High-Potency SPMS Meds Limit Relapses, Study Finds
High-potency therapies are more effective at reducing the frequency of symptom relapses in people with secondary progressive multiple sclerosis (SPMS) than low-potency medications, a 10-year study showed.
Notably, there was no difference in the effectiveness of either high- or low-potency medicines to limit the progression of disability.
“When the goal is to alleviate ongoing relapse activity, more potent therapy is justified. But when the goal is to limit disability progression in secondary progressive MS, both types of drugs show comparable effectiveness,” study lead Tomas Kalincik, MD, PhD, said in a press release.
The study, “Effects of High and Low Efficacy Therapy in Secondary Progressive Multiple Sclerosis,” was published in the journal Neurology.
The first diagnosis that most people with multiple sclerosis (MS) receive is relapsing-remitting MS (RRMS), which is marked by flare-ups of symptoms, known as relapses, followed by periods of partial or complete recovery (remissions).
More than half of RRMS patients eventually are diagnosed with secondary progressive MS (SPMS), characterized by slow, but steady, worsening of disability, with or without continued relapses.
During the RRMS stage, patients are treated with more-potent, high-efficacy, disease-modifying medications that effectively reduce flare-ups and slow disease progression. But little is known whether these high-efficacy medications help those who already have transitioned to SPMS.
“Multiple sclerosis is a complicated disease to treat and must be closely monitored as it is managed with various medications, some of which can have serious side effects,” said Kalincik.
“High-efficacy medications are prescribed in early multiple sclerosis to more aggressively treat the disease and have been found to more effectively prevent flare-ups and modify progression, but less is known about how effective these therapies may be later when relapsing-remitting MS transitions to secondary progressive MS,” he said.
Now, Kalincik and his team at the University of Melbourne in Australia, with collaborators in several European countries, followed people with SPMS who received either high- or low-efficacy (less-potent) medicines for 10 years, and measured relapses and disease progression.
For this study, 1,000 participants were selected from the MSBase and OFSEP databases, which are large observational studies, and divided into two groups based on whether they received high- or low-efficacy therapeutics.
High-efficacy medicines prescribed after SPMS onset included Tysabri (natalizumab), Lemtrada (alemtuzumab), Novantrone (mitoxantrone), Ocrevus (ocrelizumab), rituximab, Mavenclad (cladribine), and Gilenya (fingolimod). Low-efficacy (potency) therapies were interferon beta, Copaxone (glatiramer acetate), and Aubagio (teriflunomide).
Participants in the high- and low-efficacy groups were matched for disability levels and SPMS duration. A lag time also was added to represent the time until the patient experienced benefits of the medication.
The results revealed that study participants with active SPMS — relapses within the past two years — treated with high-efficacy medicines experienced less-frequent relapses (30% fewer) compared to those on low-potency therapies. This represented 0.17 relapses per year for the high-efficacy group versus 0.27 relapses per year with low-efficacy medications.
In comparison, there was no difference in relapse frequency between high- or low-efficacy groups in patients with inactive disease. There also was no difference between high- or low-efficacy medicines in slowing the progression of disability.
“In treated patients with SPMS, high-efficacy therapy is superior to low-efficacy therapy in reducing relapses in patients with active, but not those with inactive, SPMS,” the investigators wrote. “However, more potent therapies do not offer an advantage in reducing disability progression in this patient group.”
“Our study finding that high-efficacy therapies are superior to low-efficacy therapies only in reducing relapses in people with active secondary progressive MS provides valuable guidance for neurologists when choosing the most effective therapies for people with this form of MS,” Kalincik said.
The researchers noted that the medicines were not studied individually, and thus each therapy may affect symptoms and disability differently. They recommended each treatment be examined separately in future studies.