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<TITLE></TITLE>
</HEAD>
<BODY>
<DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 18pt; FONT-FAMILY: Times New Roman"><STRONG>UNITED
STATES</STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 18pt; FONT-FAMILY: Times New Roman"><STRONG>SECURITIES
AND EXCHANGE COMMISSION</STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>Washington,
D.C. 20549</STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 18pt; FONT-FAMILY: Times New Roman"><STRONG>FORM
8-K</STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>CURRENT
REPORT</STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>PURSUANT
TO SECTION 13 OR 15(D) OF THE</STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>SECURITIES
EXCHANGE ACT OF 1934</STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>Date
of Report (Date of earliest event reported): March 1, 2005</STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 24pt; FONT-FAMILY: Times New Roman"><STRONG>Sirna
Therapeutics, Inc.</STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 7pt; FONT-FAMILY: Times New Roman, serif"><STRONG>(Exact
name of registrant as specified in its charter)</STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><BR></DIV>
<DIV>
<TABLE cellSpacing=0 cellPadding=0 width="100%">
  <TR>
    <TD vAlign=top align=middle width="35%">
      <DIV
      style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
      align=center><FONT
      style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>Delaware
      </STRONG></FONT></DIV></TD>
    <TD vAlign=top align=left width="1%">&nbsp;</TD>
    <TD vAlign=top align=middle width="16%">
      <DIV
      style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
      align=center><FONT
      style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>0-27914
      </STRONG></FONT></DIV></TD>
    <TD vAlign=top align=left width="1%">&nbsp;</TD>
    <TD vAlign=top align=middle width="29%">
      <DIV
      style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
      align=center><FONT
      style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>34-1697351
      </STRONG></FONT></DIV></TD>
    <TD vAlign=top align=middle width="1%">&nbsp;</TD></TR>
  <TR>
    <TD vAlign=top align=middle width="35%">
      <DIV
      style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
      align=center><FONT
      style="DISPLAY: inline; FONT-SIZE: 7pt; FONT-FAMILY: Times New Roman, serif"><STRONG>(State
      or other jurisdiction </STRONG></FONT></DIV>
      <DIV
      style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
      align=center><FONT
      style="DISPLAY: inline; FONT-SIZE: 7pt; FONT-FAMILY: Times New Roman, serif"><STRONG>of
      incorporation) </STRONG></FONT></DIV></TD>
    <TD vAlign=top align=left width="1%">&nbsp;</TD>
    <TD vAlign=top align=middle width="16%">
      <DIV
      style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
      align=center><FONT
      style="DISPLAY: inline; FONT-SIZE: 7pt; FONT-FAMILY: Times New Roman, serif"><STRONG>(Commission
      File No.) </STRONG></FONT></DIV></TD>
    <TD vAlign=top align=left width="1%">&nbsp;</TD>
    <TD vAlign=top align=middle width="29%">
      <DIV
      style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
      align=center><FONT
      style="DISPLAY: inline; FONT-SIZE: 7pt; FONT-FAMILY: Times New Roman, serif"><STRONG>(I.R.S.
