CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 18,345	$ 36,559
Prepaid expenses and other current assets	6,066	4,383
Total current assets	24,411	40,942
Property and equipment, net	32	64
Right-of-use lease asset	142	30
Non-current deposits	3,465	2,100
Total assets	28,050	43,136
Current liabilities:
Accounts payable	2,561	2,117
Accrued and other current liabilities	4,950	3,296
Total current liabilities	7,511	5,413
Lease liability	106	30
Total liabilities	7,617	5,443
Redeemable common stock, $0.001 par value, 3,117,100 and 0 shares issued and outstanding at December 31, 2021 and December 31, 2022 (Note 11).	4,494	0
Stockholders' equity:
Preferred stock, value
Common stock, $0.001 par value; 100,000,000 shares authorized at December 31, 2022 and December 31, 2021; 9,422,089 and 9,993,135 shares issued and outstanding at December 31, 2022 and December 31, 2021	9	10
Additional paid-in capital	422,973	422,960
Accumulated other comprehensive loss	(1,316)	(748)
Accumulated deficit	(405,727)	(384,529)
Total stockholders' equity	15,939	37,693
Total liabilities and stockholders' equity	28,050	43,136
6% convertible exchangeable preferred stock
Stockholders' equity:
Preferred stock, value	0	0
Series A Convertible Preferred Stock
Stockholders' equity:
Preferred stock, value	0	0
Series B Convertible Preferred Stock
Stockholders' equity:
Preferred stock, value	$ 0	$ 0

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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- 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).