Condensed Consolidated Balance Sheets (unaudited) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 44,967	$ 88,254
Marketable securities	23,134
Prepaid expenses and other current assets	2,391	2,195
Total current assets	70,492	90,449
Restricted cash	140	140
Property and equipment, net	1,238	1,097
Operating lease right-of-use asset	1,981
Other assets	4,424	503
Total assets	78,275	92,189
Current liabilities:
Accounts payable	2,529	1,050
Accrued and other current liabilities	3,277	3,776
Operating lease liability	408
Total current liabilities	6,214	4,826
Operating lease liability, net of current portion	1,725
Other liabilities	317	530
Total liabilities	8,256	5,356
Commitments and contingencies (Note 6)
Stockholders’ equity:
Common stock, $0.0001 par value, 490,000,000 shares authorized at June 30, 2019 and December 31, 2018; 36,931,141 and 36,829,857 shares issued and outstanding at June 30, 2019 and December 31, 2018, respectively	4	4
Additional paid-in capital	200,138	197,595
Accumulated other comprehensive loss	12
Accumulated deficit	(130,135)	(110,766)
Total stockholders’ equity	70,019	86,833
Total liabilities and stockholders’ equity	$ 78,275	$ 92,189

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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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).