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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>As filed with the Securities and Exchange Commission on June&nbsp;16, 2015 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="right"><B>Registration No.&nbsp;333-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </B></P>
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<P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="margin-top:4pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>UNITED STATES </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>SECURITIES AND EXCHANGE COMMISSION </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B>Washington, D.C. 20549 </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>FORM S-8
</B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:18pt; font-family:Times New Roman" ALIGN="center"><B>REGISTRATION STATEMENT </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B><I>UNDER </I></B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:12pt; font-family:Times New Roman" ALIGN="center"><B><I>THE
SECURITIES ACT OF 1933 </I></B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center> <P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:24pt; font-family:Times New Roman" ALIGN="center"><B>ARENA PHARMACEUTICALS, INC. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>(Exact name of registrant as specified in its charter) </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="top" ALIGN="center"><B>Delaware</B></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="top" ALIGN="center"><B>23-2908305</B></TD></TR>
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<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(State or other jurisdiction of</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>incorporation or organization)</B></P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(I.R.S. Employer</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Identification No.)</B></P></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>6154 Nancy Ridge Drive </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>San Diego, California 92121 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Address of principal executive offices) (Zip code) </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Arena
Pharmaceuticals, Inc. 2009 Employee Stock Purchase Plan, as amended </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Full title of the plan) </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Steven W. Spector, Esq. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Executive Vice President, General Counsel and Secretary </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>6154 Nancy Ridge Drive </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>San Diego, California 92121 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>858.453.7200 </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>(Name and
address of agent for service) (Telephone number, including area code, of agent for service) </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B><I>Copies to:
</I></B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Steven M. Przesmicki, Esq. </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>Cooley LLP </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>4401 Eastgate
Mall </B></P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>San Diego, California 92121 </B></P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>858.550.6000 </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><center>
<P STYLE="line-height:6.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1.00pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Indicate by check mark whether
the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of &#147;large accelerated filer,&#148; &#147;accelerated filer&#148; and &#147;smaller reporting
company&#148; in Rule 12b-2 of the Exchange Act. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD VALIGN="bottom">Large&nbsp;accelerated&nbsp;filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#120;</FONT></TD>
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<TD VALIGN="bottom">Accelerated&nbsp;filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></TD></TR>
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<TD VALIGN="bottom">Non-accelerated filer</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT>&nbsp;&nbsp;(Do not check if a smaller reporting company)</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom">Smaller&nbsp;reporting&nbsp;company</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></TD></TR>
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<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>CALCULATION OF REGISTRATION FEE </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD COLSPAN="9" VALIGN="bottom"> <P STYLE="border-top:1.00px solid #000000">&nbsp;</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center">Title of Securities</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center">to be Registered</P></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">Amount to be<BR>Registered (1)</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center">Proposed Maximum</P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center">Offering</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center">Price per Share (2)</P></TD>

<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center">Proposed Maximum</P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center">Aggregate</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center">Offering Price (2)</P></TD>

<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center">Amount of</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center">Registration Fee</P></TD></TR>
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<TD VALIGN="top" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-left:1.00em; text-indent:-1.00em; font-size:10pt; font-family:Times New Roman">Common Stock, par value $0.0001 per share, issuable under the Arena Pharmaceuticals, Inc. 2009
Employee Stock Purchase Plan, as amended</P></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">987,961&nbsp;shares&nbsp;(3)</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$4.14</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$4,090,158.54</TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000">$475.28</TD></TR>
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<TD COLSPAN="9" VALIGN="bottom"> <P STYLE="border-top:1.00px solid #000000">&nbsp;</P></TD></TR>
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<TD COLSPAN="9" VALIGN="bottom"> <P STYLE="border-top:1.00px solid #000000">&nbsp;</P></TD></TR>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left">(1)</TD>
<TD ALIGN="left" VALIGN="top">Pursuant to Rule 416(a) under the Securities Act of 1933, as amended (the &#147;Securities Act&#148;), this Registration Statement shall also cover any additional shares of Registrant&#146;s Common Stock that, with
respect to the shares registered hereunder, become issuable under the Arena Pharmaceuticals, Inc. 2009 Employee Stock Purchase Plan, as amended (&#147;Amended 2009 ESPP&#148;), by reason of any stock dividend, stock split, recapitalization or other
similar transaction effected without receipt of consideration that increases the number of outstanding shares of Registrant&#146;s Common Stock. </TD></TR></TABLE>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left">(2)</TD>
<TD ALIGN="left" VALIGN="top">Estimated solely for the purpose of calculating the amount of the registration fee pursuant to Rule 457(h) under the Securities Act. The offering price per share and aggregate offering price are based upon the average
of the high and low prices of Registrant&#146;s Common Stock on June&nbsp;15, 2015, as reported on the NASDAQ Global Select Market. </TD></TR></TABLE>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left">(3)</TD>
<TD ALIGN="left" VALIGN="top">Represents the shares of Registrant&#146;s Common Stock added to the shares previously authorized for issuance under the Arena Pharmaceuticals, Inc. 2009 Employee Stock Purchase Plan pursuant to the approval of an
amendment to such plan at the Registrant&#146;s 2015 Annual Meeting of Stockholders on June&nbsp;12, 2015. </TD></TR></TABLE> <P STYLE="font-size:10pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:1.0pt;margin-top:0pt;margin-bottom:0pt;border-bottom:1px solid #000000">&nbsp;</P> <P STYLE="line-height:3.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000">&nbsp;</P>

