Myfortic

Dosage Forms And Strengths

Myfortic is available as 360 mg and 180 mg tablets.

Table 1: Description of Myfortic (mycophenolic acid) Delayed-Release Tablets

Storage And Handling

360 mg tablet: Pale orange-red film-coated ovaloid tablet with imprint (debossing) “CT” on one side, containing 360 mg mycophenolic acid (MPA) as mycophenolate sodium.

Bottles of 120.................NDC 0078-0386-66

180 mg tablet: Lime green film-coated round tablet with bevelled edges and the imprint (debossing) “C” on one side, containing 180 mg mycophenolic acid (MPA) as mycophenolate sodium.

Bottles of 120.................NDC 0078-0385-66

Storage

Store at 25°C (77°F); excursions permitted to 15-30°C (59-86°F). Protect from moisture. Dispense in a tight container (USP).

Handling

Keep out of reach and sight of children. Myfortic tablets should not be crushed or cut in order to maintain the integrity of the enteric coating.

Teratogenic effects have been observed with mycophenolate sodium. If for any reason, the Myfortic tablets must be crushed, avoid inhalation of the powder, or direct contact of the powder, with skin or mucous membranes.

Distributed by: Novartis Pharmaceuticals Corporation, East Hanover, New Jersey 07936. Revised: Apr 2016

Prophylaxis Of Organ Rejection In Kidney Transplant

Myfortic® (mycophenolic acid) is indicated for the prophylaxis of organ rejection in adult patients receiving a kidney transplant.

Myfortic is indicated for the prophylaxis of organ rejection in pediatric patients 5 years of age and older who are at least 6 months post kidney transplant.

Myfortic is to be used in combination with cyclosporine and corticosteroids.

Limitations Of Use

Myfortic delayed-release tablets and mycophenolate mofetil (MMF) tablets and capsules should not be used interchangeably without physician supervision because the rate of absorption following the administration of these two products is not equivalent.

Dosage In Adult Kidney Transplant Patients

The recommended dose of Myfortic is 720 mg administered twice daily (1440 mg total daily dose).

Dosage In Pediatric Kidney Transplant Patients

The recommended dose of Myfortic in conversion (at least 6 months post-transplant) pediatric patients age 5 years and older is 400 mg/m² body surface area (BSA) administered twice daily (up to a maximum dose of 720 mg administered twice daily).

Administration

Myfortic tablets should be taken on an empty stomach, 1 hour before or 2 hours after food intake.

Myfortic tablets should not be crushed, chewed, or cut prior to ingesting. The tablets should be swallowed whole in order to maintain the integrity of the enteric coating.

Pediatric patients with a BSA of 1.19 to 1.58 m² may be dosed either with three Myfortic 180 mg tablets, or one 180 mg tablet plus one 360 mg tablet twice daily (1080 mg daily dose). Patients with a BSA of > 1.58 m² may be dosed either with four Myfortic 180 mg tablets, or two Myfortic 360 mg tablets twice daily (1440 mg daily dose). Pediatric doses for patients with BSA < 1.19 m² cannot be accurately administered using currently available formulations of Myfortic tablets.

Hypersensitivity Reactions

Myfortic is contraindicated in patients with a hypersensitivity to mycophenolate sodium, mycophenolic acid, mycophenolate mofetil, or to any of its excipients. Reactions like rash, pruritus, hypotension, and chest pain have been observed in clinical trials and post marketing reports.

WARNINGS

Included as part of the PRECAUTIONS section.

PRECAUTIONS

Embryofetal Toxicity

Use of Myfortic during pregnancy is associated with an increased risk of first trimester pregnancy loss and an increased risk of congenital malformations, especially external ear and other facial abnormalities including cleft lip and palate, and anomalies of the distal limbs, heart, esophagus, kidney, and nervous system.

Pregnancy Exposure Prevention And Planning

Females of reproductive potential must be aware of the increased risk of first trimester pregnancy loss and congenital malformations and must be counseled regarding pregnancy prevention and planning. For recommended pregnancy testing and contraception methods.

Management Of Immunosuppression

Only physicians experienced in immunosuppressive therapy and management of organ transplant patients should prescribe Myfortic. Patients receiving the drug should be managed in facilities equipped and staffed with adequate laboratory and supportive medical resources. The physicians responsible for maintenance therapy should have complete information requisite for the follow-up of the patient.

Lymphoma And Other Malignancies

Patients receiving immunosuppressants, including Myfortic, are at increased risk of developing lymphomas and other malignancies, particularly of the skin. The risk appears to be related to the intensity and duration of immunosuppression rather than to the use of any specific agent.

As usual for patients with increased risk for skin cancer, exposure to sunlight and UV light should be limited by wearing protective clothing and using a sunscreen with a high protection factor.

