Dr Ericka Wong discusses recent FDA approval of efgartigimod for myasthenia gravis.
Ericka Wong, MD: Efgartigimod, which is a neonatal Fc receptor inhibitor, has been approved for acetylcholine receptor antibody-positive generalized myasthenia gravis by the FDA in December of 2021. The neonatal Fc receptor is a protein that helps to maintain IgG [immunoglobulin G] levels by prolonging its half-life. By binding to the Fc region, the neonatal Fc receptor rescues IgG from lysosomal degradation. By blocking this receptor, efgartigimod prevents IgG recycling, and that leads to decreased circulating IgG levels. In the ADAPT trial, efgartigimod did have 20% of patients who were either MuSK [muscle-specific tyrosine kinase] or antibody negative, and there was suggestion that efgartigimod may be effective in these patients, although this does have to be further studied.
Trancsript Edited for Clarity