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 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>PART II </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>INFORMATION REQUIRED IN THE REGISTRATION STATEMENT </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="10%" VALIGN="top" ALIGN="left"><B>Item&nbsp;3.</B></TD>
<TD ALIGN="left" VALIGN="top"><B>Incorporation of Documents by Reference. </B></TD></TR></TABLE> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The following documents filed by Arena
Pharmaceuticals, Inc. (&#147;Arena&#148;, the &#147;Company&#148; or the &#147;Registrant&#148;) with the Securities and Exchange Commission (the &#147;SEC&#148;) are incorporated by reference into this Registration Statement (other than information
furnished under Item&nbsp;2.02 or Item&nbsp;7.01 of Form&nbsp;8-K or other portions of documents filed with the SEC which are furnished, but not filed, pursuant to applicable rules promulgated by the SEC): </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(a) The Company&#146;s Annual Report on Form 10-K for the fiscal year ended December&nbsp;31, 2014, which was filed with the SEC on March&nbsp;2, 2015; </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(b) The Company&#146;s Quarterly Report on Form 10-Q for the fiscal quarter ended March&nbsp;31, 2015, which was filed with the SEC on May&nbsp;11, 2015; and
the Company&#146;s Current Reports on Form 8-K filed with the SEC on January&nbsp;9, 2015,&nbsp;January&nbsp;12, 2015,&nbsp;January&nbsp;20, 2015,&nbsp;January&nbsp;23, 2015,&nbsp;February&nbsp;3, 2015,&nbsp;April&nbsp;10, 2015,&nbsp;April&nbsp;30,
2015, and June&nbsp;16, 2015; and </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">(c) The description of Registrant&#146;s Common Stock contained in the Registrant&#146;s registration statement on
Form&nbsp;8-A filed with the SEC on July&nbsp;26, 2000, including any amendment or reports filed for the purpose of updating such description. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">All reports and other documents subsequently filed with the SEC by the Company pursuant to Sections&nbsp;13(a), 13(c), 14 or 15(d) of the
Securities Exchange Act of 1934, as amended (the &#147;Exchange Act&#148;), prior to the filing of a post-effective amendment which indicates that all securities offered have been sold or which deregisters all securities then remaining unsold shall
be deemed to be incorporated by reference in this Registration Statement and to be a part hereof from the date of the filing of such reports and documents. Any statement contained in a document incorporated by reference herein shall be deemed to be
modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference herein modifies or supersedes
such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement. </P> <P STYLE="font-size:18pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="10%" VALIGN="top" ALIGN="left"><B>Item&nbsp;6.</B></TD>
<TD ALIGN="left" VALIGN="top"><B>Indemnification of Directors and Officers. </B></TD></TR></TABLE> <P STYLE="margin-top:6pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The Registrant&#146;s Certificate of
Incorporation and Bylaws provide for indemnification of the Registrant&#146;s directors and officers to the fullest extent permitted by law. Insofar as indemnification for liabilities under the Securities Act may be permitted to directors, officers
or controlling persons of the Registrant pursuant to the Registrant&#146;s Certificate of Incorporation, Bylaws and the Delaware General Corporation Law (the &#147;DGCL&#148;), the Registrant has been informed that in the opinion of the SEC such
indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Section&nbsp;102(b)(7)&nbsp;of the DGCL provides that a certificate of incorporation may include a provision which eliminates or limits the
personal liability of a director to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except for liability (i)&nbsp;for any breach of the director&#146;s duty of loyalty to the corporation or its
stockholders, (ii)&nbsp;for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii)&nbsp;under Section&nbsp;174 of the DGCL, relating to prohibited dividends or distributions or the repurchase
or redemption of stock or (iv)&nbsp;for any transaction from which the director derives an improper personal benefit. The Registrant&#146;s Certificate of Incorporation includes such a provision. As a result of this provision, the Registrant and its
stockholders may be unable to obtain monetary damages from a director for breach of his or her duty of care. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">As permitted under the DGCL,
the Registrant has entered into indemnification agreements with each of its directors and executive officers that require the Registrant to indemnify such persons against any and all expenses </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">1 </P>


