FcRn Inhibitors for Treatment of Myasthenia Gravis

Three FcRn inhibitors currently available for myasthenia gravis treatment demonstrate distinct administration profiles and efficacy patterns, though head-to-head comparative trials remain lacking. Efgartigimod requires IV administration only, while batoclimab offers subcutaneous administration and nipocalimab provides both IV and subcutaneous options with prefilled syringe convenience. Nipocalimab distinguishes itself through maintenance dosing every 2 weeks rather than cyclical on-off approaches, potentially providing more consistent disease control and reduced symptom fluctuation.

Clinical trial data suggest nipocalimab achieved the largest absolute MG-ADL score improvements among FcRn inhibitors, though higher placebo responses complicate direct comparisons between studies. The maintenance dosing approach may address “wearing off” phenomena experienced by some patients during off-treatment periods with cyclical therapies. All FcRn inhibitors achieve similar 60% to 70% IgG reduction rates, but individual patient responses vary considerably, making personalized treatment selection crucial for optimal outcomes.

Adverse event profiles differ somewhat between agents, with nipocalimab showing potential for peripheral edema, diarrhea, and transient lipid elevations, while other FcRn inhibitors may cause different adverse effect patterns. The infection risk remains consistent across the class due to IgG reduction, though clinical trial data suggest infection rates comparable to those of placebo groups. Treatment switching between FcRn inhibitors may benefit patients experiencing inadequate responses or tolerability issues with initial therapy, particularly for addressing wearing-off phenomena or optimizing administration convenience based on individual patient preferences and lifestyle factors.