v3.19.2
Stock-Based Compensation (Tables)
6 Months Ended
Jun. 30, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]  
Summary of Stock Option Activity

The following table summarizes the stock option activity during the six months ended June 30, 2019:

 

 

 

Stock

Option

Shares

 

 

Weighted Average

Exercise

Price

 

 

Weighted Average

Remaining

Contractual

Term (in Years)

 

 

Aggregate

Intrinsic

Value

 

Outstanding, January 1, 2019

 

 

3,351,132

 

 

$

3.73

 

 

 

8.24

 

 

$

142,788

 

Granted

 

 

4,622,428

 

 

 

1.86

 

 

 

 

 

 

 

 

 

Exercised

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Expired/cancelled

 

 

(1,201,753

)

 

 

2.80

 

 

 

 

 

 

 

 

 

Outstanding, June 30, 2019

 

 

6,771,807

 

 

$

2.62

 

 

 

8.65

 

 

$

17,133

 

Expected to vest, June 30, 2019

 

 

5,183,231

 

 

$

2.37

 

 

9.35

 

 

$

 

Options exercisable, June 30, 2019

 

 

1,588,576

 

 

$

3.43

 

 

 

6.37

 

 

$

17,133

 

Summary of Recognized Compensation Cost Related to Employee and Non-employee Stock-Based Compensation Activity

The Company recognized the following compensation cost related to employee and non-employee stock-based compensation activity:

 

 

 

Three Months Ended June 30,

 

 

Six Months Ended June 30,

 

 

 

2019

 

 

2018

 

 

2019

 

 

2018

 

Research and development

 

$

73,463

 

 

$

114,949

 

 

$

232,794

 

 

$

174,013

 

General and administrative

 

 

531,198

 

 

 

762,808

 

 

 

993,552

 

 

 

1,783,465

 

Total

 

$

604,661

 

 

$

877,757

 

 

$

1,226,346

 

 

$

1,957,478

 

Stock Options Valuation Assumptions The calculation was based on the following assumptions.

 

 

 

Three Months Ended

 

 

Six Months Ended

 

 

 

June 30, 2019

 

 

June 30, 2019

 

Expected term (years)

 

5.82

 

 

5.77

 

Risk-free interest rate

 

2.21%

 

 

2.32%

 

Expected volatility

 

65.97%

 

 

65.83%

 

Expected dividend yield

 

0.00%

 

 

0.00%