Annual report pursuant to Section 13 and 15(d)

Stock-Based Compensation (Tables)

v3.20.4
Stock-Based Compensation (Tables)
12 Months Ended
Dec. 31, 2020
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]  
Summary of Activity under Stock Option Plans and Related Information

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

 

 

 

Number of

Options

Outstanding

 

 

Weighted

Average

Exercise Price

 

 

Weighted Average

Remaining

Contractual Term

(Years)

 

 

Aggregate

Intrinsic Value

 

Outstanding at December 31, 2019

 

 

3,107,066

 

 

$

7.19

 

 

 

8.2

 

 

$

3,151

 

Options granted

 

 

1,503,876

 

 

$

3.87

 

 

 

 

 

 

 

 

 

Options exercised

 

 

(56,653

)

 

$

1.95

 

 

 

 

 

 

$

185

 

Options cancelled/forfeited

 

 

(65,167

)

 

$

7.84

 

 

 

 

 

 

 

 

 

Outstanding at December 31, 2020

 

 

4,489,122

 

 

$

6.14

 

 

 

7.8

 

 

$

7,134

 

Vested and exercisable at December 31, 2020

 

 

2,358,197

 

 

$

5.62

 

 

 

7.0

 

 

$

4,627

 

 

Stock-Based Compensation Expense Recognized

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

 

 

 

Year Ended December 31,

 

 

 

2020

 

 

2019

 

 

2018

 

Research and development

 

$

2,102

 

 

$

1,777

 

 

$

842

 

General and administrative

 

 

2,841

 

 

 

2,230

 

 

 

1,151

 

Total stock-based compensation expense

 

$

4,943

 

 

$

4,007

 

 

$

1,993

 

 

Fair Value of Employee Stock Options Granted and ESPP Rights to Purchase Common Stock Calculated Using Black Scholes Option Pricing Model with Weighted Average Assumptions

The fair value of the employee stock options granted and the ESPP rights to purchase common stock of the Company is calculated using the Black-Scholes option-pricing model with the following weighted-average assumptions:

 

 

 

Options

 

 

ESPP Rights

 

 

 

Year Ended December 31,

 

 

Year Ended December 31,

 

 

 

2020

 

 

2019

 

 

2018

 

 

2020

 

 

2019

 

 

2018

 

Expected term (years)

 

5.5 - 6.0

 

 

5.8 - 5.9

 

 

5.5 - 6.1

 

 

 

0.5

 

 

 

0.5

 

 

 

0.5

 

Expected volatility

 

83.8 - 91.9%

 

 

78.7 - 83.7%

 

 

82.0 - 83.2%

 

 

101.7 - 114.3%

 

 

73.7 - 109.9%

 

 

 

74.3

%

Risk-free interest rate

 

0.4 - 1.6%

 

 

1.5 - 2.6%

 

 

2.6 - 3.1%

 

 

0.1 - 0.2%

 

 

1.6 - 2.4%

 

 

 

2.5

%

Expected dividend yield