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USD ($)

USD ($) / shares

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&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&lt;b&gt;K. Collaborative Arrangements&lt;/b&gt;&lt;/font&gt;&lt;/p&gt;
&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&lt;i&gt;Janssen Pharmaceutica,&amp;nbsp;N.V.&lt;/i&gt;&lt;/font&gt;&lt;/p&gt;
&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;In June 2006, the Company entered into a collaboration agreement with Janssen Pharmaceutica,&amp;nbsp;N.V. ("Janssen") for the development, manufacture and commercialization of telaprevir. Under the agreement, Janssen has agreed to be responsible for 50% of the drug development costs incurred under the development program for the parties' territories (North America for the Company, and the rest of the world, other than the Far East, for Janssen) and has exclusive rights to commercialize telaprevir in its territories, including Europe, South America, the Middle East, Africa and Australia. &lt;/font&gt;&lt;/p&gt;
&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;Janssen made a $165.0&amp;nbsp;million up-front license payment to the Company in July 2006. The up-front license payment is being amortized over the Company's estimated period of performance under the collaboration agreement. The Company's estimates regarding the period of performance under the Janssen collaboration agreement were adjusted in 2007, in the third quarter of 2009 and in the first quarter of 2010, as a result of changes in the global development plan for telaprevir, which contemplates the conduct of certain development activities in the post-approval period, if telaprevir is approved for marketing. These adjustments were made on a prospective basis beginning in the periods in which the changes were identified and resulted in a decrease in the amount of revenues the Company recognized from the Janssen agreement by $2.6&amp;nbsp;million per quarter for the first adjustment, by $1.1&amp;nbsp;million per quarter for the second adjustment and by $1.4&amp;nbsp;million per quarter for the third adjustment. As of March&amp;nbsp;31, 2011, there was $65.2&amp;nbsp;million in deferred revenues related to this up-front license payment that the Company expects to recognize over the remaining estimated period of performance. &lt;/font&gt;&lt;/p&gt;
&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;Under the agreement, Janssen agreed to make contingent milestone payments for successful development, approval and launch of telaprevir as a product. At the inception of the agreement, the Company determined that all of these contingent milestones were substantive and would result in revenues in the period in which the milestone was achieved. As of March&amp;nbsp;31, 2011, the Company had earned $150.0&amp;nbsp;million of these contingent milestone payments, including a $50.0&amp;nbsp;million milestone payment that was earned in the first quarter of 2011 in connection with the European Medicines Agency's ("EMA") acceptance of the marketing authorization application ("MAA") for telaprevir. The remaining $200.0&amp;nbsp;million in contingent milestones that the Company could achieve under the Janssen agreement consist of $50.0&amp;nbsp;million related to the approval of telaprevir by the EMA, and $150.0&amp;nbsp;million related to the launch of telaprevir in the European Union. On September&amp;nbsp;30, 2009, the Company entered into two financial transactions related to $250.0&amp;nbsp;million in contingent Janssen milestones, including the $50.0&amp;nbsp;million milestone payment that was earned in the first quarter of 2011. Please refer to Note&amp;nbsp;M, "September 2009 Financial Transactions," for further information.&lt;/font&gt;&lt;/p&gt;
&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;Under the collaboration agreement for telaprevir, each party incurs internal and external reimbursable expenses related to the telaprevir development program and is reimbursed for 50% of these expenses. The Company recognizes the full amount of the reimbursable costs it incurs as research and development expenses on its condensed consolidated statements of operations. The Company recognizes amounts that Janssen is obligated to pay the Company with respect to reimbursable expenses net of reimbursable expenses incurred by Janssen as collaborative revenues. During the three months ended March&amp;nbsp;31, 2011, Janssen incurred more reimbursable costs than the Company for the first time under the collaboration agreement, and the net amount payable by the Company to reimburse Janssen for expenses for the first quarter of 2011 was recorded as a reduction of collaborative revenues. &lt;/font&gt;&lt;/p&gt;
