Condensed Consolidated Statement of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Cash flows from operating activities:
Net loss	$ (19,945)	$ (19,027)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	20	29
Gain on disposal of equipment	0	(26)
Stock-based compensation	722	5,983
Contingent payment settled in common stock	0	1,540
Changes in operating assets and liabilities:
Other current assets and prepaid expenses	(1,452)	(1,862)
Accounts payable	(676)	(1,423)
Other current liabilities	(1,007)	(55)
Accrued expenses	2,082	(1,463)
Net cash used in operating activities	(20,256)	(16,304)
Cash flows from investing activities:
Proceeds from sale of ELAD Assets	0	1,150
Cash acquired in connection with the Transaction	0	8,151
Purchases of property and equipment	(59)	(17)
Proceeds from sale of equipment	0	40
Net cash (used in) provided by investing activities	(59)	9,324
Cash flows from financing activities:
Proceeds from public offering of common stock through At The Market offering, net of issuance costs of $112	2,814	0
Net cash provided by financing activities	39,780	29,965
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(227)	64
Net change in cash, cash equivalents and restricted cash	19,238	23,049
Cash, cash equivalents and restricted cash, beginning of period	29,369	13,072
Cash, cash equivalents and restricted cash, end of period	48,607	36,121
Supplemental disclosures for cash flow information:
Cash paid for interest	0	34
Supplemental disclosure of noncash investing and financing activities:
Note receivable from sale of ELAD assets	0	920
Conversion of convertible preferred stock to common stock	0	37,193
Fair value of net assets acquired in the Transaction	0	39,400
Offering costs in accrued expenses	75	0
Pre-Closing Financing
Cash flows from financing activities:
Proceeds from issuance of common stock	0	29,965
April 2020 Equity Issuances
Cash flows from financing activities:
Proceeds from issuance of common stock	13,918	0
June 2020 Equity Issuances
Cash flows from financing activities:
Proceeds from issuance of common stock	$ 23,048	$ 0