Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2019		Sep. 30, 2018
Operating activities
Net loss	$ (75,150)		$ (63,436)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation expense	1,993		2,005
Amortization of deferred financing costs	550		144
Amortization of deferred compensation for services	231		177
Amortization of premium on investment securities	(666)		(708)
Non-cash lease expense	1,356
Stock-based compensation	7,724		6,976
Change in derivative liabilities	246		56
Non-cash interest associated with debt discount accretion	353		164
Changes in operating assets and liabilities:
Accounts receivable and unbilled license revenue	2,386		10,629
Prepaid expenses and other assets	(454)		(3,908)
Accounts payable	541		(1,609)
Accrued compensation and benefits	81		(923)
Lease liabilities	(1,301)
Accrued and other liabilities	(3,237)		(1,405)
Net cash used in operating activities	(65,347)		(51,838)
Investing activities
Proceeds from maturities of investments	114,484		95,450
Sales and redemptions of investments	1,000		850
Purchases of investments	(36,325)		(148,360)
Purchases of property and equipment	(325)		(24)
Net cash provided by (used in) investing activities	78,834		(52,084)
Financing activities
Proceeds from loan payable, net of issuance costs			49,292
Proceeds from underwritten public offering, net of issuance costs			53,770
Issuance of common stock upon exercise of options	21
Proceeds from issuance of common stock under stock plans	397		492
Net cash provided by financing activities	418		103,554
Net increase (decrease) in cash and cash equivalents	13,905		(368)
Cash and cash equivalents at beginning of period	78,768	[1]	75,383
Cash and cash equivalents at end of period	$ 92,673		75,015
Supplementary disclosure of non-cash financing information:
Issuance of derivative in connection with issuance of loan payable			$ 546

[1] Derived from the audited consolidated financial statements included in the Company’s Annual Report on Form 10K for the year ended December 31, 2018.