Descriptive Retrospective Comparative Study Between Two Brands of Mycophenolate Mofetil Used in Uruguay: Innovator Versus Generic (Suprimun)

BackgroundAccording to our experience, survival of cadaveric renal graft in 5 years increased from 63% as of the introduction of cyclosporine to 73% after azathioprine was substituted with mycophenolate mofetil (MMF) in 1997. Until 2003, the innovator mycophenolate mofetil (IMMF) (Cellcept; Roche) was used. In 2003, Laboratorios Clausen introduced in Uruguay a generic MMF (GMMF) (Suprimun/Micoflavin/Myclausen; Laboratorios Clausen) with previous bioequivalence studies. Since then, every health care provider administers one of these types of MMF available on the market to its renal transplant (RT) patients.MethodsWe compared the evolution of 2 groups of patients and their grafts, those treated with GMMF or with IMMF. This was a descriptive, retrospective, nonrandomized, comparative study that involved all transplant patients in a center from January 2005 to June 2010 from 2 different health care providers which administered GMMF or IMMF uninterruptedly. Patients were older than 18 years, underwent their first RT and received triple immunosuppressive regime with calcineurin inhibitor (CNI), corticoids, and MMF, and completed ≥6 months of post-RT evolution.ResultsThe GMMF group included 29 patients and the IMMF group 23. Patients from both groups had no significant differences (NS) regarding age, sex, diabetes, hepatitis C virus (HCV), recipient hypertension, donor type (living or cadaveric, sex, age, cause of death), or mismatch degree. There were no material differences regarding antibody induction, CNI type, day of diuresis, or function recovery percentage. Statistically different results were reported for time in dialysis (6.1 ± 0.7 y in IMMF vs 3.8 ± 0.5 y in GMMF) and cadaveric donor cold ischemia time (989 ± 205 min vs 851 ± 219 min, respectively). For IMMF and GMMF, respectively, clinical acute rejection was 40.9% and 31% and creatinine over 3, 6, 12, 24, 36, and 48 months, respectively, was (mg%): 1.65 ± 0.12, 1.66 ± 0.15, 1.43 ± 0.10, 1.44 ± 0.12, 1.49 ± 0.18, and 1.41 ± 0.17 and 1.50 ± 0.08, 1.41 ± 0.07, 1.63 ± 0.26, 1.31 ± 0.08, 1.26 ± 0.09, and 1.21 ± 0.10, with 22/28, 22/28, 22/28, 22/26, 19/20, 17/11, and 15/9 patients under follow-up (NS). Patient survival over 3, 6, 12, and 18 months, respectively, was 94%, 94%, 94%, and 94% and 96%, 96%, 96%, and 96%, and graft survival was 94%, 89%, 89%, and 89% and 96%, 93%, 93%, and 93% for IMMF and GMMF, respectively (NS). Dosing adjustment frequency and substitution with mycophenolate sodium was similar for both groups.ConclusionsWith the results of this preliminary study we can not reach any final conclusion regarding assistance practice. From both groups, which involved similar baseline variables except for time in dialysis and cold ischemia (both greater in IMMF), we could gather a similar graft and patient evolution. New prospective, randomized, double-blind studies involving an adequate number of patients will help to determine the efficacy of GMMF in renal transplantation.