Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 47,046	$ 70,016
Prepaid expenses and other current assets	2,313	955
Total current assets	49,359	70,971
Other assets	90	90
Total assets	49,449	71,061
Current liabilities:
Accounts payable	56,665	44,698
Accrued expenses	14,395	19,882
Long-term debt, current portion	2,839
Deferred revenue	3,091	4,145
Total current liabilities	76,990	68,725
Non-current liabilities:
Deferred revenue		1,018
Long-term debt, net of current portion	22,547	25,006
Total liabilities	99,537	94,749
Stockholders’ deficit:
Common stock, $0.001 par value: 225,000,000 shares authorized at June 30, 2022 and December 31, 2021; 71,242,938 and 64,027,629 shares issued and outstanding at June 30, 2022 and December 31, 2021, respectively	71	64
Additional paid-in capital	612,347	587,327
Accumulated deficit	(662,506)	(611,079)
Total stockholders’ deficit	(50,088)	(23,688)
Total liabilities and stockholders’ deficit	$ 49,449	$ 71,061

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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Namespace Prefix:	us-gaap_
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).