EXHIBIT 12.1

	Ratio of Earnings to Fixed Charges (dollars in thousands, except ratio data)
	Year ended December 31,
	2011			2010			2009		2008			2007
Earnings (Loss):
Earnings (loss) before provision for income taxes	$	(381,106	)	$	(233,231	)	$	4,385	$	(268,891	)	$	(284,371	)
Fixed Charges		79,788			78,108			77,780		82,930			80,927
Total Earnings (Loss)	$	(301,318	)	$	(155,123	)	$	82,165	$	(185,961	)	$	(203,444	)
Fixed Charges:
Interest expense on indebtedness (including amortization of debt expense and discount)	$	62,056		$	59,500		$	58,424	$	62,912		$	60,716
Interest expense on portion of rent expense representative of interest		17,732			18,608			19,356		20,018			20,211
Total Fixed Charges	$	79,788		$	78,108		$	77,780	$	82,930		$	80,927
Ratio of Earnings to Fixed Charges		—			—			1.06		—			—
Coverage deficiency (1) (2) (3)	$	(381,106	)	$	(233,231	)	$	—	$	(268,891	)	$	(284,371	)

(1) The Company’s Coverage deficiency for 2011 includes a $50,000 upfront license fee payment to FivePrime Therapeutics, Inc., which is reflected in research and development expenses in the consolidated statement of operations.

(2) The Company’s Ratio of Earnings to Fixed Charges for 2009 includes a gain on extinguishment of debt of $38,873, a gain on sale of an equity investment of $5,259 and reflects revenues received in connection with the delivery of raxibacumab to the Strategic National Stockpile. These amounts should not be considered indicative of the Company’s future performance.

(3) The Company’s Coverage deficiency for 2008 includes a gain on the sale of an equity investment of $32,518 partially offset by a charge for impaired investment of $6,284.