO THE ARBITRATION.  THE PARTIES AGREE THAT THE PREVAILING PARTY IN ANY ARBITRATION SHALL BE ENTITLED TO INJUNCTIVE RELIEF IN ANY COURT OF COMPETENT JURISDICTION TO ENFORCE THE ARBITRATION AWARD.  THE PARTIES TO THE ARBITRATION SHALL EACH PAY HALF THE COSTS AND EXPENSES OF SUCH ARBITRATION, AND EACH PARTY SHALL SEPARATELY PAY FOR ITS RESPECTIVE COUNSEL FEES AND EXPENSES; PROVIDED, HOWEVER, THAT THE ARBITRATOR SHALL AWARD ATTORNEYS’ FEES AND COSTS TO THE PREVAILING PARTY, EXCEPT AS PROHIBITED BY LAW.  THE PARTIES AGREE THAT PUNITIVE DAMAGES SHALL BE UNAVAILABLE IN ARBITRATION.  THE PARTIES HEREBY AGREE TO WAIVE THEIR RIGHT TO HAVE ANY DISPUTE BETWEEN THEM RESOLVED IN A COURT OF LAW BY A JUDGE OR JURY.  NOTWITHSTANDING THE FOREGOING, THIS SECTION WILL NOT PREVENT EITHER PARTY FROM SEEKING INJUNCTIVE RELIEF (OR ANY OTHER PROVISIONAL REMEDY) FROM ANY COURT HAVING JURISDICTION OVER THE PARTIES AND THE SUBJECT MATTER OF THEIR DISPUTE RELATING TO THIS TRANSITION AGREEMENT AND THE AGREEMENTS INCORPORATED HEREIN BY REFERENCE.  SHOULD ANY PART OF THE ARBITRATION AGREEMENT CONTAINED IN THIS PARAGRAPH CONFLICT WITH ANY OTHER ARBITRATION AGREEMENT BETWEEN THE PARTIES, THE PARTIES AGREE THAT THIS ARBITRATION AGREEMENT SHALL GOVERN.

17.Tax Consequences.  The Company makes no representations or warranties with respect to the tax consequences of the payments and any other consideration provided to Employee or made on Employee’s behalf under the terms of this Agreement; provided, however, that the Company is responsible for accurately withholding from amounts payable under Section 1 hereunder in accordance with applicable laws. Employee agrees and understands that Employee is responsible for payment, if any, of local, state, and/or federal taxes on the payments and any other consideration provided hereunder by the Company and any penalties or assessments thereon. Employee further agrees to indemnify and hold the Releasees harmless from any claims, demands, deficiencies, penalties, interest, assessments, executions, judgments, or recoveries by any government agency against the Company for any amounts claimed due on account of (a) Employee’s failure to pay or delayed payment of federal or state taxes, or (b) damages sustained by the Company by reason of any such claims, including attorneys’ fees and costs. The Parties agree and acknowledge that the payments made pursuant to Section 1 of this Agreement are not related to sexual harassment or sexual abuse and not intended to fall within the scope of 26 U.S.C. Section 162(q).

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18.Section 409A.  It is intended that this Agreement comply with, or be exempt from, Code Section 409A and the final regulations and official guidance thereunder (“Section 409A”) so that none of the payments and benefits to be provided hereunder will be subject to the additional tax imposed under Section 409A, and any ambiguities herein will be interpreted to so comply and/or be exempt from Section 409A. Each payment and benefit to be paid or provided under this Agreement is intended to constitute a series of separate payments for purposes of Section 1.409A-2(b)(2) of the Treasury Regulations. Cash payments under Section 1 of this Agreement will be made no later than March 15, 2023. The Company and Employee will work together in good faith to consider either (i) amendments to this Agreement; or (ii) revisions to this Agreement with respect to the payment of any awards, which are necessary or appropriate to avoid imposition of any additional tax or income recognition prior to the actual payment to Employee under Section 409A. In no event will the Releasees have any obligation to reimburse or indemnify Employee or any other person for any taxes or costs that may be imposed on Employee or any other person as a result of Section 409A. In no event will Employee have discretion to determine the taxable year of payment of any separation-related payments. For the avoidance of doubt, the Company and Employee acknowledge that the intent and expectation of the Parties is that, following the Termination Date, Employee’s services to the Company will permanently decrease to no more than twenty percent (20%) of the average level of bona fide services performance by Employee over the immediately preceding thirty-six (36)-month period, and therefore that the Termination Date is a “separation from service” of Employee for purposes of Section 409A.

