<SUBMISSION>
<ACCESSION-NUMBER>0000950123-04-005871
<TYPE>10-Q
<PUBLIC-DOCUMENT-COUNT>3
<PERIOD>20040331
<FILING-DATE>20040506
<FILER>
<COMPANY-DATA>
<CONFORMED-NAME>REGENERON PHARMACEUTICALS INC
<CIK>0000872589
<ASSIGNED-SIC>2834
<IRS-NUMBER>133444607
<STATE-OF-INCORPORATION>NY
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<FILING-VALUES>
<FORM-TYPE>10-Q
<ACT>34
<FILE-NUMBER>000-19034
<FILM-NUMBER>04785073
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>777 OLD SAW MILL RIVER RD
<CITY>TARRYTOWN
<STATE>NY
<ZIP>10591-6707
<PHONE>9143477000
</BUSINESS-ADDRESS>
</FILER>
<DOCUMENT>
<TYPE>10-Q
<SEQUENCE>1
<FILENAME>y96986e10vq.htm
<DESCRIPTION>FORM 10-Q
<TEXT>
<HTML>
<HEAD>
<TITLE>FORM 10-Q</TITLE>
</HEAD>
<BODY bgcolor="#FFFFFF">
<!-- PAGEBREAK -->
<H5 align="left" style="page-break-before:always"><A HREF="#tocpage">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">

<P align="center" style="font-size: 14pt">UNITED STATES<BR>
SECURITIES AND EXCHANGE COMMISSION

<DIV align="center" style="font-size: 12pt">Washington, D.C. 20549
</DIV>

<P align="center" style="font-size: 18pt"><B>Form&nbsp;10-Q</B>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="5%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="93%">&nbsp;</TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">(Mark One)</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; font-size: 12pt">(X)
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top" style="font-size: 12pt">QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">For the quarterly period ended March&nbsp;31, 2004</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">OR</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; font-size: 12pt">(&nbsp;&nbsp; )
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top" style="font-size: 12pt">TRANSITION REPORT PURSUANT TO SECTION 13 OR 15 (d)&nbsp;OF THE SECURITIES EXCHANGE ACT OF 1934</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">For the transition period from&nbsp;<U>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</U>to&nbsp;<U>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</U></TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Commission File Number 0-19034</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>


<P align="center" style="font-size: 24pt">REGENERON PHARMACEUTICALS, INC.

<DIV align="center" style="font-size: 10pt"><HR align="center" size="1" noshade width="70%"></DIV>


<DIV align="center" style="font-size: 10pt">(Exact name of registrant as specified in its charter)</DIV>


<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="47%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="47%">&nbsp;</TD>
</TR>
<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom">
    <TD align="center" valign="top">New York<BR>
<HR align="center" size="1" noshade width="25%">
(State or other jurisdiction of<BR>
incorporation or organization)
</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">13-3444607<BR>
<HR align="center" size="1" noshade width="25%">
(I.R.S. Employer Identification No.)</TD>
</TR>

<TR valign="bottom">
    <TD align="center" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD align="center" valign="top">777 Old Saw Mill River Road<BR>
Tarrytown, New York<BR>
<HR align="center" size="1" noshade width="30%">
(Address of principal executive offices)
</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">10591-6707<BR>
<HR align="center" size="1" noshade width="25%">
(Zip Code)</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>



<P align="center" style="font-size: 10pt">(914)&nbsp;347-7000


<DIV align="center" style="font-size: 10pt"><HR align="center" size="1" noshade width="25%"></DIV>


<DIV align="center" style="font-size: 10pt">(Registrant&#146;s telephone number, including area code)</DIV>


<P align="left" style="font-size: 10pt">Indicate by check mark whether the registrant (1)&nbsp;has filed all reports
required to be filed by Section&nbsp;13 or 15(d) of the Securities Exchange
Act of 1934 during the preceding 12&nbsp;months (or for such shorter period
that the registrant was required to file such reports), and (2)&nbsp;has been
subject to such filing requirements for the past 90&nbsp;days.



<P align="center" style="font-size: 10pt">Yes&nbsp;(X)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;No&nbsp;(&nbsp;&nbsp;&nbsp;)


<P align="left" style="font-size: 10pt">Indicate by check mark whether the registrant is an accelerated filer (as
defined in Rule&nbsp;12b-2 of the Exchange Act).



<P align="center" style="font-size: 10pt">Yes&nbsp;(&nbsp;&nbsp;&nbsp;)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;No&nbsp;(X)


<P align="left" style="font-size: 10pt">Indicate the number of shares outstanding of each of the issuer&#146;s classes
of common stock as of April&nbsp;30, 2004:


<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="70%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="72%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="11%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="11%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD nowrap align="center"><B>Class of Common Stock</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Number of Shares</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Class&nbsp;A Stock, $0.001 par value</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,365,873</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Common Stock, $0.001 par value</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">53,276,634</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>




<P align="center" style="font-size: 10pt">&nbsp;
</DIV>

<!-- PAGEBREAK -->
<P><HR noshade><P>

<DIV style="font-family: 'Times New Roman',Times,serif">




<P align="center" style="font-size: 10pt"><B>REGENERON PHARMACEUTICALS, INC.<BR>
Table of Contents<BR>
March&nbsp;31, 2004</B>


<DIV align="left">
<!-- TOC -->
</DIV>
<DIV align="left">
<A name="tocpage"></A>
</DIV>
<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="10%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="80%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="39%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="40%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Page Numbers</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom">

<TD valign="top"><DIV style="margin-left:0px; text-indent:-0px"><A href="#101"><B>PART I
</B></A></DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><A href="#101"><B>FINANCIAL INFORMATION</B></A></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px"><A href="#102">Item&nbsp;1
</A></DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><A href="#102">Financial Statements</A></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="right" valign="top">&nbsp;</TD>
    <TD valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><A href="#103">Condensed balance sheets (unaudited)&nbsp;at March&nbsp;31, 2004
and December&nbsp;31, 2003
</A></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="left" valign="top">3</TD>
    <TD nowrap valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><A href="#104">Condensed statements of operations (unaudited)&nbsp;for the three
months ended March&nbsp;31, 2004 and 2003
</A></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="left" valign="top">4</TD>
    <TD nowrap valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><A href="#105">Condensed statement of stockholders&#146; equity (unaudited)&nbsp;for
the three months ended March&nbsp;31, 2004
</A></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="left" valign="top">5</TD>
    <TD nowrap valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><A href="#106">Condensed statements of cash flows (unaudited)&nbsp;for the
three months ended March&nbsp;31, 2004 and 2003
</A></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="left" valign="top">6</TD>
    <TD nowrap valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><A href="#107">Notes to condensed financial statements
</A></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="left" valign="top">7-14</TD>
    <TD nowrap valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px"><A href="#108">Item&nbsp;2
</A></DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><A href="#108">Management&#146;s Discussion and Analysis of Financial Condition and
Results of Operations
</A></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="left" valign="top">15-36</TD>
    <TD nowrap valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px"><A href="#109">Item&nbsp;3
</A></DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><A href="#109">Quantitative &#038; Qualitative Disclosure About Market Risk
</A></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="left" valign="top">36</TD>
    <TD nowrap valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px"><A href="#110">Item&nbsp;4
</A></DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><A href="#110">Controls and Procedures
</A></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="right" valign="top" nowrap>36-37</TD>
    <TD nowrap valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px"><A href="#111"><B>PART II</B>
</A></DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><A href="#111"><B>OTHER INFORMATION</B></A></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px"><A href="#112">Item&nbsp;1
</A></DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><A href="#112">Legal Proceedings
</A></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="left" valign="top">38</TD>
    <TD nowrap valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px"><A href="#113">Item&nbsp;6
</A></DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><A href="#113">Exhibits and Reports on Form&nbsp;8-K
</A></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="left" valign="top">38-39</TD>
    <TD nowrap valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD colspan="3" valign="top" align="left"><A href="#114"><B>SIGNATURE PAGE</B></A></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="left" valign="top">40</TD>
    <TD nowrap valign="top">&nbsp;</TD>
</TR>

<!-- End Table Body -->
<TR><TD colspan="9"><FONT size="2">&nbsp;<A HREF="y96986exv31.htm">EXHIBIT 31-302 CERTIFICATION OF CEO AND CFO</A></FONT></TD></TR>
<TR><TD colspan="9"><FONT size="2">&nbsp;<A HREF="y96986exv32.htm">EXHIBIT 32-906 CERTIFICATION OF CEO AND CFO</A></FONT></TD></TR>
</TABLE>
</DIV>


<DIV align="left">
<!-- /TOC -->
</DIV>

<P align="center" style="font-size: 10pt">&nbsp;
</DIV>

<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always"><A HREF="#tocpage">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">



<DIV align="left">
<A name="101"></A>
</DIV>

<P align="left" style="font-size: 10pt"><B>PART I. FINANCIAL INFORMATION</B>


<DIV align="left">
<A name="102"></A>
</DIV>

<DIV align="left" style="font-size: 10pt"><B>ITEM 1. FINANCIAL STATEMENTS</B></DIV>


<P align="left" style="font-size: 10pt"><B>REGENERON PHARMACEUTICALS, INC.</B>


<DIV align="left">
<A name="103"></A>
</DIV>

<DIV align="left" style="font-size: 10pt"><B>CONDENSED BALANCE SHEETS AT MARCH 31, 2004 AND DECEMBER 31, 2003 (Unaudited)</B><BR><B><I>(In thousands, except share data)</I></B></DIV>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="76%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>March 31,</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>December 31,</B></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2004</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2003</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD align="center"><DIV style="margin-left:50px; text-indent:-10px"><B>ASSETS</B></DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Current assets</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Cash and cash equivalents</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">174,034</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">118,285</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Marketable securities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">135,725</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">164,576</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Restricted marketable securities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">10,977</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">10,913</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Accounts receivable</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">59,882</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">15,529</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Prepaid expenses and other current assets</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,568</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">1,898</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Inventory</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">9,098</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">9,006</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Total current assets</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">392,284</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">320,207</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Marketable securities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">30,642</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">72,792</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Property, plant, and equipment, at cost, net of accumulated
depreciation and amortization</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">77,616</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">80,723</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Other assets</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">5,636</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">5,833</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Total assets</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">506,178</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">479,555</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD align="center"><DIV style="margin-left:40px; text-indent:-10px"><B>LIABILITIES and STOCKHOLDERS&#146; EQUITY</B></DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Current liabilities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Accounts payable and accrued expenses</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">18,947</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">18,933</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Deferred revenue, current portion</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">17,388</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">40,173</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Loan payable to Novartis Pharma AG</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">13,817</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Total current liabilities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">36,335</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">72,923</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Deferred revenue</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">65,621</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">68,830</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Notes payable</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">200,000</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">200,000</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Other long-term liabilities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">116</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">159</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Total liabilities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">302,072</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">341,912</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Commitments and contingencies</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Stockholders&#146; equity</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Preferred stock, $.01 par value; 30,000,000 shares authorized; issued and
outstanding-none</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Class&nbsp;A Stock, convertible, $.001 par value; 40,000,000 shares
authorized;<BR>
2,365,873 shares issued and outstanding in 2004 and 2003</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Common Stock, $.001 par value; 160,000,000 shares authorized;<BR>
53,270,395 shares issued and outstanding in 2004<BR>
53,165,635 shares issued and outstanding in 2003</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">53</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">53</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Additional paid-in capital</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">674,242</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">673,118</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Unearned compensation</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(3,363</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(4,101</TD>
    <TD nowrap>)</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Accumulated deficit</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(467,001</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(531,533</TD>
    <TD nowrap>)</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Accumulated other comprehensive income</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">173</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">104</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Total stockholders&#146; equity</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">204,106</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">137,643</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Total liabilities and stockholders&#146; equity</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">506,178</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">479,555</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>

<P align="center" style="font-size: 10pt"><B>The accompanying notes are an integral part of the financial statements.</B>

<P align="center" style="font-size: 10pt">3
</DIV>

<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always"><A HREF="#tocpage">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">





<P align="left" style="font-size: 10pt"><B>REGENERON PHARMACEUTICALS, INC.</B>


<DIV align="left">
<A name="104"></A>
</DIV>

<DIV align="left" style="font-size: 10pt"><B>CONDENSED STATEMENTS OF OPERATIONS (Unaudited)</B><BR>
<B><I>(In thousands, except per share data)</I></B></DIV>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="68%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="6%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="6%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="7"><B>Three months ended March 31,</B><HR size="1" noshade></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2004</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2003</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Revenues</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Contract research and development</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">41,610</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">9,213</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Research progress payments</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">17,770</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Contract manufacturing</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,610</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">712</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">61,990</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">9,925</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Expenses</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Research and development</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">32,181</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">34,390</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Contract manufacturing</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,225</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">666</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">General and administrative</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">3,790</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">3,459</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">38,196</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">38,515</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Income (loss)&nbsp;from operations</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">23,794</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">(</TD>
    <TD align="right">28,590</TD>
    <TD nowrap>)</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Other income (expense)</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Other contract income</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">42,750</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Investment income</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">1,124</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">1,208</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Interest expense</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(3,136</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(2,939</TD>
    <TD nowrap>)</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">40,738</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(1,731</TD>
    <TD nowrap>)</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Net income (loss)</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">64,532</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">($</TD>
    <TD align="right">30,321</TD>
    <TD nowrap>)</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Net income (loss)&nbsp;per share:</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Basic</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">1.17</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">($</TD>
    <TD align="right">0.68</TD>
    <TD nowrap>)</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Diluted</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">1.06</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">($</TD>
    <TD align="right">0.68</TD>
    <TD nowrap>)</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Weighted average shares outstanding:</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Basic</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">55,283</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">44,309</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Diluted</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">63,620</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">44,309</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>

<P align="center" style="font-size: 10pt"><B>The accompanying notes are an integral part of the financial statements.</B>

<P align="center" style="font-size: 10pt">4
</DIV>

<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always"><A HREF="#tocpage">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">


<P align="left" style="font-size: 10pt"><B>REGENERON PHARMACEUTICALS, INC.</B>


<DIV align="left">
<A name="105"></A>
</DIV>

<DIV align="left" style="font-size: 10pt"><B>CONDENSED STATEMENT OF STOCKHOLDERS&#146; EQUITY (Unaudited)<BR>
For the three months ended March&nbsp;31, 2004</B><BR>
<B><I>(In thousands)</I></B></DIV>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="68%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
</TR>


<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="7"><B>Class A Stock</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="7"><B>Common Stock</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Additional<BR>Paid-in</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Unearned</B></TD>
</TR>

<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Shares</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Amount</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Shares</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Amount</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Capital</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Compensation</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Balance, December&nbsp;31, 2003</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,366</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">2</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">53,166</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">53</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">673,118</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">($</TD>
    <TD align="right">4,101</TD>
    <TD nowrap>)</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Issuance of Common Stock in connection with
exercise of stock options</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">45</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">274</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Forfeitures of restricted Common Stock under
Long-Term Incentive
Plan,<BR>net of issuances</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(5</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(67</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">67</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Issuance of Common Stock in connection with
Company 401(k) Savings<BR>Plan contribution</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">64</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">917</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Amortization of unearned compensation</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">671</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Net income</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Change in net unrealized gain on
marketable securities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>


<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Balance, March&nbsp;31, 2004</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,366</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">2</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">53,270</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">53</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">674,242</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">($</TD>
    <TD align="right">3,363</TD>
    <TD nowrap>)</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<BR clear="all"><DIV align="right"

style="font-size: 10pt">[Additional columns below]</DIV><P align="left" style="font-size: 10pt">[Continued from above

table, first column(s) repeated]

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="72%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
</TR>

<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Accumulated</B></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Other</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Total</B></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Accumulated</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Comprehensive</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Stockholders&#146;</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Comprehensive</B></TD>
</TR>

