Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 26,146	$ 21,239
Accounts receivable, net	1,706	1,503
Assets held for sale		53
Inventory	788	1,595
Prepaid expenses and other current assets	1,178	2,103
Total current assets	29,818	26,493
Property and equipment, net	78	98
Intangible assets, net	4,160	4,259
Operating lease right-of-use assets	2,598	4,836
Restricted cash	699	699
Total assets	37,353	36,385
Current liabilities:
Accounts payable	1,977	2,429
Accrued expenses	5,235	5,794
Operating lease liabilities	932	1,547
Total current liabilities	8,144	9,770
Long-term operating lease liabilities	1,754	3,448
Commitments and contingencies (Note 11)
Stockholders’ equity:
Preferred stock, par value $0.001 per share; 5,000 shares authorized; no shares issued and outstanding
Common stock, par value $0.001 per share; 125,000 shares authorized; 7,259 and 3,466 shares issued and outstanding at March 31, 2020 and December 31, 2019, respectively	7	3
Additional paid-in capital	643,699	627,291
Accumulated deficit	(616,251)	(604,127)
Total stockholders’ equity	27,455	23,167
Total liabilities and stockholders’ equity	$ 37,353	$ 36,385