      Employer </STRONG></FONT></DIV>
      <DIV
      style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
      align=center><FONT
      style="DISPLAY: inline; FONT-SIZE: 7pt; FONT-FAMILY: Times New Roman, serif"><STRONG>Identification
      Number </STRONG></FONT></DIV></TD>
    <TD vAlign=top align=middle width="1%">&nbsp;</TD></TR></TABLE></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><BR></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>2950
Wilderness Place </STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><BR></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>Boulder,
Colorado 80301 </STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><BR></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 7pt; FONT-FAMILY: Times New Roman, serif"><STRONG>(Address
of principal executive offices) </STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><BR></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>Registrant's
telephone number, including area code: (303) 449-6500 </STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><BR></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>N/A
</STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><BR></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 7pt; FONT-FAMILY: Times New Roman, serif"><STRONG>(Former
name or former address, if changed since last report.) </STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Check the
appropriate box below if the Form 8-K filing is intended to simultaneously
satisfy the filing obligation of the registrant under any of the following
provisions:</FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Wingdings">o</FONT><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"> Written
communications pursuant to Rule 425 under the Securities Act (17 CFR
230.425)</FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Wingdings">o</FONT><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR
240.14a-12)</FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Wingdings">o</FONT><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act
(17 CFR 240.14d-2(b))</FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Wingdings">o</FONT><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act
(17 CFR 240.13e-4(c))</FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><FONT size=2></FONT>&nbsp;</DIV>
<DIV id=PGBRK style="MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt">
<DIV id=FTR>
<DIV id=GLFTR style="WIDTH: 100%" align=left><FONT
style="DISPLAY: inline; FONT-SIZE: 8pt; COLOR: #000000; FONT-FAMILY: Times New Roman"></FONT></DIV></DIV>
<DIV id=PN style="PAGE-BREAK-AFTER: always">
<DIV style="WIDTH: 100%; TEXT-ALIGN: center"><FONT
style="DISPLAY: inline; FONT-SIZE: 8pt" face="Times New Roman"></FONT></DIV>
<DIV style="WIDTH: 100%; TEXT-ALIGN: center">
<HR color=#000000 noShade SIZE=2>
</DIV></DIV>
<DIV id=HDR>
<DIV id=GLHDR style="WIDTH: 100%" align=right><FONT
style="DISPLAY: inline; FONT-SIZE: 8pt; COLOR: #000000; FONT-FAMILY: Times New Roman"></FONT></DIV></DIV></DIV>
<DIV>
<TABLE cellSpacing=0 cellPadding=0 width="100%"></TABLE>
<DIV>&nbsp;</DIV>
<DIV>&nbsp;</DIV>
<DIV>
<TABLE cellSpacing=0 cellPadding=0 width="100%">
  <TR>
    <TD vAlign=top align=left width="10%">
      <DIV
      style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
      align=left><FONT
      style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>ITEM&nbsp;7.01
      </STRONG></FONT></DIV></TD>
    <TD vAlign=top align=left width="1%">&nbsp;</TD>
    <TD vAlign=top align=left width="68%">
      <DIV
      style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
      align=left><FONT
      style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>REGULATION
      FD DISCLOSURE</STRONG></FONT></DIV></TD></TR></TABLE></DIV></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><BR></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Sirna
Therapeutics, Inc. (the &#8220;Company&#8221;) issued a press release on Tuesday, March 1,
2005 that Martin Schmieg, </FONT><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Senior
Vice President and Chief Financial Officer of the Company</FONT><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">, will
present at the Leerink Swann &amp; Company/MEDACorp Inaugural Health Care
Conference on March 1, 2005 at 12:00 p.m., noon, EST. The conference will be
held in New York City.</FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><BR></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">The
presentation will be available via live webcast beginning March 1 and can be
found at the Company&#8217;s web site at http://www.sirna.com. The webcast will also
be archived on the Company&#8217;s web site for 30 days through March 31,
2005.</FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><BR></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">A copy of
