Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2019

Share-based Payment Arrangement [Abstract]

Schedule of stock based compensation expense

The Company recorded stock-based compensation expense in the following expense categories of its accompanying consolidated statements of operations and comprehensive loss for the years ended December 31, 2019 and 2018 (amounts in thousands):

	Year Ended December 31,
	2019		2018
Research and development	$	1,299	$	606
General and administrative	3,018		821
Total	$	4,317	$	1,427

Summary of the activity related to stock option grants to employees and nonemployees

The following table summarizes the activity related to stock option grants to employees and nonemployees for the years ended December 31, 2019 and 2018:

	Shares	Weighted-average exercise price share		Weighted-average remaining contractual life (years)
Outstanding at January 1, 2018	703,479	$	4.91	7.8
Options assumed from OvaScience Merger	423,316	78.70
Granted	776,140	15.82
Cancelled	(72,049)	16.40
Forfeited	(66,599)	8.54
Outstanding at December 31, 2018	1,764,287	26.81		8.0
Granted	1,225,901	9.73
Exercised	(97,225)	3.71
Forfeited	(394,357)	40.42
Outstanding at December 31, 2019	2,498,606	$	17.18	7.7
Vested and exercisable at December 31, 2019	984,264	$	26.42	5.6
Vested and expected to vest at December 31, 2019	2,498,606	$	17.18	7.7

Summary of grant date fair value assumptions

The grant date fair value of each option grant was estimated throughout the year using the Black-Scholes option-pricing model using the following assumptions for the Plan:

	Year Ended, December 31,			Year Ended, December 31,
	2019			2018
Expected term (in years)	6.02			6.08
Expected volatility	80		%	66		%
Risk-free interest rate	2.22		%	2.77		%
Expected dividend yield	0		%	0		%
Fair market value of common stock	$	9.73		$	15.82