Common Stock (Tables)
|
12 Months Ended |
Dec. 31, 2021 |
|---|
| Equity [Abstract] |
|
| Summary of Fair Value of Option Awards |
The estimated fair value of stock options granted in the respective periods was determined using the Black-Scholes option pricing model using the following weighted average assumptions:
|
|
|
2021 |
|
|
2020 |
|
|
|
Risk-free interest rates |
|
|
0.66 |
% |
|
|
0.94 |
% |
|
|
Expected dividend yield |
|
|
0 |
% |
|
|
0 |
% |
|
|
Expected life |
|
6.00 years |
|
|
6.00 years |
|
|
|
Expected volatility |
|
|
110.10 |
% |
|
|
108.78 |
% |
|
|
Forfeiture rate |
|
|
0 |
% |
|
|
0 |
% |
|
|
| Summary of Share-Based Compensation Expense |
The results for the periods set forth below included stock-based compensation expense in the following expense categories of the consolidated statements of loss (in thousands):
|
|
|
Year ended |
|
|
|
|
December 31, |
|
|
|
|
2021 |
|
|
2020 |
|
|
Research and development |
|
$ |
685 |
|
|
$ |
403 |
|
|
General and administrative |
|
|
1,502 |
|
|
|
883 |
|
|
Total stock-based compensation |
|
$ |
2,187 |
|
|
$ |
1,286 |
|
|
| Summary of Stock Options Activity |
Stock option transactions and the number of stock options outstanding are summarized below:
|
|
|
Number of |
|
|
Weighted |
|
|
|
|
Optioned |
|
|
Average |
|
|
|
|
Common |
|
|
Exercise |
|
|
|
|
Shares |
|
|
Price |
|
|
Balance, January 1, 2021 |
|
|
227,442 |
|
|
$ |
44.64 |
|
|
Granted |
|
|
294,650 |
|
|
|
12.07 |
|
|
Expired |
|
|
(2 |
) |
|
|
39,204.00 |
|
|
Balance, December 31, 2021 |
|
|
522,090 |
|
|
$ |
26.11 |
|
|
| Summary of Stock Options Outstanding Regarding Number of Common Shares Issuable upon Exercise of Outstanding Options |
(1) Number of common shares issuable upon exercise of outstanding options:
|
|
|
|
|
|
|
|
|
|
|
Weighted- |
|
|
|
|
|
|
|
|
|
|
|
|
Average |
|
|
|
|
|
|
|
|
|
|
|
|
Remaining |
|
|
|
|
|
|
|
|
Weighted- |
|
|
Contractual |
|
|
|
|
|
|
|
|
Average |
|
|
Life |
|
|
Exercise Prices |
|
Number of Options |
|
|
Exercise Price |
|
|
(in years) |
|
|
$7.20 - $9.25 |
|
|
50,500 |
|
|
$ |
7.48 |
|
|
|
9.49 |
|
|
$9.26 - $10.13 |
|
|
11,250 |
|
|
|
9.90 |
|
|
|
9.36 |
|
|
$10.14 - $10.78 |
|
|
98,000 |
|
|
|
10.36 |
|
|
|
8.88 |
|
|
$10.79 - $11.65 |
|
|
74,880 |
|
|
|
11.20 |
|
|
|
8.08 |
|
|
$11.66 - $12.60 |
|
|
5,650 |
|
|
|
12.10 |
|
|
|
9.20 |
|
|
$12.61 - $20.74 |
|
|
232,750 |
|
|
|
13.09 |
|
|
|
9.07 |
|
|
$20.75 - $39.80 |
|
|
14,766 |
|
|
|
28.40 |
|
|
|
7.08 |
|
|
$39.81 - $59.30 |
|
|
18,747 |
|
|
|
51.20 |
|
|
|
6.72 |
|
|
$59.31 - $67.50 |
|
|
8,087 |
|
|
|
67.40 |
|
|
|
6.57 |
|
|
$67.51 - $28,952.00 |
|
|
7,460 |
|
|
|
837.69 |
|
|
|
6.00 |
|
|
|
|
|
522,090 |
|
|
$ |
26.11 |
|
|
|
8.72 |
|
|
| Summary of Stock Options Outstanding Regarding Number of Common Shares Issuable upon Exercise of Vested Options |
(2) Number common shares issuable upon exercise of vested options:
|
|
|
|
|
|
|
|
|
|
|
Weighted- |
|
|
|
|
|
|
|
|
|
|
|
|
Average |
|
|
|
|
|
|
|
|
|
|
|
|
Remaining |
|
|
|
|
|
|
|
|
Weighted- |
|
|
Contractual |
|
|
|
|
|
|
|
|
Average |
|
|
Life |
|
|
Exercise Prices |
|
Number of Options |
|
|
Exercise Price |
|
|
(in years) |
|
|
$7.20 - $9.25 |
