Sirolimus Monotherapy Versus Sirolimus in Combination with Steroids and/or MMF for Immunosuppression After Liver Transplantation

Calcineurin inhibitor (CI)-associated renal dysfunction has emerged as a major cause of morbidity and mortality after liver transplantation. In this retrospective study, we compared the efficacy, safety, and renal protective effect of sirolimus monotherapy (Group A; n=26) with sirolimus in combination (Group B; n=34) with steroids and/or mycophenolate mofetil (MMF) in liver transplant recipients who were switched from CI. Patients were switched abruptly or over a period of 2–4 weeks and followed for 17±10 months. Preconversion renal biopsies in five of six patients showed histological features consistent with CI nephrotoxicity. Serum creatinine increased in the year prior to conversion from 1.7±0.4 to 2.1±0.7 mg/dl (P=0.009) and improved thereafter (1 month, 1.7±0.6, P < 0.001; 6 months, 1.6±0.5, P < 0.001; last follow-up, 1.7±0.9, P=0.02); only four patients showed a significant decline in renal function after conversion. Seven (11.3%) patients experienced acute rejection (Group A, two; Group B, five; P=NS) and this resulted in the discontinuation of sirolimus in one patient. Fifty-four adverse events occurred in 40 (67%) patients, with similar numbers of adverse events in Group A and Group B. Most episodes of rejection (5/7; 71%), adverse events (45/54; 83%), and discontinuations (5/8; 63%) occurred within 6 months of conversion. We conclude that both sirolimus monotherapy and sirolimus in combination with prednisone and/or MMF are efficacious and safe in liver transplant recipients. Conversion to sirolimus was associated with an immediate improvement in renal function that was sustained during the follow-up.