A Three-part Study of Eltrombopag in Thrombocytopenic Subjects With Myelodysplastic Syndromes or Acute Myeloid Leukemia

Study Summary

This was a worldwide, three-part (Part 1: open-label, Part 2: randomized, double-blind, Part 3: extension), multi-center study to evaluate the effect of eltrombopag in subjects with myelodysplastic syndromes (MDS) or acute myeloid leukemia (AML) who have thrombocytopenia due to bone marrow insufficiency from their underlying disease or prior chemotherapy. This objective was assessed by a composite primary endpoint that consists of the following: the proportion of ≥Grade 3 hemorrhagic adverse events, or platelet counts \<10 Gi/L, or platelet transfusions. Patients with MDS or AML and Grade 4 thrombocytopenia due to bone marrow insufficiency from their underlying disease or prior chemotherapy were enrolled in the study. No low or intermediate-1 risk MDS subjects were enrolled in the study. Subjects must have had at least one of the following during the 4 weeks prior to enrolment: platelet count \<10 Gi/L, platelet transfusion, or symptomatic hemorrhagic event. Supportive standard of care (SOC), including hydroxyurea, was allowed as indicated by local practice throughout the study. The study had 3 sequential parts. Subjects who were enrolled in Part 1 (open-label) cannot be enrolled in Part 2 of the study (randomized, double-blind); however, subjects who completed the treatment period for Part 1 or Part 2 (8 and 12 weeks, respectively) continued in Part 3 (extension) if the investigator determined that the subject was receiving clinical benefit on treatment.

Primary Outcome

A participant was considered as a responder if he/she met the following response criteria: a Baseline platelet count \<20 Giga cells per liter (Gi/L) and a post-Baseline increased to \>20 Gi/L and at least 2 times the Baseline value; or a Baseline platelet count \>=20 Gi/L and a post-Baseline absolute platelet count increased to \>=50 Gi/L and at least 2 times the Baseline value. The response criteria was evaluated at each visit. Increase in platelet count observed up to 3 days after a platelet

Interventions

• DRUG placebo
• DRUG eltrombopag