Long-Term Follow-Up of De Novo Use of mTOR and Calcineurin Inhibitors After Kidney Transplantation

BACKGROUND Long-term efficacy and safety of de novo use of the mammalian target of rapamycin inhibitors (mTORi) have been evaluated primarily using registry data. METHODS This was a pooled retrospective analysis of data obtained from 10 prospective randomized trials in de novo kidney transplant recipients (n = 581) receiving calcineurin inhibitors (CNIs) combined with sirolimus (n = 329), everolimus (n = 128), or antimetabolites (n = 124). RESULTS There were no differences in patient (84.5 versus 80.9 versus 89.7%, P = 0.996), graft (65.4 versus 59.5 versus 73.1%, P = 0.868), and biopsy-confirmed acute rejection-free (78.1 versus 77.3 versus 79.0%, P = 0.976) survivals, respectively. The incidence of cytomegalovirus infection was lower (6 versus 3 versus 11%, P = 0.024) but treatment discontinuation was higher among patients receiving mTORi (66.0 versus 47.7 versus 31.5%, P < 0.001), respectively. At 5 years, median estimated glomerular filtration rate (49.6 versus 43.9 versus 53.2 mL/min, P = 0.006) was lower and the proportion of patients with proteinuria (53 versus 40 versus 23%, P < 0.001) was higher among patients receiving mTORi, respectively. CONCLUSIONS The efficacy of de novo use of mTORi is comparable with that of antimetabolites in kidney transplant recipients receiving calcineurin inhibitor. Apart from the lower cytomegalovirus infection rate, the safety profile is unfavorable, showing higher treatment discontinuation rates and higher incidence of proteinuria.