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&lt;p style="FONT-FAMILY: times"&gt;&lt;font size="2"&gt;&lt;b&gt;L. Acquisition of ViroChem Pharma&amp;nbsp;Inc. &lt;/b&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;On March&amp;nbsp;12, 2009, the Company acquired 100% of the outstanding equity of ViroChem Pharma&amp;nbsp;Inc. ("ViroChem"), a privately-held biotechnology company based in Canada, for $100.0&amp;nbsp;million in cash and 10,733,527 shares of the Company's common stock. Vertex acquired ViroChem in order to add two clinical-development stage HCV polymerase inhibitors to Vertex's HCV drug development portfolio. The Company accounted for the transaction under the acquisition method of accounting. The Company recognized all of the assets acquired and liabilities assumed in the transaction at their acquisition-date fair values and expensed as incurred all transaction costs and restructuring costs associated with the transaction. The intangible assets and goodwill related to the ViroChem acquisition are tested for impairment on an annual basis as of October&amp;nbsp;1, and more frequently if indicators are present or changes in circumstance suggest that impairment may exist. &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;All of the intangible assets acquired in the ViroChem acquisition related to in-process research and development assets. The in-process research and development assets primarily related to ViroChem's two clinical-development stage HCV polymerase inhibitors, VX-222 and VX-759. As of March&amp;nbsp;31, 2011 and December&amp;nbsp;31, 2010, VX-222 and VX-759 account for all of the intangible assets reflected on the Company's condensed consolidated balance sheets with values of $412.9&amp;nbsp;million and $105.8&amp;nbsp;million, respectively. The Company's condensed consolidated balance sheets also reflect goodwill that relates to the potential synergies from the possible development of combination therapies involving telaprevir and the acquired drug candidates. No impairment has been found for VX-222 or VX-759 or goodwill since the acquisition date. &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 deferred tax liability of $160.3&amp;nbsp;million as of March&amp;nbsp;31, 2011 and December&amp;nbsp;31, 2010 primarily relates to the tax impact of future amortization or impairments associated with the identified intangible assets acquired, which are not deductible for tax purposes. &lt;/font&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;
</NonNumbericText><NonNumericTextHeader>L. Acquisition of ViroChem Pharma&amp;nbsp;Inc.
&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;On March&amp;nbsp;12, 2009, the Company acquired 100% of the</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 a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. This element may be used as a single block of text to encapsulate the entire disclosure (including data and tables) regarding business combinations, including leverage buyout transactions (as applicable).</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 141
 -Paragraph 51, 52

Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Emerging Issues Task Force (EITF)
 -Number 88-16

Reference 3: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 141R
 -Paragraph 67-73

Reference 4: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 141R
 -Paragraph F4
 -Subparagraph e
 -Appendix F

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