Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash	$ 87,820	$ 172,604
Accounts receivable, net	2,960	1,381
Inventory, net	2,211	2,020
Prepaid expenses and other current assets	4,467	5,111
Total current assets	97,458	181,116
Property and equipment, net	18,389	22,267
Right-of-use lease asset	15,491
Restricted cash	909	909
Restricted cash		909
Total assets	132,247	204,292
Current liabilities:
Accounts payable	4,177	8,572
Accrued expenses	9,312	8,485
Accrued payroll and related expenses	8,332	7,509
Lease liability, current portion	2,766
Deferred rent, current portion	0	1,370
Total current liabilities	24,587	25,936
Lease liability, less current portion	26,481
Deferred rent, less current portion	0	13,609
Deferred royalty obligation, net		124,323
Other noncurrent liabilities	12,790	4,503
Total liabilities	188,237	168,371
Commitments and contingencies (Note 10)
Shareholders’ (deficit) equity:
Common Stock, $0.0001 par value; 100,000,000 shares authorized, 27,195,469 and 26,259,254 shares issued and outstanding at December 31, 2019 and December 31, 2018, respectively	3	3
Additional paid-in capital	977,432	950,258
Accumulated deficit	(1,037,331)	(920,983)
Total shareholders’ (deficit) equity	(55,990)	35,921
Total liabilities and shareholders’ (deficit) equity	132,247	204,292
Series C-1 Convertible Preferred Stock [Member]
Shareholders’ (deficit) equity:
Convertible preferred stock, value	3,906	3,906
Series F Convertible Preferred Stock [Member]
Shareholders’ (deficit) equity:
Convertible preferred stock, value	$ 0	$ 2,737