Dose reduction and discontinuation of mycophenolate mofetil (MMF) therapy because of gastrointestinal complications has been associated with increased risk of acute rejection episodes and graft loss. Enteric-coated mycophenolate sodium (EC-MPS) delays release of mycophenolic acid (MPA), and was designed to reduce MPA-related gastrointestinal adverse events. Data comparing the efficacy of EC-MPS vs MMF in de novo renal transplant (RTx) recipients from large prospective studies are limited. Therefore, a pooled data analysis was performed based on 1891 de novo RTx recipients receiving EC-MPS (n = 1289) or MMF (n = 602) plus cyclosporine and steroid therapy in 4 prospective multicenter studies with similar entry criteria. In all trials, the initial dose of EC-MPS was 1440 mg/d, and of MMF was 2000 mg/d; both dosages deliver equimolar amounts of MPA. Induction therapy was permitted in 2 studies per center practice. Multivariate logistic regression analysis was performed, adjusting other potential explanatory variables including recipient age, sex, and race/ethnicity; induction therapy; and diabetes mellitus at baseline. In addition, propensity scores were used to explain potential bias. Mean (SD) MPA dose (EC-MPS dosage was converted to MMF equivalent) during months 0 to 12 was similar: EC-MPS, 1820 (370) mg/d, vs MMF, 1860 (290) mg/d. However, at univariate and multivariate analyses, the rates of treatment failure, biopsy-proved acute rejection episodes, and graft loss were significantly lower with EC-MPS compared with MMF at month 12. In conclusion, this pooled analysis documents a substantial improvement in efficacy in de novo RTx recipients receiving EC-MPS vs MMF with concomitant cyclosporine and steroid therapy.