CellCept
CellCept - General Information
CellCept is the 2-morpholinoethyl ester of mycophenolic acid (MPA), an immunosuppressive agent, inosine monophosphate dehydrogenase (IMPDH) inhibitor.
Pharmacology of CellCept
CellCept is a prodrug of mycophenolic acid, an antibiotic substance derived from Penicillium stoloniferum. It blocks de novo biosynthesis of purine nucleotides by inhibition of the enzyme inosine monophosphate dehydrogenase. Mycophenolic acid is important because of its selective effects on the immune system. It prevents the proliferation of T-cells, lymphocytes, and the formation of antibodies from B-cells. It also may inhibit recruitment of leukocytes to inflammatory sites.
CellCept for patients
Patients should be informed of the need for repeated appropriate laboratory tests while they are receiving CellCept. Patients should be given complete dosage instructions and informed of the increased risk of lymphoproliferative disease and certain other malignancies. Women of childbearing potential should be instructed of the potential risks during pregnancy, and that they should use effective contraception before beginning CellCept therapy, during therapy, and for 6 weeks after CellCept has been stopped (see WARNINGS and PRECAUTIONS: Pregnancy).
CellCept Interactions
Drug interaction studies with mycophenolate mofetil have been conducted with acyclovir, antacids, cholestyramine, cyclosporine, ganciclovir, oral contraceptives, and trimethoprim/sulfamethoxazole. Drug interaction studies have not been conducted with other drugs that may be commonly administered to renal, cardiac or hepatic transplant patients. CellCept has not been administered concomitantly with azathioprine.
Acyclovir
Coadministration of mycophenolate mofetil (1 g) and acyclovir (800 mg) to 12 healthy volunteers resulted in no significant change in MPA AUC and Cmax. However, MPAG and acyclovir plasma AUCs were increased 10.6% and 21.9%, respectively. Because MPAG plasma concentrations are increased in the presence of renal impairment, as are acyclovir concentrations, the potential exists for mycophenolate and acyclovir or its prodrug (eg, valacyclovir) to compete for tubular secretion, further increasing the concentrations of both drugs.
Antacids With Magnesium and Aluminum Hydroxides
Absorption of a single dose of mycophenolate mofetil (2 g) was decreased when administered to ten rheumatoid arthritis patients also taking MaaloxÒ TC (10 mL qid). The Cmax and AUC(0-24h) for MPA were 33% and 17% lower, respectively, than when mycophenolate mofetil was administered alone under fasting conditions. CellCept may be administered to patients who are also taking antacids containing magnesium and aluminum hydroxides; however, it is recommended that CellCept and the antacid not be administered simultaneously.
Cholestyramine
Following single-dose administration of 1.5 g mycophenolate mofetil to 12 healthy volunteers pretreated with 4 g tid 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. Some degree of enterohepatic recirculation is also anticipated following intravenous administration of CellCept. Therefore, CellCept is not recommended to be given with cholestyramine or other agents that may interfere with enterohepatic recirculation.
Cyclosporine
Cyclosporine (SandimmuneÒ ) pharmacokinetics (at doses of 275 to 415 mg/day) were unaffected by single and multiple doses of 1.5 g bid of mycophenolate mofetil in 10 stable renal transplant patients. The mean (± SD) AUC(0-12h) and Cmax of cyclosporine after 14 days of multiple doses of mycophenolate mofetil 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 mycophenolate mofetil. The effect of cyclosporine on mycophenolate mofetil pharmacokinetics could not be evaluated in this study; however, plasma concentrations of MPA were similar to that for healthy volunteers.
Ganciclovir
Following single-dose administration to 12 stable renal transplant patients, no pharmacokinetic interaction was observed between mycophenolate mofetil (1.5 g) and intravenous ganciclovir (5 mg/kg). Mean (± SD) ganciclovir AUC and Cmax (n=10) were 54.3 (± 19.0) m g· h/mL and 11.5 (± 1.8) m g/mL, respectively, after coadministration of the two drugs, compared to 51.0 (± 17.0) m g· h/mL and 10.6 (± 2.0) m g/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) m g· h/mL and 27.8 (± 13.9) m g/mL, respectively, compared to values of 80.3 (± 16.4) m g· h/mL and 30.9 (± 11.2) m g/mL, respectively, after administration of mycophenolate mofetil 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 (eg, valganciclovir) are coadministered, patients should be monitored carefully.
Oral Contraceptives
A study of coadministration of CellCept (1 g bid) and combined oral contraceptives containing ethinylestradiol (0.02 mg to 0.04 mg) and levonorgestrel (0.05 mg to 0.20 mg), desogestrel (0.15 mg) or gestodene (0.05 mg to 0.10 mg) was conducted in 18 women with psoriasis over 3 consecutive menstrual cycles. Mean AUC(0-24h) was similar for ethinylestradiol and 3-keto desogestrel; however, mean levonorgestrel AUC(0-24h) significantly decreased by about 15%. There was large inter-patient variability (%CV in the range of 60% to 70%) in the data, especially for ethinylestradiol. Mean serum levels of LH, FSH and progesterone were not significantly affected. CellCept may not have any influence on the ovulation-suppressing action of the studied oral contraceptives. However, it is recommended that oral contraceptives are coadministered with CellCept with caution and additional birth control methods be considered.
Trimethoprim/sulfamethoxazole
Following single-dose administration of mycophenolate mofetil (1.5 g) to 12 healthy male volunteers on day 8 of a 10 day course of trimethoprim 160 mg/sulfamethoxazole 800 mg administered bid, no effect on the bioavailability of MPA was observed. The mean (± SD) AUC and Cmax of MPA after concomitant administration were 75.2 (± 19.8) m g· h/mL and 34.0 (± 6.6) m g/mL, respectively, compared to 79.2 (± 27.9) m g· h/mL and 34.2 (± 10.7) m g/mL, respectively, after administration of mycophenolate mofetil alone.
