Share-based Compensation (Tables)

12 Months Ended

Dec. 31, 2017

Schedule of Assumptions Used to Estimate Fair Values of Share Options Granted

The following table presents the assumptions used to estimate the fair values of the share options granted in the years presented:

	March 2015			October 2015			March 2016			August 2016			December 2016			May 2017			September 2017
Risk-free rate    of return		3.1	%		3.1	%		2.8	%		2.5	%		3.4	%		3.2	%		3.5	%
Contractual life    of option	10 years			10 years			10 years			10 years			10 years			10 years			10 years
Estimated    volatility rate		70	%		70	%		70	%		70	%		70	%		70	%		70	%
Expected    dividend    yield		0	%		0	%		0	%		0	%		0	%		0	%		0	%
Fair value of    underlying    ordinary    shares		1.62			1.92			7.14			8.04			8.04			9.60			27.93

Summary of Option Activity

A summary of option activity under the Plan during the years ended December 31, 2015, 2016 and 2017 is presented below:

	Number of options			Weighted average exercise price		Weighted average remaining contractual term		Aggregate intrinsic value
				$		Years		$
Outstanding at January 1, 2015		—			—		—		—
Granted		4,309,232			0.60		—		—
Outstanding at December 31, 2015		4,309,232			0.60		9.68		18,874,438
Granted		2,918,993			1.53		—		—
Forfeited		(84	)		1.74		—		—
Outstanding at December 31, 2016		7,228,141			0.97		9.00		53,677,170
Granted		264,480			8.76		—		—
Exercised		(100,834	)		0.65		—		—
Forfeited		(843,410	)		1.11		—		—
Outstanding at December 31, 2017		6,548,377			1.28		8.06		130,668,851
Vested and Exercisable as of December 31,    2017		2,307,319			0.80		7.84		47,134,503
Vested or expected to vest as of December 31,    2017		6,548,377			1.28		8.06		130,668,851

Allocation of Compensation Expense Related to Option

The weighted-average grant-date fair value of the options granted in 2015, 2016 and 2017 were $1.62, $6.94 and $13.92 per share, respectively. The Group recorded compensation expense related to the options of $419,709, $3,524,733 and $4,751,933 for the year ended December 31, 2015, 2016 and 2017, respectively, which were classified in the accompanying consolidated statements of operations as follows:

	Year ended December 31,
	2015		2016		2017
	$		$		$
General and administrative		124,871		1,472,993		2,215,282
Research and development		294,838		2,051,740		2,536,651
Total		419,709		3,524,733		4,751,933

Summary of Non-vested Restricted Share Activity

The following table summarized the Group’s non-vested restricted share activity in 2017:

	Numbers of non-vested restricted shares			Weighted average grant date fair value
				$
Non-vested as of January 1, 2017		2,309,490			1.31
Granted		50,000			27.93
Vested		(2,309,490	)		1.03
Transferred from Red Kingdom		643,333			0.60
Non-vested as of December 31, 2017		693,333			2.57

Allocation of Compensation Expense Related to Restricted Shares

As of December 31, 2017, there was $1,517,160 of total unrecognized compensation expense related to non-vested Restricted Shares. The Group recorded compensation expense related to the restricted shares of $2,281,695, $1,400,545 and $5,179,173 for the year ended December 31, 2015, 2016 and 2017, respectively, which were classified in the accompanying consolidated statements of operations as follows:

	Year ended December 31,
	2015		2016		2017
	$		$		$
General and administrative		964,012		825,822		3,848,165
Research and development		1,317,683		574,723		1,331,008
Total		2,281,695		1,400,545		5,179,173

Red Kingdom

Summary of Non-vested Restricted Share Activity

The following table summarized the non-vested restricted shares activities of Red Kingdom in 2017:

	Numbers of non-vested restricted shares			Weighted average grant date fair value
				$
Non-vested as of January 1, 2017		2,784,999			0.60
Vested		(811,667	)		0.60
Forfeited		(1,329,999	)		0.60
Transferred to the Company		(643,333	)		0.60
Non-vested as of December 31, 2017		—