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EXHIBIT 10.52


August 5, 2002



Kevin Helmbacher, Esq.
232 Pacific View Lane
Encinitas, CA 92024

Dear Kevin:

As you are aware, Corvas has had to reevaluate its ongoing research and
development efforts which has resulted in a Company-wide reduction in force.
Unfortunately, your position has been eliminated through this restructuring.

In consideration of your service to the Company and to assist you in your job
search, we are offering you a separation agreement which provides certain
benefits beyond those to which you are normally entitled.

This SEPARATION AGREEMENT ("Agreement") is made and entered into by and between
you and CORVAS INTERNATIONAL, INC. ("the Company"). You shall have seven days
following the date of this Agreement to consider and return a fully executed
original of the Agreement to the Company. This Agreement shall become effective
immediately upon execution by you (the "Effective Date").

NOW, THEREFORE, in consideration of the mutual promises and covenants contained
herein, it is hereby agreed by and between the parties hereto as follows:

1.       SEPARATION DATE. On July 31, 2002("Separation Date"), you shall cease
         to be an employee of the Company for all purposes.

2.       ACCRUED SALARY AND ACCRUED TIME OFF. On or about the Separation Date,
         the Company will pay you all accrued salary, and all accrued and unused
         vacation and paid personal leave (PPL), if any, subject to standard
         payroll deductions and withholdings. You are entitled to these payments
         regardless of whether or not you sign this Agreement.

3.       EXPENSE REIMBURSEMENT. Within thirty (30) business days of your
         Separation Date, you agree that you will submit your final documented
         expense reimbursement statement reflecting all business expenses you
         incurred prior to and including the Separation Date, if any, for which
         you seek reimbursement. The Company shall reimburse your expenses
         pursuant to Company policy and regular business practice.

4.       EMPLOYMENT SEARCH SUPPORT. Commencing on the Separation Date, the
         Company will provide you offsite employment search support through
         Drake Beam Morin, Inc. for a period of six months as outlined in
         Exhibit A attached hereto.


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5.       SEVERANCE PAYMENTS. In exchange for the promises and covenants set
         forth herein and in consideration thereof, the Company agrees to pay
         you severance equivalent to nine (9) months of pay at your current base
         salary, subject to standard payroll deductions and withholdings. The
         severance payments will be made in the form of continuing payments from
         the Effective Date through April 30, 2003 (the "Severance Period").
         These payments will be made on the Company's ordinary payroll dates,
         and will be subject to standard payroll deductions and withholdings.
         However, contributions to your 401(k) account, Section 125
         reimbursement account, supplemental or dependent life insurance or the
         Company's Employee Stock Purchase Plan will not be allowed.

6.       INSURANCE BENEFITS. During the Severance Period, medical, dental, and
         vision insurance coverage for you and your currently insured dependents
         will be extended at the Company's expense, however, the Company shall
         continue to deduct from your severance payments an amount equal to your
         current insurance benefit premium contribution. In the event you become
         eligible for benefits under another plan(s) prior to the expiration of
         the Severance Period, the Company shall no longer be obligated to pay
         such benefit premiums. It is your responsibility to notify the Company
         once you become eligible under another plan. To the extent provided by
         the federal COBRA law or, if appicable, state insurance laws, and by
         the Company's current group health insurance policies, you will be
         eligible to continue your health insurance benefits following the
         Severance Period at your own expense. Later you may be able to convert
         to an individual policy through the provider of the Company's health
         insurance, if you wish. You will be provided with a separate notice of
         your COBRA rights.

7.       STOCK OPTIONS. Pursuant to the Company's 1991 Incentive and
         Compensation Plan, and 2000 Equity Incentive Plan, vesting under any
         stock compensation award (e.g., incentive stock option, nonqualified
         stock option, or stock purchase agreement) from the Company shall cease
         on the Separation Date. Your rights to exercise any vested shares will
         be as set forth under the applicable plan and any Stock Option
         Agreements.

