CONDENSED CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Current Assets
Cash and cash equivalents	$ 60,653	$ 75,807
Prepaid expenses and other current assets	383	189
Total current assets	61,036	75,996
Fixed assets, net	52	75
Other assets, net	3,192	2,906
Total assets	64,280	78,977
Current Liabilities
Accounts payable	3,737	2,966
Accrued expenses	348	586
Total current liabilities	4,085	3,552
Commitments and contingencies (note 6)
Stockholders' Equity
Undesignated Preferred Stock, $.001 par value, 5,000,000 shares authorized, none issued and outstanding	0	0
Common Stock, $.001 par value, 75,000,000 shares authorized, 23,221,809 and 23,125,565 shares issued, respectively and 23,109,459 and 23,013,215 shares outstanding, respectively	23	23
Additional paid-in capital	316,427	314,405
Cost of treasury stock, 112,350 shares	(1,380)	(1,380)
Deficit accumulated during the development stage	(254,875)	(237,623)
Total stockholders' equity	60,195	75,425
Total liabilities and stockholders' equity	$ 64,280	$ 78,977