<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Deficit</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Income</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Equity</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Income</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Balance, December&nbsp;31, 2003</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">($</TD>
    <TD align="right">531,533</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">104</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">137,643</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Issuance of Common Stock in connection with
exercise of stock options</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">274</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Forfeitures of restricted Common Stock under
Long-Term Incentive
Plan, net of issuances</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Issuance of Common Stock in connection with
Company 401(k) Savings
Plan contribution</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">917</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Amortization of unearned compensation</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">671</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Net income</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">64,532</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">64,532</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">64,532</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Change in net unrealized gain on
marketable securities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">69</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">69</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">69</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>


<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Balance, March&nbsp;31, 2004</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">($</TD>
    <TD align="right">467,001</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">173</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">204,106</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">64,601</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>



<P align="center" style="font-size: 10pt"><B>The accompanying notes are an integral part of the financial statements.</B>


<P align="center" style="font-size: 10pt">5

<P align="center" style="font-size: 10pt">
</DIV>


<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always"><A HREF="#tocpage">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">




<P align="left" style="font-size: 10pt"><B>REGENERON PHARMACEUTICALS, INC.</B>


<DIV align="left">
<A name="106"></A>
</DIV>

<DIV align="left" style="font-size: 10pt"><B>CONDENSED STATEMENTS OF CASH FLOWS (Unaudited)</B><BR>
<B><I>(In thousands)</I></B></DIV>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="76%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="7"><B>Three months ended March 31,</B><HR size="1" noshade></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2004</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2003</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Cash flows from operating activities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Net income (loss)</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">64,532</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">($</TD>
    <TD align="right">30,321</TD>
    <TD nowrap>)</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Adjustments to reconcile net income (loss)&nbsp;to net cash (used in)
provided by operating activities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Depreciation and amortization</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">3,773</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,288</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Non-cash compensation expense</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">671</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">587</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Non-cash expense related to a license agreement</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">13</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Forgiveness of loan payable to Novartis Pharma AG,
inclusive of accrued interest</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(17,770</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Changes in assets and liabilities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:40px; text-indent:-10px">Increase in accounts receivable</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(44,353</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(3,221</TD>
    <TD nowrap>)</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:40px; text-indent:-10px">(Increase) decrease in prepaid expenses and other assets</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(943</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">1,032</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:40px; text-indent:-10px">Decrease (increase)&nbsp;in inventory</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">188</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(1,324</TD>
    <TD nowrap>)</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:40px; text-indent:-10px">(Decrease) increase in deferred revenue</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(25,994</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">24,641</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:40px; text-indent:-10px">Increase in accounts payable, accrued expenses,
and other liabilities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">1,301</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">7,511</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:70px; text-indent:-10px">Total adjustments</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(83,114</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">31,514</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:70px; text-indent:-10px">Net cash (used in) provided by operating activities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(18,582</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">1,193</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Cash flows from investing activities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Purchases of marketable securities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(5,566</TD>
    <TD nowrap>)</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Purchases of restricted marketable securities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(5,500</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(5,500</TD>
    <TD nowrap>)</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Sales or maturities of marketable securities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">71,215</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">87,389</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Maturities of restricted marketable securities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">5,500</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">5,500</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Capital expenditures</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(985</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(20,004</TD>
    <TD nowrap>)</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:70px; text-indent:-10px">Net cash provided by investing activities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">70,230</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">61,819</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Cash flows from financing activities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Net proceeds from the issuance of stock</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">274</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">48,586</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Borrowings under loan payable</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">3,827</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Capital lease payments</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(89</TD>
    <TD nowrap>)</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:70px; text-indent:-10px">Net cash provided by financing activities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">4,101</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">48,497</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:70px; text-indent:-10px">Net increase in cash and cash equivalents</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">55,749</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">111,509</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Cash and cash equivalents at beginning of period</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">118,285</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">80,077</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:70px; text-indent:-10px">Cash and cash equivalents at end of period</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">174,034</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">191,586</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>



<P align="center" style="font-size: 10pt"><B>The accompanying notes are an integral part of the financial statements.</B>




<P align="center" style="font-size: 10pt">6
</DIV>

<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always"><A HREF="#tocpage">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">




<P align="left" style="font-size: 10pt"><B>REGENERON PHARMACEUTICALS, INC.</B>


<DIV align="left">
<A name="107"></A>
</DIV>

<DIV align="left" style="font-size: 10pt"><B>Notes to Condensed Financial Statements</B><BR>
<B><I>(Unless otherwise noted, dollars in thousands, except per share data)</I></B></DIV>


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right"><B>1.</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>Interim Financial Statements</B></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>The interim Condensed Financial Statements of Regeneron Pharmaceuticals, Inc.
(&#147;Regeneron&#148; or the &#147;Company&#148;) have been prepared in accordance with the
instructions to Form 10-Q and Article&nbsp;10 of Regulation&nbsp;S-X. Accordingly, they
do not include all information and disclosures necessary for a presentation of
the Company&#146;s financial position, results of operations, and cash flows in
conformity with generally accepted accounting principles. In the opinion of
management, these financial statements reflect all adjustments, consisting only
of normal recurring accruals, necessary for a fair presentation of the
Company&#146;s financial position, results of operations, and cash flows for such
periods. The results of operations for any interim periods are not necessarily
indicative of the results for the full year. The December&nbsp;31, 2003 Condensed
Balance Sheet data were derived from audited financial statements, but do not
include all disclosures required by generally accepted accounting principles.
These financial statements should be read in conjunction with the financial
statements and notes thereto contained in the Company&#146;s Annual Report on Form
10-K for the year ended December&nbsp;31, 2003.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right"><B>2.</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>Per Share Data</B></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>The Company&#146;s basic net income (loss)&nbsp;per share amounts have been computed by
dividing net income or loss by the weighted average number of shares of Common
Stock and Class&nbsp;A Stock outstanding. Diluted net income per share is based
upon the weighted average number of shares of Common Stock and Class&nbsp;A Stock
and the common stock equivalents outstanding when dilutive. Common stock
equivalents include: (i)&nbsp;outstanding stock options and restricted stock awards
under the Company&#146;s Long-Term Incentive Plans, which are included under the
treasury stock method when dilutive, and (ii)&nbsp;Common Stock to be issued under
the assumed conversion of the Company&#146;s outstanding convertible senior
subordinated notes, which are included under the if-converted method when
dilutive. For the three months ended March&nbsp;31, 2003, the Company reported a
net loss and, therefore, no common stock equivalents were included in the
computation of diluted net loss per share, since such inclusion would have been
antidilutive. The calculations of basic and diluted net income (loss)&nbsp;per
share are as follows:</TD>
</TR>

</TABLE>



<P align="center" style="font-size: 10pt">7
</DIV>

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<H5 align="left" style="page-break-before:always"><A HREF="#tocpage">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">




<P align="left" style="font-size: 10pt"><B>REGENERON PHARMACEUTICALS, INC.</B><BR>
<B>Notes to Condensed Financial Statements</B><BR>
<B><I>(Unless otherwise noted, dollars in thousands, except per share data)</I></B><BR>


<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="73%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="7"><B>Three Months Ended March 31,</B><HR size="1" noshade></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2004</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2003</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Income (loss) (Numerator):</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Net income (loss)&nbsp;for basic per share calculations</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">64,532</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">($</TD>
    <TD align="right">30,321</TD>
    <TD nowrap>)</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Adjustment for interest expense on Convertible
Notes</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,750</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Adjusted net income (loss)&nbsp;for diluted per
share calculations</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">67,282</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">($</TD>
    <TD align="right">30,321</TD>
    <TD nowrap>)</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Shares (Denominator):</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Weighted-average shares for basic per share
calculations</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">55,283</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">44,309</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Effect of stock options</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">1,663</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Effect of restricted stock awards</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">63</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Effect of convertible notes</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">6,611</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Adjusted weighted-average shares for diluted
per share calculations</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">63,620</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">44,309</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:20px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Basic net income (loss)&nbsp;per share</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">1.17</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">($</TD>
    <TD align="right">0.68</TD>
    <TD nowrap>)</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Diluted net income (loss)&nbsp;per share</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">1.06</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">($</TD>
    <TD align="right">0.68</TD>
    <TD nowrap>)</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>


<P align="left" style="font-size: 10pt">Shares issuable upon the exercise of stock options, vesting of restricted stock
awards, and conversion of convertible debt, which have been excluded from the
March&nbsp;31, 2004 and 2003 diluted per share amounts because their effect would
have been antidilutive, include the following:


<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="72%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="7"><B>Three months ended March 31,</B><HR size="1" noshade></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2004</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2003</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Stock Options:</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Weighted average number, in thousands</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">7,423</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">11,534</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Weighted average exercise price</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$&nbsp;&nbsp;</TD>

    <TD align="right">27.98</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">21.30</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Restricted Stock:</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Weighted average number, in thousands</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">178</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Convertible Debt:</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Weighted average number, in thousands</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">6,611</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Conversion price</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">30.25</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>




<P align="center" style="font-size: 10pt">8
</DIV>

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<P><HR noshade><P>
<H5 align="left" style="page-break-before:always"><A HREF="#tocpage">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">




<P align="left" style="font-size: 10pt"><B>REGENERON PHARMACEUTICALS, INC.</B><BR>
<B>Notes to Condensed Financial Statements</B><BR>
<B><I>(Unless otherwise noted, dollars in thousands, except per share data)</I></B><BR>



<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right"><B>3.</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>Stock-based Employee Compensation</B></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>The accompanying financial position and results of operations of the Company
have been prepared in accordance with APB Opinion No.&nbsp;25, <I>Accounting for Stock
Issued to Employees.</I></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>The following tables illustrate the effect on the Company&#146;s net income (loss)
and net income (loss)&nbsp;per share had compensation costs for the Company&#146;s
stock-based incentive plans been determined in accordance with the fair value
based method of accounting for stock-based compensation as prescribed by
Statement of Financial Accounting Standards No.&nbsp;123, <I>Accounting for Stock-Based
Compensation.</I></TD>
</TR>

</TABLE>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="70%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="6%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="7"><B>Three months ended March 31,</B><HR size="1" noshade></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2004</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2003</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Net income (loss), as reported</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">64,532</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">($</TD>
    <TD align="right">30,321</TD>
    <TD nowrap>)</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Add: Stock-based employee compensation
expense included in reported net income
(loss)</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">671</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">587</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Deduct: Total stock-based employee
compensation expense determined under
fair value based method for all awards</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(9,565</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">(</TD>
    <TD align="right">11,585</TD>
    <TD nowrap>)</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Pro forma net income (loss), basic</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">55,638</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">($</TD>
    <TD align="right">41,319</TD>
    <TD nowrap>)</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Pro forma net income (loss), diluted</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">58,388</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">($</TD>
    <TD align="right">41,319</TD>
    <TD nowrap>)</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Basic net income (loss)&nbsp;per share amounts:</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">As reported</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">1.17</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">($</TD>
    <TD align="right">0.68</TD>
    <TD nowrap>)</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Pro forma</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">1.01</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">($</TD>
    <TD align="right">0.93</TD>
    <TD nowrap>)</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Diluted net income (loss)&nbsp;per share amounts:</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">As reported</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">1.06</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">($</TD>
    <TD align="right">0.68</TD>
    <TD nowrap>)</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Pro forma</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">0.92</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">($</TD>
    <TD align="right">0.93</TD>
    <TD nowrap>)</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>



<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>For the purpose of the pro forma calculation, the fair value of each option
granted from the Company&#146;s stock-based incentive plans during the three months
ended March&nbsp;31, 2004 and 2003 was estimated on the date of grant using the
Black-Scholes option-pricing model. The weighted-average fair value of the
options granted during the three months ended March&nbsp;31, 2004 and 2003 was
$11.00 and $14.36, respectively. The following tables summarize the
assumptions used in computing the fair value of option grants.</TD>
</TR>

</TABLE>



<P align="center" style="font-size: 10pt">9
</DIV>

<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always"><A HREF="#tocpage">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">




<P align="left" style="font-size: 10pt"><B>REGENERON PHARMACEUTICALS, INC.</B><BR>
<B>Notes to Condensed Financial Statements</B><BR>
<B><I>(Unless otherwise noted, dollars in thousands, except per share data)</I></B><BR>


<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="50%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="9%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="10%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="9%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="10%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="7"><B>Three months ended March 31,</B><HR size="1" noshade></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2004</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2003</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">Expected volatility
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="right" valign="top">80%</TD>
    <TD nowrap valign="top"></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="right" valign="top">80%</TD>
    <TD nowrap valign="top"></TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">Expected lives
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap colspan="2" align="right" valign="top">5&nbsp;years
</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap colspan="2" align="right" valign="top">5&nbsp;years
</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">Dividend yield
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="right" valign="top">0%</TD>
    <TD nowrap valign="top"></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="right" valign="top">0%</TD>
    <TD nowrap valign="top"></TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">Risk-free interest rate
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="right" valign="top" nowrap>3.38%-4.19%</TD>
    <TD nowrap valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right" valign="top">&nbsp;</TD>
    <TD align="right" valign="top" nowrap>3.12%-4.01%</TD>
    <TD nowrap valign="top">&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>



<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Under the Regeneron Pharmaceuticals, Inc. 2000 Long-Term Incentive Plan, the
Company awards shares of restricted stock. Restrictions on these shares
generally lapse with respect to 25% of the shares every six months over
approximately a two-year period. In accordance with generally accepted
accounting principles, the Company records unearned compensation in
Stockholders&#146; Equity related to these awards. The amount is based on the fair
market value of shares of Common Stock on the grant date of the restricted
stock award and is expensed, on a pro rata basis, over the period that the
restrictions lapse. For the three months ended March&nbsp;31, 2004 and 2003, the
Company recognized compensation expense related to restricted stock awards of
$671 and $587, respectively.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right"><B>4.</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>Statement of Cash Flows</B></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Supplemental disclosure of noncash investing and financing activities:</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Included in accounts payable and accrued expenses at March&nbsp;31, 2004 and
December&nbsp;31, 2003 are $452 and $752, respectively, of accrued capital
expenditures. Included in accounts payable and accrued expenses at March&nbsp;31,
2003 and December&nbsp;31, 2002 are $1,702 and $13,490, respectively, of accrued
capital expenditures.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Included in accounts payable and accrued expenses at December&nbsp;31, 2003 and 2002
are $917 and $747, respectively, of accrued Company 401(k) Savings Plan
contribution expense. In the first quarter of both 2004 and 2003, the Company
contributed 64,333 and 42,543 shares, respectively, of Common Stock to the
401(k) Savings Plan in satisfaction of these obligations.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Included in marketable securities at March&nbsp;31, 2004 and December&nbsp;31, 2003 are
$1,023 and $878, respectively, of accrued interest income. Included in
marketable securities at March&nbsp;31, 2003 and December&nbsp;31, 2002 are $674 and
$2,013, respectively, of accrued interest income.</TD>
</TR>

</TABLE>



<P align="center" style="font-size: 10pt">10
</DIV>


<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always"><A HREF="#tocpage">Table of Contents</A></H5><P>
<DIV style="font-family: 'Times New Roman',Times,serif">


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>REGENERON PHARMACEUTICALS, INC.</B><BR><B>
Notes to Condensed Financial Statements </B><BR><B>
<I>(Unless otherwise noted, dollars in thousands, except per share
data)</I></B></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right"><B>5.</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>Accounts Receivable</B></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Accounts receivable as of March&nbsp;31, 2004 and December&nbsp;31, 2003 consist of the
following:</TD>
</TR>

</TABLE>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="75%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="74%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>March 31,</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>December 31,</B></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2004</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2003</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Receivable from Aventis Pharmaceuticals Inc.</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">13,738</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">8,917</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Receivable from Novartis Pharma AG</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">42,750</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">3,177</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Receivable from The Procter &#038; Gamble Company</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,665</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,670</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Receivable from Merck &#038; Co., Inc.</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">729</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">765</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">59,882</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">15,529</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>