|
|
5,500 |
|
|
$ |
8.60 |
|
|
|
8.36 |
|
|
$9.26 - $10.13 |
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
$10.14 - $10.78 |
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
$10.79 - $11.65 |
|
|
35,937 |
|
|
|
11.20 |
|
|
|
8.08 |
|
|
$11.66 - $12.60 |
|
|
1,413 |
|
|
|
12.10 |
|
|
|
9.20 |
|
|
$12.61 - $20.74 |
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
$20.75 - $39.80 |
|
|
11,862 |
|
|
|
28.40 |
|
|
|
7.08 |
|
|
$39.81 - $59.30 |
|
|
15,839 |
|
|
|
51.20 |
|
|
|
6.72 |
|
|
$59.31 - $67.50 |
|
|
6,939 |
|
|
|
67.40 |
|
|
|
6.57 |
|
|
$67.51 - $28,952.00 |
|
|
7,332 |
|
|
|
851.13 |
|
|
|
5.98 |
|
|
|
|
|
84,822 |
|
|
$ |
98.12 |
|
|
|
7.42 |
|
|
| Summary of Restricted Stock Unit Award Activity |
The following table summarizes our restricted stock unit award activity during the year ended December 31, 2021:
|
|
|
|
|
|
|
Weighted |
|
|
|
|
Number |
|
|
Average |
|
|
|
|
of |
|
|
Grant Date |
|
|
|
|
Shares |
|
|
Fair Value |
|
|
Balance, January 1, 2021 |
|
|
231 |
|
|
$ |
580.00 |
|
|
Granted |
|
|
53,250 |
|
|
|
13.09 |
|
|
Released |
|
|
(231 |
) |
|
|
580.00 |
|
|
Balance, December 31, 2021 |
|
|
53,250 |
|
|
$ |
13.09 |
|
|
| Summary of Outstanding Warrants |
The following is a summary of outstanding warrants to purchase common stock at December 31, 2021:
|
|
|
Total |
|
|
|
|
|
|
|
|
|
|
Outstanding |
|
|
Exercise |
|
|
|
|
|
|
and |
|
|
price per |
|
|
|
|
|
|
Exercisable |
|
|
Share |
|
|
Expiration Date |
|
(1) Warrants issued in September 2017 financing |
|
|
411 |
|
|
$ |
699.2000 |
|
|
March 2023 |
|
(2) Warrants issued in June 2018 financing |
|
|
114,100 |
|
|
$ |
80.0000 |
|
|
June 2023 |
|
(3) Warrants issued in October 2018 financing |
|
|
31,215 |
|
|
$ |
62.8900 |
|
|
October 2023 |
|
(4) Warrants issued in May 2019 financing |
|
|
60,000 |
|
|
$ |
90.0000 |
|
|
May 2025 |
|
(5) Warrants issued in December 2019 financing |
|
|
612,967 |
|
|
$ |
6.6000 |
|
|
December 2024 |
|
(6) Warrants issued in April 2020 financing |
|
|
182,461 |
|
|
$ |
7.2400 |
|
|
April 2025 |
|
(7) Warrants issued in April 2020 financing |
|
|
24,375 |
|
|
$ |
7.3200 |
|
|
April 2025 |
|
(8) Warrants issued in April 2020 financing |
|
|
25,270 |
|
|
$ |
7.5900 |
|
|
April 2025 |
|
(9) Pre-Funded Warrants issued in August 2020 financing |
|
|
142,857 |
|
|
$ |
0.0010 |
|
|
* |
|
(10) Warrants issued in December 2020 financing |
|
|
50,000 |
|
|
$ |
8.7500 |
|
|
December 2025 |
|
|
|
|
|
|
|
|
|
|
|
|
|
| Computation of Basic and Diluted Net Loss Attributable to Common Shareholders Per Share |
The following table presents the computation of basic and diluted net loss attributable to common stockholders per share (in thousands, except per share and share amounts):
|
|
|
Years ended December 31, |
|
|
|
|
2021 |
|
|
2020 |
|
|
2019 |
|
|
Numerator |
|
|
|
|
|
|
|
|
|
|
|
|
|
Net loss |
|
$ |
(33,152 |
) |
|
$ |
(14,730 |
) |
|
$ |
(16,395 |
) |
|
Denominator |
|
|
|
|
|
|
|
|
|
|
|
|
|
Weighted average number of common shares outstanding |
|
|
8,119,836 |
|
|
|
2,718,909 |
|
|
|
412,320 |
|
|
Basic and diluted net loss per common share |
|
$ |
(4.08 |
) |
|
$ |
(5.42 |
) |
|
$ |
(39.76 |
) |
|