Quarterly report pursuant to Section 13 or 15(d)

Stock Plans (Tables)

v3.19.1
Stock Plans (Tables)
3 Months Ended
Mar. 31, 2019
Share-based Compensation [Abstract]  
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]
The following table summarizes the stock-based compensation expense recorded for awards under our stock option plans (in thousands):
 
 
 
Three Months Ended

March 31,
 
(in thousands)
 
2019
 
 
2018
 
Research and development
 
$
77
 
 
$
163
 
Selling, general and administrative
 
 
59
 
 
 
269
 
Total stock-based compensation expense
 
$
136
 
 
$
432
 
Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]
We use the Black-Scholes-Merton option-pricing model with the following assumptions to estimate the fair value of our stock options:
 
 
 
Three Months Ended

March 31,
 
 
 
2019
 
 
2018
 
Weighted-average risk-free interest rate
 
 
2.58
%
 
 
2.75
%
Expected dividend payments
 
 
 
 
 
 
Expected holding period (years)
1
 
 
6.3
 
 
 
6.4
 
Weighted-average volatility factor
2
 
 
0.91
 
 
 
0.89
 
Estimated forfeiture rates for options granted
3
 
 
25
%
 
 
26
%
   
(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.
Share-based Payment Arrangement, Option, Activity [Table Text Block]
The following table summarizes option activity:
 
 
 
Options 
(in
thousands)
 
 
Weighted

Average

Exercise

Price per
share
 
 
Weighted

Average

Remaining

Option

Term (in
years)
 
 
Aggregate

Intrinsic

Value 
(in
thousands)
 
Outstanding at January 1, 2019
 
 
665
 
 
$
17.94
 
 
 
6.44
 
 
$
4
 
Granted
 
 
5
 
 
 
1.60
 
 
 
 
 
 
 
 
 
Forfeited
 
 
(8
)
 
 
31.17
 
 
 
 
 
 
 
 
 
Outstanding at March 31, 2019
 
 
662
 
 
$
11.92
 
 
 
6.24
 
 
$
67
 
Exercisable at March 31, 2019
 
 
576
 
 
$
13.48
 
 
 
5.75
 
 
$
31