Muromonab-CD3 therapy for refractory rejections after liver transplantation: A single-center experience during two decades in Japan

Background/purpose: Refractory rejections still occur in the liver transplantation (LT) field. The aim of this study was to investigate significant factors for the introduction of therapy with muromonab-CD3 (MCD3) after LT. Methods: A total of 1415 LT patients were retrospectively evaluated, and 11 of the recipients received MCD3 therapy because of steroid-resistant rejections. The clinical factors before LT and before MCD3 therapy were investigated. Results: The recipients were retrospectively divided into two groups based on responses to MCD3 therapy, including their clinical courses after MCD3 therapy and their outcomes. The MCD3 therapy had positive effects in LT recipients with the following four factors: low score of model for end-stage liver disease or pediatric end-stage liver disease; earlier time point of the first incidence of rejection; more frequent steroid pulse therapy (SPT) within 2 weeks after LT; and the expression of CD3 in the peripheral blood before MCD3 introduction. Conclusion: Optimal induction of MCD3 triggered recovery from refractory rejections, especially in LT recipients in a stable condition, but not in those in a critical or compromised condition.