Mycophenolate mofetil (MMF) is widely used to prevent acute rejection in adult solid organ transplant recipients, but data in children and adolescents are scarce. This prospective, multicenter, open-labeled, single-arm study investigated the efficacy and safety of an MMF-based immunosuppressive regimen in 100 pediatric renal transplant recipients over a 3-yr period of time. Three age groups were formed (<6 yr, n = 33; 6 to <12 yr, n = 34; 12-18 yr, n = 33). Basic immunosuppression consisted of MMF (600 mg/m(2) b.i.d), cyclosporin A microemulsion and corticosteroids. Seventy-three percent of patients were given anti-lymphocyte antibody induction therapy, of whom 74% received anti-thymocyte globulin. Patient and graft survival 3 yr after transplantation amounted to 98 and 95%, respectively. Twenty-five percent of all patients suffered a biopsy-proven acute rejection episode in the first 6 month post-transplant. Children undergoing induction therapy exhibited a numerically lower rejection rate (21 vs. 37%, p = 0.11). Three years after transplantation, the acute rejection rate added up to 30% (26% with induction therapy vs. 41% without induction therapy, p = 0.21). The number of patients with acute rejection was lowest in the youngest age group (18%), in comparison with 39% in the 6 to <12 yr and 33% in the 12-18 yr age group, respectively. For the entire patient population, the rate of patients who withdrew prematurely because of adverse events was low (12%). The present study shows that MMF therapy in pediatric renal transplant recipients leads to an excellent patient and graft survival 3 yr post-transplant with an acceptable safety profile.