Post-transplant lymphoproliferative disorder (PTLD) has been reported in immunosuppressed organ transplant recipients. The majority of PTLD events appear related to Epstein Barr Virus (EBV) infection. The risk of PTLD appears greatest in those individuals who are EBV seronegative, a population which includes many young children.

Serious Infections

Patients receiving immunosuppressants, including Myfortic, are at increased risk of developing bacterial, viral, fungal, and protozoal infections, and new or reactivated viral infections including opportunistic infections. These infections may lead to serious, including fatal outcomes. Because of the danger of oversuppression of the immune system which can increase susceptibility to infection, combination immunosuppressant therapy should be used with caution.

New Or Reactivated Viral Infections

Polyomavirus associated nephropathy (PVAN), JC virus associated progressive multifocal leukoencephalopathy (PML), cytomegalovirus (CMV) infections, reactivation of hepatitis B (HBV) or hepatitis C (HCV) have been reported in patients treated with immunosuppressants, including the mycophenolic acid (MPA) derivatives Myfortic and MMF. Reduction in immunosuppression should be considered for patients who develop evidence of new or reactivated viral infections. Physicians should also consider the risk that reduced immunosuppression represents to the functioning allograft.

PVAN, especially due to BK virus infection, is associated with serious outcomes, including deteriorating renal function and renal graft loss. Patient monitoring may help detect patients at risk for PVAN.

PML, which is sometimes fatal, commonly presents with hemiparesis, apathy, confusion, cognitive deficiencies, and ataxia. Risk factors for PML include treatment with immunosuppressant therapies and impairment of immune function. In immunosuppressed patients, physicians should consider PML in the differential diagnosis in patients reporting neurological symptoms and consultation with a neurologist should be considered as clinically indicated.

The risk of CMV viremia and CMV disease is highest among transplant recipients seronegative for CMV at time of transplant who receive a graft from a CMV seropositive donor. Therapeutic approaches to limiting CMV disease exist and should be routinely provided. Patient monitoring may help detect patients at risk for CMV disease..

Viral reactivation has been reported in patients infected with HBV or HCV. Monitoring infected patients for clinical and laboratory signs of active HBV or HCV infection is recommended.

Blood Dyscrasias Including Pure Red Cell Aplasia

Cases of pure red cell aplasia (PRCA) have been reported in patients treated with MPA derivatives in combination with other immunosuppressive agents. The mechanism for MPA derivatives induced PRCA is unknown; the relative contribution of other immunosuppressants and their combinations in an immunosuppressive regimen is also unknown. In some cases PRCA was found to be reversible with dose reduction or cessation of therapy with MPA derivatives. In transplant patients, however, reduced immunosuppression may place the graft at risk. Changes to Myfortic therapy should only be undertaken under appropriate supervision in transplant recipients in order to minimize the risk of graft rejection.

Patients receiving Myfortic should be monitored for blood dyscrasias (e.g., neutropenia or anemia). The development of neutropenia may be related to Myfortic itself, concomitant medications, viral infections, or some combination of these reactions. Complete blood count should be performed weekly during the first month, twice monthly for the second and the third month of treatment, then monthly through the first year. If blood dyscrasias occur [neutropenia develops (ANC < 1.3 x 10³/mcL) or anemia], dosing with Myfortic should be interrupted or the dose reduced, appropriate tests performed, and the patient managed accordingly.

Serious GI Tract Complications

Gastrointestinal bleeding (requiring hospitalization), intestinal perforations, gastric ulcers, and duodenal ulcers have been reported in patients treated with Myfortic. Myfortic should be administered with caution in patients with active serious digestive system disease.

Immunizations

The use of live attenuated vaccines should be avoided during treatment with Myfortic; examples include (but not limited to) the following: intranasal influenza, measles, mumps, rubella, oral polio, BCG, yellow fever, varicella, and TY21a typhoid vaccines.

Rare Hereditary Deficiencies

Myfortic is an inosine monophosphate dehydrogenase inhibitor (IMPDH Inhibitor). Myfortic should be avoided in patients with rare hereditary deficiency of hypoxanthine-guanine phosphoribosyl-transferase (HGPRT) such as Lesch-Nyhan and Kelley-Seegmiller syndromes because it may cause an exacerbation of disease symptoms characterized by the overproduction and accumulation of uric acid leading to symptoms associated with gout such as acute arthritis, tophi, nephrolithiasis or urolithiasis and renal disease including renal failure.

Patient Counseling Information

See FDA-approved patient labeling (Medication Guide)

Embryofetal Toxicity

• Inform pregnant women and females of reproductive potential that use of Myfortic in pregnancy is associated with an increased risk of first trimester pregnancy loss and an increased risk of congenital malformations.
• In the event of a positive pregnancy test, discuss the risks and benefits of Myfortic with the patient. Encourage her to enroll in the pregnancy registry. (1-800-617-8191)..

