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<P ALIGN="CENTER"><FONT SIZE=5><B>SECURITIES AND EXCHANGE COMMISSION<BR>  </B></FONT><FONT SIZE=2><B>WASHINGTON, DC 20549  </B></FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=5><B>FORM S-8<BR>  </B></FONT><FONT SIZE=2><B>REGISTRATION STATEMENT<BR>
UNDER<BR>
THE SECURITIES ACT OF 1933  </B></FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=5><B>ARENA PHARMACEUTICALS,&nbsp;INC.<BR>  </B></FONT><FONT SIZE=2>(Exact name of registrant as specified in its charter) </FONT></P>

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<TD WIDTH="49%" ALIGN="CENTER"><FONT SIZE=2><B>Delaware<BR> </B></FONT><FONT SIZE=2>(State or other jurisdiction<BR>
of incorporation or organization)</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="49%" ALIGN="CENTER"><FONT SIZE=2><B>23-2908305<BR> </B></FONT><FONT SIZE=2>(I.R.S. Employer Identification No.)</FONT></TD>
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<TD WIDTH="49%" ALIGN="CENTER"><BR><FONT SIZE=2><B>6166 Nancy Ridge Drive<BR>
San Diego, CA<BR> </B></FONT><FONT SIZE=2>(Address of principal executive offices)</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="49%" ALIGN="CENTER"><BR><FONT SIZE=2><B>92121<BR> </B></FONT><FONT SIZE=2>(Zip Code)</FONT></TD>
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<P ALIGN="CENTER"><FONT SIZE=5><B>2001 ARENA EMPLOYEE STOCK PURCHASE PLAN<BR>  </B></FONT><FONT SIZE=2>(Full title of the plan) </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B>Jack Lief<BR>
Arena Pharmaceuticals,&nbsp;Inc.<BR>
6166 Nancy Ridge Drive<BR>
San Diego, CA 92121<BR>  </B></FONT><FONT SIZE=2>(Name and address of agent for service) </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B>(858)&nbsp;453-7200<BR>  </B></FONT><FONT SIZE=2>(Telephone number, including area code, of agent for service) </FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=2><I>Copies of all communications to:<BR>  </I></FONT><FONT SIZE=2><B>General Counsel<BR>
Arena Pharmaceuticals,&nbsp;Inc.<BR>
6166 Nancy Ridge Drive<BR>
San Diego, CA 92121<BR>
(858)&nbsp;453-7200  </B></FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=2><B> CALCULATION OF REGISTRATION FEE  </B></FONT></P>

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<TD WIDTH="34%" ALIGN="CENTER" VALIGN="BOTTOM"><FONT SIZE=1><B>Title of Securities to be Registered</B></FONT></TD>
<TD WIDTH="1%" VALIGN="BOTTOM"><FONT SIZE=1>&nbsp;</FONT></TD>
<TD WIDTH="19%" ALIGN="CENTER" VALIGN="BOTTOM"><FONT SIZE=1><B>Amount to be Registered(1)</B></FONT></TD>
<TD WIDTH="1%" VALIGN="BOTTOM"><FONT SIZE=1>&nbsp;</FONT></TD>
<TD WIDTH="14%" ALIGN="CENTER" VALIGN="BOTTOM"><FONT SIZE=1><B>Proposed Maximum Offering Price<BR>
Per Share(2)</B></FONT></TD>
<TD WIDTH="1%" VALIGN="BOTTOM"><FONT SIZE=1>&nbsp;</FONT></TD>
<TD WIDTH="14%" ALIGN="CENTER" VALIGN="BOTTOM"><FONT SIZE=1><B>Proposed Maximum Aggregate<BR>
Offering Price(2)</B></FONT></TD>
<TD WIDTH="1%" VALIGN="BOTTOM"><FONT SIZE=1>&nbsp;</FONT></TD>
<TD WIDTH="14%" ALIGN="CENTER" VALIGN="BOTTOM"><FONT SIZE=1><B>Amount of<BR>
Registration Fee(3)</B></FONT></TD>
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<TD WIDTH="34%"><FONT SIZE=2>Common Stock, par value $0.0001 per share</FONT></TD>
<TD WIDTH="1%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="19%" ALIGN="CENTER"><FONT SIZE=2>1,000,000 shares</FONT></TD>
<TD WIDTH="1%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="14%" ALIGN="CENTER"><FONT SIZE=2>$25.905</FONT></TD>
<TD WIDTH="1%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="14%" ALIGN="CENTER"><FONT SIZE=2>$25,905,000</FONT></TD>
<TD WIDTH="1%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="14%" ALIGN="CENTER"><FONT SIZE=2>$6,476.25</FONT></TD>
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<DL compact>
<DT><FONT SIZE=2>(1)</FONT></DT><DD><FONT SIZE=2>This
Registration Statement shall cover shares of Common Stock of Arena Pharmaceuticals which are offered or sold pursuant to the plan named above. Pursuant to Rule&nbsp;416(a) of
the Securities Act of 1933, this registration statement shall also cover any additional shares of Common Stock which are offered or issued under the plan to prevent dilution resulting from stock
splits, stock dividends or similar transactions.
<BR><BR></FONT></DD><DT><FONT SIZE=2>(2)</FONT></DT><DD><FONT SIZE=2>Estimated
pursuant to paragraphs (c)&nbsp;and (h)&nbsp;of Rule&nbsp;457 solely for the purpose of calculating the registration fee, based upon the average of the reported high
and low sales prices for a share of Common Stock of Arena Pharmaceuticals,&nbsp;Inc. on June&nbsp;6, 2001 as reported in the Nasdaq National Market.
<BR><BR></FONT></DD><DT><FONT SIZE=2>(3)</FONT></DT><DD><FONT SIZE=2>Calculated
pursuant to Section&nbsp;6(b) of the Securities Act of 1933 as follows: proposed maximum aggregated offering price multiplied by $250.00/$1,000,000. </FONT></DD></DL>
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<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="de1519_part_i"> </A>
<A NAME="toc_de1519_1"> </A>
<BR></FONT><FONT SIZE=2><B>PART I    <BR>  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B>INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS  </B></FONT></P>

