Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Operating Activities
Net loss	$ (42,366)	$ (21,301)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	2,009	1,639
Depreciation and amortization	90	51
Changes in operating assets and liabilities:
Accounts receivable	1,342	13,012
Prepaid and other assets	(2,338)	2,267
Accounts payable	(4,091)	(2,780)
Accrued compensation and other accrued liabilities	663	1,825
Operating lease liability and right-of-use asset	157	31
Deferred revenue	55	(14,670)
Net cash flows used in operating activities	(44,479)	(19,926)
Investing Activities
Proceeds from maturities of short-term investments	38,632	50,493
Purchase of short-term investments		(47,081)
Purchases of property and equipment	(347)	(33)
Net cash flows provided by investing activities	38,285	3,379
Financing Activities
Issuance of common stock for public offering, net of issuance costs	49,250	60,112
Issuance of common stock from stock grants and option exercises	205	339
Net cash flow provided by financing activities	49,455	60,451
Net increase in cash and cash equivalents	43,261	43,904
Cash and cash equivalents at beginning of the period	30,360	15,369
Cash and cash equivalents at end of the period	73,621	$ 59,273
Supplemental Disclosure of Non-Cash Investing and Financing Activities:
Right-of-use assets obtained in exchange for operating lease liabilities	$ 1,850