Pregnancy Exposure Prevention And Planning

• Discuss pregnancy testing, pregnancy prevention and planning with females of reproductive potential.
• Inform females of reproductive potential must use acceptable birth control during entire Myfortic therapy and for 6 weeks after stopping Myfortic, unless the patient chooses to avoid heterosexual sexual intercourse completely (abstinence).
• For patients who are considering pregnancy, discuss appropriate alternative immunosuppressants with less potential for embryofetal toxicity. Risks and benefits of Myfortic should be discussed with the patient .

Nursing Mothers

Advise patients that they should not breastfeed during Myfortic therapy.

Development Of Lymphoma And Other Malignancies

• Inform patients they are at increased risk of developing lymphomas and other malignancies, particularly of the skin, due to immunosuppression.
• Advise patients to limit exposure to sunlight and ultraviolet (UV) light by wearing protective clothing and use a sunscreen with a high protection factor.

Increased Risk Of Infection

Inform patients they are at increased risk of developing a variety of infections, including opportunistic infections, due to immunosuppression and to contact their physician if they develop any symptoms of infection.

Blood Dyscrasias

Inform patients they are at increased risk for developing blood dyscrasias (e.g., neutropenia or anemia) and to immediately contact their healthcare provider if they experience any evidence of infection, unexpected bruising, bleeding, or any other manifestation of bone marrow suppression.

Gastrointestinal Tract Complications

Inform patients that Myfortic can cause gastrointestinal tract complications including bleeding, intestinal perforations, and gastric or duodenal ulcers. Advise the patient to contact their healthcare provider if they have symptoms of gastrointestinal bleeding or sudden onset or persistent abdominal pain.

Immunizations

Inform patients that Myfortic can interfere with the usual response to immunizations and that they should avoid live vaccines.

Administration Instructions

Advise patients to swallow Myfortic tablets whole, and not crush, chew, or cut the tablets. Inform patients to take Myfortic on an empty stomach, 1 hour before or 2 hours after food intake.

Drug Interactions

Patients should be advised to report to their doctor the use of any other medications while taking Myfortic. The simultaneous administration of any of the following drugs with Myfortic may result in clinically significant adverse reactions:

Antacids with magnesium and aluminum hydroxides
Azathioprine
Cholestyramine
Hormonal Contraceptives (e.g., birth control pill, transdermal patch, vaginal ring, injection, and implant)

Nonclinical Toxicology

Carcinogenesis, Mutagenesis, Impairment Of Fertility

In a 104-week oral carcinogenicity study in rats, mycophenolate sodium was not tumorigenic at daily doses up to 9 mg per kg, the highest dose tested. This dose resulted in approximately 0.6 to 1.2 times the systemic exposure (based on plasma AUC) observed in renal transplant patients at the recommended dose of 1440 mg per day. Similar results were observed in a parallel study in rats performed with MMF. In a 104-week oral carcinogenicity study in mice, MMF was not tumorigenic at a daily dose level as high as 180 mg per kg (which corresponds to 0.6 times the recommended mycophenolate sodium therapeutic dose, based on body surface area).

The genotoxic potential of mycophenolate sodium was determined in five assays. Mycophenolate sodium was genotoxic in the mouse lymphoma/thymidine kinase assay, the micronucleus test in V79 Chinese hamster cells, and the in vivo mouse micronucleus assay. Mycophenolate sodium was not genotoxic in the bacterial mutation assay (Salmonella typhimurium TA 1535, 97a, 98, 100, and 102) or the chromosomal aberration assay in human lymphocytes.

Mycophenolate mofetil generated similar genotoxic activity. The genotoxic activity of mycophenolic acid (MPA) is probably due to the depletion of the nucleotide pool required for DNA synthesis as a result of the pharmacodynamic mode of action of MPA (inhibition of nucleotide synthesis).

Mycophenolate sodium had no effect on male rat fertility at daily oral doses as high as 18 mg per kg and exhibited no testicular or spermatogenic effects at daily oral doses of 20 mg per kg for 13 weeks (approximately 2 times the systemic exposure of MPA at the recommended therapeutic dose). No effects on female fertility were seen up to a daily dose of 20 mg per kg (approximately 3 times the systemic exposure of MPA at the recommended therapeutic dose).

Use In Specific Populations

Pregnancy

Pregnancy Category D

For those females using Myfortic at any time during pregnancy and those becoming pregnant within 6 weeks of discontinuing therapy, the healthcare practitioner should report the pregnancy to the Mycophenolate Pregnancy Registry (1-800-617-8191). The healthcare practitioner should strongly encourage the patient to enroll in the pregnancy registry. The information provided to the registry will help the Health Care Community to better understand the effects of mycophenolate in 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 congenital malformations, especially external ear and other facial abnormalities including cleft lip and palate, and anomalies of the distal limbs, heart, esophagus, kidney and nervous system. In animal studies, congenital malformations and pregnancy loss occurred when pregnant rats and rabbits received mycophenolic acid at dose multiples similar to and less than clinical doses.

