Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents	$ 182,069	$ 170,566
Prepaid expenses and other current assets	2,542	2,398
Total current assets	184,611	172,964
Other assets	327	616
Property and equipment, net	389	714
Total assets	185,327	174,294
Current liabilities
Accounts payable	1,671	1,259
Accrued liabilities	7,156	5,666
Total liabilities	$ 8,827	$ 6,925
Commitments and contingencies (Note 7)
Stockholders' equity
Preferred stock, $0.0001 par value, 5,000,000 shares authorized at December 31, 2015 and December 31, 2014; zero shares issued and outstanding at December 31, 2015 and December 31, 2014
Common stock, $0.0001 par value, 50,000,000 shares authorized at December 31, 2015 and December 31, 2014; 29,420,247 and 24,245,437 shares issued and outstanding at December 31, 2015 and December 31, 2014, respectively	$ 3	$ 2
Additional paid-in capital	369,933	278,626
Accumulated deficit	(193,436)	(111,259)
Total stockholders' equity	176,500	167,369
Total liabilities and stockholders’ equity	$ 185,327	$ 174,294

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).