CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 20,229	$ 77,383
Marketable securities	102,557
Prepaid expenses and other current assets	2,722	3,123
Total current assets	125,508	80,506
Property and equipment, net	3,073	3,707
Other assets	389	389
Total assets	128,970	84,602
Current liabilities:
Accounts payable	4,405	1,143
Accrued expenses	5,669	3,642
Deferred revenue, current	5,128	4,000
Other current liabilities	389	471
Total current liabilities	15,591	9,256
Deferred rent, net of current portion	2,200	2,225
Deferred revenue, non-current	1,132
Commitments
Stockholders' equity:
Preferred stock
Common stock	2	2
Additional paid-in capital	312,078	235,049
Accumulated other comprehensive income	74	20
Accumulated deficit	(202,107)	(161,950)
Total stockholders' equity	110,047	73,121
Total liabilities and stockholders' equity	$ 128,970	$ 84,602

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).

Name:	us-gaap_AccountsPayableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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).