Used primarily in the treatment of moderate to severe atopic dermatitis, especially in patients who do not respond well to topical therapies or immunosuppressants. It works by selectively inhibiting Janus kinase 1 (JAK1), which plays a key role in the signaling pathways of inflammatory cytokines involved in the disease. This inhibition helps reduce itching, inflammation, and skin lesions associated with atopic dermatitis. The drug is taken orally, offering a convenient option for long-term management. It is particularly beneficial for adults and adolescents with significant disease burden, improving quality of life and symptom control.