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(including attorneys&#146;, witness or other professional fees), and, unless in connection with a proceeding by or in the right of the Registrant, any and all judgments, fines and amounts paid in
settlement, actually and reasonably incurred by such persons or on such persons&#146; behalf in connection with any proceeding, whether actual or threatened, to which any such person may be involved as a party or otherwise by reason of the fact that
such person is or was a director or an executive officer of the Registrant or is or was serving at the request of the Registrant as a director, officer, employee, agent or fiduciary of another enterprise, provided such person acted in good faith and
in a manner such person reasonably believed to be in or not opposed to the best interests of the Registrant and, with respect to any criminal proceeding, had no reasonable cause to believe such person&#146;s conduct was unlawful. Under these
agreements, the Registrant is not required to provide indemnification for certain matters, including: </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%">&nbsp;</TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">indemnification beyond that permitted by applicable law; </TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%">&nbsp;</TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">except as provided in the indemnification agreements, an accounting of profits made from the purchase and sale (or sale and purchase) by such director or executive officer of securities of the Registrant within the
meaning of Section&nbsp;16(b)&nbsp;of the Exchange Act or similar provisions of state statutory law or common law; </TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%">&nbsp;</TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">except as provided in the indemnification agreements, any reimbursement of the Registrant by such director or executive officer of any bonus or other incentive-based or equity-based compensation or of any profits
realized by such director or executive officer from the sale of securities of the Registrant, as required in each case under the Exchange Act; or </TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="5%">&nbsp;</TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">except as provided in the indemnification agreements, in connection with any proceeding initiated by such director or executive officer, unless (i)&nbsp;the Registrant&#146;s Board of Directors authorized the proceeding
prior to its initiation or (ii)&nbsp;the Registrant provides the indemnification, in its sole discretion, pursuant to the powers vested in the Registrant under applicable law. </TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The indemnification agreements also set forth certain procedures, presumptions and remedies that will apply in the event of a claim for
indemnification thereunder. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">The Registrant has also obtained policies that insure the Registrant&#146;s directors and executive officers
against certain liabilities they may incur in their capacity as directors and executive officers of the Registrant. </P> <P STYLE="font-size:18pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="10%" VALIGN="top" ALIGN="left"><B>Item&nbsp;8.</B></TD>
<TD ALIGN="left" VALIGN="top"><B>Exhibits. </B></TD></TR></TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>
<TD></TD>
<TD VALIGN="bottom" WIDTH="5%"></TD>
<TD WIDTH="92%"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Exhibit</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1.00pt solid #000000; width:28.45pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Number</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="border-bottom:1.00pt solid #000000; width:39.50pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Description</B></P></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Fifth Amended and Restated Certificate of Incorporation of Arena (incorporated by reference to Exhibit&nbsp;3.1 to Arena&#146;s Quarterly Report on Form&nbsp;10-Q for the quarter ended June&nbsp;30, 2002, filed with the Securities
and Exchange Commission on August&nbsp;14, 2002, Commission File&nbsp;No.&nbsp;000-31161)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Certificate of Amendment of the Fifth Amended and Restated Certificate of Incorporation of Arena (incorporated by reference to Exhibit 4.2 to Arena&#146;s registration statement on Form S-8 filed with the Securities and Exchange
Commission on June 28, 2006, Commission File No. 333-135398)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.3</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Certificate of Amendment No. 2 of the Fifth Amended and Restated Certificate of Incorporation of Arena, as amended (incorporated by reference to Exhibit&nbsp;4.3 to Arena&#146;s registration statement on Form&nbsp;S-8 filed with the
Securities and Exchange Commission on June&nbsp;30, 2009, Commission File&nbsp;No.&nbsp;333-160329)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.4</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Certificate of Amendment No. 3 of the Fifth Amended and Restated Certificate of Incorporation of Arena, as amended (incorporated by reference to Exhibit&nbsp;3.4 to Arena&#146;s registration statement on Form&nbsp;S-8 filed with the
Securities and Exchange Commission on June&nbsp;20, 2012, Commission File&nbsp;No.&nbsp;333-182238)</TD></TR></TABLE>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">2 </P>


<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>
<TD></TD>
<TD VALIGN="bottom" WIDTH="5%"></TD>
<TD WIDTH="92%"></TD></TR>

<TR STYLE="font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Exhibit</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1.00pt solid #000000; width:28.45pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Number</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="border-bottom:1.00pt solid #000000; width:39.50pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Description</B></P></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.5</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Amended and Restated Bylaws of Arena (incorporated by reference to Exhibit&nbsp;3.1 to Arena&#146;s Current Report on Form&nbsp;8-K filed with the Securities and Exchange Commission on October&nbsp;9, 2014, Commission File
No.&nbsp;000-31161)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.6</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Form of common stock certificate (incorporated by reference to Exhibit 4.2 to Arena&#146;s registration statement on Form S-1, as amended, filed with the Securities and Exchange Commission on July 19, 2000, Commission File No.
333-35944)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;5.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Opinion of Cooley LLP</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Consent of Independent Registered Public Accounting Firm</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Consent of Cooley LLP (included as Exhibit&nbsp;5.1 to this Registration Statement)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>24.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Power of Attorney (included on the signature pages&nbsp;hereto)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Arena&#146;s 2009 Employee Stock Purchase Plan, as amended (incorporated by reference to Exhibit 10.1 to Arena&#146;s Current Report on Form 8-K filed with the Securities and Exchange Commission on June 16, 2015, Commission <FONT
STYLE="white-space:nowrap">File&nbsp;No.&nbsp;000-31161)</FONT></TD></TR>
</TABLE>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">3 </P>


