CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED C SHARES AND SHAREHOLDERS' EQUITY (DEFICIT) - USD ($)	Total	Vector Neurosciences Acquisition [Member]	IPO [Member]	Ordinary shares [Member]	Ordinary shares [Member] Vector Neurosciences Acquisition [Member]	Ordinary shares [Member] IPO [Member]	Capital in Excess of Nominal Value [Member]	Capital in Excess of Nominal Value [Member] Vector Neurosciences Acquisition [Member]	Capital in Excess of Nominal Value [Member] IPO [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Accumulated Deficit [Member]	Convertible Preferred C Shares [Member]	Convertible Preferred C Shares [Member] Accounts Payable [Member]	Convertible Preferred C Shares [Member] License Agreement [Member]	Convertible Preferred C Shares [Member] Sales Agreement [Member]
Temporary equity, beginning Balance at Dec. 31, 2016												$ 32,833,660
Beginning Balance at Dec. 31, 2016	$ (17,139,083)			$ 342			$ 17,900,995			$ (661,112)	$ (34,379,308)
Temporary equity, beginning Balance, Shares at Dec. 31, 2016												1,574,739
Beginning Balance, Shares at Dec. 31, 2016				8,818,461
Exercised stock options	$ 9,950						9,950
Exercised stock options, shares	1,288			1,288
Issuance of A ordinary shares in connection with a license agreement	$ 17,000						17,000
Issuance of A ordinary shares in connection with a license agreement, shares				6,441
Extinguishment of convertible preferred C shares, net of unaccreted issuance costs	33,115,157						33,115,157					$ (33,115,157)
Extinguishment of convertible preferred C shares, net of unaccreted issuance costs, shares												(1,584,469)
Issuance of convertible preferred C shares in connection with extinguishment	(33,206,360)						(33,206,360)					$ 33,206,360
Issuance of convertible preferred C shares in connection with extinguishment, shares												3,168,929
Conversion of convertible preferred C shares into A ordinary shares												$ 2,500,000
Conversion of convertible preferred C shares into A ordinary shares, shares												238,579
Issuance of convertible preferred C shares, net of warrants and issuance costs												$ 15,198,008
Issuance of convertible preferred C shares, net of warrants and issuance costs, shares												1,608,157
Accretion of issuance costs on convertible preferred C shares	(100,760)						(100,760)
Accretion of warrants issued in connection with convertible preferred C shares	(615,000)						(615,000)
Accretion of issuance costs on convertible preferred C shares												$ 100,760
Accretion of warrants issued in connection with convertible preferred C shares												615,000
Share-based compensation	2,959,731						2,959,731
Foreign currency translation, net of income taxes	(1,361,365)									(1,361,365)
Net loss	(31,044,535)										(31,044,535)
Temporary equity, beginning Balance at Dec. 31, 2017												$ 51,338,631
Ending Balance at Dec. 31, 2017	$ (47,365,265)			$ 342			20,080,713			(2,022,477)	(65,423,843)
Temporary equity, beginning Balance, Shares at Dec. 31, 2017	5,005,935											5,005,935
Ending Balance, Shares at Dec. 31, 2017				8,826,190
Issuance of convertible preferred C shares, net of issuance costs													$ 1,356,129	$ 140,000	$ 56,159,119
Sale of ordinary shares in initial public offering, net of issuance costs			$ 65,192,378			$ 194			$ 65,192,184
Issuance of shares, net of issuance costs, shares						5,000,000							129,419	13,360	5,425,124
Conversion of convertible preferred C shares into A ordinary shares	$ 120,520,391			$ 446			120,519,945					$ (120,520,391)
Conversion of convertible preferred C shares into A ordinary shares, shares				11,501,432								(11,501,432)
Accretion of issuance costs on convertible preferred C shares	(761,012)						(761,012)
Accretion of warrants issued in connection with convertible preferred C shares	(1,045,500)						(1,045,500)
Accretion of issuance costs on convertible preferred C shares												$ 761,012
Accretion of warrants issued in connection with convertible preferred C shares												1,045,500
Exercise of warrants	4,194,408						4,194,408					$ 9,720,000
Exercise of warrants, Share												927,594
Issuance of ordinary shares in connection with Vector Neurosciences acquisition		$ 2,990,250			$ 9			$ 2,990,241
Issuance of ordinary shares in connection with Vector Neurosciences acquisition, Shares					202,500
Share-based compensation	17,883,554			$ 73			17,883,481
Share-based compensation, Shares				1,856,510
Foreign currency translation, net of income taxes	2,316,143									2,316,143
Net loss	(82,865,874)										(82,865,874)
Ending Balance at Dec. 31, 2018	$ 81,059,473			$ 1,064			$ 229,054,460			$ 293,666	$ (148,289,717)
Temporary equity, beginning Balance, Shares at Dec. 31, 2018	0
Ending Balance, Shares at Dec. 31, 2018				27,386,632