Risks and benefits of Myfortic should be discussed with the patient. When appropriate, consider alternative immunosuppressants with less potential for embryofetal toxicity. In certain situations, the patient and her healthcare practitioner may decide that the maternal benefits outweigh the risks to the fetus. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to the fetus.

Data

Human Data

In the National Transplantation Pregnancy Registry (NTPR), there were data on 33 MMF-exposed pregnancies in 24 transplant patients; there were 15 spontaneous abortions (45%) and 18 live-born infants. Four of these 18 infants had structural malformations (22%). In postmarketing data (collected from 1995 to 2007) on 77 women exposed to systemic MMF during pregnancy, 25 had spontaneous abortions and 14 had a malformed infant or fetus. Six of 14 malformed offspring had ear abnormalities. Because these postmarketing data are reported voluntarily, it is not always possible to reliably estimate the frequency of particular adverse outcomes. These malformations are similar to findings in animal reproductive toxicology studies. For comparison, the background rate for congenital anomalies in the United States is about 3%, and NTPR data show a rate of 4%-5% among babies born to organ transplant patients using other immunosuppressive drugs. There are no relevant qualitative or quantitative differences in the teratogenic potential of mycophenolate sodium and MMF.

Animal Data

In a teratology study performed with mycophenolate sodium in rats, at a dose as low as 1 mg per kg, malformations in the offspring were observed, including anophthalmia, exencephaly, and umbilical hernia. The systemic exposure at this dose represents 0.05 times the clinical exposure at the dose of 1440 mg per day Myfortic. In teratology studies in rabbits, fetal resorptions and malformations occurred at doses equal to or greater than 80 mg per kg per day, in the absence of maternal toxicity (which corresponds to about 1.1 times the recommended clinical dose, based on body surface area).

Nursing Mothers

It is not known whether MPA is excreted in human milk. Because many drugs are excreted in human milk and because of the potential for serious adverse reactions in nursing infants from Myfortic, a decision should be made whether to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother.

Pediatric Use

The safety and effectiveness of Myfortic have been established in pediatric kidney transplant patients 5 to 16 years of age who were initiated on Myfortic at least 6 months post-transplant. Use of Myfortic in this age group is supported by evidence from adequate and well-controlled studies of Myfortic in a similar population of adult kidney transplant patients with additional pharmacokinetic data in pediatric kidney transplant patients . Pediatric doses for patients with BSA < 1.19 m² cannot be accurately administered using currently available formulations of Myfortic tablets.

The safety and effectiveness of Myfortic in de novo pediatric kidney transplant patients and in pediatric kidney transplant patients below the age of 5 years have not been established.

Geriatric Use

Clinical studies of Myfortic did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Of the 372 patients treated with Myfortic in the clinical trials, 6% (N=21) were 65 years of age and older and 0.3% (N=1) were 75 years of age and older. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. In general, dose selection for an elderly patient should be cautious, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

Females Of Reproductive Potential

Pregnancy Exposure Prevention And Planning

Females of reproductive potential must be made aware of the increased risk of first trimester pregnancy loss and congenital malformations and must be counseled regarding pregnancy prevention and planning.

Females of reproductive potential include girls who have entered puberty and all women who have a uterus and have not passed through menopause. Menopause is the permanent end of menstruation and fertility. Menopause should be clinically confirmed by a patient's healthcare practitioner. Some commonly used diagnostic criteria include 1) 12 months of spontaneous amenorrhea (not amenorrhea induced by a medical condition or medical therapy), or 2) postsurgical from a bilateral oophorectomy.

Pregnancy Testing

To prevent unplanned exposure during pregnancy, females of reproductive potential should have a serum or urine pregnancy test with a sensitivity of at least 25 mIU/mL immediately before starting Myfortic. Another pregnancy test with the same sensitivity should be done 8 to 10 days later. Repeat pregnancy tests should be performed during routine follow-up visits. Results of all pregnancy tests should be discussed with the patient.

In the event of a positive pregnancy test, females should be counseled with regard to whether the maternal benefits of mycophenolate treatment may outweigh the risks to the fetus in certain situations.

Contraception

Females of reproductive potential taking Myfortic must receive contraceptive counseling and use acceptable contraception (see Table 5 for Acceptable Contraception Methods). Patients must use acceptable birth control during entire Myfortic therapy, and for 6 weeks after stopping Myfortic, unless the patient chooses abstinence (she chooses to avoid heterosexual intercourse completely).

Patients should be aware that Myfortic reduces blood levels of the hormones in the oral contraceptive pill and could theoretically reduce its effectiveness.

Table 5: Acceptable Contraception Methods for Females of Reproductive Potential
Pick from the following birth control options:

Pregnancy Planning

For patients who are considering pregnancy, consider alternative immunosuppressants with less potential for embryofetal toxicity. Risks and benefits of Myfortic should be discussed with the patient.

