content: <HTML><HEAD>
  <TITLE>Form 8-K</TITLE>
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  <HR SIZE="3" NOSHADE COLOR="#000000" ALIGN="left"><P STYLE="margin-top:0px;margin-bottom:-6px"><FONT SIZE="1">&nbsp;</FONT></P><P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
  FACE="Times New Roman" SIZE="5" COLOR="#000000"><B>UNITED STATES </B></FONT></P><P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="5" COLOR="#000000"><B>SECURITIES AND EXCHANGE COMMISSION </B></FONT></P><P
  STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="3" COLOR="#000000"><B>WASHINGTON, D.C. 20549 </B></FONT></P><P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><HR WIDTH="17%"
  SIZE="1" NOSHADE COLOR="#000000"><P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="5" COLOR="#000000"><B>FORM 8-K
  </B></FONT></P><P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="3" COLOR="#000000"><B>CURRENT REPORT </B></FONT></P><P
  STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="3" COLOR="#000000"><B>Pursuant to Section 13 or 15(d) of </B></FONT></P><P
  STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="3" COLOR="#000000"><B>The Securities Exchange Act of 1934 </B></FONT></P><P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><P
  STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000"><B>Date of Report (Date of Earliest Event Reported): </B></FONT></P><P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
  FACE="Times New Roman" SIZE="2" COLOR="#000000"><B>APRIL 24, 2003 </B></FONT></P><P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><HR WIDTH="17%" SIZE="1" NOSHADE COLOR="#000000"><P
  STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="6" COLOR="#000000"><B>KOSAN BIOSCIENCES INCORPORATED </B></FONT></P><P
  STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1" COLOR="#000000"><B>(Exact name of registrant specified in its charter) </B></FONT></P><P STYLE="margin-top:0px;margin-bottom:0px"><FONT
  SIZE="1">&nbsp;</FONT></P>
  <TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">
  
  <TR>
  <TD VALIGN="top" ALIGN="center" WIDTH="31%"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000"><B>Delaware</B></FONT></P></TD>
  <TD VALIGN="bottom" WIDTH="3%"><FONT FACE="Times New Roman" SIZE="1">&nbsp;</FONT></TD>
  <TD VALIGN="bottom" ALIGN="center" WIDTH="31%"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000"><B>000-31633</B></FONT></P></TD>
  <TD VALIGN="bottom" WIDTH="3%"><FONT FACE="Times New Roman" SIZE="1">&nbsp;</FONT></TD>
  <TD VALIGN="bottom" ALIGN="center" WIDTH="31%"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000"><B>94-3217016</B></FONT></P></TD></TR>
  <TR>
  <TD VALIGN="top" ALIGN="center" WIDTH="31%"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1" COLOR="#000000"><B>(State or other jurisdiction</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"
  ALIGN="center"><FONT FACE="Times New Roman" SIZE="1" COLOR="#000000"><B>of incorporation)</B></FONT></P></TD>
  <TD VALIGN="bottom" WIDTH="3%"><FONT FACE="Times New Roman" SIZE="1">&nbsp;</FONT></TD>
  <TD VALIGN="top" ALIGN="center" WIDTH="31%"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1" COLOR="#000000"><B>(Commission File Number)</B></FONT></P></TD>
  <TD VALIGN="bottom" WIDTH="3%"><FONT FACE="Times New Roman" SIZE="1">&nbsp;</FONT></TD>
  <TD VALIGN="bottom" ALIGN="center" WIDTH="31%"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1" COLOR="#000000"><B>(IRS Employee</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"
  ALIGN="center"><FONT FACE="Times New Roman" SIZE="1" COLOR="#000000"><B>Identification No.)</B></FONT></P></TD></TR>
  </TABLE><P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
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  <TD VALIGN="top" ALIGN="center" WIDTH="48%"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000"><B>3832 Bay Center Place Hayward, Ca</B></FONT></P></TD>
  <TD VALIGN="bottom" WIDTH="3%"><FONT FACE="Times New Roman" SIZE="1">&nbsp;</FONT></TD>
  <TD VALIGN="top" ALIGN="center" WIDTH="48%"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000"><B>94545</B></FONT></P></TD></TR>
  <TR>
  <TD VALIGN="top" ALIGN="center" WIDTH="48%"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1" COLOR="#000000"><B>(Address of principal executive offices)</B></FONT></P></TD>
  <TD VALIGN="bottom" WIDTH="3%"><FONT FACE="Times New Roman" SIZE="1">&nbsp;</FONT></TD>
  <TD VALIGN="top" ALIGN="center" WIDTH="48%"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1" COLOR="#000000"><B>(Zip Code)</B></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 FACE="Times New Roman" SIZE="2"
  COLOR="#000000"><B>Registrant&#146;s Telephone, Including Area Code: (510) 732-8400 </B></FONT></P><P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><HR SIZE="3" NOSHADE COLOR="#000000" ALIGN="left">
  
  <p Style='page-break-before:always'>
  <HR  SIZE="3" COLOR="#999999" WIDTH="100%" ALIGN="CENTER">
  
