A Phase 3 Study to Evaluate the Efficacy and Safety of Efgartigimod IV in Patients With Acetylcholine Receptor Binding Antibody Seronegative Generalized Myasthenia Gravis

The primary purpose of this study is to measure the efficacy and safety of efgartigimod IV compared to placebo in participants with Acetylcholine Receptor Binding Antibody (AChR-Ab) seronegative Generalized Myasthenia Gravis (gMG). The study consists of a Part A where participants will be randomized to receive either efgartigimod IV or placebo IV and a Part B where participants completing part A will receive open-label efgartigimod IV. Participants will be in the study for up to (approximately) 3.5 years.

NCT Number	NCT06298552
Lead Sponsor	argenx
Conditions	Generalized Myasthenia Gravis, gMG, Myasthenia Gravis, Generalized, Myasthenia Gravis
Enrollment	119 participants
Start Date	2024-04-16
Primary Completion	2025-06-30 (estimated)
Study Completion	2028-06 (estimated)
Updated on ClinicalTrials.gov	2026-08-10