Recognizing Inadequate Response to FcRn Inhibitors in MG

This episode, titled ‘Recognizing Inadequate Response to FcRn Inhibitors in MG,’ features panelists discussing how they recognize when FcRn-targeted therapy is no longer providing sufficient disease control. Faculty distinguish patients who show little or no initial response from those who respond but do not achieve adequate depth or durability. Because FcRn therapies generally act relatively quickly, a complete absence of response can become apparent early, while partial responders may require additional observation to understand whether repeated treatment or a different dosing approach will provide deeper control.

The panel also discusses symptoms between treatment cycles and apparent wearing off. Rather than assuming that loss of control always reflects declining drug efficacy, experts emphasize that MG itself can change over time and that new disease activity or other medical factors may alter treatment requirements. Cyclic dosing can further complicate interpretation when patients repeatedly lose control between courses.

Faculty then consider retrospective real-world observations of patients transitioned to nipocalimab from other therapies. Reported reasons for switching included inadequate efficacy, worsening or fluctuating symptoms, and dissatisfaction with cyclic treatment. Most patients were reported by their clinicians to improve after the transition. The panel interprets these findings as support for a less linear treatment paradigm in which clinicians may move between therapeutic mechanisms or potentially switch between therapies within the FcRn class when disease control remains insufficient.

In the next episode, ‘Switching Within or Across Drug Classes Safely in MG,’ panelists will examine how clinicians decide between an FcRn-to-FcRn switch and a change in mechanism, as well as practical strategies for safely transitioning between therapies.