Conversion to sirolimus with calcineurin inhibitor elimination vs. dose minimization and renal outcome in heart and lung transplant recipients

Sirolimus (SRL) has been used as an alternative immunosuppressant strategy to allow either dose minimization or complete withdrawal of calcineurin inhibitors (CNI) therapy to improve renal outcome. One hundred thirty-one heart and 55 lung transplant patients were converted from a CNI to SRL based immunosuppression, with CNI elimination in 25 patients, and dose reduction in 161 patients. Fifty-six (28%) patients died and 65 (33%) patients had a 25% or more decline in estimated glomerular filtration rate (eGFR) during a median follow-up of 18 months. The three groups (SRL only group n = 25; SRL + tacrolimus n = 94; SRL + cyclosporine n = 67) had an initial improvement in estimated glomerular filtration rate (p = 0.05), with subsequent similar slow decline in mean eGFR (repeated measures ANOVA, p = 0.96). After controlling for important potential confounding variables, the three groups had similar renal outcome (p = 0.40) and overall survival (p = 0.45). In conclusion, the benefits of CNI withdrawal vs, minimization as part of SRL-based regimens are similar with regard to renal outcomes and patient survival.