Reply To: What happened to efgartigimod/Vyvgart for seronegative MG?

[Community Member]

This is why there is no FDA approval for us seronegative ab patients.

https://www.argenx.com/news/argenx-announces-positive-topline-phase-3-adapt-trial-results

The trial was done on both AChR positive and negative patients. There are 2 reasons the FDA did not approve the drug for seronegative and musk patients, is because the sample was too small and

Percentage of efgartigimod responders on the MG-ADL score in the AChR-antibody negative patient population was consistent with the AChR-Ab+ patient population, but a greater placebo response was observed in this cohort.