SB-497115 (Oral Thrombopoietin Receptor Agonist) Versus Placebo In Adults With Refractory Immune Thrombocytopenic Purpura (ITP)

This study is a double-blind, randomized, placebo-controlled, parallel group, repeat-dose, study conducted in two parts (Part A and Part B) examining 30, 50, and 75 mg doses of SB-497115-GR as a treatment for patients with ITP who have failed prior therapy. The study is designed to determine the proportion of patients with a platelet count =50,000/µL after 42 days. In Part B, 99 newly-recruited subjects will be randomized to one of two dosing arms in a 2:1 ratio of active:placebo. During the 6 week study period, subjects will start on placebo or active drug (50 mg) and may have a dose increase to 75 mg based upon their platelet count at day 22.