Janssen starts phase 2/3 trial of imetelstat in myelodysplastic syndromes

Imetelstat, discovered by Geron, is a potent and specific inhibitor of telomerase that is administered by intravenous infusion.

The clinical trial, also referred to as the IMerge study, is the second study to be started under the global imetelstat license and collaboration agreement between Geron and Janssen Biotech.

Under the phase 2/3 clinical trial, imetelstat will be examined in transfusion dependent patients with International Prognostic Scoring System (IPSS) Low or Intermediate-1 risk MDS who have relapsed after or are refractory to prior treatment with an erythropoiesis-stimulating agent (ESA).

A total of about 200 patients are anticipated to be enrolled under the trial, which includes two parts.

About 30 patients are anticipated to be enrolled in part 1 of the trial. They will receive imetelstat and be followed for safety, hematologic improvement and reduction in transfusion requirement.

The data from part 1 should support a positive assessment of the benefit/risk profile of imetelstat in the patients in order to go ahead to part 2.

About 170 patients are expected to be enrolled in part 2, who will be assigned randomly, in a 2:1 ratio, to receive either imetelstat or placebo.

Geron said the primary efficacy endpoint is designed to be the rate of red blood cell transfusion-independence lasting around eight 8 weeks, defined as the proportion of patients without any red blood cell transfusion during any consecutive 8 weeks since entry to the trial.

A primary efficacy analysis is expected to take place 12 months after the final patient is enrolled.