Impairment of mycophenolate mofetil absorption by iron ion

Objective: We sought to evaluate the effect of iron ion on the absorption of mycophenolate mofetil, which is an immunosuppressive agent. The pharmacokinetics of mycophenolic acid were studied. Methods: A randomized crossover design with two phases was used. A 7-day washout period separated the two treatment conditions. In the first phase, the volunteers received 1.0 g of mycophenolate mofetil alone (study 1); in the second phase, the volunteers received 1.0 g of mycophenolate mofetil and 2 tablets of iron ion preparations concomitantly (study 2), The serum concentration of mycophenolic acid, which is a pharmacologically active metabolite, was measured by reverse-phase HPLC, Results: The area under the plasma concentration-time curve from 0 to 12 hours and the maximum concentration of mycophenolic acid in study 2 were significantly less than in study I (area under the curve, 32.9 +/- 14.7 versus 2.92 +/- 0.883 mug . h/mL, P < .001, maximum concentration, 20.1 +/- 9.21 versus 1.30 +/- 0.367 <mu>g . h/mL, P < .001), Conclusions: This finding shows that when mycophenolate mofetil and iron ion preparations were administered concomitantly, a remarkable decrease of mycophenolate mofetil absorption was observed. Therefore it seems to be dear that we must avoid the concomitant administration of mycophenolate mofetil and iron ion preparations.