Antacids with Magnesium and Aluminum Hydroxides

Absorption of a single dose of Myfortic was decreased when administered to 12 stable kidney transplant patients also taking magnesium-aluminum-containing antacids (30 mL): the mean Cmax and AUC(0-t) values for MPA were 25% and 37% lower, respectively, than when Myfortic was administered alone under fasting conditions.

Pantoprazole

In a trial conducted in 12 healthy volunteers, the pharmacokinetics of MPA were observed to be similar when a single dose of 720 mg of Myfortic was administered alone and following concomitant administration of Myfortic and pantoprazole, which was administered at a dose of 40 mg twice daily for 4 days.

The following drug interaction studies were conducted following the administration of MMF

Cholestyramine

Following single-dose oral administration of 1.5 grams MMF to 12 healthy volunteers pretreated with 4 grams three times daily of cholestyramine for 4 days, MPA AUC decreased approximately 40%. This decrease is consistent with interruption of enterohepatic recirculation which may be due to binding of recirculating MPAG with cholestyramine in the intestine.

Sevelamer

Concomitant administration of sevelamer and MMF in stable adult and pediatric kidney transplant patients decreased the mean MPA Cmax and AUC(0-12h) by 36% and 26% respectively.

Cyclosporine

Cyclosporine (Sandimmune®) pharmacokinetics (at doses of 275 to 415 mg/day) were unaffected by single and multiple doses of 1.5 grams twice daily of MMF in 10 stable kidney transplant patients. The mean (±SD) AUC (0-12h) and Cmax of cyclosporine after 14 days of multiple doses of MMF were 3290 (±822) ng•h/mL and 753 (±161) ng/mL, respectively, compared to 3245 (±1088) ng•h/mL and 700 (±246) ng/mL, respectively, 1 week before administration of MMF.

A total of 73 de novo kidney allograft recipients on MMF therapy received either low dose cyclosporine withdrawal by 6 months post-transplant (50 to 100 ng/mL for up to 3 months post-transplant followed by complete withdrawal at month 6 post-transplant) or standard dose cyclosporine (150 to 300 ng/mL from baseline through to month 4 post-transplant and 100 to 200 ng/mL thereafter). At month 12 post-transplant, the mean MPA (AUC(0-12h)) in the cyclosporine withdrawal group was approximately 40% higher, than that of the standard dose cyclosporine group.

Cyclosporine inhibits multidrug-resistance-associated protein 2 (MRP-2) transporter in the biliary tract, thereby preventing the excretion of MPAG into the bile that would lead to enterohepatic recirculation of MPA.

Norfloxacin and Metronidazole

Following single-dose administration of MMF (1 g) to 11 healthy volunteers on day 4 of a 5-day course of a combination of norfloxacin and metronidazole, the mean MPA AUC(0-48h) was reduced by 33% compared to the administration of MMF alone (p < 0.05). There was no significant effect on mean MPA AUC(0-48h) when MMF was concomitantly administered with norfloxacin or metronidazole separately. The mean (±SD) MPA AUC(0-48h) after coadministration of MMF with norfloxacin or metronidazole separately was 48.3 (±24) mcg•h/mL and 42.7 (±23) mcg•h/mL, respectively, compared with 56.2 (±24) mcg•h/mL after administration of MMF alone.

Rifampin

In a single heart-lung transplant patient on MMF therapy (1 gram twice daily), a 67% decrease in MPA exposure (AUC(0-12h)) was observed with concomitant administration of MMF and 600 mg rifampin daily.

In 8 kidney transplant patients on stable MMF therapy (1 gram twice daily), administration of 300 mg rifampin twice daily resulted in a 17.5% decrease in MPA AUC(0-12h) due to inhibition of enterohepatic recirculation of MPAG by rifampin. Rifampin coadministration also resulted in a 22.4% increase in MPAG AUC(0-12h).

Oral Contraceptives

In a drug-drug interaction trial, mean AUCs were similar for ethinyl estradiol and norethindrone, when coadministered with MMF as compared to administration of the oral contraceptives alone.

Acyclovir

Coadministration of MMF (1 gram) and acyclovir (800 mg) to 12 healthy volunteers resulted in no significant change in MPA AUC and Cmax. However, MPAG and acyclovir plasma mean AUC(0-24h) were increased 10% and 18%, respectively. Because MPAG plasma concentrations are increased in the presence of kidney impairment, as are acyclovir concentrations, the potential exists for mycophenolate and acyclovir or its prodrug (e.g., valacyclovir) to compete for tubular secretion, further increasing the concentrations of both drugs.

