Oclacitinib for canine atopic dermatitis — PROBABLE

In dogs with atopic dermatitis, does oclacitinib vs placebo reduce pruritus and skin lesions over the first weeks of treatment?

Shelf #270 · gate-verified and displayed under the developer's blinded-trial rule

PROBABLE: Oclacitinib controls the itch and lesions of canine atopic dermatitis, on one large, decisive randomised, double-blind, placebo-controlled trial — the single-trial basis of this shelf is stated on its face. In Cosgrove 2013 (299 client-owned dogs with chronic atopic dermatitis at 18 specialty clinics), owner-assessed pruritus scores fell from baseline by 66.7% at day 14 and 47.4% at day 28 on oclacitinib vs 3.9% and 10.4% on placebo, and clinician-assessed CADESI-02 lesion scores fell 48.4% at days 14 and 28 vs a 1.7% reduction and a 3.6% increase on placebo; differences were significant at all time points assessed (P < 0.0001). The clean placebo comparison ends at day 28 — after that, more than 86% of placebo dogs had moved to an open-label study — so the PROBABLE stamp covers the first month of control, which is what the trial actually randomised. Drafted Nov 10, 2026 (VetMed build, topic #270); all figures from abstracts fetched and verified at drafting.

Cosgrove 2013: oclacitinib cut pruritus scores by 66.7% at day 14 vs 3.9% on placebo (299 dogs, P < 0.0001)

Randomised, double-blind, placebo-controlled trial (between-group comparison clean to day 28; treatment to day 112)

Who: Dogs: client-owned dogs (n = 299) with a history of chronic atopic dermatitis, enrolled by clinicians at 18 specialty clinics in a randomized, double-blind, placebo-controlled trial — oclacitinib 0.4–0.6 mg/kg twice daily for 14 days, then once daily for up to 112 days, or an excipient-matched placebo. Owners assessed pruritus on a visual analog scale (VAS) on days 0, 1, 2, 7, 14, 28, 56, 84 and 112; clinicians assessed Canine AD Extent and Severity Index (CADESI-02) scores on days 0, 14, 28, 56, 84 and 112.

Result: On days 1, 2, 7, 14 and 28, oclacitinib-treated dogs had reductions from baseline in owner-assessed pruritus scores of 29.5%, 42.3%, 61.5%, 66.7% and 47.4%, compared with 6.5%, 9.1%, 6.5%, 3.9% and 10.4% reductions in placebo-treated dogs (these are percentage reductions in scores from baseline). On days 14 and 28, dermatologists recorded a 48.4% reduction in CADESI-02 scores in oclacitinib-treated dogs, compared with a 1.7% reduction and a 3.6% increase in placebo-treated dogs. Differences were significant at all time points assessed (P < 0.0001). The record concludes oclacitinib provided rapid, effective and safe control of atopic dermatitis.

Watch out: After day 28, more than 86% of placebo-treated dogs had moved to an open-label study, making later between-group comparisons biased — the record says so itself — so efficacy figures beyond day 28 are not placebo-controlled evidence. Pruritus is owner-assessed (subjective), though the clinician-assessed CADESI-02 lesions move the same way.

Cosgrove SB, Wren JA, Cleaver DM, Walsh KF, Follis SI, King VI, Tena JK, Stegemann MR. A blinded, randomized, placebo-controlled trial of the efficacy and safety of the Janus kinase inhibitor oclacitinib (Apoquel®) in client-owned dogs with atopic dermatitis. Vet Dermatol. 2013;24(6):587-97, e141-2. PMID: 24581322. Registry ID: none in the record. MeSH: Animals · Dermatitis, Atopic · Dermatologic Agents · Dog Diseases · Dogs · Female · Male · Pyrimidines · Sulfonamides

Synthesis: a single large blinded trial, decisive for the first month — and only the first month is placebo-controlled

Synthesis

Who: Synthesis of the card above: Cosgrove 2013 (randomised double-blind placebo-controlled trial, 299 dogs). This shelf rests on that one trial, as the VetMed single-trial exception allows.

Result: The trial is large for veterinary dermatology, double-blind with an excipient-matched placebo, and the separation is wide on both measures, each on its own timeline: owner itch scores separate from day 1 (reported on days 1, 2, 7, 14 and 28), and clinician lesion scores are reported as different at days 14 and 28 (CADESI-02 was assessed on days 0, 14, 28, 56, 84 and 112), with differences significant at all time points assessed (P < 0.0001) — that is what carries the PROBABLE stamp for short-term control of pruritus and lesions. It does not by itself answer long-term safety, use beyond 112 days, or how oclacitinib compares with other drugs; those are other shelves.

Watch out: Single-trial shelf: one manufacturer-programme trial, however large, is one trial. The day-56 to day-112 data are not placebo-controlled (placebo dogs crossed to open-label treatment), and this pack does not present them as such.

Synthesis of Cosgrove SB et al. PMID: 24581322. Registry ID as on the individual card.

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