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<P ALIGN="CENTER"><FONT SIZE=2><B> As filed with the Securities and Exchange Commission on&nbsp;July&nbsp;22, 2002  </B></FONT></P>

<P ALIGN="RIGHT"><FONT 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 ALIGN="CENTER"><FONT SIZE=5><B>SECURITIES AND EXCHANGE COMMISSION<BR>  </B></FONT><FONT SIZE=2><B>Washington, D.C. 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>ONYX 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</B></FONT><FONT SIZE=2><BR>
(State of incorporation)</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="49%" ALIGN="CENTER"><FONT SIZE=2><B>94-3154463</B></FONT><FONT SIZE=2><BR>
(I.R.S. Employer Identification No.)</FONT></TD>
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<P ALIGN="CENTER"><FONT SIZE=2><B>3031 Research Drive<BR>
Richmond, California 94806<BR>
(510)&nbsp;222-9700<BR>  </B></FONT><FONT SIZE=2>(Address and telephone number of Principal Executive Offices) </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B>1996 EQUITY INCENTIVE PLAN<BR>
1996 EMPLOYEE STOCK PURCHASE PLAN<BR>  </B></FONT><FONT SIZE=2>(Full title of the plan) </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B>Hollings C. Renton<BR>
Chairman of the Board, President and Chief Executive Officer<BR>
Onyx Pharmaceuticals,&nbsp;Inc.<BR>
3031 Research Drive<BR>
Richmond, California 94806<BR>
(510)&nbsp;222-9700<BR>  </B></FONT><FONT SIZE=2>(Name, address, and telephone number of agent for service) </FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=2>Copies
to:<BR></FONT> <FONT SIZE=2><B>Robert L. Jones, Esq.<BR>
Michael L. Weiner, Esq.<BR>
Cooley Godward LLP<BR>
Five Palo Alto Square<BR>
3000 El Camino Real<BR>
Palo Alto, California 94306-2155<BR>
(650)&nbsp;843-5000  </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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<TH WIDTH="31%" ALIGN="CENTER"><FONT SIZE=1><B>Title Of Securities To<BR>
Be Registered</B></FONT><BR></TH>
<TH WIDTH="2%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="13%" ALIGN="CENTER"><FONT SIZE=1><B>Amount To Be<BR>
Registered</B></FONT><BR></TH>
<TH WIDTH="2%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="17%" ALIGN="CENTER"><FONT SIZE=1><B>Proposed Maximum<BR>
Offering Price Per<BR>
Share(1)</B></FONT><BR></TH>
<TH WIDTH="2%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="17%" ALIGN="CENTER"><FONT SIZE=1><B>Proposed Maximum<BR>
Aggregate Offering<BR>
Price(1)</B></FONT><BR></TH>
<TH WIDTH="2%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="14%" ALIGN="CENTER"><FONT SIZE=1><B>Amount Of<BR>
Registration Fee</B></FONT><BR></TH>
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<TD WIDTH="31%" VALIGN="TOP"><FONT SIZE=2>Stock options and common stock (par value $.001)</FONT></TD>
<TD WIDTH="2%" VALIGN="TOP"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="13%" ALIGN="CENTER"><FONT SIZE=2>475,000</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="17%" ALIGN="CENTER"><FONT SIZE=2>$4.165</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="17%" ALIGN="CENTER"><FONT SIZE=2>$1,978,375</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="14%" ALIGN="CENTER"><FONT SIZE=2>$183</FONT></TD>
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<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(1)</FONT></DT><DD><FONT SIZE=2>Estimated
solely for the purpose of calculating the amount of the registration fee pursuant to Rule&nbsp;457(h) of the Securities Act of 1933, as amended. The offering price per
share and aggregate offering price are based on the average of the high and low prices of the Registrant's Common Stock as reported on the Nasdaq National Market on July&nbsp;19, 2002. </FONT></DD></DL>
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NAME="page_ja1939_1_1"> </A> </FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="ja1939_part_ii"> </A>
<A NAME="toc_ja1939_1"> </A>
<BR></FONT><FONT SIZE=2><B>PART II    <BR>  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="ja1939_explanatory_note"> </A>
<A NAME="toc_ja1939_2"> </A>
<BR></FONT><FONT SIZE=2><B>EXPLANATORY NOTE    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;This Registration Statement on Form&nbsp;S-8 is being filed for the purpose of registering an additional 400,000 shares of Onyx
Pharmaceuticals,&nbsp;Inc. (the "Company") Common Stock to be issued pursuant to the Company's 1996 Equity Incentive Plan, as amended, and 75,000 shares of the Company's Common Stock to be issued
pursuant to the Company's Employee Stock Purchase Plan, as amended. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="ja1939_incorporation_of_certain_documents_by_reference"> </A>
<A NAME="toc_ja1939_3"> </A>
<BR></FONT><FONT SIZE=2><B>INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The following documents filed by Onyx Pharmaceuticals,&nbsp;Inc. with the Securities and Exchange Commission are incorporated by reference into this
Registration Statement: </FONT></P>

<UL>
<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>a)</FONT></DT><DD><FONT SIZE=2>The
Company's Annual Report on Form&nbsp;10-K for the fiscal year ended December&nbsp;31, 2001;
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>b)</FONT></DT><DD><FONT SIZE=2>The
Company's Quarterly Report on Form&nbsp;10-Q for the quarter ended March&nbsp;31, 2002.