&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;Each of the parties will be responsible for drug supply in their respective territories. The Company has agreed to provide Janssen certain services through the Company's third-party manufacturing network until June 2011. Reimbursements from Janssen for manufacturing services are recorded as collaborative revenues. &lt;/font&gt;&lt;/p&gt;
&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;The collaboration agreement with Janssen also provides the Company with royalties on any sales of telaprevir in the Janssen territories, with a tiered royalty averaging in the mid-20% range, as a percentage of net sales in the Janssen territories. In addition, Janssen will be responsible for certain third-party royalties on net sales in its territories. Janssen may terminate the agreement (A)&amp;nbsp;prior to the receipt of marketing approval for telaprevir, without cause at any time upon six months' notice to the Company, or (B)&amp;nbsp;if marketing approval has been obtained, upon the later of (i)&amp;nbsp;one year's advance notice and (ii)&amp;nbsp;such period as may be required to assign and transfer to the Company specified filings and approvals. The agreement also may be terminated by either party for a material breach by the other, subject to notice and cure provisions. Unless earlier terminated, the agreement will continue in effect until the expiration of Janssen's royalty obligations, which expire on a country-by-country basis with the last-to-expire patent covering telaprevir. In the European Union, the Company has a patent covering the composition-of-matter of telaprevir that expires in 2021 and expects to obtain extensions to the term of this patent through 2026. &lt;/font&gt;&lt;/p&gt;
&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;During the three months ended March&amp;nbsp;31, 2011 and 2010, the Company recognized the following collaborative revenues attributable to the Janssen collaboration: &lt;/font&gt;&lt;/p&gt;
&lt;div style="PADDING-RIGHT: 0pt; PADDING-LEFT: 0pt; PADDING-BOTTOM: 0pt; MARGIN-LEFT: 20%; WIDTH: 60%; PADDING-TOP: 0pt; POSITION: relative"&gt;
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&lt;tr style="HEIGHT: 0px"&gt;&lt;!-- TABLE COLUMN WIDTHS SET --&gt;
&lt;td style="FONT-FAMILY: times" align="left" width="10"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="left"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" width="12"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right" width="7"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" width="45"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" width="24"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right" width="7"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" width="39"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" width="12"&gt;&lt;/td&gt;&lt;!-- TABLE COLUMN WIDTHS END --&gt;&lt;/tr&gt;
&lt;tr style="HEIGHT: 0px" valign="bottom"&gt;
&lt;th style="FONT-FAMILY: times" align="left" colspan="2"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;br /&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/th&gt;
&lt;th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="5"&gt;&lt;font size="1"&gt;&lt;b&gt;Three&amp;nbsp;Months&amp;nbsp;Ended&lt;br /&gt;
March&amp;nbsp;31,&lt;/b&gt;&lt;/font&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/th&gt;&lt;/tr&gt;
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&lt;th style="FONT-FAMILY: times" align="left" colspan="2"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;br /&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/th&gt;
&lt;th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2"&gt;&lt;font size="1"&gt;&lt;b&gt;2011 &lt;/b&gt;&lt;/font&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/th&gt;
&lt;th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2"&gt;&lt;font size="1"&gt;&lt;b&gt;2010 &lt;/b&gt;&lt;/font&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/th&gt;&lt;/tr&gt;
&lt;tr style="HEIGHT: 0px" valign="bottom"&gt;