<P><FONT SIZE=2><A
NAME="de1519_item_1._plan_information"> </A>
<A NAME="toc_de1519_2"> </A></FONT> <FONT SIZE=2><B>Item 1. Plan Information    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;The documents containing the information specified in Part&nbsp;I of this Registration Statement will be sent or given to employees as specified by
Rule&nbsp;428(b)(1) of the Securities Act of 1933, as amended (the "Securities Act"). Such documents are not required to be and are not filed with the Securities and Exchange Commission (the
"Commission") either as part of this Registration Statement or as prospectuses or prospectus supplements pursuant to Rule&nbsp;424. These documents and the documents incorporated by reference in
this Registration Statement pursuant to Item 3 of Part&nbsp;II of this Form&nbsp;S-8, taken together, constitute a prospectus that meets the requirements of Section&nbsp;10(a) of the
Securities Act. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="de1519_part_ii"> </A>
<A NAME="toc_de1519_3"> </A>
<BR></FONT><FONT SIZE=2><B>PART II    <BR>  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B>INFORMATION REQUIRED IN THE REGISTRATION STATEMENT  </B></FONT></P>

<P><FONT SIZE=2><A
NAME="de1519_item_3._incorporation_of_documents_by_reference."> </A>
<A NAME="toc_de1519_4"> </A></FONT> <FONT SIZE=2><B>Item 3. Incorporation of Documents by Reference.    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;The following documents filed by Arena Pharmaceuticals,&nbsp;Inc. (the "Company") with the Commission, are incorporated by reference into this Registration
Statement: </FONT></P>

<UL>
<DL compact>
<DT><FONT SIZE=2>1.</FONT></DT><DD><FONT SIZE=2>The
Company's latest annual report on Form&nbsp;10-K for the fiscal year ended December&nbsp;31, 2000 filed pursuant to Section&nbsp;13(a) or 15(d) of the
Securities and Exchange Act of 1934 (the "Exchange Act");
<BR><BR></FONT></DD><DT><FONT SIZE=2>2.</FONT></DT><DD><FONT SIZE=2>All
other reports the Company has filed pursuant to Sections 13(a) or 15(d) of the Exchange Act since the end of the fiscal year coved by the document referred to in
(1)&nbsp;above; and
<BR><BR></FONT></DD><DT><FONT SIZE=2>3.</FONT></DT><DD><FONT SIZE=2>The
description of the shares of the Company's Common Stock contained in the Company's Registration Statement on Form&nbsp;8-A (File No.&nbsp;333-35944)
filed under the Exchange Act with the Commission on July&nbsp;26, 2000, which incorporates by reference the sections entitled "Prospectus Summary" and "Description of Capital Stock" in the
prospectus contained in the Registration Statement on Form&nbsp;S-1, filed July&nbsp;26, 2000, including all amendments and reports updating such description (File
No.&nbsp;333-35944). </FONT></DD></DL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;All
documents subsequently filed by the Company with the Commission pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act after the date of this Registration Statement,
but prior to the filing of a post-effective amendment to this Registration Statement which indicates that all securities offered by this Registration Statement have been sold or which
deregisters all such securities then remaining unsold, shall be deemed to be incorporated by reference into this Registration Statement. Each document incorporated by reference into this Registration
Statement shall be deemed to be a part of this Registration Statement from the date of the filing of such document with the Commission until the information contained therein is superseded or updated
by any subsequently filed document which is incorporated by reference into this Registration Statement or by any document which constitutes part of the prospectus relating to the 2001 Arena Employee
Stock Purchase Plan and meets the requirements of Section&nbsp;10(a) of the Securities Act. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Any
statement contained in a document incorporated by reference herein shall be deemed to be modified or superseded for purposes hereof to the extent that a statement contained herein
(or in any other subsequently filed document that is also incorporated by reference herein) modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed,
except as so modified or superseded, to constitute a part hereof. </FONT></P>


<P><FONT SIZE=2><A
NAME="de1519_item_4._description_of_securities."> </A>
<A NAME="toc_de1519_5"> </A>
<BR></FONT><FONT SIZE=2><B>Item 4. Description of Securities.    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Not Applicable. </FONT></P>

