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Proc-Type: 2001,MIC-CLEAR
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<SEC-DOCUMENT>0001062822-09-000115.txt : 20091102
<SEC-HEADER>0001062822-09-000115.hdr.sgml : 20091102
<ACCEPTANCE-DATETIME>20090916123439
<PRIVATE-TO-PUBLIC>
ACCESSION NUMBER:		0001062822-09-000115
CONFORMED SUBMISSION TYPE:	CORRESP
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20090916

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			LEXICON PHARMACEUTICALS, INC./DE
		CENTRAL INDEX KEY:			0001062822
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				760474169
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		CORRESP

	BUSINESS ADDRESS:	
		STREET 1:		8800 TECHNOLOGY FOREST PLACE
		CITY:			THE WOODLANDS
		STATE:			TX
		ZIP:			77381
		BUSINESS PHONE:		2818633000

	MAIL ADDRESS:	
		STREET 1:		8800 TECHNOLOGY FOREST PLACE
		CITY:			THE WOODLANDS
		STATE:			TX
		ZIP:			77381

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	LEXICON GENETICS INC/TX
		DATE OF NAME CHANGE:	20000126
</SEC-HEADER>
<DOCUMENT>
<TYPE>CORRESP
<SEQUENCE>1
<FILENAME>filename1.htm
<TEXT>
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  <head>
    <title>responseletter.htm</title>
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    <body bgcolor="#ffffff" style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">[LEXICON
PHARMACEUTICALS, INC. LETTERHEAD]</font></div>
    <div style="DISPLAY: block; TEXT-INDENT: 0pt"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="center"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">September
16, 2009</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="justify">&#160;</div>
    <div style="DISPLAY: block; TEXT-INDENT: 0pt"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Securities
and Exchange Commission</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Division
of Corporate Finance</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">100 F
Street, N.E.</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Washington,
D.C. 20549</font></div>
    <div style="DISPLAY: block; TEXT-INDENT: 0pt"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Attention:&#160;&#160;&#160;&#160;&#160;Ms.
Laura Crotty</font></div>
    <div style="DISPLAY: block; TEXT-INDENT: 0pt"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><font id="TAB1" style="MARGIN-LEFT: 54pt"></font>Re:&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;Lexicon
Pharmaceuticals, Inc.</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><font id="TAB1" style="MARGIN-LEFT: 90pt"></font>Registration Statement on Form
S-3</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><font id="TAB1" style="MARGIN-LEFT: 90pt"></font>Filed September 2, 2009</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><font id="TAB1" style="MARGIN-LEFT: 90pt"></font>File No. 333-161696</font></div>
    <div style="DISPLAY: block; TEXT-INDENT: 0pt"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Dear Ms.
Crotty:</font></div>
    <div style="DISPLAY: block; TEXT-INDENT: 0pt"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 36pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">On behalf
of Lexicon Pharmaceuticals, Inc., we submit the following responses to the
comments received on September 15, 2009 from the Securities and Exchange
Commission&#8217;s staff with respect to Lexicon&#8217;s registration statement on Form S-3
(File No. 333-161696).&#160;&#160;Your comments and our responses to those
comments are set forth below.</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="justify">&#160;</div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-WEIGHT: bold; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><font style="DISPLAY: inline; TEXT-DECORATION: underline">Documents Incorporated by
Reference, page 24</font></font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="justify">&#160;</div>
    <div>
      <table align="center" border="0" cellpadding="0" cellspacing="0" id="hangingindent" width="100%">
          <tr valign="top">
            <td style="WIDTH: 48px">
              <div style="MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">1.</font></div>
            </td>
            <td width="906">
              <div align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">We
      note the statement in your Form 10-K for the fiscal year ended December
      31, 2008, which is incorporated by reference into the above listed
      registration statement, that the company&#8217;s disclosure controls and
      procedures were &#8220;sufficiently effective&#8221; to ensure that the information
      required to be disclosed under the Securities Exchange Act of 1934 was
      gathered, analyzed and disclosed with adequate timeliness, accuracy and
      completeness, based on an evaluation of such controls and procedures at
      the end of the fiscal year.&#160;&#160;Given the use of the word
      &#8220;sufficiently&#8221; it remains unclear whether your chief executive officer and
      chief financial officer have concluded that your disclosure controls and
      procedures are effective.&#160;&#160;Please confirm that in your next Form
      10-K you will state, in clear and unqualified language, the conclusions
      reached by your chief executive officer and chief financial officer on the
      effectiveness of your disclosure controls and
  procedures.</font></div>
            </td>
          </tr>
      </table>
    </div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="justify">&#160;</div>
    <div>
      <table align="center" border="0" cellpadding="0" cellspacing="0" id="hangingindent" width="100%">
          <tr valign="top">
            <td style="WIDTH: 72pt">
              <div style="MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><font style="DISPLAY: inline; FONT-STYLE: italic">Response</font>:</font></div>
            </td>
            <td>
              <div align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">We
      confirm that in our next annual report on Form 10-K we will state, in
      clear and unqualified language, the conclusions reached by our chief
      executive officer and chief financial officer on the effectiveness of our
      disclosure controls and procedures.</font></div>
            </td>
          </tr>
      </table>
    </div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="justify">&#160;</div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 36pt; MARGIN-RIGHT: 0pt" align="left"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Please do
not hesitate to contact the undersigned at (281) 863-3321 with any comments or
questions concerning this letter or the above-referenced registration
statement.</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="justify">&#160;</div>
    <div style="DISPLAY: block; MARGIN-LEFT: 252pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Very
truly yours,</font></div>
    <div style="DISPLAY: block; TEXT-INDENT: 0pt"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 252pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">/s/
Jeffrey L. Wade</font></div>
    <div style="DISPLAY: block; TEXT-INDENT: 0pt"><br></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 252pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Jeffrey
L. Wade</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 252pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-STYLE: italic; FONT-FAMILY: Times New Roman">Executive
Vice President and</font></div>
    <div style="DISPLAY: block; MARGIN-LEFT: 252pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt" align="justify"><font style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-STYLE: italic; FONT-FAMILY: Times New Roman">General
Counsel</font></div>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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