Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 17,765	$ 15,294
Short-term investments	22,850	22,276
Prepaid expenses and other current assets	2,111	1,345
Total current assets	42,726	38,915
Right-of-use asset	965
Other assets	143	254
Total assets	43,834	39,169
Current liabilities:
Accounts payable	2,156	1,408
Accrued expenses	2,476	2,763
Current portion of operating lease liabilities	929
Total current liabilities	5,561	4,171
Other long-term liabilities		56
Total liabilities	5,561	4,227
Commitments (Note 6)
Stockholders' equity:
Preferred stock, $0.001 par value per share, 5,000,000 shares authorized and no shares issued and outstanding
Common stock, $0.001 par value per share, 150,000,000 shares authorized; 11,715,286 and 7,141,996 shares issued and outstanding at September 30, 2019 and December 31, 2018, respectively	12	7
Additional paid-in capital	255,248	232,243
Accumulated other comprehensive loss		(4)
Accumulated deficit	(216,987)	(197,304)
Total stockholders' equity	38,273	34,942
Total liabilities and stockholders' equity	$ 43,834	$ 39,169

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).