What Geron Corp told the SEC could break it.

Geron's RYTELO sales flow through a few distributors — three customers were ~45%, 32% and 21% of gross product-related accounts receivable at year-end 2025 — so loss of any would materially disrupt revenue and collections.

“As of December 31, 2025 , three customers individually accounted for approximately 45 % , 32 % and 21 % of our gross accounts rec eivable associated with our product revenue”

RYTELO (imetelstat) is Geron's sole FDA-approved product and only source of product revenue (launched June 2024); its ability to reach/sustain profitability is wholly dependent on commercializing RYTELO in lower-risk MDS or expanding its indications.

“our ability to generate meaningful revenue from product sales and achieve profitability is wholly dependent on our ability to successfully commercialize RYTELO in the U.S. for lower-risk MDS or to expand its indications of use.”

Geron's manufacturing supply chain for RYTELO is highly specialized — it relies on a small group of third-party manufacturers and a single source for the active pharmaceutical ingredient (API); failure or loss of that source could halt supply of its only product.

“we are reliant upon a small group of third-party manufacturers to supply starting materials and drug product, and we rely on a single source to supply the API for RYTELO.”

Geron's Pharmakon Loan is secured by substantially all assets including its intellectual property, with covenants restricting operating/financial flexibility; default could let lenders seize the IP collateral — compounded by obligations under a Royalty Pharma agreement.

“All obligations under the Pharmakon Loan Agreement are secured by substantially all of our assets, including our intellectual property.”

Geron flags tariffs affecting pharmaceuticals and ingredients — a 10% baseline global tariff (April 2025) and reciprocal tariffs (Aug 2025); even after a Supreme Court ruling invalidating IEEPA tariffs, a 10% global tariff under Section 122 of the Trade Act of 1974 remained in place, raising potential input costs for its imported supply chain.

“In April 2025, the U.S. government imposed a 10% baseline global tariff and in August 2025, the U.S. imposed higher “reciprocal” tariffs on numerous other territories, including EU Member States and South Korea. While the U.S. Supreme Court recently issued a ruling invalidating tariffs imposed by the Trump administration under the International Emergency Economic Powers Act, other tariffs imposed by the U.S. government remain in place, including the 10% global tariff imposed by the Trump administration under Section 122 of the Trade Act of 1974”