A large-scale study revealed potential adverse reactions to beta-interferon (IFN-β) therapy, one of the most common treatments used for relapsing-remitting multiple sclerosis (RRMS).
In the study titled “Evaluating the safety of β-interferons in MS: A series of nested case-control studies,” the authors aimed to identify associations between IFN-β treatment and potential adverse events in a real-world clinical setting.
“Once a drug is released on the market, there are very few ways to systematically monitor adverse events,” Helen Tremlett, senior author of the study and a professor in the department of medicine at the Djavad Mowafaghian Centre for Brain Health in British Columbia, Canada, said in a press release. “Clinical trials cannot identify all adverse effects of a drug treatment partly due to small sample sizes and relatively short follow-up periods.”
The research team evaluated the healthcare records of 2,485 patients with RRMS who were registered at the British Columbia Multiple Sclerosis Clinic between 1995 and 2008. Among these patients, 1,031 (41.5 percent) were treated with IFN-β and followed for a mean period of eight years.
Researchers found that these RRMS patients presented a higher incidence rate of some adverse effects. Beta-interferon exposure was found to be associated with an 1.8-fold increased risk of stroke, 1.6 times higher risk of migraine, and 1.3 times higher risk of developing depression and hematologic abnormalities.
“Beta interferons are generally thought of as having a favorable safety profile, especially compared to the newer therapies for multiple sclerosis. And that is still the case; our study does not change that,” Tremlett said. “However, very few studies had comprehensively and quantitatively assessed their safety in real world clinical practice. Our findings complement and extend on previous observations.”
Some of the therapy’s side effects reported in the study had already been recognized and included in the safety profile of IFN-β, such as migraine, hematologic abnormalities, and depression. But stroke had not been recognized as a potential adverse event to beta-interferon treatment.
“Further advances could enable personalized or precision medicine where patients who are at increased risk of having an adverse reaction can be identified. This could help guide discussions about individual treatment options and considerations,” Tremlett said.
Despite the potential adverse effects associated with IFN-β treatment, the authors also found beneficial effects. People undergoing this therapy longer than two years showed a reduced risk of bronchitis and upper respiratory infections, which can be a common problem among these patients.
“It is important for patients with multiple sclerosis to have ongoing review of the benefits and risks of therapy, and to identify supportive strategies, such as diet and exercise, that could optimize their brain health,” said Anthony Traboulsee, co-author of the study and director of the MS Clinic at the University of British Columbia.