Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Current Assets:
Cash and cash equivalents	$ 26,892	$ 10,189
Inventory	195	0
Prepaid expenses and other current assets	719	442
Total current assets	27,806	10,631
Property and equipment, net	1,737	2,293
Restricted cash	400	400
Total Assets	29,943	13,324
Current Liabilities:
Accounts payable	1,166	1,111
Accrued expenses	4,159	2,972
Common stock warrant liability	6,305	6,996
Equipment loans and capitalized leases, current portion	69	68
Total current liabilities	11,699	11,147
Equipment loans and capitalized leases, non-current portion	148	224
Other liabilities	443	689
Total liabilities	12,290	12,060
Stockholders' Equity:
Preferred stock, $0.001 par value; 5,000,000 shares authorized; no shares issued or outstanding	0	0
Common stock, $0.001 par value; 100,000,000 authorized; 43,673,636 and 24,602,706 issued, 43,652,744 and 24,581,814 shares outstanding	44	25
Additional paid-in capital	455,398	401,713
Accumulated deficit	(434,735)	(397,420)
Treasury stock (at cost); 20,892 shares	(3,054)	(3,054)
Total stockholders' equity	17,653	1,264
Total liabilities & stockholders' equity	$ 29,943	$ 13,324