Humanized IgG1 monoclonal antibody (biosimilar to ocrelizumab) that binds CD20 on pre-B to mature B lymphocytes and depletes them via antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity, with induction of apoptosis; plasma cells (CD20-negative) are spared. This B-cell depletion reduces antigen presentation, costimulation, and proinflammatory cytokines, modulating CNS autoimmunity in multiple sclerosis.