Rituximab投与ABO血液型不適合生体肝移植における安全性と有効性に関する後方視的調査研究

抄録

【Objective】To estimate a standard dosage of rituximab prophylaxis for ABO incompatible living donor liver transplantation (ABO-I LDLT), we retrospectively investigated rituximab dosage, efficacy and safety in 37 patients including 4 children undergoing ABO-I LDLT with rituximab prophylaxis in 15 centers in 2013.
【Methods】We analyzed the data collected by questionnaire that were sent to registered surgeons or hepatologists of the Japanese Liver Transplantation Society.
【Results】Doses of rituximab in adult patients were 500 mg/body in 16 cases (48%), 375 mg/m² in 12 cases (36%) and 300 mg/body or 100 mg/body in 5 cases. The number of administration was one in 29 cases (89%). The scheduled timing of initial administration was 2 weeks of operation or earlier in 14 centers (93%), and the median of actual timing was 14 days prior to transplantation. One-year patient survival rate was 82%, and the incidence of antibody-mediated rejection (AMR) was 9%. Patients with a standard regimen consisting of 500 mg/body or 375 mg /m² rituximab 2 weeks before operation or earlier had significantly better one-year survival rate compared to a non-standard regimen consisting of 100mg/body or 300mg/body rituximab later than 2 weeks (100% vs. 70%, p = 0.009) and a lower incidence of AMR (0% vs. 15%, p=0.074). ABO-I LDLT with rituximab prophylaxis was well tolerated.
【Conclusion】The recommended regimen for rituximab prophylaxis is a single dose of 375 mg/m² body surface area 2 weeks before transplantation or earlier. The dose should be reduced carefully according to patient condition.