<p Style='page-break-before:always'>
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<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="10%" VALIGN="top" ALIGN="left"><B>Item&nbsp;9.</B></TD>
<TD ALIGN="left" VALIGN="top"><B>Undertakings. </B></TD></TR></TABLE> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>1.</B> The undersigned Registrant hereby undertakes: </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"><B>(a)</B> To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement: </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:8%; font-size:10pt; font-family:Times New Roman"><B>(i)</B> To include any prospectus required by section 10(a)(3) of the Securities Act; </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:8%; font-size:10pt; font-family:Times New Roman"><B>(ii)</B> To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most
recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of
securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with
the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20% change in the maximum aggregate offering price set forth in the &#147;Calculation of Registration Fee&#148; table in the effective
registration statement. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:8%; font-size:10pt; font-family:Times New Roman"><B>(iii)</B> To include any material information with respect to the plan of distribution not previously
disclosed in the registration statement or any material change to such information in the registration statement; </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"><I>Provided,
however,</I> that paragraphs (a)(i) and (a)(ii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the SEC by the Registrant pursuant to
Section&nbsp;13 or Section&nbsp;15(d) of the Exchange Act that are incorporated by reference in the registration statement. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"><B>(b)
</B>That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered herein, and the offering of such securities at
that time shall be deemed to be the initial bona fide offering thereof.<B> </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"><B>(c) </B>To remove from registration by means of a
post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.<B> </B></P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"><B>(d)
</B>That, for the purpose of determining liability of the Registrant under the Securities Act to any purchaser in the initial distribution of the securities, the undersigned Registrant undertakes that in a primary offering of securities of the
undersigned Registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following
communications, the undersigned Registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser: <B> </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:8%; font-size:10pt; font-family:Times New Roman"><B>(i)</B> Any preliminary prospectus or prospectus of the undersigned Registrant relating to the offering required to be filed pursuant to
Rule 424; </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:8%; font-size:10pt; font-family:Times New Roman"><B>(ii)</B> Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned Registrant or used
or referred to by the undersigned Registrant; </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:8%; font-size:10pt; font-family:Times New Roman"><B>(iii)</B> The portion of any other free writing prospectus relating to the offering
containing material information about the undersigned Registrant or its securities provided by or on behalf of the undersigned Registrant; and </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:8%; font-size:10pt; font-family:Times New Roman"><B>(iv)</B> Any other communication that is an offer in the offering made by the undersigned Registrant to the purchaser. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>2.</B> The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the
Registrant&#146;s annual report pursuant to Section&nbsp;13(a) or Section&nbsp;15(d) of the </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">4 </P>


<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">
Exchange Act (and, where applicable, each filing of an employee benefit plan&#146;s annual report pursuant to Section&nbsp;15(d) of the Exchange Act) that is incorporated by reference in the
Registration Statement shall be deemed to be a new registration statement relating to the securities offered herein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><B>3.</B> Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the
event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or
proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a
court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue. </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">5 </P>


<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>SIGNATURES </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe
that it meets all of the requirements for filing on <FONT STYLE="white-space:nowrap">Form&nbsp;S-8</FONT> and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of San
Diego, State of California, on June&nbsp;16, 2015. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P><DIV ALIGN="right">
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>
<TD WIDTH="100%"></TD></TR>


<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"><B>A<SMALL>RENA</SMALL> P<SMALL>HARMACEUTICALS</SMALL>, I<SMALL>NC</SMALL>.</B></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Jack Lief</P></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">Jack Lief,</TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">President and Chief Executive Officer</TD></TR>
</TABLE></DIV>

<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>POWER OF ATTORNEY </B></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman"><B>K<SMALL>NOW</SMALL> A<SMALL>LL</SMALL> P<SMALL>ERSONS</SMALL> B<SMALL>Y</SMALL> T<SMALL>HESE</SMALL>
P<SMALL>RESENTS</SMALL></B><SMALL></SMALL>, that each person whose signature appears below constitutes and appoints Jack Lief and Steven W. Spector, and each of them, his or her true and lawful attorneys-in-fact and agents, each with full power of
substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement, and to file the same, with all
exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing
requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or either of them, or their or his
substitutes or substitute, may lawfully do or cause to be done by virtue hereof. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; text-indent:4%; font-size:10pt; font-family:Times New Roman">Pursuant to the requirements of the Securities Act of
1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated. </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt">


<TR>
<TD WIDTH="43%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="41%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="10%"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" ALIGN="center"><B>Signature</B></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center"><B>Date</B></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Jack Lief</P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Jack&nbsp;Lief,&nbsp;President,&nbsp;Chief&nbsp;Executive&nbsp;Officer&nbsp;and&nbsp;Director</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">(principal executive officer)</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">June&nbsp;16,&nbsp;2015</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Robert E. Hoffman</P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Robert E. Hoffman, Senior Vice President, Finance</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">and Chief
Financial Officer</P> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">(principal financial and accounting officer)</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">June&nbsp;16, 2015</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Dominic P. Behan</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Dominic P. Behan, Ph.D., D.Sc., Director</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">June&nbsp;16, 2015</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Donald D. Belcher</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Donald D. Belcher, Director</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">June&nbsp;16, 2015</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Scott H. Bice</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Scott H. Bice, Director</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">June&nbsp;16, 2015</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Harry F. Hixson</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Harry F. Hixson,&nbsp;Jr., Ph.D., Director</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">June&nbsp;16, 2015</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Tina S. Nova</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Tina S. Nova, Ph.D., Director</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">June&nbsp;16, 2015</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Phillip M. Schneider</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Phillip M. Schneider, Director</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">June&nbsp;16, 2015</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Christine A. White</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Christine A. White, M.D., Director</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">June&nbsp;16, 2015</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="16"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; border-bottom:1px solid #000000; font-size:10pt; font-family:Times New Roman">/s/ Randall E. Woods</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">Randall E. Woods, Director</P></TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="center">June&nbsp;16, 2015</TD></TR>
</TABLE>

<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center"><B>EXHIBIT INDEX </B></P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" ALIGN="center">


