Patients with early symptoms of multiple sclerosis (MS) who are at risk of developing full-blown disease can potentially delay that from happening by taking regular interferon-beta-1a (Avonex/Biogen Idec) injections. That's the opinion of a group of physicians in Italy, who wanted to know whether the drug, a common medication for MS patients, can help stem the progressive loss of brain tissue.
They published the findings of their analysis in the October 23 issue of the journal The Lancet.1
But other experts have a word of caution about jumping to conclusions too quickly.
Does Treatment Delay Brain Atrophy?
Doctors led by Massimo Filippi, MD, a neurologist at the Scientific Institute and University Ospedale San Raffaele in Milan, Italy collected information on patients already enrolled in an earlier, unrelated study known as the Early Treatment of Multiple Sclerosis (ETOMS) trial,2 which tested interferon beta's efficacy against MS-associated relapse.
In that previous research, the medication had showed positive results compared to a placebo in helping to delay the development of full-blown MS in people with early symptoms of the disease. So, Filippi and his team wanted to extend those findings for this latest study.
They followed 131 patients who'd been given regular doses of interferon beta for up to 2 years, and compared their results with those of 132 people who'd taken only a placebo regularly during the study period. About 31 percent of the people in the treatment group during this study progressed to full-blown—known in medical terms as "clinically definite"—multiple sclerosis. That compares to about 47 percent of those taking placebo.
Visualizing Disease Impacts on the Brain
Throughout the study period, the investigators took regular magnetic resonance imaging (MRI) scans of each patient's brain tissue to determine how much had been lost. Mimicking the positive findings about disease progression, Filippi and his colleagues discovered that those given interferon beta lost just over 1% of brain tissue during the study period. But those taking regular placebo doses lost nearly 1.7% brain tissue, nearly twice as much. Both of these findings were considered significant.
"This study has confirmed in a large [group] of patients at the earliest clinical stage of multiple sclerosis that brain [function] loss takes place rapidly, and has shown that 22 micrograms of interferon beta-1a, given subcutaneously once weekly, can alter this process significantly," Filippi commented.
"Whether higher or more frequent doses would enhance or reduce this effect remains untested," he added.
Caveat from Other Experts
In a commentary accompanying the study,3 David Miller, MD, of the Institute of Neurology in London, has a warning about this study. Miller writes that it may be too premature to assume that a reduction in brain atrophy due to the beneficial effect of interferon beta-1a or any other treatment will produce a long-term reduction in a person's disability due to MS. Still, "the report by Filippi and colleagues is encouraging and commends investigators to include brain atrophy as an outcome measure in future trials of potential disease-modifying treatments in multiple sclerosis."
Another MS Treatment Tested
The other interferon beta treatment for relapsing MS is interferon beta-1b (Betaseron/Berlex). It, too, has been shown to reduce brain atrophy. In an open-label study published earlier this year,4 researchers at the National Institute of Neurological Disorders and Stroke tested the effect interferon beta-1b use had on the number of brain lesions and cerebral atrophy in a group of 30 relapsing-remitting MS patients during a three-year period. Each month throughout the study, the investigators conducted MRI and neurological exams with each patient.
At the end of the study, the investigators found that while brain atrophy increased each year, the increase over the entire time was smaller than what occurred from the beginning of the study through the first year, due directly to the use of interferon beta-1b. The number of brain lesions seen in each patient was also significantly reduced, thanks to the drug, the investigators wrote.
"Interferon beta-1b decreases contrast-enhancing lesions and white matter-lesion load over 3 years on therapy, and slows the progression in cerebral atrophy during years 2 and 3," they concluded.
1. Filippi M, Rovaris M, Inglese M et al. Interferon beta-1a for brain tissue loss in patients at presentation with syndromes suggestive of multiple sclerosis: a randomized, double-blind, placebo-controlled trial. Lancet 2004 Oct 23;364(9444):1489-96.
2. Comi G, Filippi M, Barkhof F et al. Effect of early interferon treatment on conversion to definite multiple sclerosis: a randomized study. Lancet 2001 May 19;357(9268):1576-82.
3. Miller DH. Brain atrophy, interferon beta, and treatment trials in multiple sclerosis. Lancet 2004 Oct 23;364(9444):1463-4.
4. Frank JA, Richert N, Bash C et al. Interferon-beta-1b slows progression of atrophy in RRMS: Three-year follow-up in NAb- and NAb+ patients. Neurology 2004 Mar 9;62(5):719-25.
John Martin is a long-time health journalist and an editor for Priority Healthcare. His credits include coverage of health news for the website of Fox Television's The Health Network, and articles for the New York Post and other consumer and trade publications.