8.       OTHER COMPENSATION AND BENEFITS. Except as expressly provided herein,
         you acknowledge that you will not receive (nor are entitled to receive)
         any additional compensation, severance, stock options, stock or
         benefits from the Company.

9.       RETURN OF COMPANY PROPERTY. By the Separation Date, you will return to
         the Company all Company documents (and all copies thereof) and other
         Company property and materials in your possession, or control,
         including, but not limited to, Company files, notes, memoranda,
         correspondence, lists, drawings, records, plans and forecasts,
         financial information, personnel information, customer and customer
         prospect information, product development and pricing information,
         specifications, computer-recorded information, tangible property,
         equipment, credit cards, entry cards, identification badges and keys;
         and any materials of any kind which contain or embody any proprietary
         or confidential information of the Company (and all reproductions
         thereof).

10.      PROPRIETARY INFORMATION OBLIGATIONS. You acknowledge that nothing
         herein shall impair the covenants and obligations set forth in your
         Employment Agreement, a copy of which is attached hereto as Exhibit B.
         Pursuant to the Employment Agreement you understand that you must not
         use or disclose any confidential or proprietary information of the
         Company, among other things as required by the Employment Agreement.


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11.      NONSOLICITATION. You agree that for one (1) year following the
         Separation Date, you will not, either directly or through others,
         solicit or attempt to solicit any person (including any entity) who is
         then an employee, consultant or independent contractor of the Company
         to terminate his, her or its relationship with the Company in order to
         become an employee, consultant or independent contractor to or for any
         other person or entity.

12.      NON-DISPARAGEMENT. You and the Company agree that neither party will at
         any time disparage the other party, and the other party's officers,
         directors, employees, shareholders and agents, in any manner likely to
         be harmful to them or their business, business reputation or personal
         reputation; provided that each party shall respond accurately and fully
         to any questions, inquiry or request for information when required by
         legal process.

13.      CONFIDENTIALITY AND PUBLICITY. The existence of this Agreement and the
         provisions of this Agreement shall be held in strictest confidence by
         you and the Company and shall not be publicized or disclosed in any
         manner whatsoever; provided, however, that: (a) you may disclose this
         Agreement, in confidence to your immediate family; (b) the parties may
         disclose this Agreement in confidence to their respective attorneys,
         accountants, auditors, tax preparers, and financial advisors; (c) the
         Company may disclose this Agreement as necessary to fulfill standard or
         legally required corporate reporting or disclosure requirements; and
         (d) the parties may disclose this Agreement insofar as such disclosure
         may be necessary to enforce its terms or as otherwise required by law.

14.      YOUR RELEASE OF CLAIMS. Except as otherwise set forth in this
         Agreement, in exchange for the consideration provided to you by this
         Agreement that you are not otherwise entitled to receive, you hereby
         generally and completely release the Company and its directors,
         officers, employees, shareholders, partners, agents, attorneys,
         predecessors, successors, parent and subsidiary entities, insurers,
         affiliates, and assigns from any and all claims, liabilities and
         obligations, both known and unknown, that arise out of or are in any
         way related to events, acts, conduct, or omissions occurring prior to
         your signing this Agreement. This general release includes, but is not
         limited to: (1) all claims arising out of or in any way related to your
         employment with the Company or the termination of that employment; (2)
         all claims related to your compensation or benefits from the Company,
         including salary, bonuses, commissions, vacation pay, paid personal
         leave, expense reimbursements, severance pay, fringe benefits, stock,
         stock options, or any other ownership interests in the Company; (3) all
         claims for breach of contract, wrongful termination, and breach of the
         implied covenant of good faith and fair dealing; (4) all tort claims,
         including claims for fraud, defamation, emotional distress, and
         discharge in violation of public policy; and (5) all federal, state,
         and local statutory claims, including claims for discrimination,
         harassment, retaliation, attorneys' fees, or other claims arising under
         the federal Civil Rights Act of 1964 (as amended), the federal
         Americans with Disabilities Act of 1990, the federal Age Discrimination
         in Employment Act of 1967 (as amended), and the California Fair
         Employment and Housing Act (as amended).


