Admin_Adham
The FDA has approved a label expansion for efgartigimod alfa (Vyvgart) and efgartigimod alfa/hyaluronidase (Vyvgart Hytrulo) to include adults with anti-acetylcholine receptor antibody (anti-AChR-Ab)-negative generalized myasthenia gravis (gMG), a population that has historically lacked effective treatment options.
The expanded indication makes efgartigimod — a neonatal Fc receptor antagonist — the first and only approved treatment for all serotypes of adults living with gMG, including anti-AChR-Ab positive, anti-MuSK-Ab positive, anti-LRP4-Ab positive, and triple seronegative, according to argenx.
About 20% of patients with gMG do not have detectable anti-AChR antibodies. These patients have often been excluded from clinical trials and face greater diagnostic uncertainty and unmet treatment needs.
The label expansion is based on results from the phase 3 ADAPT SERON trial, a randomized, double-blind, placebo-controlled study evaluating efgartigimod in patients with AChR-Ab-negative gMG across three serotypes.
As previously reported by Medscape Medical News, patients receiving efgartigimod achieved a significantly greater least squares mean improvement from baseline in Myasthenia Gravis Activities of Daily Living (MG-ADL) scores at 4 weeks than those receiving placebo (-3.35 vs -1.90; P = .007).
According to argenx, patients treated with efgartigimod experienced rapid, significant, and sustained improvements in symptoms related to functions such as speech, vision, swallowing, and physical function.
Improvements in MG-ADL and Quantitative Myasthenia Gravis scores were observed across subsequent treatment cycles across all serotypes. The therapy was generally well tolerated, with no new safety signals reported.
Full prescribing information for intravenous Vyvgart and subcutaneous Vyvgart Hytrulo is available online.
