Condensed Balance Sheets (USD $)	Sep. 30, 2011	Dec. 31, 2010
CURRENT ASSETS
Cash and cash equivalents	$ 69,600,199	$ 38,155,251
Prepaid expenses and other assets	943,710	2,469,879
TOTAL CURRENT ASSETS	70,543,909	40,625,130
PROPERTY AND EQUIPMENT, NET	854,989	635,776
OTHER ASSETS
Investments	3,405,807	3,405,807
Deposits	86,203	99,937
TOTAL ASSETS	74,890,908	44,766,650
CURRENT LIABILITIES
Accounts payable	6,041,891	4,864,217
Accrued compensation	1,476,036	526,022
Other accrued expenses	2,747,791	1,681,956
Current portion of convertible senior notes	1,234,000	1,111,132
TOTAL CURRENT LIABILITIES	11,499,718	8,183,327
Long-term convertible senior notes	19,242,333	17,436,201
TOTAL LIABILITIES	30,742,051	25,619,528
Capital stock
Capital stock	254,739,100	184,777,766
Accumulated deficit	(210,590,243)	(165,630,644)
TOTAL STOCKHOLDERS' EQUITY	44,148,857	19,147,122
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	74,890,908	44,766,650
Class C special stock
Capital stock
Capital stock	391	391
Common stock
Capital stock
Capital stock	$ 254,738,709	$ 184,777,375

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Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).