19.Authority.  The Company represents and warrants that the undersigned has the authority to act on behalf of the Company and to bind the Company and all who may claim through it to the terms and conditions of this Agreement. Employee represents and warrants that Employee has the capacity to act on Employee’s own behalf and on behalf of all who might claim through Employee to bind them to the terms and conditions of this Agreement. Each Party warrants and represents that there are no liens or claims of lien or assignments in law or equity or otherwise of or against any of the claims or causes of action released herein.

20.Severability.  In the event that any provision or any portion of any provision hereof or any surviving agreement made a part hereof becomes or is declared by a court of competent

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jurisdiction or arbitrator to be illegal, unenforceable, or void, this Agreement shall continue in full force and effect without said provision or portion of provision.

21.Attorneys’ Fees.  Except with regard to a legal action challenging or seeking a determination in good faith of the validity of the waiver herein under the ADEA, in the event that either Party brings an action to enforce or effect its rights under this Agreement, the prevailing Party shall be entitled to recover its costs and expenses, including the costs of mediation, arbitration, litigation, court fees, and reasonable attorneys’ fees incurred in connection with such an action.

22.Additional Acknowledgement; Entire Agreement.  The Parties agree that the consideration payable under this Agreement will remain subject to Section 7(c) (“Excise Tax”) of the Original Employment Agreement, (the “Surviving Section”) and such Section is specifically incorporated by reference into this Agreement. This Agreement represents the entire agreement and understanding between the Company and Employee concerning the subject matter of this Agreement and Employee’s employment with and separation from the Company and the events leading thereto and associated therewith, and supersedes and replaces any and all prior agreements and understandings, including but not limited to the Employment Agreement, concerning the subject matter of this Agreement and Employee’s relationship with the Company, with the exception of the Confidentiality Agreement and Consulting Agreement, the Surviving Section, and the Stock Agreement, except as otherwise modified or superseded herein.  This Agreement is binding on the Company’s successors and assigns.   If Employee dies before receiving his full severance payment, the balance of the payments will be made to Employee’s estate or beneficiaries.  

23.No Oral Modification.  This Agreement may only be amended in a writing signed by Employee and the Company’s Chief Executive Officer.

24.Governing Law.  This Agreement shall be governed by the laws of the State of Massachusetts, without regard for choice-of-law provisions. Employee consents to personal and exclusive jurisdiction and venue in the State of Massachusetts.

25.Transition Agreement Effective Date.  Employee understands that this Agreement shall be null and void if not executed by Employee within twenty-one (21) days. Each Party has seven (7) days after that Party signs this Agreement to revoke it. This Agreement will become effective on the eighth (8th) day after Employee signed this Agreement, so long as it has been signed by the Parties and has not been revoked by either Party before that date (the “Transition Agreement Effective Date”).

26.Counterparts.  This Agreement may be executed in counterparts and each counterpart shall be deemed an original and all of which counterparts taken together shall have the same force and effect as an original and shall constitute an effective, binding agreement on the part of each of the undersigned.  The counterparts of this Agreement may be executed and delivered by facsimile, photo, email PDF, or other electronic transmission or signature.

[THE REMAINDER OF THIS PAGE IS INTENTIONALLY LEFT BLANK; SIGNATURE PAGE FOLLOWS]

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27.Voluntary Execution of Agreement.  Employee understands and agrees that Employee executed this Agreement voluntarily and without any duress or undue influence on the part or behalf of the Company or any third party, with the full intent of releasing all of Employee’s claims against the Company and any of the other Releasees, except as specifically excluded above. Employee acknowledges that:

(a)Employee has read this Agreement;

IN WITNESS WHEREOF, the Parties have executed this Agreement on the respective dates set forth below.

MARK KOWALSKI, an individual

Dated:  March 21, 2022, /s/ Mark Kowalski

Mark Kowalski

SIERRA ONCOLOGY, INC.