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>c)</FONT></DT><DD><FONT SIZE=2>The
Company's Registration Statement on Form&nbsp;S-8 filed on May&nbsp;30, 1996, under the Securities Act of 1933, as amended (file No.&nbsp;333-04839);
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>d)</FONT></DT><DD><FONT SIZE=2>The
Company's Registration Statement on Form&nbsp;S-8 filed on August&nbsp;29, 1997, under the Securities Act of 1933, as amended (file
No.&nbsp;333-34681);
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>e)</FONT></DT><DD><FONT SIZE=2>The
Company's Registration Statement on Form&nbsp;S-8 filed on August&nbsp;6, 1998, under the Securities Act of 1933, as amended (file
No.&nbsp;333-60805);
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>f)</FONT></DT><DD><FONT SIZE=2>The
Company's Registration Statement on Form&nbsp;S-8 filed on July&nbsp;30, 1999, under the Securities Act of 1933, as amended (file No.&nbsp;333-84113);
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>g)</FONT></DT><DD><FONT SIZE=2>The
Company's Registration Statement on Form&nbsp;S-8 filed on October&nbsp;18, 2000, under the Securities Act of 1933, as amended (file
No.&nbsp;333-48146);
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>h)</FONT></DT><DD><FONT SIZE=2>The
Company's Registration Statement on Form&nbsp;S-8 filed on July&nbsp;6, 2001, under the Securities Act of 1933, as amended (file No.&nbsp;333-64706). </FONT></DD></DL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;All
reports and other documents subsequently filed by the Company pursuant to Sections 13(a), 13(c), 14 and 15(d) of 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 herein and to be a part
of this registration statement from the date of the filing of such reports and documents. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>II-1</FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="ja1939_exhibits"> </A>
<A NAME="toc_ja1939_4"> </A>
<BR></FONT><FONT SIZE=2><B>EXHIBITS    <BR>  </B></FONT></P>

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<TH WIDTH="10%" ALIGN="LEFT"><FONT SIZE=1><B>Exhibit<BR>
Number<BR> </B></FONT><HR NOSHADE></TH>
<TH WIDTH="3%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="88%" ALIGN="LEFT"><FONT SIZE=1>&nbsp;</FONT><BR></TH>
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<TD WIDTH="10%"><FONT SIZE=2>5.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="88%"><FONT SIZE=2>Opinion of Cooley Godward LLP.</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="10%"><FONT SIZE=2><BR>
23.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="88%"><FONT SIZE=2><BR>
Consent of Ernst &amp; Young LLP, Independent Auditors.</FONT></TD>
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<TD WIDTH="10%"><FONT SIZE=2><BR>
23.2</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
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Consent of Cooley Godward LLP. Reference is made to Exhibit 5.1.</FONT></TD>
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<TD WIDTH="10%"><FONT SIZE=2><BR>
24.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="88%"><FONT SIZE=2><BR>
Power of Attorney. Reference is made to the signature pages.</FONT></TD>
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<TD WIDTH="10%"><FONT SIZE=2><BR>
99.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="88%"><FONT SIZE=2><BR>
1996 Equity Incentive Plan.</FONT></TD>
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<TD WIDTH="10%"><FONT SIZE=2><BR>
99.2</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="88%"><FONT SIZE=2><BR>
1996 Employee Stock Purchase Plan</FONT></TD>
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<P ALIGN="CENTER"><FONT SIZE=2>II-2</FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="jc1939_signatures"> </A>
<A NAME="toc_jc1939_1"> </A>
<BR></FONT><FONT SIZE=2><B>SIGNATURES    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;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
Richmond, State of California, on the 22<SUP>nd</SUP> day of July, 2002. </FONT></P>

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<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD COLSPAN=2><FONT SIZE=2><B>ONYX PHARMACEUTICALS,&nbsp;INC.</B></FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="52%"><FONT SIZE=2><B><BR>
&nbsp;</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%"><BR><FONT SIZE=2>By:</FONT></TD>
<TD WIDTH="40%"><FONT SIZE=2><BR>
