Condensed Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 8,352	$ 24,571
Prepaid expenses and other current assets	144	255
Total current assets	8,496	24,826
Property and equipment, net	268	458
Restricted cash	311	311
Total assets	9,075	25,595
Current liabilities:
Accounts payable	1,377	1,203
Accrued expenses	2,870	4,882
Total current liabilities	4,247	6,085
Warrant and other liabilities	1,172	1,565
Total liabilities	5,419	7,650
Commitments and contingencies
Series D Redeemable Convertible Preferred Stock, $0.01 par value, Authorized, issued and outstanding - 1,124 shares; Redemption amount $9,149; Liquidation preference $9,309	5,921	5,921
Non-redeemable preferred stock, common stock, and other stockholders' (deficit) equity:
Preferred stock, $0.01 par value, Authorized - 5,000 shares Series A convertible preferred stock, Designated - 1,500 shares, Issued and outstanding - 1 share
Common stock, $0.001 par value, Authorized - 140,000 and 70,000 shares at September 30, 2012 and December 31, 2011, respectively Issued and outstanding - 27,641 and 27,637 shares at September 30, 2012 and December 31, 2011, respectively	28	28
Additional paid-in capital	388,567	387,414
Accumulated deficit	(390,860)	(375,418)
Total stockholders' (deficit) equity	(2,265)	12,024
Total liabilities, redeemable preferred stock and stockholders' (deficit) equity	$ 9,075	$ 25,595