<SUBMISSION>
<ACCESSION-NUMBER>0001193125-09-062726
<TYPE>8-K
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20090324
<ITEMS>1.01
<FILING-DATE>20090325
<DATE-OF-FILING-DATE-CHANGE>20090325
<FILER>
<COMPANY-DATA>
<CONFORMED-NAME>ACADIA PHARMACEUTICALS INC
<CIK>0001070494
<ASSIGNED-SIC>2834
<IRS-NUMBER>061376651
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<FILING-VALUES>
<FORM-TYPE>8-K
<ACT>34
<FILE-NUMBER>000-50768
<FILM-NUMBER>09703190
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>3911 SORRENTO VALLEY BLVD
<CITY>SAN DIEGO
<STATE>CA
<ZIP>92121
<PHONE>858-558-2871
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>3911 SORRENTO VALLEY BLVD
<CITY>SAN DIEGO
<STATE>CA
<ZIP>92121
</MAIL-ADDRESS>
</FILER>
<DOCUMENT>
<TYPE>8-K
<SEQUENCE>1
<FILENAME>d8k.htm
<DESCRIPTION>FORM 8-K
<TEXT>
<HTML><HEAD>
<TITLE>Form 8-K</TITLE>
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 <P STYLE="line-height:0px;margin-top:0px;margin-bottom:0px;border-bottom:0.5pt solid #000000">&nbsp;</P> <P
STYLE="line-height:3px;margin-top:0px;margin-bottom:2px;border-bottom:0.5pt solid #000000">&nbsp;</P> <P STYLE="margin-top:24px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="4"><B>UNITED STATES </B></FONT></P> <P
STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="4"><B>SECURITIES AND EXCHANGE COMMISSION </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman"
SIZE="3"><B>WASHINGTON, D.C. 20549 </B></FONT></P> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P><center> <P STYLE="line-height:6px;margin-top:0px;margin-bottom:2px;border-bottom:1pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:6px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="5"><B>FORM 8-K </B></FONT></P> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P><center> <P
STYLE="line-height:6px;margin-top:0px;margin-bottom:2px;border-bottom:1pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:6px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="3"><B>CURRENT REPORT </B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="3"><B>PURSUANT TO SECTION 13 OR 15(d) OF THE </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman"
SIZE="3"><B>SECURITIES EXCHANGE ACT OF 1934 </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">Date of report (Date of earliest event reported): March&nbsp;25, 2009 (March 24, 2009)
</FONT></P> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P><center> <P STYLE="line-height:6px;margin-top:0px;margin-bottom:2px;border-bottom:1pt solid #000000;width:21%">&nbsp;</P></center> <P
STYLE="margin-top:6px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="6"><B>ACADIA PHARMACEUTICALS INC. </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>(Exact
Name of Registrant as Specified in Charter) </B></FONT></P> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P><center> <P
STYLE="line-height:6px;margin-top:0px;margin-bottom:2px;border-bottom:1pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TD VALIGN="top" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>DELAWARE</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>000-50768</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>06-1376651</B></FONT></TD></TR>
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<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>(State or Other Jurisdiction</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px" ALIGN="center"><FONT
FACE="Times New Roman" SIZE="1"><B>of Incorporation)</B></FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>(Commission</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px" ALIGN="center"><FONT FACE="Times New Roman"
SIZE="1"><B>File Number)</B></FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>(I.R.S. Employer</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px" ALIGN="center"><FONT
FACE="Times New Roman" SIZE="1"><B>Identification No.)</B></FONT></P></TD></TR>
</TABLE> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>3911 SORRENTO VALLEY BOULEVARD</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px" ALIGN="center"><FONT
FACE="Times New Roman" SIZE="2"><B>SAN DIEGO, CALIFORNIA</B></FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>92121</B></FONT></TD></TR>
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<TD VALIGN="top" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>(Address of Principal Executive Offices)</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>(Zip Code)</B></FONT></TD></TR>
</TABLE> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>(858) 558-2871 </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
FACE="Times New Roman" SIZE="1"><B>(Registrant&#146;s telephone number, including area code) </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>N/A </B></FONT></P> <P
STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>(Former name or former address, if changed since last report) </B></FONT></P> <P
STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P><center> <P STYLE="line-height:6px;margin-top:0px;margin-bottom:2px;border-bottom:1pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:6px;margin-bottom:0px"><FONT
FACE="Times New Roman" SIZE="2">Check the appropriate box below if the Form 8-K is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions: </FONT></P> <P
STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><FONT FACE="WINGDINGS">&#168;</FONT></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) </FONT></TD></TR></TABLE> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>