/s/ Hollings C. Renton</FONT><HR NOSHADE><FONT SIZE=2><B>Hollings C. Renton</B></FONT><FONT SIZE=2><BR>
Chairman of the Board, President and Chief Executive Officer</FONT></TD>
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<P ALIGN="CENTER"><FONT SIZE=2>II-3</FONT></P>

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<A NAME="page_jc1939_1_4"> </A>
<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="jc1939_power_of_attorney"> </A>
<A NAME="toc_jc1939_2"> </A>
<BR></FONT><FONT SIZE=2><B>POWER OF ATTORNEY    <BR>  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Hollings C. Renton and Marilyn E. Wortzman, and each
or any one of them, his true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for him and in his 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 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><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;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>

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<TH WIDTH="39%" ALIGN="CENTER"><FONT SIZE=1><B>Signature</B></FONT><HR NOSHADE></TH>
<TH WIDTH="2%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="39%" ALIGN="CENTER"><FONT SIZE=1><B>Title</B></FONT><HR NOSHADE></TH>
<TH WIDTH="2%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="17%" ALIGN="CENTER"><FONT SIZE=1><B>Date</B></FONT><HR NOSHADE></TH>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="39%" VALIGN="TOP"><BR><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="TOP"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="39%" VALIGN="TOP"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="2%" VALIGN="TOP"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="17%" VALIGN="TOP"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2>/s/ Hollings C. Renton</FONT><HR NOSHADE><FONT SIZE=2> Hollings C. Renton</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="39%" ALIGN="CENTER"><FONT SIZE=2>Chairman of the Board, President and Chief Executive Officer </FONT><FONT SIZE=2><I>(Principal Executive and Financial Officer)</I></FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="17%" ALIGN="CENTER"><FONT SIZE=2>July 22, 2002</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2><BR>
/s/ Marilyn E. Wortzman</FONT><HR NOSHADE><FONT SIZE=2> Marilyn E. Wortzman</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="39%" ALIGN="CENTER"><FONT SIZE=2><BR>
Controller </FONT><FONT SIZE=2><I>(Principal Accounting Officer)</I></FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="17%" ALIGN="CENTER"><FONT SIZE=2><BR>
July 22, 2002</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="39%" VALIGN="TOP"><FONT SIZE=2><BR>
/s/ Wolf-Dieter Busse, Ph.D.</FONT><HR NOSHADE><FONT SIZE=2> Wolf-Dieter Busse, Ph.D.</FONT></TD>
<TD WIDTH="2%" VALIGN="TOP"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="39%" ALIGN="CENTER" VALIGN="TOP"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="2%" VALIGN="TOP"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="17%" ALIGN="CENTER" VALIGN="TOP"><FONT SIZE=2><BR>
July 22, 2002</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="39%" VALIGN="TOP"><FONT SIZE=2><BR>
/s/ Paul Goddard, Ph.D.</FONT><HR NOSHADE><FONT SIZE=2> Paul Goddard, Ph.D.</FONT></TD>
<TD WIDTH="2%" VALIGN="TOP"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="39%" ALIGN="CENTER" VALIGN="TOP"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="2%" VALIGN="TOP"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="17%" ALIGN="CENTER" VALIGN="TOP"><FONT SIZE=2><BR>
July 22, 2002</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2><BR>
&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Magnus Lundberg</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="39%" ALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="17%" ALIGN="CENTER"><FONT SIZE=2><BR>
July&nbsp;&nbsp;&nbsp;&nbsp;, 2002</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2><BR>
&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> George A. Scangos, Ph.D.</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="39%" ALIGN="CENTER"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="2%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="17%" ALIGN="CENTER"><FONT SIZE=2><BR>
July&nbsp;&nbsp;&nbsp;&nbsp;, 2002</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="39%" VALIGN="TOP"><FONT SIZE=2><BR>
/s/ Nicole Vitullo</FONT><HR NOSHADE><FONT SIZE=2> Nicole Vitullo</FONT></TD>
