Safety and efficacy of everolimus after kidney and hematopoietic stem cell transplantation

Background: The aim of this retrospective study was to investigate the efficacy of everolimus at our institution and to report incidence and type of side effects in patients who underwent kidney transplantation or hematopoietic stem cell transplantation (HSCT). Material/Methods: Electronic medical records were evaluated for 122 patients (76 men and 46 women) treated with everolimus between January 2000 and January 2009. Of these patients, 81 had undergone kidney transplantation (mean age: 56 +/- 12 years) and 41 patients were treated with HSCT (mean age: 47 +/- 11 years). Results: Everolimus was discontinued in a total of 53% of patients (n=64) with no difference observed in kidney transplant recipients vs. stem cell transplanted patients (p=0.85). In one half of the patients, cessation of the drug was due to a lack of long-term efficacy (n=32). In the other half, everolimus was discontinued due to side effects (n=32). However, patients with side effects had no elevated everolimus concentrations (5.5 +/- 2.3 vs. 5.2 +/- 1.7 ng/ml; p=0.39). Pneumonitis (n=5) or proteinuria over 1.5 g per day (n=13) were only observed in kidney transplant patients, while polyomavirus- induced cystitis (n=3) and thrombotic thrombocytopenic purpura (n=7) were only observed in stem cell transplanted patients. Conclusions: Everolimus was an effective immunosuppressive agent in half of the patients. A quarter of all patients developed side effects resulting in discontinuation of the drug. The profile of side effects in kidney recipients clearly differs from hematopoietic stem cell transplanted patients.