NCT06127095 is an observational survey of RRMS patients receiving monoclonal antibody therapies under routine care: natalizumab (IV or SC), ocrelizumab, or ofatumumab. Drug types and mechanisms: natalizumab is an anti–α4-integrin (VLA‑4) monoclonal antibody that blocks leukocyte binding to VCAM‑1, inhibiting immune-cell adhesion and transmigration across the blood–brain barrier, thereby reducing CNS infiltration. Ocrelizumab is a humanized anti‑CD20 monoclonal antibody that depletes CD20+ B cells via ADCC/CDC/apoptosis. Ofatumumab is a fully human anti‑CD20 monoclonal antibody (SC) that similarly depletes B cells. Target cells/pathways: natalizumab targets α4-integrin–expressing lymphocytes (T cells, B cells, monocytes) and the VLA‑4/VCAM‑1 trafficking pathway, ocrelizumab/ofatumumab target CD20+ B cells (naïve/memory), impacting antigen presentation, cytokine signaling, and humoral priming. The study evaluates patient perspectives beyond clinical efficacy.