Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Current Assets
Cash and cash equivalents	$ 137,497	$ 182,069
Prepaid expenses	5,559	2,542
Other current assets	136
Total current assets	143,192	184,611
Other assets	611	327
Property and equipment, net	373	389
Total assets	144,176	185,327
Current liabilities
Accounts payable	732	1,671
Accrued liabilities	7,703	7,156
Total liabilities	8,435	8,827
Commitments and contingencies (Note 6)
Stockholders' equity
Common stock, $0.0001 par value, 50,000,000 shares authorized at June 30, 2016 and December 31, 2015; 29,541,214 and 29,420,247 shares issued and outstanding at June 30, 2016 and December 31, 2015, respectively	3	3
Additional paid-in capital	375,729	369,933
Accumulated other comprehensive loss	(206)
Accumulated deficit	(239,785)	(193,436)
Total stockholders' equity	135,741	176,500
Total liabilities and stockholders’ equity	$ 144,176	$ 185,327

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).