&lt;th style="FONT-FAMILY: times" align="left" colspan="2"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;br /&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times" align="center" colspan="5"&gt;&lt;font size="1"&gt;&lt;b&gt;(in thousands)&lt;/b&gt;&lt;/font&gt;&lt;br /&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/th&gt;&lt;/tr&gt;
&lt;tr style="HEIGHT: 0px" valign="bottom" bgcolor="#CCEEFF"&gt;
&lt;td style="FONT-FAMILY: times" colspan="2"&gt;
&lt;p style="MARGIN-LEFT: 10pt; TEXT-INDENT: -10pt; FONT-FAMILY: times"&gt;&lt;font size="2"&gt;Amortized portion of up-front payment&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;$&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;3,107&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;$&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;3,107&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="HEIGHT: 0px" valign="bottom" bgcolor="white"&gt;
&lt;td style="FONT-FAMILY: times" colspan="2"&gt;
&lt;p style="MARGIN-LEFT: 10pt; TEXT-INDENT: -10pt; FONT-FAMILY: times"&gt;&lt;font size="2"&gt;Milestone revenues&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;50,000&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;&amp;#151;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="HEIGHT: 0px" valign="bottom" bgcolor="#CCEEFF"&gt;
&lt;td style="FONT-FAMILY: times" colspan="2"&gt;
&lt;p style="MARGIN-LEFT: 10pt; TEXT-INDENT: -10pt; FONT-FAMILY: times"&gt;&lt;font size="2"&gt;Net reimbursement (payment) for telaprevir development costs&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;(1,145&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;)&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;2,406&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="HEIGHT: 0px" valign="bottom" bgcolor="white"&gt;
&lt;td style="FONT-FAMILY: times" colspan="2"&gt;
&lt;p style="MARGIN-LEFT: 10pt; TEXT-INDENT: -10pt; FONT-FAMILY: times"&gt;&lt;font size="2"&gt;Reimbursement for manufacturing services&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;4,154&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;951&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="FONT-SIZE: 1.5pt; HEIGHT: 0px" valign="top"&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom" colspan="2"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="HEIGHT: 0px" valign="bottom" bgcolor="#CCEEFF"&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="0"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;
&lt;p style="MARGIN-LEFT: 10pt; TEXT-INDENT: -10pt; FONT-FAMILY: times"&gt;&lt;font size="2"&gt;Total collaborative revenues attributable to the Janssen collaboration&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;$&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;56,116&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;$&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;6,464&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="FONT-SIZE: 1.5pt; HEIGHT: 0px" valign="top"&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom" colspan="2"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;/div&gt;
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&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&lt;i&gt;Mitsubishi Tanabe Pharma Corporation &lt;/i&gt;&lt;/font&gt;&lt;/p&gt;
&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;In June 2004, the Company entered into a collaboration agreement (the "MTPC Agreement") with Mitsubishi Tanabe Pharma Corporation ("Mitsubishi Tanabe"), pursuant to which Mitsubishi Tanabe agreed to provide financial and other support for the development and commercialization of telaprevir. Under the terms of the agreement, Mitsubishi Tanabe has the right to develop and commercialize telaprevir in Japan and certain other Far East countries. The MTPC Agreement provided for payments by Mitsubishi Tanabe to the Company through Phase&amp;nbsp;2 clinical development, including an up-front license fee, development-stage milestone payments and reimbursement of certain drug development costs for telaprevir. &lt;/font&gt;&lt;/p&gt;
