STOCK-BASED COMPENSATION (Tables)

3 Months Ended

Mar. 31, 2019

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

Schedule of fair values of stock options granted, estimated using Black-Scholes option valuation model assumptions

We estimated the fair value of stock options awarded during the three months ended March 31, 2019 and 2018 using the Black-Scholes option valuation model. The fair values of stock options granted for the periods were estimated using the following assumptions:  

	Stock Option Grants Awarded During the Three Months Ended March 31, 2019	Stock Option Grants Awarded During the Three Months Ended March 31, 2018
Stock Price	$1.52 to $2.98	$5.01 to $5.96
Dividend Yield	0.00%	0.00%
Expected Volatility	70%	70%
Risk-free interest rate	2.52% - 2.62%	2.50% - 2.61%
Expected Life	7 years	7 years

Summary of stock option activity

The following is a summary of our stock option activity during the three months ended March 31, 2019: 

	Number of Options		Weighted Average Exercise Price		Weighted Average Grant Date Fair Value		Weighted Average Remaining Life In Years
Outstanding, January 1, 2019	1,255,280		$	4.82	$	3.03	7.75
Granted	40,000		2.23		1.51		9.84
Exercised	—		—		—		—
Canceled / Forfeited	(1,252	)	4.62		2.79		—
Outstanding, March 31, 2019	1,294,028		$	4.74	$	2.98	7.57

	Number of Options		Weighted Average Exercise Price		Weighted Average Grant Date Fair Value		Weighted Average Remaining Life In Years
Exercisable, January 1, 2019	843,019		$	5.02	$	3.13	7.23
Vested	42,436		4.37		2.74		8.01
Exercised	—		—		—		—
Canceled / Forfeited	(1,252	)	4.62		2.79		—
Exercisable, March 31, 2019	884,203		$	4.99	$	3.11	7.04

Schedule of information related to stock options outstanding and exercisable

The following table presents information related to stock options outstanding and exercisable at March 31, 2019: 

Options Outstanding		Options Exercisable
Exercise Price	Outstanding Number of Options	Weighted Average Remaining Life In Years	Exercisable Number of Options
$1.52 – $3.00	201,183	6.87	109,889
$3.25 – $4.92	651,045	8.21	413,854
$5.01 – $6.00	281,500	5.70	220,775
$6.18 – $7.20	70,000	5.79	56,255
$7.54 – $7.80	67,800	5.88	60,930
$8.06 – $12.98	22,500	5.80	22,500
	1,294,028	7.04	884,203

Schedule of restricted stock unit activity

 A summary of restricted stock unit activity for the three months ended March 31, 2019 is as follows:

Schedule of stock-based compensation

Total stock-based compensation recorded in the condensed consolidated statements of comprehensive loss is allocated as follows: 

	Three Months Ended March 31, 2019		Three Months Ended March 31, 2018
Research and development	$	633,000	$	531,000
Sales, marketing and administration	721,000		432,000
Total stock-based compensation	$	1,354,000	$	963,000