Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 131,777	$ 24,930
Short-term investments		20,000
Prepaid expenses and other current assets	2,745	1,395
Total current assets	134,522	46,325
Right-of-use asset	557	966
Other assets	50	165
Total assets	135,129	47,456
Current liabilities:
Accounts payable	574	1,544
Accrued expenses	3,585	4,197
Current portion of operating lease liabilities	541	649
Total current liabilities	4,700	6,390
Long-term portion of operating lease liabilities		397
Total liabilities	4,700	6,787
Stockholders' equity:
Series X redeemable convertible preferred stock, $0.001 par value per share, 36,758 shares authorized; 31,455 shares issued and outstanding as of September 30, 2021 and no shares issued and outstanding as of December 31, 2020	96,398
Common stock, $0.001 par value per share, 150,000,000 shares authorized; 13,009,477 and 3,347,389 shares issued and outstanding at September 30, 2021 and December 31, 2020, respectively	13	3
Additional paid-in capital	480,336	301,563
Accumulated deficit	(446,318)	(260,897)
Total stockholders' equity	130,429	40,669
Total liabilities and stockholders' equity	$ 135,129	$ 47,456

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).