Stopping Treatment
Potential reasons for stopping DMT include relapsing MS or CIS that has been inactive for years; secondary progressive MS that is distant from the relapsing phase and now in a purely neurodegenerative one; age older than 60; and pregnancy.
Citing just a handful of studies in this area, Dr. Coyle pointed to the MSBase Registry of patients with relapsing MS who, on injectables, had no relapse for five years or more. Among 485 patients who stopped DMT versus 854 who continued treatment, time to relapse was similar but time to confirmed disability was shorter in those who stopped treatment. Those who stopped treatment also had an increased risk for entering the progressive stage. In another study of two cohorts who stopped DMT, 11.7% of patients with secondary progressive MS who were stable for two to 20 years, versus 58.8% of patients with relapsing MS, had acute disease within one to two years. The authors noted the secondary progressive MS cohort was older with higher EDSS scores. A retrospective review of patients with MS older than 60 who had been on DMT for more than two years showed that, of the 29.7% who stopped DMT, only one relapsed and just 10.7% reinitiated DMT.
“I would not stop a well-tolerated DMT in relapsing MS,” said Dr. Coyle. “I would continue DMT in CIS if patients were at high risk, even if they had had no disease activity for years. I would discuss stopping therapy in patients with secondary progressive MS who were older than 60, and in very debilitated patients with progressive MS.”
Switching DMTs
In terms of switching, a suboptimal response is likely magnified by delaying therapy, not matching patients well to their initial DMT, and not identifying poor response quickly,” said Dr. Coyle.
Reasons to switch include breakthrough activity—ie, the minimal evidence of disease activity (MEDA) or no evidence of disease activity (NEDA) target not met; MRI activity; poor tolerability; and abnormal laboratory data or clinical complications. Clinicians should consult the AAN practice guidelines for recommendations on when and which DMTs to switch.
Dr. Coyle again cited the MSBase Registry, in which three studies were conducted involving patients with MS who were on interferon beta or glatiramer acetate who had breakthrough attacks or disability. “In one study they switched them to another injectable or fingolimod,” she said. “They did better if they got to fingolimod. Another study involved switching to another injectable or natalizumab. They did better if they were on natalizumab. A third study looked at switching to fingolimod or natalizumab. They did better with natalizumab.”
Dr. Coyle observed that the first one to two years after initiating DMT may be the most important for determining whether a patient is doing well. “A DMT takes a few months to be fully operational,” she said. “If you are switching for breakthrough activity, you need to go to a higher-efficacy DMT. My treat-to target is not NEDA, it is MEDA.”
—Fred Balzac