[Rapamycin: a new immunosuppressive agent capable of inhibiting chronic rejection?].

Chronic rejection represents the most common cause of transplanted graft loss in the long term. Rapamycin (sirolimus), and it's derivate RAD, are new and potent, immunosuppressive drugs. They inhibit cell proliferation driven by various growth factors. These drugs were successfully tested in some experimental models of the chronic rejection. Results of the first clinical trials have defined rapamycin pharmacokinetics and proved immunosuppressive efficacy. Rapamycin acts synergistically with cyclosporin A. The side effects are a dose-dependent thrombocytopenia and leukopenia but the most frequent is hyperlipidemia. The question, if rapamycin and RAD inhibit development of chronic rejection in man, will be solved by the prospective clinical trials over years.