Chiron and Berlex MS drug shows long-term safety

The follow-up study, named 16-LTF, provides clinical assessment of patients who first enrolled in the Betaseron (interferon beta-1b) pivotal trial between 1988 and 1990. The results of the Betaseron pivotal trial led to the US approval of Betaseron 250mcg for the treatment of relapsing-remitting MS.

Focusing on the preliminary assessment of the study arm for the currently marketed dose of Betaseron 250mcg compared to placebo, the results reveal that patients treated with Betaseron 250mcg in the pivotal trial are more likely to report continued ability to walk unaided or using aids. Half of the patients originally assigned to the Betaseron 250mcg group reported being able to walk with or without assistance, compared with 41% originally assigned to the placebo group.

In addition, 94% of the patients originally assigned to the Betaseron 250mcg group are still alive, compared with 82% of the patients originally assigned to the placebo group.

“While it is premature to draw firm conclusions from preliminary data, I am particularly struck by the mortality trend among patients in the placebo arm appearing to be three-fold different than that of patients receiving Betaseron,” said Dr Barry Arnason, professor of the department of neurology at the University of Chicago. “The reasons for this difference are unknown right now, but hopefully, we will get a clearer understanding of why this difference occurred when the study is completed and the data analyzed more fully.”

Betaseron was the first therapy approved in the US to treat relapsing-remitting MS, the most common form of the disease. Over a decade since its approval, tens of thousands of patients worldwide have now used Betaseron in controlled research studies and in clinical practice, providing the broadest experience of any MS therapy.