<TR>
<TD></TD>
<TD VALIGN="bottom" WIDTH="5%"></TD>
<TD WIDTH="92%"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Exhibit</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1.00pt solid #000000; width:28.45pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Number</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center"> <P STYLE="border-bottom:1.00pt solid #000000; width:39.50pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Description</B></P></TD></TR>


<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Fifth Amended and Restated Certificate of Incorporation of Arena (incorporated by reference to Exhibit&nbsp;3.1 to Arena&#146;s Quarterly Report on Form&nbsp;10-Q for the quarter ended June&nbsp;30, 2002, filed with the Securities
and Exchange Commission on August&nbsp;14, 2002, Commission File&nbsp;No.&nbsp;000-31161)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Certificate of Amendment of the Fifth Amended and Restated Certificate of Incorporation of Arena (incorporated by reference to Exhibit 4.2 to Arena&#146;s registration statement on Form S-8 filed with the Securities and Exchange
Commission on June 28, 2006, Commission File No. 333-135398)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.3</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Certificate of Amendment No. 2 of the Fifth Amended and Restated Certificate of Incorporation of Arena, as amended (incorporated by reference to Exhibit&nbsp;4.3 to Arena&#146;s registration statement on Form&nbsp;S-8 filed with the
Securities and Exchange Commission on June&nbsp;30, 2009, Commission File&nbsp;No.&nbsp;333-160329)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.4</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Certificate of Amendment No. 3 of the Fifth Amended and Restated Certificate of Incorporation of Arena, as amended (incorporated by reference to Exhibit&nbsp;3.4 to Arena&#146;s registration statement on Form&nbsp;S-8 filed with the
Securities and Exchange Commission on June&nbsp;20, 2012, Commission File&nbsp;No.&nbsp;333-182238)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.5</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Amended and Restated Bylaws of Arena (incorporated by reference to Exhibit&nbsp;3.1 to Arena&#146;s Current Report on Form&nbsp;8-K filed with the Securities and Exchange Commission on October&nbsp;9, 2014, Commission File
No.&nbsp;000-31161)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;4.6</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Form of common stock certificate (incorporated by reference to Exhibit 4.2 to Arena&#146;s registration statement on Form S-1, as amended, filed with the Securities and Exchange Commission on July 19, 2000, Commission File No.
333-35944)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>&nbsp;&nbsp;5.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Opinion of Cooley LLP</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Consent of Independent Registered Public Accounting Firm</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>23.2</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Consent of Cooley LLP (included as Exhibit&nbsp;5.1 to this Registration Statement)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>24.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Power of Attorney (included on the signature pages&nbsp;hereto)</TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top" NOWRAP>99.1</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">Arena&#146;s 2009 Employee Stock Purchase Plan, as amended (incorporated by reference to Exhibit 10.1 to Arena&#146;s Current Report on Form 8-K filed with the Securities and Exchange Commission on June 16, 2015, Commission <FONT
STYLE="white-space:nowrap">File&nbsp;No.&nbsp;000-31161)</FONT></TD></TR>
</TABLE>
</BODY></HTML>
[{"type": "S-8", "sequence": "1", "filename": "d945218ds8.htm", "description": "FORM S-8", "secsgml_size_bytes": 59659}]
{"company-data": {"conformed-name": "ARENA PHARMACEUTICALS INC", "cik": "0001080709", "assigned-sic": "2834", "irs-number": "232908305", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-204999", "film-number": "15934951"}, "business-address": {"street1": "6154 NANCY RIDGE DRIVE", "city": "SAN DIEGO", "state": "CA", "zip": "92121", "phone": "858-453-7200"}, "mail-address": {"street1": "6154 NANCY RIDGE DRIVE", "city": "SAN DIEGO", "state": "CA", "zip": "92121"}}
Form S-8
As filed with the Securities and Exchange Commission on June 16, 2015
Registration No. 333-
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM S-8
REGISTRATION STATEMENT
UNDER
THE
SECURITIES ACT OF 1933
ARENA PHARMACEUTICALS, INC.
(Exact name of registrant as specified in its charter)
Delaware
23-2908305
(State or other jurisdiction of
incorporation or organization)
(I.R.S. Employer
Identification No.)
6154 Nancy Ridge Drive
San Diego, California 92121
(Address of principal executive offices) (Zip code)
Arena
Pharmaceuticals, Inc. 2009 Employee Stock Purchase Plan, as amended
(Full title of the plan)
Steven W. Spector, Esq.
Executive Vice President, General Counsel and Secretary
6154 Nancy Ridge Drive
San Diego, California 92121
858.453.7200
(Name and
address of agent for service) (Telephone number, including area code, of agent for service)
Copies to:
Steven M. Przesmicki, Esq.
Cooley LLP
4401 Eastgate
Mall
San Diego, California 92121
858.550.6000
Indicate by check mark whether
the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting
company" in Rule 12b-2 of the Exchange Act.
Large accelerated filer
x
Accelerated filer
¨
Non-accelerated filer
¨
(Do not check if a smaller reporting company)
Smaller reporting company
¨
CALCULATION OF REGISTRATION FEE
Title of Securities
to be Registered
Amount to be
Registered (1)
Proposed Maximum
Offering
Price per Share (2)
Proposed Maximum
Aggregate
Offering Price (2)
Amount of
Registration Fee
Common Stock, par value $0.0001 per share, issuable under the Arena Pharmaceuticals, Inc. 2009
Employee Stock Purchase Plan, as amended
987,961 shares (3)
$4.14
$4,090,158.54
$475.28
(1)
