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April 17, 1998

Via Federal Express

Leonard Borrmann, Pharm D
27 Recodo
Irvine, CA 92620

Dear Leonard,

As discussed, I am pleased to offer you the position of Chief Executive Officer
of ACADIA Pharmaceuticals Inc. I firmly believe that with your joining and
leading our team, ACADIA Pharmaceuticals will have the potential to not only
quickly surpass such short term goals as completing additional significant
corporate partnerships and a successful public offering, but that we will be
able to flourish in facing the challenges to be met in the years ahead as we
build an extremely valuable, technology driven, integrated drug discovery
company. All of us associated with ACADIA Pharmaceuticals look forward to
working with you. The terms of our offer are as follows:

1.       Your title will be Chief Executive Officer and you will report to the
         Board of Directors of the Company. You agree to devote all of your
         business time, attention and energies to the business of the Company.

2.       You will become a member of the Board of Directors of the Company at
         the first Board Meeting to be held after your beginning employment with
         ACADIA, and for so long as you hold the position of Chief Executive
         Officer, will be nominated by the Board to the Stockholders for
         election as Director.

3.       Your initial annual salary will be $220,000, subject to adjustment as
         determined by the Board as of January 1 of each year.

4.       You will be eligible to receive an annual bonus with a target amount of
         20 to 30% of the base salary you receive in each calendar year payable
         within 90 days of the end of such Calendar year. The amount of the
         annual bonus will be determined by the Board of Directors based upon
         the accomplishment of significant goals determined by the Board and you
         at the beginning of each year.

5.       Naturally, what I consider to be the most important part of your
         compensation is your participation in the Company's 1997 Stock Option
         Plan. You will receive stock options to purchase 300,000 shares of
         Common Stock of the Company. The options will vest 25% of the shares
         after 12 months of employment with additional vesting of 1/48th of the
         shares after each additional month of employment through your 48th
         month of employment with the Company. The stock options will be subject
         to the aforementioned vesting schedule and other terms of the Plan. The
         exercise price at which these options will be issued will be equal to
         the fair market value of the common shares of the Company at the date
         of grant of the options, which will be the start date of your
         employment. In the event the company completes an Acquisition Event as
         defined in the

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         Company's 1997 Stock Option Plan, any unvested options you then hold
         will be immediately vested.

         In the event the Company completes an Initial Public Offering (IPO),
         you will receive options to purchase an additional 50,000 shares of
         common stock of the Company. These options will vest 1/48th per each
         additional month of employment with the Company through your 48th month
         of employment following the grant date of such options. The exercise
         price at which these options will be issued will be equal to the fair
         market value of the shares of Common Stock of the Company at the IPO.

         Enclosed is a copy of the ACADIA Pharmaceuticals 1997 Stock Option
         Plan. Note that there are currently approximately 7.4 million common
         equivalent shares outstanding, fully diluted for the shares reserved
         for the 1997 Stock Option Plan.

6.       The Company will also provide you a signing bonus of $50,000 payable
         immediately after your beginning employment with ACADIA Pharmaceuticals
         Inc. You agree to return such bonus to the Company if you voluntarily
         terminate your employment within six months of the start date of your
         employment.

7.       In the event the Company terminates your employment, other than for
         cause as defined below, you will receive severance in the form of the
         continuation of your salary for the one year period following the
         termination of your employment plus the benefits you were receiving at
         the time of your termination (subject to the terms of the Company's
         benefit plans). You will also be entitled to receive a bonus payment
         equal to the bonus, if any, you would have otherwise received had you
         been employed for such period. Such amount will be as determined by the
         Board, but in any event, will not be less than the bonus received from
         the Company for the year immediately preceding the year of termination.
         Such payment will be made within 90 days following termination.

         For purposes of the above "cause" for termination shall be deemed to
         exist upon (a) a good faith finding by the Company of material failure
         of the Employee to perform his assigned duties for the Company,
         dishonesty, gross negligence or other material misconduct, or (b) the
         conviction of the Employee of, or the entry of a pleading of guilty or
         nolo contendere by the Employee to, any crime involving moral turpitude
         or any felony.

8.       You will be provided all of the standard company benefits, including
         four weeks paid vacation, health insurance, group term life and
         accidental death and dismemberment insurance, group disability
         insurance, travel accident insurance, and the ability to participate in
         the Company's 401k plan which includes matching of employees'
         contributions to the plan up to 5% of compensation. Enclosed is
         information regarding the Company's various benefit programs. With
         respect to the Company's matching of contributions to the 401k plan up
         to 5% of compensation, note that it is the intention of the Company to
         provide the 5% payment to all employees interested in deferring 5% of
         their compensation even if their deferrals to the 401k plan are
         otherwise limited to less than 5% of total compensation due to various
         IRS rules. After you join the Company,

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         and with your input, we can conclude on an appropriate non-qualified
         or other arrangement in this regard.

9.       As a condition of your employment you will be required to agree to and
         sign the Company's standard Disclosure and Inventions Agreement, a copy
         of which is attached.

10.      The start date for your employment will be May 11, 1998 or other
         mutually agreeable date.

11.      Except as required by law, you and the Company agree that no public
         announcement of your prospective employment will be made until after
         you have formally accepted employment and that any related press
         release will be provided to you in advance for your review and
         approval.

Leonard, I am very confident that your joining the ACADIA team will prove
extremely beneficial to both you and the Company and its shareholders. If you
have any questions, please do not hesitate to call me at the office or at home.

Sincerely yours,

/s/ Mark R. Brann, Ph.D.

Mark R. Brann, Ph.D.

Founder, Chief Executive and Scientific Officer and President


I accept your offer to become Chief Executive Officer of ACADIA Pharmaceuticals
Inc. in accordance with the terms included above:


Signature:  /s/ Leonard Borrmann                   Date:       4/20/95
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                Leonard Borrmann, Pharm D

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