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 *
BAKER BROS. ADVISORS LP
  2. Issuer Name and Ticker or Trading Symbol
ACADIA PHARMACEUTICALS INC [ACAD]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director __X__ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
860 WASHINGTON STREET, 3RD FLOOR
3. Date of Earliest Transaction (Month/Day/Year)
11/30/2018
(Street)

NEW YORK, NY 10014
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
Common Stock 11/30/2018   P   585,882 A $ 17 3,736,902 I See Footnotes (1) (2) (8) (9)
Common Stock 11/30/2018   P   11,178,823 A $ 17 35,976,940 I See Footnotes (1) (3) (8) (9)
Common Stock 11/30/2018   J   489,977 D $ 0 0 I See Footnotes (4) (5) (8) (9)
Common Stock 11/30/2018   J   71,647 A $ 0 71,647 (6) D  
Common Stock 11/30/2018   J   71,647 A $ 0 71,647 (7) D  

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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) $ 0.01 11/30/2018   J     10,731 06/17/2013 12/17/2019 Common Stock 10,731 (11) 0 I See Footnotes (8) (9) (10) (12)
Common Stock Warrant (right to buy) $ 0.01 11/30/2018   J   1,569   06/17/2013 12/17/2019 Common Stock 1,569 (11) 1,569 (13) D  
Common Stock Warrant (right to buy) $ 0.01 11/30/2018   J   1,569   06/17/2013 12/17/2019 Common Stock 1,569 (11) 1,569 (14) D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
BAKER BROS. ADVISORS LP
860 WASHINGTON STREET
3RD FLOOR
NEW YORK, NY 10014
  X   X    
14159, L.P.
860 WASHINGTON STREET, 3RD FLOOR
NEW YORK, NY 10014
  X   X    
667, L.P.
860 WASHINGTON STREET, 3RD FLOOR
NEW YORK, NY 10014
  X   X    
Baker Bros. Advisors (GP) LLC
860 WASHINGTON STREET
3RD FLOOR
NEW YORK, NY 10014
  X   X    
Baker Brothers Life Sciences LP
860 WASHINGTON STREET
3RD FLOOR
NEW YORK, NY 10014
  X   X    
BAKER FELIX
860 WASHINGTON STREET
3RD FLOOR
NEW YORK, NY 10014
  X   X    
BAKER JULIAN
860 WASHINGTON STREET, 3RD FLOOR
NEW YORK, NY 10014
  X   X    

Signatures

 By: Baker Bros. Advisors LP, Name: Scott L. Lessing, Title: President /s/ Scott L. Lessing   12/04/2018
**Signature of Reporting Person Date

 Baker Bros. Advisors LP, Mgmt. Co. and Inv. Adviser to 14159, L.P., pursuant to authority granted by 14159 Capital, L.P., GP to 14159, L.P. Name: Scott L. Lessing Title: President /s/ Scott L. Lessing   12/04/2018
**Signature of Reporting Person Date

 Baker Bros. Advisors LP, Mgmt. Co. and Inv. Adviser to 667, L.P., pursuant to authority granted by Baker Biotech Capital, L.P., GP to 667, L.P. Name: Scott L. Lessing,Title: President /s/ Scott L. Lessing   12/04/2018
**Signature of Reporting Person Date

 By: Baker Bros. Advisors (GP) LLC, Name: Scott L. Lessing, Title: President /s/ Scott L. Lessing   12/04/2018
**Signature of Reporting Person Date

 Baker Bros. Advisors LP, Mgmt. Co. and Inv. Adviser to BAKER BROTHERS LIFE SCIENCES, L.P., pursuant to authority granted by Baker Brothers Life Sciences Capital, L.P., GP to Baker Brothers Life Sciences, L.P., Name: Scott L. Lessing, Title: President /s/   12/04/2018
**Signature of Reporting Person Date

