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Stock-Based Compensation (Tables)
3 Months Ended
Mar. 31, 2021
Stock-Based Compensation  
Summary of stock option activity

 

 

 

 

 

 

 

 

 

 

 

 

 

Options Outstanding and Exercisable

 

 

 

 

 

 

 

Weighted

 

 

 

 

 

 

 

Weighted

 

Average

 

Aggregate

 

 

 

 

Average

 

Remaining

 

Intrinsic

 

 

Number of

 

Exercise

 

Contractual

 

Value(1)

 

    

Shares

    

Price

    

Life (Years)

    

(in thousands)

Outstanding as of December 31, 2020

 

3,112,376

 

$

16.95

 

8.2

 

$

10,810

Granted

 

1,313,150

 

$

12.49

 

 

 

 

 

Exercised

 

(35,615)

 

$

1.78

 

 

 

 

 

Forfeited

 

(49,776)

 

$

29.26

 

 

 

 

 

Outstanding as of March 31, 2021

 

4,340,135

 

$

15.59

 

8.6

 

$

8,779

Vested and expected to vest as of March 31, 2021

 

4,340,135

 

$

15.59

 

8.6

 

$

8,779

Exercisable as of March 31, 2021

 

1,521,940

 

$

10.77

 

8.4

 

$

6,689


The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying options and the estimated fair value of the common stock for the options that were in the money at March 31, 2021 and December 31, 2020.

Summary of stock based compensation expense recorded

 

 

 

 

 

 

 

 

 

 

 

 

Three Months Ended

 

 

 

March 31, 

 

(in thousands)

    

2021

    

2020

 

Research and development

 

$

958

 

$

452

 

General and administrative

 

 

1,550

 

 

556

 

Total stock-based compensation expense

 

$

2,508

 

$

1,008

 

 

Summary of assumptions used in the Black Scholes option pricing model for stock options granted

 

 

 

 

 

 

 

 

Three Months Ended

 

 

 

March 31, 

 

 

    

2021

    

2020

 

Expected term

 

6.1

years 

6.1

years 

Expected volatility

 

79.7

%

69.7

%

Risk free interest rate

 

0.8 - 1.4

%

0.6 - 1.0

%

Expected dividend yield

 

 —

%

 —

%