bezexitinib

Bezexitinib (BOS-475) is an orally bioavailable, selective small-molecule inhibitor of Janus kinase 1 (JAK1) currently under clinical development by Hangzhou Bangshun Pharmaceutical in collaboration with Huadong Medicine. By specifically targeting the JAK1 isoform, the drug modulates the JAK-STAT signaling pathway, thereby inhibiting the production and signaling of various pro-inflammatory cytokines such as IL-6 and IFN-γ. This selectivity is designed to provide therapeutic efficacy in autoimmune and inflammatory conditions while potentially minimizing off-target effects associated with the inhibition of other JAK family members, such as JAK2-mediated hematological toxicities. Bezexitinib is being evaluated in Phase 2 clinical trials for several indications, including rheumatoid arthritis, atopic dermatitis, alopecia areata, and ankylosing spondylitis.