A case report of long-term complete remission following cessation of romiplostim dosing in a previously severe ITP patient.

Abstract

e17001 Background: Primary Immune thrombocytopenia(ITP) is a chronic autoimmune disorder characterized by low platelet counts and bleeding complications. Platelet destruction together with insufficient platelet production occur through an antibody-mediated process and early treatment options revolve around targeting antibodies and immunologic pathways. Such therapies may not produce long-term responses and may be accompanied by considerable adverse effects which can lead to complications and/or drug discontinuation. Romiplostim is a thrombopoietic agent that stimulates platelet production and offers an alternative method for treatment of patients with ITP. In clinical trials, patients have achieved durable platelet count responses without clinically important side effects. Methods: We report the case of a 44 year-old female with refractory ITP who has achieved successful remission following treatment with romiplostim. Results: As previously described in Haematologica (2008;93:1445) this patient presented with purpura, menorrhagia, and a platelet count of 7,000. Throughout 2005 she had only transient responses to high dose dexamethasone, intravenous immunoglobulin, rituximab, and splenectomy. She was placed on romiplostim in August 2005 as part of a clinical trial and received a dose of 7 mcg/kg/week for approximately 50 weeks. She was able to tolerate dose reductions and by May 2007 her dose had been de-escalated to 3 mcg/kg/week, which she continued through 2009 as part of an open-label continuation study. In January 2010, after completion of the clinical trial, she began receiving romiplostim by prescription. She was able to gradually tolerate extended dosing intervals due to sustained platelet response. Her last dose was administered on October 27, 2010 and she has maintained a platelet count above 197,000 without further therapy. Conclusions: This case represents, to our knowledge, one of the longest maintained durable responses to romiplostim therapy. Romiplostim provides an alternative approach of treatment for ITP, and as evidenced by this case report, in some patients it may also lead to disease remission and eliminate the need for further treatment.