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COMMON STOCK, STOCK-BASED COMPENSATION AND WARRANTS (Tables) | 9 Months Ended
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Sep. 30, 2025
COMMON STOCK, STOCK-BASED COMPENSATION AND WARRANTS |
Schedule of stock were valued on the date of issuance using the Monte Carlo pricing model with the following assumptions | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | Series A Right Warrant |  | Series B Right Warrant | ​
Common Stock Price as of Issuance Date | ​ | $ | 0.94 | ​ | $ | 0.94 | ​
Risk-Free Rate | ​ | ​ | 4.31 | % |  | 4.27 | %
Dividend Rate | ​ | ​ | 0.00 | % |  | 0.00 | %
Volatility | ​ | ​ | 88.90 | % |  | 97.19 | %
Minimum Exercise Price | ​ | $ | 1.00 | ​ | $ | 2.00 | ​
Maximum Exercise Price | ​ | $ | 2.00 | ​ | $ | 4.00 | ​
Formula for Exercise Price | ​ | ​ | 90% of the 5-day volume weighted average stock price as of the exercise date rounded down to the nearest cent, not to fall outside the range of the maximum and minimum exercise prices. | ​
Schedule of stock-based compensation expense | ​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | Three Months Ended September 30,
Stock-based compensation expense by category | ​ | 2025 | ​ | 2024
​ | ​ | (amounts, in thousands)
Cost of goods sold | ​ | $ | 29 | ​ | $ | 48
Research and development, net of grant income | ​ |  | 83 | ​ |  | —
Selling, general and administrative | ​ |  | 376 | ​ | ​ | 843
Total stock-based compensation expense | ​ | $ | 488 | ​ | $ | 891
​
​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | Nine Months Ended September 30,
Stock-based compensation expense by category | ​ | 2025 |  | 2024
​ | ​ | (amounts, in thousands)
Cost of goods sold | ​ | $ | 114 | ​ | $ | 48
Research and development, net of grant income | ​ | ​ | 330 | ​ | ​ | —
Selling, general and administrative | ​ |  | 1,435 | ​ |  | 2,792
Total stock-based compensation expense | ​ | $ | 1,879 | ​ | $ | 2,840
​
Schedule of stock options activity | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | Weighted
​ | ​ | ​ | ​ | Weighted | ​ | Average
​ | ​ | ​ | ​ | Average | ​ | Remaining
​ | ​ | ​ | ​ | Exercise Price | ​ | Contractual
​ |  | Shares |  | per Share |  | Life (Years)
Outstanding, December 31, 2024 |  | 12,341,907 | ​ | $ | 3.55 | ​ | 6.81
Granted |  | 787,000 | ​ | ​ | 1.00 |  | —
Exercised | ​ | (11,650) | ​ | ​ | 0.96 | ​ | —
Forfeited |  | (110,985) | ​ | ​ | 2.09 |  | —
Expired |  | (255,552) | ​ | ​ | 6.15 |  | —
Outstanding, September 30, 2025 |  | 12,750,720 | ​ | $ | 3.36 |  | 6.37
Schedule of fair value of each stock option estimated using the Black-Scholes pricing model | The Company estimated the fair value of stock options granted during the nine months ended September 30, 2025 using a Black-Scholes pricing model, which used the following inputs: ​
​ | ​ | ​ | ​ | ​
Exercise price (per share) | ​ | $ | 0.82 - $1.30 | ​
Expected volatility | ​ |  | 80.7 - 81.7 | %
Expected term* | ​ |  | 6.3 years | ​
Risk-free rate | ​ |  | 3.89% - 4.40 | %
Dividends | ​ |  | 0 | %
​ *The expected term of the options granted is derived using the “simplified method” which computes expected term as the average of the sum of the vesting term plus the contract term. The simplified method is used as the Company’s employee exercise history may not be indicative for estimating future exercises. In addition, the Company recognizes forfeitures as they occur. ​
Schedule of intrinsic value | The intrinsic value is calculated as the difference between the market value of the shares as of September 30, 2025 of $0.93 and the exercise price of the shares. ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Options Outstanding
​ | ​ | Number | ​ | Weighted | ​ | Weighted | ​ | Aggregate
Range of | ​ | Outstanding at | ​ | Average | ​ | Average | ​ | Intrinsic
Exercise | ​ | September 30, | ​ | Exercise | ​ | Remaining | ​ | Value
Price |  | 2025 |  | Price |  | Life (Years) |  | (in thousands)
$0.82 - $13.20 |  | 12,750,720 | ​ | $ | 3.36 | ​ | 6.37 | ​ | $ | 4
​
​ | ​ | ​ | ​ | ​ | ​ | ​
Options Exercisable
Number | ​ | Weighted | ​ | Aggregate
Exercisable at | ​ | Average | ​ | Intrinsic
September 30, | ​ | Exercise | ​ | Value
2025 |  | Price |  | (in thousands)
8,767,055 | ​ | $ | 4.14 | ​ | $ | 2
Schedule of company's non-vested options | ​
​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | Weighted
​ | ​ | ​ | ​ | Average
​ | ​ | ​ | ​ | Exercise
​ |  | Shares |  | Price
Non-vested, December 31, 2024 |  | 6,234,550 | ​ | $ | 1.09
Granted |  | 787,000 | ​ | $ | 1.00
Forfeited |  | (110,985) | ​ | $ | 2.09
Vested |  | (2,926,891) | ​ | $ | 1.55
Non-vested, September 30, 2025 |  | 3,983,674 | ​ | $ | 1.63
Schedule of outstanding balance of restricted stock units | ​
​ | ​ | ​
​ | ​ | Total
​ | ​ | (amounts in thousands, except share data)
Outstanding, December 31, 2024 |  | 2,809,500
Granted |  | 121,500
Vested | ​ | (35,000)
Forfeited |  | (49,000)
Outstanding, September 30, 2025 |  | 2,847,000
Schedule of the restricted stock unit activity | ​
​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | Weighted
​ | ​ | ​ | ​ | Average
​ | ​ | ​ | ​ | Grant Date
​ |  | Shares |  | Fair Value
Non-vested, January 1, 2025 |  | 641,335 | ​ | $ | 1.31
Granted | ​ | 498,800 | ​ | ​ | 1.01
Vested |  | (264,835) | ​ | ​ | 1.81
Unvested shares forfeited | ​ | (65,000) | ​ | ​ | 0.96
Non-vested, September 30, 2025 |  | 810,300 | ​ | $ | 0.99

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