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<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><FONT FACE="WINGDINGS">&#168;</FONT></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) </FONT></TD></TR></TABLE> <P
STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><FONT FACE="WINGDINGS">&#168;</FONT></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) </FONT></TD></TR></TABLE> <P
STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><FONT FACE="WINGDINGS">&#168;</FONT></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) </FONT></TD></TR></TABLE> <P
STYLE="font-size:24px;margin-top:0px;margin-bottom:0px">&nbsp;</P> <P STYLE="line-height:0px;margin-top:0px;margin-bottom:0px;border-bottom:0.5pt solid #000000">&nbsp;</P> <P
STYLE="line-height:3px;margin-top:0px;margin-bottom:2px;border-bottom:0.5pt solid #000000">&nbsp;</P>

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<TD WIDTH="10%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><B>Item&nbsp;1.01.</B></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2"><B>Entry into a Material Definitive Agreement </B></FONT></TD></TR></TABLE> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">On
March&nbsp;24, 2009, ACADIA Pharmaceuticals Inc. and Meiji Seika Kaisha, Ltd. entered into a collaboration and license agreement (the &#147;Agreement&#148;) to develop and commercialize a novel class of pro-cognitive drugs to treat patients with
schizophrenia and related disorders. Pursuant to the terms of the Agreement, Meiji Seika has the right to develop and commercialize the licensed compounds in Japan and several other Asian countries. The collaboration will focus on developing a
product candidate, which was discovered by ACADIA and has been nominated by the parties for IND-track development. Pursuant to the terms of the Agreement, ACADIA is eligible to receive up to $25 million in aggregate payments, including $3 million in
license fees and up to $22 million in potential development and regulatory milestone payments, as well as royalties on product sales in the Asian territory. Meiji Seika is responsible for the first $15 million of development expenses.The companies
will share the remaining expenses through clinical proof-of-concept, subject to possible adjustment in the event ACADIA further licenses the program outside of the Asian market. Meiji Seika is responsible for all costs associated with the
development, manufacturing and commercialization of the product in the Asian territory after proof-of-concept. Meiji Seika is eligible to share a portion of any product-related revenues received by ACADIA in the rest of the world. </FONT></P> <P
STYLE="margin-top:18px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>Forward-Looking Statements </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">Certain statements in
this report that are not historical facts are forward-looking statements that involve a number of risks and uncertainties. Such forward-looking statements include statements relating to the activities expected to occur in connection with
ACADIA&#146;s collaboration with Meiji Seika, including license fees and milestone and royalty payments ACADIA is eligible to receive under the Agreement. These statements are only predictions based on current information and expectations and
involve a number of risks and uncertainties. Actual events or results may differ materially from those projected in any of such statements due to various factors, including the risks and uncertainties inherent in drug discovery, development and
commercialization, and collaborations with others. For a discussion of these and other factors, please refer to ACADIA&#146;s annual report on Form 10-K for the year ended December&nbsp;31, 2008 as well as other subsequent filings with the
Securities and Exchange Commission. You are cautioned not to place undue reliance on these forward-looking statements, which speak only as of the date hereof. This caution is made under the safe harbor provisions of the Private Securities Litigation
Reform Act of 1995. All forward-looking statements are qualified in their entirety by this cautionary statement and ACADIA undertakes no obligation to revise or update this report to reflect events or circumstances after the date hereof. </FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">1. </FONT></P>


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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>SIGNATURES </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT
FACE="Times New Roman" SIZE="2">Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. </FONT></P> <P
STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TD VALIGN="top" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2">ACADIA Pharmaceuticals Inc.</FONT></TD></TR>
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<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">Date: March&nbsp;25, 2008</FONT></TD>
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<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">By:</FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top" STYLE="BORDER-BOTTOM:1px solid #000000"><FONT FACE="Times New Roman" SIZE="2">/s/ Thomas H. Aasen</FONT></TD></TR>
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<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">Thomas H. Aasen</FONT></TD></TR>
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<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">Vice President, Chief Financial Officer, Treasurer, and Secretary</FONT></TD></TR>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">2. </FONT></P>

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