Enspryng (satralizumab) is a monoclonal antibody designed to target and block the interleukin-6 (IL-6) receptor, a key driver of inflammation in neuromyelitis optica spectrum disorder (NMOSD). It is indicated for the treatment of adults with NMOSD who are anti-aquaporin-4 (AQP4) antibody positive. By inhibiting IL-6 signaling, Enspryng helps reduce relapses that can lead to serious disability, such as vision loss and paralysis. Administered as a subcutaneous injection every four weeks (after initial loading doses), Enspryng is the first NMOSD therapy that can be self-administered at home.