Condensed Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Operating expenses:
Research and development	$ 8,683	$ 2,310	$ 26,727	$ 2,733
General and administrative	5,919	1,454	14,776	2,444
Total operating expenses	14,602	3,764	41,503	5,177
Loss from operations	(14,602)	(3,764)	(41,503)	(5,177)
Other income (expense), net:
Other income (expense), net	10		14
Related party convertible note interest expense				(40)
Change in fair value of the Series A redeemable convertible preferred stock tranche liability		380	(10,341)	380
Total other income (expense), net	10	380	(10,327)	340
Net loss and comprehensive loss	$ (14,592)	$ (3,384)	$ (51,830)	$ (4,837)
Net loss per share attributable to common stockholders—basic and diluted	$ (0.28)	$ (1.00)	$ (2.51)	$ (2.53)
Weighted-average shares used in computing net loss per share— basic and diluted	52,769,916	3,382,118	20,668,560	1,908,759

Change in fair value of redeemable convertible preferred stock tranche liability.

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Net income (loss) and comprehensive income (loss).

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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