Bortezomib for Refractory Immune-Mediated Thrombocytopenia Purpura

Abstract

The treatment of refractory immune-mediated thrombocytopenia purpura (ITP) can be challenging. This case report describes treatment of refractory ITP with bortezomib, a proteasome inhibitor. This strategy has been successful in relapsing thrombotic thrombocytopenic purpura but is a novel therapeutic approach for ITP. Further research use of proteasome inhibition in refractory ITP may be warranted.

Figure 1. Hospital and Outpatient Interventions for Index Case

Inverventions: Arrows and letters indicate interventions: a= therapeutic plasma exchange, b= bortezomib (1.3 mg/m² subcutaneously days 1, 4, 8 and 11, c= rituximab 375 mg/m² IV × 4 doses, d= dexamethasone 40 mg PO daily × 5 days decreased to prednisone 20 mg PO daily, e= eltrombopag, dose range 25–75 mg PO, f= romiplostim, dose range 2–10 mcg/kg. When e or f are used this indicates a change in dose or cessation of drug. A) patient was started on therapeutic plasma exchange dates indicated by arrow and letter. When platelet response was not sustained, bortezomib was started. B) after discharge patient had platelet counts monitored weekly. She was given weekly romiplostim until platelet counts were satisfactorily elevated, then eltrombopag was also decreased. She developed refractory thrombocytopenia. C) patient was admitted. She was continued on eltrombopag and received bortezomib and therapeutic plasma exchange. Romiplostim was resumed. On count recovery she was discharged. D) as outpatient she continues to have robust counts. She continues to take eltrombopag and gets romiplostim if platelet count decreases below 125,000/µL.