<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right"><B>6.</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>Inventories</B></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Inventories consist of raw materials and other direct and indirect costs
associated with production of an intermediate for a Merck &#038; Co., Inc. (&#147;Merck&#148;)
pediatric vaccine under a long-term manufacturing agreement.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Inventories as of March&nbsp;31, 2004 and December&nbsp;31, 2003 consist of the
following:</TD>
</TR>

</TABLE>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="55%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="58%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="7%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="8%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="7%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="8%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>March 31,</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>December 31</B></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2004</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2003</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Raw materials</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">396</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">388</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Work-in-process</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">889</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">&#151;</TD>
    <TD nowrap><SUP>(1)</SUP></TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Finished products</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">7,813</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">8,618</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">9,098</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">9,006</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>



<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><SUP>(1)</SUP> Net of reserves of $195.</TD>
</TR>

</TABLE>


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right"><B>7.</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>Accounts Payable and Accrued Expenses</B></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Accounts payable and accrued expenses as of March&nbsp;31, 2004 and December
31, 2003 consist of the following:</TD>
</TR>

</TABLE>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="65%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="70%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>March 31,</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>December 31,</B></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2004</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2003</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Accounts payable</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">2,939</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">3,878</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Accrued payroll and related costs</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">4,698</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">5,125</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Accrued clinical trial expense</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">4,033</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">3,876</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Accrued expenses, other</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,235</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">3,762</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Interest payable on convertible notes</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">5,042</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,292</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">18,947</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">18,933</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>



<P align="center" style="font-size: 10pt">11
</DIV>

<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always"><A HREF="#tocpage">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>REGENERON PHARMACEUTICALS, INC.</B><BR><B>
Notes to Condensed Financial Statements </B><BR><B>
<I>(Unless otherwise noted, dollars in thousands, except per share data)</I></B></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right"><B>8.</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>Comprehensive Income (Loss)</B></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Comprehensive income (loss)&nbsp;represents the change in net assets of a
business enterprise during a period from transactions and other events and
circumstances from non-owner sources. Comprehensive income (loss)&nbsp;of the
Company includes net income (loss)&nbsp;adjusted for the change in net unrealized
gain on marketable securities. The net effect of income taxes on comprehensive
income (loss)&nbsp;is immaterial. For the three months ended March&nbsp;31, 2004 and
2003, the components of comprehensive income (loss)&nbsp;are:</TD>
</TR>

</TABLE>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="75%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="75%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="7"><B>Three months ended</B></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="7"><B>March 31,</B><HR size="1" noshade></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2004</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2003</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Net income (loss)</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">64,532</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">($30,321</TD>
    <TD nowrap>)</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Change in net unrealized gain on marketable securities</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">69</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(176</TD>
    <TD nowrap>)</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Total comprehensive income (loss)</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">64,601</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">($30,497</TD>
    <TD nowrap>)</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>



<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right"><B>9.</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>Collaboration Agreement &#150; Novartis Pharma AG</B></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>In March&nbsp;2003, the Company entered into a collaboration agreement with Novartis
Pharma AG (&#147;Novartis&#148;) to jointly develop and commercialize the Company&#146;s
Interleukin-1 Trap (&#147;IL-1 Trap&#148;). In connection with this agreement, Novartis
made a non-refundable up-front payment of $27.0&nbsp;million and purchased $48.0
million of newly issued unregistered shares of the Company&#146;s Common Stock.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Development expenses incurred in 2003 were shared equally by the Company and
Novartis. Regeneron funded its share of 2003 development expenses through
loans from Novartis. In March&nbsp;2004, Novartis forgave its outstanding loans to
Regeneron totaling $17.8&nbsp;million, including accrued interest, based on
Regeneron&#146;s achieving a pre-defined development milestone, which was recognized
as a research progress payment.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>In February&nbsp;2004, Novartis provided notice of its intention not to proceed with
the joint development of the IL-1 Trap. In March&nbsp;2004, Novartis agreed to pay
the Company $42.75&nbsp;million to satisfy its obligation to fund development costs
for the IL-1 Trap for the nine month period following its notification and for
the two months prior to that notice. The Company recorded the $42.75&nbsp;million
as other contract income in the first quarter of 2004. In addition, the
Company recognized contract research and development revenue of $22.1&nbsp;million
which represents the remaining amount of the March&nbsp;2003 up-front payment from
Novartis that had previously been deferred. Regeneron and Novartis each retain
rights under the collaboration agreement to elect to collaborate in the future
on the development and commercialization of certain other IL-1 antagonists.</TD>
</TR>

</TABLE>

<P align="center" style="font-size: 10pt">12
</DIV>

<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always"><A HREF="#tocpage">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">


<P><TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">



</TABLE>


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>REGENERON PHARMACEUTICALS, INC.</B><BR><B>
Notes to Condensed Financial Statements </B><BR><B>
<I>(Unless otherwise noted, dollars in thousands, except per share data)</I></B></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right"><B>10.</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>Segment Reporting</B></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>The Company&#146;s operations are managed in two business segments: research
and development, and contract manufacturing.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Research and development: Includes all activities related to the discovery of
potential therapeutics for human medical conditions, and the development and
commercialization of these discoveries. Also includes revenues and expenses
related to (i)&nbsp;the development of manufacturing processes prior to commencing
commercial production of a product under
contract manufacturing arrangements, and (ii)&nbsp;the supply of specified, ordered
research materials using Regeneron-developed proprietary technology.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Contract manufacturing: Includes all revenues and expenses related to the
commercial production of products under contract manufacturing arrangements.
The Company produces an intermediate for a Merck pediatric vaccine under a
long-term manufacturing agreement.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>The table below presents information about reported segments for the three
months ended March&nbsp;31, 2004 and 2003.</TD>
</TR>

</TABLE>




<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="75%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="38%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="8%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="8%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
</TR>

<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="15"><B>Three months ended March&nbsp;31, 2004<HR size="1" noshade></B></TD>
</TR>

<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Research &#038;</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Contract</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>&nbsp;</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>&nbsp;</B></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Development</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Manufacturing</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Reconciling Items</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Total</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Revenues</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">59,380</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">2,610</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">&#151;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">61,990</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Depreciation and
amortization</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">3,512</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">&#151;</TD>
    <TD nowrap><SUP>(1)</SUP></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">261</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">3,773</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Other contract income</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">42,750</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">42,750</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Interest expense</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">126</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">&#151;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">3,010</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">3,136</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Net income (loss)</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">66,033</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">385</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(1,886</TD>
    <TD nowrap>)<SUP>(2)</SUP></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">64,532</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Capital expenditures</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">685</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">&#151;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">&#151;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">685</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Total assets</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">133,931</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">12,665</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">359,582</TD>
    <TD nowrap><SUP>(3)</SUP></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">506,178</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>





<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="75%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="35%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="7%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="7%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
</TR>

<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="15"><B>Three months ended March&nbsp;31, 2003
<HR size="1" noshade></B></TD>
</TR>

<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Research &#038;</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Contract</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>&nbsp;</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>&nbsp;</B></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Development</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Manufacturing</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Reconciling Items</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Total</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Revenues</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">9,213</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">712</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">&#151;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">9,925</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Depreciation and
amortization</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,027</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">&#151;</TD>
    <TD nowrap><SUP>(1)</SUP></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">261</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,288</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Interest expense</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">&#151;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,937</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2,939</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Net (loss)&nbsp;income</DIV></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(28,638</TD>
    <TD nowrap>)</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">46</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(1,729</TD>
    <TD nowrap>)<SUP>(2)</SUP></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">(30,321</TD>
    <TD nowrap>)</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Capital expenditures</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">8,132</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">&#151;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">&#151;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">8,132</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Total assets</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">85,924</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">12,399</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="right">&nbsp;</TD>
    <TD align="right">332,118</TD>
    <TD nowrap><SUP>(3)</SUP></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">430,441</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>
<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">

    <TD width="3%" colspan="2"><sup>(1)</sup></TD>
    <TD>Depreciation and amortization related to contract manufacturing is
capitalized into inventory and included in contract manufacturing expense
when the product is shipped.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" colspan="2"><sup>(2)</sup></TD>
    <TD>Represents investment income, net of interest expense related to
convertible notes issued in October&nbsp;2001.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" colspan="2"><sup>(3)</sup></TD>
    <TD>Includes cash and cash equivalents, marketable securities, restricted
marketable securities, prepaid expenses and other current assets, and
other assets.</TD>
</TR>

</TABLE>



<P align="center" style="font-size: 10pt">13
</DIV>

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<DIV style="font-family: 'Times New Roman',Times,serif">


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>REGENERON PHARMACEUTICALS, INC.</B><BR><B>
Notes to Condensed Financial Statements </B><BR><B>
<I>(Unless otherwise noted, dollars in thousands, except per share data)</I></B></TD>
</TR>

</TABLE>




<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right"><B>11.</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>Legal Matters</B></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>In May&nbsp;2003, securities class action lawsuits were commenced against Regeneron
and certain of the Company&#146;s officers and directors in the United States
District Court for the Southern District of New York. A consolidated amended
class action complaint was filed in October&nbsp;2003. The
complaint, which purports to be brought on behalf of a class consisting of
investors in the Company&#146;s publicly traded securities between March&nbsp;28, 2000
and March&nbsp;30, 2003, alleges that the defendants misstated or omitted material
information concerning the safety and efficacy of AXOKINE, in violation of
Sections 10(b) and 20(a) of the Securities and Exchange Act of 1934 and Rule
10b-5 promulgated thereunder. Damages are sought in an unspecified amount.
The Company&#146;s management believes that the complaint is without merit, and in
December&nbsp;2003 the Company filed a motion to dismiss the lawsuit. The ultimate
outcome of this matter cannot presently be determined. Accordingly, no
provision for any liability that may result upon the resolution of this matter
has been made in the accompanying financial statements.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right"><B>12.</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>Future Impact of Recently Issued Accounting Standards</B></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>In April&nbsp;2004, the Emerging Issues Task Force issued Statement No.&nbsp;03-6,
<I>Participating Securities and the Two-Class&nbsp;Method under FASB Statement No.&nbsp;128,
Earnings per Share </I>(EITF 03-6). EITF 03-6 addresses a number of questions
regarding the computation of earnings per share (&#147;EPS&#148;) by companies that have
issued securities other than common stock that contractually entitle the holder
to participate in dividends and earnings of the company when, and if, it
declares dividends on its common stock. EITF 03-6 defines participation rights
based solely on whether the holder would be entitled to receive any dividends
if the entity declared them during the period and requires the use of the
two-class method for computing basic EPS when participating convertible
securities exist. In addition, EITF 03-6 expands the use of the two-class
method to encompass other forms of participating securities and is effective
for fiscal periods beginning after March&nbsp;31, 2004. The Company does not expect
the adoption of EITF 03-6 to have a material impact on the Company&#146;s financial
statements.</TD>
</TR>

</TABLE>

<P align="center" style="font-size: 10pt">14
</DIV>

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<DIV style="font-family: 'Times New Roman',Times,serif">


<P><TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">



</TABLE>

<DIV align="left">
<A name="108"></A>
</DIV>

<P align="left" style="font-size: 10pt"><B>Item&nbsp;2. Management&#146;s Discussion and Analysis of Financial Condition and
Results of Operations</B>



<P align="left" style="font-size: 10pt"><B>Overview</B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<I>The discussion below contains forward-looking statements that involve
risks and uncertainties relating to the future financial performance of
Regeneron Pharmaceuticals, Inc. and actual events or results may differ
materially. These statements concern, among other things, the possible success
and therapeutic applications of our product candidates and research programs,
the timing and nature of the clinical and research programs now underway or
planned, and the future sources and uses of capital and our financial needs.
These statements are made by us based on management&#146;s current beliefs and
judgment. In evaluating such statements, stockholders and potential investors
should specifically consider the various factors identified under the caption
&#147;Risk Factors&#148; which could cause actual results to differ materially from those
indicated by such forward-looking statements. We do not undertake any
obligation to update publicly any forward-looking statement, whether as a
result of new information, future events, or otherwise, except as required by
law.</I>


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Regeneron Pharmaceuticals, Inc. is a biopharmaceutical company that
discovers, develops, and intends to commercialize pharmaceutical products for
the treatment of serious medical conditions. Our clinical and preclinical
pipeline includes product candidates for the treatment of cancer, diseases of
the eye, rheumatoid arthritis and other inflammatory conditions, allergies,
asthma, obesity, and other diseases and disorders. Developing and
commercializing new medicines entails significant risk and expense. Since
inception we have not generated any sales or profits from the commercialization
of any of our product candidates.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Our core business strategy is to combine our strong foundation in basic
scientific research and discovery-enabling technology with our manufacturing
and clinical development capabilities to build a successful, integrated
biopharmaceutical company. Our efforts have yielded a diverse and growing
pipeline of product candidates that have the potential to address a variety of
unmet medical needs. We believe that our ability to develop product candidates
is enhanced by the application of our technology platforms. These platforms
are designed to discover specific genes of therapeutic interest for a
particular disease or cell type and validate targets through high-throughput
production of mammalian models. We continue to invest in the development of
enabling technologies to assist in our efforts to identify, develop, and
commercialize new product candidates.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Below is a summary of our clinical programs.

<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">
<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="3%" nowrap align="right">&#149;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>VEGF TRAP: </B>Protein-based product candidate designed to bind Vascular
Endothelial Growth Factor (called VEGF, also known as Vascular
Permeability Factor or VPF) and its relative, Placental Growth Factor
(called PlGF), and prevent their interaction with cell surface receptors.
VEGF (and to a less validated degree, PlGF) is required for the growth
of blood vessels that are needed for tumors to grow and is a potent
regulator of vascular permeability and leakage. In 2001, we initiated a
dose-escalation phase 1 clinical trial designed to assess the safety and
tolerability of the VEGF Trap in subjects with advanced solid tumor
malignancies. This trial is testing VEGF Trap delivered by
subcutaneous</TD>
</TR>
</TABLE>

<P align="center" style="font-size: 10pt">15
</DIV>

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<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="5%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>injection and is expected to be completed in the second quarter of 2004.
A second phase of this trial, which commenced in April&nbsp;2004, is testing
higher doses of the VEGF Trap delivered intravenously. This study will
evaluate the safety and tolerability of higher doses of the VEGF Trap and
will determine the pharmacokinetics of the molecule delivered
intravenously. We are also evaluating the VEGF Trap for the potential
treatment of certain eye diseases and in March&nbsp;2004, announced the
initiation of a phase 1 study of the VEGF Trap in patients with the
neovascular or &#147;wet&#148; form of age-related macular degeneration (called
AMD). This phase 1 trial is a randomized, placebo-controlled,
dose-escalating study designed to assess the safety and tolerability of
VEGF Trap in wet AMD and obtain a preliminary assessment of the potential
effect of the VEGF Trap on visual acuity.</TD>
</TR>

<TR>
    <TD>&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="5%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>In September&nbsp;2003, we entered into a collaboration agreement with Aventis
Pharmaceuticals Inc. to jointly develop and commercialize the VEGF Trap
in multiple oncology, ophthalmology, and possibly other indications
throughout the world with the exception of Japan, where product rights
remain with us. Under the collaboration agreement, agreed upon
development expenses incurred by both companies during the term of the
agreement will be funded by Aventis. If the collaboration becomes
profitable, we will reimburse Aventis for 50&nbsp;percent of the VEGF Trap development
expenses in accordance with a formula based on the amount of development
expenses and our share of the collaboration profits, or at a faster rate
at our option. In 2004, we and Aventis plan to invest approximately $100
million to support the development of the VEGF Trap. The broad based
development program will include multiple phase 1 studies to evaluate the
VEGF Trap in combination with other therapies in various cancer
indications, phase 2 single-agent studies of the VEGF Trap in separate
cancer indications, and multiple phase 1 studies of the VEGF Trap in
certain eye diseases.</TD>
</TR>

<TR>
    <TD>&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="5%" nowrap align="right">&#149;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>INTERLEUKIN-1 TRAP (IL-1 Trap): </B>Protein-based product candidate designed
to bind the interleukin-1 (called IL-1) cytokine and prevent its
interaction with cell surface receptors. IL-1 is thought to play an
important role in rheumatoid arthritis and other inflammatory diseases.
In October&nbsp;2003, we announced that the IL-1 Trap demonstrated evidence of
clinical activity and safety in patients with rheumatoid arthritis (RA)
in a phase 2 dose-ranging study in approximately 200 patients. Patients
treated with the highest dose, 100 milligrams of the IL-1 Trap, exhibited
non-statistically significant improvements in the proportion of American
College of Rheumatology (ACR)&nbsp;20 responses versus placebo, the primary
endpoint of the trial. Patients treated with the IL-1 Trap also
exhibited improvements in secondary endpoints of the trial. The IL-1
Trap was generally well tolerated and was not associated with any serious
drug-related adverse events.</TD>
</TR>

<TR>
    <TD>&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="5%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>On February&nbsp;27, 2004, we announced plans to initiate a phase 2b study of
the IL-1 Trap in patients with rheumatoid arthritis in the second half of
2004. The phase 2b study will be conducted in a larger patient
population, testing higher doses and for a longer period of time than in
the previous phase 2 trial. In addition, we intend to conduct studies of
the IL-1 Trap in a variety of other inflammatory diseases where
interleukin-1 is believed to play an important role. We are currently
working on new product formulations that</TD>
</TR>
</TABLE>

<P align="center" style="font-size: 10pt">16

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<DIV style="font-family: 'Times New Roman',Times,serif">


<P align="left" style="margin-left:6%; font-size: 10pt">would allow delivery of higher
doses of IL-1 Trap either through subcutaneous or intravenous
administration and plan to conduct patient tolerability studies later
this year.