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<P><FONT SIZE=2><A
NAME="de1519_item_5._interests_of_named_experts_and_counsel."> </A>
<A NAME="toc_de1519_6"> </A>
<BR></FONT><FONT SIZE=2><B>Item 5. Interests of Named Experts and Counsel.    <BR>  </B></FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Not Applicable. </FONT></P>

<P><FONT SIZE=2><A
NAME="de1519_item_6._indemnification_of_directors_and_officers."> </A>
<A NAME="toc_de1519_7"> </A>
<BR></FONT><FONT SIZE=2><B>Item 6. Indemnification of Directors and Officers.    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;145 of the General Corporation Law of the State of Delaware (the "DGCL") permits a corporation, under specified circumstances, to
indemnify its directors, officers, employees or agents against expenses (including attorney's fees), judgments, fines and amounts paid in settlements actually and reasonably incurred by them in
connection with any action, suit or proceeding brought by third parties by reason of the fact that they were or are directors, officers, employees or agents of the corporation or were or are serving
at the request of the corporation as a director, officer, employee or agent of another corporation, if such directors, officers, employees, or agents acted in good faith and in a manner they
reasonably believed to be in or not opposed to the best interests of the corporation and, with respect to any criminal action or proceeding, had no reasonable cause to believe their conduct was
unlawful. In a derivative action, i.e., one by or in the right of the corporation, indemnification may be made only for expenses actually and reasonably incurred by directors, officers, employees or
agents in connection with the defense or settlement of an action or suit, and only with respect to a matter as to which they shall have acted in good faith and in a manner they reasonably believed to
be in or not opposed to the best interests of the corporation, except that no indemnification shall be made in respect of any claim, issue or matter as to which such person shall be adjudicated to be
liable to the corporation unless the court in which the action or suit was brought shall determine upon application that the defendant directors, officers, employees, or agents are fairly and
reasonably entitled to indemnification for such expenses in view of all of the circumstances of the case, despite such adjudication of liability. Expenses incurred (including attorney's fees) by an
officer or director in defending any civil, criminal, administrative or investigative action, suit or proceeding may be paid by the corporation in advance of the final disposition of such action, suit
or proceeding upon receipt of an undertaking by or on behalf of such director or officer to repay such amount if it shall ultimately be determined that he is not entitled to be indemnified by the
corporation. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Article&nbsp;V
of the Company's Fourth Restated and Amended Certificate of Incorporation, provides that a director shall not be personally liable to the Company or its stockholders
for monetary damages for breach of fiduciary duty as a director, except for liability (a)&nbsp;for any breach of the director's duty of loyalty to the Company or its stockholders, (b)&nbsp;for
acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (c)&nbsp;pursuant to Section&nbsp;174 of the DGCL, or (d)&nbsp;for any transaction from
which a director derived an improper personal benefit. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Article&nbsp;IV
of the Company's by-laws provides that it shall, to the full extent authorized or permitted by applicable law, indemnify any current or former director
or officer. Subject to applicable law, the Company may indemnify an employee or agent to the extent that the board of directors or stockholders may determine in its or their discretion. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;The
Company maintains an insurance policy containing customary terms and conditions for the purpose of insuring its directors and officers against certain losses incurred by them as a
result of claims based upon their actions or statements (including omissions to act or make statements) as directors and officers which may cover liabilities under the Securities Act. </FONT></P>


<P><FONT SIZE=2><A
NAME="de1519_item_7._exemption_from_registration_claimed."> </A>
<A NAME="toc_de1519_8"> </A>
<BR></FONT><FONT SIZE=2><B>Item 7. Exemption from Registration Claimed.    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Not Applicable. </FONT></P>

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<P><FONT SIZE=2><A
NAME="de1519_item_8._exhibits."> </A>
<A NAME="toc_de1519_9"> </A>
<BR></FONT><FONT SIZE=2><B>Item 8. Exhibits.    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;The following exhibits are filed herewith or incorporated by reference as part of this Registration Statement: </FONT></P>

