Consolidated Balance Sheets - USD ($)	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 71,404,000	$ 63,617,000
Marketable securities	0	79,402,000
Accounts receivable	19,967,000	8,206,000
Receivable due from Roche	10,159,000	2,007,000
Inventory	13,171,000	10,438,000
Prepaid expenses and other current assets	9,118,000	5,251,000
Total current assets	123,819,000	168,921,000
Property and equipment, net	41,119,000	41,486,000
Restricted cash	2,305,000	1,395,000
Other assets	1,760,000	2,233,000
Total assets	169,003,000	214,035,000
Current liabilities:
Accounts payable	21,926,000	11,898,000
Accrued expenses and other current liabilities	36,745,000	20,578,000
Deferred revenue	2,212,000	2,104,000
Roche related-party deferred revenue	3,742,000	3,747,000
Current portion of deferred rent	1,818,000	2,324,000
Total current liabilities	66,443,000	40,651,000
Deferred rent, net of current portion and other non-current liabilities	10,892,000	8,538,000
Indebtedness to Roche - non-current	60,000,000
Commitments and contingencies (Note 12)
Stockholders’ equity:
Common stock, $0.0001 par value, 150,000,000 shares authorized; 36,541,770 and 35,281,001 shares issued and outstanding at December 31, 2017 and 2016, respectively	4,000	4,000
Additional paid-in capital	537,904,000	509,664,000
Accumulated other comprehensive loss	109,000	(14,000)
Accumulated deficit	(506,349,000)	(344,808,000)
Total stockholders’ equity	31,668,000	164,846,000
Total liabilities and stockholders’ equity	$ 169,003,000	$ 214,035,000