CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 22,299	$ 8,134
Research and development incentive receivable	1,552
Prepaid expenses and other current assets	2,372	1,205
Total current assets	26,223	9,339
Property and equipment, net	271	241
Intangible assets	4,900
Goodwill	27,407
Right-of-use assets	2,705
Restricted cash	947	364
Other assets	96
Total assets	62,549	9,944
Current liabilities:
Accounts payable	6,132	2,969
Accrued expenses	4,179	3,251
Current portion of lease liability	841
Current portion of long-term debt	5,298	1,687
Total current liabilities	16,450	7,907
Preferred stock warrant liability		4,947
Long-term debt, including accretion, net of discount and current portion	13,365	8,145
Deferred rent		417
Lease liability	3,275
Other liabilities	18	205
Total liabilities	33,108	21,621
Commitments and contingencies (Note 9)
Convertible preferred stock (Series Seed, A and B), $0.001 par value;10,000,000 and 59,413,523 shares authorized as of March 31, 2019 and December 31, 2018, respectively; 0 and 40,079,567 shares issued and outstanding as of March 31, 2019 and December 31, 2018, respectively		64,675
Common stock	7
Stockholders' equity (deficit):
Common stock	7
Additional paid-in capital	119,521	2,151
Accumulated other comprehensive income	23
Accumulated deficit	(90,110)	(79,237)
Total stockholders' equity (deficit)	29,441	(77,086)
Total liabilities, convertible preferred stock, redeemable common stock and stockholders' equity (deficit)	$ 62,549	9,944
Convertible Preferred Stock [Member]
Current liabilities:
Convertible preferred stock (Series Seed, A and B), $0.001 par value;10,000,000 and 59,413,523 shares authorized as of March 31, 2019 and December 31, 2018, respectively; 0 and 40,079,567 shares issued and outstanding as of March 31, 2019 and December 31, 2018, respectively		64,675
Redeemable Common Stock [Member]
Current liabilities:
Common stock		734
Stockholders' equity (deficit):
Common stock		734
Total stockholders' equity (deficit)		$ 734

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).