Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash flows from operating activities
Net loss	$ (91,585)	$ (71,395)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	277	256
Stock-based compensation	11,660	8,055
Issuance of PIK interest debt	1,713
Accrued interest on revenue interest financing liability	2,657
Amortization of debt discount	1,049	698
Other	874	540
Changes in operating assets and liabilities:
Prepaid expenses and other current assets (includes the change in related party amounts of $0, and $82, respectively)	1,402	2,203
Accounts payable and accrued expenses (includes the change in related party amounts of $(1,102), and $722, respectively)	2,865	(12,860)
Accrued clinical trial expenses	(1,061)	(5,759)
Accrued interest	88	(10)
Operating right-of-use asset and lease liabilities	(293)	50
Other long-term assets	(464)	93
Net cash used in operating activities	(70,818)	(78,129)
Cash flows from investing activities
Cash paid for property, plant and equipment	(495)	(214)
Net cash used in investing activities	(495)	(214)
Cash flows from financing activities
Proceeds from issuance of common stock from exercise of stock options		516
Net proceeds from revenue interest financing transaction	95,446
Net cash provided by financing activities	95,446	516
Net increase (decrease) in cash and cash equivalents	24,133	(77,827)
Cash and cash equivalents – beginning of period	183,259	287,496
Cash and cash equivalents – end of period	207,392	209,669
Supplemental disclosure of cash flow information
Interest paid	2,919	1,833
Supplemental disclosure of noncash investing and financing activities
Property and equipment purchases included in accounts payable and accrued liabilities	16	3
Operating lease liabilities arising from obtaining right-of-use assets	554
Settlement of ESPP liability in common stock	515	358
Settlement of 401(k) liability in common stock	$ 254	$ 323