Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Operating activities:
Net loss	$ (37,304)	$ (28,933)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	307	250
Stock-based compensation	5,021	1,932
Non-cash interest expense	273	91
Accretion of discounts on investments, net	51	(649)
Amortization of right-of-use asset	624	580
Change in fair value of warrant liability	75
Changes in operating assets and liabilities
Prepaid expenses and other current assets	(4,155)	(558)
Accounts payable and accrued liabilities	(503)	44
Lease liability	(600)	(505)
Net cash used in operating activities	(36,211)	(27,748)
Investing activities:
Purchases of property and equipment	(206)	(84)
Purchases of short-term investments	(79,874)	(53,029)
Sales and maturities of short-term investments	47,983	70,810
Net cash (used in) provided by investing activities	(32,097)	17,697
Financing activities:
Proceeds from issuance of common stock from initial public offering, net of issuance costs	76,874
Proceeds from exercise of common stock options	161	38
Repurchase of unvested common stock	(2)	(1)
Proceeds from issuance of long-term debt, net of issuance cost		9,717
Net cash provided by financing activities	77,033	9,754
Net increase (decrease) in cash and cash equivalents	8,725	(297)
Cash and cash equivalents at beginning of year	15,668	15,965
Cash and cash equivalents at end of year	24,393	15,668
Supplemental disclosure of cash flow information:
Cash paid for interest	737	193
Supplemental non-cash investing and financing activities:
Conversion of convertible preferred stock to common stock	122,465
Conversion of convertible preferred stock warrant to common stock warrant	259
Initial fair value of warrant liability		184
Vesting of common stock	$ 80	$ 99