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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>As filed with the Securities and Exchange Commission on June&nbsp;10, 2013 </B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Registration No.&nbsp;333-&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </B></FONT></P>
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<P STYLE="line-height:3px;margin-top:0px;margin-bottom:2px;border-bottom:0.5pt solid #000000">&nbsp;</P> <P STYLE="margin-top:4px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="5"><B>UNITED STATES </B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="5"><B>SECURITIES AND EXCHANGE COMMISSION </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="3"><B>Washington, D.C. 20549 </B></FONT></P> <P STYLE="font-size:12px;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:12px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="5"><B>FORM S-8
</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="5"><B>REGISTRATION STATEMENT </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="3"><B><I>UNDER </I></B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="3"><B><I>THE SECURITIES ACT OF 1933 </I></B></FONT></P>
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<P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="6"><B>ARENA PHARMACEUTICALS, INC. </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>(Exact name of registrant as specified in its charter) </B></FONT></P> <P STYLE="font-size:12px;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:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TD VALIGN="top" ALIGN="center"><FONT STYLE="font-family: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 STYLE="font-family:Times New Roman" SIZE="2"><B>23-2908305</B></FONT></TD></TR>
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<TD VALIGN="top" ALIGN="center"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>(State or other jurisdiction of</B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>incorporation or organization)</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 STYLE="font-family:Times New Roman" SIZE="1"><B>(I.R.S. Employer</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="1"><B>Identification No.)</B></FONT></P></TD></TR>
</TABLE> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>6154 Nancy Ridge Drive </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>San Diego, California 92121 </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>(Address of principal executive offices)
(Zip code) </B></FONT></P> <P STYLE="font-size:12px;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:12px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Arena Pharmaceuticals, Inc., 2013 Long-Term Incentive Plan </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="1"><B>(Full title of the plan) </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Steven W. Spector, Esq. </B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Executive Vice President, General Counsel and Secretary </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>6154 Nancy Ridge Drive </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>San Diego, California 92121 </B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>858.453.7200 </B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>(Name and address of agent for service) (Telephone number, including area code, of agent for service) </B></FONT></P>
<P STYLE="font-size:12px;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:12px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B><I>Copies to: </I></B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>Steven M. Przesmicki, Esq. </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Cooley LLP </B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>4401 Eastgate Mall </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>San Diego, California 92121 </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>858.550.6000 </B></FONT></P>
<P STYLE="font-size:12px;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:12px;margin-bottom:0px"><FONT
STYLE="font-family:Times New Roman" SIZE="2">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. </FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2">Large&nbsp;accelerated&nbsp;filer</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#120;</FONT></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2">Accelerated&nbsp;filer</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></FONT></TD></TR>
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<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
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<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2">Non-accelerated filer</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT>&nbsp;&nbsp;(Do not check if a smaller reporting company)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2">Smaller&nbsp;reporting&nbsp;company</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT STYLE="font-family:Times New Roman" SIZE="2"><FONT STYLE="FONT-FAMILY:WINGDINGS">&#168;</FONT></FONT></TD></TR>
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<P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>CALCULATION OF REGISTRATION FEE </B></FONT></P>
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<TD COLSPAN="9" VALIGN="bottom"> <P STYLE="border-top:1px solid #000000">&nbsp;</P></TD></TR>
