Quarterly report pursuant to Section 13 or 15(d)

Stock Plans (Tables)

Stock Plans (Tables)

6 Months Ended

Jun. 30, 2021

Stock Plans

Schedule of option activity

The following table summarizes option activity:


							Weighted
				Weighted			Average
				Average			Remaining		Aggregate
				Exercise			Option		Intrinsic
		Options (in		Price per			Term		Value
		thousands)		share			(in years)		(in thousands)
Outstanding at December 31, 2020		28		$	242.70		6.35		$	—
Granted		670			4.02
Forfeited or expired		(6)			137.74
Outstanding at June 30, 2021		692		$	12.46		9.49		$	—
Exercisable at June 30, 2021		22		$	272.90		5.50		$	—

Schedule of the stock-based compensation expense

The following table summarizes the stock-based compensation expense recorded for awards under our stock option plans (in thousands):


		Three Months Ended						Six Months Ended
(in thousands)		June 30,						June 30,
		2021			2020			2021			2020
Research and development		$	214		$	—		$	334		$	—
Selling, general and administrative			233			79			361			(5)
Total stock-based compensation		$	447		$	79		$	695		$	(5)

Schedule of assumptions to estimate the fair value of options


		Three Months Ended				Six Months Ended
		June 30,				June 30,
		2021		2020		2021		2020
Weighted-average risk-free interest rate		—	%	0.4	%	0.5	%	0.4	%
Expected dividend payments		—		—		—		—
Expected holding period (years)¹		—		5.8		5.5		5.8
Weighted-average volatility factor²		—		1.04		1.14		1.04
Estimated forfeiture rates for options granted ³		—	%	28	%	30	%	28	%

(1)	Expected holding period is based on historical experience of similar awards, giving consideration to the contractual terms of the stock-based awards, vesting schedules and the expectations of future employee behavior.

(2)	Weighted average volatility is based on the historical volatility of our common stock.

(3)	Estimated forfeiture rates are based on historical data.