FCGRT and myasthenia gravis: The FcRn blocker efgartigimod, a humanized IgG1-derived Fc fragment which competitively inhibits the FcRn, has recently been approved by the U.S. Food and Drug Administration for the treatment of anti-acetylcholine receptor antibody-positive myasthenia gravis, and is currently under investigation in CIDP (Table 1).