CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Share data	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Revenues from collaborative agreements	$ 150	$ 225	$ 300	$ 450
License fees and royalties	312	776	1,667	1,469
Total revenues	462	1,001	1,967	1,919
Operating expenses:
Research and development (including amounts for related parties: three months - 2011-none; 2010- $317; six months 2011-none; 2010-$644)	16,544	13,389	33,299	26,934
General and administrative	5,334	4,488	14,440	8,338
Total operating expenses	21,878	17,877	47,739	35,272
Loss from operations	(21,416)	(16,876)	(45,772)	(33,353)
Unrealized gain on derivatives, net	240	172	279	230
Interest and other income	287	194	583	396
Losses recognized under equity method investment	(168)	(496)	(503)	(892)
Interest and other expense	(31)	(25)	(64)	(52)
Net loss	$ (21,088)	$ (17,031)	$ (45,477)	$ (33,671)
Basic and diluted net loss per share (in dollars per share)	$ (0.17)	$ (0.18)	$ (0.37)	$ (0.35)
Shares used in computing basic and diluted net loss per share (in shares)	124,579,190	96,712,059	123,838,959	95,862,080

Revenue earned during the period relating to consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity. Royalty revenue is derived from a percentage or stated amount of sales proceeds or revenue generated by the third party using the entity's property. Examples of property from which royalties may be derived include patents and oil and mineral rights.

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