The Company has entered into various research, development, license and supply agreements with Serum Institute and Pharmsynthez, each a related party whose relationship, ownership, and nature of transactions is disclosed within other sections of these footnotes. Please refer to Note 4, Significant Strategic Collaborations, and Note 6, Indefinite-Lived Intangible Assets and Other Long-Term Assets, for details on arrangements with collaboration partners that are also related parties.

During the fourth quarter of 2019, the Company entered into a loan agreement with Pharmsynthez (the “Pharmsynthez Loan”), pursuant to which the Company advanced Pharmsynthez an aggregate principal amount of up to $500,000 to be used for the development of a specific product under the Company’s Co-Development Agreement with Pharmsynthez. The Pharmsynthez Loan had a term of 15-months and accrued interest at a rate of 10% per annum. The Pharmsynthez Loan is guaranteed by all of the operating subsidiaries of Pharmsynthez, including SynBio and AS Kevelt, and is secured by all of the common and preferred stock of the Company owned by Pharmsynthez and SynBio, as more fully described in Note 4 Significant Strategic Collaborations. The Company recognized approximately $48,000 and $51,000 of interest income related to this loan during the twelve-months ended December 31, 2021 and 2020, respectively.

Effective January 23, 2021, the Company entered into a First Amendment to Loan Agreement and Other Loan Documents with Pharmsynthez, Kevelt and SynBio (the “Pharmsynthez Loan Extension”) to modify the repayment terms and maturity of the Pharmsynthez Loan to January 2022. The terms of the Pharmsynthez Loan Extension called for two (2) equal monthly principal payments of $25,000 in each of January 23, 2021 and February 28, 2021 and the payment of all outstanding accrued interest in six (6) equal monthly installments from January 31, 2021 through June 30, 2021. In addition, the Pharmsynthez Loan Extension required monthly interest payments and the repayment of the remaining principal amount in six (6) equal monthly installments from August 2021 through January 2022.

Effective August 31, 2021, the Company entered into a Second Amendment to Loan Agreement and Other Loan Documents with Pharmsynthez, Kevelt and SynBio (the “Second Pharmsynthez Loan Extension”) to modify the repayment terms and maturity of the Pharmsynthez Loan to July 2022. The terms of the Second Pharmsynthez Loan Extension called for an upfront fee of $12,500 and two (2) equal monthly principal payments of $25,000 on September 30, 2021 and October 31, 2021. In addition, the Second Pharmsynthez Loan Extension requires monthly interest payments and the repayment of the remaining principal amount in six (6) equal monthly installments from February 2022 through July 2022. All other terms of the Pharmsynthez Loan, as amended, remain in effect. All required payments under the Second Pharmsynthez Loan Extension have been made through January 31, 2022. In February 2022, the Company received a request from Pharmsynthez to further extend the principal repayments until September 2022. The Company agreed to extend the maturity date, although final terms of such extension are under negotiation. All other terms of the Pharmsynthez Loan, as amended, are expected to remain in effect including the continued payment of interest on a monthly basis. As a result of this request and the current economic uncertainty due to the conflict between Russia and Ukraine and associated sanctions imposed by the U.S. and other countries in response, the Company has classified the loan receivable as long-term as of December 31, 2021. The Company assessed the collectability of the loan and determined that the collateral held by the Company, consisting of all of the common and preferred stock of the Company owned by Pharmsynthez and SynBio, was adequate to support the outstanding principal balance. As of December 31, 2021, approximately $0.4 million was included in other assets on the consolidated balance sheet. As of December 31, 2020, approximately $0.5 million was classified within prepaid expenses and other assets and approximately $0.1 million was classified within other assets on the consolidated balance sheet.

The Company performed a review of events subsequent to the balance sheet date through the date the financial statements were issued and determined that, other than the further extension of the Pharmsynthez Loan discussed in Note 14 Related Party Transactions, there were no such events requiring recognition or disclosure in the financial statements.