Rescue immunosuppression with mammalian target of rapamycin inhibitor drugs in liver transplantation

Abstract

Background: Mammalian target of rapamycin (mTOR) inhibitors behave as potent immunosuppressants, which have the advantages, with respect to calcineurin inhibitors (CNI; cyclosporine or tacrolimus), of no nephrotoxicity but inhibition of cell proliferation. They are particularly suitable for patients with renal insufficiency or neoplasias.

Materials and methods: Twenty-eight liver transplant patients were immunosuppressed with everolimus or sirolimus as rescue therapy after CNI treatment: 8 hepatocellular carcinomas; 7 de novo malignancies; 6 renal insufficiencies; 3 chronic rejections; 3 acute rejection episodes; and 1 epilepsy.

Results: There were 0% tumor recurrences, 50% improvements in 33% no change, and 17% worsening of renal function among cases of renal insufficiency; 0% improvement in cases of chronic rejection, and 33% improvement in acute rejection episodes. There was a 7% incidence of acute rejection episodes, but no kidney failure, gastrointestinal intolerance, hydrocarbon intolerance, hypertension, or arterial or venous thrombosis. Diarrhea occurred in 7%; hypercholesterolemi in 46% hypertriglyceridemia in 50% thrombocytopenia in 14%, leukopenia in 14%, and anemia in 39%. The 12% intercurrent infection rate included oral thrush in 11%. Lower limb edema occurred in 21%; 1 case displayed facial edema and 1, alopecia.

Conclusions: mTOR inhibitors were safe immunosuppressive drugs whose side effects were controlled and easily managed. They have advantages with respect to CNI due to their slight effects on kidney function and lack of promotion of diabetes mellitus. Although their long-term effectiveness for control of neoplastic diseases is yet to be seen, they can be used safely in these patients with a low incidence of rejection. Their effectiveness to control steroid-resistant acute rejection episodes or renal insufficiency seems significant, but they are of doubtful benefit for chronic rejection.