The FDA has expanded approval of argenx’s VYVGART and VYVGART Hytrulo to include all adult generalized myasthenia gravis patients, including anti-MuSK-Ab positive, anti-LRP4-Ab positive, and triple seronegative subtypes, based on positive Phase 3 ADAPT SERON data.
Written By: Nikita Jha, BPharm
Reviewed By: Pharmacally Editorial Team
The U.S. Food and Drug Administration (FDA) has approved a label expansion for argenx’s VYVGART® and VYVGART Hytrulo® to treat all adult patients with generalized myasthenia gravis (gMG), regardless of antibody status. The expanded indication includes patients who are anti‑AChR‑antibody (Ab) positive, anti‑MuSK‑Ab positive, anti‑LRP4‑Ab positive, and those who are triple seronegative.
The approval is based on data from the Phase 3 ADAPT SERON study (NCT06298552), which evaluated VYVGART in adults with anti‑AChR antibody–negative gMG across anti‑MuSK‑Ab–positive, anti‑LRP4‑Ab–positive, and triple seronegative subgroups. The study met its primary endpoint, showing a statistically significant improvement in Myasthenia Gravis Activities of Daily Living (MG‑ADL) total score versus placebo at week 4. Patients treated with VYVGART achieved a mean 3.35‑point improvement in MG‑ADL scores from baseline. Improvements in both MG‑ADL and Quantitative Myasthenia Gravis (QMG) scores were observed across treatment cycles and the serotypes studied.
VYVGART was well tolerated, with a safety profile consistent with that observed in previous studies in anti‑AChR antibody–positive gMG patients.
“Today’s approval means that all adult gMG patients, regardless of serotype, can now benefit from VYVGART’s rapid onset, sustained disease control, and favorable safety profile,” said Luc Truyen, M.D., Ph.D., Chief Medical Officer at argenx. “For clinicians, this simplifies treatment decisions, representing a major advancement in reaching as many patients living with gMG as possible.”
James F. Howard Jr., M.D., Professor of Neurology at the University of North Carolina at Chapel Hill School of Medicine, noted that patients without detectable AChR antibodies have historically been underrepresented in clinical trials despite a significant disease burden. He added that the expanded approval may enable clinicians to prescribe targeted treatment more readily based on clinical diagnosis rather than antibody subtype alone.
Allison Foss, Executive Director of the Myasthenia Gravis Association, said the approval addresses a longstanding unmet need for patients without detectable AChR antibodies, who previously had limited access to targeted therapies.
Generalized myasthenia gravis is a rare autoimmune neuromuscular disorder characterized by muscle weakness and fatigue resulting from impaired communication between nerves and muscles at the neuromuscular junction. Approximately 10–20% of patients with generalized disease do not have detectable acetylcholine receptor (AChR) antibodies, which can make diagnosis and treatment more challenging, particularly when other antibodies (such as anti‑MuSK or anti‑LRP4) are also absent.
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About the Writer
Nikita Jha, BPharm (LinkedIn) a pharmacy graduate specializing in medical writing, with a strong ability to interpret complex medical and regulatory information and translate it into clear, accurate, and evidence-based healthcare content. Known for her attention to detail and precision, she focuses on delivering high-quality scientific communication that supports drug safety and informed decision-making.