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December 16, 1998

Gerard Wills
903 El Dorado Drive
Escondido, CA 92025

Dear Gerard:

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 Chief Financial Officer reporting to Michael
Grey, President & CEO. Your employment will begin on January 11, 1999 with an
exempt monthly salary of $16,666.67.(1)

In addition to your base compensation, you will be eligible to participate in 
an attractive bonus award program.  During your first year of employment, up 
to a maximum of 50% of your annual salary will be awarded to you should you 
successfully accomplish the criteria to be determined upon the commencement 
of your position.

You will be eligible to participate in the Company's health-care benefit 
plans on the first of the month following your hire date 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 15 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 150,000 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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Gerard Wills
December 16, 1998
page 2


You acknowledge that as a condition of employment you will be required to 
execute a Confidentiality Agreement and any and all other documents 
reasonably required by the Company to protect its proprietary trade secrets 
from disclosure and to prevent the unauthorized use by the Company of any 
proprietary trade secrets of other parties or entities.  These documents are 
attached to this letter as Exhibit A and are incorporated into this letter by 
reference.

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 (see Exhibit B).

Gerard, 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/ Michael G. Grey
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Michael Grey,
President & Chief Executive Officer

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


/s/ Gerard A. Wills                  12/22/98
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Gerard Wills                         Date