Subsequent Event

3 Months Ended

Mar. 31, 2012

Subsequent Event

Subsequent Event

10. Subsequent Event

Sale of Stock

On April 2, 2012, the Company and GSK entered into a common stock purchase agreement, under which the Company will issue, and GSK will acquire, through an affiliate, 10,000,000 shares of the Company’s common stock at a price of $21.2887 per share, for a total investment of $212,887,000. This transaction is subject to certain closing conditions, including approval of the Company’s stockholders at the annual meeting of stockholders scheduled for May 15, 2012, and expiration of the waiting period under the Hart-Scott-Rodino Act. The agreement may be terminated (i) by GSK if, on any day before the closing of the private placement, the closing S&P 500 index is more than thirty percent (30%) less than the closing S&P 500 index on March 30, 2012, or the Company’s Board of Directors changes its recommendation to stockholders to vote in favor of the private placement or (ii) by either of the parties if a vote of the Company’s stockholders does not approve the private placement or if the private placement has not closed by July 15, 2012.