This is a humanized IgG2 monoclonal antibody using the same sequences as the therapeutic antibody satralizumab. It specifically binds to both soluble and membrane-bound interleukin-6 (IL6) receptors, effectively inhibiting the signaling cascade and subsequent pro-inflammatory effects associated with endogenous IL6 binding. Satralizumab is indicated for the treatment of neuromyelitis optica spectrum disorder (NMOSD), a rare autoimmune inflammatory disorder affecting the central nervous system (CNS) characterized by demyelinating lesions in the optic nerve, spinal cord, brainstem, and cerebrum. It possesses a uniquely formulation of “recycling antibody technology”, enabling pH-dependent association with IL6 receptors. This mechanism allows satralizumab to bind an IL6 receptor until it reaches an endosome, where dissociation from the receptor occurs before re-entering plasma for further action. This innovative approach significantly prolongs the duration of action, by allowing single drug molecules to interact with multiple endogenous IL6 receptors prior to elimination.