Study to Evaluate Imetelstat (GRN163L) in Subjects With International Prognostic Scoring System (IPSS) Low or Intermediate-1 Risk Myelodysplastic Syndrome (MDS)

The purpose of this study is to evaluate the efficacy and safety of imetelstat in transfusion dependent participants with low or intermediate-1 risk myelodysplastic syndrome (MDS) that is relapsed / refractory to erythropoiesis-stimulating agent (ESA) treatment.

Inclusion Criteria

• Man or woman greater than or equal to (>=) 18 years of age
• In Part 1, diagnosis of myelodysplastic syndrome (MDS) according to World Health Organization (WHO) criteria
• International Prognostic Scoring System (IPSS) low Risk or intermediate-1 risk MDS
• Red blood cell (RBC) transfusion dependent, defined as requiring at least 4 RBC units transfused over an 8-week period during the 16 weeks prior to Study Entry; pre-transfusion hemoglobin (Hb) should be less than or equal to 9.0 gram per deciliter (g/dL) to count towards the 4 units total
• Eastern Cooperative Oncology Group (ECOG) performance status 0, 1 or 2

Exclusion Criteria

• Participant has known allergies, hypersensitivity, or intolerance to imetelstat or its excipients
• Participant has received an investigational drug or used an invasive investigational medical device within 30 days prior to Study Entry or is currently enrolled in an investigational study
• Prior treatment with imetelstat
• Have received corticosteroids greater than (>) 30 milligram per day (mg/day) prednisone or equivalent, or growth factor treatment within 4 weeks prior to study entry
• a) Prior treatment with a hypomethylating agent (example [eg], azacitidine, decitabine); b) Prior treatment with lenalidomide; c) Has received an erythropoiesis-stimulating agent (ESA) or any chemotherapy, immunomodulatory, or immunosuppressive therapy within 4 weeks prior to study entry (8 weeks for long-acting ESAs)

This is a Phase 2/3, multicenter study of imetelstat that consists of 2 parts. Part 1 is an open-label, single-arm design to assess the efficacy and safety of imetelstat. Approximately 55 participants will be enrolled in Part 1, including the expansion cohort, and be followed-up for safety, hematologic improvement and reduction in transfusion requirement. Part 2 of the study will be initiated if data from Part 1 are supportive of a satisfactory benefit/risk profile. Part 2 is a double-blind, randomized design to compare the efficacy of imetelstat with placebo. Approximately 170 eligible participants will be randomized in a 2:1 ratio to receive either imetelstat or placebo, respectively. Each part of the study will consist of 3 phases: a Screening phase (up to 28 days); a treatment phase; and a post-treatment follow-up phase which will continue until death, lost to follow-up, withdrawal of consent, or the End of the Study (whichever occurs first). The End of the Study is defined as 2 years after the study entry of the last participant or anytime the sponsor terminates the study, whichever comes first.

Lead Organization
Geron Corporation