10. Share-Based Expense (Tables)

3 Months Ended

12 Months Ended

Mar. 31, 2019

Dec. 31, 2018

Schedule of Share-Based Compensation Expense

	Three Months Ended March 31,
	2019		2018
Research and development expenses	$	11,418	$	60,345
General and administrative expenses		222,522		345,849
	$	233,940	$	406,194

	Year Ended December 31,
	2018		2017
Research and development expenses	$	203,030	$	101,401
General and administrative expenses		1,228,757		1,691,692
	$	1,431,787	$	1,793,093

Common Stock Awards [Member]

Common stock awards

	Number of shares
Balance as of January 1, 2017		2,483
Granted		3,484
Issued		(732	)
Balance as of December 31, 2017		5,235
Granted		2,167
Issued		–
Balance as of December 31, 2018		7.402

Employee Stock Options [Member]

Assumptions used

	Year Ended December 31,
	2018		2017
Weighted-average expected dividend yield (%)		–		–
Weighted-average expected volatility (%)		118.03		111.37
Weighted-average risk-free interest rate (%)		2.90		1.79
Weighted-average expected life of option (years)		5.90		5.36
Weighted-average exercise price ($)		36.60		40.08

Option activity

	Number of shares			Weighted- average exercise price		Weighted- average remaining life (years)		Aggregate intrinsic value
Outstanding as of January 1, 2017		99,476		$	53.16		8.94	$	526,073
Granted		58,334			40.08
Expired		(9,446	)		55.32
Outstanding as of December 31, 2017		148,364			47.88		8.53	$	5,273
Granted		8,334			36.60
Expired		(9,245	)		68.76
Outstanding as of December 31, 2018		147,453		$	45.96		8.17	$	–
Vested or expected to vest as of December 31, 2018		145,370		$	46.20		8.16	$	–
Exercisable as of December 31, 2017		60,992		$	58.08		7.44	$	5,273
Exercisable as of December 31, 2018		96,015		$	49.32		7.92	$	–

Non-vested option activity

	Number of shares			Weighted- average grant date fair value
Balance as of January 1, 2018		87,373		$	34.32
Granted		8,334		$	31.56
Forfeited		(556	)	$	34.92
Vested		(43,712	)	$	36.60
Balance as of December 31, 2018		51,439		$	31.80

Non Employee Stock Options [Member]

Option activity

	Number of shares			Weighted- average exercise price		Weighted- average remaining life (years)		Aggregate intrinsic value
Outstanding as of January 1, 2017		4,787		$	90.84		7.23	$	–
Expired		(61	)		124.08
Outstanding as of December 31, 2017		4,726			90.36		6.31	$	–
Granted		834			23.16
Expired		(263	)		219
Outstanding as of December 31, 2018		5,297		$	73.44		5.40	$	–
Vested or expected to vest as of December 31, 2018		5,297		$	73.44		5.40	$	–
Exercisable as of December 31, 2017		4,727		$	90.36		6.31	$	–
Exercisable as of December 31, 2018		5,297		$	73.44		5.40	$	–

Non-vested option activity

	Number of shares			Weighted- average grant date fair value
Balance as of January 1, 2018		–		$	–
Granted		834		$	20.76
Vested		(834	)	$	20.76
Balance as of December 31, 2018		–		$	–