Ganciclovir

Following single-dose administration to 12 stable kidney transplant patients, no pharmacokinetic interaction was observed between MMF (1.5 grams) and intravenous ganciclovir (5 mg per kg). Mean (±SD) ganciclovir AUC and Cmax (n=10) were 54.3 (±19.0) mcg•h/mL and 11.5 (±1.8) mcg/mL, respectively, after coadministration of the two drugs, compared to 51.0 (±17.0) mcg•h/mL and 10.6 (±2.0) mcg/mL, respectively, after administration of intravenous ganciclovir alone. The mean (±SD) AUC and Cmax of MPA (n=12) after coadministration were 80.9 (±21.6) mcg•h/mL and 27.8 (±13.9) mcg/mL, respectively, compared to values of 80.3 (±16.4) mcg•h/mL and 30.9 (±11.2) mcg/mL, respectively, after administration of MMF alone.

Because MPAG plasma concentrations are increased in the presence of renal impairment, as are ganciclovir concentrations, the two drugs will compete for tubular secretion and thus further increases in concentrations of both drugs may occur. In patients with renal impairment in which MMF and ganciclovir or its prodrug (e.g., valganciclovir) are coadministered, patients should be monitored carefully.

Ciprofloxacin and Amoxicillin plus Clavulanic Acid

A total of 64 MMF treated kidney transplant recipients received either oral ciprofloxacin 500 mg twice daily or amoxicillin plus clavulanic acid 375 mg three times daily for 7 or at least 14 days. Approximately 50% reductions in median trough MPA concentrations (predose) from baseline (MMF alone) were observed in 3 days following commencement of oral ciprofloxacin or amoxicillin plus clavulanic acid. These reductions in trough MPA concentrations tended to diminish within 14 days of antibiotic therapy and ceased within 3 days after discontinuation of antibiotics. The postulated mechanism for this interaction is an antibiotic-induced reduction in glucuronidase-possessing enteric organisms leading to a decrease in enterohepatic recirculation of MPA. The change in trough level may not accurately represent changes in overall MPA exposure; therefore, clinical relevance of these observations is unclear.

Pregnancy Category D

For those females using Myfortic at any time during pregnancy and those becoming pregnant within 6 weeks of discontinuing therapy, the healthcare practitioner should report the pregnancy to the Mycophenolate Pregnancy Registry (1-800-617-8191). The healthcare practitioner should strongly encourage the patient to enroll in the pregnancy registry. The information provided to the registry will help the Health Care Community to better understand the effects of mycophenolate in 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 congenital malformations, especially external ear and other facial abnormalities including cleft lip and palate, and anomalies of the distal limbs, heart, esophagus, kidney and nervous system. In animal studies, congenital malformations and pregnancy loss occurred when pregnant rats and rabbits received mycophenolic acid at dose multiples similar to and less than clinical doses.

Risks and benefits of Myfortic should be discussed with the patient. When appropriate, consider alternative immunosuppressants with less potential for embryofetal toxicity. In certain situations, the patient and her healthcare practitioner may decide that the maternal benefits outweigh the risks to the fetus. If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to the fetus.

Data

Human Data

In the National Transplantation Pregnancy Registry (NTPR), there were data on 33 MMF-exposed pregnancies in 24 transplant patients; there were 15 spontaneous abortions (45%) and 18 live-born infants. Four of these 18 infants had structural malformations (22%). In postmarketing data (collected from 1995 to 2007) on 77 women exposed to systemic MMF during pregnancy, 25 had spontaneous abortions and 14 had a malformed infant or fetus. Six of 14 malformed offspring had ear abnormalities. Because these postmarketing data are reported voluntarily, it is not always possible to reliably estimate the frequency of particular adverse outcomes. These malformations are similar to findings in animal reproductive toxicology studies. For comparison, the background rate for congenital anomalies in the United States is about 3%, and NTPR data show a rate of 4%-5% among babies born to organ transplant patients using other immunosuppressive drugs. There are no relevant qualitative or quantitative differences in the teratogenic potential of mycophenolate sodium and MMF.

Animal Data

In a teratology study performed with mycophenolate sodium in rats, at a dose as low as 1 mg per kg, malformations in the offspring were observed, including anophthalmia, exencephaly, and umbilical hernia. The systemic exposure at this dose represents 0.05 times the clinical exposure at the dose of 1440 mg per day Myfortic. In teratology studies in rabbits, fetal resorptions and malformations occurred at doses equal to or greater than 80 mg per kg per day, in the absence of maternal toxicity (which corresponds to about 1.1 times the recommended clinical dose, based on body surface area).

The following adverse reactions are discussed in greater detail in other sections of the label.

• Embryofetal Toxicity
• Lymphomas and Other Malignancies
• Serious Infections
• New or Reactivated Viral Infections
• Blood Dyscrasias Including Pure Red Cell Aplasia
• Serious GI Tract Complications
• Rare Hereditary Deficiencies

Clinical Studies Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

The data described below derive from two randomized, comparative, active-controlled, double-blind, double-dummy trials in prevention of acute rejection in de novo and converted stable kidney transplant patients.

