Evaluation of Two Induction Protocols for Oclacitinib in Dogs.

BACKGROUND: Oclacitinib is approved for the treatment of canine atopic dermatitis (AD) and pruritus. The conventional administration protocol includes twice-daily oral dosing for 14 days with a subsequent reduction to once-daily administration. This reduction sometimes leads to an increase in pruritus. HYPOTHESIS/OBJECTIVES: The aim of this study was to compare the changes in skin lesions and pruritus following a shortened induction versus the conventional protocol for oclacitinib. ANIMALS: Forty-five client-owned dogs with AD were randomised into two groups. MATERIAL AND METHODS: The conventional protocol group (CP) received oclacitinib tablets at 0.4-0.6 mg/kg twice-daily for 14 days, then once-daily for 7 days. In the shortened induction protocol group (SIP), oclacitinib was administered twice-daily for 6 days, then once-daily for 15 days. Pruritus was assessed daily by the owners using a pruritus Visual Analog Scale (PVAS). Lesions were scored with the Canine Atopic Dermatitis Lesion Index (CADLI) at Day (D) 0 and D21. RESULTS: Data from 40 dogs were available. Mean CADLI scores decreased from 13.4 to 8 in the CP group (p = 0.12) and from 12.9 to 6.9 in the SIP group (p = 0.01), respectively. Mean pruritus scores decreased from 6.4 to 2.1 and from 5.7 to 1.9, respectively (p < 0.0001 each). No between-group differences were observed. An increase in pruritus following dose reduction was seen in two dogs (CP) and one dog (SIP). CONCLUSIONS AND CLINICAL RELEVANCE: The SIP was not significantly different to the CP with respect to improvement in lesion severity or pruritus.