<P align="left" style="margin-left:6%; font-size: 10pt">In March&nbsp;2003, we began collaborating with Novartis Pharma AG on the
development of the IL-1 Trap. On February&nbsp;27, 2004, Novartis provided
notice of its intention not to proceed with the joint development of the
IL-1 Trap. In March&nbsp;2004, Novartis agreed to pay us $42.75&nbsp;million to
satisfy its obligation to fund development costs for the nine month
period following its notification and for the two months prior to that
notice. Novartis paid us the $42.75&nbsp;million in April&nbsp;2004. All rights
to the IL-1 Trap have reverted to Regeneron. Novartis and we retain
rights under the collaboration agreement to elect to collaborate in the
future on the development and commercialization of certain other IL-1
antagonists. In March&nbsp;2004, we also achieved a pre-defined development
milestone and Novartis forgave all its outstanding loans to us totaling
$17.8&nbsp;million.


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="5%" nowrap align="right">&#149;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>INTERLEUKIN-4/INTERLEUKIN-13 TRAP (IL-4/13 Trap): </B>Protein-based
product candidate designed to bind both the interleukin-4 and
interleukin-13 (called IL-4 and IL-13) cytokines and prevent their
interaction with cell surface receptors. IL-4 and IL-13 are thought to
play a major role in diseases such as asthma, allergic disorders, and
other inflammatory diseases. In October&nbsp;2002, we initiated a phase 1
trial for the IL-4/13 Trap in adult subjects with mild to moderate asthma. This placebo-controlled,
double-blind, dose escalation study was designed to assess the safety and
tolerability of the IL-4/13 Trap. The trial was completed in the first
quarter of 2004 and we anticipate presenting the results at a scientific
conference in the second quarter of 2004. The IL-4/13 Trap was generally
safe and well tolerated at the doses tested in this phase 1 trial. We
are also evaluating the potential use of the IL-4/13 Trap in other
therapeutic indications.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="5%" nowrap align="right">&#149;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><B>AXOKINE</B><SUP><B>&#174;</B></SUP><B>: </B>Protein-based product candidate designed to act on the
brain region regulating appetite and energy expenditure. AXOKINE is
being developed for the treatment of obesity. In March&nbsp;2003, we
reported data from the 12-month treatment period of our initial phase 3
pivotal trial of AXOKINE. The double-blind treatment period in this
study was followed by a twelve-month open-label extension phase, during
which all study subjects received AXOKINE. The extension phase was
completed in the first quarter of 2004. We are currently conducting
research on improving the formulation and delivery of AXOKINE and
evaluating its commercial potential. We do not expect to initiate any
additional phase 3 clinical trials of AXOKINE in 2004.</TD>
</TR>

</TABLE>


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In addition to our clinical programs, we have research programs focused on
angiogenesis, metabolic diseases, muscle atrophy and related disorders,
inflammatory conditions, and other diseases and disorders. We also use our
Velocigene&#174; and Trap technology platforms to discover and develop new product
candidates and are developing our Velocimmune&#153; platform to create fully
human, therapeutic antibodies.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Developing and commercializing new medicines entails significant risk and
expense. Since inception we have not generated any sales or profits from the
commercialization of any of our product candidates and may never receive such
revenues. Before revenues from the commercialization of our product candidates
can be realized, we (or our collaborators) must overcome a number of hurdles
which include successfully completing research and development and obtaining
regulatory approval from the U.S. Food and Drug Administration (or FDA) and


<P align="center" style="font-size: 10pt">17
</DIV>

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<DIV style="font-family: 'Times New Roman',Times,serif">

<P align="left" style="margin-left: 0%; text-indent: 0%; margin-right: 0%; font-size: 10pt">regulatory authorities in other countries. In addition, the biotechnology and
pharmaceutical industries are rapidly evolving and highly competitive, and new
developments may render our products and technologies uncompetitive or
obsolete.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;From inception on January&nbsp;8, 1988 through March&nbsp;31, 2004, we had a
cumulative loss of $467.0&nbsp;million. In the absence of revenues from the
commercialization of our product candidates or other sources, the amount,
timing, nature, or source of which cannot be predicted, our losses will
continue as we conduct our research and development activities. We expect to
incur substantial losses over the next several years as we continue the
clinical development of the VEGF Trap, IL-1 Trap, IL-4/13 Trap, and AXOKINE;
commercialize product candidates that receive regulatory approval, if any;
advance new product candidates into clinical development from our existing
research programs; and continue our research and development programs.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Our activities may expand over time and may require additional resources,
and we expect our operating losses to be substantial over at least the next
several years. Our losses may fluctuate from quarter to quarter and will
depend, among other factors, on the progress of our research and development
efforts, the timing of certain expenses, and the amount and timing of payments
that we receive from collaborators.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The planning, execution, and results of our clinical programs are
significant factors that can affect our operating and financial results. In
our four clinical programs, key first quarter 2004 clinical events and plans
for the remainder of 2004 are as follows:

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="85%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="15%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="26%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="41%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD nowrap align="left"><B>Product Candidate</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>First Quarter 2004 Events</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Additional 2004 Plans</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">VEGF Trap
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right" valign="top">&#149;<BR><BR>
<BR>
<BR>

&#149;
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Continued phase 1<BR>
subcutaneous<BR>
single-agent trial in<BR>
cancer<BR>
Commenced phase 1<BR>
trial in neovascular<BR>
age-related macular<BR>
degeneration
</TD>
    <TD>&nbsp;</TD>
    <TD align="right" valign="top">&#149;<BR>
<BR>
&#149;<BR>
<BR>
&#149;<BR><BR>
&#149;<BR>
<BR>
&#149;

</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Complete phase 1 subcutaneous single-agent
trial in cancer<BR>
Conduct phase 1 intravenous single-agent trial in cancer<BR>
Commence phase 2 single-agent trials in<BR>
specific cancer indications<BR>
Commence several phase 1 combination therapy trials in cancer<BR>
Commence multiple phase 1<BR>
trials in eye diseases</TD>
</TR>

<TR>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD nowrap align="center" colspan="9"><HR size="1" noshade></TD>
</TR>


<TR valign="top">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">IL-1 Trap
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right" valign="top">&#149;
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Planned for phase 2b<BR>
trial in rheumatoid<BR>
arthritis
</TD>
    <TD>&nbsp;</TD>
    <TD align="right" valign="top">&#149;<BR>
&nbsp;<BR>&#149;<BR>
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Commence phase 2b trial in<BR>
rheumatoid arthritis<BR>
Commence phase 1 trial in<BR>
other indications</TD>
</TR>


<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right" valign="top">&#149;
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Evaluate IL-1 Trap in other<BR>
inflammatory conditions</TD>
</TR>

<TR>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD nowrap align="center" colspan="9"><HR size="1" noshade></TD>
</TR>


<TR valign="top">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">IL-4/13 Trap
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right" valign="top">&#149;
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Completed phase 1<BR>
trial in asthma
</TD>
    <TD>&nbsp;</TD>
    <TD align="right" valign="top">&#149;
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Plan for phase 2 trial in<BR>
asthma</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>



<P align="center" style="font-size: 10pt">18
</DIV>

<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always"><A HREF="#tocpage">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="85%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="15%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="26%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="41%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD nowrap align="left"><B>Product Candidate</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>First Quarter 2004 Events</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Additional 2004 Plans</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">AXOKINE
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right" valign="top">&#149;<BR>
<BR>

&#149;
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Completed safety
extension portion of
phase 3 trial<BR>

Completed intermittent
treatment trials
</TD>
    <TD>&nbsp;</TD>
    <TD align="right" valign="top">&#149;<BR><BR>

&#149;
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Additional development and
market research activities
<BR>
No new phase 3 trials
planned</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>

<HR noshade width="85%" size="1">

<P align="left" style="font-size: 10pt"><B>Results of Operations</B>



<P align="left" style="font-size: 10pt"><B><I>Three Months Ended March&nbsp;31, 2004 and 2003</I></B>



<P align="left" style="font-size: 10pt"><I>Revenues:</I>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Revenues in the three months ended March&nbsp;31, 2004 and 2003 consist of the
following:

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="65%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="82%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="7"><B>(In millions)</B><HR size="1" noshade></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2004</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>2003</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Contract research &#038; development revenue
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Aventis</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">16.4</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">&#151;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Novartis</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">22.1</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">6.5</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Procter &#038; Gamble</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2.7</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2.6</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:20px; text-indent:-10px">Other</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">0.4</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">0.1</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Total contract research &#038; development revenue</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">41.6</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">9.2</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Research progress payment</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">17.8</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">&#151;</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Contract manufacturing revenue</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2.6</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">0.7</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:30px; text-indent:-10px">Total revenue</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">62.0</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">9.9</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Our total revenue increased to $62.0&nbsp;million in the first quarter of 2004
from $9.9&nbsp;million for the same period in 2003 primarily from revenue related to
our collaboration with Aventis on the VEGF Trap, which commenced in September
2003, and our collaboration with Novartis on the IL-1 Trap, which commenced in
March&nbsp;2003. Contract research and development revenue from collaborators for
the first quarter of 2004, as detailed below, consists partly of reimbursement
for research and development expenses and partly of the recognition of revenue
related to non-refundable, up-front payments. Non-refundable, up-front
payments are recorded as deferred revenue and recognized ratably over the
period over which we are obligated to perform services in accordance with Staff
Accounting Bulletin No.&nbsp;104, <I>Revenue Recognition </I>(SAB 104). In the first
quarter of 2004, Novartis provided notice of its intention not to proceed with
the joint development of the IL-1 Trap and the remaining balance of the March
2003 $27.0&nbsp;million up-front payment from Novartis was recognized as contract research and
development revenue.


<P align="center" style="font-size: 10pt">19
</DIV>

<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always"><A HREF="#tocpage">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">




<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="65%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="22%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="6%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="6%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="4%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
</TR>

<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="19"><B>For the three months
ended March&nbsp;31, 2004<BR>
(In millions)</B><HR size="1" noshade></TD>
</TR>

<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="11"><B>Up-front Payment</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>&nbsp;</B></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Total</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Revenue</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Deferred</B></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Total</B></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Original</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Recognized</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Revenue at</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Expense</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Revenue</B></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Payment</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>in Quarter</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>March 31, 2004</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Reimbursement</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="3"><B>Recognized</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="background: #eeeeee">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Aventis</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">80.0</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">2.7</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">73.6</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">13.7</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">16.4</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">Novartis</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">27.0</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">22.1</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">22.1</TD>
    <TD>&nbsp;</TD>
</TR>

<TR valign="bottom" style="background: #eeeeee">
    <TD nowrap><DIV style="margin-left:10px; text-indent:-10px">Procter &#038;
Gamble</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2.7</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">2.7</TD>
    <TD>&nbsp;</TD>
</TR>

<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="1" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">107.0</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">24.8</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">73.6</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">16.4</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right">$</TD>
    <TD align="right">41.2</TD>
    <TD>&nbsp;</TD>
</TR>
<TR style="font-size: 1px">
    <TD><DIV style="margin-left:10px; text-indent:-10px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="right"><HR size="4" noshade>&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In the first quarter of 2003 we recognized $5.1&nbsp;million in revenue related
to the reimbursement of research and development expenses by Novartis and $1.4
million in revenue related to the $27.0&nbsp;million, up-front payment made in March 2003.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In March&nbsp;2004, Novartis forgave all its outstanding loans, including
accrued interest, to Regeneron totaling $17.8&nbsp;million, based upon Regeneron&#146;s
achieving a pre-defined development milestone, which was recognized as a
research progress payment.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Contract manufacturing revenue relates primarily to our long-term
agreement with Merck, which expires in October of 2005, unless extended by
mutual agreement, to manufacture a vaccine intermediate at our Rensselaer, New
York facility. Contract manufacturing revenue increased to $2.6&nbsp;million in the
first quarter of 2004 from $0.7&nbsp;million for the same period in 2003 because we
shipped more product to Merck. Revenue and the related manufacturing expense
are recognized as product is shipped, after acceptance by Merck. Included in
contract manufacturing revenue in the first three months of 2004 was $0.5
million of deferred revenue associated with capital improvement reimbursements
paid by Merck prior to commencement of production. This deferred revenue is
being recognized as product is shipped to Merck based on the total amount of
product expected to be shipped over the life of the agreement.


<P align="left" style="font-size: 10pt"><I>Research and Development Expenses:</I>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Research and development (R&#038;D) expenses decreased to $32.2&nbsp;million in the
first quarter of 2004 from $34.4&nbsp;million in 2003, due primarily to (i)&nbsp;a $4.2
million decrease in clinical trial expenses associated primarily with the
completion of the double-blind treatment portion of our AXOKINE phase 3
clinical trial for the treatment of obesity in the first quarter of 2003 and
the completion of our IL-1 Trap phase 2 clinical trial for the treatment of
rheumatoid arthritis in the third quarter of 2003 and (ii)&nbsp;a $1.0&nbsp;million
decrease in lab supply, outside testing, and research contract expenses. These
decreases were offset by a $3.0&nbsp;million increase in other R&#038;D expenses,
primarily facility expenses at our expanded Rensselaer facility such as rent,
utilities, insurance, and depreciation.


<P align="center" style="font-size: 10pt">20
</DIV>

<!-- PAGEBREAK -->
<P><HR noshade><P>
<H5 align="left" style="page-break-before:always"><A HREF="#tocpage">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">

<P align="left" style="font-size: 10pt"><I>Contract Manufacturing Expenses:</I>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Contract manufacturing expenses increased to $2.2&nbsp;million in the first
quarter of 2004, compared to $0.7&nbsp;million in the same period in 2003, primarily
because we shipped more product to Merck.


