Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Operating expenses:
Research and development	$ 6,654,257	$ 10,694,029	$ 13,418,105	$ 19,790,151
General and administrative	3,343,325	3,786,886	6,769,158	6,563,354
Total operating expenses	9,997,582	14,480,915	20,187,263	26,353,505
Other income (expense):
Interest (expense) income, net	(588)	2,678	(1,645)	227,120
Foreign currency (loss) gain	(252,843)	(1,889,690)	269,140	358,201
Total other (expense) income	(253,431)	(1,887,012)	267,495	585,321
Net loss	(10,251,013)	(16,367,927)	(19,919,768)	(25,768,184)
Other comprehensive loss:
Foreign currency translation	193,020	1,756,783	(209,830)	(667,870)
Total comprehensive loss	$ (10,057,993)	$ (14,611,144)	$ (20,129,598)	$ (26,436,054)
Net loss per share attributable to common stockholders, basic and diluted (in dollars per share)	$ (0.48)	$ (0.78)	$ (0.94)	$ (1.22)
Weighted-average common shares outstanding, basic and diluted (in shares)	21,186,827	21,107,056	21,186,827	21,079,891