<TD WIDTH="2%" VALIGN="TOP"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="39%" ALIGN="CENTER" VALIGN="TOP"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="2%" VALIGN="TOP"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="17%" ALIGN="CENTER" VALIGN="TOP"><FONT SIZE=2><BR>
July 22, 2002</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD WIDTH="39%" VALIGN="TOP"><FONT SIZE=2><BR>
/s/ Wendell Wierenga, Ph.D.</FONT><HR NOSHADE><FONT SIZE=2> Wendell Wierenga, Ph.D.</FONT></TD>
<TD WIDTH="2%" VALIGN="TOP"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="39%" ALIGN="CENTER" VALIGN="TOP"><FONT SIZE=2><BR>
Director</FONT></TD>
<TD WIDTH="2%" VALIGN="TOP"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="17%" ALIGN="CENTER" VALIGN="TOP"><FONT SIZE=2><BR>
July 22, 2002</FONT></TD>
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<P ALIGN="CENTER"><FONT SIZE=2>II-4</FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="ka1939_exhibit_index"> </A>
<A NAME="toc_ka1939_1"> </A>
<BR></FONT><FONT SIZE=2><B>EXHIBIT INDEX    <BR>  </B></FONT></P>

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<TH WIDTH="9%" ALIGN="LEFT"><FONT SIZE=1><B>Exhibit No.<BR> </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>
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<TD WIDTH="9%"><FONT SIZE=2>5.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2>Opinion of Cooley Godward LLP.</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="9%"><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>
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<TD WIDTH="9%"><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 Cooley Godward LLP. Reference is made to Exhibit 5.1.</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="9%"><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. Reference is made to the signature pages.</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="9%"><FONT SIZE=2><BR>
99.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
1996 Equity Incentive Plan.</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="9%"><FONT SIZE=2><BR>
99.2</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
1996 Employee Stock Purchase Plan.</FONT></TD>
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<P><br><A NAME="02PAL1939_1">QuickLinks</A><br></P><!-- TOC_BEGIN -->
<FONT SIZE=2><A HREF="#toc_ja1939_1">PART II</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_ja1939_2">EXPLANATORY NOTE</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_ja1939_3">INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_ja1939_4">EXHIBITS</A></FONT><BR>
<!-- TOC_BEGIN -->
<FONT SIZE=2><A HREF="#toc_jc1939_1">SIGNATURES</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_jc1939_2">POWER OF ATTORNEY</A></FONT><BR>
<!-- TOC_BEGIN -->
<FONT SIZE=2><A HREF="#toc_ka1939_1">EXHIBIT INDEX</A></FONT><BR>
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As filed with the Securities and Exchange Commission on July 22, 2002
Registration No. 333-
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM S-8
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933
ONYX PHARMACEUTICALS, INC.
(Exact name of registrant as specified in its charter)
Delaware
(State of incorporation)
94-3154463
(I.R.S. Employer Identification No.)
3031 Research Drive
Richmond, California 94806
(510) 222-9700
(Address and telephone number of Principal Executive Offices)
1996 EQUITY INCENTIVE PLAN
1996 EMPLOYEE STOCK PURCHASE PLAN
(Full title of the plan)
Hollings C. Renton
Chairman of the Board, President and Chief Executive Officer
Onyx Pharmaceuticals, Inc.
3031 Research Drive
Richmond, California 94806
(510) 222-9700
(Name, address, and telephone number of agent for service)
Copies
to:
Robert L. Jones, Esq.
Michael L. Weiner, Esq.
Cooley Godward LLP
Five Palo Alto Square
3000 El Camino Real
Palo Alto, California 94306-2155
(650) 843-5000
CALCULATION OF REGISTRATION FEE
Title Of Securities To
Be Registered
Amount To Be
Registered
Proposed Maximum
Offering Price Per
Share(1)
Proposed Maximum
Aggregate Offering
Price(1)
Amount Of
Registration Fee
Stock options and common stock (par value $.001)
475,000
$4.165
$1,978,375
$183
(1)
Estimated
solely for the purpose of calculating the amount of the registration fee pursuant to Rule 457(h) of the Securities Act of 1933, as amended. The offering price per
share and aggregate offering price are based on the average of the high and low prices of the Registrant's Common Stock as reported on the Nasdaq National Market on July 19, 2002.