Pursuant to Rule 416(a) under the Securities Act of 1933, as amended (the "Securities Act"), this Registration Statement shall also cover any additional shares of Registrant's Common Stock that, with
respect to the shares registered hereunder, become issuable under the Arena Pharmaceuticals, Inc. 2009 Employee Stock Purchase Plan, as amended ("Amended 2009 ESPP"), by reason of any stock dividend, stock split, recapitalization or other
similar transaction effected without receipt of consideration that increases the number of outstanding shares of Registrant's Common Stock.
(2)
Estimated solely for the purpose of calculating the amount of the registration fee pursuant to Rule 457(h) under the Securities Act. The offering price per share and aggregate offering price are based upon the average
of the high and low prices of Registrant's Common Stock on June 15, 2015, as reported on the NASDAQ Global Select Market.
(3)
Represents the shares of Registrant's Common Stock added to the shares previously authorized for issuance under the Arena Pharmaceuticals, Inc. 2009 Employee Stock Purchase Plan pursuant to the approval of an
amendment to such plan at the Registrant's 2015 Annual Meeting of Stockholders on June 12, 2015.
PART II
INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
Item 3.
Incorporation of Documents by Reference.
The following documents filed by Arena
Pharmaceuticals, Inc. ("Arena", the "Company" or the "Registrant") with the Securities and Exchange Commission (the "SEC") are incorporated by reference into this Registration Statement (other than information
furnished under Item 2.02 or Item 7.01 of Form 8-K or other portions of documents filed with the SEC which are furnished, but not filed, pursuant to applicable rules promulgated by the SEC):
(a) The Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2014, which was filed with the SEC on March 2, 2015;
(b) The Company's Quarterly Report on Form 10-Q for the fiscal quarter ended March 31, 2015, which was filed with the SEC on May 11, 2015; and
the Company's Current Reports on Form 8-K filed with the SEC on January 9, 2015, January 12, 2015, January 20, 2015, January 23, 2015, February 3, 2015, April 10, 2015, April 30,
2015, and June 16, 2015; and
(c) The description of Registrant's Common Stock contained in the Registrant's registration statement on
Form 8-A filed with the SEC on July 26, 2000, including any amendment or reports filed for the purpose of updating such description.
All reports and other documents subsequently filed with the SEC by the Company pursuant to Sections 13(a), 13(c), 14 or 15(d) of the
Securities Exchange Act of 1934, as amended (the "Exchange Act"), prior to the filing of a post-effective amendment which indicates that all securities offered have been sold or which deregisters all securities then remaining unsold shall
be deemed to be incorporated by reference in this Registration Statement and to be a part hereof from the date of the filing of such reports and documents. Any statement contained in a document incorporated by reference herein shall be deemed to be
modified or superseded for purposes of this Registration Statement to the extent that a statement contained herein or in any other subsequently filed document which also is or is deemed to be incorporated by reference herein modifies or supersedes
such statement. Any statement so modified or superseded shall not be deemed, except as so modified or superseded, to constitute a part of this Registration Statement.
Item 6.
Indemnification of Directors and Officers.
The Registrant's Certificate of
Incorporation and Bylaws provide for indemnification of the Registrant's directors and officers to the fullest extent permitted by law. Insofar as indemnification for liabilities under the Securities Act may be permitted to directors, officers
or controlling persons of the Registrant pursuant to the Registrant's Certificate of Incorporation, Bylaws and the Delaware General Corporation Law (the "DGCL"), the Registrant has been informed that in the opinion of the SEC such
indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable.
Section 102(b)(7) of the DGCL provides that a certificate of incorporation may include a provision which eliminates or limits the
personal liability of a director to the corporation or its stockholders for monetary damages for breach of fiduciary duty as a director, except for liability (i) for any breach of the director's duty of loyalty to the corporation or its
stockholders, (ii) for acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (iii) under Section 174 of the DGCL, relating to prohibited dividends or distributions or the repurchase
or redemption of stock or (iv) for any transaction from which the director derives an improper personal benefit. The Registrant's Certificate of Incorporation includes such a provision. As a result of this provision, the Registrant and its
stockholders may be unable to obtain monetary damages from a director for breach of his or her duty of care.
As permitted under the DGCL,
the Registrant has entered into indemnification agreements with each of its directors and executive officers that require the Registrant to indemnify such persons against any and all expenses
1
(including attorneys', witness or other professional fees), and, unless in connection with a proceeding by or in the right of the Registrant, any and all judgments, fines and amounts paid in
settlement, actually and reasonably incurred by such persons or on such persons' behalf in connection with any proceeding, whether actual or threatened, to which any such person may be involved as a party or otherwise by reason of the fact that
such person is or was a director or an executive officer of the Registrant or is or was serving at the request of the Registrant as a director, officer, employee, agent or fiduciary of another enterprise, provided such person acted in good faith and
in a manner such person reasonably believed to be in or not opposed to the best interests of the Registrant and, with respect to any criminal proceeding, had no reasonable cause to believe such person's conduct was unlawful. Under these
agreements, the Registrant is not required to provide indemnification for certain matters, including:
•
