ISA2 to Master Protocol ARGX-999-2-MG-2000 - an Exploratory, Phase 2a, Randomized, Double-Blinded, Placebo-Controlled Study to Evaluate the Safety, Tolerability, and Efficacy of Empasiprubart IV Monotherapy in Participants With AChR-Ab Seropositive Generalized Myasthenia Gravis | Arctuva