<P align="left" style="font-size: 10pt"><I>General and Administrative Expenses:</I>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;General and administrative expenses increased to $3.8&nbsp;million in the first
quarter of 2004 from $3.5&nbsp;million in the same period of 2003, due primarily to
increases in professional fees.


<P align="left" style="font-size: 10pt"><I>Other Income and Expense:</I>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In the first quarter of 2004, Novartis notified us of its decision to
forgo its right under the collaboration to jointly develop the IL-1 Trap and
agreed to pay us $42.75&nbsp;million to satisfy its obligation to fund development
costs for the IL-1 Trap for the nine-month period following its notification
and for the two months prior to that notice. The $42.75&nbsp;million was included
in other contract income in the first quarter of 2004.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Interest expense is attributable principally to $200.0&nbsp;million of
convertible notes issued in October&nbsp;2001, which mature in 2008 and bear
interest at 5.5% per annum. Investment income
decreased to $1.1&nbsp;million in 2004 from $1.2&nbsp;million in 2003 due to lower
effective interest rates on investment securities. Interest expense increased
to $3.1&nbsp;million in the first quarter of 2004 from $2.9&nbsp;million in the same
period of 2003 primarily because of interest on loans from Novartis to fund our
share of 2003 IL-1 Trap development costs. (These Novartis loans were forgiven
in March&nbsp;2004 as described above.)


<P align="left" style="font-size: 10pt"><B>Liquidity and Capital Resources</B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Since our inception in 1988, we have financed our operations primarily
through offerings of our equity securities, a private placement of convertible
debt, revenue earned under our agreements with Aventis, Novartis, Merck,
Procter &#038; Gamble, Serono, and other companies, and investment income.


<P align="left" style="font-size: 10pt"><B><I>Three Months Ended March&nbsp;31, 2004 and 2003</I></B>



<P align="left" style="font-size: 10pt"><I>Cash (Used in) Provided by Operations:</I>



<P align="left" style="margin-left: 0%; text-indent: 0%; margin-right: 0%; font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;At March&nbsp;31, 2004, we had $351.4&nbsp;million in cash, cash equivalents,
marketable securities, and restricted marketable securities. Restricted
marketable securities are pledged U.S. government securities which will be
sufficient upon receipt of scheduled principal and interest payments to provide
for the payment in full of the interest payments on the convertible senior
subordinated notes through 2004. In the first quarter of 2004, our net income
was $64.5&nbsp;million but we used $18.6&nbsp;million of cash in operations.
The difference between net income and cash usage was primarily due
to the above-described $42.75&nbsp;million of other contract income, which was
receivable from Novartis at the end of the first quarter (and paid in April
2004) and the recognition of $39.9&nbsp;million of non-cash deferred and


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<P align="left" style="margin-left: 0%; text-indent: 0%; margin-right: 0%; font-size: 10pt">research progress payment revenue related to Novartis. In the first quarter of 2003,
our net loss was $30.3&nbsp;million but we provided $1.2&nbsp;million of cash from
operations, principally due to the receipt of a $27.0&nbsp;million non-refundable,
up-front payment from Novartis in the first quarter of 2003, of which only $1.4
million was recognized as revenue during the quarter


<P align="left" style="font-size: 10pt"><I>Cash Provided by Investing Activities:</I>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Net cash provided by investing activities was $70.2&nbsp;million in the first
quarter of 2004 compared to $61.8&nbsp;million in the same period in 2003. The
increase is due primarily to a decrease in payments for capital expenditures
(resulting from the completion of the Rensselaer plant expansion in 2003)
partially offset by lower cash proceeds from sales or maturities of investment
securities.


<P align="left" style="font-size: 10pt"><I>Cash Provided by Financing Activities:</I>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Cash provided by financing activities decreased to $4.1&nbsp;million in the
first quarter of 2004 compared to $48.5&nbsp;million in the same period in 2003. In
March&nbsp;2003, we sold $48.0&nbsp;million of newly issued unregistered shares of our
Common Stock to Novartis in connection with our collaboration agreement.


<P align="left" style="font-size: 10pt"><B><I>Aventis Agreement:</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Under the collaboration agreement with Aventis, we and Aventis will share
co-promotion rights and profits on sales, if any, of the VEGF Trap. Aventis
has agreed to make a $25.0&nbsp;million payment to us upon achievement of an
early-stage clinical milestone. We may also receive up to $360.0&nbsp;million in
additional milestone payments upon receipt of specified marketing approvals for
up to eight VEGF Trap indications in Europe or the United States.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We have agreed to continue to manufacture clinical supplies of the VEGF
Trap at our plant in Rensselaer, New York. Aventis has agreed to be
responsible for providing commercial scale manufacturing capacity for the VEGF
Trap. Under the collaboration agreement, agreed upon development expenses
incurred by both companies during the term of the agreement, including costs
associated with the manufacture of clinical drug supply, will be funded by
Aventis. If the collaboration becomes profitable, we will reimburse Aventis
for 50&nbsp;percent of the VEGF Trap development expenses in accordance with a
formula based on the amount of development expenses and our share of the
collaboration profits, or at a faster rate at our option. We have the option
to conduct additional pre-phase 3 studies at our own expense.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In 2004, we and Aventis plan to invest approximately $100&nbsp;million to
support the development of the VEGF Trap. The broad based development program
will include multiple phase 1 studies to evaluate the VEGF Trap in combination
with other therapies in various cancer indications, phase 2 single-agent
studies of the VEGF Trap in separate cancer indications, and multiple phase 1
studies of the VEGF Trap in certain eye diseases.


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<P align="left" style="font-size: 10pt"><B><I>Capital Expenditures:</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Our additions to property, plant, and equipment totaled $0.7&nbsp;million and
$8.1&nbsp;million for the first three months of 2004 and 2003, respectively. During
the remainder of 2004, we expect to incur approximately $5&nbsp;million to $8
million in capital expenditures which primarily consists of equipment for our
expanded manufacturing, research, and development activities.


<P align="left" style="font-size: 10pt"><B><I>Funding Requirements:</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We expect to continue to incur substantial funding requirements primarily
for research and development activities (including preclinical and clinical
testing). We currently anticipate that for the remainder of 2004 approximately
50-70% of our expenditures will be directed toward the preclinical and clinical
development of product candidates, including the VEGF Trap, IL-1 Trap, IL-4/13
Trap, and AXOKINE; approximately 10-20% of our expenditures will cover our
basic research activities and the continued development of our novel technology
platforms; and the remainder of our expenditures will be for capital
expenditures and general corporate purposes, including working capital.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The amount we need to fund operations will depend on various factors,
including the status of competitive products, the success of our research and
development programs, the potential
future need to expand our professional and support staff and facilities,
the status of patents and other intellectual property rights, the delay or
failure of a clinical trial of any of our potential drug candidates, and the
continuation, extent, and success of any collaborative research and development
collaborations (including those with Aventis and Procter &#038; Gamble). Clinical
trial costs are dependent, among other things, on the size and duration of
trials, fees charged for services provided by clinical trial investigators and
other third parties, the costs for manufacturing the product candidate for use
in the trials, supplies, laboratory tests, and other expenses. The amount of
funding that will be required for our clinical programs depends upon the
results of our research and preclinical programs and early-stage clinical
trials, regulatory requirements, the clinical trials underway plus additional
clinical trials that we decide to initiate, and the various factors that affect
the cost of each trial as described above. In the future, if we are able to
successfully develop, market, and sell certain of our product candidates, we
may be required to pay royalties or otherwise share the profits generated on
such sales in connection with our collaboration and licensing agreements.
Also, under the terms of the Aventis collaboration agreement, if the
collaboration becomes profitable, we will reimburse Aventis for 50&nbsp;percent of
the VEGF Trap development expenses in accordance with a formula based on the
amount of development expenses and our share of the collaboration profits, or
at a faster rate at our option.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We expect that expenses related to the filing, prosecution, defense, and
enforcement of patent and other intellectual property claims will continue to
be substantial as a result of patent filings and prosecutions in the United
States and foreign countries.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We believe that our existing capital resources will enable us to meet
operating needs through at least the end of 2005 and expect to end 2004 with a
cash balance of $300 to $325&nbsp;million. However, this is a forward-looking
statement based on our current operating plan, and there may be a change in
projected revenues or expenses that would lead to our capital being consumed


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<P align="left" style="margin-left: 0%; text-indent: 0%; margin-right: 0%; font-size: 10pt">significantly before such time. If there is insufficient capital to fund all
of our planned operations and activities, we believe we would prioritize
available capital to fund preclinical and clinical development of our product
candidates. We have no off-balance sheet arrangements and do not guarantee the
obligations of any other entity. As of March&nbsp;31, 2004, we had no established
banking arrangements through which we could obtain short-term financing or a
line of credit. In the event we need additional financing for the operation
of our business, we will consider collaborative arrangements and additional
public or private financing, including additional equity financing. Factors
influencing the availability of additional financing include our progress in
product development, investor perception of our prospects, and the general
condition of the financial markets. We may not be able to secure the necessary
funding through new collaborative arrangements or additional public or private
offerings. If we cannot raise adequate funds to satisfy our capital
requirements, we may have to delay, scale-back, or eliminate certain of our
research and development activities or future operations. This could harm our
business.


<P align="left" style="font-size: 10pt"><B>Future Impact of Recently Issued Accounting Standards</B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In April&nbsp;2004, the Emerging Issues Task Force issued Statement No.&nbsp;03-6,
<I>Participating Securities and the Two-Class&nbsp;Method under FASB Statement No.&nbsp;128,
Earnings per Share </I>(EITF 03-6). EITF 03-6 addresses a number of questions
regarding the computation of earnings per share (EPS)&nbsp;by companies that have
issued securities other than common stock that contractually entitle the holder
to participate in dividends and earnings of the company when, and if, it
declares
dividends on its common stock. EITF 03-6 defines participation rights
based solely on whether the holder would be entitled to receive any dividends
if the entity declared them during the period and requires the use of the
two-class method for computing basic EPS when participating convertible
securities exist. In addition, EITF 03-6 expands the use of the two-class
method to encompass other forms of participating securities and is effective
for fiscal periods beginning after March&nbsp;31, 2004. We do not expect the
adoption of EITF 03-6 to have a material impact on our financial statements.


<P align="left" style="font-size: 10pt"><B>Risk Factors</B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We operate in an environment that involves a number of significant risks
and uncertainties. We caution you to read the following risk factors, which
have affected, and/or in the future could affect, our business, operating
results, financial condition, and cash flows. The risks described below
include forward-looking statements, and our actual results may differ
substantially from those discussed in these forward-looking statements.
Additional risks and uncertainties not currently known to us or that we
currently deem immaterial may also impair our business operations.
Furthermore, additional risks and uncertainties are included under other
captions in this report and in our Annual Report on Form&nbsp;10-K and should be considered by our investors.


<P align="left" style="font-size: 10pt"><B>Risks Related to our Financial Results and Need for Additional Financing</B>



<P align="left" style="margin-left: 0%; text-indent: 0%; margin-right: 0%; font-size: 10pt"><B><I>We have had a history of operating losses and we may never achieve
profitability. If we continue to incur operating losses, we may be unable to
continue our operations.</I></B>


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;From inception on January&nbsp;8, 1988 through March&nbsp;31, 2004, we had a
cumulative loss of $467.0&nbsp;million. If we continue to incur operating losses
and fail to become a profitable company,


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<P align="left" style="margin-left: 0%; text-indent: 0%; margin-right: 0%; font-size: 10pt">we may be unable to continue our
operations. We have no products that are available for sale and do not know
when we will have products available for sale, if ever. In the absence of
revenue from the sale of products or other sources, the amount, timing, nature,
or source of which cannot be predicted, our losses will continue as we conduct
our research and development activities.


<P align="left" style="margin-left: 0%; text-indent: 0%; margin-right: 0%; font-size: 10pt"><B><I>We will need additional funding in the future, which may not be available to
us, and which would then force us to delay, reduce, or eliminate our product
development programs or commercialization efforts.</I></B>


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We will need to expend substantial resources for research and development,
including costs associated with clinical testing of our product candidates. We
believe our existing capital resources will enable us to meet operating needs
through at least the end of 2005. However, our projected revenue may decrease
or our expenses may increase and that would lead to our capital being consumed
significantly before such time. We will likely require additional financing in
the future and we may not be able to raise such additional funds. If we are
able to obtain additional financing through the sale of equity or convertible
debt securities, such sales may be dilutive to our shareholders. Debt
financing arrangements may require us to pledge certain assets or enter into
covenants that would restrict certain business activities or our ability to
incur further indebtedness and may contain other terms that are not favorable
to our shareholders. If we are unable to raise sufficient funds to complete
the development of our product candidates, we may
face delay, reduction, or elimination of our research and development
programs or preclinical or clinical trials, in which case our business,
financial condition, or results of operations may be materially harmed.


<P align="left" style="margin-left: 0%; text-indent: 0%; margin-right: 0%; font-size: 10pt"><B><I>We have a significant amount of debt and may have insufficient cash to satisfy
our debt service and repayment obligations. In addition, the amount of our
debt could impede our operations and flexibility.</I></B>


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We have a significant amount of convertible debt and semi-annual interest
payment obligations. This debt, unless converted to shares of our Common
Stock, will mature in October&nbsp;2008. We may be unable to generate sufficient
cash flow or otherwise obtain funds necessary to make required payments on our
debt. Even if we are able to meet our debt service obligations, the amount of
debt we already have could hurt our ability to obtain any necessary financing
in the future for working capital, capital expenditures, debt service
requirements, or other purposes. In addition, our debt obligations could
require us to use a substantial portion of cash to pay principal and interest
on our debt, instead of applying those funds to other purposes, such as
research and development, working capital, and capital expenditures.


<P align="left" style="font-size: 10pt"><B>Risks Related to Development of our Product Candidates</B>



<P align="left" style="font-size: 10pt"><B><I>Successful development of any of our product candidates is highly uncertain.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Only a small minority of all research and development programs ultimately
result in commercially successful drugs. We have never developed a drug that
has been approved for marketing and sale and we may never succeed in developing
an approved drug. Even if clinical



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<P align="left" style="font-size: 10pt">trials demonstrate safety and effectiveness of any of our product
candidates for a specific disease and the necessary regulatory approvals are
obtained, the commercial success of any of our product candidates will depend
upon their acceptance by patients, the medical community, and third-party
payors and on our and our partners&#146; ability to successfully manufacture and
commercialize our product candidates. Our product candidates are delivered
either by intravenous or subcutaneous injections, which are generally less well
received by patients than tablet or capsule delivery. If our products are not
successfully commercialized, we will not be able to recover the significant
investment we have made in developing such products and our business would be
severely harmed.


<P align="left" style="font-size: 10pt"><B><I>Clinical trials required for our product candidates are expensive and
time-consuming, and their outcome is highly uncertain. If any of our drug
trials are delayed or achieve unfavorable results, we will have to delay or may
be unable to obtain regulatory approval for our product candidates.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We must conduct extensive testing of our product candidates before we can
obtain regulatory approval to market and sell them. We need to conduct both
preclinical animal testing and human clinical trials. Conducting these trials
is a lengthy, time-consuming, and expensive process. These tests and trials
may not achieve favorable results for many reasons, including, among others,
failure of the product candidate to demonstrate safety or efficacy, the
development of serious or life-threatening adverse events (or side effects)
caused by or connected with exposure to the product candidate, difficulty in
enrolling and maintaining subjects in the clinical trial, lack of sufficient
supplies of the product candidate, and the failure of clinical investigators,
trial monitors and other consultants, or trial subjects to comply with the
trial plan or protocol. A clinical trial may also fail because it did not
include a sufficient number of patients to detect the endpoint being measured
or reach statistical significance. For example, the pending trials studying
the maintenance of weight loss following short-term treatment regimens with
AXOKINE may not have enrolled a sufficient number of patients to detect
statistically significant differences between patients treated with AXOKINE and
those taking placebo. These trials were designed before we had access to the
data from the completed pivotal phase 3 AXOKINE trial, which demonstrated that
the magnitude of the average difference in weight loss observed between all
AXOKINE-treated subjects and those taking placebo was small.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We will need to reevaluate any drug candidate that does not test favorably
and either conduct new trials, which are expensive and time consuming, or
abandon the drug development program. Even if we obtain positive results from
preclinical or clinical trials, we may not achieve the same success in future
trials. Many companies in the biopharmaceutical industry, including us, have
suffered significant setbacks in clinical trials, even after promising results
have been obtained in earlier trials. The failure of clinical trials to
demonstrate safety and effectiveness for our desired indications could harm the
development of the product candidate, and our business, financial condition,
and results of operations may be materially harmed.