  <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><P STYLE="margin-top:0px;margin-bottom:0px; margin-left:2%; text-indent:-2%"><FONT FACE="Times New Roman" SIZE="2"
  COLOR="#000000">Item 7. FINANCIAL STATEMENTS AND EXHIBITS. </FONT></P><P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><P STYLE="margin-top:0px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"
  COLOR="#000000">(c) EXHIBITS </FONT></P><P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
  <TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">
  
  <TR>
  <TD VALIGN="bottom" ALIGN="center"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1" COLOR="#000000">Exhibit</FONT></P><HR WIDTH="34" SIZE="1" NOSHADE COLOR="#000000"></TD>
  <TD VALIGN="bottom" WIDTH="3%"><FONT FACE="Times New Roman" SIZE="1">&nbsp;&nbsp;</FONT></TD>
  <TD VALIGN="bottom" WIDTH="93%"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="1" COLOR="#000000">Description</FONT></P><HR WIDTH="60" SIZE="1" NOSHADE ALIGN="left" COLOR="#000000"></TD></TR>
  <TR>
  <TD VALIGN="top" ALIGN="center" WIDTH="6%"> <P STYLE="margin-top:0px;margin-bottom:0px; margin-left:2%; text-indent:-2%" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000">99.1</FONT></P></TD>
  <TD VALIGN="bottom" WIDTH="3%"><FONT FACE="Times New Roman" SIZE="1">&nbsp;&nbsp;</FONT></TD>
  <TD VALIGN="bottom" WIDTH="93%"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000">Press Release dated April 24, 2003, relating to the Company&#146;s financial results for the quarter ended March 31,
  2003.</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; margin-left:2%; text-indent:-2%"><FONT FACE="Times New Roman" SIZE="2"
  COLOR="#000000">Item 9. REGULATION FD DISCLOSURE. </FONT></P><P STYLE="margin-top:0px;margin-bottom:-6px"><FONT SIZE="1">&nbsp;</FONT></P><P STYLE="margin-top:0px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2"
  COLOR="#000000">In accordance with SEC Release No. 33-8216, the information in this Current Report on Form 8-K is being furnished to, but not filed with, the Securities and Exchange Commission solely under Item 12 of Form 8-K, &#147;Results of
  Operations and Financial Condition.&#148; </FONT></P><P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><P STYLE="margin-top:0px;margin-bottom:0px; margin-left:2%; text-indent:-2%"><FONT FACE="Times New Roman" SIZE="2"
  COLOR="#000000">Item 12. RESULTS OF OPERATIONS AND FINANCIAL CONDITION. </FONT></P><P STYLE="margin-top:0px;margin-bottom:-6px"><FONT SIZE="1">&nbsp;</FONT></P><P STYLE="margin-top:0px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman"
  SIZE="2" COLOR="#000000">On April 24, 2003, Kosan Biosciences Incorporated (the &#147;Company&#148;) announced via a press release the results of its operations for the quarter ended March 31, 2003. A copy of the Company&#146;s press release is
  attached hereto as Exhibit 99.1. </FONT></P>
  
  <p Style='page-break-before:always'>
  <HR  SIZE="3" COLOR="#999999" WIDTH="100%" ALIGN="CENTER">
  
  <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000">SIGNATURE
  </FONT></P><P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><P STYLE="margin-top:0px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000">Pursuant to the requirements of the Securities
  Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. </FONT></P><P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><DIV
  STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right">
  <TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="40%" BORDER="0">
  
  <TR>
  <TD VALIGN="top" COLSPAN="3" WIDTH="37%"> <P STYLE="margin-top:0px;margin-bottom:0px; margin-left:2%; text-indent:-2%"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000">K<SMALL>OSAN</SMALL> B<SMALL>IOSCIENCES</SMALL>
  I<SMALL>NCORPORATED</SMALL></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px; margin-left:2%; text-indent:-2%"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000">(Registrant)</FONT></P></TD></TR>
  <TR>
  <TD HEIGHT="16"></TD></TR>
  <TR>
  <TD VALIGN="top" WIDTH="2%"> <P STYLE="margin-top:0px;margin-bottom:0px; margin-left:2%; text-indent:-2%"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000">By:</FONT></P></TD>
  <TD VALIGN="bottom" WIDTH="3%"><FONT FACE="Times New Roman" SIZE="1">&nbsp;</FONT></TD>
  <TD VALIGN="top" ALIGN="center" WIDTH="37%"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000">/s/&nbsp;&nbsp;&nbsp;&nbsp;D<SMALL>ANIEL</SMALL> V. S<SMALL>ANTI</SMALL>, M.D.,
  P<SMALL>H</SMALL>.D&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P><HR SIZE="1" NOSHADE COLOR="#000000" ALIGN="left"></TD></TR>
  <TR>
  <TD><FONT SIZE="1">&nbsp;</FONT></TD>
  <TD VALIGN="bottom" WIDTH="3%"><FONT FACE="Times New Roman" SIZE="1">&nbsp;</FONT></TD>
  <TD VALIGN="bottom" ALIGN="center" WIDTH="37%"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1" COLOR="#000000">Daniel V. Santi, M.D., Ph.D</FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"
  ALIGN="center"><FONT FACE="Times New Roman" SIZE="1" COLOR="#000000">Chairman and Chief Executive Officer</FONT></P></TD></TR>
  </TABLE></DIV><P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><P STYLE="margin-top:0px;margin-bottom:0px; margin-left:2%; text-indent:-2%"><FONT FACE="Times New Roman" SIZE="2"
  COLOR="#000000">Dated: April 25, 2003 </FONT></P>
  
