Potential risks of common MS treatment
In a comprehensive study, UBC researchers identified potential adverse reactions of a commonly used multiple sclerosis drug. The study aimed to identify potential adverse events related to beta-interferon treatment for relapsing-remitting multiple sclerosis by analyzing health records of over 2000 British Columbians with multiple sclerosis between 1995 and 2008. The researchers found that there was a 1.8-fold increased risk of stroke, a 1.6-fold increased risk of migraine, and a 1.3-fold increased risk of both depression and abnormalities in the blood with taking beta interferon for multiple sclerosis.
Helen Tremlett, PhD, senior author of the study and a professor in the Department of Medicine at the Djavad Mowafaghian Centre for Brain Health, identified that after a drug is released on the market there are very few ways to systematically monitor adverse events, and that clinical trials cannot identify all adverse effects of a drug treatment (partly due to small sample sizes and relatively short follow-up periods).
Tremlett reiterated that beta interferons are generally thought of as having a favorable safety profile, especially compared to newer multiple sclerosis therapies, and that the study does not change that fact. However, few studies had comprehensively and quantitatively assessed their safety in real world clinical practice.
Researchers stress that patients and physicians should not change their treatment plans. The study is based on population-level data, and the risk to individual patients will vary greatly depending on individual factors. Tremlett hopes that further advances could enable personalized or precision medicine where patients who are at increased risk of having an adverse reaction can be identified to help guide discussions about individual treatment options and considerations.
In addition to the negative effects, Tremlett and colleagues found a reduced risk of bronchitis and upper respiratory infections with tak-ing beta interferon for more than 2 years. The study was published in Neurology (www.neurology.org/content/early/2017/05/12/WNL.0000000000004037.short).
The study was funded by the Canadian Institutes of Health Research and the National Multiple Sclerosis Society in the United States. Hilda de Jong, PhD, first author of the study, was funded by the Michael Smith Foundation for Health Research and the MS Society of Canada.