Condensed Consolidated Statements Of Operations (USD $) In Thousands, except Per Share data	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Condensed Consolidated Statements Of Operations
Collaboration revenue	$ 15,799	$ 15,792	$ 30,508	$ 31,526
Operating expenses:
Research and development	19,139	18,255	36,757	43,837
Selling, general and administrative	7,036	4,974	13,192	12,813
Total operating expenses	26,175	23,229	49,949	56,650
Loss from operations	(10,376)	(7,437)	(19,441)	(25,124)
Other income (expense):
Interest income	9	80	50	193
Other income (expense)	(99)	117	(432)	226
Total other income (expense)	(90)	197	(382)	419
Net loss before income tax	(10,466)	(7,240)	(19,823)	(24,705)
Income tax expense (benefit)	(992)		(1,897)
Net loss	$ (9,474)	$ (7,240)	$ (17,926)	$ (24,705)
Basic and diluted net loss per common share	$ (0.27)	$ (0.21)	$ (0.52)	$ (0.73)
Weighted average common shares used in the calculation of basic and diluted net loss per share	34,888	34,053	34,776	34,006

Basic net loss per share is computed by dividing the net loss by the weighted-average number of common shares outstanding during the period. Diluted net loss per share is computed similarly to basic net loss per share, except that the denominator is increased to include all dilutive potential common shares, including outstanding options and warrants. Potentially dilutive common shares have been excluded from the diluted loss per common share computations in all periods presented because such securities have an anti-dilutive effect on loss per common share due to the Company's net loss.

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