Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Tables)

v3.10.0.1
Stock-Based Compensation (Tables)
6 Months Ended
Jun. 30, 2018
Summary of Activity under Stock Option Plan and Related Information

The following table summarizes activity under the Company’s stock option plan and related information (in thousands, except share and per share amounts):

 

 

 

Number of Options Outstanding

 

 

Weighted Average Exercise Price

 

 

Weighted Average Remaining Contractual Term

 

 

Aggregate Intrinsic Value

 

Outstanding at December 31, 2017

 

 

1,213,010

 

 

$

1.54

 

 

 

8.7

 

 

$

999

 

Additional shares authorized

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Options granted

 

 

1,111,901

 

 

$

5.77

 

 

 

 

 

 

 

 

 

Options exercised

 

 

(136,328

)

 

$

1.56

 

 

 

 

 

 

$

237

 

Options cancelled

 

 

(10,917

)

 

$

0.90

 

 

 

 

 

 

 

 

 

Outstanding at June 30, 2018

 

 

2,177,666

 

 

$

3.70

 

 

 

9.0

 

 

$

29,609

 

Options exercisable at June 30, 2018

 

 

535,218

 

 

$

1.46

 

 

 

7.8

 

 

$

8,478

 

 

 

Summarizes of Activity of Nonvested Restricted Stock

The following summarizes the activity of nonvested restricted stock:

 

 

 

Number of Shares

 

Nonvested—December 31, 2017

 

 

193,394

 

Vested

 

 

(104,537

)

Nonvested—June 30, 2018

 

 

88,857

 

 

Stock-Based Compensation Recognized

Total stock-based compensation recognized by function was as follows (in thousands):

 

 

 

Three Months Ended June 30,

 

 

Six Months Ended June 30,

 

 

 

2018

 

 

2017

 

 

2018

 

 

2017

 

General and administrative

 

$

558

 

 

$

20

 

 

$

625

 

 

$

41

 

Research and development

 

 

430

 

 

 

18

 

 

 

489

 

 

 

35

 

Total stock-based compensation expense

 

$

988

 

 

$

38

 

 

$

1,114

 

 

$

76

 

 

Unrecognized Stock-based Compensation Cost and Estimated Weighted Average Amortization Period

As of June 30, 2018, the unrecognized stock-based compensation cost and the estimated weighted average amortization period, using the straight-line attribution method, was as follows (dollars in thousands):

 

 

 

Unrecognized Compensation Cost

 

 

Weighted Average Remaining Amortization Period (Years)

 

Employee options

 

$

4,664

 

 

 

3.5

 

Nonemployee options

 

 

7

 

 

 

1.0

 

Total unrecognized stock-based compensation expense

 

$

4,671

 

 

 

 

 

 

Fair Value of Employee Stock Options Granted is Calculated Using Black Scholes Option Pricing Model with Weighted Average Assumptions

The fair value of the employee stock options granted is calculated using the Black-Scholes option-pricing model with the following weighted-average assumptions:

 

 

 

Three Months Ended June 30,

 

 

Six Months Ended June 30,

 

 

 

2018

 

 

2017

 

 

2018

 

 

2017

 

Expected term (years)

 

5.5 - 6.1

 

 

 

6.1

 

 

5.5 - 6.1

 

 

 

6.1

 

Expected volatility

 

 

82.8

%

 

 

82.5

%

 

82.0 - 82.8%

 

 

 

82.5

%

Risk-free interest rate

 

 

2.8

%

 

 

2.1

%

 

2.6 - 2.8%

 

 

 

2.1

%

Expected dividend yield

 

 

%

 

 

%

 

 

%

 

 

%

 

Restricted Stock Units  
Summarizes of Activity of Nonvested Restricted Stock

During the three and six months ended June 30, 2018, the Company granted RSUs to certain employees to receive 10,189 shares of common stock pursuant to the 2018 Plan with a weighted-average estimated grant-date fair value of $17.75 per share. These RSUs were fully vested on the grant date. The valuation for these RSUs totaled $181,000 and was recognized as stock-based compensation expense in June 2018. There were no RSUs granted during the three and six months ended June 30, 2017.

 

 

Number of RSUs Outstanding

 

 

Weighted Average Grant-Date Fair Price

 

Outstanding at December 31, 2017

 

 

 

 

 

 

 

RSUs granted

 

 

10,189

 

 

$

17.75

 

RSUs vested

 

 

(10,189

)

 

$

17.75

 

Outstanding at June 30, 2018