the press release is furnished herewith as Exhibit 99.1 and is incorporated
herein by reference. The information contained in this Item 7.01, including the
accompanying exhibit, is being furnished and shall not be deemed to be &#8220;filed&#8221;
for purposes of Section 18 of the Securities Exchange Act of 1934, as amended
(&#8220;Exchange Act&#8221;), or otherwise subject to the liability of that section. The
information contained in this Item 7.01, including the accompanying exhibit,
shall not be incorporated by reference into any filing under the Securities Act
of 1933, as amended, or the Exchange Act, whether made before or after the date
hereof, except as shall be expressly set forth by specific reference in such
filing.</FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><BR></DIV>
<DIV>
<TABLE cellSpacing=0 cellPadding=0 width="100%">
  <TR>
    <TD vAlign=top align=left width="10%">
      <DIV
      style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
      align=left><FONT
      style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>ITEM&nbsp;9.01
      </STRONG></FONT></DIV></TD>
    <TD vAlign=top align=left width="1%">&nbsp;</TD>
    <TD vAlign=top align=left width="68%">
      <DIV
      style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
      align=left><FONT
      style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>FINANCIAL
      STATEMENTS AND EXHIBITS</STRONG></FONT></DIV></TD></TR></TABLE></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><BR></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">(c)
Exhibits. </FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"></FONT>&nbsp;</DIV>
<DIV>
<TABLE cellSpacing=0 cellPadding=0 width="100%">
  <TR>
    <TD vAlign=top align=left width="1%">&nbsp;</TD>
    <TD vAlign=top align=left width="9%">
      <DIV
      style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
      align=left><FONT
      style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">99.1
      </FONT></DIV></TD>
    <TD vAlign=top align=left width="67%">
      <DIV
      style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
      align=left><FONT
      style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Press
      Release issued by Sirna Therapeutics, Inc. on</FONT><FONT
      style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">
      March 1</FONT><FONT
      style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">,
      2005.</FONT></DIV></TD></TR></TABLE></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><BR></DIV><BR>
<DIV id=PGBRK style="MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; MARGIN-RIGHT: 0pt">
<DIV id=FTR>
<DIV id=GLFTR style="WIDTH: 100%" align=left><FONT
style="DISPLAY: inline; FONT-SIZE: 8pt; COLOR: #000000; FONT-FAMILY: Times New Roman"></FONT></DIV></DIV>
<DIV id=PN style="PAGE-BREAK-AFTER: always">
<DIV style="WIDTH: 100%; TEXT-ALIGN: center"><FONT
style="DISPLAY: inline; FONT-SIZE: 8pt" face="Times New Roman"></FONT></DIV>
<DIV style="WIDTH: 100%; TEXT-ALIGN: center">
<HR color=#000000 noShade SIZE=2>
</DIV></DIV>
<DIV id=HDR>
<DIV id=GLHDR style="WIDTH: 100%" align=right><FONT
style="DISPLAY: inline; FONT-SIZE: 8pt; COLOR: #000000; FONT-FAMILY: Times New Roman"></FONT></DIV></DIV></DIV><BR>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=center><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman"><STRONG>SIGNATURES</STRONG></FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 36pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=left><FONT
style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Pursuant
to the requirements of the Securities Exchange Act of 1934, as amended, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized. </FONT></DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify>&nbsp;</DIV>
<DIV
style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
align=justify><FONT size=2>
<TABLE cellSpacing=0 cellPadding=0 width="100%" align=center bgColor=#ffffff
border=0>
  <TR vAlign=top bgColor=#ffffff>
    <TD width="50%"><FONT face="Times New Roman" size=2>&nbsp;</FONT></TD>
    <TD width="1%"><FONT face="Times New Roman" size=2>&nbsp;</FONT></TD>
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    <TD><FONT face="Times New Roman" size=2>&nbsp;</FONT></TD>
    <TD colSpan=2><FONT face="Times New Roman" size=2><STRONG>SIRNA
      THERAPEUTICS, INC.<BR></STRONG>(Registrant)</FONT></TD></TR>
  <TR vAlign=top bgColor=#ffffff>
    <TD><FONT face="Times New Roman" size=2>&nbsp;<BR>&nbsp;</FONT></TD>
    <TD><FONT face="Times New Roman" size=2>&nbsp;<BR>&nbsp;</FONT></TD>
    <TD><FONT face="Times New Roman" size=2>&nbsp;<BR>&nbsp;</FONT></TD></TR>
  <TR vAlign=top bgColor=#ffffff>
    <TD><FONT face="Times New Roman" size=2>Date:&nbsp;March 1, 2005</FONT></TD>
    <TD><FONT face="Times New Roman" size=2>By:&nbsp;&nbsp;</FONT></TD>
    <TD><FONT face="Times New Roman" size=2>/s/&nbsp;Howard W.