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<TD VALIGN="bottom" ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Title of Securities</B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>to be Registered</B></FONT></P></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Amount to be<BR>Registered&nbsp;(1)</B></FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Proposed Maximum</B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Offering&nbsp;Price per<BR>Share (2)</B></FONT></P></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Proposed Maximum</B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Aggregate</B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Offering&nbsp;Price&nbsp;(2)</B></FONT></P></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Amount of</B></FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Registration&nbsp;Fee</B></FONT></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 STYLE="font-family:Times New Roman" SIZE="2">Common Stock, par value $0.0001 per share, issuable under the Arena
Pharmaceuticals,&nbsp;Inc., 2013 Long-Term Incentive Plan</FONT></P></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">43,581,606 shares (3)</FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">$8.70</FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">$379,159,973</FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-LEFT:1px solid #000000; BORDER-TOP:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top" NOWRAP ALIGN="center" STYLE="BORDER-TOP:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">$51,718</FONT></TD></TR>
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<TD COLSPAN="9" VALIGN="bottom"> <P STYLE="border-top:1px solid #000000">&nbsp;</P></TD></TR>
<TR STYLE="font-size:1px">
<TD COLSPAN="9" VALIGN="bottom"> <P STYLE="border-top:1px solid #000000">&nbsp;</P></TD></TR>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(1)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">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 2013 Long-Term Incentive Plan (the &#147;2013 LTIP&#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. </FONT></TD></TR></TABLE>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(2)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Estimated solely for the purpose of calculating the amount of the registration fee pursuant to Rule 457(h) under the Securities Act. The 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;6, 2013, as reported on the NASDAQ Global Select Market. </FONT></TD></TR></TABLE>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">(3)</FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Represents (i)&nbsp;26,720,370 shares of Registrant&#146;s Common Stock reserved for issuance under the 2013 LTIP, (ii)&nbsp;16,861,236&nbsp;shares of Registrant&#146;s
Common Stock which may be added to the 2013 LTIP upon the expiration, forfeiture or cash settlement of outstanding awards (the &#147;Outstanding Awards&#148;) granted under the Registrant&#146;s 2012 Long-Term Incentive Plan, 2009 Long-Term
Incentive Plan, 2006 Long-Term Incentive Plan, as amended, Amended and Restated 1998 Equity Compensation Plan, Amended and Restated 2000 Equity Compensation Plan and 2002 Equity Compensation Plan (collectively, the &#147;Prior Plans&#148;). The
Prior Plans have been terminated, and no further stock awards will be made under the Prior Plans. Any shares underlying the Outstanding Awards that expire, are forfeited or settled for cash have been allocated to the 2013 LTIP.
</FONT></TD></TR></TABLE> <P STYLE="font-size:10px;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>
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 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>PART II </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>INFORMATION REQUIRED IN THE REGISTRATION STATEMENT </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Item&nbsp;3. Incorporation of
Documents by Reference. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">The following documents filed by Arena Pharmaceuticals, Inc. (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): </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">(a)
The Company&#146;s Annual Report on Form 10-K for the fiscal year ended December&nbsp;31, 2012, which was filed with the SEC on March&nbsp;1, 2013; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT
STYLE="font-family:Times New Roman" SIZE="2">(b) The Company&#146;s Quarterly Report on Form 10-Q for the fiscal quarter ended March&nbsp;31, 2013, which was filed with the SEC on May&nbsp;9, 2013; and the Company&#146;s Current Reports on Form 8-K
filed with the SEC on January&nbsp;22, 2013,&nbsp;April&nbsp;1, 2013,&nbsp;April&nbsp;5, 2013,&nbsp;May&nbsp;2, 2013, and June&nbsp;7, 2013; and </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT
STYLE="font-family:Times New Roman" SIZE="2">(c) The description of Registrant&#146;s common stock contained in the Registrant&#146;s registration statement on Form 8-A filed with the SEC on July&nbsp;26, 2000, including any amendment or reports
filed for the purpose of updating such description. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">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. </FONT></P>
<P STYLE="margin-top:18px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Item&nbsp;6. Indemnification of Directors and Officers. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px; text-indent:4%"><FONT
STYLE="font-family:Times New Roman" SIZE="2">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. </FONT></P>
<P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">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 company 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. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">As permitted
under the DGCL, the Registrant has entered into indemnification agreements with each of its directors and certain of its executive officers that require the Registrant to indemnify such persons against any and all expenses (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
</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 STYLE="font-family:Times New Roman" SIZE="2">1 </FONT></P>


