Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 76,814	$ 63,617
Marketable securities		79,402
Accounts receivable	13,293	8,206
Receivable due from Roche	2,203	2,007
Inventory	10,400	10,438
Prepaid expenses and other current assets	4,612	5,251
Total current assets	107,322	168,921
Property and equipment, net	39,136	41,486
Restricted cash	2,305	1,395
Other assets	1,796	2,233
Total assets	150,559	214,035
Current liabilities:
Accounts payable	16,178	11,898
Accrued expenses and other current liabilities	28,246	20,578
Deferred revenue	1,702	2,104
Roche related-party deferred revenue	296	3,747
Current portion of deferred rent	1,439	2,324
Total current liabilities	47,861	40,651
Deferred rent, net of current portion and other non-current liabilities	9,261	8,538
Indebtedness to Roche - non-current	30,000
Commitments and contingencies (Note 15)
Stockholders’ equity:
Common stock, $0.0001 par value, 150,000,000 shares authorized; 36,158,558 and 35,281,001 shares issued and outstanding at September 30, 2017 and December 31, 2016, respectively	4	4
Additional paid-in capital	531,593	509,664
Accumulated other comprehensive income (loss)	78	(14)
Accumulated deficit	(468,238)	(344,808)
Total stockholders’ equity	63,437	164,846
Total liabilities and stockholders’ equity	$ 150,559	$ 214,035