IMerge, a two-part clinical trial, is evaluating Geron’s (GERN) imetelstat in transfusion-dependent patients with low- or intermediate-risk myelodysplastic syndromes who have relapsed after or are refractory to prior treatment with an erythropoiesis-stimulating agent. The first part is a Phase 2, open-label, single-arm trial for assessing the drug’s efficacy and safety.
The second part of the trial is to be a Phase 3, double-blind, randomized controlled trial in ~170 patients. Its primary efficacy endpoint is planned to be the rate of RBC-TI (red blood cell transfusion independence) for at least eight weeks. Key secondary endpoints are to be RBC-TI rates for 24 weeks, the amount of and changes in red blood cell transfusions, and hematologic improvement.
Janssen reviewed the trial’s internal data in September 2016 and April 2017. Preliminary data from IMerge’s first part showed that among the 32 patients enrolled, 13 who had not received prior treatment showed higher transfusion independence rates and durability. Janssen Biotech will be enrolling ~20 more patients to confirm the drug’s benefit-risk profile. Geron has not received a commitment from Janssen for beginning the second part of the IMerge trial and believes the latter will initiate it after an affirmative continuation decision.