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                    SEPARATION AGREEMENT AND GENERAL RELEASE


This Separation Agreement and General Release ("Agreement") is made and entered
into by and between Dr. Leonard Borrmann ("Borrmann") and ACADIA
Pharmaceuticals, Inc. (the "Company"), as of September 20, 2000 (the "Effective
Date"). Borrmann and the Company hereby agree as follows:

1. SEPARATION DATE. Effective on the last date signed below, Borrmann has
tendered and the Company has accepted Borrmann's resignation as an employee and
a director and any and all other positions Borrmann may have held with the
Company and/or its affiliates (the "Separation Date").

2. ACCRUED SALARY AND VACATION. The Company agrees that immediately upon
execution of this Agreement it will pay Borrmann all accrued salary, and all
accrued and unused vacation benefits earned through the Separation Date, if any,
subject to standard payroll deductions, withholding taxes and other obligations.

3. EXPENSE REIMBURSEMENT. Within thirty (30) business days of Borrmann's
execution of this Agreement, Borrmann agrees that Borrmann will submit
Borrmann's final documented expense reimbursement statement reflecting all
business expenses Borrmann incurred prior to and including the Separation Date,
if any, for which Borrmann seeks reimbursement. The Company shall reimburse
Borrmann's expenses pursuant to Company policy and regular business practice.

4. SALARY AND BENEFIT CONTINUATION. In exchange for Borrmann's resignation
and the releases and waivers given pursuant to this Agreement, the Company
agrees to provide Borrmann with the benefits specified in paragraph 7 of
Borrmann's employment letter agreement dated April 17, 1998, a copy of which
is annexed to this Agreement as Exhibit A, consisting of continuation of
Borrmann's base salary, less standard deductions and withholdings, paid twice
monthly on the fifteenth (15th) day of each month and on the final day of
each month for one year following the Separation Date (the "Salary
Continuation Period") and continuation of standard Company benefits of group
health insurance coverage for Borrmann and Borrmann's family, travel accident
insurance coverage during the Salary Continuation Period, payment of four
weeks of vacation which is the sum of $18,569.00, less standard deductions
and withholdings, within fifteen (15) days following the Separation Date, and
the continuation of Borrmann's and Borrmann's family's right to participate
in the Company's group dental plan and the Company's Section 125 Flexible
Spending Plan (provided that Borrmann agrees to contribute the same amount he
contributed to the dental plan and 125 Flexible Spending Plans during his
employment), and the Company's 401k plan during the Salary Continuation
Period, subject to the terms of the applicable plans and COBRA where
applicable. In addition, pursuant to paragraph 7 of Borrmann's employment
letter, the Company will pay Borrmann a bonus payment equal to sixty thousand
three hundred fifty-three dollars ($60,353.00), less standard deductions and
withholdings, within ninety (90) days following the Separation Date. The
Company also agrees to continue Borrmann's base salary, less standard
deductions and withholdings, and continue Borrmann's standard Company
benefits of group health insurance coverage for Borrmann and Borrmann's
family and Borrmann's travel accident insurance

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coverage, and provide Borrmannn and Borrmann's family the right to
participate in the Company's group dental plan and the Company's Section 125
Flexible Spending Plan (provided that Borrmann agrees to contribute the same
amount he contributed to the dental plan and 125 Flexible Spending Plans
during his employment), pursuant to the terms of the applicable plans and
COBRA where applicable, beyond the last day of the Salary Continuation Period
of up to a maximum of six months, determined on a month to month basis,
provided that Borrmann is not gainfully employed during such six month period
despite his reasonable good faith efforts to obtain gainful employment. Any
such payments beyond the last day of the Salary Continuation Period shall be
made only once a month. The Company has the right to request proof of
Borrmann's efforts to obtain gainful employment.

5. STOCK OPTIONS. In exchange for the promises and covenants set forth herein,
the Company agrees to accelerate the vesting of the stock options held by
Borrmann as to 31,250 shares of the Company's common stock such that, as of the
Separation Date, the number of shares vested under such stock options shall
equal 200,000 shares. The Company also agrees to extend the exercise period of
Bormann's stock options to September 20, 2007. Borrmann understands that to the
extent he does not exercise his vested stock options within three (3) months of
the Separation Date, any of the stock options originally granted as incentive
stock options will no longer be treated as such, but instead will be treated for
tax purposes as if they were non-qualified stock options. Borrmann acknowledges
that the Company has advised him to seek guidance from a tax advisor in the
event he has questions regarding the tax treatment of his stock options and
agrees to hold the Company harmless for any tax consequences he may incur as a
result of the extension of the exercise period of his options.

6. OTHER COMPENSATION AND BENEFITS. Except as expressly provided herein,
Borrmann acknowledges and agrees that Borrmann is not entitled to and will not
receive any additional compensation, severance, stock options, stock or benefits
from the Company. Borrmann agrees and understands that all vesting under any
stock compensation award (e.g., incentive stock option, nonqualified stock
option, stock purchase agreement, or restricted stock bonus agreement) from the
Company shall cease upon the Separation Date.