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15.      SECTION 1542 WAIVER. You acknowledge reading and understanding Section
         1542 of the Civil Code of the State of California:

                  A GENERAL RELEASE DOES NOT EXTEND TO CLAIMS WHICH THE CREDITOR
                  DOES NOT KNOW OR SUSPECT TO EXIST IN HIS FAVOR AT THE TIME OF
                  EXECUTING THE RELEASE, WHICH IF KNOWN BY HIM MUST HAVE
                  MATERIALLY AFFECTED HIS SETTLEMENT WITH THE DEBTOR.

         You hereby expressly waive and relinquish all rights and benefits under
         that section and any law or legal principle of similar effect in any
         jurisdiction with respect to the release of unknown and unsuspected
         claims granted in this Agreement.

16.      ARBITRATION. To ensure rapid and economical resolution of any and all
         disputes that may arise in connection with the Agreement, the parties
         agree that any and all disputes, claims, causes of action, in law or
         equity, arising from or relating to this Agreement or its enforcement,
         performance, breach, or interpretation, with the sole exception of
         those disputes that may arise from your Employment Agreement , will be
         resolved by final and binding confidential arbitration held in San
         Diego, California and conducted by the American Arbitration Association
         ("AAA") under its then-existing Rules and Procedures. Nothing in this
         paragraph is intended to prevent either party from obtaining injunctive
         relief in court to prevent irreparable harm pending the conclusion of
         any such arbitration.

17.      ENTIRE AGREEMENT. This Agreement, including all exhibits, constitutes
         the complete, final and exclusive embodiment of the entire agreement
         between you and the Company with regard to the subject matter hereof.
         It supersedes any and all agreements entered into by and between you
         and the Company where such other agreement may conflict with this
         agreement. It is entered into without reliance on any promise or
         representation, written or oral, other than those expressly contained
         herein. It may not be modified except in a writing signed by you and a
         duly authorized officer of the Company. The parties have carefully read
         this Agreement, have been afforded the opportunity to be advised of its
         meaning and consequences by their respective attorneys, and signed the
         same of their own free will.

18.      MISCELLANEOUS. This Agreement shall bind the heirs, personal
         representatives, successors, assigns, executors and administrators of
         each party, and inure to the benefit of each party, its heirs,
         successors and assigns. This Agreement shall be deemed to have been
         entered into and shall be construed and enforced in accordance with the
         laws of the State of California as applied to contracts made and to be
         performed entirely within California. If an arbitrator or court of
         competent jurisdiction determines that any term or provision of this
         Agreement is invalid or unenforceable, in whole or in part, then the
         remaining terms and provisions hereof shall be unimpaired, the invalid
         or unenforceable term or provision shall be modified or replaced so as
         to render it valid and enforceable in a manner which represents the
         parties' intention with respect to the invalid or unenforceable term or
         provision insofar as possible. This Agreement may be executed in two
         counterparts, each of which shall be deemed an original, all of which
         together shall constitute one and the same instrument.


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Please confirm your agreement to the foregoing terms and conditions of this
Agreement by signing and returning a copy of this letter to Susan Ross on or
before July 29, 2002.

We regret having to take this action and wish you the best in your future
endeavors.

Sincerely,

CORVAS INTERNATIONAL, INC.

/s/ RANDALL E. WOODS
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Randall E. Woods
President and Chief Executive Officer




I HAVE READ AND REVIEWED THE FOREGOING, AND DO HEREBY AGREE TO ACCEPT THE TERMS
AND CONDITIONS OF THIS AGREEMENT AS STATED ABOVE.



/s/ KEVIN S. HELMBACHER                     Date: August 5, 2002
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Kevin Helmbacher, Esq.


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