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Abstract

Aim Bortezomib has activity against mature plasma cells, the source of potentially harmful donor-specific antibody (DSA) and antibody-mediated rejection (AMR). We present the use of bortezomib in 2 children with AMR after heart transplant (Tx). Methods Case 1: 3 yo with repaired congenital heart disease (CHD) with VAD placed for ventricular dysfunction. 2 DSAs were present at Tx with X-match positive. Initial therapy with Simulect (induction), plasmapheresis (Px), and IVIG 2 gm/kg cleared DSA. 18 days later a new DSA appeared. C4d on biopsy was negative. IVIG was repeated. DSA levels later increased with positive C4d and hemodynamic change. Bortezomib protocol was started: 1.3 mg/m2 IV every 3-4 days for 4 doses, Solumedrol 5 mg/kg with each dose, Px prior to bortezomib dose then for 3 consecutive days 3 days after the last dose, and rituximab 375 mg/m2 the day before protocol started. Serial HLA antibody testing was performed. Case 2: 3 yo with CHD transplanted at 11 mo developed acute AMR following viral illness. Steroids and IVIG produced no response. Bortezomib protocol was started without rituximab. Results DSA MFIs over time are presented below. Tx = transplant; Px = pheresis; Bor = bortezomib. Case 1 [Fig. 1] Case 2 [Fig. 2]. Download : Download full-size image Download : Download full-size image Conclusions Bortezomib can be used successfully to treat early and late AMR associated with DSA. Neither patient has had recurrence of antibody after 1 year follow-up.