[Romiplostim: an advance in the treatment of idiopathic thrombocytopenic purpura]

Primary Immune thrombocytopenia or idiopathic thrombocytopenic purpura (ITP) is an acquired immune disorder presenting with abnormal hemorrhagic symptoms resulting from a decrease in the number of platelets. The disorder used to be attributed to increased destruction of platelets mediated by antibodies. In the past few years, the description of its etiopathology has changed. A deficiency in the marrow production of thrombocytes has been demonstrated; because it is associated with increased peripheral platelet destruction, the deficiency cannot be compensated. These findings have justified the realization of studies assessing the utility of second generation thrombopoietin analogues for the treatment of these patients. These drugs include romiplostim or AMG 537 (Nplate), a peptidic analogue that stimulates the thrombopoietin receptor and induces an increase In the production and differentiation of megakaryocytes. Data obtained from the clinical trials that led to the authorization and subsequent follow-up describe romiplostin as an effective and safe drug for adult patients with chronic ITR The overall response rate is 94%; despite variations in the levels of platelets throughout treatment, 50% of patients maintain the response 95% of the time, and 78% of patients discontinue or significantly reduce the use of rescue treatment. The most common adverse event is headache. Reticulin fibrosis has been described, which is reversible after treatment discontinuation.