In the de novo trial, patients were administered either Myfortic 1.44 grams per day (N=213) or MMF 2 grams per day (N=210) within 48 hours post-transplant for 12 months in combination with cyclosporine, USP MODIFIED and corticosteroids. Forty-one percent of patients also received antibody therapy as induction treatment. In the conversion trial, renal transplant patients who were at least 6 months post-transplant and receiving 2 grams per day MMF in combination with cyclosporine USP MODIFIED, with or without corticosteroids for at least two weeks prior to entry in the trial were randomized to Myfortic 1.44 grams per day (N=159) or MMF 2 grams per day (N=163) for 12 months.

The average age of patients in both studies was 47 years and 48 years (de novo study and conversion study, respectively), ranging from 22 to 75 years. Approximately 66% of patients were male; 82% were white, 12% were black, and 6% other races. About 40% of patients were from the United States and 60% from other countries.

In the de novo trial, the overall incidence of discontinuation due to adverse reactions was 18% (39/213) and 17% (35/210) in the Myfortic and MMF arms, respectively. The most common adverse reactions leading to discontinuation in the Myfortic arm were graft loss (2%), diarrhea (2%), vomiting (1%), renal impairment (1%), CMV infection (1%), and leukopenia (1%). The overall incidence of patients reporting dose reduction at least once during the 0 to 12 month study period was 59% and 60% in the Myfortic and MMF arms, respectively. The most frequent reasons for dose reduction in the Myfortic arm were adverse reactions (44%), dose reductions according to protocol guidelines (17%), dosing errors (11%) and missing data (2%).

The most common adverse reactions ( ≥ 20%) associated with the administration of Myfortic were anemia, leukopenia, constipation, nausea, diarrhea, vomiting, dyspepsia, urinary tract infection, CMV infection, insomnia, and postoperative pain.

The adverse reactions reported in ≥ 10% of patients in the de novo trial are presented in Table 2 below.

Table 2: Adverse Reactions (%) Reported in ≥ 10% of de novo Kidney Transplant Patients in Either Treatment Group

Table 3 summarizes the incidence of opportunistic infections in de novo transplant patients.

Table 3: Viral and Fungal Infections (%) Reported Over 0 to 12 Months

Lymphoma developed in 2 de novo patients (1%), (1 diagnosed 9 days after treatment initiation) and in 2 conversion patients (1%) receiving Myfortic with other immunosuppressive agents in the 12-month controlled clinical trials.

Nonmelanoma skin carcinoma occurred in 1% de novo and 12% conversion patients. Other types of malignancy occurred in 1% de novo and 1% conversion patients.

The adverse reactions reported in < 10% of de novo or conversion patients treated with Myfortic in combination with cyclosporine and corticosteroids are listed in Table 4.

Table 4: Adverse Reactions Reported in < 10% of Patients Treated with Myfortic in Combination with Cyclosporine* and Corticosteroids

The following additional adverse reactions have been associated with the exposure to mycophenolic acid (MPA) when administered as a sodium salt or as mofetil ester:

Gastrointestinal: Intestinal perforation, gastrointestinal hemorrhage, gastric ulcers, duodenal ulcers , colitis (including CMV colitis), pancreatitis, esophagitis, and ileus.

Infections: Serious life-threatening infections such as meningitis and infectious endocarditis, tuberculosis, and atypical mycobacterial infection.

Respiratory: Interstitial lung disorders, including fatal pulmonary fibrosis.

Postmarketing Experience

The following adverse reactions have been identified during post-approval use of Myfortic or other MPA derivatives. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

• Congenital malformations including ear, facial, cardiac and nervous system malformations and an increased incidence of first trimester pregnancy loss have been reported following exposure to MMF during pregnancy .
• Infections
  • Cases of progressive multifocal leukoencephalopathy (PML), sometimes fatal.
  • Polyomavirus associated nephropathy (PVAN), especially due to BK virus infection, associated with serious outcomes, including deteriorating renal function and renal graft loss.
  • Viral reactivation in patients infected with HBV or HCV.
• Cases of pure red cell aplasia (PRCA) have been reported in patients treated with MPA derivatives in combination with other immunosuppressive agents.

The following additional adverse reactions have been identified during postapproval use of Myfortic: agranulocytosis, asthenia, osteomyelitis, lymphadenopathy, lymphopenia, wheezing, dry mouth, gastritis, peritonitis, anorexia, alopecia, pulmonary edema, Kaposi's sarcoma.

Signs And Symptoms

There have been anecdotal reports of deliberate or accidental overdoses with Myfortic, whereas not all patients experienced related adverse reactions.