Dated:  March 22, 2022,By /s/ Dr. Stephen Dilly

Dr. Stephen Dilly

Chief Executive Officer

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Exhibit 10.1

SCHEDULE 1

EMPLOYEE’S OPTIONS

Exhibit 10.2

CONSULTING AGREEMENT

THIS CONSULTING AGREEMENT (this “Agreement”) is made effective on the last signature date below (the “Effective Date”), between Sierra Oncology, Inc., a Delaware corporation, having offices at 1820 Gateway Drive, Suite 110 San Mateo, CA 94404 U.S.A. the “Company”), and Mark Kowalski, MD, PhD, an individual, whose address is 10 Priscilla Lane, Winchester, MA, United States (“Consultant”).

Background

Whereas, Company is a late-stage biopharmaceutical company focused on unmet needs in myelofibrosis;

Whereas, Consultant desires to provide the Services described herein to Company subject to the terms and conditions below.

Terms and Conditions

Now, Therefore, in consideration of the foregoing and the terms, conditions and covenants hereinafter set forth, Company and Consultant agree as follows:

1.Certain Definitions.  Capitalized terms used in this Agreement and not otherwise defined shall have the following meanings:

(a)“Company Documents and Materials” means documents or other media, whether in tangible or intangible form, that contain or embody Proprietary Information or any other information concerning the business, operations or plans of Company, whether such documents or media have been prepared by Consultant or by others.  Company Documents and Materials include, without limitation, blueprints, drawings, photographs, charts, graphs, notebooks, customer lists, computer disks, tapes or printouts, sound recordings and other printed, electronic, typewritten or handwritten documents or information, sample products, prototypes and models.

(b)“Inventions” means, without limitation, all software programs or subroutines, source or object code, algorithms, improvements, inventions, works of authorship, trade secrets, scientific results, biological systems, product formulations, compositions of matter, methods, cell lines, technology, designs, formulas, ideas, processes, techniques, know-how and data, whether or not patentable or copyrightable, made or discovered or conceived or reduced to practice or developed by Consultant during the Consulting Period, either alone or jointly with others.

(c)“Proprietary Information” means information that was or will be developed, created, or discovered by or on behalf of Company, or which became or will become known by, or was or is conveyed to Company, which has commercial value in Company’s business, including, without limitation, information about Inventions, business

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and product development plans, customer lists, terms of compensation and performance levels of Company employees and consultants, Company customers and other information concerning Company’s actual or anticipated business, research or development, or which is received in confidence by or for Company from any other person or entity.

(d)“Services” means the consulting services to be performed by Consultant on behalf of Company set forth on Exhibit A, attached hereto.

2.Services.  Company hereby engages Consultant, and Consultant accepts such engagement, to perform the Services.  The Consultant shall perform the Services in a timely and professional manner.

3.Term.  The term of this Agreement shall commence on March 10, 2022 and unless earlier terminated as provided in this Section 3, shall expire at the end of the business day on June 30, 2023 (such period the “Consulting Period”).  Company may terminate this Agreement immediately and without prior notice if Consultant refuses to or is unable to perform the Services, or is in breach of any material provision of this Agreement. Either party may terminate this Agreement immediately upon occurrence of any of the following events: (a) the dissolution, voluntary or involuntary bankruptcy of either party, or assignment by either party of all or substantially all of its assets for the benefit of creditors; or (b) embezzlement, fraud or deceit in the performance of the other party’s obligations hereunder.  Notwithstanding the termination of this Agreement, any liability or obligation of either party which may have accrued prior to such termination shall continue in full force and effect.

4.Compensation.  

Company agrees to pay Consultant the compensation described in Exhibit A for Consultant’s performance of the Services.

5.Expenses.  Company shall reimburse Consultant for reasonable, documented and actual expenses incurred by Consultant in connection with the performance of the Services; provided, however, that Consultant obtains the prior written approval of Company.  Company shall make any such reimbursement within thirty (30) days after receipt of an invoice therefor, accompanied by receipts, vouchers or other written evidence of the expenses incurred.  All invoices for expenses shall be sent to Company electronically at accountspayable@sierraoncology.com.  Company shall have no obligation to reimburse Consultant for expenses that were not approved in advance in writing by Company.

6.Confidentiality of Proprietary Information.