7. NON-COMPETE AND NON-SOLICITATION.

         (a) NON-COMPETE: In exchange for the promises and covenants herein,
Borrmann agrees that during the Salary Continuation Period.

                  (i) Borrmann will not act as an owner, employee, officer,
director, agent or consultant, in the geographic area of the United States, with
a company whose primary business is the discovery of drugs for the treatment of
neuro-psychiatric disease, provided, however, that the ownership of two percent
(2%) or less of the stock of a company whose shares are listed on a national
securities exchange or are quoted on the National Association of Securities
Dealers Automated Quotation System shall not be deemed ownership or having an
interest which is prohibited hereunder;

                  (ii) Borrmann will not solicit any business from companies
with whom the Company has collaborative agreements as of the Separation Date,
for products or services competitive with those of the Company, if such
solicitation would negatively impact the business


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of the Company with such companies. Borrmann will not request, induce or
advise customers of the Company to withdraw, curtail or cancel their business
with the Company. For the purposes of this Article 7(a)(ii), "customer" shall
mean any company or entity with whom the Company has a material agreement and
from which the Company receives substantial revenues as of the Separation
Date; and

         (b) NONSOLICITATION. Borrmann agrees that for two (2) years following
the Separation Date, Borrmann will not, either directly or through others,
solicit or attempt to solicit any employee, consultant, or independent
contractor of the Company to terminate his or her relationship with the Company
in order to become an employee, consultant or independent contractor to or for
any other person or entity.

8. TERMINATION OF COMPANY'S OBLIGATIONS. Notwithstanding any provisions in this
Agreement to the contrary, the Company's obligations, and Borrmann's rights
pursuant to Section 4 herein, regarding the payment of salary continuation, and
Section 5 herein, regarding the extension of the exercise period for the stock
options, shall cease and be rendered a nullity immediately should Borrmann fail
to comply with any of the provisions of Sections 7 and 11 herein.

9. NO FURTHER EMPLOYMENT WITH THE COMPANY. Borrmann understands and agrees that,
as a condition of this Agreement, Borrmann shall not be entitled to any
employment with the Company, its parents or subsidiaries, and Borrmann hereby
waives any right, or alleged right, of employment or re-employment with the
Company and any of its parents, affiliates, or subsidiaries. Borrmann further
agrees that Borrmann will only be eligible to apply for employment with the
Company, its parents or subsidiaries, if Borrmann obtains prior written consent
from the Company, which consent may be withheld for any reason or no reason. In
order to carry out the intent of this Section and Section 1 of this Agreement,
Bormmann shall execture an Action by Written Consent of Sole Incorporator of
ACADIA PharmacoGenomics Inc., a copy of which is attached hereto as Exhibit B,
naming the directors of such subsidiary of the Company.

10. COMPANY PROPERTY. Upon the Separation Date, Borrmann agrees to return to the
Company all Company documents (and all copies thereof) and other Company
property in Borrmann's possession or Borrmann's control, including, but not
limited to, Company files, business plans, notes, samples, sales notebooks,
drawings, specifications, calculations, sequences, data, computer-recorded
information, tangible property, including, but not limited to, cellular phones,
credit cards, entry cards, keys and any other materials of any nature pertaining
to Borrmann's work with the Company, and any documents or data of any
description (or any reproduction of any documents or data) containing or
pertaining to any proprietary or confidential material of the Company.
Notwithstanding the foregoing, the Company agrees that in exchange for the
promises and covenants herein, the Company will provide and Borrmann may keep
the laptop computer, keyboard, docking station, and monitor and the personal
organizer and their related accessories that Borrmann used during his employment
with the Company and the Company will transfer ownership of such items to
Borrmann.

11. PROPRIETARY INFORMATION OBLIGATIONS. Borrmann acknowledges Borrmann's
continuing obligations under Borrmann's Disclosure and Inventions Agreement, a
copy of which


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is attached hereto as Exhibit C. Pursuant to such agreement Borrmann
understands that Borrmann must not use or disclose any confidential or
proprietary information of the Company, among other things.

12. NON-DISPARAGEMENT. Borrmann 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 provisions of this Agreement shall be
held in strictest confidence by Borrmann and the Company and shall not be
publicized or disclosed in any manner whatsoever; provided, however, that: (a)
Borrmann may disclose this Agreement, in confidence, to Borrmann's 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. Notwithstanding
the foregoing, in the event the Company issues a public disclosure regarding
Borrmann's resignation, the Company shall provide Borrmann with a copy of such
proposed disclosure by e-mail and Borrmann shall have the opportunity to review
and approve of the disclosure prior to its release, such approval not to be
unreasonably withheld. Borrmann agrees that his failure to respond to the
Company's delivery of the proposal and request for approval within twenty-four
(24) hours shall constitute his approval of the proposal.

