13D Filing: Baker Bros. Advisors and Acadia Pharmaceuticals Inc (NASDAQ:ACAD)

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Page 2 of 10 – SEC Filing

CUSIP No.   004225108   Page   2   of   10   Pages
1.

NAMES OF REPORTING PERSONS

Baker Bros. Advisors LP

2.

CHECK
THE APPROPRIATE BOX IF A MEMBER OF A GROUP*

(a) ¨

(b) ¨

3.

SEC USE ONLY

4.

SOURCE OF FUNDS*

OO

5.

CHECK
BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEM 2(d) or 2(e)
o

6.

CITIZENSHIP OR PLACE OF ORGANIZATION

Delaware

NUMBER
OF SHARES
BENEFICIALLY
OWNED
BY EACH
REPORTING
PERSON WITH

7.

SOLE VOTING POWER:

28,570,614 (1)

8.

SHARED VOTING POWER:

0

9.

SOLE DISPOSITIVE POWER:

28,570,614 (1)

10.

SHARED DISPOSITIVE POWER:

0

11.

AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:

28,570,614 (1)

12.

CHECK
BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES*

¨

13.

PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

22.8% (1)(2)

14.

TYPE OF REPORTING PERSON*

IA, PN

(1)

Includes 46,250 shares of the common stock of ACADIA Pharmaceuticals Inc. (the “Issuer”) underlying
options directly held by Julian C. Baker, a Managing Member of Baker Bros. Advisors (GP) LLC (“the Adviser GP”) and
85,250 shares of the common stock of the Issuer underlying options directly held by Dr. Stephen R. Biggar, a full-time employee
of Baker Bros. Advisors LP (the “Adviser”).

(2) Based on 125,006,723 shares of the Issuer’s common
stock outstanding as of July 31, 2018, as reported in the Issuer’s Form 10-Q filed with the Securities Exchange Commission
(“SEC”) on August 8, 2018.

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