©© 2007 American College of Clinical Pharmacology, Inc.
The Journal of Clinical Pharmacology
, 10.1177/0091270007301624
Pharmacokinetics and Pharmacodynamics of Mycophenolic Acid After Enteric-Coated Mycophenolate Versus Mycophenolate Mofetil in Patients With Progressive IgA Nephritis
David Czock 1,
Franz Maximilian Rasche 1,
Alexander Carius 1,
Petra Glander 2,
Klemens Budde 2,
Steffen Bauer 2,
Frieder Keller 3*,
and
Lutz von Müller 4
1 University Hospital Ulm, Germany
2 Charite University Hospital, Berlin, Germany
3 University Hospital of Ulm, Germany
4 University of Saarland Hospital, Homburg/Saar, Germany
* To whom correspondence should be addressed. E-mail: frieder.keller{at}uni-ulm.de.
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Abstract |
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Mycophenolic acid can be administered orally using mycophenolate mofetil or enteric-coated mycophenolate. In renal transplant patients on immunosuppressant combination therapy, the overall mycophenolic acid exposure after oral dosing with mycophenolate mofetil and enteric-coated mycophenolate is similar. This study compared pharmacokinetics and pharmacodynamics of mycophenolic acid after equivalent doses of enteric-coated mycophenolate (360 mg twice daily) or mycophenolate mofetil (500 mg twice daily) in 7 patients with progressive IgA nephritis (glomerular filtration rate 20-35 mL/min) using a randomized crossover design. The pharmacokinetics of mycophenolic acid concentrations and pharmacodynamics (using inosine 5'-monophosphate dehydrogenase activity as a bio-marker) were sequentially monitored for 12 hours. After enteric-coated mycophenolate treatment, the mycophenolic acid peak concentration (Cmax = 12.8 vs 6.0 µg/mL, P < .05) and the overall exposure were significantly higher (AUC = 60.9 vs 40.7 µg·h/mL, P < .05), and the apparent clearance was significantly lower (CL/F = 7.9 vs 10.7 L/h, P < .05) as compared to that after mycophenolate mofetil. Paradoxically, inosine 5'-monophosphate dehydrogenase activity was not significantly different. In conclusion, the steady-state mycophenolic acid exposure was higher during treatment with enteric-coated mycophenolate as compared to mycophenolate mofetil, which might be explained by more extensive enterohepatic recycling of mycophenolic acid after administration of enteric-coated mycophenolate, whereas inosine 5'-monophosphate dehydrogenase suppression was not different.