14. RELEASE OF CLAIMS. In exchange for the promises and covenants set forth
herein, Borrmann hereby releases, acquits, and forever discharges the Company,
its parents and subsidiaries, and their officers, directors, agents, servants,
employees, attorneys, shareholders, partners, successors, assigns, affiliates,
customers, and clients of and from any and all claims liabilities, demands,
causes of action, costs, expenses, attorneys' fees, damages, indemnities and
obligations of every kind and nature, in law, equity, or otherwise, known and
unknown, suspected and unsuspected, disclosed and undisclosed, arising out of or
in any way related to agreements, acts or conduct at any time prior to the
Separation Date, including, but not limited to: all such claims and demands
directly or indirectly arising out of or in any way connected with the Company's
employment of Borrmann, the termination of that employment, and the Company's
performance of its obligations as Borrmann's former employer; claims or demands
related to salary, bonuses, commissions, stock, stock options, or any other
ownership interests in the Company, vacation pay, fringe benefits, expense
reimbursements, severance pay, or any form of compensation; claims pursuant to
any federal, state or local law or cause of action including, but not limited
to, the California Labor Code, the California Fair Employment and Housing Act,
the federal Civil Rights Act of 1964, as amended; the federal Americans With
Disabilities Act; tort law; contract law; wrongful discharge; discrimination;
harassment; fraud; defamation; emotional distress; and breach of the implied
covenant of good faith and fair dealing.

15. SECTION 1542 WAIVER. In giving this release, which includes claims which may
be unknown to Borrmann at present, Borrmann hereby acknowledges that Borrmann
has read and understand Section 1542 of the Civil Code of the State of
California which reads as follows:


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         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.

Borrmann hereby expressly waives and relinquishes all rights and benefits under
this section and any law or legal principle of similar effect in any
jurisdiction with respect to claims released hereby.

16. NO ADMISSIONS. The parties hereto hereby acknowledge that this is a
compromise settlement of various matters, and that the promised payments in
consideration of this Agreement shall not be construed to be an admission of any
liability or obligation by either party to the other party or to any other
person whomsoever.

17. ENTIRE AGREEMENT. This Agreement, including Exhibits A, B and C, constitutes
the complete, final and exclusive embodiment of the entire Agreement between
Borrmann and the Company with regard to the subject matter hereof. 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 Borrmann and a duly authorized officer of the Company. Each
party has carefully read this Agreement, has been afforded the opportunity to be
advised of its meaning and consequences by his or its respective attorneys, and
signed the same of his or its free will.

18. SUCCESSORS AND ASSIGNS. 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 agents, directors, officers,
employees, servants, heirs, successors and assigns.

19. APPLICABLE LAW. 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.

20. INJUNCTIVE RELIEF. Borrmann and the Company are each obligated under this
Agreement to render services and comply with covenants of a special, unique,
unusual and extraordinary character, thereby giving this Agreement peculiar
value, so that the loss of such service or violation by either party of this
Agreement could not reasonably or adequately be compensated in damages in an
action at law. Therefore, in addition to any other remedies or sanctions
provided by law, whether criminal or civil, and without limiting the right of
either party and their respective successors or assigns to pursue all other
legal and equitable rights available to them, Borrmann and the Company shall
each have the right to compel specific performance hereof by the other party or
to obtain temporary and permanent injunctive relief against violations hereof by
the other party, including, but not limited to violations of Sections 11, 12 and
13 herein and the Disclosure and Inventions Agreement, and, in furtherance
thereof, to apply to any court with jurisdiction over the parties to enforce the
provisions hereof.

21. SEVERABILITY. If a 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. Such court
will have the authority to modify or replace the invalid or unenforceable term
or


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provision with a valid and enforceable term or provision that most accurately
represents the parties' intention with respect to the invalid or unenforceable
term or provision.

22. INDEMNIFICATION. Each party will indemnify and save harmless each other
party hereto from any loss incurred directly or indirectly by reason of the
falsity or inaccuracy of any representation made herein.

23. AUTHORIZATION. Each party warrants and represents that there are no liens or
claims of lien or assignments in law or equity or otherwise of or against any of
the claims or causes of action released herein and, further, that Borrmann is
fully entitled and duly authorized to give the Company complete and final
general release and discharge. The Company represents that it is fully entitled
and duly authorized to comply with the promises and covenants stated herein.

24. COUNTERPARTS. 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.

25. SECTION HEADINGS. The section and paragraph headings contained in this
Agreement are for reference purposes only and shall not affect in any way the
meaning or interpretation of this Agreement.

LEONARD BORRMANN,
an individual.

/s/ Leonard Borrmann
--------------------------------
Leonard Borrmann

Dated: September 20, 2000
      --------------------------

ACADIA PHARMACEUTICALS, INC.

By: /s/ Thomas H. Aasen
   -----------------------------

Dated: September 20, 2000
      --------------------------


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