indemnification beyond that permitted by applicable law;
•
except as provided in the indemnification agreements, an accounting of profits made from the purchase and sale (or sale and purchase) by such director or executive officer of securities of the Registrant within the
meaning of Section 16(b) of the Exchange Act or similar provisions of state statutory law or common law;
•
except as provided in the indemnification agreements, any reimbursement of the Registrant by such director or executive officer of any bonus or other incentive-based or equity-based compensation or of any profits
realized by such director or executive officer from the sale of securities of the Registrant, as required in each case under the Exchange Act; or
•
except as provided in the indemnification agreements, in connection with any proceeding initiated by such director or executive officer, unless (i) the Registrant's Board of Directors authorized the proceeding
prior to its initiation or (ii) the Registrant provides the indemnification, in its sole discretion, pursuant to the powers vested in the Registrant under applicable law.
The indemnification agreements also set forth certain procedures, presumptions and remedies that will apply in the event of a claim for
indemnification thereunder.
The Registrant has also obtained policies that insure the Registrant's directors and executive officers
against certain liabilities they may incur in their capacity as directors and executive officers of the Registrant.
Item 8.
Exhibits.
Exhibit
Number
Description
4.1
Fifth Amended and Restated Certificate of Incorporation of Arena (incorporated by reference to Exhibit 3.1 to Arena's Quarterly Report on Form 10-Q for the quarter ended June 30, 2002, filed with the Securities
and Exchange Commission on August 14, 2002, Commission File No. 000-31161)
4.2
Certificate of Amendment of the Fifth Amended and Restated Certificate of Incorporation of Arena (incorporated by reference to Exhibit 4.2 to Arena's registration statement on Form S-8 filed with the Securities and Exchange
Commission on June 28, 2006, Commission File No. 333-135398)
4.3
Certificate of Amendment No. 2 of the Fifth Amended and Restated Certificate of Incorporation of Arena, as amended (incorporated by reference to Exhibit 4.3 to Arena's registration statement on Form S-8 filed with the
Securities and Exchange Commission on June 30, 2009, Commission File No. 333-160329)
4.4
Certificate of Amendment No. 3 of the Fifth Amended and Restated Certificate of Incorporation of Arena, as amended (incorporated by reference to Exhibit 3.4 to Arena's registration statement on Form S-8 filed with the
Securities and Exchange Commission on June 20, 2012, Commission File No. 333-182238)
2
Exhibit
Number
Description
4.5
Amended and Restated Bylaws of Arena (incorporated by reference to Exhibit 3.1 to Arena's Current Report on Form 8-K filed with the Securities and Exchange Commission on October 9, 2014, Commission File
No. 000-31161)
4.6
Form of common stock certificate (incorporated by reference to Exhibit 4.2 to Arena's registration statement on Form S-1, as amended, filed with the Securities and Exchange Commission on July 19, 2000, Commission File No.
333-35944)
5.1
Opinion of Cooley LLP
23.1
Consent of Independent Registered Public Accounting Firm
23.2
Consent of Cooley LLP (included as Exhibit 5.1 to this Registration Statement)
24.1
Power of Attorney (included on the signature pages hereto)
99.1
Arena's 2009 Employee Stock Purchase Plan, as amended (incorporated by reference to Exhibit 10.1 to Arena's Current Report on Form 8-K filed with the Securities and Exchange Commission on June 16, 2015, Commission
File No. 000-31161)
3
Item 9.
Undertakings.
1.
The undersigned Registrant hereby undertakes:
(a)
To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:
(i)
To include any prospectus required by section 10(a)(3) of the Securities Act;
(ii)
To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most
recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of
securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with
the SEC pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20% change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective
registration statement.
(iii)
To include any material information with respect to the plan of distribution not previously
disclosed in the registration statement or any material change to such information in the registration statement;
Provided,
however,
that paragraphs (a)(i) and (a)(ii) do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the SEC by the Registrant pursuant to
Section 13 or Section 15(d) of the Exchange Act that are incorporated by reference in the registration statement.
(b)
That, for the purpose of determining any liability under the Securities Act, each such post-effective amendment shall be deemed to be a new registration statement relating to the securities offered herein, and the offering of such securities at
that time shall be deemed to be the initial bona fide offering thereof.
(c)
To remove from registration by means of a
post-effective amendment any of the securities being registered which remain unsold at the termination of the offering.
(d)
That, for the purpose of determining liability of the Registrant under the Securities Act to any purchaser in the initial distribution of the securities, the undersigned Registrant undertakes that in a primary offering of securities of the
undersigned Registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following
communications, the undersigned Registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:
(i)
Any preliminary prospectus or prospectus of the undersigned Registrant relating to the offering required to be filed pursuant to
Rule 424;
(ii)
Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned Registrant or used
or referred to by the undersigned Registrant;
(iii)
The portion of any other free writing prospectus relating to the offering
containing material information about the undersigned Registrant or its securities provided by or on behalf of the undersigned Registrant; and
(iv)
Any other communication that is an offer in the offering made by the undersigned Registrant to the purchaser.