Other Interactions
The measured value for renal clearance of MPAG indicates removal occurs by renal tubular secretion as well as glomerular filtration. Consistent with this, coadministration of probenecid, a known inhibitor of tubular secretion, with mycophenolate mofetil in monkeys results in a 3-fold increase in plasma MPAG AUC and a 2-fold increase in plasma MPA AUC. Thus, other drugs known to undergo renal tubular secretion may compete with MPAG and thereby raise plasma concentrations of MPAG or the other drug undergoing tubular secretion.
Drugs that alter the gastrointestinal flora may interact with mycophenolate mofetil by disrupting enterohepatic recirculation. Interference of MPAG hydrolysis may lead to less MPA available for absorption.
Live Vaccines
During treatment with CellCept, the use of live attenuated vaccines should be avoided and patients should be advised that vaccinations may be less effective . Influenza vaccination may be of value. Prescribers should refer to national guidelines for influenza vaccination.
CellCept Contraindications
Allergic reactions to CellCept have been observed; therefore, CellCept is contraindicated in patients with a hypersensitivity to mycophenolate mofetil, mycophenolic acid or any component of the drug product. CellCept Intravenous is contraindicated in patients who are allergic to Polysorbate 80 (TWEEN).
Additional information about CellCept
CellCept Indication: For the prophylaxis of organ rejection in patients receiving allogeneic renal, cardiac or hepatic transplants. CellCept should be used concomitantly with cyclosporine and corticosteroids.
Mechanism Of Action: CellCept is hydrolyzed to form mycophenolic acid (MPA), which is the active metabolite. MPA is a potent, selective, uncompetitive, and reversible inhibitor of inosine monophosphate dehydrogenase (IMPDH), and therefore inhibits the de novo pathway of guanosine nucleotide synthesis without incorporation into DNA. Because T- and B-lymphocytes are critically dependent for their proliferation on de novo synthesis of purines, whereas other cell types can utilize salvage pathways, MPA has potent cytostatic effects on lymphocytes. MPA inhibits proliferative responses of T- and B-lymphocytes to both mitogenic and allospecific stimulation. Addition of guanosine or deoxyguanosine reverses the cytostatic effects of MPA on lymphocytes. MPA also suppresses antibody formation by B-lymphocytes. MPA prevents the glycosylation of lymphocyte and monocyte glycoproteins that are involved in intercellular adhesion to endothelial cells and may inhibit recruitment of leukocytes into sites of inflammation and graft rejection. CellCept did not inhibit early events in the activation of human peripheral blood mononuclear cells, such as the production of interleukin-1 (IL-1) and interleukin-2 (IL-2), but did block the coupling of these events to DNA synthesis and proliferation.
Drug Interactions: Iron Oral iron decreases the absorption of mycophenolate-mofetil
Rifampin Significant decreases in immunosuppressant levels
Tacrolimus Increased mycophenolic acid levels
Food Interactions: Take on empty stomach: 1 hour before or 2 hours after meals.
Do not take calcium, aluminium, magnesium or iron supplements within 2 hours of taking this medication.
Generic Name: Mycophenolate mofetil
Synonyms: Mycophenylate mofetil
Drug Category: Anti-Inflammatory Agents, Non-Steroidal; Antineoplastic Agents; Dermatologic Agents; Enzyme Inhibitors; Immunosuppressive Agents
Drug Type: Small Molecule; Approved; Investigational
Other Brand Names containing Mycophenolate mofetil: CellCept; Munoloc;
Absorption: Rapidly absorbed following oral administration. In 12 healthy volunteers, the mean absolute bioavailability of oral mycophenolate mofetil relative to intravenous mycophenolate mofetil (based on MPA AUC) was 94%. Food (27 g fat, 650 calories) has no effect on the extent of absorption (MPA AUC) of mycophenolate mofetil.
Toxicity (Overdose): Oral (LD50): Acute: 352 mg/kg [Rat], 1000 mg/kg [Mouse], and >6000 mg/kg [Rabbit]. 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.
Protein Binding: MPA (the active metabolite), at clinically relevant concentrations, is over 98% bound to plasma albumin.
Biotransformation: Following oral and intravenous dosing, mycophenolate mofetil undergoes complete metabolism to MPA, the active metabolite. Metabolism to MPA occurs presystemically after oral dosing. MPA is metabolized principally by glucuronyl transferase to form the phenolic glucuronide of MPA (MPAG) which is not pharmacologically active. In vivo, MPAG is converted to MPA via enterohepatic recirculation. The following metabolites of the 2-hydroxyethyl-morpholino moiety are also recovered in the urine following oral administration of mycophenolate mofetil to healthy subjects: N-(2-carboxymethyl)-morpholine, N-(2-hydroxyethyl)-morpholine, and the N-oxide of N-(2-hydroxyethyl)-morpholine.
Half Life: The mean elimination half-life for mycophenolic acid (the active metabolite) ranges from 8-16 hours, while that of the MPAG metabolite ranges from 13-17 hours.
Dosage Forms of CellCept: Powder, for solution Intravenous
Tablet Oral
Powder, for suspension Oral
Capsule Oral
Chemical IUPAC Name: 2-morpholin-4-ylethyl (E)-6-(4-hydroxy-6-methoxy-7-methyl-3-oxo-1H-2-benzofuran-5-yl)-4-methylhex-4-enoate
Chemical Formula: C23H31NO7
Mycophenolate mofetil on Wikipedia: https://en.wikipedia.org/wiki/Mycophenolate_mofetil
Organisms Affected: Humans and other mammals