Condensed Statements of Stockholders’ Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Balance, beginning (in shares) at Dec. 31, 2021		8,491,494
Balance, beginning at Dec. 31, 2021	$ 142,864		$ 536,362		$ (393,498)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued upon exercises of stock options (in shares)		7,300
Shares issued upon exercises of stock options	134		134
Stock-based compensation	2,446		2,446
Net loss	(15,351)				(15,351)
Balance, ending (in shares) at Mar. 31, 2022		8,498,794
Balance, ending at Mar. 31, 2022	130,093		538,942		(408,849)
Balance, beginning (in shares) at Dec. 31, 2021		8,491,494
Balance, beginning at Dec. 31, 2021	$ 142,864		536,362		(393,498)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued upon exercises of stock options (in shares)	7,300
Unrealized gain (loss) on available-for-sale securities	$ (92)
Net loss	(44,112)
Balance, ending (in shares) at Sep. 30, 2022		8,518,920
Balance, ending at Sep. 30, 2022	105,647		543,348	$ (92)	(437,609)
Balance, beginning (in shares) at Mar. 31, 2022		8,498,794
Balance, beginning at Mar. 31, 2022	130,093		538,942		(408,849)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of shares under Employee Stock Purchase Plan (in shares)		15,176
Issuance of shares under Employee Stock Purchase Plan	63		63
Shares issued upon vesting of restricted stock units (in shares)		2,000
Stock-based compensation	2,312		2,312
Unrealized gain (loss) on available-for-sale securities	(72)			(72)
Net loss	(15,688)				(15,688)
Balance, ending (in shares) at Jun. 30, 2022		8,515,970
Balance, ending at Jun. 30, 2022	116,708		541,317	(72)	(424,537)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued upon vesting of restricted stock units (in shares)		2,950
Stock-based compensation	2,031		2,031
Unrealized gain (loss) on available-for-sale securities	(20)			(20)
Net loss	(13,072)				(13,072)
Balance, ending (in shares) at Sep. 30, 2022		8,518,920
Balance, ending at Sep. 30, 2022	105,647		543,348	(92)	(437,609)
Balance, beginning (in shares) at Dec. 31, 2022		8,529,668
Balance, beginning at Dec. 31, 2022	94,331		545,407	(21)	(451,055)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued upon vesting of restricted stock units (in shares)		34,000
Stock-based compensation	1,191		1,191
Unrealized gain (loss) on available-for-sale securities	39			39
Net loss	(14,204)				(14,204)
Balance, ending (in shares) at Mar. 31, 2023		8,563,668
Balance, ending at Mar. 31, 2023	81,357		546,598	18	(465,259)
Balance, beginning (in shares) at Dec. 31, 2022		8,529,668
Balance, beginning at Dec. 31, 2022	$ 94,331		545,407	(21)	(451,055)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued upon exercises of stock options (in shares)	0
Unrealized gain (loss) on available-for-sale securities	$ 21
Net loss	(20,815)
Balance, ending (in shares) at Sep. 30, 2023		8,805,284
Balance, ending at Sep. 30, 2023	75,235		547,105	0	(471,870)
Balance, beginning (in shares) at Mar. 31, 2023		8,563,668
Balance, beginning at Mar. 31, 2023	81,357		546,598	18	(465,259)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued upon the exercise of pre-funded warrants (in shares)		236,000
Issuance of shares under Employee Stock Purchase Plan (in shares)		2,616
Issuance of shares under Employee Stock Purchase Plan	4		4
Shares issued upon vesting of restricted stock units (in shares)		2,000
Stock-based compensation	331		331
Unrealized gain (loss) on available-for-sale securities	(31)			(31)
Net loss	(2,085)				(2,085)
Balance, ending (in shares) at Jun. 30, 2023		8,804,284
Balance, ending at Jun. 30, 2023	79,576		546,933	(13)	(467,344)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued upon vesting of restricted stock units (in shares)		1,000
Stock-based compensation	172		172
Unrealized gain (loss) on available-for-sale securities	13			13
Net loss	(4,526)				(4,526)
Balance, ending (in shares) at Sep. 30, 2023		8,805,284
Balance, ending at Sep. 30, 2023	$ 75,235		$ 547,105	$ 0	$ (471,870)