Share-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of Company's Share Option Activity Related to Employees, Non-Employee Members of the Board of Directors and Non-Employee Consultants

A summary of the Company’s share option activity related to employees, non-employee members of the board of directors and non-employee consultants as of and for the years ended December 31, 2018 and 2017 is as follows:

STOCK OPTION TABLE

	Number of Options			Weighted- Average Exercise Price			Aggregate Instrinsic Value
Outstanding at December 31, 2016		333,660		$	7.72
Granted		611,933			3.73
Exercised		(1,288	)		(7.57	)
Expired		—			—
Forfeited		(5,668	)		(7.72	)
Outstanding at December 31, 2017		938,637		$	5.12
Granted		2,334,285			8.63
Exercised		—			—
Expired		—			—
Forfeited		(10,557	)		(5.51	)
Outstanding at December 31, 2018		3,262,365		$	7.64		$	6,903,313
Weighted average remaining contractual life of options outstanding as of December 31, 2017 (yrs)		9.09
Weighted average remaining contractual life of options outstanding as of December 31, 2018 (yrs)		9.24
Options exercisable at December 31, 2017		186,394		$	7.72
Options exercisable at December 31, 2018		535,241		$	5.79
Weighted average remaining contractual life of options exercisable as of December 31, 2017 (yrs)		8.21
Weighted average remaining contractual life of options exercisable as of December 31, 2018 (yrs)		7.88

Schedule of Grant Date Fair Values of the Stock Option Granted

The grant date fair values of the stock options granted were estimated using the Black-Scholes option valuation model with the following ranges of assumptions (see Note 2):

	2018	2017
Risk-free interest rate	2.32% - 2.98%	2.28% - 2.51%
Expected volatility	90%	80%
Expected dividend yield	0%	0%
Expected life (in years)	5.5 - 10.0	5.5 - 10.0

Summary of Restricted Ordinary Shares

A summary of the restricted Ordinary Shares is as follows:

	Ordinary Shares			$ Value
Non-vested at December 31, 2016		386,608		$	3,020,191
Vesting during 2017		(280,695	)		(2,154,330	)
Non-vested at December 31, 2017		105,913			865,861
Issued during 2018		1,306,348			19,595,220
Vesting during 2018		(759,087	)		(10,663,471	)
Non-vested at December 31, 2018		653,174		$	9,797,610

Schedule of Share Based Compensation Expense

During the years ended December 31, 2018 and 2017 the Company recognized total share-based compensation expense in the accompanying consolidated statements of operations and comprehensive loss as follows:

	2018		2017
Research and development	$	3,372,054	$	2,374,899
General and administrative		14,511,500		584,832
Total share based compensation	$	17,883,554	$	2,959,731