Video
Author(s):
A. Gordon Smith, MD, FAAN, discusses the findings and implications of phase 3 ADAPT trial and open-label extension study evaluating the use of efgartigimod in the treatment of patients with myasthenia gravis.
A. Gordon Smith, MD, FAAN: We have several studies that inform us about efgartigimod in treating myasthenia. The first and most obvious is the phase 3 ADAPT study. This showed significant improvement in Myasthenia Gravis Activity of Daily Living scale, or MG-ADL and other secondary endpoints in the trial. The trial was designed in a way that poses some challenge to us clinically, because there was a treatment phase and then patients were monitored until they worsened a sufficient degree that they were then retreated. This is reflected in how the drug is labeled and so it's not dosed in the trial the way that we typically dose drugs in clinical practice where we do an infusion every X number of weeks and then adjust. This is something that is currently being worked out in clinical practice. It works in my experience effectively, but I think that there's hopefully going to be more data coming in the future about the optimal way of dosing this. Again, additional studies that are going on in real-world experience will inform that. There is an open-label phase 3 extension of the ADAPT study that involved about 150 patients that were followed on average about a year and over that year, open-label extension, efgartigimod remained effective and was well-tolerated, suggesting that FcRn inhibition is a not only effective approach to treating myasthenia gravis, but it's one that seems to last for at least the period of time we have been following patients so far.
Transcript edited for clarity