Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Revenues:
Total revenue	$ 26,024	$ 15,198	$ 82,472	$ 64,374
Cost and expenses:
Cost of sales	393	695	1,030	695
Research and development	101,672	82,561	304,646	247,515
Selling, general and administrative	33,019	31,104	97,200	82,287
Total cost and expenses	135,084	114,360	402,876	330,497
Loss from operations	(109,060)	(99,162)	(320,404)	(266,123)
Interest income	2,887	4,498	11,282	11,889
Net loss	$ (106,173)	$ (94,664)	$ (309,122)	$ (254,234)
Net loss per share – basic and diluted (in usd per share)	$ (1.81)	$ (1.63)	$ (5.27)	$ (4.45)
Weighted-average number of common shares used in computing net loss per share – basic and diluted (in usd per share)	58,803,534	58,033,386	58,661,607	57,158,492
Product revenue, net
Revenues:
Total revenue	$ 17,422	$ 4,465	$ 40,287	$ 4,465
Collaboration revenue – related party
Revenues:
Total revenue	5,516	8,732	32,414	42,478
Collaboration revenue – other
Revenues:
Total revenue	420	0	2,202	12,440
Royalty revenue – related party
Revenues:
Total revenue	$ 2,666	$ 2,001	$ 7,569	$ 4,991

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