 /s/ Felix J. Baker   12/04/2018
**Signature of Reporting Person Date

 /s/ Julian C. Baker   12/04/2018
**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) 667, L.P. ("667") and Baker Brothers Life Sciences, L.P. ("Life Sciences") purchased 585,882 and 11,178,823 shares of Common Stock, respectively, for $17.00 per share in an underwritten public offering (the "Offering") that closed on November 30, 2018.
(2) After giving effect to the transactions reported herein and as a result of their ownership interest in Baker Biotech Capital (GP), LLC, Julian C. Baker and Felix J. Baker each may be deemed to have an indirect pecuniary interest in the Issuer's shares of Common Stock reported in column 5 of Table I directly held by 667, a limited partnership of which the sole general partner is Baker Biotech Capital, L.P., a limited partnership of which the sole general partner is Baker Biotech Capital (GP), LLC, due to Baker Biotech Capital, L.P.'s right to receive an allocation of a portion of the profits from 667.
(3) After giving effect to the transactions reported herein and as a result of their ownership interest in Baker Brothers Life Sciences Capital (GP), LLC, Julian C. Baker and Felix J. Baker each may be deemed to have an indirect pecuniary interest in the Issuer's shares of Common Stock reported in column 5 of Table I directly held by Life Sciences, a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital, L.P., a limited partnership of which the sole general partner is Baker Brothers Life Sciences Capital (GP), LLC, due to Baker Brothers Life Sciences Capital, L.P.'s right to receive an allocation of a portion of the profits from Life Sciences.
(4) Represents 489,977 shares of Common Stock distributed by 14159, L.P. ("14159", and together with 667 and Life Sciences (the "Funds") as part of an in-kind pro rata distribution without consideration in accordance with pecuniary interest to Julian C. Baker, Felix J. Baker and other investors in 14159, L.P.
(5) After giving effect to the transactions reported herein and as a result of their ownership interest in 14159 Capital (GP), LLC, Julian C. Baker and Felix J. Baker may be deemed to have an indirect pecuniary interest in the Issuer's Common Stock reported in column 5 of Table I directly held by 14159, a limited partnership of which the sole general partner is 14159 Capital, L.P., a limited partnership of which the sole general partner is 14159 Capital (GP), LLC, due to 14159 Capital, L.P.'s right to receive an allocation of a portion of the profits from 14159.
(6) Reflects 71,647 shares of Common Stock held directly by Julian C. Baker received from the in-kind pro rata distribution without consideration reported above.
(7) Reflects 71,647 shares of Common Stock held directly by Felix J. Baker received from the in-kind pro rata distribution without consideration reported above.
(8) Baker Bros. Advisors LP (the "Adviser") serves as the Investment Adviser to the Funds. In connection with the services provided by the Adviser, the Adviser receives an asset-based management fee that does not confer any pecuniary interest in the securities held by the Funds. Baker Bros. Advisors (GP) LLC (the "Adviser GP") is the Adviser's sole general partner. Julian C. Baker and Felix J. Baker are Managing Members of the Adviser GP. The Adviser has complete and unlimited discretion and authority with respect to the investment and voting power of the securities held by the Funds. The general partners of the Funds have relinquished to the Adviser all discretion and authority with respect to the investment and voting power of the securities held by the Funds.
(9) Julian C. Baker, Felix J. Baker, the Adviser GP and the Adviser disclaim beneficial ownership of the securities held directly by the Funds except to the extent of their pecuniary interest therein, and this report shall not be deemed an admission that any of Julian C. Baker, Felix J. Baker, the Adviser GP or the Adviser is a beneficial owner of such securities for purposes of Section 16 or any other purpose.
(10) Represents 10,731 warrants to purchase Common Stock at an exercise price of $0.01 per share with an expiration date of December 17, 2019 distributed by 14159, L.P. as part of an in-kind pro rata distribution without consideration in accordance with pecuniary interest to Julian C. Baker, Felix J. Baker and other investors in 14159, L.P.
(11) Pursuant to Instruction 4(c)(iii), this response has been left blank.
(12) After giving effect to the transactions reported herein and as a result of their ownership interest in 14159 Capital (GP), LLC, Julian C. Baker and Felix J. Baker may be deemed to have an indirect pecuniary interest in the Issuer's securities reported in column 9 of Table II directly held by 14159, a limited partnership of which the sole general partner is 14159 Capital, L.P., a limited partnership of which the sole general partner is 14159 Capital (GP), LLC, due to 14159 Capital, L.P.'s right to receive an allocation of a portion of the profits from 14159.
(13) Reflects 1,569 warrants to purchase Common Stock at an exercise price of $0.01 per share with an expiration date of December 17, 2019 held directly by Julian C. Baker received from the in-kind pro rata distribution without consideration reported above.
(14) Reflects 1,569 warrants to purchase Common Stock at an exercise price of $0.01 per share with an expiration date of December 17, 2019 held directly by Felix J. Baker received from the in-kind pro rata distribution without consideration reported above.
 
Remarks:
Julian C. Baker, a Managing Member of Baker Bros. Advisors (GP) LLC and Dr. Stephen R. Biggar, a full-time employee of Baker Bros. Advisors LP are directors of ACADIA Pharmaceuticals Inc. (the "Issuer"). For purposes of Section 16 of the Securities Exchange Act of 1934, as amended, the reporting persons are deemed directors by deputization by virtue of their representation on the Board of Directors of the Issuer.

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