Adapted from:Kuter et al. Efficacy of romiplostim in patients in…

Question Adapted from:Kuter et al. Efficacy of romiplostim in patients in… Adapted from:Kuter et al. Efficacy of romiplostim in patients in patients with chronic immune thrombocytopenic purpura: a double-blind randomised controlled trial. Lancet 2008; 371:395-403.AbstractObjective- To assess the efficacy of romiplostim in preventing relapse of chronic immune thrombocytopenic purpura (ITP) in splenectomized and non-splenectomized patients.Background- ITP is a disorder involving platelets (a blood cell responsible for clotting). It is characterized by accelerated platelet destruction and decreased platelet production in the bone marrow. Therefore, patients with ITP often have dangerously low platelets, which puts them as risk for bleeding. While a platelet count in a healthy individual ranges from 150-450×109/L, patients with ITP often have platelets<30x109/L. If platelet counts in these individuals do reach normal levels, they are at high risk for relapse. Romiplostim, a novel agent that simulates the bone marrow to produce more platelets, has been useful in previous trials in preventing relapse of ITP. Research Design and Methods- They conducted two parallel, multicenter, international phase III studies that were randomized, placebo-controlled, double-blind trials, lasting for 6 months. Patients who have been diagnosed with ITP but were in remission at baseline were enrolled into both studies. These two studies were identical except that one trial enrolled patients who had undergone a surgical procedure to remove their spleen (splenectomy) 4 weeks or more before entry and the other group had not undergone a splenectomy. The eligibility criteria for both studies were identical: a previous diagnosis of ITP, a baseline mean platelet count more than 30x109/L (which means they were in remission), age 18 years or older, no active malignancy. Patients were randomized 2:1 to receive subcutaneous injections of romiplostim or placebo every week for 24 weeks. Both romiplostim and placebo were supplied in identical vials containing a lyophilized powder that was reconstituted with sterile water for subcutaneous injection. After reconstitution, both vials contained 10 mM histidine, 4% mannitol, 2% sucrose, and 0.004% polysorbate 20. Placebo vials did not contain the 0.5 mg/mL romiplostim protein that was present in romiplostim vials. All patients were monitored weekly for a relapse of ITP (which was defined as a platelet count <30 x109/L). Results- Sixty-three splenectomized (n=42 treatment, n=21 placebo) and 62 non-splenectomized patients (n=41 treatment, n=21 placebo) with ITP were enrolled. Relapse was observed in 9 of 42 splenectomized patients given romiplostim versus 8 of 21 given placebo. In non-splenectomized patients, relapse was observed in 18 of 41 patients who received romiplostim compared to 12 of 21 in the placebo group. Conclusion-Relapse of ITP was lower among patients who received romiplostim compared to patients who receive placebo. Stimulation of platelet production by romiplostim may provide a new therapeutic option for patients with ITP.1. Identify the:Study population  Primary outcome  Control group  Intervention group(s)  Study Question  2. Calculate the absolute risk reduction (ARR), the relative risk reduction (RRR), and the number need to treat (NNT) for the: Patients who have undergone a splenectomy       Patients who have not undergone a splenectomy       3. Is it possible to determine the clinical significance and/or statistical significance of these results? Please explain.                             Health Science Science Nursing Share QuestionEmailCopy link Comments (0)