Long-term exposure of at least three years of beta-interferon therapies such as Rebif or Avonex may increase the survival of multiple sclerosis (MS) patients, a population-based study suggests.
The study reporting the findings, titled “Beta-interferon and mortality in multiple sclerosis: a population-based international study,” was presented Friday at the ongoing ECTRIMS-ACTRIMS Meeting in Paris, France (Oct. 27-28).
The body naturally produces proteins called interferons that play a vital role in the immune system. Beta-interferons are released in the final stages of an immune attack to dampen inflammation and shut down the body’s immune response.
Therapies based on beta-interferons have successfully been used to treat relapsing MS, including Rebif, Avonex, Betaferon, Plegridy, and Extavia.
However, it is not clear if beta-interferon prolongs survival in people with MS. To answer this question, a team led by researchers at the University of British Columbia, in Canada, investigated how beta-interferon treatment affects all-cause mortality by testing it in a real-world clinical setting.
The team analyzed prospectively collected data from relapsing-remitting MS (RRMS) patients living in British Columbia, Canada, and in Rennes, France. Patient data including sex, birth date, Expanded Disability Status Scale (EDSS) scores, and disease-modifying treatments (DMTs) were crossed with population-based administrative databases.
Patients from Canada were also crossed-referenced for drug prescriptions filled, universal healthcare registration, hospital admissions, and physician visits.
Patients who participated in the analysis had not been treated with DMTs at the start of the study and were followed for 17 years.
The analysis included a total of 7,009 RRMS patients, mostly women, with a median age of 42 years when entering the study. Researchers used as a control group up to 20 MS patients randomly selected but matching in sex, age, calendar year, and EDSS at study entry.
During follow-up, 30% of the patients received a beta-interferon therapy, 11% received Copaxone (glatiramer acetate), and 12% received another form of DMT, including MS-specific immunosuppressants.
Researchers then estimated how beta-interferon treatment associated with all-cause mortality.
The results showed that compared to patients who had minimal or no beta-interferon therapy, those who had treatment for over three years had an increased survival rate. Exposure to beta-interferon for less than three years had no effect on survival.
Overall, the results suggest that “IFNB [beta-interferon] was associated with a lower risk of all-cause mortality among MS patients treated in clinical practice over an observation period of up to 18 years. Findings were consistent across two geographically distinct regions including North America (Canada) and Europe (France),” the team concluded.