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<TH WIDTH="8%" ALIGN="CENTER"><FONT SIZE=1><B>Exhibit No.</B></FONT><HR NOSHADE></TH>
<TH WIDTH="3%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="89%" ALIGN="CENTER"><FONT SIZE=1><B>Description</B></FONT><HR NOSHADE></TH>
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<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2>4.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2>Relevant portions of the Fourth Amended and Restated Certificate of Incorporation of the Company, filed August&nbsp;1, 2000(1).</FONT></TD>
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<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
4.2</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Form of common stock certificates(2).</FONT></TD>
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<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
4.3</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Investor Rights Agreements(3).</FONT></TD>
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<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
4.4</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Relevant portions of the Amended and Restated By-laws of the Company(4).</FONT></TD>
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<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
4.5</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
2001 Arena Employee Stock Purchase Plan.</FONT></TD>
</TR>
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<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
5.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Opinion of Morgan, Lewis &amp; Bockius, LLP, counsel to the Company, regarding legality.</FONT></TD>
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<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
23.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Consent of Ernst &amp; Young LLP, Independent Auditors.</FONT></TD>
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<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
23.2</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Consent of Counsel (included in Exhibit&nbsp;5.1).</FONT></TD>
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<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
24.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Power of Attorney (set forth on signature page to this Registration Statement).</FONT></TD>
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<DL compact>
<DT><FONT SIZE=2>(1)</FONT></DT><DD><FONT SIZE=2>Incorporated
herein by reference to Exhibit&nbsp;3.1 to the Company's Registration Statement on Form&nbsp;S-1, as amended, filed July&nbsp;25, 2000; Commission
File No.&nbsp;333-35944.
<BR><BR></FONT></DD><DT><FONT SIZE=2>(2)</FONT></DT><DD><FONT SIZE=2>Incorporated
herein by reference to Exhibit&nbsp;4.2 to the Company's Registration Statement on Form&nbsp;S-1, as amended, filed on July&nbsp;19, 2000; Commission
File No.&nbsp;333-35944.
<BR><BR></FONT></DD><DT><FONT SIZE=2>(3)</FONT></DT><DD><FONT SIZE=2>Incorporated
herein by reference to Exhibit&nbsp;4.3 to the Company's Registration Statement on Form&nbsp;S-1, as amended, filed July&nbsp;25, 2000; Commission
File No.&nbsp;333-35944.
<BR><BR></FONT></DD><DT><FONT SIZE=2>(4)</FONT></DT><DD><FONT SIZE=2>Incorporated
herein by reference to Exhibit&nbsp;3.2 to the Company's Registration Statement on Form&nbsp;S-1, as amended, filed July&nbsp;19, 2000; Commission
File No.&nbsp;333-35944. </FONT></DD></DL>

<P><FONT SIZE=2><A
NAME="de1519_item_9._undertakings."> </A>
<A NAME="toc_de1519_10"> </A>
<BR></FONT><FONT SIZE=2><B>Item 9. Undertakings.    <BR>  </B></FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;The undersigned registrant hereby undertakes: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;(1)
To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement: </FONT></P>

<UL>
<DL compact>
<DT><FONT SIZE=2>(i)</FONT></DT><DD><FONT SIZE=2>To
include any prospectus required by Section&nbsp;10(a)(3) of the Securities Act of 1933;
<BR><BR></FONT></DD><DT><FONT SIZE=2>(ii)</FONT></DT><DD><FONT SIZE=2>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&nbsp;424(b) if, in the aggregate, the changes in volume and price
represent no more than 20&nbsp;percent change in the maximum aggregate offering price set forth in the "Calculation of Registration Fee" table in the effective registration statement;
<BR><BR></FONT></DD><DT><FONT SIZE=2>(iii)</FONT></DT><DD><FONT SIZE=2>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></DD></DL>
</UL>
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<UL>

<P><FONT SIZE=2>Provided,
however, that paragraphs (a)(1)(i)&nbsp;and (a)(1)(ii)&nbsp;above do not apply if the information required to be included in a post-effective amendment by those paragraphs is
contained in periodic reports filed with or furnished to the Commission by the registrant pursuant to Section&nbsp;13 or Section&nbsp;15(d) of the Securities Exchange Act of 1934 that are
incorporated by reference in this registration statement. </FONT></P>

</UL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;(2)&nbsp;That,
for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;(3)&nbsp;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><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;The
undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant's
annual report pursuant to Section&nbsp;13(a) or Section&nbsp;15(d) of the Securities Exchange Act of 1934 that is incorporated by reference in the registration statement shall be deemed to be a
new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;Insofar
as indemnification for liabilities arising under the Securities Act of 1934 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 Commission such indemnification is against public policy as expressed in the
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 Act and will be governed by the final adjudication of such issue. </FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="jc1519_signatures"> </A>
<A NAME="toc_jc1519_1"> </A>
<BR></FONT><FONT SIZE=2><B>SIGNATURES    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Pursuant to the requirements of the Securities Act of 1933, 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;13, 2001. </FONT></P>

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<TD WIDTH="47%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD COLSPAN=3><FONT SIZE=2><B>ARENA PHARMACEUTICALS, INC.</B></FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="47%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="5%"><FONT SIZE=2><BR>
By:</FONT></TD>
<TD WIDTH="1%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="45%" ALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;</FONT><FONT SIZE=2>JACK LIEF</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Jack Lief<BR></FONT> <FONT SIZE=2><I>President and Chief Executive Officer</I></FONT></TD>
</TR>
</TABLE>
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<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="jc1519_power_of_attorney"> </A>
<A NAME="toc_jc1519_2"> </A>
<BR></FONT><FONT SIZE=2><B>POWER OF ATTORNEY    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;KNOW ALL PERSONS BY THESE PRESENTS, that each of the undersigned directors and officers of Arena Pharmaceuticals,&nbsp;Inc. hereby constitutes and appoints
Jack Lief and Richard P. Burgoon, Jr., and each of them, his true and lawful attorneys-in-fact and agents, for him and in his name, place and stead, in any and all capacities,
to sign one or more amendments to this Registration Statement on Form&nbsp;S-8 under the Securities Act, including post-effective amendments and other related documents, and
to file the same with the Commission under the Securities Act, hereby granting unto each such attorneys-in-fact and agents full power and authority to do and perform any and
all acts and things requisite and necessary to be done in and about the premises, as fully as to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that
said attorneys-in-fact and agents may lawfully do or cause to be done by virtue hereof </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Pursuant
to the requirements of the Securities Act of 1933, this Registration Statement and the foregoing Power of Attorney has been signed by the following persons in the capacities
indicated on the dates indicated: </FONT></P>

