CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash	$ 1,215	$ 3,495
Restricted cash	388	388
Accounts receivable	1,083	1,692
Other receivable	4	2
Inventory	2,704	2,129
Operating lease - right-of-use asset	372	553
Prepaid expenses and other current assets	1,074	1,263
Total current assets	6,840	9,522
Property and equipment, net	707	710
Intangible assets, net	25,602	26,024
Other assets	127	154
Total assets	33,276	36,410
Current liabilities:
Accounts payable	5,597	5,352
Accrued liabilities	3,309	2,922
Warrant liability	2	3
Operating lease liability	228	337
Notes payable, net of discount	7,132	6,778
Total current liabilities	16,268	15,392
Notes payable long term	400	450
Total liabilities	16,668	15,842
Commitments and contingencies (See Note 6)
Stockholders' equity:
Additional paid-in capital	145,861	142,046
Accumulated deficit	(141,026)	(133,090)
Total stockholders' equity	6,233	10,673
Total liabilities, convertible preferred stock and stockholders' equity	33,276	36,410
Series A
Current liabilities:
Series A redeemable convertible preferred stock: $0.0001 par value, 5,524,926 shares authorized at March 31, 2020 and December 31, 2019; 5,524,926 shares issued and outstanding at March 31, 2020 and December 31, 2019; (redemption amount of $12,738,822 at March 31, 2020 and December 31, 2019; liquidation preference of $9,199,002 at March 31, 2020 and December 31, 2019)	10,375	9,895
Series B convertible preferred stock
Current liabilities:
Series A redeemable convertible preferred stock: $0.0001 par value, 5,524,926 shares authorized at March 31, 2020 and December 31, 2019; 5,524,926 shares issued and outstanding at March 31, 2020 and December 31, 2019; (redemption amount of $12,738,822 at March 31, 2020 and December 31, 2019; liquidation preference of $9,199,002 at March 31, 2020 and December 31, 2019)	476	476
Stockholders' equity:
Preferred stock value	476	476
Series B-1 convertible preferred stock
Stockholders' equity:
Preferred stock value
Series B-2 convertible preferred stock
Current liabilities:
Series A redeemable convertible preferred stock: $0.0001 par value, 5,524,926 shares authorized at March 31, 2020 and December 31, 2019; 5,524,926 shares issued and outstanding at March 31, 2020 and December 31, 2019; (redemption amount of $12,738,822 at March 31, 2020 and December 31, 2019; liquidation preference of $9,199,002 at March 31, 2020 and December 31, 2019)	916	1,236
Stockholders' equity:
Preferred stock value	916	1,236
Common stock - voting
Stockholders' equity:
Common stock value	2	1
Common stock - non-voting
Stockholders' equity:
Common stock value	$ 4	$ 4