Share-based Compensation (Tables)

12 Months Ended

Jun. 30, 2020

Share-Based Compensation Expense for Stock Awards

Total share-based compensation expense for all stock awards consists of the following, in thousands:

	Years Ended June 30,
	2020		2019		2018
Research and development	$	2,777	$	2,239	$	1,176
General and administrative		4,024		4,323		2,041
Total share-based compensation	$	6,801	$	6,562	$	3,217

Summary of Stock Option Activity and Related Data

A summary of our stock option activity and related data follows:

	Number of Options			Weighted-Average Exercise Price		Weighted-Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value
Outstanding at June 30, 2019		8,356,961		$	3.20
Granted		3,733,333		$	2.50
Exercised		(153,679	)	$	1.77
Forfeited / Cancelled		(125,749	)	$	2.45
Expired		(557,890	)	$	6.89
Outstanding at June 30, 2020		11,252,976		$	2.81		7.8	$	15,290,655
Vested and exercisable at June 30, 2020		5,475,069		$	2.66		7.0	$	8,330,387

Non-vested Stock Option Activity

A summary of our non-vested stock option activity:

	Number of Options			Weighted-Average Grant Date Fair Value
Nonvested at June 30, 2019		4,376,928		$	3.51
Granted		3,733,333		$	2.50
Forfeited		(76,563	)	$	2.86
Vested		(2,255,791	)	$	3.26
Nonvested at June 30, 2020		5,777,907		$	2.96

Fair Value of Stock Options Weighted-Average Assumptions Used

We use a Black-Scholes valuation model to estimate the grant date fair value of stock options. To calculate these fair values, the following weighted-average assumptions were used:

	Years Ended June 30,
	2020			2019			2018
Risk-free interest rate		1.7	%		2.7	%		2.3	%
Expected life (years)		6.0			6.0			6.0
Expected volatility		74.1	%		82.5	%		93.7	%
Dividend yield		0.0	%		0.0	%		0.0	%
Weighted-average grant date fair value	$	1.64		$	2.78		$	2.40