Condensed Balance Sheets (USD $)	Jun. 30, 2011	Dec. 31, 2010
CURRENT ASSETS
Cash and cash equivalents	$ 37,126,006	$ 38,155,251
Prepaid expenses and other assets	1,013,315	2,469,879
TOTAL CURRENT ASSETS	38,139,321	40,625,130
PROPERTY AND EQUIPMENT, NET	1,132,519	635,776
OTHER ASSETS
Investments	3,405,807	3,405,807
Deposits	86,203	99,937
TOTAL ASSETS	42,763,850	44,766,650
CURRENT LIABILITIES
Accounts payable	6,348,948	4,864,217
Accrued compensation	1,072,972	526,022
Other accrued expenses	2,872,081	1,681,956
Current portion of convertible senior notes	1,187,497	1,111,132
TOTAL CURRENT LIABILITIES	11,481,498	8,183,327
Long-term convertible senior notes	19,751,836	17,436,201
TOTAL LIABILITIES	31,233,334	25,619,528
Capital stock
Capital stock	209,387,067	184,777,766
Accumulated deficit	(197,856,551)	(165,630,644)
TOTAL STOCKHOLDERS' EQUITY	11,530,516	19,147,122
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	42,763,850	44,766,650
Class C special stock
Capital stock
Capital stock	391	391
Common stock
Capital stock
Capital stock	$ 209,386,676	$ 184,777,375