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

 <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">
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: </FONT></P> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="9%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="3%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">indemnification beyond that permitted by applicable law; </FONT></P></TD></TR></TABLE>
<P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="9%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="3%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">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; </FONT></P></TD></TR></TABLE>
<P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="9%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="3%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">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 </FONT></P></TD></TR></TABLE>
<P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="9%"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD WIDTH="3%" VALIGN="top" ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">&#149;</FONT></TD>
<TD WIDTH="1%" VALIGN="top"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left"><FONT STYLE="font-family:Times New Roman" SIZE="2">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. </FONT></P></TD></TR></TABLE> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">The indemnification agreements also set forth certain procedures, presumptions and remedies that will
apply in the event of a claim for indemnification thereunder. </FONT></P> <P STYLE="margin-top:18px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Item&nbsp;8. Exhibits. </B></FONT></P>
<P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TR>
<TD></TD>
<TD VALIGN="bottom" WIDTH="6%"></TD>
<TD WIDTH="92%"></TD></TR>
<TR>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Exhibit<BR>Number</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD></TR>


<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">4.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Fifth Amended and Restated Certificate of Incorporation of Arena (incorporated by reference to Exhibit 3.1 to Arena&#146;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)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">4.2</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">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)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">4.3</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">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&#146;s
registration statement on Form S-8 filed with the Securities and Exchange Commission on June 30, 2009, Commission File No. 333-160329)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">4.4</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">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&#146;s
registration statement on Form S-8 filed with the Securities and Exchange Commission on June 20, 2012, Commission File No. 333-182238)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">4.5</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Amended and Restated Bylaws of Arena (incorporated by reference to Exhibit 3.1 to Arena&#146;s current report on</FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Form 8-K filed with the Securities and Exchange Commission on October 4, 2007, Commission File No. 000-31161)</FONT></P></TD></TR>
</TABLE>
 <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 STYLE="font-family:Times New Roman" SIZE="2">2 </FONT></P>


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


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<TR>
<TD></TD>
<TD VALIGN="bottom" WIDTH="5%"></TD>
<TD WIDTH="92%"></TD></TR>
<TR>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Exhibit<BR>Number</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD></TR>


<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;4.6</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Form of common stock certificate (incorporated by reference to Exhibit 4.2 to Arena&#146;s registration statement on</FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Form S-1, as amended, filed with the Securities and Exchange Commission on July 19, 2000, Commission File No. 333-35944)</FONT></P></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;5.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Opinion of Steven W. Spector</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">23.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Consent of Independent Registered Public Accounting Firm</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">23.2</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Consent of Steven W. Spector (included as Exhibit&nbsp;5.1 to this Registration Statement)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">24.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Power of Attorney (included on the signature pages&nbsp;hereto)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">99.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Arena&#146;s 2013 Long-Term Incentive Plan</FONT></TD></TR>
</TABLE>
 <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 STYLE="font-family:Times New Roman" SIZE="2">3 </FONT></P>


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

 <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>Item&nbsp;9. Undertakings. </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px"><FONT
STYLE="font-family:Times New Roman" SIZE="2"><B>1. </B>The undersigned Registrant hereby undertakes: </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>(a) </B>To file,
during any period in which offers or sales are being made, a post-effective amendment to this registration statement: </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>(i)
</B>To include any prospectus required by section 10(a)(3) of the Securities Act; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT STYLE="font-family:Times New Roman" SIZE="2"><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 Commission 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. </FONT></P>
<P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT STYLE="font-family:Times New Roman" SIZE="2"><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; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2"><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 Commission 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. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2"><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. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2"><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. </FONT></P>
<P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2"><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: </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>(i) </B>Any preliminary prospectus or prospectus of the undersigned Registrant relating to the offering
required to be filed pursuant to Rule 424; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT STYLE="font-family:Times New Roman" SIZE="2"><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; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT STYLE="font-family:Times New Roman" SIZE="2"><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 </FONT></P>
<P STYLE="margin-top:12px;margin-bottom:0px; text-indent:8%"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>(iv) </B>Any other communication that is an offer in the offering made by the undersigned Registrant to the purchaser. </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 STYLE="font-family:Times New Roman" SIZE="2">4 </FONT></P>


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

 <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2"><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 Exchange Act (and, where applicable, each filing of an employee benefit plan&#146;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. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2"><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 Securities and Exchange Commission 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. </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 STYLE="font-family:Times New Roman" SIZE="2">5 </FONT></P>


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

 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>SIGNATURES </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT
STYLE="font-family:Times New Roman" SIZE="2">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&nbsp;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&nbsp;10, 2013. </FONT></P>
<P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P><DIV ALIGN="right">
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE">


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


<TR>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>A<SMALL>RENA</SMALL> P<SMALL>HARMACEUTICALS</SMALL>, I<SMALL>NC</SMALL>.</B></FONT></TD></TR>
<TR>
<TD HEIGHT="16"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Jack Lief</FONT></P></TD></TR>
<TR>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Jack Lief,</FONT></TD></TR>
<TR>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">President and Chief Executive Officer</FONT></TD></TR>
</TABLE></DIV>

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

 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>POWER OF ATTORNEY </B></FONT></P>
<P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2"><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>,<B></B> that each person whose signature appears below constitutes and appoints Jack Lief and Steven W. Spector, and each or any one of them, his or her true and lawful attorney-in-fact and agent, 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 any of them, or their or
his substitutes or substitute, may lawfully do or cause to be done by virtue hereof. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT STYLE="font-family:Times New Roman" SIZE="2">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. </FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
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<TR>
<TD WIDTH="37%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="58%"></TD></TR>
<TR>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Signature</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Date</B></FONT></TD></TR>


