Relapsing multiple sclerosis patients who begin taking Betaferon/Betaseron (interferon beta-1b) immediately after the first MS-related neurologic symptoms appear may realize slower disease progression than those who delay treatment, according to a study evaluating the therapy’s effects over a decade in patients enrolled in a Phase 3 clinical trial.
The study, “The 11-year long-term follow-up study from the randomized BENEFIT CIS trial,” published in the journal Neurology, found that patients put on Betaferon/Betaseron early in their disease course went without a first relapse for longer time periods and had lower annualized relapse rates. (The interferon beta-1b treatment produced by Bayer is known as Betaferon in Europe; in the U.S., it is marked as Betaseron.)
MS often starts after an acute or subacute episode of neurologic dysfunction known as clinically isolated syndrome (CIS). Over time, as lesions accumulate, up to 85% of people diagnosed with CIS will develop MS.
A number of studies have shown that using disease-modifying MS therapies in people with CIS can delay their disease’s conversion to multiple sclerosis. However, the long-term effects of starting treatment this early were limited.
The Phase 3 BENEFIT (NCT00185211) study began as a prospective, two-year, international, double-blind and placebo-controlled trial in which patients were assigned to receive either Betaferon/Betaseron or placebo. After conversion to clinically definitive MS (CDMS) or two years, patients on placebo could switch to Betaferon/Betaseron or another treatment.
The five- and eight-year extensions of BENEFIT showed that patients who initiated Betaferon/Betaseron treatment immediately after CIS had a delay in conversion to definitive MS, and a reduction in the annualized relapse rates compared to those who started treatment two years post-CIS or after their second neurological event.
For this study, the researchers assessed the longer-term effects of Betaferon/Betaseron treatment on disease course, 11 years after CIS. They enrolled 278 patients from BENEFIT, accounting for 59.4% of its original 469 participants. They found that after 11 years of treatment, those who received Betaferon/Betaseron early still showed a significantly lower risk of CDMS conversion, lower overall annualized relapse rates, and longer time to first relapse: 1,888 days in the treatment group versus 931 days in placebo group patients.
In addition, early treatment patients had better Paced Auditory Serial Addition Task-3 total scores, which measure sustained and divided attention, as well as the capacity and rate of information processing. But no differences in Expanded Disability Status Scale (EDSS) scores or conversion to secondary progression were found between the two arms.
Employment rates remained high in both groups, even after 11 years, and health resource utilization was low in each group.
“Although the delay in treatment was relatively short, several clinical outcomes favored earlier treatment,” the researchers concluded, noting the persistent long-term benefits in clinical disease activity, as assessed by the improvements in time to CDMS, time to first relapse, and relapse rates. These findings, they said, reinforce the importance of starting therapy with Betaferon/Betaseron as soon as possible after initial signs of MS onset.