A retrospective study of conversion from tacrolimus-based to sirolimus-based immunosuppression in orthotopic liver transplant recipients

Objectives: Calcineurin inhibitors are used widely in liver transplant recipients. Sirolimus is a new, potent immunosuppressant considered to be nonnephrotoxic. There is limited experience with the use of sirolimus in liver transplant recipients. This study aimed to investigate the clinical experience of conversion from tacrolimus-based to sirolimus-based immunosuppression in liver transplant recipients. Patients switched to cyclosporine-based immunosuppression during the same period were enrolled as controls. Materials and Methods: This retrospective study examined liver transplant recipients who had been switched fromtacrolimus-based to sirolimus-based or cyclosporine-based immunosuppressive therapy between January 2004 and January 2007 in the first affiliated hospital of Sun Yat-sen University. Patients were divided into 3 groups: those switched to sirolimus-based immunosuppression owing to acute rejection (group SIR-AR; n=11); those switched to sirolimus-based immunosuppression owing to renal insufficiency (group SIR-RI; n=18), and those switched to cyclosporine-based immunosuppression owing to acute rejection (group CsA-AR; n=15) Results: In patients switched owing to acute rejection, the rate of successful conversion was 54.5% in group SIR-AR (6/11) compared with 60% in group CsA-AR (9/15); this difference was not statistically significant (P > .05). After conversion, renal function in patients in group SIR-AR remained normal. Conversely, renal function in patients in group CsA-AR became abnormal 3 months after conversion. In patients who were switched owing to renal insufficiency in group SIR-RI, renal function improved significantly after conversion (P < .05). In the sirolimus groups, some sirolimus-associated adverse effects occurred but were limited and well controlled. Conclusions: Sirolimus can be used safely in liver transplant recipients. In the early stages after liver transplant, sirolimus combination therapy is recommended to prevent acute rejection. For patients with tacrolimus-related adverse effects, a sirolimus-based immunosuppression regimen is a rescue therapy.