Generalized myasthenia gravis (gMG) is an autoimmune neuromuscular disorder in which pathogenic autoantibodies against acetylcholine receptors or muscle-specific kinase impair neuromuscular transmission, producing fluctuating fatigable weakness. A substantial proportion of patients experience persistent symptoms despite established immunosuppression.

The neonatal Fc receptor (FcRn) recycles IgG; selective FcRn antagonism rapidly reduces circulating IgG — including disease-relevant autoantibodies — with a favorable selectivity profile versus non-specific immunosuppression. Phase 3 ADAPT trial data demonstrated statistically significant improvements in the Myasthenia Gravis Activities of Daily Living scale in AChR antibody-positive gMG patients, with a manageable safety profile. A subcutaneous formulation has further expanded clinical flexibility. Active investigation continues to refine optimal dosing frequency, predictors of sustained response, and long-term immunological effects of chronic FcRn blockade. Positioning FcRn inhibitors relative to established immunosuppressants and complement inhibitors and monitoring long-term IgG effects are evolving practice considerations. Neurologists and neuromuscular specialists managing AChR- or MuSK-positive gMG will benefit from peer discussion of FcRn-targeted therapy integration.

How do you currently position FcRn inhibitors relative to established immunosuppressants and complement inhibitors in gMG, particularly in patients with inadequate corticosteroid or azathioprine responses? What clinical and serological factors most influence your decisions regarding treatment frequency and duration with FcRn-targeted therapy in gMG?

Generalized myasthenia gravis (gMG) is an autoimmune neuromuscular disorder driven by pathogenic IgG autoantibodies — predominantly anti-acetylcholine receptor (AChR) or anti-muscle-specific kinase (MuSK) — that impair neuromuscular transmission and produce fatigable, fluctuating weakness. Despite established immunotherapies, a substantial proportion of patients experience persistent symptoms or refractory disease, underscoring ongoing unmet need.

The neonatal Fc receptor (FcRn) normally recycles IgG antibodies to extend their systemic half-life; blocking FcRn with a targeted antagonist accelerates IgG catabolism — including disease-relevant AChR and MuSK autoantibodies — without broadly impairing cellular immunity. The phase 3 ADAPT trial demonstrated that an Fc fragment-based FcRn antagonist produced statistically significant and clinically meaningful improvements in Myasthenia Gravis Activities of Daily Living (MG-ADL) scores in AChR-antibody-positive patients, with rapid onset of action and a favorable safety profile. The availability of a subcutaneous formulation co-administered with recombinant human hyaluronidase has further expanded administration flexibility, reducing infusion burden and improving convenience for patients and clinicians. Ongoing investigations are clarifying optimal treatment frequency, response predictors, and long-term immunological effects of sustained FcRn blockade. The evolving role of FcRn antagonism relative to complement inhibitors and broad immunosuppressants represents a key area of clinical discussion.

How do you currently position FcRn inhibitors relative to complement inhibitors and conventional immunosuppressants in the gMG treatment algorithm — particularly for patients with inadequate corticosteroid or steroid-sparing agent responses? What clinical and serological factors most influence your decisions regarding cycle frequency, treatment duration, and individualization of FcRn antagonist therapy in gMG?