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   &lt;div align="left" style="font-size: 10pt; margin-top: 12pt"&gt;&lt;b&gt;17.&lt;/b&gt;&amp;#160;&amp;#160;&lt;b&gt;Related Parties&lt;/b&gt;
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   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt;  text-indent: 4%"&gt;Robert A. Ingram was Vice Chairman Pharmaceuticals of GSK from January&amp;#160;2008 through December
   2009, and serves as a strategic advisor to the Chief Executive Officer of GSK since January&amp;#160;2010.
   Mr.&amp;#160;Ingram has been a member of our board of directors since 2003. In 2008, Mr.&amp;#160;Ingram became our
   board&amp;#8217;s lead director. Stephen F. Stefano was Senior Vice President of GSK&amp;#8217;s Payor Markets Division
   from January&amp;#160;2001 through November&amp;#160;2009. Mr.&amp;#160;Stefano has been a member of our board of directors
   since March&amp;#160;2009. See Note 4 for discussion of the Collaboration Agreement with GSK.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt;  text-indent: 4%"&gt;Anders L&amp;#246;nner has been the Group President and Chief Executive Officer of Meda since 1999, and
   serves on Meda&amp;#8217;s board of directors. Effective January&amp;#160;7, 2009, Mr.&amp;#160;L&amp;#246;nner was elected by our board
   of directors to fill an open board position in the class expiring in 2011. See Notes 6 and 16 for
   discussion of transactions with Meda.
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   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt;  text-indent: 4%"&gt;G. Mason Morfit is a partner and a member of the Management Committee of ValueAct Capital. Mr.
   Morfit has been a member of our board of directors since 2007. Brandon B. Boze has been a Vice
   President at ValueAct Capital since 2005, and has been a member of our board of directors since
   December&amp;#160;2009. ValueAct Capital is the general partner and the manager of ValueAct Capital Master
   Fund, L.P. During the three months ended June&amp;#160;30, 2010, we purchased 2,637,545 shares of our common
   stock for a total of $106.6&amp;#160;million from ValueAct Capital Master Fund, L.P.
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