Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 62,070	$ 68,454
Marketable securities	189,085	445,733
Prepaid expenses	8,593	6,718
Acquisition holdback amount placed in escrow	25,000	0
Other current assets	2,491	11,825
Total current assets	287,239	532,730
Property and equipment, net	9,424	2,870
Operating lease right-of-use assets	7,774
Indefinite-lived intangible asset	102,500	102,500
Goodwill	6,234	6,234
Other noncurrent assets	1,079	3,997
Total assets	414,250	648,331
Current liabilities:
Accounts payable	7,979	7,989
Accrued clinical trial expenses	18,666	10,621
Other Accrued Liabilities, Current	11,451	7,465
Acquisition holdback liability	24,444	0
Deferred revenue, current	5,927	0
Current portion of operating lease liabilities	1,322
Current portion of contingent consideration	25,600	32,300
Total current liabilities	95,389	58,375
Deferred revenue, noncurrent	7,425	0
Operating lease liabilities, net of current portion	10,752
Contingent consideration, net of current portion	38,200	45,900
Deferred tax liability	17,425	17,425
Deferred rent and lease incentive obligation		3,830
Total liabilities	169,191	125,530
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $.001 par value; 10,000 shares authorized, none issued and outstanding	0	0
Common stock, $.001 par value; 100,000 and 50,000 shares authorized and 45,272 and 42,078 shares issued and outstanding at December 31, 2019 and 2018, respectively	45	42
Additional paid-in capital	1,360,092	1,218,710
Accumulated other comprehensive income	379	3
Accumulated deficit	(1,115,457)	(695,954)
Total stockholders’ equity	245,059	522,801
Total liabilities and stockholders’ equity	$ 414,250	$ 648,331