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January 11, 1999



John Wehrli
1879 Springer Road #B
Mountain View, CA 94040

Dear John:

We are pleased to extend you an offer of employment with Trega Biosciences, 
Inc (the "Company").  This letter shall serve to clarify the terms and 
conditions of the job we are offering you. 

We are offering you a position as Senior Director, Legal Affairs reporting to 
Michael Grey, President & Chief Executive Officer. Your employment will begin 
Monday, February 1, 1999 with an exempt monthly salary of $12,500.(1) Trega 
will also pay reasonable moving expenses incurred with the relocation of your 
household goods to San Diego to include: 1) shipment of household goods and 
one vehicle, 2) temporary housing in San Diego, CA for 30-60 days, 3) one-way 
airfare from San Francisco to San Diego, CA. Trega will also extend a loan to 
you in the amount of $120,000 which will be secured by vested Trega stock. 
The loan will be offered at the lowest interest rate available based on the 
signing date of this offer letter and will be due 24 months from signing. 
Should your employment relationship with Trega end, you will be required to 
repay the Company for the remaining balance plus accrued interest within six 
(6) months. Furthermore, Trega will pay directly to Cooley Godward, the 
reimbursement costs for your legal education, which we approximate to be 
$13,000.

In addition to your base compensation, you will be eligible to participate in 
an attractive bonus award program.  Although the details of the Company 
program have not been finalized be assured that you will receive a bonus 
appropriate to your position and based on the company's financial 
performance. 

You will be eligible to participate in the Company's health-care benefit 
plans on your date of hire and in the Company's 401 (k) Retirement Plan 
during the first enrollment period following 90 days after your hire date.  
You will begin accruing vacation at a rate of 10 days per year, with an 
additional day of vacation for every year of service, which you will be 
eligible to take after six (6) months of employment with the Company. Subject 
to the approval of the Compensation Committee, you will be granted an option 
to acquire 60,000 shares of stock. The option is subject to the terms of the 
Option Agreement and the 1996 Stock Incentive Plan. 

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(1) Please be advised that this offer is contingent on your completing an I-9
form and submitting support information regarding your right to work in the
United States within three days of hire.


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John Wehrli
January 11, 1999
page 2



You will not be required to sign an additional Confidentiality Agreement, as 
the existing Agreement still applies.

You acknowledge and agree that in accordance with California law, your
employment with the Company is "at will" and that you understand that the
Company or you may terminate your employment at any time, for any reason
whatsoever, with or without cause and with or without notice. The Company also
reserves the right to make personnel decisions regarding your employment,
including but not limited to discussions regarding any promotion, salary
adjustment, transfer or disciplinary action, up to and including termination
consistent with the needs of the business.

You further and the Company further agree that all disputes, claims or causes of
action arising out of or relating to your employment or its termination, shall
be submitted to binding arbitration before a neutral arbitrator, except where
the law specifically forbids the use of arbitration as a final and bind remedy
(Exhibit B received with NaviCyte offer).

John, we look forward to your joining our organization.  In order to confirm
your agreement with and acceptance of these terms, please sign one copy of this
letter and return it to me.  The other copy is for your records.  If there is
any matter in this letter which you wish to discuss further, please do not
hesitate to speak to me.

Sincerely,


/s/ Susan M. Hanan
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Susan Hanan,
Vice President Organizational & Strategic Development


                                   ACKNOWLEDGMENT

I agree to the terms and conditions of employment set forth in this letter.

/s/ John E. Wehrli                             1/12/99
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John Wehrli                             Date