For MS patients already on a higher-efficacy DMT, how do you assess if it is time to switch to a new DMT when they have new clinically-silent MRI brain lesions?

Generally, patients have annual MRIs to screen for new active lesions. If there is still ongoing disease activity, such as new Gad+ lesions or expanding T2 lesions, a DMT switch is often considered. If a patient is already on a high-efficacy DMT, one could consider a lateral switch to another high-e...

With high-efficacy therapy, my treatment target is "no inflammatory disease activity". If there are any clinical relapses or new MS lesions on MRI, I will always use that as an opportunity to discuss the implications of breakthrough disease with patients. In my experience, breakthrough disease is us...

I do not use an absolute number of new lesions as the sole threshold for switching a patient who is already receiving a high-efficacy DMT. Instead, I interpret new MRI activity in the context of the timing, number, size, and location of the lesions; the mechanism and expected onset of efficacy of th...

I do not use a strict numerical threshold for new MRI lesions, but I do have a practical approach. In my own practice, breakthrough inflammatory activity on high-efficacy therapy has been quite uncommon. I can think of only one or two patients who developed a new relapse or new MRI lesions, and in t...