Eltrombopag as steroid sparing therapy for immune thrombocytopenic purpura in systemic lupus erythematosus

Background Eltrombopag activates the thrombopoietin (TPO) surface receptor on the megakaryocyte, which increases the production of platelets, and rapidly improves circulating platelet numbers in patients with immune thrombocytopenic purpura (ITP). This allows for rapid tapering and/or cessation of corticosteroid therapy. Less is known about the platelet response to this drug in ITP associated with systemic lupus erythematosus (SLE). Methods A retrospective review was performed of the clinical course of three consecutive patients, each with SLE-associated ITP who were initially treated with corticosteroids or other immunomodulatory therapy. These patients were treated with eltrombopag at the DMC Center for Bleeding Disorders and Thrombosis. Eltrombopag was administered according the package insert, with an initial dose of 50mg daily, with weekly, then monthly monitoring of platelet counts and dose adjustments. Some immunomodulatory agents (e.g. hydroxychloroquine) were continued to control non hematologic SLE manifestations. Results All three patients maintained acceptable platelet counts (>50,000/mm(3) for >3 years) following tapering and cessation of corticosteroids. The drug was well-tolerated and there were no adverse events, and specifically no thrombotic events. Conclusion Eltrombopag is effective as a rapidly acting corticosteroid sparing therapy for patients with ITP associated with SLE. This is important in reducing corticosteroid related side effects and morbidities in treating SLE patients with ITP. Larger studies are needed to ascertain safety and efficacy of eltrombopag in SLE patients with ITP, particularly those with coexisting antiphospholipid antibodies.