Multiple Sclerosis Drugs May Not Delay Disability
Interferon Beta Treatment Did Not Slow Progression of Disability in Study
Different Study, Different Outcome
After adjustment for other influences on disease progression, treatment with interferon beta was not found to be associated with a reduction in progression to disability.
These findings appear to conflict with an Italian trial published earlier this year, says Timothy Coetzee, PhD, who is chief research officer of the National MS Society.
In that study, investigators followed nearly 1,200 MS patients who had had the disease for at least a decade.
They found that patients who took interferon beta and other disease-modifying therapies were less likely to progress from relapsing-remitting MS to a more advanced form of the disease.
Coetzee adds that the different results of the two studies illustrate the limitations in the measures used to assess MS therapies.
"Because of the wide variability in MS, it is likely that these drugs do delay disease progression in some patients, but not in others," Coetzee says. "The problem is that we currently have no tools to help us identify patients who will and will not respond."
Drug Maker Responds to Study
In a written response to the new study, Avonex manufacturer Biogen Idec Inc. says the findings are contradicted by other trials.
"In carefully controlled clinical trials, Avonex has demonstrated slowing of disability progression, and regulators worldwide have reviewed and confirmed the positive impact of Avonex on slowing disease progression," spokesman Jeff Boyle writes.