Cabaletta Bio, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Common Stock (Tables)

Common Stock (Tables)

9 Months Ended

Sep. 30, 2020

A summary of stock option activity is presented below:

	Number of Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (years)		Aggregate Intrinsic Value
Outstanding as of January 1, 2020		2,129,632		$	5.12		9.2	$	18,844
Granted		797,572			13.06
Exercised		(21,445	)		6.30				121
Forfeited		(16,714	)		6.30
Outstanding as of September 30, 2020		2,889,045			7.30		8.8		12,622
Options Exercisable at September 30, 2020		784,221			3.58		8.3		5,745

Schedule of Assumptions Used to Estimate Fair Value of Stock Options

The fair value of each award is estimated using Black-Scholes based on the following assumptions:

	Nine months ended September 30,
	2020	2019
Risk-free interest rate	0.28%—1.48%	1.39%—2.59%
Expected term	5.7—6.1 years	0.3—6.1 years
Expected volatility	70%—79%	70%—76%
Expected dividend yield	0%	0%

Summary of Stock-Based Compensation

The Company recognizes stock-based compensation with respect to equity awards under the 2018 and 2019 Plans, the 2019 ESPP and with respect to vesting common stock issued to founders. The Company has recorded stock-based compensation in the accompanying statements of operations as follows:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2020		2019		2020		2019
Research and development	$	539	$	365	$	1,449	$	962
General and administrative		588		204		1,618		519
Total	$	1,127	$	569	$	3,067	$	1,481