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<TH WIDTH="47%" ALIGN="CENTER"><FONT SIZE=1><B>Signature</B></FONT><HR NOSHADE></TH>
<TH WIDTH="3%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="29%" ALIGN="CENTER"><FONT SIZE=1><B>Title</B></FONT><HR NOSHADE></TH>
<TH WIDTH="3%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="19%" ALIGN="CENTER"><FONT SIZE=1><B>Date</B></FONT><HR NOSHADE></TH>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="47%" ALIGN="CENTER" VALIGN="CENTER"><BR><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="29%" VALIGN="CENTER"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="19%" VALIGN="CENTER"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="47%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2>/s/&nbsp;</FONT><FONT SIZE=2>JACK LIEF</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Jack Lief</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="29%" VALIGN="CENTER"><FONT SIZE=2>President, Chief Executive Officer and Director</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="19%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2>June 13, 2001</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="47%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;</FONT><FONT SIZE=2>DOMINIC P. BEHAN</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Dominic P. Behan</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="29%" VALIGN="CENTER"><FONT SIZE=2><BR>
Vice President, Research and Director</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="19%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
June 13, 2001</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="47%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;</FONT><FONT SIZE=2>DEREK T. CHALMERS</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Derek T. Chalmers</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="29%" VALIGN="CENTER"><FONT SIZE=2><BR>
Vice President, Research and Director</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="19%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
June 13, 2001</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="47%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;</FONT><FONT SIZE=2>ROBERT HOFFMAN</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Robert Hoffman</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="29%" VALIGN="CENTER"><FONT SIZE=2><BR>
Vice President, Finance (principal financial officer and principal accounting officer)</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="19%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
June 13, 2001</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="47%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;</FONT><FONT SIZE=2>JOHN P. MCALISTER, III</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> John P. McAlister, III</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="29%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="19%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
June 13, 2001</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="47%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;</FONT><FONT SIZE=2>MICHAEL STEINMETZ</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Michael Steinmetz</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="29%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="19%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
June 13, 2001</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="47%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
/s/&nbsp;</FONT><FONT SIZE=2>STEFAN RYSER</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Stefan Ryser</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="29%" VALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="3%" VALIGN="CENTER"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="19%" ALIGN="CENTER" VALIGN="CENTER"><FONT SIZE=2><BR>
June 13, 2001</FONT></TD>
</TR>
</TABLE>
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<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="ka1519_index_to_exhibits"> </A>
<A NAME="toc_ka1519_1"> </A>
<BR></FONT><FONT SIZE=2><B>INDEX TO EXHIBITS    <BR>  </B></FONT></P>

