CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 23,910	$ 16,520
Prepaid expenses and other current assets	2,064	3,097
Total current assets	25,974	19,617
Property and equipment, net	29	45
Total assets	26,003	19,662
Current liabilities:
Accounts payable	1,558	2,497
Accrued and other current liabilities	2,555	2,762
Total current liabilities	4,113	5,259
Other liabilities	124	130
Total liabilities	4,237	5,389
Commitments and contingencies (Note 9)
Stockholders' equity:
Preferred stock, value
Common stock, $0.001 par value; 100,000,000 shares authorized at December 31, 2016 and December 31, 2017; 4,256,829 and 11,997,447 shares issued and outstanding at December 31, 2016 and December 31, 2017, respectively.	12	4
Additional paid-in capital	365,057	350,051
Accumulated other comprehensive loss	(794)	(743)
Accumulated deficit	(342,509)	(335,039)
Total stockholders' equity	21,766	14,273
Total liabilities and stockholders' equity	26,003	19,662
Series A convertible preferred stock
Stockholders' equity:
Preferred stock, value	0	0
6% Convertible Exchangeable 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).