(a)Nature of Information.  Consultant understands that Company possesses and will possess Proprietary Information which is important to its business.  

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Consultant understands that Consultant’s engagement creates a relationship of confidence and trust between Company and Consultant with respect to Proprietary Information.

(b)Property of Company.  Consultant acknowledges and agrees that all Company Documents and Materials, Proprietary Information and all patents, patent rights, copyrights, trade secret rights, trademark rights and other rights (including, without limitation, intellectual property rights) anywhere in the world in connection therewith is and shall be the sole property of Company.  Consultant hereby assigns to Company any and all rights, title and interest Consultant may have or acquire in the Proprietary Information or any Company Documents and Materials.

(c)Confidentiality.  At all times, both during the term of Consultant’s engagement by Company and for five (5) years after its termination, Consultant shall keep in confidence and trust and shall not use or disclose any Proprietary Information or anything relating to it without the prior written consent of Company, except as may be necessary in the ordinary course of performing the Services; provided, however, that Consultant shall have no such obligation with respect to Proprietary Information that (i) was already known to Consultant at the time of its disclosure to Consultant by or on behalf of the Company, (ii) at the time of disclosure to Consultant was generally available to the public or otherwise in the public domain, (iii) subsequent to such disclosure becomes generally available to the public without fault on Consultant’s part, or (iv) otherwise becomes known to Consultant on a non-confidential basis from another source not bound by a confidentiality agreement with Company.

(d)Compelled Disclosure.  In the event that Consultant is requested in any proceeding to disclose any Proprietary Information, Consultant shall give Company prompt notice of such request so that Company may seek an appropriate protective order.  If, in the absence of a protective order, Consultant is nonetheless compelled by order or subpoena of any court of tribunal of competent jurisdiction to disclose Proprietary Information, Consultant may disclose such information without liability hereunder; provided, however, that Consultant gives Company notice of the Proprietary Information to be disclosed as far in advance of its disclosure as is practicable and uses Consultant’s best efforts to obtain assurances that confidential treatment will be accorded to such Proprietary Information.

(e)Records.  Consultant agrees to make and maintain adequate and current written records, in a form specified by Company, of all Inventions, Company Documents and Materials and other trade secrets and works of authorship assigned or to be assigned to Company pursuant to this Agreement.

(f)Handling of Company Documents and Materials.  Consultant agrees that during Consultant’s engagement by Company, Consultant shall not remove any Company Documents and Materials from the business premises of Company or deliver any Company Documents and Materials to any person or entity outside Company, except as

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Consultant is required to do in connection with performing the Services.  Consultant further agrees that, immediately upon the termination of Consultant’s engagement by Company for any reason, or during the term of Consultant’s engagement if so requested by Company, Consultant shall return to Company all Company Documents and Materials, apparatus, equipment and other physical property, or any reproduction of such property, excepting only (i) Consultant’s personal copies of records relating to Consultant’s compensation; (ii) Consultant’s personal copies of any materials previously distributed generally to stockholders of Company; and (iii) Consultant’s copy of this Agreement and other agreements he has with the Company.

7.Inventions.

(a)Disclosure.  Consultant shall promptly disclose in writing to Company all Inventions made during the term of Consultant’s engagement by Company within the scope of the Services.  Consultant shall also disclose to Company all Inventions made, discovered, conceived, reduced to practice, or developed by Consultant within six (6) months after the termination of Consultant’s engagement with Company which resulted, in whole or in part, from the Services.  Such disclosures shall be received by Company in confidence, to the extent such Inventions are not assigned to Company pursuant to subsection (b) below, and do not extend the assignments made in such subsection.

(b)Assignment of Inventions to Company.  During the Consulting Period, Consultant agrees to assign and hereby assigns to Company all Inventions (together with all associated patents, patent rights, copyrights, trade secret rights, trademark rights and all other intellectual property) which Consultant makes, discovers, conceives, reduces to practice or develops (in whole or in part, either alone or jointly with others) within the scope of the Services to the maximum extent permitted by law.

(c)Prior Inventions.  If in the course of Consultant’s engagement with Company, Consultant incorporates into any work product resulting from the Services or a Company product, process or machine a prior Invention owned or controlled by Consultant, then Consultant hereby grants to Company a nonexclusive, royalty-free, irrevocable, perpetual, sublicensable, worldwide license to make, have made, modify, use, market, sell, offer for sale, import and distribute such prior Invention.

