Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
OXFORD BIOSCIENCE PARTNERS IV LP
  2. Issuer Name and Ticker or Trading Symbol
ACADIA PHARMACEUTICALS INC [ACAD]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
222 BERKELEY ST.
3. Date of Earliest Transaction (Month/Day/Year)
07/29/2005
(Street)

BOSTON, MA 02116
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
___ Form filed by One Reporting Person
_X_ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Common Stock Warrant (right to buy) $ 8.148 07/29/2005   P   89,900   10/17/2005 04/19/2010 Common Stock 89,900 $ 3.09 236,500 D (1)  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
OXFORD BIOSCIENCE PARTNERS IV LP
222 BERKELEY ST.
BOSTON, MA 02116
    X    
MRNA FUND II LP
222 BERKELEY ST.
BOSTON, MA 02116
    X    
OBP MANAGEMENT IV LP
222 BERKELEY ST.
BOSTON, MA 02116
    X    
BARNES JEFFREY T
222 BERKELEY ST.
BOSTON, MA 02116
    X    
CARTHY MARK
222 BERKELEY ST.
BOSTON, MA 02116
    X    
FLEMING JONATHAN
222 BERKELEY ST.
BOSTON, MA 02116
    X    
LYTTON MICHAEL
222 BERKELEY ST.
BOSTON, MA 02116
    X    
WALTON ALAN G
222 BERKELEY ST.
BOSTON, MA 02116
  X   X    

Signatures

 /s/ Raymond Charest, as attorney-in-fact for Jonathan J. Fleming, as general partner of the general partner of Oxford Bioscience Partners IV L.P.   08/02/2005
**Signature of Reporting Person Date

 /s/ Alexia Pearsall, as attorney-in-fact for Jonathan J. Fleming, as general partner of the general partner of mRNA Fund II L.P.   08/02/2005
**Signature of Reporting Person Date

 /s/ Raymond Charest, as attorney-in-fact for Jonathan J. Fleming, as general partner of OBP Management IV L.P.   08/02/2005
**Signature of Reporting Person Date

 /s/ Raymond Charest, as attorney-in-fact for Jeffrey T. Barnes   08/02/2005
**Signature of Reporting Person Date

 /s/ Raymond Charest, as attorney-in-fact for Mark P. Carthy   08/02/2005
**Signature of Reporting Person Date

 /s/ Raymond Charest, as attorney-in-fact for Jonathan J. Fleming   08/02/2005
**Signature of Reporting Person Date

 /s/ Michael E. Lytton   08/02/2005
**Signature of Reporting Person Date

 /s/ Raymond Charest, as attorney-in-fact for Alan G. Walton   08/02/2005
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Securities held of record by Oxford Bioscience Partners IV L.P. ("Oxford IV"). By virtue of their relationship as affiliated limited partnerships, whose sole general partner shares individual general partners, Oxford IV and mRNA Fund II L.P. ("mRNA") may be deemed to share voting power and the power to direct the disposition of the shares which each partnership owns of record. OBP Management IV L.P. ("OBP IV") (as the general partner of Oxford IV), may also be deemed to own beneficially the shares held of record by Oxford IV. Each of Messrs. Barnes, Carthy, Fleming, Lytton, and Walton (who is a Director of the Issuer), the individual general partners of OBP IV, may be deemed to own beneficially the shares held by Oxford IV. The reporting persons disclaim beneficial ownership of the securities except to the extent of their pecuniary interest therein.

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