<SUBMISSION>
<ACCESSION-NUMBER>0001193125-06-055616
<TYPE>FWP
<PUBLIC-DOCUMENT-COUNT>1
<FILING-DATE>20060316
<DATE-OF-FILING-DATE-CHANGE>20060316
<SUBJECT-COMPANY>
<COMPANY-DATA>
<CONFORMED-NAME>CERUS CORP
<CIK>0001020214
<ASSIGNED-SIC>2836
<IRS-NUMBER>680262011
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<FILING-VALUES>
<FORM-TYPE>FWP
<ACT>34
<FILE-NUMBER>333-67286
<FILM-NUMBER>06689933
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>2411 STANWELL DR
<CITY>CONCORD
<STATE>CA
<ZIP>94520
<PHONE>9252886000
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>2525 STANWELL DRIVE
<STREET2>STE 300
<CITY>CONCORD
<STATE>CA
<ZIP>94520
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>CERUS TECHNOLOGIES INC
<DATE-CHANGED>19960731
</FORMER-COMPANY>
</SUBJECT-COMPANY>
<FILED-BY>
<COMPANY-DATA>
<CONFORMED-NAME>CERUS CORP
<CIK>0001020214
<ASSIGNED-SIC>2836
<IRS-NUMBER>680262011
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<FILING-VALUES>
<FORM-TYPE>FWP
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>2411 STANWELL DR
<CITY>CONCORD
<STATE>CA
<ZIP>94520
<PHONE>9252886000
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>2525 STANWELL DRIVE
<STREET2>STE 300
<CITY>CONCORD
<STATE>CA
<ZIP>94520
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>CERUS TECHNOLOGIES INC
<DATE-CHANGED>19960731
</FORMER-COMPANY>
</FILED-BY>
<DOCUMENT>
<TYPE>FWP
<SEQUENCE>1
<FILENAME>dfwp.htm
<DESCRIPTION>FWP
<TEXT>
<HTML><HEAD>
<TITLE>FWP</TITLE>
</HEAD>
 <BODY BGCOLOR="WHITE">

 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">Filed pursuant to Rule&nbsp;433 </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT
FACE="Times New Roman" SIZE="2">Registration Statement No.&nbsp;333-67286 </FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">March&nbsp;16, 2006 </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>Free Writing Prospectus </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>Dated March&nbsp;16, 2006 </B></FONT></P>
<P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>4,500,000 Shares </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>Cerus
Corporation </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>Common Stock </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><I>This
free writing prospectus relates only to the securities described below and should be read together with the preliminary prospectus supplement dated February&nbsp;27, 2006 (including the base prospectus dated December&nbsp;17, 2001 and the documents
incorporated by reference therein) relating to these securities. </I></FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">

<TR>
<TD WIDTH="24%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="75%"></TD></TR>
<TR>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2"><B>Public offering price.</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">$8.75 per share, with an underwriting discount of $0.481 per&nbsp;share</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2"><B>Common stock to be outstanding after this offering.</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">26,957,729 shares, assuming no exercise of the over-allotment option</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">The number of shares of our common stock to be outstanding after this offering is based on 22,457,729 shares of capital stock outstanding as of December 31, 2005, and excludes an aggregate of
7,390,000 shares of common stock reserved for issuance under our equity compensation plans, of which 4,598,063 were subject to outstanding stock options as of December 31, 2005, at a weighted average exercise price of $13.025 (the &#147;Excluded
Securities&#148;).</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2"><B>Use of Proceeds.</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">We estimate that the net proceeds from this offering will be approximately $36.9&nbsp;million (or approximately $42.5&nbsp;million if the underwriters&#146; over-allotment option is exercised in
full), based on the public offering price of $8.75 per share, after deducting underwriting discounts and commissions and estimated offering expenses payable by us.</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT FACE="Times New Roman" SIZE="2"><B>As Adjusted Balance Sheet.</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">The following as adjusted balance sheet as of December 31, 2005 gives effect to the issuance and sale of 4,500,000 shares of our common stock in the offering at a public offering price of $8.75
per share, after deducting the underwriting discounts and commissions and estimated offering expenses payable by us.</FONT></TD></TR>
</TABLE> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">

