Mycophenolate

Antacids with Magnesium and Aluminum Hydroxides: Decreases concentrations of MPA; concomitant use is not recommended. ( 7.1 ) Azathioprine: Competition for purine metabolism; concomitant administration is not recommended. ( 7.2 ) Cholestyramine, Bile Acid Sequestrates, Oral Activated Charcoal, and Other Drugs that Interfere with Enterohepatic Recirculation: May decrease MPA concentrations; concomitant use is not recommended. ( 7.3 ) Sevelamer: May decrease MPA concentrations; concomitant use is not recommended. ( 7.4 ) Cyclosporine: May decrease MPA concentrations; exercise caution when switching from cyclosporine to other drugs or from other drugs to cyclosporine.

( 7.5 ) Norfloxacin and Metronidazole: May decrease MPA concentrations; concomitant use with both drugs is not recommended. ( 7.6 ) Rifampin: May decrease MPA concentrations; concomitant use is not recommended unless the benefit outweighs the risk. ( 7.7 ) Hormonal Contraceptives: May reduce the effectiveness of oral contraceptives. Additional barrier contraceptive methods must be used. ( 5.2 , 7.8 ) Acyclovir, Valacyclovir, Ganciclovir, Valganciclovir, and Other Drugs that Undergo Renal Tubular Secretion: May increase concentrations of mycophenolic acid glucuronide (MPAG) and coadministered drug; monitor blood cell counts. ( 7.9 )

7.1 Antacids With Magnesium and Aluminum Hydroxides Concomitant use of Myfortic and antacids decreased plasma concentrations of mycophenolic acid (MPA). It is recommended that Myfortic and antacids not be administered simultaneously [see Clinical Pharmacology (12.3)] .

7.2 Azathioprine Given that azathioprine and MMF inhibit purine metabolism, it is recommended that Myfortic not be administered concomitantly with azathioprine or MMF.

7.3 Cholestyramine, Bile Acid Sequestrates, Oral Activated Charcoal and Other Drugs That Interfere With Enterohepatic Recirculation Drugs that interrupt enterohepatic recirculation may decrease MPA plasma concentrations when coadministered with MMF. Therefore, do not administer Myfortic with cholestyramine or other agents that may interfere with enterohepatic recirculation or drugs that may bind bile acids, e.g., bile acid sequestrates or oral activated charcoal, because of the potential to reduce the efficacy of Myfortic [see Clinical Pharmacology (12.3)] .

7.4 Sevelamer Concomitant administration of sevelamer and MMF may decrease MPA plasma concentrations. Sevelamer and other calcium-free phosphate binders should not be administered simultaneously with Myfortic [see Clinical Pharmacology (12.3)] .

7.5 Cyclosporine Cyclosporine inhibits the enterohepatic recirculation of MPA, and therefore, MPA plasma concentrations may be decreased when Myfortic is coadministered with cyclosporine. Clinicians should be aware that there is also a potential change of MPA plasma concentrations after switching from cyclosporine to other immunosuppressive drugs or from other immunosuppressive drugs to cyclosporine in patients concomitantly receiving Myfortic [see Clinical Pharmacology (12.3)] .

7.6 Norfloxacin and Metronidazole MPA plasma concentrations may be decreased when MMF is administrated with norfloxacin and metronidazole. Therefore, Myfortic is not recommended to be given with the combination of norfloxacin and metronidazole. Although there will be no effect on MPA plasma concentrations when Myfortic is concomitantly administered with norfloxacin or metronidazole when given separately [see Clinical Pharmacology (12.3)] .

7.7 Rifampin The concomitant administration of MMF and rifampin may decrease MPA plasma concentrations. Therefore, Myfortic is not recommended to be given with rifampin concomitantly unless the benefit outweighs the risk [see Clinical Pharmacology (12.3)] .

