Imetelstat: First Approval.

Imetelstat (RYTELO™), an oligonucleotide telomerase inhibitor, is being developed by Geron Corporation for the treatment of myeloid hematologic malignancies. In June 2024, imetelstat was approved in the USA for use in adult patients with low- to intermediate-1 risk myelodysplastic syndromes (MDS) with transfusion-dependent anemia requiring 4 or more red blood cell units over 8 weeks who have not responded to or have lost response to or are ineligible for erythropoiesis-stimulating agents (ESA). This article summarizes the milestones in the development of imetelstat leading to this first approval for the treatment of adult patients with low- to intermediate-1 risk MDS with transfusion-dependent anemia.