Advertise With UsAdvertise on our extensive network of industry websites and newsletters.
Get the PBR newsletterSign up to our free email to get all the latest PBR
news.GlaxoSmithKline has announced positive safety and efficacy results from Raise, a Phase III study of Promacta, in adults with chronic immune thrombocytopenic purpura who had received one or more prior idiopathic thrombocytopenic purpura therapies.
Subscribe to our email newsletter
According to the company, patients receiving Promacta were eight times more likely than those on placebo to maintain platelet counts between 50,000 to 400,000/microliters during a six-month treatment period, thereby reducing patients’ bleeding symptoms and their need for concomitant and rescue idiopathic thrombocytopenic purpura (ITP) treatments.
Raise, a global, six-month, double-blind, placebo-controlled, Phase III study was designed to evaluate the safety and efficacy of Promacta in previously treated adults with chronic ITP and with platelet counts less than 30,000/microliters.
The study enrolled 197 patients (Promacta: n=135; placebo: n=62) and, of these, approximately 50% had platelet counts less than or equal to 15,000/microliters; about 50% were receiving simultaneous ITP therapies at randomization; around 35% were splenectomized, and more than 50% had received at least three prior ITP medications.
Patients began once daily treatment with Promacta at 50mg with doses individualized based upon each patient’s platelet response, ranging from once-daily doses of 25mg to 75mg, or less frequently. The baseline median platelet count in both the placebo and the Promacta groups was 16,000/microliters.
Throughout the study, the median platelet count in the placebo group never exceeded 30,000/microliters. By contrast, after just one week, patients in the Promacta arm experienced a rise in their median platelet count to 36,000/microliters, with median platelet levels subsequently ranging from 52,000 to 91,000/microliters for the remainder of the study, meeting the study’s primary endpoint of odds of responding (platelets 50,000 to 400,000/microliters) during the six month treatment period.
In comparison to the placebo group, significantly fewer patients treated with Promacta had any bleeding or clinically significant (WHO Grades 2-4; p < 0.001) bleeding throughout the trial and more patients in the Promacta group (59%) stopped or reduced their simultaneous ITP medications than in the placebo group (32%; p = 0.016). In addition, during the treatment Phase of the study, fewer patients in the Promacta arm (19%) required rescue therapy compared with those in the placebo arm (40%, p = 0.001).
Paolo Paoletti, senior vice president of oncology R&D at GlaxoSmithKline (GSK), said: Promacta is the first approved agent to show that generating platelets can be achieved and maintained with an oral therapy. With the continued emergence of GSK in oncology, we want patients and physicians to continuously benefit from our dedication to developing truly innovative treatments that can help improve patients’ lives.