Used in the treatment of autoimmune diseases such as rheumatoid arthritis due to its role as a selective inhibitor of Janus kinase 1 (JAK1). It modulates inflammatory signaling pathways by reducing the activity of cytokines involved in immune responses. This compound has shown efficacy in reducing joint inflammation and slowing disease progression in clinical studies. It is also being investigated for use in other conditions involving dysregulated JAK-STAT signaling, including psoriasis and inflammatory bowel disease. Its selectivity for JAK1 over other JAK family members may offer a favorable safety profile with reduced off-target effects.