Note 8 – Notes Payable

As of March 31, 2026 and December 31, 2025, notes payable and convertible notes payable consisted of the following:

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Avenue Loan

On June 17, 2025, the Company entered into the Fourth Amendment of the Loan and Security Agreement with Avenue Venture Opportunities Fund, L.P., and Avenue Venture Opportunities Fund, L.P. II (the “Avenue Loan”) which, among other things, extended the maturity date of the loans to July 1, 2028; provided for an interest - only period from July 1, 2025 until January 31, 2027; and reduced the interest rate from 12.0% to 8.0% (payable half in cash and half in kind). For the three months ended March 31, 2026, the effective interest rate was 8.16%.

As of March 31, 2026, the Avenue Loan matures as follows:

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During the three months ended March 31, 2026 and 2025, the Company recorded interest expense related to the Avenue Loan of $222,804 (which includes $55,461 of amortization of debt discount) and $581,499 (which includes $277,972 of amortization of debt discount), respectively. During the three months ended March 31, 2026, interest expense in the amount of $83,672 was added to the principal balance outstanding.

FIRST Insurance Funding Loan

On February 24, 2026, the Company issued a note payable in the amount of $598,055 for the purchase of a directors and officers’ liability insurance policy (the “2026 D&O Loan”). The note accrues interest at a rate of 6.15% per year and matures on December 24, 2026. The 2026 D&O Loan is payable in ten monthly payments of $61,504 consisting of principal and interest. Interest expense for the three months ended March 31, 2026 was $3,065.