CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Cash flows from operating activities
Net loss	$ (66,664)	$ (58,794)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	284	178
Amortization of debt issuance costs	1,102	703
Accretion of revenue interest financing debt	2,916
Amortization of discount on short-term investments	(669)
Stock-based compensation expense	7,632	7,196
Amortization of net contract asset/liability	(837)	(566)
Noncash lease expense	102	165
Noncash lease liability	196	133
Write off of fixed assets	62	61
Issuance of common stock for cost of license agreement		1,169
Unrealized loss on foreign currency transactions		930
Changes in operating assets and liabilities:
Refund liability		(22,163)
Net contract asset/liability	1,569	10,566
Prepaid expenses and other current assets, non-current assets, inventory and accounts receivable	(7,441)	(2,481)
Accounts payable and accrued expenses	(4,088)	1,576
Net cash used in operating activities	(65,836)	(61,327)
Cash flows from investing activities
Proceeds from sale of property and equipment	4
Maturities of short-term investments	5,000
Purchases of short-term investments	(51,995)
Purchases of property and equipment		(421)
Net cash used in investing activities	(46,991)	(421)
Cash flows from financing activities
Proceeds from exercise of stock options	484	1,747
Proceeds from notes payable, net of fees		29,400
Payments of revenue interesting financing debt	(421)
Net cash provided by financing activities	63	31,147
Net decrease in cash and cash equivalents	(112,764)	(30,601)
Cash and cash equivalents-beginning of period	240,551	122,927
Cash and cash equivalents-end of period	127,787	92,326
Supplemental disclosure of cash flow information
Unrealized loss on short-term investments	(114)
Debt issuance costs included in accrued expenses		563
Property and equipment in accrued expenses		1,198
Cash paid for interest during the period	4,336	3,484
Cash paid for income taxes during the period	$ 163
Property and equipment in deposits placed in service		$ 1,665