Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 59,074	$ 120,841
Receivables from collaboration	23	50,436
Inventory-current		9,670
Deferred product costs from collaboration	13,539
Prepaid expenses and other current assets	4,018	20,206
Total current assets	76,654	201,153
Property and equipment - net	48,749	192,127
State research and development credit exchange receivable - net of current portion		311
Other assets	1,009	848
Total	126,412	394,439
Current liabilities:
Accounts payable	15,599	7,394
Accrued expenses and other current liabilities	7,929	26,206
Facility financing obligation	74,582	72,995
Senior convertible notes - current		99,355
Deferred product sales from collaboration	17,503	436
Purchase commitment liabilities - current	12,475
Deferred payments from collaboration	140,231	196,967
Total current liabilities	268,319	403,353
Note payable to principal stockholder	49,521	49,521
Sanofi loan facility and loss share obligation	62,371	3,034
Senior convertible notes - long term	27,613
Purchase commitments - long term	53,692
Other liabilities	15,225	12,301
Total liabilities	$ 476,741	$ 468,209
Commitments and contingencies
Stockholders' deficit:
Undesignated preferred stock, $0.01 par value - 10,000,000 shares authorized; no shares issued or outstanding at December 31, 2015 and 2014
Common stock, $0.01 par value - 550,000,000 shares authorized at December 31, 2015 and 2014, respectively; 428,670,943 and 406,059,089 shares issued and outstanding at December 31, 2015 and 2014, respectively	$ 4,287	$ 4,061
Additional paid-in capital	2,508,633	2,416,967
Accumulated other comprehensive loss	(20)	(14)
Accumulated deficit	(2,863,229)	(2,494,784)
Total stockholders' deficit	(350,329)	(73,770)
Total	$ 126,412	$ 394,439