Vanda Pharmaceuticals said Japan’s Ministry of Health, Labour and Welfare has granted orphan drug designation to imsidolimab, a high‑affinity humanized IgG4 monoclonal antibody, for the treatment of generalized pustular psoriasis (GPP). Imsidolimab targets interleukin‑36 (IL‑36) receptor signaling, addressing a deficiency in the endogenous IL‑36 receptor antagonist that is commonly seen in patients with GPP.
Orphan drug status in Japan is reserved for medicines intended to treat rare diseases with significant unmet medical need. About 2,200 people in Japan have been diagnosed with GPP, and IL36RN genetic variants linked to dysregulation of the IL‑36 pathway are enriched in the Japanese population, including well‑characterized founder families in Hokkaido.
With this designation, imsidolimab becomes eligible for development incentives in Japan, including subsidies for research and development costs and the potential for up to 10 years of market exclusivity after approval. Vanda noted that the Japanese orphan designation follows similar regulatory recognition in the United States and reflects broader global interest in imsidolimab’s potential.
The company highlighted that GPP is a rare and severe inflammatory skin disease associated with systemic complications and increased mortality, and said the new status underscores the significant unmet medical needs of patients living with the condition.
Subscribe to our e-Newsletters
Stay up to date with the latest news, articles, and events. Plus, get special offers
from American Pharmaceutical Review – all delivered right to your inbox!
Sign up now!