Jeff Guptill, MD, Neuromuscular Clinical Development Lead at Argenx, discusses the impact of the Vyvgart (efgartigimod alfa) approval on the myasthenia gravis (MG) community to treat patients with anti-MuSK-Ab positive, anti-LRP4-Ab positive, and/or triple seronegative MG.
MG is a chronic autoimmune neuromuscular disease characterized by weakness of the skeletal muscles. Common symptoms include weakness of the muscles that control the eye and eyelid, facial expressions, chewing, talking, and swallowing. The condition results from a defect in the transmission of nerve impulses to muscles due to the presence of antibodies against the acetylcholine receptor. The exact reason this occurs is not known.
In May 2026, the US Food and Drug Administration (FDA) approved Vyvgart (efgartigimod alfa) and Vyvgart Hytrulo (efgartigimod alfa and hyaluronidase) for the treatment of adult patients who have anti-MuSK-Ab positive, anti-LRP4-Ab positive, and/or triple seronegative MG. The medication was previously approved to treat patients with anti-AChR-Ab positive gMG.
Efgartigimod alfa is a first-in-class human IgG1 antibody fragment that binds to the neonatal Fc receptor (FcRn), resulting in the reduction of circulating IgG autoantibodies. Vyvgart Hytrulo is a subcutaneous combination of efgartigimod alfa and recombinant human hyaluronidase PH20 (rHuPH20) that allows for subcutaneous injection delivery.
Until this approval, traditional therapy was limited to cholinesterase inhibitors, corticosteroids and immunosuppressants for these MG subpopulations. However, research has shown that these subpopulations react to treatments in different ways, highlighting the need for more treatment options and research aimed at these specific subgroups.
Dr. Guptill explains the importance of this approval, specifically for the triple seronegative patients who now have their first rigorously studied treatment with a favorable safety and efficacy profile.
For more information on this approval visit, https://checkrare.com/fda-expands-indication-of-vyvgart-efgartigimod-alfa-for-adults-with-seronegative-myasthenia-gravis/
To learn more about MG and other rare neurological disorders, visit https://checkrare.com/diseases/neurology-nervous-system-diseases/