(d)Cooperation.  Consultant agrees to perform, during and after the term of Consultant’s engagement by Company, all acts deemed necessary or desirable by Company to permit and assist it, at Company’s expense, in further evidencing and perfecting the assignments made to Company under this Agreement and in obtaining, maintaining, defending and enforcing patents, patent rights, copyrights, trademark rights, trade secret rights or any other rights in connection with such Inventions and improvements thereto in any and all countries.  Such acts include, without limitation, execution of documents and assistance or cooperation in legal proceedings.  Consultant hereby

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irrevocably designates and appoints Company and its duly authorized officers and agents, as Consultant’s agents and attorney-in-fact, coupled with an interest, to act for and on Consultant’s behalf and in Consultant’s place and stead, to execute and file any documents, applications or related findings and to do all other lawfully permitted acts to further the purposes set forth above in this Section, including, without limitation, the perfection of assignment and the prosecution and issuance of patents, patent applications, copyright applications and registrations, trademark applications and registrations or other rights in connection with such Inventions and improvements thereto with the same legal force and effect as if executed by Consultant.

(e)Assignment or Waiver of Moral Rights.  Any assignment of copyright hereunder (and any ownership of a copyright as a work made for hire) includes all rights of paternity, integrity, disclosure and withdrawal and any other rights that may be known as or referred to as “moral rights” (collectively, “Moral Rights”).  To the extent such Moral Rights cannot be assigned under applicable law and to the extent allowed by the laws in the various countries where Moral Rights exist, Consultant hereby waives such Moral Rights and consents to any action of Company that would violate such Moral Rights in the absence of such consent.

8.Obligations and Representations.

(a)Compliance with Laws. Consultant represents that its performance of the Services shall comply, at Consultant’s own expense, with all applicable laws, ordinances, regulations and codes applicable to Consultant and the Services.

(b)Debarment. Consultant represents that Consultant is not under investigation by the United States Food and Drug Administration (the “FDA”) for debarment and is not debarred by the FDA pursuant to the Generic Drug Enforcement Act of 1992, as amended (21 U.S.C. § 301, et seq.). In addition, Consultant represents that Consultant has not engaged in any conduct or activity which could lead to any such debarment actions. Consultant agrees to immediately notify Company if, during the term of this Agreement, Consultant: (i) comes under investigation by the FDA for a debarment action; (ii) is debarred; or (iii) engages in any conduct or activity that could lead to debarment.

(c)Exclusion. Consultant represents that Consultant is not excluded from a federal health care program as outlined in Sections 1128 and 1156 of the Social Security Act, including, but not limited to, Medicare, Medicaid and the Civilian Health and Medical Program of the Uniformed Services. In addition, Consultant represents that Consultant has not engaged in any conduct or activity which could lead to any such exclusion actions. Consultant agrees to immediately notify Company if, during the term of this Agreement, Consultant: (i) is excluded from a state or federally funded healthcare program; or (ii) engages in any conduct or activity that could lead to exclusion.

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(d)Anti-Bribery / Anti-Corruption Statutes.

(i)“Government Official” shall mean any officer (elected or appointed) or employee of a government or public organization or institution, or a department, agency or instrumentality of any of the foregoing, any official of a political party or a candidate for political office, or anyone otherwise categorized as a Government Official under applicable law.

(ii)Consultant is aware of and understands that there are anti-bribery and anti-corruption statutes (including but not limited to the US Foreign Corrupt Practices Act and the UK Bribery Act) to which Company is subject that prohibit the payment or offering, giving, promising to give, or authorizing the giving of, directly or indirectly, anything of value to a Government Official (as defined herein), or any relative, business associate or employee thereof, for the purpose of obtaining or retaining any business under this Agreement or otherwise related to Company or inducing or influencing any governmental act or decision affecting Company. Consultant hereby agrees to refrain from any activity in connection with this Agreement that would constitute a violation by Consultant or Company of such anti-bribery and anti-corruption statutes, including sharing, directly or indirectly, any of the fees paid to Consultant under this Agreement with a Government Official. Similarly, Consultant shall not, directly or indirectly, request, accept, or agree to accept any item of value that could be seen as an attempt to compromise its independence of judgment or improperly influence a business decision.

