Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Mar. 31, 2021	Dec. 31, 2020
CASH FLOWS FROM OPERATING ACTIVITIES
Net Loss	$ (8,823)	$ (8,005)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	235	258
Stock-based compensation	2,147	1,379
Patent write-off	6	0
Operating lease right-of-use asset amortization	155	147
Finance lease right-of-use asset amortization	10	0
Changes in assets and liabilities:
Accounts Receivable	(107)	73
Prepaid expenses and other current assets	(26)	(156)
Other assets	62	0
Accounts payable	281	51
Accrued expenses	(149)	(256)
Accrued salaries and payroll related expenses	(281)	(308)
Operating lease liabilities	(165)	(148)
Deferred revenue	(488)	(262)
Net cash used in operating activities	(7,143)	(7,227)
CASH FLOWS FROM INVESTING ACTIVITIES
Purchase of property and equipment	(294)	(200)
Expenditures for patents	(328)	(132)
Net cash used in investing activities	(622)	(332)
CASH FLOWS FROM FINANCING ACTIVITIES
Gross proceeds from the sale of common stock	4,220	28,750
Offering costs in connection with sale of common stock	(126)	(2,290)
Proceeds from exercise of stock options	291	0
Net cash provided by financing activities	4,385	26,460
Effects of exchange rates on cash, cash equivalents and restricted cash	1	0
NET INCREASE (DECREASE) IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH	(3,379)	18,901
CASH, CASH EQUIVALENTS AND RESTRICTED CASH — Beginning of period	25,073	10,838	$ 10,838
CASH, CASH EQUIVALENTS AND RESTRICTED CASH — End of period	21,694	29,739	25,073
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Taxes Paid	1	1
SUPPLEMENTAL DISCLOSURE OF NON-CASH ACTIVITIES
Common stock issued in settlement of accrued salaries and payroll related expenses	0	280
Property and equipment included in accounts payable	71	142
Property and equipment included in accrued expenses	0	46
Patents included in accounts payable	95	84
Finance lease included in accounts payable	4	0
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents
Cash and cash equivalents				$ 21,589	$ 24,968
Restricted cash				105	105
Total cash, cash equivalents and restricted cash	$ 25,073	$ 29,739	$ 25,073	$ 21,694	$ 25,073