Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 43,337	$ 49,331
Marketable securities	38,669	68,735
Tax incentive receivable	235	1,536
Prepaid expenses and other current assets	1,202	1,728
Total current assets	83,443	121,330
Property and equipment, net	913	375
Operating lease right-of-use assets	7,172
Restricted cash	1,339
Other assets	20	57
Total assets	92,887	121,762
Current liabilities:
Accounts payable	3,319	3,590
Accrued expenses	1,719	4,261
Accrued restructuring costs	3,619
Operating lease liabilities, current	409
Notes payable, current	7,273	5,455
Total current liabilities	16,339	13,306
Notes payable, long-term	10,166	15,185
Operating lease liabilities	6,502
Total liabilities	33,007	28,491
Commitments and contingencies (Note 7)
Stockholders' equity:
Preferred stock; $0.001 par value per share; 5,000,000 shares authorized as of September 30, 2019 and December 31, 2018; no shares issued and outstanding as of September 30, 2019 and December 31, 2018
Common stock, $0.001 par value per share; 115,000,000 shares authorized as of September 30, 2019 and December 31, 2018; 37,370,301 and 37,287,221 shares issued and outstanding as of September 30, 2019 and December 31, 2018, respectively	37	37
Additional paid-in capital	448,902	444,212
Accumulated deficit	(389,100)	(350,945)
Accumulated other comprehensive income (loss)	41	(33)
Total stockholders' equity	59,880	93,271
Total liabilities and stockholders' equity	$ 92,887	$ 121,762

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).