Condensed Consolidated Balance Sheets - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 18,836,000	$ 11,703,000
Accounts receivable	848,000	924,000
Prepaid expenses and other current assets	522,000	758,000
Inventories	45,000	25,000
Total current assets	20,251,000	13,410,000
Property and equipment, net	593,000	353,000
Right-of-use asset	421,000	52,000
Other assets		13,000
Total assets	21,265,000	13,828,000
Current liabilities:
Accounts payable	1,315,000	1,158,000
Accrued liabilities	2,815,000	2,588,000
Short-term debt	476,000	193,000
Lease liability	9,000	39,000
Total current liabilities	4,615,000	3,978,000
Non-current liabilities:
Long-term debt	1,678,000	1,099,000
Lease liability	422,000	13,000
Total liabilities	6,715,000	5,090,000
Commitments and contingencies (Note 3)
Stockholders' equity:
Common stock, par value $0.001 per share, 150,000,000 shares authorized at September 30, 2020 and December 31, 2019; 104,041,493 and 97,286,157 shares issued and outstanding at September 30, 2020 and December 31, 2019, respectively	104,000	97,000
Additional paid-in capital	448,431,000	430,802,000
Accumulated deficit	(433,985,000)	(422,161,000)
Total stockholders' equity	14,550,000	8,738,000
Total liabilities and stockholders' equity	$ 21,265,000	$ 13,828,000