<P align="left" style="font-size: 10pt"><B><I>The development of serious or life-threatening side effects with any of our
product candidates would lead to delay or discontinuation of development, which
could severely harm our business.</I></B>



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<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;During the conduct of clinical trials, patients report changes in their
health, including illnesses, injuries, and discomforts to their study doctor.
Often, it is not possible to determine whether or not the drug candidate being
studied caused these conditions. Various illnesses, injuries, and discomforts
have been reported from time-to-time during clinical trials of our product
candidates. Although our current drug candidates appeared to be generally well
tolerated in clinical trials, it is possible as we test any of them in larger,
longer, and more extensive clinical programs, illnesses, injuries, and
discomforts that were observed in earlier trials, as well as conditions that
did not occur or went undetected in smaller previous trials, will be reported
by patients. If additional clinical experience indicates that any of our
product candidates has many side effects or causes serious or life-threatening
side effects, the development of the product candidate may fail or be delayed,
which would severely harm our business.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Our VEGF Trap is being studied for the potential treatment of certain
types of cancer and diseases of the eye. There are many potential safety
concerns associated with significant blockade of vascular endothelial growth
factor, or VEGF. These safety concerns may limit our ability to successfully
develop the VEGF Trap.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Genentech and Eyetech are developing VEGF inhibiting molecules for certain
diseases of the eye that will be delivered by direct administration to the eye.
We are studying the VEGF Trap for the potential treatment of certain diseases
of the eye through intravitreal injections in the eye or general administration
through intravenous infusions or subcutaneous injections. Although we believe
that there are potential clinical advantages to general administration over
injections directly in the eye (including patient comfort and acceptance),
there are unique potential risks to patients associated with systemic blockade
of VEGF by intravenous infusions or subcutaneous injections that could limit or
end the VEGF Trap development program. These risks, based on the clinical and
preclinical experience of systemically delivered VEGF inhibitors, include
bleeding, hypertension, and proteinuria. In addition, patients given infusions
of any protein, including the VEGF Trap, may develop severe hypersensitivity
reactions, referred to as infusion reactions. There may be additional
complications or side effects that could harm the development of the VEGF Trap
for either the treatment of cancer or diseases of the eye.

<P align="left" style="font-size: 10pt"><B><I>Our product candidates in development are recombinant proteins that could cause
an immune response, resulting in the creation of harmful or neutralizing
antibodies against the therapeutic protein.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In addition to the safety, efficacy, manufacturing, and regulatory hurdles
faced by our product candidates, the administration of recombinant proteins
frequently causes an immune response, resulting in the creation of antibodies
against the therapeutic protein. The antibodies can have no effect or can
totally neutralize the effectiveness of the protein, or require that higher
doses be used to obtain a therapeutic effect. In some cases, the antibody can
cross react with the patient&#146;s own proteins, resulting in an &#147;auto-immune&#148; type
disease. Whether antibodies will be created can often not be predicted from
preclinical or clinical experiments, and their appearance is often delayed, so
that there can be no assurance that neutralizing antibodies will not be created
at a later date &#150; in some cases even after pivotal clinical trials have been
completed. Approximately two-thirds of the subjects who received AXOKINE in
the completed phase 3 study developed neutralizing antibodies. In addition,
subjects who received the IL-1 Trap in clinical trials have developed
antibodies. It is possible that as we test the VEGF Trap in different patient


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<P align="left" style="font-size: 10pt">populations and larger clinical trials, subjects given the VEGF Trap will
develop antibodies to the product candidate.


<P align="left" style="font-size: 10pt"><B><I>A previous phase 3 study evaluating AXOKINE demonstrated modest average weight
loss over a 12-month period. In addition, a completed phase 2 study evaluating
the IL-1 Trap in patients with rheumatoid arthritis failed to achieve its
primary endpoint.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In March&nbsp;2003, we reported data from the 12-month treatment period of our
initial phase 3 pivotal trial of AXOKINE. Although the phase 3 study met its
primary endpoints and many individuals achieved a medically meaningful weight
loss, the average weight loss was small and limited by the development of
antibodies.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In October&nbsp;2003, we reported results from the first phase 2 trial of our
IL-1 Trap. While patients treated with the highest dose, 100 milligrams of the
IL-1 Trap once a week, exhibited improvements in the primary endpoint of the
trial, the proportion of ACR 20 responses versus placebo, the results did not
achieve statistical significance. We plan to conduct a phase 2b study of the
IL-1 Trap in a larger patient population, testing higher doses than were tested
in the previous phase 2 trial and for a longer period of time. However, higher
doses may not lead to better results than were demonstrated in the previous
phase 2 trial. In addition, safety or tolerability concerns may arise which
limit our ability to deliver higher doses of the IL-1 Trap to patients. We
plan to study higher doses of the IL-1 Trap through increased subcutaneous
injections and intravenous delivery. Either approach may affect the safety
and/or tolerability of the IL-1 Trap, which may limit its commercial potential
if the product candidate is ever approved for marketing and sale.


<P align="left" style="font-size: 10pt"><B>Regulatory and Litigation Risks</B>


<P align="left" style="font-size: 10pt"><B><I>If we do not obtain regulatory approval for our product candidates, we will not
be able to market or sell them.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We cannot sell or market products without regulatory approval. If we do
not obtain and maintain regulatory approval for our product candidates, the
value of our company and our results of operations will be harmed. In the
United States, we must obtain and maintain approval from the FDA for each drug
we intend to sell. Obtaining FDA approval is typically a lengthy and expensive
process, and approval is highly uncertain. Foreign governments also regulate
drugs distributed in their country and approval in any country is likely to be
a lengthy and expensive process, and approval is highly uncertain. None of our
product candidates has ever received regulatory approval to be marketed and
sold in the United States or any other country. We may never receive
regulatory approval for any of our product candidates.

<P align="left" style="font-size: 10pt"><B><I>If the testing or use of our products harms people, we could be subject to
costly and damaging product liability claims. We could also face costly and
damaging claims arising from employment law, securities law, environmental law,
or other applicable laws governing our operations.</I></B>



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<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The testing, manufacturing, marketing, and sale of drugs for use in people
expose us to product liability risk. We are currently involved in a product
liability lawsuit brought by a subject who participated in a clinical trial of
one of our drug candidates. Any informed consent or waivers obtained from
people who sign up for our clinical trials may not protect us from liability or
the cost of litigation. Our product liability insurance may not cover all
potential liabilities or may not completely cover any liability arising from
any such litigation. Moreover, we may not have access to liability insurance
or be able to maintain our insurance on acceptable terms.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In May&nbsp;2003, securities class action lawsuits were commenced against
Regeneron and certain of its officers and directors in the United States
District Court for the Southern District of New York. A consolidated amended
class action complaint was filed in October&nbsp;2003. The complaint, which
purports to be brought on behalf of a class consisting of investors in our
publicly traded securities between March&nbsp;28, 2000 and March&nbsp;30, 2003, alleges
that the defendants misstated or omitted material information concerning the
safety and efficacy of AXOKINE, in violation of Sections 10(b) and 20(a) of the
Securities and Exchange Act of 1934, and Rule&nbsp;10b-5 promulgated thereunder.
Damages are sought in an unspecified amount. No reserve for damages has been
established because we do not believe that a loss is probable. However, if the
outcome of the litigation is adverse to us, we could be subject to significant
liability, which could exceed our insurance coverage.

<P align="left" style="font-size: 10pt"><B><I>Our operations may involve hazardous materials and are subject to
environmental, health, and safety laws and regulations. We may incur
substantial liability arising from our activities involving the use of
hazardous materials.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;As a biopharmaceutical company with significant manufacturing operations,
we are subject to extensive environmental, health, and safety laws and
regulations, including those governing the use of hazardous materials. Our
research and development and manufacturing activities involve the controlled
use of chemicals, viruses, radioactive compounds, and other hazardous
materials. The cost of compliance with environmental, health, and safety
regulations is substantial. If an accident involving these materials or an
environmental discharge were to occur, we could be held liable for any
resulting damages, or face regulatory actions, which could exceed our resources
or insurance coverage.


<P align="left" style="font-size: 10pt"><B>Risks Related to our Dependence on Third Parties</B>


<P align="left" style="font-size: 10pt"><B><I>On February&nbsp;27, 2004, Novartis provided notice to us that they would not
participate in the continued development and commercialization of the IL-1 Trap
under our collaboration agreement. This may harm our ability to develop and
commercialize the IL-1 Trap.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We relied heavily on Novartis to provide their expertise, resources,
funding, manufacturing capacity, clinical expertise, and commercial
infrastructure to support the IL-1 Trap program. Novartis&#146; decision to
withdraw from participating in the development and commercialization of the
IL-1 Trap may delay or disrupt the IL-1 Trap program. We do not have the
resources and skills to replace those of Novartis, which could result in
significant delays in the development and potential commercialization of the
IL-1 Trap. In addition, we will have to fund the


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<P align="left" style="font-size: 10pt">development and commercialization of the IL-1 Trap without Novartis&#146;
long-term commitment, which will require substantially greater expenditures on
our part.


<P align="left" style="font-size: 10pt"><B><I>If our collaboration with Aventis for the VEGF Trap is terminated, our ability
to develop and commercialize the VEGF Trap in the time expected, or at all, and
our business operations would be harmed.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We rely heavily on Aventis to assist with the development of the VEGF
Trap. If the VEGF Trap program continues, we will rely on Aventis to assist
with providing commercial manufacturing capacity, enrolling and monitoring
clinical trials, obtaining regulatory approval, particularly outside the United
States, and providing sales and marketing support. While we cannot assure you
that the VEGF Trap will ever be successfully developed and commercialized, if
Aventis does not perform its obligations in a timely manner, or at all, our
ability to develop, manufacture, and commercialize the VEGF Trap will be
significantly adversely affected. Aventis has the right to terminate its
collaboration agreement with us at any time. If Aventis were to terminate its
collaboration agreement with us, we might not have the resources or skills to
replace those of our partner, which could cause significant delays in the
development and/or manufacture of the VEGF Trap and result in substantial
additional costs to us. We have no sales, marketing, or distribution
capabilities. Termination of the Aventis collaboration agreement would create
new and additional risks to the successful development of the VEGF Trap.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Sanofi-Synthelabo and Aventis have reached agreement on a merger. It is
unclear what the impact of this or any other business combination involving
Aventis would have on the VEGF Trap collaboration, including the possibility of
a termination of the collaboration agreement and a delay in, or disruption to,
the VEGF Trap development program.

<P align="left" style="font-size: 10pt"><B><I>Our collaborators and service providers may fail to perform adequately in
their efforts to support the development, manufacture, and commercialization of
our drug candidates</I></B><B>.</B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We depend upon third-party collaborators, including Aventis and service
providers such as clinical research organizations, outside testing
laboratories, clinical investigator sites, and third party manufacturers and
product packagers and labelers, to assist us in the development of our product
candidates. If any of our existing collaborators or service providers breaches
or terminates its agreement with us or does not perform its development or
manufacturing services under an agreement in a timely manner or at all, we
would experience additional costs, delays, and difficulties in the development
or ultimate commercialization of our product candidates.


<P align="left" style="font-size: 10pt"><B>Risks Related to the Manufacture of our Product Candidates</B>


<P align="left" style="font-size: 10pt"><B><I>We have limited manufacturing capacity, which could inhibit our ability to
successfully develop or commercialize our drugs.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Before approving a new drug or biologic product, the FDA requires that the
facilities at which the product will be manufactured be in compliance with
current good manufacturing practices, or cGMP requirements. Manufacturing
product candidates in compliance with these regulatory requirements is complex,
time-consuming, and expensive. To be successful, our


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<P align="left" style="font-size: 10pt">products must be manufactured for development and, following approval, in
commercial quantities, in compliance with regulatory requirements and at
competitive costs. If we or any of our product collaborators or third-party
manufacturers, fillers, or labelers are unable to maintain regulatory
compliance, the FDA can impose regulatory sanctions, including, among other
things, refusal to approve a pending application for a new drug or biologic
product, or revocation of a pre-existing approval. As a result, our business,
financial condition, and results of operations may be materially harmed.



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Our manufacturing facility is
likely to be inadequate to produce sufficient quantities of product for
commercial sale. We intend to rely on our corporate collaborators, as well as
contract manufacturers, to produce the large quantities of drug material needed
for commercialization of our products. We rely entirely on third party
manufacturers for filling and finishing services. We will have to depend on
these manufacturers to deliver material on a timely basis and to comply with
regulatory requirements. If we are unable to supply sufficient material on
acceptable terms, or if we should encounter delays or difficulties in our
relationships with our corporate collaborators or contract manufacturers, our
business, financial condition, and results of operations may be materially
harmed.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We may expand our own manufacturing capacity to support commercial
production of active pharmaceutical ingredients, or API, for our product candidates. This will require substantial
additional funds, and we will need to hire and train significant numbers of
employees and managerial personnel to staff our facility. Start-up costs can
be large and scale-up entails significant risks related to process development
and manufacturing yields. We may be unable to develop manufacturing facilities
that are sufficient to produce drug material for clinical trials or commercial
use. In addition, we may be unable to secure adequate filling and finishing
services to support our products. As a result, our business, financial
condition, and results of operations may be materially harmed.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We may be unable to obtain key raw materials and supplies for the
manufacture of our product candidates. In addition, we may face difficulties
in developing or acquiring production technology and managerial personnel to
manufacture sufficient quantities of our product candidates at reasonable costs
and in compliance with applicable quality assurance and environmental
regulations and governmental permitting requirements.

<P align="left" style="font-size: 10pt"><B><I>If any of our clinical programs are discontinued, we may face costs related to
the unused capacity at our manufacturing facilities.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We maintain an 8,000 square foot manufacturing facility in Tarrytown, New
York and have large-scale manufacturing operations in Rensselaer, New York.
Under a long-term manufacturing agreement with Merck, we produce an
intermediate for a Merck pediatric vaccine at our facility in Rensselaer, New
York. We also use our facilities to produce API for our own clinical and
preclinical candidates. If we no longer use our facilities to manufacture the
Merck intermediate or clinical candidates are discontinued, we would have to
absorb overhead costs and inefficiencies.


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<P align="left" style="font-size: 10pt"><B><I>Certain of our raw materials are single-sourced from third parties; third-party
supply failures could adversely affect our ability to supply our products.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Certain raw materials necessary for manufacturing and formulation of our
product candidates are provided by single-source unaffiliated third-party
suppliers. We would be unable to obtain these raw materials for an
indeterminate period of time if these third-party single-source suppliers were
to cease or interrupt production or otherwise fail to supply these materials or
products to us for any reason, including due to regulatory requirements or
action, due to adverse financial developments at or affecting the supplier, or
due to labor shortages or disputes. This, in turn, could materially and
adversely affect our ability to manufacture our product candidates for use in
clinical trials, which could materially and adversely affect our operating
results.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Also, certain of the raw materials required in the manufacturing and the
formulation of our clinical candidates may be derived from biological sources,
including mammalian tissues, bovine serum and human serum albumin, or HSA.
There are certain European regulatory restrictions on using these biological
source materials. If we are required to substitute these sources to comply
with European regulatory requirements, our clinical development activities may
be delayed or interrupted.