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<TR VALIGN="BOTTOM">
<TH WIDTH="8%" ALIGN="CENTER"><FONT SIZE=1><B>Exhibit No.</B></FONT><HR NOSHADE></TH>
<TH WIDTH="3%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="89%" ALIGN="CENTER"><FONT SIZE=1><B>Description</B></FONT><HR NOSHADE></TH>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2>4.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2>Relevant portions of the Fourth Amended and Restated Certificate of Incorporation of the Company, filed August&nbsp;1, 2000(1).</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
4.2</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Form of common stock certificates(2).</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
4.3</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Investor Rights Agreements(3).</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
4.4</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Relevant portions of the Amended and Restated By-laws of the Company(4).</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
4.5</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
2001 Arena Employee Stock Purchase Plan.</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
5.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Opinion of Morgan, Lewis &amp; Bockius, LLP, counsel to the Company, regarding legality.</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
23.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Consent of Ernst &amp; Young LLP, Independent Auditors.</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
23.2</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Consent of Counsel (included in Exhibit&nbsp;5.1).</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="8%" ALIGN="RIGHT"><FONT SIZE=2><BR>
24.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Power of Attorney (set forth on signature page to this Registration Statement).</FONT></TD>
</TR>
</TABLE>
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<HR NOSHADE ALIGN="LEFT" WIDTH="120">
<DL compact>
<DT><FONT SIZE=2>(1)</FONT></DT><DD><FONT SIZE=2>Incorporated
herein by reference to Exhibit&nbsp;3.1 to the Company's Registration Statement on Form&nbsp;S-1, as amended, filed July&nbsp;25, 2000; Commission
File No.&nbsp;333-35944.
<BR><BR></FONT></DD><DT><FONT SIZE=2>(2)</FONT></DT><DD><FONT SIZE=2>Incorporated
herein by reference to Exhibit&nbsp;4.2 to the Company's Registration Statement on Form&nbsp;S-1, as amended, filed on July&nbsp;19, 2000; Commission
File No.&nbsp;333-35944.
<BR><BR></FONT></DD><DT><FONT SIZE=2>(3)</FONT></DT><DD><FONT SIZE=2>Incorporated
herein by reference to Exhibit&nbsp;4.3 to the Company's Registration Statement on Form&nbsp;S-1, as amended, filed July&nbsp;25, 2000; Commission
File No.&nbsp;333-35944.
<BR><BR></FONT></DD><DT><FONT SIZE=2>(4)</FONT></DT><DD><FONT SIZE=2>Incorporated
herein by reference to Exhibit&nbsp;3.2 to the Company's Registration Statement on Form&nbsp;S-1, as amended, filed July&nbsp;19, 2000; Commission
File No.&nbsp;333-35944. </FONT></DD></DL>
<HR NOSHADE>
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<BR>
<P><br><A NAME="01SAN1519_1">QuickLinks</A><br></P><!-- TOC_BEGIN -->
<FONT SIZE=2><A HREF="#toc_de1519_1">PART I</A></FONT><BR>
<UL>
<FONT SIZE=2><A HREF="#toc_de1519_2">Item 1. Plan Information</A></FONT><BR>
</UL>
<FONT SIZE=2><A HREF="#toc_de1519_3">PART II</A></FONT><BR>
<UL>
<FONT SIZE=2><A HREF="#toc_de1519_4">Item 3. Incorporation of Documents by Reference.</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_de1519_5">Item 4. Description of Securities.</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_de1519_6">Item 5. Interests of Named Experts and Counsel.</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_de1519_7">Item 6. Indemnification of Directors and Officers.</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_de1519_8">Item 7. Exemption from Registration Claimed.</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_de1519_9">Item 8. Exhibits.</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_de1519_10">Item 9. Undertakings.</A></FONT><BR>
</UL>
<!-- TOC_BEGIN -->
<FONT SIZE=2><A HREF="#toc_jc1519_1">SIGNATURES</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_jc1519_2">POWER OF ATTORNEY</A></FONT><BR>
<!-- TOC_BEGIN -->
<FONT SIZE=2><A HREF="#toc_ka1519_1">INDEX TO EXHIBITS</A></FONT><BR>
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[{"type": "S-8", "sequence": "1", "filename": "a2051805zs-8.htm", "description": "FORM S-8", "secsgml_size_bytes": 38438}]
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Prepared by MERRILL CORPORATION
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SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 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
(State or other jurisdiction
of incorporation or organization)
23-2908305
(I.R.S. Employer Identification No.)
6166 Nancy Ridge Drive
San Diego, CA
(Address of principal executive offices)
92121
(Zip Code)
2001 ARENA EMPLOYEE STOCK PURCHASE PLAN
(Full title of the plan)
Jack Lief
Arena Pharmaceuticals, Inc.
6166 Nancy Ridge Drive
San Diego, CA 92121
(Name and address of agent for service)
(858) 453-7200
(Telephone number, including area code, of agent for service)
Copies of all communications to:
General Counsel
Arena Pharmaceuticals, Inc.
6166 Nancy Ridge Drive
San Diego, CA 92121
(858) 453-7200
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(3)
Common Stock, par value $0.0001 per share
1,000,000 shares
$25.905
$25,905,000
$6,476.25
(1)
This
Registration Statement shall cover shares of Common Stock of Arena Pharmaceuticals which are offered or sold pursuant to the plan named above. Pursuant to Rule 416(a) of
the Securities Act of 1933, this registration statement shall also cover any additional shares of Common Stock which are offered or issued under the plan to prevent dilution resulting from stock
splits, stock dividends or similar transactions.
(2)
Estimated
pursuant to paragraphs (c) and (h) of Rule 457 solely for the purpose of calculating the registration fee, based upon the average of the reported high
and low sales prices for a share of Common Stock of Arena Pharmaceuticals, Inc. on June 6, 2001 as reported in the Nasdaq National Market.
(3)
Calculated
pursuant to Section 6(b) of the Securities Act of 1933 as follows: proposed maximum aggregated offering price multiplied by $250.00/$1,000,000.
PART I
INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS
Item 1. Plan Information
The documents containing the information specified in Part I of this Registration Statement will be sent or given to employees as specified by
Rule 428(b)(1) of the Securities Act of 1933, as amended (the "Securities Act"). Such documents are not required to be and are not filed with the Securities and Exchange Commission (the
