Hansoh’s Selective TYK2 Inhibitor HS‑10374 Hits Co‑Primary Endpoints in Pivotal Phase III Psoriasis Trial – Over Half of Patients Reach PASI 90 at Week 16

Hansoh Pharmaceutical Group Company Limited (HKG: 3692) announced that HS‑10374, its in‑house‑developed selective allosteric inhibitor of tyrosine kinase 2 (TYK2), met co‑primary endpoints and multiple secondary endpoints in the pivotal Phase III clinical trial for the treatment of adult moderate‑to‑severe plaque psoriasis.

Clinical Milestone

Clinical Evidence – Pivotal Phase III Trial

The pivotal Phase III study employed two co‑primary endpoints assessing improvement in skin lesions at Week 16: the proportion of patients achieving ≥75 % reduction in the Psoriasis Area and Severity Index from baseline (PASI 75), and the proportion achieving a static Physician Global Assessment score of 0 or 1 with at least a 2‑point improvement from baseline (sPGA 0/1) – both significantly superior to placebo. Secondary endpoints showed that more than half of HS‑10374‑treated patients achieved PASI 90 and close to one‑third reached PASI 100 by Week 16, indicating near‑complete to complete skin clearance in a large share of patients. Trial size, dosing regimen, and full safety data – not disclosed.

Drug Profile & Mechanism of Action

• Molecule: HS‑10374 – a TYK2 selective allosteric inhibitor, independently developed by Hansoh; positioned as a potential new oral treatment option for psoriasis patients.
• Target: The pseudokinase domain of TYK2 – the allosteric binding site that distinguishes it from traditional pan‑JAK inhibitors.
• Mechanism: Selectively blocks downstream signaling of key inflammatory cytokines including IL‑23 and IL‑12, with a theoretical advantage of reduced off‑target risk from inhibition of other JAK family kinases while controlling inflammation.
• Class Significance: TYK2, a member of the JAK kinase family, is a hot target in autoimmune disease – and selective allosteric TYK2 inhibition is regarded as an important direction in autoimmune drug development.

Market Impact & Outlook

• Psoriasis Disease Burden: Plaque psoriasis is a common chronic inflammatory autoimmune disease; moderate‑to‑severe patients suffer large lesion areas and recurrent symptoms with significant quality‑of‑life impact – sustaining strong demand for effective oral therapies.
• Competitive Positioning: With PASI 90 in >50 % and PASI 100 in ≈ one‑third of patients at Week 16, HS‑10374’s profile supports competitiveness in the oral psoriasis market; head‑to‑head comparisons versus marketed agents – not disclosed.
• Domestic Innovation Milestone: Reaching pivotal Phase III success marks a key R&D milestone for this homegrown TYK2 inhibitor, advancing China’s domestic pipeline in a class pioneered globally by allosteric TYK2 drugs.
• Pipeline Foundation: Beyond psoriasis, the TYK2 pathway is implicated in multiple autoimmune diseases – HS‑10374’s progress lays the foundation for Hansoh’s broader autoimmune pipeline expansion.
• Development Outlook: Hansoh will continue related research on HS‑10374, with ongoing evaluation of long‑term efficacy and safety; registration filing and launch timelines – not disclosed.

Forward‑Looking Statements
This brief contains forward‑looking statements regarding continued development, regulatory submission, long‑term efficacy and safety outcomes, and commercial expectations for HS‑10374. Phase III endpoint success does not guarantee regulatory approval. Actual results may differ due to risks including long‑term safety findings, regulatory review outcomes, competitive dynamics in the psoriasis and autoimmune markets, and reimbursement and pricing environment in China.-Fineline Info & Tech