Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 154,408	$ 90,915
Inventory	820	0
Prepaid expenses and other current assets	6,326	3,147
Total current assets	161,554	94,062
Property and equipment, net	24,438	24,568
Restricted cash	909	909
Total assets	186,901	119,539
Current liabilities:
Accounts payable	7,321	11,484
Accrued clinical and other expenses	4,280	703
Accrued payroll and related expenses	3,044	4,995
Deferred rent, current portion	1,370	1,370
Total current liabilities	16,015	18,552
Deferred rent, less current portion	13,473	12,785
Total liabilities	29,488	31,337
Shareholders’ equity:
Common Stock, $0.0001 par value; 100,000,000 shares authorized, 26,154,439 and 22,167,529 shares issued and outstanding at March 31, 2018 and December 31, 2017, respectively	3	2
Additional paid-in capital	922,809	803,071
Accumulated deficit	(772,042)	(721,514)
Total shareholders’ equity	157,413	88,202
Total liabilities and shareholders’ equity	186,901	119,539
Series C-1 Convertible Preferred Stock [Member]
Shareholders’ equity:
Convertible preferred stock, value	3,906	3,906
Series F Convertible Preferred Stock [Member]
Shareholders’ equity:
Convertible preferred stock, value	$ 2,737	$ 2,737