While early use of high-efficacy treatments lowers relapse rates among patients with relapsing-remitting multiple sclerosis (MS) compared to lower-efficacy ones, starting these therapies earlier may only impact the accumulation of disability among young patients, according to data presented at the 7th Joint ECTRIMS-ACTRIMS Meeting in Paris, France.
Earlier treatment with high-efficacy drugs might also allow patients to recover better from disability, said Tomas Kalincik, from the University of Melbourne in Australia, who presented the data.
Researchers are not in agreement whether therapies that are more efficient but have more side effects should be started early or be reserved for MS patients in later disease stages. Therefore, studies of how patients fare after early initiation of high-efficacy drugs are important to guide treatment decisions.
To support these decisions, the research team analyzed data available through the global MSBase study to track relapse rates and disability development linked to various types of treatment.
For the study, “Timing of high-efficacy disease modifying therapies for relapsing-remitting multiple sclerosis,” the team included information on patients treated with Sanofi Genzyme’s Lemtrada (alemtuzumab), Biogen’s Tysabri (natalizumab), or Novartis’ Gilenya (fingolimod) as high-efficacy therapies. Patients who started treatment within four or six years of their diagnosis were included.
First, researchers compared 257 patients treated with high-efficacy therapies to 1,102 patients who started low-efficacy treatments — interferon beta, Copaxone (glatiramer acetate), or Aubagio (teriflunomide) — during the first four years of their MS diagnosis.
To make sure that comparisons were valid, they paired patients with similar characteristics for each analysis.
The team found that annualized relapse rates were nearly halved in the high-efficacy group compared to patients treated with low-efficacy therapies. They did not see a difference in disability accumulation or improvement between high-efficacy and first-line treatments in this group.
They then compared 485 patients who started such therapies within four years of their diagnosis to 1,180 who started within six years. They noted a smaller, but significant, lowering of relapse rates, and again, no effect on disability accumulation.
When comparing people on high- and low-efficacy treatments who started within one, between two and four, or more than four years after a diagnosis, they noted that the difference in relapse rates between the groups became smaller with time. They again noted no difference in disability outcomes in this analysis.
In those treated with high-efficacy therapies within a year of diagnosis, researchers, however, noted a trend toward more disability accumulation in patients on first-line treatment. This trend appeared to become greater with time.
But other factors are also known to impact disability accumulation. Therefore, the team looked at how the different treatment approaches impacted disability accumulation in patients with specific features. They discovered that in younger patients, high-efficacy treatment did lower disability accumulation.
“The superiority of higher-efficacy therapy to first line therapy in preventing accumulation of disability is more pronounced in younger patients,” Kalincik said.
Moreover, they noted that patients who were treated with high-efficacy drugs had a much larger chance of disability improvement, particularly if they started the treatment after more than four years upon a diagnosis.
Researchers admitted that the study was limited in that it only studied short-term disability outcomes, up to six years. Further research is needed to shine more light on how first-line and high-efficacy therapies perform in the long run to limit disability accumulation.