ATCvet code:
QD11AH92
Pharmacodynamics
Ilunocitinib is a non-selective Janus kinase (JAK) inhibitor. It inhibits the function of a variety of pruritogenic and pro-inflammatory cytokines, as well as cytokines involved in allergy which are dependent on JAK enzyme activity. Ilunocitinib has also been demonstrated to exert effects on the function of several cytokines involved in haematopoiesis and the innate immune response.
Pharmacokinetics
Ilunocitinib is rapidly and well absorbed after oral administration in dogs. After oral administration of the tablet at 0.8 mg/kg ilunocitinib in fed dogs, the absolute bioavailability was 80%, Cmax was 268 ng/mL, and AUCinf was 1330 h*ng/mL. The elimination half-life was 5.0 hours. In fasted dogs, oral bioavailability was 58% showing a similar elimination half-life as observed in fed dogs (5.4 hours), Cmax was 122 ng/mL, and AUCinf was 869 h*ng/mL. Time to peak plasma concentrations (Tmax) was between 1 to 4 hours.
After IV administration of 0.8 mg/kg, ilunocitinib had a low plasma clearance of 437 mL/h/kg. The volume of distribution was 1.58 L/kg and terminal half-life was 4.4 hours.
Ilunocitinib exhibits low and consistent protein binding with approximatively 50% bound in fortified dog plasma.
Ilunocitinib is metabolised in dogs to several metabolites. In both urine and faeces, the parent drug remains the predominant component, with a combination of di-hydroxylation and reduction processes giving rise to a few minor metabolites.
The route of elimination of ilunocitinib is balanced between the faecal and urinary routes.