  Robin</FONT></TD></TR>
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    <TD colSpan=2><FONT face="Times New Roman" size=1>&nbsp;</FONT></TD>
    <TD align=left>
      <HR align=left width="80%" color=#000000 noShade SIZE=2>
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    <TD colSpan=2><FONT face="Times New Roman" size=2>&nbsp;</FONT></TD>
    <TD><FONT face="Times New Roman" size=2>Howard W. Robin&nbsp;<BR>President
      and Chief Executive Officer</FONT></TD></TR></TABLE></FONT></DIV>
<DIV>&nbsp;</DIV>
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style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
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align=center><FONT
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INDEX</STRONG></FONT></DIV>
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style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
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      align=left><FONT
      style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">99.1
      </FONT></DIV></TD>
    <TD vAlign=top align=left width="70%">
      <DIV
      style="DISPLAY: block; MARGIN-LEFT: 0pt; TEXT-INDENT: 0pt; LINE-HEIGHT: 1.25; MARGIN-RIGHT: 0pt"
      align=left><FONT
      style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">Press
      Release issued by Sirna Therapeutics, Inc. on </FONT><FONT
      style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">March
      1</FONT><FONT
      style="DISPLAY: inline; FONT-SIZE: 10pt; FONT-FAMILY: Times New Roman">,
      2005.</FONT></DIV></TD></TR></TABLE></DIV>
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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): March 1, 2005
Sirna
Therapeutics, Inc.
(Exact
name of registrant as specified in its charter)
Delaware
0-27914
34-1697351
(State
      or other jurisdiction
of
      incorporation)
(Commission
      File No.)
(I.R.S.
      Employer
Identification
      Number
2950
Wilderness Place
Boulder,
Colorado 80301
(Address
of principal executive offices)
Registrant's
telephone number, including area code: (303) 449-6500
N/A
(Former
name or former address, if changed since last report.)
Check the
appropriate box below if the Form 8-K filing is intended to simultaneously
satisfy the filing obligation of the registrant under any of the following
provisions:
o
Written
communications pursuant to Rule 425 under the Securities Act (17 CFR
230.425)
o
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR
240.14a-12)
o
Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act
(17 CFR 240.14d-2(b))
o
Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act
(17 CFR 240.13e-4(c))
ITEM 7.01
REGULATION
      FD DISCLOSURE
Sirna
Therapeutics, Inc. (the "Company") issued a press release on Tuesday, March 1,
2005 that Martin Schmieg,
Senior
Vice President and Chief Financial Officer of the Company
, will
present at the Leerink Swann & Company/MEDACorp Inaugural Health Care
Conference on March 1, 2005 at 12:00 p.m., noon, EST. The conference will be
held in New York City.
The
presentation will be available via live webcast beginning March 1 and can be
found at the Company's web site at http://www.sirna.com. The webcast will also
be archived on the Company's web site for 30 days through March 31,
2005.
A copy of
the press release is furnished herewith as Exhibit 99.1 and is incorporated
herein by reference. The information contained in this Item 7.01, including the
accompanying exhibit, is being furnished and shall not be deemed to be "filed"
for purposes of Section 18 of the Securities Exchange Act of 1934, as amended
("Exchange Act"), or otherwise subject to the liability of that section. The
information contained in this Item 7.01, including the accompanying exhibit,
shall not be incorporated by reference into any filing under the Securities Act
of 1933, as amended, or the Exchange Act, whether made before or after the date
hereof, except as shall be expressly set forth by specific reference in such
filing.
ITEM 9.01
FINANCIAL
      STATEMENTS AND EXHIBITS
(c)
Exhibits.
99.1
Press
      Release issued by Sirna Therapeutics, Inc. on
March 1
,
      2005.
SIGNATURES
Pursuant
to the requirements of the Securities Exchange Act of 1934, as amended, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.
SIRNA
      THERAPEUTICS, INC.
(Registrant)
Date: March 1, 2005
By:
/s/ Howard W.
  Robin
Howard W. Robin
President
      and Chief Executive Officer
EXHIBIT
INDEX
99.1
Press
      Release issued by Sirna Therapeutics, Inc. on
March
      1
,
      2005.