CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Total revenues	$ 1,535	$ 2,474	$ 1,639	$ 3,610
Operating expenses:
Research and development expenses	(28,401)	(24,154)	(54,414)	(44,691)
Selling, general and administrative expenses	(11,511)	(7,870)	(20,583)	(15,937)
Total operating expenses	(39,912)	(32,024)	(74,997)	(60,628)
Other income	669	566	1,526	879
Other expense	(500)	(347)	(839)	(696)
Loss from operations	(38,208)	(29,331)	(72,671)	(56,835)
Interest income	81	728	903	1,170
Interest expense	(970)	(937)	(1,945)	(1,894)
Foreign currency (losses) / gains, net	(3,645)	(1,252)	957	1,022
Other non-operating gains / (losses), net	191	(607)	2,206	(2,634)
Net loss	(42,551)	(31,399)	(70,550)	(59,171)
Other comprehensive income / (loss):
Foreign currency translation adjustments	4,647	1,209	(630)	(1,259)
Total comprehensive loss	$ (37,904)	$ (30,190)	$ (71,180)	$ (60,430)
Basic and diluted net loss per ordinary share	$ (0.96)	$ (0.83)	$ (1.59)	$ (1.57)
Weighted average shares used in computing basic and diluted net loss per ordinary share	44,387,463	37,824,928	44,333,460	37,750,961
License revenues from related party
Total revenues	$ 1,530	$ 2,108	$ 1,577	$ 2,665
Collaboration revenues from related party
Total revenues	$ 5	$ 366	$ 62	$ 945