<TR>
<TD WIDTH="84%"></TD>
<TD VALIGN="bottom" WIDTH="3%"></TD>
<TD></TD>
<TD></TD>
<TD></TD>
<TD VALIGN="bottom" WIDTH="3%"></TD>
<TD></TD>
<TD></TD>
<TD></TD></TR>
<TR>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" COLSPAN="6" ALIGN="center" STYLE="border-bottom:1px solid #000000"><FONT FACE="Times New Roman" SIZE="1"><B>December&nbsp;31, 2005</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD></TR>
<TR>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" COLSPAN="2" ALIGN="center" STYLE="border-bottom:1px solid #000000"><FONT FACE="Times New Roman" SIZE="1"><B>Actual</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" COLSPAN="2" ALIGN="center" STYLE="border-bottom:1px solid #000000"><FONT FACE="Times New Roman" SIZE="1"><B>As&nbsp;adjusted</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD></TR>
<TR>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" COLSPAN="6" ALIGN="center"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>(in&nbsp;thousands,&nbsp;except&nbsp;share</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px"
ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>and per share data)</B></FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD></TR>
<TR BGCOLOR="#cceeff">
<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2"><B>Balance Sheet:</B></FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Cash, cash equivalents and short term investments</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">$</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">45,805</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">$</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">82,716</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD></TR>
<TR BGCOLOR="#cceeff">
<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Stockholders' equity</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:3.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Preferred Stock, $0.001 par value per share; 5,000,000 shares authorized; 3,327 shares issued and outstanding, actual and as adjusted; $9,496
liquidation preference, actual and as adjusted</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">9,496</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">9,496</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD></TR>
<TR BGCOLOR="#cceeff">
<TD VALIGN="top"> <P STYLE="margin-left:3.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Common Stock, $0.001 par value per share; 50,000,000 shares authorized; 22,457,729 shares issued and outstanding, actual; 26,957,729 as
adjusted</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">23</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">27</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:5.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Additional paid-in capital</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">332,694</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">369,600</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD></TR>
<TR BGCOLOR="#cceeff">
<TD VALIGN="top"> <P STYLE="margin-left:5.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Accumulated other comprehensive loss</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">(295</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">(295</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">)</FONT></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:5.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Accumulated deficit</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">(306,643</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">)</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">(306,643</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">)</FONT></TD></TR>
<TR STYLE="font-size:1px">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" STYLE="border-top:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="border-top:1px solid #000000">&nbsp;</TD>
<TD>&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="border-top:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="border-top:1px solid #000000">&nbsp;</TD>
<TD>&nbsp;</TD></TR>
<TR BGCOLOR="#cceeff">
<TD VALIGN="top"> <P STYLE="margin-left:5.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Total stockholders' equity</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">35,275</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">72,185</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD></TR>
<TR STYLE="font-size:1px">
<TD VALIGN="bottom"></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" STYLE="border-top:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="border-top:1px solid #000000">&nbsp;</TD>
<TD>&nbsp;</TD>
<TD VALIGN="bottom">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="border-top:1px solid #000000">&nbsp;</TD>
<TD VALIGN="bottom" STYLE="border-top:1px solid #000000">&nbsp;</TD>
<TD>&nbsp;</TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:5.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2">Total capitalization</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">$</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">35,275</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">$</FONT></TD>
<TD VALIGN="bottom" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2">72,185</FONT></TD>
<TD NOWRAP VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">&nbsp;</FONT></TD></TR>
</TABLE>

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<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">

<TR>
<TD WIDTH="24%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="75%"></TD></TR>
<TR>
<TD VALIGN="top"> <P STYLE="margin-left:1.00em; text-indent:-1.00em"><FONT FACE="Times New Roman" SIZE="2"><B>Dilution.</B></FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">The net tangible book value of our common stock on December&nbsp;31, 2005 was approximately $35.3&nbsp;million, or $1.57 per share. After giving effect to the sale by us of 4,500,000 shares
of common stock in this offering at the public offering price of $8.75 per share and after deducting underwriting discounts and commissions and estimated offering expenses payable by us, our net tangible book value at December&nbsp;31, 2005 would
have been approximately $72.2&nbsp;million, or $2.68 per share. This represents an immediate increase in net tangible book value of $1.11 per share to existing stockholders and an immediate dilution of $6.07 per share to new investors purchasing
shares of common stock in this offering. If the underwriters exercise their over-allotment option in full, the as adjusted net tangible book value as of December&nbsp;31, 2005 would have been $2.81 per share, representing an increase to existing
stockholders of $1.24 per share, and there will be immediate dilution of $5.94 per share to new investors.</FONT></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom"><FONT FACE="Times New Roman" SIZE="2">The foregoing information is based on the number of shares of capital stock outstanding as of December 31, 2005 and does not take into account further dilution to new investors that could
occur upon the exercise or issuance of Excluded Securities with a per share exercise price or purchase price less than the public offering price.</FONT></TD></TR>
</TABLE> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><I>The issuer has filed a registration statement (including a prospectus and preliminary prospectus supplement)
with the Securities and Exchange Commission for the offering to which this communication relates. Before you invest, you should read the prospectus and preliminary prospectus supplement in that registration statement (including the documents
incorporated by reference therein) and other documents Cerus has filed with the Securities and Exchange Commission for more complete information about Cerus and this offering. You may get these documents for free by visiting EDGAR on the Securities
and Exchange Commission&#146;s web site at www.sec.gov. Alternatively, Cerus, any underwriter or any dealer participating in the offering will arrange to send you the prospectus and preliminary prospectus supplement if you request it by calling
1-925-288-6000. </I></FONT></P>
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</TEXT>
</DOCUMENT>
</SUBMISSION>