&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;In July 2009, the Company and Mitsubishi Tanabe amended the MTPC Agreement. Under the amended agreement, Mitsubishi Tanabe paid the Company $105.0&amp;nbsp;million in the third quarter of 2009, and the Company may receive a further contingent milestone payment ranging from between $15.0&amp;nbsp;million to $65.0&amp;nbsp;million. The amended agreement provides to Mitsubishi Tanabe a fully-paid license to manufacture and commercialize telaprevir to treat HCV infection in Japan and specified other countries in the Far East. Mitsubishi Tanabe is responsible for its own development and manufacturing costs in its territory. Mitsubishi Tanabe may terminate the agreement at any time without cause upon 60&amp;nbsp;days' prior written notice to the Company. The agreement also may be terminated by either party for a material breach by the other, subject to notice and cure provisions. Unless earlier terminated, the agreement will continue in effect until the expiration of the last-to-expire patent covering telaprevir. In Japan, the Company has a patent covering the composition-of-matter of telaprevir that expires in 2021. &lt;/font&gt;&lt;/p&gt;
&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;Prior to the amendment, the Company recognized revenues based on an amortized portion of the 2004 up-front payment, milestones, if any, and reimbursement of certain of the Company's expenses incurred in telaprevir development. The $105.0&amp;nbsp;million payment that the Company received in the third quarter of 2009 pursuant to the amended agreement is a nonrefundable, up-front license fee and revenues related to this payment are being recognized on a straight-line basis over the expected period of performance of the Company's obligations under the amended agreement. As of March&amp;nbsp;31, 2011, there was $41.4&amp;nbsp;million in deferred revenues related to this up-front license payment that will be recognized over the remaining period of performance of the Company's obligations under the amended agreement. In connection with the amendment to the MTPC Agreement, the Company agreed to supply manufacturing services to Mitsubishi Tanabe through the Company's third-party manufacturing network. &lt;/font&gt;&lt;/p&gt;
&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;During the three months ended March&amp;nbsp;31, 2011 and 2010, the Company recognized the following collaborative revenues attributable to the Mitsubishi Tanabe collaboration:&lt;/font&gt;&lt;/p&gt;
&lt;div style="PADDING-RIGHT: 0pt; PADDING-LEFT: 0pt; PADDING-BOTTOM: 0pt; MARGIN-LEFT: 20%; WIDTH: 60%; PADDING-TOP: 0pt; POSITION: relative"&gt;
&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&lt;!-- COMMAND=ADD_TABLEWIDTH,"100%" --&gt;&lt;/font&gt;&lt;/p&gt;
&lt;!-- User-specified TAGGED TABLE --&gt;
&lt;div align="center"&gt;
&lt;table cellspacing="0" cellpadding="0" width="100%" border="0"&gt;
&lt;tr style="HEIGHT: 0px"&gt;&lt;!-- TABLE COLUMN WIDTHS SET --&gt;
&lt;td style="FONT-FAMILY: times" align="left" width="10"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="left"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" width="12"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right" width="7"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" width="45"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" width="24"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right" width="7"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" width="39"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" width="12"&gt;&lt;/td&gt;&lt;!-- TABLE COLUMN WIDTHS END --&gt;&lt;/tr&gt;
&lt;tr style="HEIGHT: 0px" valign="bottom"&gt;
&lt;th style="FONT-FAMILY: times" align="left" colspan="2"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;br /&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/th&gt;
&lt;th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="5"&gt;&lt;font size="1"&gt;&lt;b&gt;Three&amp;nbsp;Months&amp;nbsp;Ended&lt;br /&gt;
March&amp;nbsp;31,&lt;/b&gt;&lt;/font&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/th&gt;&lt;/tr&gt;
&lt;tr style="HEIGHT: 0px" valign="bottom"&gt;
&lt;th style="FONT-FAMILY: times" align="left" colspan="2"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;br /&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/th&gt;
&lt;th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2"&gt;&lt;font size="1"&gt;&lt;b&gt;2011 &lt;/b&gt;&lt;/font&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/th&gt;
&lt;th style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" align="center" colspan="2"&gt;&lt;font size="1"&gt;&lt;b&gt;2010 &lt;/b&gt;&lt;/font&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/th&gt;&lt;/tr&gt;
&lt;tr style="HEIGHT: 0px" valign="bottom"&gt;
&lt;th style="FONT-FAMILY: times" align="left" colspan="2"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;br /&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times" align="center" colspan="5"&gt;&lt;font size="1"&gt;&lt;b&gt;(in thousands)&lt;/b&gt;&lt;/font&gt;&lt;br /&gt;&lt;/th&gt;
