Efgartigimod Use May Be Beneficial in MG Management | Rare Diseases Today

Much of the existing literature has assessed the safety and efficacy of efgartigimod in adult patients with generalized myasthenia gravis. Limited research has examined efgartigimod in pediatric patients with generalized myasthenia gravis. Anna Kostera-Pruszczyk, MD, PhD , of the Medical University of Warsaw in Poland, and colleagues conducted a phase 2/3 trial to evaluate the efficacy and safety of efgartigimod in pediatric patients with anti-acetylcholine receptor antibody–positive (AChR-Ab+) generalized MG.

The researchers presented the interim study findings at the 2026 European Academy of Neurology Congress. The study involved two juvenile patients aged 2 to 17 years. The study used a staggered design.

In part A, the researchers collected data on patient response to a single confirmatory dose for 8 weeks or longer. In part B, the study team also evaluated the efficacy of a multiple-dose treatment response for 18 weeks or longer. The findings showed that efgartigimod use led to a decline in both AChR-Ab and overall IgG serum levels.

Other data from part B of the study indicated that the average overall Myasthenia Gravis Activities of Daily Living score decreased by -3.5 from baseline to 1 month during cycle 1 and −4.0 during cycle 2. Notably, 80% of the cycle 2 cohort and roughly 73% of the cycle 1 group reached minimal symptom expression.

“Efgartigimod treatment was well tolerated in adolescents and resulted in decreased levels of both total IgG and AChR-? Abs, similar to those observed in adult studies. Clinically meaningful improvements in MG-?

ADL and QMG occurred, with many participants achieving MSE. Efgartigimod may address an unmet need in juvenile gMG therapy,” the researchers wrote. References 2026 European Association of Neurology Annual Meeting.

Abstract No. OPR-084 . https://www.ean.org/congress2026