CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 29,077	$ 36,559
Prepaid expenses and other current assets	3,000	4,383
Total current assets	32,077	40,942
Property and equipment, net	48	64
Right-of-use lease asset	161	30
Non-current deposits	3,060	1,551
Total assets	35,346	42,587
Current liabilities:
Accounts payable	2,205	2,117
Accrued and other current liabilities	2,821	3,177
Total current liabilities	5,026	5,294
Lease liability	113	30
Total liabilities	5,139	5,324
Stockholders' equity:
Common stock, $0.001 par value; 100,000,000 shares authorized at December 31, 2021 and June 30, 2022; 11,350,289 and 9,993,135 shares issued and outstanding at June 30, 2022 and December 31, 2021 respectively.	11	10
Additional paid-in capital	425,114	422,960
Accumulated other comprehensive loss	(1,276)	(748)
Accumulated deficit	(393,642)	(384,959)
Total stockholders' equity	30,207	37,263
Total liabilities and stockholders' equity	35,346	42,587
6% convertible exchangeable preferred stock
Stockholders' equity:
Preferred stock, $0.001 par value; 5,000,000 shares authorized at December 31, 2021 and June 30, 2022;	0	0
Series A Convertible Preferred Stock
Stockholders' equity:
Preferred stock, $0.001 par value; 5,000,000 shares authorized at December 31, 2021 and June 30, 2022;	0	0
Series B Convertible Preferred Stock
Stockholders' equity:
Preferred stock, $0.001 par value; 5,000,000 shares authorized at December 31, 2021 and June 30, 2022;	$ 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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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).