<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Jack Lief</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2">June&nbsp;10, 2013</FONT></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Jack Lief, Chairman, President and</FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT
STYLE="font-family:Times New Roman" SIZE="2">Chief Executive Officer</FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px"><FONT STYLE="font-family:Times New Roman" SIZE="2">(principal executive officer)</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Robert E. Hoffman</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2">June 10, 2013</FONT></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Robert E. Hoffman, Senior Vice President, Finance and Chief Financial Officer</FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px"><FONT
STYLE="font-family:Times New Roman" SIZE="2">(principal financial and accounting officer)</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Dominic P. Behan</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2">June 10, 2013</FONT></TD></TR>
<TR>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Dominic P. Behan, Ph.D., Director</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Donald D. Belcher</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2">June 10, 2013</FONT></TD></TR>
<TR>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Donald D. Belcher, Director</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Scott H. Bice</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2">June 10, 2013</FONT></TD></TR>
<TR>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Scott H. Bice, Director</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Harry F. Hixson</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2">June 10, 2013</FONT></TD></TR>
<TR>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Harry F. Hixson,&nbsp;Jr., Ph.D., Director</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Tina S. Nova</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2">June 10, 2013</FONT></TD></TR>
<TR>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Tina S. Nova, Ph.D., Director</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Phillip M. Schneider</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2">June 10, 2013</FONT></TD></TR>
<TR>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Phillip M. Schneider, Director</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
</TABLE>

<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">


<TR>
<TD WIDTH="37%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="58%"></TD></TR>
<TR>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Signature</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Date</B></FONT></TD></TR>


<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Christine A. White</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2">June&nbsp;10, 2013</FONT></TD></TR>
<TR>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Christine A. White, M.D., Director</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:1px;border-bottom:1px solid #000000"><FONT STYLE="font-family:Times New Roman" SIZE="2">/s/ Randall E. Woods</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2">June 10, 2013</FONT></TD></TR>
<TR>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Randall E. Woods, Director</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD></TR>
</TABLE>

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

 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="2"><B>EXHIBIT INDEX </B></FONT></P>
<P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" STYLE="BORDER-COLLAPSE:COLLAPSE" ALIGN="center">


<TR>
<TD></TD>
<TD VALIGN="bottom" WIDTH="5%"></TD>
<TD WIDTH="92%"></TD></TR>
<TR>
<TD VALIGN="bottom" ALIGN="center"><FONT STYLE="font-family:Times New Roman" SIZE="1"><B>Exhibit<BR>Number</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD></TR>


