Clinical evidence on the use of anti-mTOR drugs in renal transplantation

Calcineurin inhibitor drugs (CNI) are the mainstay of modern immunosuppression in renal transplantation. However, they contribute significantly to the chronic loss of renal grafts and the high morbidity and mortality in this population due to their deleterious effects on the renal graft, cardiovascular profile and tumour pathology. Anti-mTOR drugs, sirolimus (SRL) and everolimus (EVE) are potent immunosuppressants with antiproliferative and anti-migratory capacities. These properties mean that they have a potential protective role in graft dysfunction, in renal function optimisation and the appearance of malignant tumours. Indeed, clinical trials and observational studies have demonstrated that conversion from CNI to anti-mTOR-based maintenance therapy has beneficial effects on transplant outcomes in terms of renal function, without significant increase in acute rejection rates. This review article examines the evidence of the use of anti-mTOR in the following clinical situations following renal transplantation: 1) prevention of immune dysfunction and renal function preservation in de novo renal transplantation and after early or late CNI withdrawal; 2) chronic dysfunction of the renal graft; 3) cardiovascular effects; 4) de novo post-transplant diabetes, and 5) de novo tumour pathology.