(iii)Upon Company’s request, or should Company ever become the subject of an audit or investigation by a US, European or other governmental authority, including under any anti-boycott regulations, anti-bribery legislation, or related export legislation, Consultant agrees to cooperate fully with Company in connection with such investigation and to provide such information and records to Company with respect to Consultant’s activities under this Agreement as may be reasonably requested by Company.

(iv)Company may terminate this Agreement immediately in the event Consultant breaches any of the representations or covenants in this Section 8(d) or if Company learns that improper payments are being or have been made to Government Officials by Consultant with respect to Services performed on behalf of Company or any other company.

(e)Government Employee. Consultant represents that if Consultant is a federal, state or county government employee (as defined by the applicable entity), Consultant has obtained approval from an authorized representative of Consultant’s employer to enter into this Agreement and work on Company’s behalf as a consultant, and Consultant shall obtain any necessary prior approval from an authorized representative of Consultant’s employer for each and every activity performed on Company’s behalf in accordance with this Agreement. Consultant further agrees that upon Company’s request, Consultant shall provide Company with written confirmation of such approvals, signed by

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an authorized representative of Consultant’s employer.

(f)Insider Trading. Consultant acknowledges and agrees that: (a) Consultant is aware of the restrictions imposed by the United States federal securities laws and other applicable foreign and domestic laws on a person or entity possessing material non-public information about a public company; and (b) that Consultant will comply with such laws and will not trade on the basis of Proprietary Information, to the extent it constitutes material non-public information about the Company.

9.Non-Solicitation or Hire of Company Employees.  During the term of Consultant’s engagement by Company and for one (1) year thereafter, Consultant shall not encourage or solicit any employee of Company to leave Company for any reason or to accept employment with Consultant or any other entity.  As part of this restriction, Consultant shall not (a) interview or provide any input to any third party regarding any such employee during such time period, or (b) retain or hire in any capacity, either individually or for any person or entity by which Consultant may be engaged or with which Consultant may be affiliated, any person who is or was employed by Company at any time during the term of Consultant’s engagement by Company and six (6) months after the termination of such engagement.

10.Non-Solicitation of Non-Employees.  During the term of this Agreement and for one (1) year thereafter, Consultant shall not interfere with or attempt to impair the relationship between Company and any of its non-employee consultants and advisors, nor shall Consultant attempt, directly or indirectly, to solicit, entice, hire or otherwise induce any non-employee consultant or advisor of Company to terminate association with Company.

11.Non-Competition.  In this Section, “Competitive Activities” means any activities that directly compete with Company’s research studies on momelotinib and Company’s other compounds, and Company’s development and commercialization of its compounds. During the term of Consultant’s engagement , Consultant shall not, with or without consideration, render services in any capacity to any person, business, firm or corporation engaged in any Competitive Activities. Consultant shall not become interested in any such business involved in Competitive Activities, either directly or indirectly, as partner, stockholder, principal, member, employee, agent, trustee, consultant, or any other relationship or capacity; provided, however, that such restriction shall not apply with respect to a less than or equal to a one percent (1%) interest in any entity which is publicly traded and listed on a recognized securities exchange.

12.Arrangement Non-Exclusive.  Subject to Section 11, Company recognizes and acknowledges that Consultant may enter into agreements unrelated to this Agreement with entities other than Company.  

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13.Company Authorization for Publication.  Consultant shall not publish or present any of Company Proprietary Materials, Inventions or Company Documents and Materials without the prior written consent of Company.  Prior to Consultant’s submitting or disclosing for possible publication or dissemination outside Company any material prepared by Consultant that may incorporate information that concerns Company’s business or anticipated research, Consultant shall deliver a copy of such material to Company for review.  Within twenty (20) days following such submission, Company agrees to notify Consultant in writing whether Company believes such material contains any Proprietary Information, Inventions or Company Documents and Materials, and Consultant agrees to make such deletions and revisions as are requested by Company to protect its Proprietary Information, Inventions Company Documents and Materials.  Consultant further agrees to obtain the written consent of Company prior to any review of such material by persons outside Company.

