Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 79,717	$ 194,494
Marketable securities	26,620	34,982
Accounts receivable, net	3,890
Inventory	89
Prepaid expenses and other, current	9,281	6,998
Total current assets	119,597	236,474
Property and equipment, net	4,714	5,153
Prepaid expenses and other, long-term	3,851	6,846
Intangible assets, net	49,379
Restricted cash	4,317	4,317
Total assets	181,858	252,790
Current liabilities:
Accounts payable	17,644	20,035
Accrued expenses	79,608	17,426
Total current liabilities	97,252	37,461
Deferred rent	5,438	5,505
Total liabilities	102,690	42,966
Commitments and contingencies (Note 8)
Stockholders' equity:
Common stock - $.0001 par value; 100,000,000 shares authorized; 37,384,975 shares issued and outstanding at September 30, 2017 and 36,826,010 issued and outstanding at December 31, 2016	4	4
Additional paid-in capital	1,109,212	1,006,344
Receivable from exercise of stock options	(5,653)
Accumulated other comprehensive loss	(7)	(13)
Accumulated deficit	(1,024,388)	(796,511)
Total stockholders' equity	79,168	209,824
Total liabilities and stockholders' equity	$ 181,858	$ 252,790

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

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.