Safety and efficacy of thrombopoeitin mimetics for refractory immune thrombocytopenia purpura in patients with systemic lupus erythematosus or antiphospholipid syndrome: a case series

Background While thrombopoeitin (TPO) agonists that act to simulate platelet production have been approved for use in steroid-refractory chronic immune thrombocytopenia purpura (ITP), there are few data on the safety and efficacy of these medications in patients with concurrent systemic lupus erythematosus (SLE) or antiphospholipid syndrome (APS). Given that these agents can increase all hematopoietic cell lineages, it is unclear if there is an increased risk for exacerbation of the underlying lymphocyte-driven autoimmune disease in this population. Case summaries This case series includes four patients with SLE, one with concurrent APS, who were treated for steroid-refractory ITP with TPO mimetics at the University of Virginia between 2005 and 2015. In three of the four cases the medication was successful in improving platelet counts and preventing bleeding events. In addition, none of the patients experienced thrombosis or worsening of their underlying autoimmune disease. Conclusions This case series suggests that TPO mimetics are safe and moderately effective in patients with ITP in the setting of SLE or APS and do not contribute to increased disease activity.