Speed of onset of a new chewable formulation of oclacitinib maleate (Apoquel®) in a canine model of IL‐31‐induced pruritus

Abstract Oclacitinib maleate (Apoquel®, Zoetis Inc.) is commonly used around the world for the control/treatment of pruritus associated with allergic dermatitis and the control/treatment of atopic dermatitis in dogs at least 12 months of age. A new flavored chewable formulation of oclacitinib has been developed where more than 90% of doses offered to dogs were freely accepted when tested in clinical trials. The objective of this study was to determine whether the new chewable formulation of oclacitinib has a similar onset of anti‐pruritic activity as the original oclacitinib film‐coated tablets (FCT). Twenty‐one laboratory beagle dogs were randomized to treatment and received placebo, 0.4–0.6 mg/kg oclacitinib FCT or 0.4–0.6 mg/kg flavored chewable oclacitinib tablet ( n = 7/group). Efficacy was measured by assessing reduction in pruritus 1–3 h post‐administration of treatments. Pruritus was induced by injecting canine IL‐31, intravenously (2.5 μg/kg), approximately 15 min prior to the pruritus observation window. Results from this study demonstrated both oclacitinib FCT and the flavored chewable oclacitinib tablet significantly reduced IL‐31‐induced pruritus within 1–3 h post‐dosing compared to placebo ( p = .0069 and .0113, respectively), suggesting the new formulation of oclacitinib chewable tablets works as quickly to reduce pruritus in dogs as the oclacitinib FCT.