7.8 Hormonal Contraceptives In a drug interaction study, mean levonorgestrel AUC was decreased by 15% when coadministered with MMF. Although Myfortic may not have any influence on the ovulation-suppressing action of oral contraceptives, additional barrier contraceptive methods must be used when Myfortic is coadministered with hormonal contraceptives (e.g., birth control pill, transdermal patch, vaginal ring, injection, and implant) [see Warnings and Precautions (5.1), Use in Specific Populations (8.3), Clinical Pharmacology (12.3)] .

7.9 Acyclovir (Valacyclovir), Ganciclovir (Valganciclovir), and Other Drugs That Undergo Renal Tubular Secretion The coadministration of MMF and acyclovir or ganciclovir may increase plasma concentrations of mycophenolic acid glucuronide (MPAG) and acyclovir/valacyclovir/ganciclovir/valganciclovir as their coexistence competes for tubular secretion. Both acyclovir/valacyclovir/ganciclovir/valganciclovir and MPAG concentrations will be also increased in the presence of renal impairment. Acyclovir/valacyclovir/ganciclovir/valganciclovir may be taken with Myfortic; however, during the period of treatment, physicians should monitor blood cell counts [see Clinical Pharmacology (12.3)] .

7.10 Ciprofloxacin, Amoxicillin Plus Clavulanic Acid and Other Drugs That Alter the Gastrointestinal Flora Drugs that alter the gastrointestinal flora, such as ciprofloxacin or amoxicillin plus clavulanic acid may interact with MMF by disrupting enterohepatic recirculation. Interference of MPAG hydrolysis may lead to less MPA available for absorption when Myfortic is concomitantly administered with ciprofloxacin or amoxicillin plus clavulanic acid. The clinical relevance of this interaction is unclear; however, no dose adjustment of Myfortic is needed when coadministered with these drugs [see Clinical Pharmacology (12.3)] .

7.11 Pantoprazole Administration of pantoprazole at a dose of 40 mg twice daily for 4 days to healthy volunteers did not alter the pharmacokinetics of a single dose of Myfortic [see Clinical Pharmacology (12.3)] .

8.1 Pregnancy Risk Summary Following oral or intravenous (IV) administration, MMF is metabolized to mycophenolic acid (MPA), the active ingredient in Myfortic and the active form of the drug. Use of MMF during pregnancy is associated with an increased risk of first trimester pregnancy loss and an increased risk of multiple congenital malformations in multiple organ systems (see Human Data) .

Oral administration of mycophenolate to rats and rabbits during the period of organogenesis produced congenital malformations and pregnancy loss at doses less than the recommended clinical dose (0.05 and 1.1 times exposure at the recommended clinical doses in kidney transplant patients for rats and rabbits, respectively) (see Animal Data) . Risks and benefits of Myfortic should be discussed with the patient. When appropriate, consider alternative immunosuppressants with less potential for embryo-fetal toxicity. The estimated background risk of pregnancy loss and congenital malformations in organ transplant populations is not clear. In the U.S.

general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively. Data Human Data A spectrum of congenital malformations (including multiple malformations in individual newborns) has been reported in 23% to 27% of live births in MMF exposed pregnancies, based on published data from pregnancy registries. Malformations that have been documented include external ear, eye, and other facial abnormalities, including cleft lip and palate, and anomalies of the distal limbs, heart, esophagus, kidney, and nervous system.

Based on published data from pregnancy registries, the risk of first trimester pregnancy loss has been reported at 45% to 49% following MMF exposure. Animal Data In animal reproductive toxicology studies, congenital malformations and pregnancy loss occurred when pregnant rats and rabbits received mycophenolate at dose multiples equivalent to and less than the recommended human dose. Oral administration of mycophenolate sodium to pregnant rats from Gestational Day 7 to Day 16 at a dose as low as 1 mg per kg resulted in malformations including anophthalmia, exencephaly, and umbilical hernia.

The systemic exposure at this dose represents 0.05 times the clinical exposure at the human dose of 1,440 mg per day of Myfortic. Oral administration of mycophenolate to pregnant rabbits from Gestational Day 7 to Day 19 resulted in embryofetal lethality and malformations, including ectopia cordis, ectopic kidneys, diaphragmatic…