FDA Priority Review for Vyvgart in Seronegative MG

The FDA has accepted a supplemental Biologics License Application for Vyvgart (efgartigimod alfa-fcab), seeking an expanded indication for adults with AChR-Ab seronegative generalized myasthenia gravis, based on Phase 3 ADAPT SERON results, and has granted priority review to address an underserved patient population.

The randomized, double-blind, placebo-controlled Phase 3 ADAPT SERON trial (n=119) met its primary endpoint, demonstrating a statistically significant and clinically meaningful improvement in MG-ADL total score with efgartigimod versus placebo (p=0.0068), with a mean 3.35-point change from baseline at day 29 (week 4), according to the sponsor’s topline results.

Safety findings in the submitted dataset were consistent with the established Vyvgart safety profile. The most frequently reported adverse events included respiratory tract infections, headache, and urinary tract infections; infusion-related and hypersensitivity reactions were observed. No new safety signals were identified, although the trial size limits the ability to detect rare adverse events.