Material Agreement (Form 8-K)

Pharmakon Loan Agreement Amendment

On January 5, 2026, Geron Corporation ("we" or the "Company") entered into that certain first amendment to loan agreement (the "First Amendment Agreement") with BioPharma Credit Investments V (Master) LP and BPCR Limited Partnership (each, a "Lender"), which are investment funds managed by Pharmakon Advisors, LP, and BioPharma Credit PLC, as collateral agent (the "Agent"), which amends the terms of that certain Loan Agreement, dated as of November 1, 2024 (the "Loan Agreement", and as amended by the First Amendment Agreement, the "Amended Loan Agreement), by and among the Company, the Lenders and the Agent. The Amended Loan Agreement provides for a 5-yearsenior secured term loan facility of up to $250.0 million, divided into three committed tranches: (i) a Tranche A Loan in an aggregate principal amount of $125.0 million (the "Tranche A Loan") which was funded on November 1, 2024 (the "Tranche A Closing Date"); (ii) a Tranche B Loan in an aggregate principal amount of $75.0 million (the "Tranche B Loan") which is available, subject to certain limited conditions, at the Company's option; and (iii) a Tranche C Loan in an aggregate principal amount of $50.0 million (the "Tranche C Loan", and together with the Tranche A Loan and the Tranche B Loan, collectively, the "Term Loans") which is available to the Company upon reaching a specified trailing twelve-month RYTELO^™ revenue milestone. The First Amendment Agreement extended the outside date for requesting the Tranche B Loan and the Tranche C Loan, once available, from December 31, 2025 to July 30, 2026.

We may elect to prepay the Term Loans in part or in whole prior to the Maturity Date with such prepayments being subject to a prepayment premium equal to the principal amount so prepaid multiplied by 3% if made prior to the 3rd anniversary of the funding date of the applicable Term Loan, 2% if made on or after the 3rd anniversary of the funding date of the applicable Term Loan but prior to the 4th anniversary of the funding date of the applicable Term Loan, and 1% if made on or after the 4th anniversary of the funding date of the applicable Term Loan but prior to the Maturity Date. In addition to the prepayment premium, prepayments of any Term Loan prior to a specified date (the "Makewhole Date") are subject to a makewhole amount equal to the sum of all interest that would have accrued from the date of such payment through such Makewhole Date. The First Amendment Agreement extended the Makewhole Date from November 1, 2026 to May 1, 2027.

Except as described above, the terms of the Loan Agreement were unchanged. The foregoing description of the First Amendment Agreement does not purport to be complete and is qualified in its entirety by reference to the complete text of the First Amendment Agreement, a copy of which we expect to file with the U.S. Securities and Exchange Commission as an exhibit to our annual report on Form 10-Kfor the fiscal year ended on December 31, 2025.