14.Former Employer Information.  Consultant represents and warrants to Company that Consultant’s performance of all the terms of this Agreement and as a consultant of Company does not and shall not breach any agreement to keep in confidence any confidential or proprietary information, knowledge or data acquired by Consultant in confidence or in trust prior to Consultant’s engagement by Company, or violate the terms of any covenant not to compete between Consultant and any other person or entity.  Consultant shall not disclose to Company or induce Company to use any confidential or proprietary information or material belonging to any previous employers of Consultant or any other person or entity.  Consultant has not entered into and Consultant shall not enter into any agreement, either written or oral, in conflict herewith or in conflict with Consultant’s engagement with Company.  Consultant shall comply with the rules and regulations of Company.

15.Independent Contractor.  It is understood and agreed that Consultant is an independent contractor, is not an agent or employee of the Company, and is not authorized to act on behalf of the Company.  Consultant agrees not to hold himself, herself or itself out as, or give any person any reason to believe that she, he or it is, an employee, agent, joint venturer or partner of the Company.  Consultant will not be eligible for any employee benefits, nor will the Company make deductions from any amounts payable to Consultant for taxes or insurance (except to the extent the Company is required by law to do so).  All payroll and employment taxes, self-employment taxes, insurance, and benefits shall be the sole responsibility of Consultant.  Consultant is engaged in the business of consulting generally for other clients, and represents and warrants that Company is not Consultant’s sole client. Consultant retains the right (as limited in Sections 11 and 12) to provide services for others during the term of this Agreement and is not required to devote Consultant’s services exclusively for the Company.  Nothing in this Agreement is intended to allow Company to exercise control or direction over the manner or method by which Consultant performs the Services under the terms of Consultant’s engagement by

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Company. This Section applies equally to Consultant’s personnel performing hereunder (if Consultant is not a natural person).

16.Employment of Personnel.  Consultant may employ other persons to assist in the performance of the Services and shall be responsible for, and in full control of, the work of such personnel.  Consultant shall be solely responsible for the actions or omissions, for filing all necessary forms and returns, and for making all required payments to all relevant governmental authorities for itself and its agents and employees.

17.Maintenance of Records.  During the term of this Agreement and, until the expiration of two (2) years after the furnishing of the Services pursuant to this Agreement, Consultant shall make available, upon written request of Company or its designee, any records maintained by Consultant regarding any of the Services performed hereunder by Consultant.

18.No Authority to Bind.  Consultant shall have no power or authority to execute any agreements or contracts for or on behalf of Company nor to bind Company in any other manner.

19.Injunctive Relief.  Consultant acknowledges that breach of any of the provisions of this Agreement could cause Company irreparable injury for which no adequate remedy at law exists.  Accordingly, Company shall have the right, in addition to any other rights it may have, and by executing this Agreement Consultant hereby consents, to the entry in any court having jurisdiction of a temporary or permanent restraining order or injunction restraining or enjoining Consultant from any violation of this Agreement.  Consultant further agrees to waive, and to use Consultant’s best efforts to cause Consultant’s directors, officers, employees and agents, if any, to waive, any requirement for the securing or posting of any bond in connection with such remedy.

20.No Assignment.  This Agreement may not be assigned by either party without the written consent of the other party; provided, however, that Company must, without such consent, assign this Agreement and its rights and obligations hereunder in connection with the transfer or sale of all or substantially all of its business or assets related to this Agreement, or in the event of its merger, consolidation, change in control or other similar transaction.

21.Severability.  Consultant agrees that if one or more provisions of this Agreement are held to be unenforceable under applicable law, such provisions shall be excluded from this Agreement and the balance of the Agreement shall be interpreted as if such provision were so excluded and shall be enforceable in accordance with its terms.

22.Binding Effect.  This Agreement shall inure to the benefit of and be binding upon, the parties and their respective successors and permitted assigns.

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23.Amendment.  This Agreement may not be amended except by mutual written Agreement of the parties.

24.Notices.  All notices, requests, demands and other communications shall be in writing and shall be deemed to have been duly given or made if delivered by hand, in which case notice will be deemed effective upon receipt, or, if by mail by certified or registered mail, with postage prepaid to the address of such party set forth in the introductory paragraph of this Agreement or to such address directed by a party in writing, in which case notice will be deemed effective upon mailing.  The return receipt, the delivery receipt, or the affidavit of messenger will be deemed conclusive but not exclusive evidence of delivery; delivery will also be presumed at such time as delivery is refused by the addressee upon presentation.

