2017 ACVIM Forum Research Abstract Program

Concentration of MPA and its derivatives in plasma were determined using a validated chromatographic method. Non-compartmental analysis was done to estimate PK parameters of MPA. All cats bio-transformed MMF into MPA. Results suggest that cats bio-transformed MMF to MPA relatively fast, as observed in an intravenous PK experiment done in our laboratory. There was significant variation in the absorption phase of the concentration time profile of the drug as reflected in the dispersion of the Tmax values. In addition, there was significant inter-individual variability in MPA exposure. The shape of concentration vs. time profiles of MPA after the first dose of MMF suggests that MPA undergoes enterohepatic recycling. Following multiple administrations, the trough MPA levels do not reflect a significant accumulation of drug in plasma for the BID dosage regimens evaluated. There was a small accumulation over time of MPA after the TID administration of MMF. Three metabolites of MPA were detected in cats; phenol glucuronide, phenol glucoside and acyl glucuronide after the administration of 15 mg/kg. No acyl glucuronide metabolites were identified in the 10 mg/kg PO BID group.