"Commission") either as part of this Registration Statement or as prospectuses or prospectus supplements pursuant to Rule 424. These documents and the documents incorporated by reference in
this Registration Statement pursuant to Item 3 of Part II of this Form S-8, taken together, constitute a prospectus that meets the requirements of Section 10(a) of the
Securities Act.
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") with the Commission, are incorporated by reference into this Registration
Statement:
1.
The
Company's latest annual report on Form 10-K for the fiscal year ended December 31, 2000 filed pursuant to Section 13(a) or 15(d) of the
Securities and Exchange Act of 1934 (the "Exchange Act");
2.
All
other reports the Company has filed pursuant to Sections 13(a) or 15(d) of the Exchange Act since the end of the fiscal year coved by the document referred to in
(1) above; and
3.
The
description of the shares of the Company's Common Stock contained in the Company's Registration Statement on Form 8-A (File No. 333-35944)
filed under the Exchange Act with the Commission on July 26, 2000, which incorporates by reference the sections entitled "Prospectus Summary" and "Description of Capital Stock" in the
prospectus contained in the Registration Statement on Form S-1, filed July 26, 2000, including all amendments and reports updating such description (File
No. 333-35944).
All
documents subsequently filed by the Company with the Commission pursuant to Sections 13(a), 13(c), 14 and 15(d) of the Exchange Act after the date of this Registration Statement,
but prior to the filing of a post-effective amendment to this Registration Statement which indicates that all securities offered by this Registration Statement have been sold or which
deregisters all such securities then remaining unsold, shall be deemed to be incorporated by reference into this Registration Statement. Each document incorporated by reference into this Registration
Statement shall be deemed to be a part of this Registration Statement from the date of the filing of such document with the Commission until the information contained therein is superseded or updated
by any subsequently filed document which is incorporated by reference into this Registration Statement or by any document which constitutes part of the prospectus relating to the 2001 Arena Employee
Stock Purchase Plan and meets the requirements of Section 10(a) of the Securities Act.
Any
statement contained in a document incorporated by reference herein shall be deemed to be modified or superseded for purposes hereof to the extent that a statement contained herein
(or in any other subsequently filed document that is also incorporated by reference herein) modifies or supersedes such statement. Any such statement so modified or superseded shall not be deemed,
except as so modified or superseded, to constitute a part hereof.
Item 4. Description of Securities.
Not Applicable.
Item 5. Interests of Named Experts and Counsel.
Not Applicable.
Item 6. Indemnification of Directors and Officers.
Section 145 of the General Corporation Law of the State of Delaware (the "DGCL") permits a corporation, under specified circumstances, to
indemnify its directors, officers, employees or agents against expenses (including attorney's fees), judgments, fines and amounts paid in settlements actually and reasonably incurred by them in
connection with any action, suit or proceeding brought by third parties by reason of the fact that they were or are directors, officers, employees or agents of the corporation or were or are serving
at the request of the corporation as a director, officer, employee or agent of another corporation, if such directors, officers, employees, or agents acted in good faith and in a manner they
reasonably believed to be in or not opposed to the best interests of the corporation and, with respect to any criminal action or proceeding, had no reasonable cause to believe their conduct was
unlawful. In a derivative action, i.e., one by or in the right of the corporation, indemnification may be made only for expenses actually and reasonably incurred by directors, officers, employees or
agents in connection with the defense or settlement of an action or suit, and only with respect to a matter as to which they shall have acted in good faith and in a manner they reasonably believed to
be in or not opposed to the best interests of the corporation, except that no indemnification shall be made in respect of any claim, issue or matter as to which such person shall be adjudicated to be
liable to the corporation unless the court in which the action or suit was brought shall determine upon application that the defendant directors, officers, employees, or agents are fairly and
reasonably entitled to indemnification for such expenses in view of all of the circumstances of the case, despite such adjudication of liability. Expenses incurred (including attorney's fees) by an
officer or director in defending any civil, criminal, administrative or investigative action, suit or proceeding may be paid by the corporation in advance of the final disposition of such action, suit
or proceeding upon receipt of an undertaking by or on behalf of such director or officer to repay such amount if it shall ultimately be determined that he is not entitled to be indemnified by the
corporation.
Article V
of the Company's Fourth Restated and Amended Certificate of Incorporation, provides that a director shall not be personally liable to the Company or its stockholders
for monetary damages for breach of fiduciary duty as a director, except for liability (a) for any breach of the director's duty of loyalty to the Company or its stockholders, (b) for
acts or omissions not in good faith or which involve intentional misconduct or a knowing violation of law, (c) pursuant to Section 174 of the DGCL, or (d) for any transaction from
which a director derived an improper personal benefit.
Article IV
of the Company's by-laws provides that it shall, to the full extent authorized or permitted by applicable law, indemnify any current or former director
or officer. Subject to applicable law, the Company may indemnify an employee or agent to the extent that the board of directors or stockholders may determine in its or their discretion.
The
Company maintains an insurance policy containing customary terms and conditions for the purpose of insuring its directors and officers against certain losses incurred by them as a
result of claims based upon their actions or statements (including omissions to act or make statements) as directors and officers which may cover liabilities under the Securities Act.
Item 7. Exemption from Registration Claimed.
