Mofecon-C 250/Mofecon 500 Mechanism of Action

Pharmacologic Category: Immunosuppressant Agent.
Pharmacology: Pharmacodynamics: Mechanism of action: Mycophenolic acid (MPA) exhibits a cytostatic effect on T and B lymphocytes. It is an inhibitor of inosine monophosphate dehydrogenase (IMPDH) which inhibits de novo guanosine nucleotide synthesis. T and B lymphocytes are dependent on this pathway for proliferation.
Pharmacokinetics: Onset of action: Peak effect: Correlation of toxicity or efficacy is still being developed. However, one study indicated that 12-hour Area under the curve (AUCs) > 40 mcg/mL/hour were correlated with efficacy and decreased episodes of rejection.
Absorption: Rapid and extensive: early post-transplant period mycophenolic acid (MPA) AUC values are lower (~45% to 53%) than later post-transplant period (> 3 months) MPA AUC values in both pediatric patients and adults.
Distribution: MPA: Oral: 4 L/kg.
Protein binding: MPA: > 97%, MPAG (inactive metabolite) 82%.
Metabolism: Hepatic and via GI tract; mycophenolate mofetil is completely hydrolyzed in the liver to mycophenolic acid (MPA: active metabolite): enterohepatic recirculation of MPA may occur. MPA is glucuronidated to MPAG (inactive metabolite).
Bioavailability: Oral: 80.7% to 94%: enterohepatic recirculation contributes to MPA concentration.
Half-life elimination: MPA: Oral: 18 hours.
Time to peak, plasma: Oral: MPA: 1 to 1.5 hours.
Excretion: MPA: Urine (<1%), feces (6%); MPAG: Urine (87%).
Special populations: Renal function impairment: mycophenolic acid AUC increased 75%, and mycophenolic acid glucuronide AUC increased 3- to 6-fold in patients with severe renal impairment (glomerular filtration rate [GFR] less than 25 mL/minute/1.73 m²). Hemodialysis usually does not remove mycophenolic acid or mycophenolic acid glucuronide.