25.Continuing Obligations. The provisions set forth in this Agreement that by their terms have continuing obligations, or that which logically, by their nature, are intended to survive, will survive termination or expiration of this Agreement. Such provisions include, but are not limited to, payment obligations, confidentiality, inventions, obligations and representations, publications, indemnification and choice of law. Final payment by Company will not constitute a waiver by Company of possible claims for continuing obligations on the part of Consultant.

26.Entire Agreement.  This Agreement shall constitute the entire agreement between the parties and supersedes any and all other written or oral agreements between Consultant and Company with respect to the subject matter of this Agreement.

27.Governing Law; Consent to Jurisdiction, Waiver of Jury Trial.  This Agreement shall be governed by and construed in accordance with the internal laws of the Commonwealth of Massachusetts, without regard to its principles of conflicts of laws. Each of the parties hereto irrevocably submits to the exclusive jurisdiction of the state and federal courts of the Commonwealth of Massachusetts for the purpose of any suit, action, proceeding or judgment relating to or arising out of this Agreement and the transactions contemplated hereby.  Service of process in connection with any such suit, action or proceeding may be served on each party hereto anywhere in the world by the same methods as are specified for the giving of notices under this Agreement. Each party hereto irrevocably waives any objection to the laying of venue of any such suit, action or proceeding brought in such courts and irrevocably waives any claim that any such suit, action or proceeding brought in any such court has been brought in an inconvenient forum.  EACH OF THE PARTIES HERETO WAIVES ANY RIGHT TO REQUEST A TRIAL BY JURY IN ANY LITIGATION WITH RESPECT TO THIS AGREEMENT AND REPRESENTS THAT COUNSEL HAS BEEN CONSULTED SPECIFICALLY AS TO THIS WAIVER.

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28.Counterparts.  This Agreement may be executed in one or more counterparts, each of which shall constitute an original, and all of which together shall constitute one and the same instrument.

Signatures on the Following Page

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In Witness Whereof, Company and Consultant have made this Agreement effective as of the date first set forth above.

Signature Page to Consulting Agreement

EXHIBIT A

SERVICES

Consultant shall provide Company with post-separation consulting services, as a former employee of Company, to assist with knowledge transition.

Company contact for Consultant: Dr. Stephen Dilly, Chief Executive Officer

Compensation

(a)Fees. In consideration of Consultant’s performance of the Services, Company shall pay Consultant an hourly fee of US$400.00. Consultant will be expected to perform the Services for no more than, on average, eight (8) hours per week.

(b)Payment. Company shall make payment within thirty (30) days after receipt of an invoice. All invoices for compensation under this Agreement shall reference the PO number to be provided by Company on execution of this Agreement and be sent to Company electronically at accountspayable@sierraoncology.com. On execution of this Agreement, Consultant shall submit a current applicable Internal Revenue Service (“IRS”) tax form (W-9, W-8BEN or W-8BEN-E) to Company.

(c)Section 409A.  In order to help prevent adverse tax consequences to Consultant under Section 409A (as defined below), in no event will any payment under this Exhibit A be made later than the later of (1) March 15th of the calendar year following the calendar year in which such payment was earned, or (2) the 15th day of the third (3rd) month following the end of the Company’s fiscal year in which such payment was earned.  All payments and benefits provided for under this Agreement are intended to be exempt from or otherwise comply with the requirements of Section 409A of the Internal Revenue Code of 1986, as amended (the “Code”), and the regulations and guidance thereunder (together, “Section 409A”), so that none of the payments and benefits to be provided hereunder will be subject to the additional tax imposed under Section 409A, and any ambiguities or ambiguous terms herein will be interpreted to be exempt or so comply. Each payment and benefit payable under this Agreement is intended to constitute a separate payment for purposes of Section 1.409A-2(b)(2) of the Treasury Regulations. In no event will the Company have any liability or obligation to reimburse, indemnify or hold harmless Consultant or any other person for any taxes or costs that may be imposed on or incurred by Consultant as a result of Section 409A.

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