  <p Style='page-break-before:always'>
  <HR  SIZE="3" COLOR="#999999" WIDTH="100%" ALIGN="CENTER">
  
  <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P><P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000">EXHIBIT INDEX
  </FONT></P><P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
  <TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">
  
  <TR>
  <TD VALIGN="bottom" ALIGN="center"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1" COLOR="#000000">Exhibit</FONT></P><HR WIDTH="34" SIZE="1" NOSHADE COLOR="#000000"></TD>
  <TD VALIGN="bottom" WIDTH="3%"><FONT FACE="Times New Roman" SIZE="1">&nbsp;&nbsp;</FONT></TD>
  <TD VALIGN="bottom" WIDTH="93%"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="1" COLOR="#000000">Description</FONT></P><HR WIDTH="60" SIZE="1" NOSHADE ALIGN="left" COLOR="#000000"></TD></TR>
  <TR>
  <TD HEIGHT="5"></TD></TR>
  <TR>
  <TD VALIGN="top" ALIGN="right" WIDTH="6%"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000">99.1</FONT></P></TD>
  <TD VALIGN="bottom" WIDTH="3%"><FONT FACE="Times New Roman" SIZE="1">&nbsp;&nbsp;</FONT></TD>
  <TD VALIGN="bottom" WIDTH="93%"> <P STYLE="margin-top:0px;margin-bottom:0px; margin-left:2%; text-indent:-2%"><FONT FACE="Times New Roman" SIZE="2" COLOR="#000000">Press Release dated April 24, 2003, relating to the Company&#146;s financial results
  for the quarter ended March 31, 2003.</FONT></P></TD></TR>
  </TABLE><P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
  </BODY></HTML>
metadata_documents: [{"type": "8-K", "sequence": "1", "filename": "d8k.htm", "description": "FORM 8-K", "secsgml_size_bytes": 14001}]
metadata_filer: {"company-data": {"conformed-name": "KOSAN BIOSCIENCES INC", "cik": "0001110206", "assigned-sic": "8731", "irs-number": "943217016", "state-of-incorporation": "CA", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "8-K", "act": "34", "file-number": "000-31633", "film-number": "03666222"}, "business-address": {"street1": "3832 BAY CENTER PLACE", "city": "HAYWARD", "state": "CA", "zip": "94545", "phone": "5107328400"}, "mail-address": {"street1": "3832 BAY CENTER PLACE", "city": "HAYWARD", "state": "CA", "zip": "94545"}}
text: Form 8-K
  UNITED STATES
  SECURITIES AND EXCHANGE COMMISSION
  WASHINGTON, D.C. 20549
  FORM 8-K
  CURRENT REPORT
  Pursuant to Section 13 or 15(d) of
  The Securities Exchange Act of 1934
  Date of Report (Date of Earliest Event Reported):
  APRIL 24, 2003
  KOSAN BIOSCIENCES INCORPORATED
  (Exact name of registrant specified in its charter)
  Delaware
  000-31633
  94-3217016
  (State or other jurisdiction
  of incorporation)
  (Commission File Number)
  (IRS Employee
  Identification No.)
  3832 Bay Center Place Hayward, Ca
  94545
  (Address of principal executive offices)
  (Zip Code)
  Registrant's Telephone, Including Area Code: (510) 732-8400
  Item 7. FINANCIAL STATEMENTS AND EXHIBITS.
  (c) EXHIBITS
  Exhibit
  Description
  99.1
  Press Release dated April 24, 2003, relating to the Company's financial results for the quarter ended March 31,
  2003.
  Item 9. REGULATION FD DISCLOSURE.
  In accordance with SEC Release No. 33-8216, the information in this Current Report on Form 8-K is being furnished to, but not filed with, the Securities and Exchange Commission solely under Item 12 of Form 8-K, "Results of
  Operations and Financial Condition."
  Item 12. RESULTS OF OPERATIONS AND FINANCIAL CONDITION.
  On April 24, 2003, Kosan Biosciences Incorporated (the "Company") announced via a press release the results of its operations for the quarter ended March 31, 2003. A copy of the Company's press release is
  attached hereto as Exhibit 99.1.
  SIGNATURE
  Pursuant to the requirements of the Securities
  Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.
  K
  OSAN
  B
  IOSCIENCES
  I
  NCORPORATED
  (Registrant)
  By:
  /s/    D
  ANIEL
  V. S
  ANTI
  , M.D.,
  P
  H
  .D
  Daniel V. Santi, M.D., Ph.D
  Chairman and Chief Executive Officer
  Dated: April 25, 2003
  EXHIBIT INDEX
  Exhibit
  Description
  99.1
  Press Release dated April 24, 2003, relating to the Company's financial results
  for the quarter ended March 31, 2003.