Exhibit 99.1 Geron Corporation Reports Third Quarter 2025 Financial Results and Recent Business Highlights Achieved $47.2 million in RYTELO® net product revenue in Q3 2025 Completed enrollment in Phase 3 IMpactMF clinical trial evaluating imetelstat in relapsed/refractory myelofibrosis Strengthened leadership team with appointment of Chief Commercial Officer and additional key executives Announced one oral and four poster presentations accepted at the American Society of Hematology (ASH) 2025 Annual Meeting ...