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                                                                   EXHIBIT 10.41


October 27, 1998



Stephen F. Keane
2780 Angell Avenue
San Diego, CA   92122

Dear Steve:

SIBIA Neurosciences, Inc., is pleased to offer you the position of Vice
President, Corporate Development reporting to me, the President and CEO. Your
main responsibility will be to establish value-building relationships with
pharmaceutical and biotechnology companies as well as with academic
institutions, especially to initiate, structure and negotiate business
development agreements that maximize the company's assets and support its
strategic mission. Duties will include overseeing Intellectual Property,
Investor Relations and developing the rationale for acquisition of
products/businesses that significantly enhance the realization of the company's
vision. Your starting salary will be $12,500.00 per month and you will be
eligible for SIBIA benefits which include medical, dental, long term disability,
401(k), life insurance, vacation, and sick leave. These benefits may be amended
from time to time.

After your acceptance of this offer, and commencement of employment at SIBIA, I
will recommend to the Compensation and Stock Option Committee of SIBIA's Board
of Directors that you be granted an option to purchase 60,000 shares of SIBIA
Common Stock under our 1996 Equity Incentive Plan. You will also be eligible for
additional stock option grants on a yearly basis under the company's long-term
incentive policy.

Additionally, SIBIA has adopted an incentive plan which consists of a bonus
pool, established at the discretion of the Board of Directors, reviewed each
year, and based on overall company performance. As a Vice President, your bonus
opportunity will be established at 15% of salary with the actual amount
dependent upon an assessment of your performance and your contribution to the
team effort. For the 1998/99 bonus year, you will be guaranteed a minimum of
$20,000 of which $5,000 will be paid as a sign-on bonus with the remaining
$15,000 paid after your performance review on April 15, 1999.

A Patent/Confidentiality Agreement will need to be executed by you as part of
your employment with SIBIA. A copy of this agreement is enclosed for your
review.



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Stephen F. Keane
Page Two
October 27, 1998


As an officer of the company you will be entitled to certain benefits in the
Change of Control Plan attached.

Both SIBIA and you have the right to terminate your employment at any time for
any reason, with or without cause, and with or without notice. Similarly,
promotions, transfers, demotions, suspensions and employee discipline may be
effected or administered at the will of SIBIA at any time for any reason, with
or without cause, and with or without notice.

This letter agreement contains the entire agreement between the parties. It
supersedes any and all other agreements, either oral or in writing, between you
and SIBIA with respect to your employment by SIBIA. SIBIA and you both
acknowledge that no representations, inducements, promises or agreements, oral
or otherwise, have been made by any party, or anyone acting on behalf of any
party, which are not embodied herein, and acknowledge that no other agreement,
statement or promise not contained in this letter agreement shall be valid or
binding. This letter agreement may not be modified by oral agreement, or course
of conduct, but only by an agreement in writing signed by the President of SIBIA
and you.

We would like to have your decision regarding this offer by October 30, 1998 and
would like to anticipate a start date of no later than November 15, 1998. To
formally accept this offer on the above terms, please sign one copy of this
letter and return it to me.

The members of the SIBIA staff and I personally hope that you will decide to
join us and I very much look forward to working with you.

Yours very sincerely,

/s/ William T. Comer
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William T. Comer, Ph.D.
President and CEO

Accepted and agreed to this 27th day of October, 1998.


/s/ Stephen F. Keane
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Stephen F. Keane                            Social Security Number