Not Applicable.
Item 8. Exhibits.
The following exhibits are filed herewith or incorporated by reference as part of this Registration Statement:
Exhibit No.
Description
4.1
Relevant portions of the Fourth Amended and Restated Certificate of Incorporation of the Company, filed August 1, 2000(1).
4.2
Form of common stock certificates(2).
4.3
Investor Rights Agreements(3).
4.4
Relevant portions of the Amended and Restated By-laws of the Company(4).
4.5
2001 Arena Employee Stock Purchase Plan.
5.1
Opinion of Morgan, Lewis & Bockius, LLP, counsel to the Company, regarding legality.
23.1
Consent of Ernst & Young LLP, Independent Auditors.
23.2
Consent of Counsel (included in Exhibit 5.1).
24.1
Power of Attorney (set forth on signature page to this Registration Statement).
(1)
Incorporated
herein by reference to Exhibit 3.1 to the Company's Registration Statement on Form S-1, as amended, filed July 25, 2000; Commission
File No. 333-35944.
(2)
Incorporated
herein by reference to Exhibit 4.2 to the Company's Registration Statement on Form S-1, as amended, filed on July 19, 2000; Commission
File No. 333-35944.
(3)
Incorporated
herein by reference to Exhibit 4.3 to the Company's Registration Statement on Form S-1, as amended, filed July 25, 2000; Commission
File No. 333-35944.
(4)
Incorporated
herein by reference to Exhibit 3.2 to the Company's Registration Statement on Form S-1, as amended, filed July 19, 2000; Commission
File No. 333-35944.
Item 9. Undertakings.
The undersigned registrant hereby undertakes:
(a) (1)
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 of 1933;
(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 20 percent 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)(1)(i) and (a)(1)(ii) above do not apply if the information required to be included in a post-effective amendment by those paragraphs is
contained in periodic reports filed with or furnished to the Commission by the registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are
incorporated by reference in this registration statement.
(2) That,
for the purpose of determining any liability under the Securities Act of 1933, each such post-effective amendment shall be deemed to be a new
registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.
(3) 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) The
undersigned registrant hereby undertakes that, for purposes of determining any liability under the Securities Act of 1933, each filing of the registrant's
annual report pursuant to Section 13(a) or Section 15(d) of the Securities Exchange Act of 1934 that is incorporated by reference in the registration statement shall be deemed to be a
new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initial bona fide offering thereof.
(c) Insofar
as indemnification for liabilities arising under the Securities Act of 1934 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 Commission such indemnification is against public policy as expressed in the
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 Act and will be governed by the final adjudication of such issue.
SIGNATURES
Pursuant to the requirements of the Securities Act of 1933, 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 13, 2001.
ARENA PHARMACEUTICALS, INC.
By:
/s/
JACK LIEF
Jack Lief
President and Chief Executive Officer
POWER OF ATTORNEY
KNOW ALL PERSONS BY THESE PRESENTS, that each of the undersigned directors and officers of Arena Pharmaceuticals, Inc. hereby constitutes and appoints
Jack Lief and Richard P. Burgoon, Jr., and each of them, his true and lawful attorneys-in-fact and agents, for him and in his name, place and stead, in any and all capacities,
to sign one or more amendments to this Registration Statement on Form S-8 under the Securities Act, including post-effective amendments and other related documents, and
to file the same with the Commission under the Securities Act, hereby granting unto each such attorneys-in-fact and agents full power and authority to do and perform any and
all acts and things requisite and necessary to be done in and about the premises, as fully as to all intents and purposes as he might or could do in person, hereby ratifying and confirming all that
said attorneys-in-fact and agents may lawfully do or cause to be done by virtue hereof
Pursuant
to the requirements of the Securities Act of 1933, this Registration Statement and the foregoing Power of Attorney has been signed by the following persons in the capacities
indicated on the dates indicated:
Signature
Title
Date
/s/
JACK LIEF
Jack Lief
President, Chief Executive Officer and Director
June 13, 2001
/s/
DOMINIC P. BEHAN
Dominic P. Behan
Vice President, Research and Director
June 13, 2001
/s/
DEREK T. CHALMERS
Derek T. Chalmers
Vice President, Research and Director
June 13, 2001
/s/
ROBERT HOFFMAN
Robert Hoffman
Vice President, Finance (principal financial officer and principal accounting officer)
June 13, 2001
/s/
JOHN P. MCALISTER, III
John P. McAlister, III
Director
June 13, 2001
/s/
MICHAEL STEINMETZ
Michael Steinmetz
Director
June 13, 2001
/s/
STEFAN RYSER
Stefan Ryser
Director
June 13, 2001
INDEX TO EXHIBITS
Exhibit No.
Description
4.1
Relevant portions of the Fourth Amended and Restated Certificate of Incorporation of the Company, filed August 1, 2000(1).
4.2
Form of common stock certificates(2).
4.3
Investor Rights Agreements(3).
4.4
Relevant portions of the Amended and Restated By-laws of the Company(4).
4.5
2001 Arena Employee Stock Purchase Plan.
5.1
Opinion of Morgan, Lewis & Bockius, LLP, counsel to the Company, regarding legality.
23.1
Consent of Ernst & Young LLP, Independent Auditors.
23.2
Consent of Counsel (included in Exhibit 5.1).
24.1
Power of Attorney (set forth on signature page to this Registration Statement).
(1)
Incorporated
herein by reference to Exhibit 3.1 to the Company's Registration Statement on Form S-1, as amended, filed July 25, 2000; Commission
File No. 333-35944.
(2)
Incorporated
herein by reference to Exhibit 4.2 to the Company's Registration Statement on Form S-1, as amended, filed on July 19, 2000; Commission
File No. 333-35944.
(3)
Incorporated
herein by reference to Exhibit 4.3 to the Company's Registration Statement on Form S-1, as amended, filed July 25, 2000; Commission
File No. 333-35944.
(4)
Incorporated
herein by reference to Exhibit 3.2 to the Company's Registration Statement on Form S-1, as amended, filed July 19, 2000; Commission
File No. 333-35944.
QuickLinks
PART I
Item 1. Plan Information
PART II
Item 3. Incorporation of Documents by Reference.
Item 4. Description of Securities.
Item 5. Interests of Named Experts and Counsel.
Item 6. Indemnification of Directors and Officers.
Item 7. Exemption from Registration Claimed.
Item 8. Exhibits.
Item 9. Undertakings.
SIGNATURES
POWER OF ATTORNEY
INDEX TO EXHIBITS