A Retrospective Case Series Reporting the Clinical Efficacy and Adverse Events of Oclacitinib Administration for Skin Disease in 238 Cats.

BACKGROUND

Off-label oclacitinib use for feline dermatoses management is increasing despite the paucity of data regarding optimal dose and adverse events (AEs).

OBJECTIVE

Review AEs, clinical efficacy, and dose regimens in cats prescribed oclacitinib.

MATERIALS AND

METHODS

Retrospective case series of 238 privately owned cats prescribed oclacitinib for dermatological disease. Signalment, history, laboratory abnormalities, oclacitinib dosage (mg/kg/day), treatment duration and AEs using a modified Naranjo Adverse Drug Reaction Probability Scale were retrieved from medical records spanning August 2014 to May 2024. Clinical efficacy was estimated using a pruritus Visual Analogue Scale and medical record lesional descriptions; categorised as complete, partial or no response.

RESULTS

The mean (x̄) initial dosage prescribed was 1.89 mg/kg/day. Monotherapy controlled clinical signs in 140 of 238 cats (59%), including 83 of 140 cats (59%) on twice daily (x̄ = 1.85 mg/kg/day) and 57 of 140 cats (41%) on once daily administration (x̄ = 1.05 mg/kg/day). The median treatment duration was 271.5 days (range 1 day-7.5 years). Main diagnoses successfully managed included feline atopic skin syndrome (61%) and pemphigus foliaceus (29%). Thirty-three 'definite' or 'probable' AEs were observed in 32 of 238 cats including: neutropaenia 6.3% (n = 15), gastrointestinal 4% (n = 9), lethargy 1.7% (n = 4), infection 0.8% (n = 2), hyperactivity 0.4% (n = 1), elevated alanine transaminase 0.4% (n = 1) and elevated creatinine 0.4% (n = 1).

CONCLUSIONS AND CLINICAL RELEVANCE: Off-label oclacitinib administration in cats appeared to be well-tolerated and effective with AEs typically mild, responsive to dose reduction, and similar to those reported in dogs.