Single Dose Pharmacokinetics of an FDA Approved Cannabidiol Medication in Healthy Cats

Abstract: Background – Cannabidiol (CBD) is emerging as a potential therapeutic agent in human and veterinary medicine for a myriad of conditions. The FDA has recently approved a CBD (Epidiolex®) in humans as add-on therapy for seizures, where oral absorption is increased in fed versus fasted states. Furthermore, recent evidence associated higher CBD levels with improved seizure control.

Hypothesis/Objective – Determination of a dose of Epidiolex® in healthy cats necessary to achieve anticipated antiseizure therapeutic concentrations, and to determine relative oral bioavailability of fasted versus fed animals. We hypothesized that oral bioavailability would be higher in fed cats.

Animals – 10 Healthy cats from a research colony.

Methods –On study day, each cat received 5mg/kg of CBD orally. Cats were randomized to be fed (n=5) or not fed (n=5) approximately 30minutes prior to oral dosing. Blood samples were collected serially once prior to and following administration for 48 hrs. Following a 1-month washout, the study was repeated by crossing cats to the alternate fed state.

Results – Mean maximum plasma concentration (C_max, ng/mL), time to maximum concentration (T_max, hours), disappearance half-life (hours), Area under the curve (ng*h/mL) and mean residence time (hours) for the fasted group were 269±333, 2.58±1.6, 6.3±3.6 hours, 921.5±1003, and 12.1±7.5 respectively, while for the fed group 465±220, 4.7±2.1, 6.9±2.9, 2650±1188, 10.2±2.4 respectively. Significant difference was limited to T_max. Relative bioavailability (F) after feeding compared to fasting was 2.9.

Conclusions: Epidiolex® administered orally appears to reach potentially therapeutic concentrations in healthy cats and oral bioavailability increases with feeding.