Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation (Tables)

v3.20.2
Stock-Based Compensation (Tables)
 9 Months Ended
Sep. 30, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]  
Stock-Based Compensation Expense

Stock-based compensation expense, which consists of the compensation cost for employee stock options and the value of options issued to non-employees for services rendered, was allocated to research and development and general and administrative in the consolidated statements of operations as follows (in thousands):  

 

 

Three Months Ended

September 30,

 

 

Nine Months Ended

September 30,

 

 

 

2020

 

 

2019

 

 

2020

 

 

2019

 

Research and development

 

$

1,774

 

 

$

655

 

 

$

4,636

 

 

$

1,690

 

General and administrative

 

 

1,511

 

 

 

872

 

 

 

3,891

 

 

 

2,640

 

Total stock-based compensation

 

$

3,285

 

 

$

1,527

 

 

$

8,527

 

 

$

4,330

 

 
Weighted-Average Fair Value Valuation Assumptions

The fair value of employee stock options was estimated using the following weighted-average assumptions:

 

 

 

Three Months Ended

September 30,

 

 

Nine Months Ended

September 30,

 

 

 

2020

 

 

2019

 

 

2020

 

 

2019

 

Employee Stock Options:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Risk-free interest rate

 

 

0.49

%

 

 

1.87

%

 

 

1.47

%

 

 

2.47

%

Expected term (in years)

 

 

6.08

 

 

 

6.08

 

 

 

6.08

 

 

 

6.08

 

Dividend yield

 

 

—

 

 

 

—

 

 

 

—

 

 

 

—

 

Volatility

 

 

112.02

%

 

 

107.21

%

 

 

110.81

%

 

 

108.67

%

Weighted-average fair value of stock options granted

 

$

9.29

 

 

$

4.96

 

 

$

11.89

 

 

$

4.36

 

 
Stock Option Activity Under Equity Incentive Plan

The following table summarizes stock option activity under the Company’s equity incentive plans:

Options

 

Number of

Shares

 

 

Weighted-

Average

Exercise

Price

 

 

Weighted-

Average

Remaining

Contractual

Term

 

 

Aggregate

Intrinsic

Value (in millions)

 

Outstanding at December 31, 2019

 

 

4,763,062

 

 

$

6.36

 

 

 

8.1

 

 

$

36.6

 

Granted

 

 

2,374,006

 

 

$

14.23

 

 

 

—

 

 

$

—

 

Exercised

 

 

(240,659

)

 

$

3.87

 

 

 

—

 

 

$

—

 

Forfeitures

 

 

(104,436

)

 

$

11.12

 

 

 

—

 

 

$

—

 

Outstanding at September 30, 2020

 

 

6,791,973

 

 

$

9.12

 

 

 

8.2

 

 

$

20.5

 

Exercisable at September 30, 2020

 

 

2,554,485

 

 

$

6.47

 

 

 

7.1

 

 

$

11.9