Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2018

The following table summarizes stock option activity under the 2014 Plan and the 2016 Plan (collectively, the “Plans”) for the three months ended March 31, 2018 (in thousands, except per share data):


		Weighted		Weighted Average
		Average		Remaining	Aggregate
	Number of	Exercise		Contractual	Intrinsic
	Shares	Price		Life (Years)	Value (a)
Outstanding at December 31, 2017	3,167	$	41.30	8.35	$	219,656
Granted	672	$	124.57
Exercised	(97)	$	26.49
Cancelled or forfeited	(62)	$	42.95
Outstanding at March 31, 2018	3,680	$	56.88	8.45	$	249,205
Exercisable at March 31, 2018	1,240	$	22.52	7.55	$	125,304
Exercisable and expected to vest at March 31, 2018	3,680	$	56.88	8.45	$	249,205

(a) 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, 2018 and December 31, 2017. The intrinsic value of the outstanding stock options as of March 31, 2018 at the purchase price of $218.00 per share in the Offer is equal to $592.9 million (see Note 11).

Summary of stock-based compensation expense by classification in the Statement of Operations and Comprehensive Loss

The Company has recorded total stock-based compensation expense related to the issuance of stock option awards under the Plans in the condensed consolidated statements of operations and comprehensive loss as follows (in thousands):


	Three Months Ended
	March 31,
	2018		2017
Research and development	$	6,995	$	1,978
General and administrative		5,274		2,765
	$	12,269	$	4,743

Summary of weighted-average assumptions used in determining fair value of stock options


	Three Months Ended
	March 31,		March 31,
	2018		2017
Expected volatility	77.68	%	86.88	%
Risk-free interest rate	2.53	%	1.94	%
Expected term (in years)	6.08		6.08
Expected dividend yield	0.00	%	0.00	%

Summary of service-based restricted stock units activity

A summary of the status of the Company's RSUs at March 31, 2018 and of changes in RSUs outstanding under the 2016 Plan for the three months ended March 31, 2018 is as follows (in thousands, except per share data):


		Weighted
		Average
		Grant Date
	Number	Fair Value
	of Shares	Per Share
Outstanding at December 31, 2017	27	$	38.79
Granted	139		129.85
Vested	(10)	$	40.24
Forfeited and cancelled	(0)	$	34.90
Outstanding at March 31, 2018	156	$	119.79

Service Based RSUs

Summary of stock-based compensation expense by classification in the Statement of Operations and Comprehensive Loss

The Company has recorded total stock-based compensation expense related to the issuance of service-based RSUs under the Plans in the condensed consolidated statements of operations and comprehensive loss as follows (in thousands):


	Three Months Ended
	March 31,
	2018		2017
Research and development	$	399	$	302
General and administrative		320		39
	$	719	$	341

AveXis, Inc. 10-Q