|
The
following table summarizes option activity:
| Schedule of our 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 December 31, 2022 |
|
|
927 |
|
|
$ |
7.97 |
|
|
|
8.34 |
|
|
$ |
- |
|
| Forfeited or expired |
|
|
(16 |
) |
|
|
119.39 |
|
|
|
- |
|
|
|
- |
|
| Outstanding at March 31, 2023 |
|
|
911 |
|
|
|
6.06 |
|
|
|
8.12 |
|
|
|
|
|
| Exercisable at March 31, 2023 |
|
|
911 |
|
|
|
6.06 |
|
|
|
8.12 |
|
|
|
- |
|
During
August and September 2022, our Board granted 125,000 options to purchase common stock at $1.52 per share and 900,000 options to
purchase common stock at $1.31 per share which are subject to shareholder approval of an amendment to increase the number of shares reserved
for issuance under our 2015 Plan. The options vest monthly over a 12-month period from the grant dates. As the shares underlying these
options have not been approved by our stockholders, they have been excluded from the table above as of March 31, 2023.
The
following table summarizes the stock-based compensation expense recorded for awards under our stock option plans (in thousands):
| Schedule of the stock-based compensation expense |
|
|
|
|
|
|
|
|
| |
|
Three Months Ended |
|
|
|
March 31, |
|
| (in thousands) |
|
2023 |
|
|
2022 |
|
| Research and development |
|
$ |
28 |
|
|
$ |
123 |
|
| Selling, general and administrative |
|
|
262 |
|
|
|
103 |
|
| Total stock-based compensation |
|
$ |
290 |
|
|
$ |
226 |
|
We
use the Black-Scholes-Merton option-pricing model with the following assumptions to estimate the fair value of our stock options:
| Schedule of assumptions to estimate the fair value of options |
|
|
|
|
|
|
|
|
| |
|
Three Months Ended |
|
| |
|
March 31, |
|
| |
|
2023 |
|
|
2022 |
|
| Weighted-average risk-free interest rate |
|
|
- |
% |
|
|
1.47 |
% |
| Expected dividend payments |
|
|
- |
|
|
|
- |
|
| Expected holding period (years) 1 |
|
|
- |
|
|
|
5.4 |
|
| Weighted-average volatility factor 2 |
|
|
- |
|
|
|
113.2 |
|
| Estimated forfeiture rates for options granted 3 |
|
|
- |
% |
|
|
5.14 |
% |
| (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. |
As
of March 31, 2023, there was approximately $0.6 million of total unrecognized compensation expense related to non-vested stock options
subject to shareholder approval. This expense is expected to be recognized over a weighted-average period of approximately 0.5 year.
|