In those overdose cases in which adverse reactions were reported, the reactions fall within the known safety profile of the class. Accordingly an overdose of Myfortic could possibly result in oversuppression of the immune system and may increase the susceptibility to infection including opportunistic infections, fatal infections and sepsis. If blood dyscrasias occur (e.g., neutropenia with absolute neutrophil count < 1.5 x 103/mcL or anemia), it may be appropriate to interrupt or discontinue Myfortic.

Possible signs and symptoms of acute overdose could include the following: hematological abnormalities such as leukopenia and neutropenia, and gastrointestinal symptoms such as abdominal pain, diarrhea, nausea and vomiting, and dyspepsia.

Treatment And Management

General supportive measures and symptomatic treatment should be followed in all cases of overdosage. Although dialysis may be used to remove the inactive metabolite mycophenolic acid glucuronide (MPAG), it would not be expected to remove clinically significant amounts of the active moiety, mycophenolic acid, due to the 98% plasma protein binding of mycophenolic acid. By interfering with enterohepatic circulation of mycophenolic acid, activated charcoal or bile sequestrates, such as cholestyramine, may reduce the systemic mycophenolic acid exposure.

Myfortic exhibits linear and dose-proportional pharmacokinetics over the dose-range (360 to 2160 mg) evaluated. The absolute bioavailability of Myfortic in stable renal transplant patients on cyclosporine was 72%. MPA is highly protein bound ( > 98% bound to albumin). The predominant metabolite of MPA is the phenolic glucuronide (MPAG) which is pharmacologically inactive. A minor metabolite AcMPAG which is an acyl glucuronide of MPAG is also formed and has pharmacological activity comparable to MPA. MPAG undergoes renal elimination. A fraction of MPAG also undergoes biliary excretion, followed by deconjugation by gut flora and subsequent reabsorption as MPA. The mean elimination half-lives of MPA and MPAG ranged between 8 and 16 hours, and 13 and 17 hours, respectively.

Absorption

In vitro studies demonstrated that the enteric-coated Myfortic tablet does not release MPA under acidic conditions (pH < 5) as in the stomach but is highly soluble in neutral pH conditions as in the intestine. Following Myfortic oral administration without food in several pharmacokinetic studies conducted in renal transplant patients, consistent with its enteric-coated formulation, the median delay (Tlag) in the rise of MPA concentration ranged between 0.25 and 1.25 hours and the median time to maximum concentration (Tmax) of MPA ranged between 1.5 and 2.75 hours. In comparison, following the administration of MMF, the median Tmax ranged between 0.5 and 1.0 hours. In stable renal transplant patients on cyclosporine, USP MODIFIED based immunosuppression, gastrointestinal absorption and absolute bioavailability of MPA following the administration of Myfortic delayed-release tablet was 93% and 72%, respectively. Myfortic pharmacokinetics is dose proportional over the dose range of 360 to 2160 mg.

Distribution

The mean (± SD) volume of distribution at steady state and elimination phase for MPA is 54 (± 25) L and 112 (± 48) L, respectively. MPA is highly protein bound to albumin, > 98%. The protein binding of mycophenolic acid glucuronide (MPAG) is 82%. The free MPA concentration may increase under conditions of decreased protein binding (uremia, hepatic failure, and hypoalbuminemia).

Metabolism

MPA is metabolized principally by glucuronyl transferase to glucuronidated metabolites. The phenolic glucuronide of MPA, mycophenolic acid glucuronide (MPAG), is the predominant metabolite of MPA and does not manifest pharmacological activity. The acyl glucuronide is a minor metabolite and has comparable pharmacological activity to MPA. In stable renal transplant patients on cyclosporine, USP MODIFIED based immunosuppression, approximately 28% of the oral Myfortic dose was converted to MPAG by presystemic metabolism. The AUC ratio of MPA:MPAG:acyl glucuronide is approximately 1:24:0.28 at steady state. The mean clearance of MPA was 140 (± 30) mL/min.

Elimination

The majority of MPA dose administered is eliminated in the urine primarily as MPAG ( > 60%) and approximately 3% as unchanged MPA following Myfortic administration to stable renal transplant patients. The mean renal clearance of MPAG was 15.5 (± 5.9) mL/min. MPAG is also secreted in the bile and available for deconjugation by gut flora. MPA resulting from the deconjugation may then be reabsorbed and produce a second peak of MPA approximately 6 to 8 hours after Myfortic dosing. The mean elimination half-life of MPA and MPAG ranged between 8 and 16 hours, and 13 and 17 hours, respectively.

Food Effect

Compared to the fasting state, administration of Myfortic 720 mg with a high-fat meal (55 g fat, 1000 calories) had no effect on the systemic exposure (AUC) of MPA. However, there was a 33% decrease in the maximal concentration (Cmax), a 3.5-hour delay in the Tlag (range, -6 to 18 hours), and 5.0-hour delay in the Tmax (range, -9 to 20 hours) of MPA. To avoid the variability in MPA absorption between doses, Myfortic should be taken on an empty stomach.