2.
The undersigned Registrant hereby undertakes that, for purposes of determining any liability under the Securities Act, each filing of the
Registrant's annual report pursuant to Section 13(a) or Section 15(d) of the
4
Exchange Act (and, where applicable, each filing of an employee benefit plan's annual report pursuant to Section 15(d) of the Exchange Act) that is incorporated by reference in the
Registration Statement shall be deemed to be a new registration statement relating to the securities offered herein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.
3.
Insofar as indemnification for liabilities arising under the Securities Act may be permitted to directors, officers and controlling persons of the
Registrant pursuant to the foregoing provisions, or otherwise, the Registrant has been advised that in the opinion of the SEC such indemnification is against public policy as expressed in the Securities Act and is, therefore, unenforceable. In the
event that a claim for indemnification against such liabilities (other than the payment by the Registrant of expenses incurred or paid by a director, officer or controlling person of the Registrant in the successful defense of any action, suit or
proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the Registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a
court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act and will be governed by the final adjudication of such issue.
5
SIGNATURES
Pursuant to the requirements of the Securities Act of 1933, as amended, the Registrant certifies that it has reasonable grounds to believe
that it meets all of the requirements for filing on
Form S-8
and has duly caused this Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of San
Diego, State of California, on June 16, 2015.
A
RENA
P
HARMACEUTICALS
, I
NC
.
/s/ Jack Lief
Jack Lief,
President and Chief Executive Officer
POWER OF ATTORNEY
K
NOW
A
LL
P
ERSONS
B
Y
T
HESE
P
RESENTS
, that each person whose signature appears below constitutes and appoints Jack Lief and Steven W. Spector, and each of them, his or her true and lawful attorneys-in-fact and agents, each with full power of
substitution and resubstitution, for him or her and in his or her name, place and stead, in any and all capacities, to sign any and all amendments (including post-effective amendments) to this Registration Statement, and to file the same, with all
exhibits thereto, and other documents in connection therewith, with the Securities and Exchange Commission, granting unto said attorneys-in-fact and agents, and each of them, full power and authority to do and perform each and every act and thing
requisite and necessary to be done in connection therewith, as fully to all intents and purposes as he or she might or could do in person, hereby ratifying and confirming all that said attorneys-in-fact and agents, or either of them, or their or his
substitutes or substitute, may lawfully do or cause to be done by virtue hereof.
Pursuant to the requirements of the Securities Act of
1933, this Registration Statement has been signed by the following persons in the capacities and on the dates indicated.
Signature
Date
/s/ Jack Lief
Jack Lief, President, Chief Executive Officer and Director
(principal executive officer)
June 16, 2015
/s/ Robert E. Hoffman
Robert E. Hoffman, Senior Vice President, Finance
and Chief
Financial Officer
(principal financial and accounting officer)
June 16, 2015
/s/ Dominic P. Behan
Dominic P. Behan, Ph.D., D.Sc., Director
June 16, 2015
/s/ Donald D. Belcher
Donald D. Belcher, Director
June 16, 2015
/s/ Scott H. Bice
Scott H. Bice, Director
June 16, 2015
/s/ Harry F. Hixson
Harry F. Hixson, Jr., Ph.D., Director
June 16, 2015
/s/ Tina S. Nova
Tina S. Nova, Ph.D., Director
June 16, 2015
/s/ Phillip M. Schneider
Phillip M. Schneider, Director
June 16, 2015
/s/ Christine A. White
Christine A. White, M.D., Director
June 16, 2015
/s/ Randall E. Woods
Randall E. Woods, Director
June 16, 2015
EXHIBIT INDEX
Exhibit
Number
Description
4.1
Fifth Amended and Restated Certificate of Incorporation of Arena (incorporated by reference to Exhibit 3.1 to Arena's Quarterly Report on Form 10-Q for the quarter ended June 30, 2002, filed with the Securities
and Exchange Commission on August 14, 2002, Commission File No. 000-31161)
4.2
Certificate of Amendment of the Fifth Amended and Restated Certificate of Incorporation of Arena (incorporated by reference to Exhibit 4.2 to Arena's registration statement on Form S-8 filed with the Securities and Exchange
Commission on June 28, 2006, Commission File No. 333-135398)
4.3
Certificate of Amendment No. 2 of the Fifth Amended and Restated Certificate of Incorporation of Arena, as amended (incorporated by reference to Exhibit 4.3 to Arena's registration statement on Form S-8 filed with the
Securities and Exchange Commission on June 30, 2009, Commission File No. 333-160329)
4.4
Certificate of Amendment No. 3 of the Fifth Amended and Restated Certificate of Incorporation of Arena, as amended (incorporated by reference to Exhibit 3.4 to Arena's registration statement on Form S-8 filed with the
Securities and Exchange Commission on June 20, 2012, Commission File No. 333-182238)
4.5
Amended and Restated Bylaws of Arena (incorporated by reference to Exhibit 3.1 to Arena's Current Report on Form 8-K filed with the Securities and Exchange Commission on October 9, 2014, Commission File
No. 000-31161)
4.6
Form of common stock certificate (incorporated by reference to Exhibit 4.2 to Arena's registration statement on Form S-1, as amended, filed with the Securities and Exchange Commission on July 19, 2000, Commission File No.
333-35944)
5.1
Opinion of Cooley LLP
23.1
Consent of Independent Registered Public Accounting Firm
23.2
Consent of Cooley LLP (included as Exhibit 5.1 to this Registration Statement)
24.1
Power of Attorney (included on the signature pages hereto)
99.1
Arena's 2009 Employee Stock Purchase Plan, as amended (incorporated by reference to Exhibit 10.1 to Arena's Current Report on Form 8-K filed with the Securities and Exchange Commission on June 16, 2015, Commission
File No. 000-31161)