<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;4.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Fifth Amended and Restated Certificate of Incorporation of Arena (incorporated by reference to Exhibit 3.1 to Arena&#146;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)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;4.2</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">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)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;4.3</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">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&#146;s
registration statement on Form S-8 filed with the Securities and Exchange Commission on June 30, 2009, Commission File No. 333-160329)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;4.4</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">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&#146;s
registration statement on Form S-8 filed with the Securities and Exchange Commission on June 20, 2012, Commission File No. 333-182238)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;4.5</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Amended and Restated Bylaws of Arena (incorporated by reference to Exhibit 3.1 to Arena&#146;s current report on</FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Form 8-K filed with the Securities and Exchange Commission on October 4, 2007, Commission File No. 000-31161)</FONT></P></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;4.6</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Form of common stock certificate (incorporated by reference to Exhibit 4.2 to Arena&#146;s registration statement on</FONT></P>
<P STYLE="margin-top:0px;margin-bottom:0px"><FONT STYLE="font-family:Times New Roman" SIZE="2">Form S-1, as amended, filed with the Securities and Exchange Commission on July 19, 2000, Commission</FONT></P>
<P STYLE="margin-top:0px;margin-bottom:1px"><FONT STYLE="font-family:Times New Roman" SIZE="2">File No. 333-35944)</FONT></P></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">&nbsp;&nbsp;5.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Opinion of Steven W. Spector</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">23.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Consent of Independent Registered Public Accounting Firm</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">23.2</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Consent of Steven W. Spector (included as Exhibit&nbsp;5.1 to this Registration Statement)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">24.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Power of Attorney (included on the signature pages&nbsp;hereto)</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT STYLE="font-family:Times New Roman" SIZE="2">99.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT STYLE="font-family:Times New Roman" SIZE="2">Arena&#146;s 2013 Long-Term Incentive Plan</FONT></TD></TR>
</TABLE>
</BODY></HTML>
[{"type": "S-8", "sequence": "1", "filename": "d550939ds8.htm", "description": "FORM S-8", "secsgml_size_bytes": 61901}]
{"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": "333-189213", "film-number": "13903581"}, "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 10, 2013
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., 2013 Long-Term Incentive Plan
(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., 2013 Long-Term Incentive Plan
43,581,606 shares (3)
$8.70
$379,159,973
$51,718
(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 2013 Long-Term Incentive Plan (the "2013 LTIP") 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 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 6, 2013, as reported on the NASDAQ Global Select Market.
(3)
Represents (i) 26,720,370 shares of Registrant's Common Stock reserved for issuance under the 2013 LTIP, (ii) 16,861,236 shares of Registrant's
Common Stock which may be added to the 2013 LTIP upon the expiration, forfeiture or cash settlement of outstanding awards (the "Outstanding Awards") granted under the Registrant's 2012 Long-Term Incentive Plan, 2009 Long-Term
Incentive Plan, 2006 Long-Term Incentive Plan, as amended, Amended and Restated 1998 Equity Compensation Plan, Amended and Restated 2000 Equity Compensation Plan and 2002 Equity Compensation Plan (collectively, the "Prior Plans"). The
Prior Plans have been terminated, and no further stock awards will be made under the Prior Plans. Any shares underlying the Outstanding Awards that expire, are forfeited or settled for cash have been allocated to the 2013 LTIP.
PART II
INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
Item 3. Incorporation of
Documents by Reference.
The following documents filed by Arena Pharmaceuticals, Inc. (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, 2012, which was filed with the SEC on March 1, 2013;
(b) The Company's Quarterly Report on Form 10-Q for the fiscal quarter ended March 31, 2013, which was filed with the SEC on May 9, 2013; and the Company's Current Reports on Form 8-K
filed with the SEC on January 22, 2013, April 1, 2013, April 5, 2013, May 2, 2013, and June 7, 2013; 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 company 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 certain of its executive officers that require the Registrant to indemnify such persons against any and all expenses (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
1
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.
Item 8. Exhibits.
Exhibit
Number
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 4, 2007, Commission File No. 000-31161)
2
Exhibit
Number
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 Steven W. Spector
23.1
Consent of Independent Registered Public Accounting Firm
23.2
Consent of Steven W. Spector (included as Exhibit 5.1 to this Registration Statement)
24.1
Power of Attorney (included on the signature pages hereto)
99.1
Arena's 2013 Long-Term Incentive Plan
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 Commission 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 Commission 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.
4
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 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 Securities and Exchange Commission 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 10, 2013.
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 or any one of them, his or her true and lawful attorney-in-fact and agent, 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 any 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
June 10, 2013
Jack Lief, Chairman, President and
Chief Executive Officer
(principal executive officer)
/s/ Robert E. Hoffman
June 10, 2013
Robert E. Hoffman, Senior Vice President, Finance and Chief Financial Officer
(principal financial and accounting officer)
/s/ Dominic P. Behan
June 10, 2013
Dominic P. Behan, Ph.D., Director
/s/ Donald D. Belcher
June 10, 2013
Donald D. Belcher, Director
/s/ Scott H. Bice
June 10, 2013
Scott H. Bice, Director
/s/ Harry F. Hixson
June 10, 2013
Harry F. Hixson, Jr., Ph.D., Director
/s/ Tina S. Nova
June 10, 2013
Tina S. Nova, Ph.D., Director
/s/ Phillip M. Schneider
June 10, 2013
Phillip M. Schneider, Director
Signature
Date
/s/ Christine A. White
June 10, 2013
Christine A. White, M.D., Director
/s/ Randall E. Woods
June 10, 2013
Randall E. Woods, Director
EXHIBIT INDEX
Exhibit
Number
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 4, 2007, 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 Steven W. Spector
23.1
Consent of Independent Registered Public Accounting Firm
23.2
Consent of Steven W. Spector (included as Exhibit 5.1 to this Registration Statement)
24.1
Power of Attorney (included on the signature pages hereto)
99.1
Arena's 2013 Long-Term Incentive Plan