&lt;th style="FONT-FAMILY: times"&gt;&lt;font size="1"&gt;&amp;nbsp;&lt;/font&gt;&lt;/th&gt;&lt;/tr&gt;
&lt;tr style="HEIGHT: 0px" valign="bottom" bgcolor="#CCEEFF"&gt;
&lt;td style="FONT-FAMILY: times" colspan="2"&gt;
&lt;p style="MARGIN-LEFT: 10pt; TEXT-INDENT: -10pt; FONT-FAMILY: times"&gt;&lt;font size="2"&gt;Amortized portion of up-front payments&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;$&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;9,558&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;$&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;9,558&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="HEIGHT: 0px" valign="bottom" bgcolor="white"&gt;
&lt;td style="FONT-FAMILY: times" colspan="2"&gt;
&lt;p style="MARGIN-LEFT: 10pt; TEXT-INDENT: -10pt; FONT-FAMILY: times"&gt;&lt;font size="2"&gt;Development milestone revenues&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;1,212&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;&amp;#151;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="HEIGHT: 0px" valign="bottom" bgcolor="#CCEEFF"&gt;
&lt;td style="FONT-FAMILY: times" colspan="2"&gt;
&lt;p style="MARGIN-LEFT: 10pt; TEXT-INDENT: -10pt; FONT-FAMILY: times"&gt;&lt;font size="2"&gt;Payments for manufacturing services&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;715&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;&amp;#151;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="FONT-SIZE: 1.5pt; HEIGHT: 0px" valign="top"&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom" colspan="2"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="HEIGHT: 0px" valign="bottom" bgcolor="white"&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="0"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;
&lt;p style="MARGIN-LEFT: 10pt; TEXT-INDENT: -10pt; FONT-FAMILY: times"&gt;&lt;font size="2"&gt;Total collaborative revenues attributable to the Mitsubishi Tanabe collaboration&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;$&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;11,485&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;$&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" align="right"&gt;&lt;font size="2"&gt;9,558&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&amp;nbsp;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="FONT-SIZE: 1.5pt; HEIGHT: 0px" valign="top"&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom" colspan="2"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times" valign="bottom" align="right" colspan="2"&gt;&amp;nbsp;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times" valign="bottom"&gt;&amp;nbsp;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;/div&gt;
&lt;!-- end of user-specified TAGGED TABLE --&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
</NonNumbericText><NonNumericTextHeader>K. Collaborative Arrangements
Janssen Pharmaceutica,&amp;nbsp;N.V.
&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;In June 2006, the Company entered into a</NonNumericTextHeader><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios></Cell></Cells><OriginalInstanceReportColumns /><Unit>Other</Unit><ElementDataType>us-types:textBlockItemType</ElementDataType><SimpleDataType>string</SimpleDataType><ElementDefenition>Description of collaborative arrangements in which the entity is a participant, including a) information about the nature and purpose of such arrangements; b) its rights and obligations under thereunder; c) the accounting policy for collaborative arrangements; and d) the income statement classification and amounts attributable to transactions arising from the collaborative arrangement between participants.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Emerging Issues Task Force (EITF)
 -Number 07-1
 -Paragraph 21

</ElementReferences><IsTotalLabel>false</IsTotalLabel><IsEPS>false</IsEPS><Label>Collaborative Arrangements</Label></Row></Rows><Footnotes /><NumberOfCols>1</NumberOfCols><NumberOfRows>2</NumberOfRows><ReportName>Collaborative Arrangements</ReportName><MonetaryRoundingLevel>UnKnown</MonetaryRoundingLevel><SharesRoundingLevel>UnKnown</SharesRoundingLevel><PerShareRoundingLevel>UnKnown</PerShareRoundingLevel><ExchangeRateRoundingLevel>UnKnown</ExchangeRateRoundingLevel><HasCustomUnits>false</HasCustomUnits><SharesShouldBeRounded>true</SharesShouldBeRounded></InstanceReport>
