Introduction: Enteric-coated mycophenolate sodium (EC-MPS) is the enteric-coated salt form of mycophenolic acid (MPA), the active component of the prodrug mycophenolate mofetil. EC-MPS was developed to reduce the upper-gastrointestinal (GI) effects of mycophenolate mofetil. There are no studies available comparing trough plasma levels in patients with GI intolerance to MMF when they are converted to EC-MPS.
Aim: To compare the GI tolerance and the MPA levels in patients previously treated with MMF in whom this drug was replaced by EC-MPS.
Materials and methods: A prospective study was conducted in 133 renal transplant patients after conversion from MMF to EC-MPS (median time posttransplant 42 months, range 1 to 240 months). The causes for EC-MPS switching were GI intolerance to MMF (51.9%; group A), low trough plasma levels with MMF (29.3%; group B), and others (18.8%; group C). These patients were converted to equipotent doses of EC-MPS.
Results: The trough plasma MPA levels increased from 1.5 +/- 1.1 microg/mL at baseline to 2.5 +/- 2.0 microg/mL at 1 month postconversion despite the equipotent EC-MPS doses not being increased. These higher plasma levels were maintained throughout the study. In group A, this increase was from 1.8 +/- 1.0 to 2.7 +/- 2.1 microg/mL (P = .01) and in group B from 0.8 +/- 0.4 to 2.4 +/- 1.4 microg/mL (P < .001). The doses and levels of calcineurin inhibitor decreased from baseline. Creatinine clearance improved from 56.5 +/- 24.7 mg/dL at baseline to 61.9 +/- 28.6 at 6 months postconversion (P = .02). There was a statistically significant increase in hemoglobin levels. In group A, the GI tolerance improved in 78% of the patients.
Conclusions: At equipotent doses, patients converted to EC-MPS have higher and more adequate levels of MPA. At 6 months postconversion, we observed an improvement of the renal function, probably due to a reduction of calcineurin inhibitor drugs. However, the possibility that a better immunosuppressive efficacy as demonstrated by more suitable trough plasma levels may have been a contributing factor cannot be discarded.