PART II
EXPLANATORY NOTE
This Registration Statement on Form S-8 is being filed for the purpose of registering an additional 400,000 shares of Onyx
Pharmaceuticals, Inc. (the "Company") Common Stock to be issued pursuant to the Company's 1996 Equity Incentive Plan, as amended, and 75,000 shares of the Company's Common Stock to be issued
pursuant to the Company's Employee Stock Purchase Plan, as amended.
INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE
The following documents filed by Onyx Pharmaceuticals, Inc. with the Securities and Exchange Commission are incorporated by reference into this
Registration Statement:
a)
The
Company's Annual Report on Form 10-K for the fiscal year ended December 31, 2001;
b)
The
Company's Quarterly Report on Form 10-Q for the quarter ended March 31, 2002.
c)
The
Company's Registration Statement on Form S-8 filed on May 30, 1996, under the Securities Act of 1933, as amended (file No. 333-04839);
d)
The
Company's Registration Statement on Form S-8 filed on August 29, 1997, under the Securities Act of 1933, as amended (file
No. 333-34681);
e)
The
Company's Registration Statement on Form S-8 filed on August 6, 1998, under the Securities Act of 1933, as amended (file
No. 333-60805);
f)
The
Company's Registration Statement on Form S-8 filed on July 30, 1999, under the Securities Act of 1933, as amended (file No. 333-84113);
g)
The
Company's Registration Statement on Form S-8 filed on October 18, 2000, under the Securities Act of 1933, as amended (file
No. 333-48146);
h)
The
Company's Registration Statement on Form S-8 filed on July 6, 2001, under the Securities Act of 1933, as amended (file No. 333-64706).
All
reports and other documents subsequently filed by the Company pursuant to Sections 13(a), 13(c), 14 and 15(d) of 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 herein and to be a part
of this registration statement from the date of the filing of such reports and documents.
II-1
EXHIBITS
Exhibit
Number
5.1
Opinion of Cooley Godward LLP.
23.1
Consent of Ernst & Young LLP, Independent Auditors.
23.2
Consent of Cooley Godward LLP. Reference is made to Exhibit 5.1.
24.1
Power of Attorney. Reference is made to the signature pages.
99.1
1996 Equity Incentive Plan.
99.2
1996 Employee Stock Purchase Plan
II-2
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
Richmond, State of California, on the 22
nd
day of July, 2002.
ONYX PHARMACEUTICALS, INC.
By:
/s/ Hollings C. Renton
Hollings C. Renton
Chairman of the Board, President and Chief Executive Officer
II-3
POWER OF ATTORNEY
KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature appears below constitutes and appoints Hollings C. Renton and Marilyn E. Wortzman, and each
or any one of them, his true and lawful attorney-in-fact and agent, with full power of substitution and resubstitution, for him and in his 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 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
Title
Date
/s/ Hollings C. Renton
Hollings C. Renton
Chairman of the Board, President and Chief Executive Officer
(Principal Executive and Financial Officer)
July 22, 2002
/s/ Marilyn E. Wortzman
Marilyn E. Wortzman
Controller
(Principal Accounting Officer)
July 22, 2002
/s/ Wolf-Dieter Busse, Ph.D.
Wolf-Dieter Busse, Ph.D.
Director
July 22, 2002
/s/ Paul Goddard, Ph.D.
Paul Goddard, Ph.D.
Director
July 22, 2002
Magnus Lundberg
Director
July    , 2002
George A. Scangos, Ph.D.
Director
July    , 2002
/s/ Nicole Vitullo
Nicole Vitullo
Director
July 22, 2002
/s/ Wendell Wierenga, Ph.D.
Wendell Wierenga, Ph.D.
Director
July 22, 2002
II-4
EXHIBIT INDEX
Exhibit No.
Description
5.1
Opinion of Cooley Godward LLP.
23.1
Consent of Ernst & Young LLP, Independent Auditors.
23.2
Consent of Cooley Godward LLP. Reference is made to Exhibit 5.1.
24.1
Power of Attorney. Reference is made to the signature pages.
99.1
1996 Equity Incentive Plan.
99.2
1996 Employee Stock Purchase Plan.
QuickLinks
PART II
EXPLANATORY NOTE
INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE
EXHIBITS
SIGNATURES
POWER OF ATTORNEY
EXHIBIT INDEX