Mechanism of Action
An investigational monoclonal antibody that blocks the neonatal Fc receptor (FcRn), which normally recycles IgG antibodies and extends their half-life in the body. By blocking FcRn, nipocalimab selectively accelerates the clearance of pathogenic IgG autoantibodies — including the antinuclear antibodies characteristic of SLE — without broadly suppressing the rest of the immune system. Granted FDA Fast Track designation for SLE in March 2026, supported by Phase 2 data showing reduced disease activity and potential for reducing corticosteroid use.