7. Promissory Note Receivable

On June 19, 2023, the Company issued a promissory note (the “Note”) with Safi Biotherapeutics, Inc. (“Safi”) in the principal amount of $1,500,000, which was issued in exchange for the convertible promissory note (the “Convertible Note”) issued by the Company to Safi on October 1, 2020. The Note has a maturity date of two (2) years from the date of issuance and can be extended by the mutual consent of the Company and Safi for two (2) additional one (1) year terms upon the payment of all accrued interest accrued through the date of such extension. In addition, the outstanding balance under the Note, or portions thereof, is due within a specified number of days after the receipt by Safi in a closing of specified financing milestones as more detailed in the Note. The Note will bear interest at the rate of 5% per annum and

will increase to 7% for the first one (1) year extension and 9% for the second one (1) year extension. Upon the issuance of the Note, the Convertible Note, which bore interest at the rate of 5% per annum and had a maturity date of October 1, 2023, was voided.

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On August 29, 2024, the Company received a payment from Safi of approximately $713,000 for all interest owed and approximately $419,000 for a partial payment on the outstanding principal on the Note.

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On June 17, 2025, the Company and Safi agreed to extend the maturity date of the Note to June 19, 2026.  Safi paid the Company approximately $45,000 for all accrued interest through the date of the extension in accordance with the terms of the Note. The maturity date of the Note may be further extended through June 19, 2027, and as a result has been classified as a non-current asset.

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For the fiscal years ended June 30, 2025 and 2024, interest income amounted to approximately $62,000 and $88,000, respectively. At June 30, 2025, the Note balance and accrued interest, which have been classified as long term, totaled approximately $1,098,000. At June 30, 2024, $713,000 of the Note balance was reported in current assets with the remaining $1,081,000 reported in noncurrent assets.