Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 71,157	$ 43,946
Restricted cash	527	4,409
Accounts receivable, net	4,017	2,789
Inventory	3,597	2,657
Deferred costs from commercial product sales		405
Prepaid expenses and other current assets	2,556	3,010
Total current assets	81,854	57,216
Property and equipment, net	25,602	26,922
Other assets	249	437
Total assets	107,705	84,575
Current liabilities:
Accounts payable	5,379	6,984
Accrued expenses and other current liabilities	15,022	12,449
Facility financing obligation	11,298	52,745
Deferred revenue, net		3,038
Deferred payments from collaborations - current	36,885	250
Recognized loss on purchase commitments - current	6,657	12,131
Total current liabilities	75,241	87,597
Note payable to related party	72,089	79,666
Accrued interest - note payable to related party	6,835	2,347
Senior convertible notes	19,099	24,411
Recognized loss on purchase commitments - long term	91,642	97,585
Deferred payments from collaborations - long term	10,680	500
Milestone rights liability	7,201	7,201
Total liabilities	282,787	299,307
Commitments and contingencies (Note 14)
Stockholders' deficit:
Undesignated preferred stock, $0.01 par value - 10,000,000 shares authorized; no shares issued or outstanding at December 31, 2018 and 2017
Common stock, $0.01 par value - 280,000,000 shares authorized, 187,029,967 and 119,053,414 shares issued and outstanding at December 31, 2018 and 2017, respectively	1,870	1,192
Additional paid-in capital	2,763,067	2,638,992
Accumulated other comprehensive loss	(19)	(18)
Accumulated deficit	(2,940,000)	(2,854,898)
Total stockholders' deficit	(175,082)	(214,732)
Total liabilities and stockholders' deficit	$ 107,705	$ 84,575