<P align="left" style="font-size: 10pt"><B>Risks Related to Commercialization of Products</B>


<P align="left" style="font-size: 10pt"><B><I>If we are unable to establish sales, marketing, and distribution capabilities,
or enter into agreements with third parties to do so, we will be unable to
successfully market and sell future products.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We have no sales or distribution personnel or capabilities and have only a
small staff with marketing capabilities. If we are unable to obtain those
capabilities, either by developing our own organizations or entering into
agreements with service providers, we will not be able to successfully sell any
products that we may bring to market in the future. In that event, we will not
be able to generate significant revenue, even if our product candidates are
approved. We cannot guarantee that we will be able to hire the qualified sales
and marketing personnel we need or that we will be able to enter into
marketing, or distribution agreements with third-party providers on acceptable
terms, if at all. Currently, we rely on Aventis for sales, marketing, and
distribution of the VEGF Trap. We will have to rely on a third party or devote
significant resources to develop our own sales, marketing and distribution
capabilities for our other product candidates and we may be unsuccessful in
developing our own sales, marketing, and distribution organization.

<P align="left" style="font-size: 10pt"><B><I>We may be unable to formulate or manufacture our product candidates in a way
that is suitable for clinical or commercial use.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Changes in product formulations and manufacturing processes may be
required as product candidates progress in clinical development and are
ultimately commercialized. If we are unable to develop suitable product
formulations or manufacturing processes to support large scale clinical testing
of our product candidates, including VEGF Trap, IL-1 Trap, IL-4/13 Trap and
AXOKINE, we may be unable to supply necessary materials for our clinical
trials, which would


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<P align="left" style="font-size: 10pt">delay the development of our product candidates. Similarly, if we are
unable to supply sufficient quantities of product or develop product
formulations suitable for commercial use, we will not be able to successfully
commercialize our product candidates. For example, AXOKINE is currently
formulated for delivery in single use vials. We are in the process of
developing a formulation that may be used in multiple use vials. If we are
unable to develop this multiple use vial formulation, potential future AXOKINE
sales and profitability may be limited. In addition, we are in the process of
developing formulations that would allow delivery of higher doses of the IL-1
Trap to test in clinical trials. This includes formulations for subcutaneous
and intravenous administration. If we are unable to develop or manufacture
such a higher dose formulation that can be produced in a cost-effective manner,
potential future IL-1 Trap sales and profitability may be limited.


<P align="left" style="font-size: 10pt"><B><I>Even if our product candidates are ever approved, their commercial success is
highly uncertain because our competitors may get to the marketplace before we
do with better or lower cost drugs.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;There is substantial competition in the biotechnology and pharmaceutical
industries from pharmaceutical, biotechnology, and chemical companies. Many of
our competitors have substantially greater research, preclinical, and clinical
product development and manufacturing capabilities, and financial, marketing,
and human resources than we do. Our smaller competitors may also be
significant if they acquire or discover patentable inventions, form
collaborative arrangements, or merge with large pharmaceutical companies. Even
if we achieve product commercialization, our competitors have achieved, and may
continue to achieve product commercialization before our products are approved
for marketing and sale. Genentech has an approved VEGF antagonist on the
market and many different pharmaceutical and biotechnology companies are
working to develop competing VEGF antagonists, including Novartis and Pfizer.
Many of these molecules are farther along in development than the VEGF Trap and
may offer competitive advantages over our molecule. The marketing approval for
Genentech&#146;s VEGF antagonist, Avastin<SUP>TM</SUP>, may make it more difficult for us to
enroll patients in clinical trials to support the VEGF Trap. This may delay or
impair our ability to successfully develop and commercialize the VEGF Trap.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The markets for both rheumatoid arthritis and asthma are both very
competitive. Several highly successful medicines are available for these
diseases. Examples include the TNF-antagonists Enbrel<SUP>&#174;</SUP> (a registered trademark
of Amgen), Remicade<SUP>&#174;</SUP> (a registered trademark of Centocor), and Humira<SUP>&#174;</SUP> (a
registered trademark of Abbott) for rheumatoid arthritis, and the
leukotriene-modifier Singulair<SUP>&#174;</SUP> (a registered trademark of Merck), as well as
various inexpensive corticosteroid medicines for asthma. The availability of
highly effective FDA approved TNF-antagonists makes it more difficult to
successfully develop the IL-1 Trap for the treatment of rheumatoid arthritis,
since it will be difficult to enroll patients with rheumatoid arthritis to
participate in clinical trials of the IL-1 Trap. This may delay or impair our
ability to successfully develop the drug candidate. In addition, even if the
IL-1 Trap is ever approved for sale, it will be difficult for our drug to
compete against these FDA approved TNF-antagonists because doctors and patients
will have significant experience using these effective medicines. Moreover,
these approved therapeutics may offer competitive advantages over the IL-1
Trap, such as requiring fewer injections.


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<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;There is also substantial competition in the discovery and development of
treatments for obesity, as well as established, cost-effective, and emerging
surgical, prescription, and over-the-counter treatments for the disease that
may offer competitive advantages over AXOKINE. AXOKINE is available only in
injectible form, while the currently available marketed medicines for the
treatment of obesity, and a late-stage product candidate in development by
Sanofi-Synthelabo, are delivered in pill form, which is generally favored over
injectible medicines. Therefore, even if AXOKINE is approved for sale, the
fact that it must be delivered by injection may severely limit its market
acceptance among patients and physicians.

<P align="left" style="font-size: 10pt"><B><I>The successful commercialization of our product candidates will depend on
obtaining coverage and reimbursement for use of these products from third-party
payors.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Sales of biopharmaceutical products largely depend on the reimbursement of
patients&#146; medical expenses by government health care programs and private
health insurers. Without the financial support of the governments or
third-party payors, the market for any biopharmaceutical product will be
limited. These third-party payors increasingly challenge the price and
examining the cost-effectiveness of products and services. Significant
uncertainty exists as to the reimbursement status of any new therapeutic,
particularly if there exist lower-cost standards of care. Third-party payors
may not reimburse sales of our products, which would harm our business.


<P align="left" style="font-size: 10pt"><B>Risks Related to Employees</B>


<P align="left" style="font-size: 10pt"><B><I>We are dependent on our key personnel and if we cannot recruit and retain
leaders in our research, development, manufacturing, and commercial
organizations, our business will be harmed.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We are highly dependent on our executive officers. If we are not able to
retain any of these persons or our Chairman, our business may suffer. In
particular, we depend on the services of Roy Vagelos, M.D., the Chairman of our
Board of Directors, Leonard Schleifer, M.D., Ph.D., our President and Chief
Executive Officer, and George D. Yancopoulos, M.D., Ph.D., our Executive Vice
President, Chief Scientific Officer and President, Regeneron Research
Laboratories. There is intense competition in the biotechnology industry for
qualified scientists and managerial personnel in the development, manufacture,
and commercialization of drugs. We may not be able to continue to attract and
retain the qualified personnel necessary for developing our business.


<P align="left" style="font-size: 10pt"><B>Risks Related to Intellectual Property</B>


<P align="left" style="font-size: 10pt"><B><I>If we cannot protect the confidentiality of our trade secrets or our patents
are insufficient to protect our proprietary rights, our business and
competitive position will be harmed.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Our business requires using sensitive and proprietary technology and other
information that we protect as trade secrets. We seek to prevent improper
disclosure of these trade secrets through confidentiality agreements. If our
trade secrets are improperly exposed, either by our


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<P align="left" style="font-size: 10pt">own employees or our collaborators, it would help our competitors and
adversely affect our business. We will be able to protect our proprietary
rights from unauthorized use by third parties only to the extent that our
rights are covered by valid and enforceable patents or are effectively
maintained as trade secrets. The patent position of biotechnology companies
involves complex legal and factual questions and, therefore, enforceability
cannot be predicted with certainty. Our patents may be challenged,
invalidated, or circumvented. Patent applications filed outside the United
States may be challenged by third parties who file an opposition. Such
opposition proceedings are increasingly common in the European Union and are
costly to defend. We have patent applications that are being opposed and it is
likely that we will need to defend additional patent applications in the
future. Our patent rights may not provide us with a proprietary position or
competitive advantages against competitors. Furthermore, even if the outcome
is favorable to us, the enforcement of our intellectual property rights can be
expensive and time consuming.


<P align="left" style="font-size: 10pt"><B><I>We may be restricted in our development and/or commercialization activities by
third party patents.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Our commercial success depends significantly on our ability to operate
without infringing the patents and other proprietary rights of third parties.
Other parties may allege to have blocking patents to our Trap products in
clinical development, either because they claim to hold proprietary rights to
fusion proteins or proprietary rights to components of the Trap or the way it
is manufactured. We are aware of certain United States and foreign patents
relating to particular IL-4 and IL-13 receptors. Our IL-4/13 Trap includes
portions of the IL-4 and IL-13 receptors. In addition, we are aware of a broad
patent held by Genentech relating to proteins fused to certain immunoglobulin
domains. Our Trap product candidates include proteins fused to immunoglobulin
domains. Although we do not believe that we are infringing third party
patents, the holders of these patents may sue us for infringement and a court
may find that we are infringing one or more validly issued patents, which may
materially harm our business.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Any patent holders could sue us for damages and seek to prevent us from
manufacturing, selling, or developing our drug candidates, and a court may find
that we are infringing validly issued patents of third parties. In the event
that the manufacture, use, or sale of any of our clinical candidates infringes
on the patents or violates other proprietary rights of third parties, we may be
prevented from pursuing product development, manufacturing, and
commercialization of our drugs and may be required to pay costly damages. Such
a result may materially harm our business, financial condition, and results of
operations. Legal disputes are likely to be costly and time consuming to
defend.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We seek to obtain licenses to patents when, in our judgment, such licenses
are needed. If any licenses are required, we may not be able to obtain such
licenses on commercially reasonable terms, if at all. The failure to obtain
any such license could prevent us from developing or commercializing any one or
more of our product candidates, which could severely harm our business.


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<P align="left" style="font-size: 10pt"><B>Risks Related to our Common Stock</B>



<P align="left" style="font-size: 10pt"><B><I>Our stock price may be extremely volatile.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;There has been significant volatility in our stock price and generally in
the market prices of biotechnology companies&#146; securities. Various factors and
events may have a significant impact on the market price of our Common Stock.
These factors include, by way of example:


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&#149;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>progress, delays, or adverse results in clinical trials;</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&#149;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>announcement of technological innovations or product candidates by us or
competitors;</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&#149;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>fluctuations in our operating results;</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&#149;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>public concern as to the safety or effectiveness of our product candidates;</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&#149;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>developments in our relationship with collaborative partners;</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&#149;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>developments in the biotechnology industry or in government regulation of
healthcare;</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&#149;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>large sales of our common stock by our executive officers, directors, or
significant shareholders;</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&#149;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>arrivals and departures of key personnel; and</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&#149;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>general market conditions.</TD>
</TR>

</TABLE>

<P align="left" style="font-size: 10pt">The trading price of our Common Stock has been, and could continue to be,
subject to wide fluctuations in response to these and other factors, including
the sale or attempted sale of a large amount of our Common Stock in the market.
Broad market fluctuations may also adversely affect the market price of our
Common Stock.


<P align="left" style="font-size: 10pt"><B><I>Future sales of our Common Stock by our significant shareholders or us may
depress our stock price.</I></B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;A number of our shareholders own a substantial amount of our Common Stock.
If our significant shareholders or we sell substantial amounts of our Common
Stock in the public market, the market price of our Common Stock could fall.
Sales by our significant shareholders, including Amgen, Aventis, and Novartis,
also might make it more difficult for us to sell equity or equity-related
securities in the future at a time and price that we deemed appropriate.

<DIV align="left">
<A name="109"></A>
</DIV>

<P align="left" style="font-size: 10pt"><B>Item&nbsp;3. Quantitative and Qualitative Disclosure About Market Risk.</B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Our earnings and cash flows are subject to fluctuations due to changes in
interest rates primarily from our investment of available cash balances in
investment grade corporate and U.S. government securities. We do not believe
we are materially exposed to changes in interest rates. Under our current
policies we do not use interest rate derivative instruments to manage exposure
to interest rate changes. We estimated that a one percent change in interest
rates would result in an approximately $0.9&nbsp;million and $0.4&nbsp;million change in
the fair market value of our investment portfolio at March&nbsp;31, 2004 and 2003,
respectively. The increase is due primarily to a higher investment portfolio
balance and slightly longer duration to maturity as of March&nbsp;31, 2004 in
comparison to 2003.


<P align="center" style="font-size: 10pt">36
</DIV>

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<DIV style="font-family: 'Times New Roman',Times,serif">
<DIV align="left">
<A name="110"></A>
</DIV>

<P align="left" style="font-size: 10pt"><B>Item&nbsp;4. Controls and Procedures</B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;We conducted an evaluation of the effectiveness of our disclosure controls
and procedures as of the end of the period covered by this Quarterly Report on
Form 10-Q. The evaluation was conducted under the supervision and with the
participation of Leonard S. Schleifer, our President and Chief Executive
Officer, and Murray A. Goldberg, our Chief Financial Officer. Based upon this
evaluation, each of Dr.&nbsp;Schleifer and Mr.&nbsp;Goldberg concluded that our
disclosure controls and procedures are effective in timely alerting them to
material information required to be included in our filings under the
Securities Exchange Act of 1934. There has been no significant change in our
internal controls over financial reporting during the period covered by this
report that has materially affected, or is reasonably likely to materially
affect, our internal control over financial reporting.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Our management, including our Chief Executive Officer and Chief Financial
Officer, does not expect that our disclosure controls and procedures or
internal controls over financial reporting will prevent all errors and all
fraud. A control system, no matter how well conceived and operated, can
provide only reasonable, not absolute, assurance that the objectives of the
system are met and cannot detect all deviations. Because of the inherent
limitations in all control systems, no evaluation of controls can provide
absolute assurance that all control issues and instances of fraud or
deviations, if any, within the company have been detected. While we believe
that our disclosure controls and procedures have been effective, in light of
the foregoing, we intend to continue to examine and refine our disclosure
controls and procedures and monitor ongoing developments in this area.


<P align="center" style="font-size: 10pt">37
</DIV>

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<DIV style="font-family: 'Times New Roman',Times,serif">
<DIV align="left">
<A name="111"></A>
</DIV>

<P align="left" style="font-size: 10pt"><B>PART II. OTHER INFORMATION</B>


<DIV align="left">
<A name="112"></A>
</DIV>

<P align="left" style="font-size: 10pt"><B>Item&nbsp;1. Legal Proceedings</B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In May&nbsp;2003, securities class action lawsuits were commenced against
Regeneron and certain of its officers and directors in the United States
District Court for the Southern District of New York. A consolidated amended
class action complaint was filed in October&nbsp;2003. The complaint, which purport
to be brought on behalf of a class consisting of investors in our publicly
traded securities between March&nbsp;28, 2000 and March&nbsp;30, 2003, alleges that the
defendants misstated or omitted material information concerning the safety and
efficacy of AXOKINE, in violation of Sections 10(b) and 20(a) of the Securities
and Exchange Act of 1934, and Rule&nbsp;10b-5 promulgated thereunder. Damages are
sought in an unspecified amount. We believe that the lawsuit is without merit
and in December&nbsp;2003, we filed a motion to dismiss the lawsuit. Because we do
not believe that a loss is probable, no legal reserve has been established.


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;From time to time we are a party to other legal proceedings in the course
of our business. We do not expect any other legal proceedings to have a
material adverse effect on our business or financial condition.

