HK Inno.N files for approval of Korea's only JAK-1 inhibitor drug for canine atopic dermatitis

HK Inno.N has entered the fast-growing global veterinary pharmaceutical market with a drug candidate built on its proprietary autoimmune-targeting technology — the first of its kind developed independently by a Korean company.

The company completed a Phase 3 clinical trial demonstrating superior itch relief and dosing convenience against a globally dominant competitor, moving the drug candidate into the commercialization phase in a market currently controlled by a single foreign product.

HK Inno.N said Monday it successfully completed a Phase 3 trial of IN-115314, an oral drug candidate for canine atopic dermatitis, and filed for product approval with the Animal and Plant Quarantine Agency.

IN-115314 is a small-molecule new drug in the Janus kinase-1 (JAK-1) inhibitor class — the only such compound held by a Korean company. It selectively blocks JAK-1 receptors involved in inflammatory signaling and itch transmission, a differentiated mechanism designed to maximize therapeutic efficacy while minimizing side effects.

The Phase 3 trial was conducted at 13 veterinary hospitals across South Korea, enrolling dogs diagnosed with atopic dermatitis. Researchers administered IN-115314 and a comparator drug — the existing global standard JAK inhibitor — over 28 days, measuring improvements in pruritus scores (PVAS) and skin lesion severity (CADESI).

IN-115314 demonstrated statistically significant superiority over the comparator drug with once-daily dosing, compared with the twice-daily regimen required by the reference treatment.

Average pruritus scores in the trial dogs fell from 7.46 before treatment to 2.12 at the four-week mark — a drop of more than half — while skin lesion scores declined from 33.80 to 16.18 over the same period.

The once-daily regimen showed a fast onset of action and sustained efficacy, which the company said should significantly improve convenience for owners managing dogs that require long-term care due to frequent relapses. Physiological indicators including heart rate and body temperature remained stable throughout, and no serious adverse events were observed.

The global market for canine atopic dermatitis treatments is currently valued at approximately $2.7 billion (about 4.058 trillion won) annually and is projected to expand to around $8.2 billion by 2034.

The market is currently dominated by Apoquel — an oclacitinib-based product made by Zoetis — which recorded global sales of approximately 1.7 trillion won in 2025. HK Inno.N aims to reshape the market with a domestically developed new drug by securing approval as quickly as possible.

In parallel with the veterinary approval process, HK Inno.N is pursuing a two-track development strategy using the same active compound for a human atopic dermatitis treatment in topical form. The human asset is currently in a domestic Phase 2 trial, and the company recently received Investigational New Drug (IND) approval from the U.S. Food and Drug Administration for a Phase 1b trial, laying the groundwork for entry into the global market.

"This Phase 3 trial confirmed that IN-115314 is a strong alternative capable of addressing unmet medical needs that existing veterinary treatments have failed to meet," a company official said. "We will pursue indication expansions into various areas utilizing the JAK inhibitor mechanism, including autoimmune skin diseases."