<DIV align="left">
<A name="113"></A>
</DIV>

<P align="left" style="font-size: 10pt"><B>Item&nbsp;6. Exhibits and Reports on Form&nbsp;8-K</B>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;Exhibits

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="75%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="8%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="71%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD nowrap align="left"><B>Exhibit</B></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="5"><B>&nbsp;</B></TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD nowrap align="left"><B>Number</B><HR size="1" noshade></TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" colspan="5"><B>Description</B><HR size="1" noshade></TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">3.1
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">(a)
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">-
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Restated Certificate of Incorporation of Regeneron
Pharmaceuticals, Inc., as of June&nbsp;21, 1991.</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">3.2
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">(b)
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">-
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">By-Laws of the Company, currently in effect (amended as of
January&nbsp;22, 1995).</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">10.1
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">(c)
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">-
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Certificate of Amendment of the Restated Certificate of
Incorporation of Regeneron Pharmaceuticals, Inc., as of October&nbsp;18,
1996.</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">10.2
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">(d)
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">-
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Certificate of Amendment of the Certificate of Incorporation
of Regeneron Pharmaceuticals, Inc., as of December&nbsp;17, 2001.</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">31
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">-
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Certification of CEO and CFO pursuant to Rule&nbsp;13a-14(a) under the
Securities and Exchange Act of 1934.</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">32
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">-
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Certification of CEO and CFO pursuant to 18 U.S.C. Section&nbsp;1350.</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<B>Description:</B>


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="2%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">(a)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Incorporated by reference from the Form 10-Q for Regeneron
Pharmaceuticals, Inc. for the quarter ended June&nbsp;30, 1991, filed August
13, 1991.</TD>
</TR>

</TABLE>

<P align="center" style="font-size: 10pt">38
</DIV>

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<DIV style="font-family: 'Times New Roman',Times,serif">


<P><TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">


<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="7%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">(b)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Incorporated by reference from the Form 10-K for Regeneron
Pharmaceuticals, Inc. for the fiscal year ended December&nbsp;31, 1994,
filed March&nbsp;30, 1995.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="2%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">(c)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Incorporated by reference from the Form 10-Q for Regeneron
Pharmaceuticals, Inc. for the quarter ended September&nbsp;30, 1996, filed
November&nbsp;5, 1996.</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="2%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">(d)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Incorporated by reference from the Form 10-K for Regeneron
Pharmaceuticals, Inc. for the fiscal year ended December&nbsp;31, 2001,
filed March&nbsp;22, 2002.</TD>
</TR>

</TABLE>


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;Reports


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="2%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><DIV style="margin-left:10px; text-indent:-0px">Form&nbsp;8-K, filed April&nbsp;27, 2004: On April&nbsp;26, 2004, we issued a press
release announcing our first quarter 2004 financial and operating
results.</DIV></TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="2%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD><DIV style="margin-left:10px; text-indent:-0px">Form&nbsp;8-K, filed April&nbsp;28, 2004: On April&nbsp;28, 2004, we announced that we
gave our consent to Amgen Inc. to enter into a forward contract for the
sale of approximately 2.9&nbsp;million shares of our Common Stock,
representing Amgen&#146;s entire holding of our Common Stock.</DIV></TD>
</TR>

</TABLE>

<P align="center" style="font-size: 10pt">39
</DIV>

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<DIV style="font-family: 'Times New Roman',Times,serif">


<P><TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">



</TABLE>

<DIV align="left">
<A name="114"></A>
</DIV>

<P align="center" style="font-size: 10pt"><B>SIGNATURE</B>


<P align="left" style="font-size: 10pt">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 thereunto duly authorized.


<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="40%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="55%">&nbsp;</TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom">
    <TD valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="3" valign="top" align="left">Regeneron Pharmaceuticals, Inc.</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">

<TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">Date:
May&nbsp;6, 2004
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">By:
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">/s/ Murray A. Goldberg</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><HR size="1" noshade width="40%" align="left"></TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="3" valign="top" align="left">Murray A. Goldberg</TD>
</TR>

<TR valign="bottom">
    <TD valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="3" valign="top" align="left">Senior Vice President, Finance &#038; Administration,</TD>
</TR>

<TR valign="bottom">
    <TD valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="3" valign="top" align="left">Chief Financial Officer,Treasurer, and</TD>
</TR>

<TR valign="bottom">
    <TD valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="3" valign="top" align="left">Assistant Secretary</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>




<P align="center" style="font-size: 10pt">40
</DIV>


</BODY>
</HTML>

</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-31
<SEQUENCE>2
<FILENAME>y96986exv31.htm
<DESCRIPTION>EXHIBIT 31-302 CERTIFICATION OF CEO AND CFO
<TEXT>
<HTML>
<HEAD>
<TITLE>EXHIBIT 31-302 CERTIFICATION OF CEO AND CFO</TITLE>
</HEAD>
<BODY bgcolor="#FFFFFF">
<!-- PAGEBREAK -->
<H5 align="left" style="page-break-before:always">&nbsp;</H5><P>
<DIV style="font-family: 'Times New Roman',Times,serif">


<P align="right" style="font-size: 10pt">Exhibit&nbsp;31



<DIV align="center" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<B>Certification
of CEO and CFO Pursuant to</B></DIV>


<DIV align="center" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<B>Rule&nbsp;13a-</B><B>14(a)</B><B>
under the Securities Exchange Act</B></DIV>


<DIV align="center" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<B>of
1934, as Adopted Pursuant to</B></DIV>


<DIV align="center" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<B>Section&nbsp;302
of the Sarbanes-Oxley Act of 2002</B></DIV>


<P align="left" style="font-size: 10pt">I, Leonard S. Schleifer, certify that:



<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">1.</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>I have reviewed this quarterly report on Form 10-Q of Regeneron
Pharmaceuticals, Inc.;</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">2.</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Based on my knowledge, this quarterly report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to
make the statements made, in light of the circumstances under which such
statements were made, not misleading with respect to the period covered by
this report;</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">3.</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Based on my knowledge, the financial statements, and other financial
information included in this quarterly report, fairly present in all
material respects the financial condition, results of operations, and cash
flows of the registrant as of, and for, the periods presented in this
report;</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">4.</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>The registrant&#146;s other certifying officer and I are responsible for
establishing and maintaining disclosure controls and procedures (as
defined in Exchange Act Rules&nbsp;13a-15(e) and 15d-15(e)) for the registrant
and have:</TD>
</TR>

</TABLE>


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="4%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">a)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Designed such disclosure controls and procedures, or
caused such disclosure controls and procedures to be designed
under our supervision, to ensure that material information
relating to the registrant is made known to us by others within
the registrant, particularly during the period in which this
quarterly report is being prepared;</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="4%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">b)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Evaluated the effectiveness of the registrant&#146;s
disclosure controls and procedures and presented in this
quarterly report our conclusions about the effectiveness of the
disclosure controls and procedures, as of the end of the period
covered by this report based on such evaluation; and</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="4%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">c)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Disclosed in this report any change in the
registrant&#146;s internal control over financial reporting that
occurred during the registrant&#146;s most recent fiscal quarter that
has materially affected, or is reasonably likely to materially
affect, the registrant&#146;s internal control over financial
reporting; and</TD>
</TR>

</TABLE>


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">5.</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>The registrant&#146;s other certifying officer and I have disclosed, based on
our most recent evaluation of internal control over financial reporting,
to the registrant&#146;s</TD>
</TR>

</TABLE>

<P align="center" style="font-size: 10pt">&nbsp;
</DIV>

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<DIV style="font-family: 'Times New Roman',Times,serif">


<P><TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">



</TABLE>


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>auditors and the audit committee of registrant&#146;s board of directors (or
persons performing the equivalent functions):</TD>
</TR>

</TABLE>


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="4%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">a)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>All significant deficiencies and material weaknesses
in the design or operation of internal control over financial
reporting which are reasonably likely to adversely affect the
registrant&#146;s ability to record, process, summarize and report
financial information; and</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="4%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">b)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Any fraud, whether or not material, that involves
management or other employees who have a significant role in the
registrant&#146;s internal control over financial reporting.</TD>
</TR>

</TABLE>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="40%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="55%">&nbsp;</TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom">

<TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">Date: May&nbsp;6, 2004
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">By:
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">/s/ Leonard S. Schleifer</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><HR size="1" noshade width="40%" align="left"></TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="3" valign="top" align="left">Leonard S. Schleifer, M.D., Ph.D.</TD>
</TR>

<TR valign="bottom">
    <TD valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="3" valign="top" align="left">President and Chief Executive Officer</TD>
</TR>

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</TABLE>
</DIV>



<P align="center" style="font-size: 10pt">&nbsp;
</DIV>

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<H5 align="left" style="page-break-before:always">&nbsp;</H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">


<P align="left" style="font-size: 10pt">I, Murray A. Goldberg, certify that:



<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">1.</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>I have reviewed this quarterly report on Form 10-Q of Regeneron
Pharmaceuticals, Inc.;</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">2.</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Based on my knowledge, this quarterly report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to
make the statements made, in light of the circumstances under which such
statements were made, not misleading with respect to the period covered by
this report;</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">3.</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Based on my knowledge, the financial statements, and other financial
information included in this quarterly report, fairly present in all
material respects the financial condition, results of operations, and cash
flows of the registrant as of, and for, the periods presented in this
report;</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">4.</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>The registrant&#146;s other certifying officer and I are responsible for
establishing and maintaining disclosure controls and procedures (as
defined in Exchange Act Rules&nbsp;13a-15(e) and 15d-15(e)) for the registrant
and have:</TD>
</TR>

</TABLE>


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="4%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">a)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Designed such disclosure controls and procedures, or
caused such disclosure controls and procedures to be designed
under our supervision, to ensure that material information
relating to the registrant is made known to us by others within
the registrant, particularly during the period in which this
quarterly report is being prepared;</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="4%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">b)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Evaluated the effectiveness of the registrant&#146;s
disclosure controls and procedures and presented in this
quarterly report our conclusions about the effectiveness of the
disclosure controls and procedures, as of the end of the period
covered by this report based on such evaluation; and</TD>
</TR>

<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="4%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">c)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Disclosed in this report any change in the
registrant&#146;s internal control over financial reporting that
occurred during the registrant&#146;s most recent fiscal quarter that
has materially affected, or is reasonably likely to materially
affect, the registrant&#146;s internal control over financial
reporting; and</TD>
</TR>

</TABLE>


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="1%" nowrap align="right">5.</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>The registrant&#146;s other certifying officer and I have disclosed, based on
our most recent evaluation of internal control over financial reporting,
to the registrant&#146;s auditors and the audit committee of registrant&#146;s board
of directors (or persons performing the equivalent functions):</TD>
</TR>

</TABLE>


<P>
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="4%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">a)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>All significant deficiencies and material weaknesses
in the design or operation of internal control over financial
reporting which are reasonably likely to adversely affect the
registrant&#146;s ability to record, process, summarize and report
financial information; and</TD>
</TR>

</TABLE>

<P align="center" style="font-size: 10pt">&nbsp;
</DIV>

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<H5 align="left" style="page-break-before:always">&nbsp;</H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">


<P><TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">


<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="4%" style="background: transparent">&nbsp;</TD>
    <TD width="1%" nowrap align="right">b)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Any fraud, whether or not material, that involves
management or other employees who have a significant role in the
registrant&#146;s internal control over financial reporting.</TD>
</TR>

</TABLE>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="40%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD>
    <TD width="55%">&nbsp;</TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom">

<TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">Date:
May&nbsp;6, 2004
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">By:
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">/s/ Murray A. Goldberg</TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top"><HR size="1" noshade width="40%" align="left"></TD>
</TR>

<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="3" valign="top" align="left">Murray A. Goldberg</TD>
</TR>

<TR valign="bottom">
    <TD valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="3" valign="top" align="left">Senior Vice President, Finance &#038;</TD>
</TR>

<TR valign="bottom">
    <TD valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="3" valign="top" align="left">Administration, Chief Financial Officer,</TD>
</TR>

<TR valign="bottom">
    <TD valign="top">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="3" valign="top" align="left">Treasurer, and Assistant Secretary</TD>
</TR>

<!-- End Table Body -->
</TABLE>
</DIV>




<P align="center" style="font-size: 10pt">&nbsp;
</DIV>


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</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-32
<SEQUENCE>3
<FILENAME>y96986exv32.htm
<DESCRIPTION>EXHIBIT 32-906 CERTIFICATION OF CEO AND CFO
<TEXT>
<HTML>
<HEAD>
<TITLE>EXHIBIT 32-906 CERTIFICATION OF CEO AND CFO</TITLE>
</HEAD>
<BODY bgcolor="#FFFFFF">
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<H5 align="left" style="page-break-before:always">&nbsp;</H5><P>
<DIV style="font-family: 'Times New Roman',Times,serif">


<P align="right" style="font-size: 10pt">Exhibit&nbsp;32



<P align="center" style="font-size: 10pt"><B>Certification of CEO and CFO Pursuant to<BR>
18 U.S.C. Section&nbsp;1350,<BR>
As Adopted Pursuant to<BR>
Section&nbsp;906 of the Sarbanes-Oxley Act of 2002</B>


<P align="left" style="font-size: 10pt">In connection with the Quarterly Report of Regeneron Pharmaceuticals, Inc. (the
&#147;Company&#148;) on Form 10-Q for the quarterly period ending March&nbsp;31, 2004 as filed
with the Securities and Exchange Commission on the date hereof (the &#147;Report&#148;),
Leonard S. Schleifer, M.D., Ph.D., as Chief Executive Officer of the Company,
and Murray A. Goldberg, as Chief Financial Officer of the Company, each hereby
certifies, pursuant to 18 U.S.C. &#167; 1350, as adopted pursuant to &#167; 906 of the
Sarbanes-Oxley Act of 2002, to the best of his knowledge, that:



<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(1)&nbsp;The Report fully complies with the requirements of section 13(a) or
15(d) of the Securities Exchange Act of 1934; and


<P align="left" style="font-size: 10pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(2)&nbsp;The information contained in the Report fairly presents, in all
material respects, the financial condition and results of operations of the
Company.


<P align="left" style="font-size: 10pt">/s/ Leonard S. Schleifer
<DIV style="margin-left:10px; text-indent:-10px; font-size: 10pt">
<HR size="1" noshade width="45%" align="left"></DIV>
<DIV style="margin-left:10px; text-indent:-10px; font-size: 10pt">
Leonard S. Schleifer, M.D., Ph.D.</DIV>
<DIV style="margin-left:10px; text-indent:-10px; font-size: 10pt">
Chief Executive Officer</DIV>
<DIV style="margin-left:10px; text-indent:-10px; font-size: 10pt">
May&nbsp;6, 2004
</DIV>

<P align="left" style="font-size: 10pt">/s/ Murray A. Goldberg
<DIV style="margin-left:10px; text-indent:-10px; font-size: 10pt">
<HR size="1" noshade width="45%" align="left"></DIV>
<DIV style="margin-left:10px; text-indent:-10px; font-size: 10pt">
Murray A. Goldberg</DIV>
<DIV style="margin-left:10px; text-indent:-10px; font-size: 10pt">
Chief Financial Officer</DIV>
<DIV style="margin-left:10px; text-indent:-10px; font-size: 10pt">
May&nbsp;6, 2004
</DIV>
<P align="left" style="font-size: 10pt">This certification accompanies the Report pursuant to &#167; 906 of the
Sarbanes-Oxley Act of 2002 and shall not, except to the extent required by the
Sarbanes-Oxley Act of 2002, be deemed filed by the Company for purposes of &#167; 18
of the Securities Exchange Act of 1934, as amended.




<P align="center" style="font-size: 10pt">
</DIV>

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</SUBMISSION>
