**The link between brain lesions and the progression of relapsing MS has not been confirmed.
In clinical trials of more than 600 people (301 in Study 1, 383 in Study 2) with relapsing MS, AVONEX was tested against a placebo, or “fake” treatment—a standard way to measure if a drug works as expected.
At the end of the 2-year clinical trial (Study 1), 78% of people taking AVONEX had no increase in disability, compared with 65% of people taking placebo.
People taking AVONEX were 37% less likely to have increased disability at 2 years.
In people who took AVONEX for the full 2-year study (Study 1), AVONEX reduced relapses by 32% compared with placebo.
When including the people enrolled in the study who didn’t take AVONEX for the full 2 years, AVONEX reduced relapses by 18% compared with placebo.
In the 3-year clinical study (Study 2) of people who had only experienced one flare-up,† people taking AVONEX were 44% less likely to have a second relapse at 3 years compared with people taking placebo.
In the 2-year study (Study 1), AVONEX reduced the number of gadolinium-enhanced (Gd+) lesions by 75% compared with the beginning of the study.††
In the 3-year study (Study 2), AVONEX reduced the size of T2 lesions by 91% compared with placebo at 18 months.
†A study of people who had experienced a first flare-up and had lesions consistent with MS on MRI. In this study a relapse was defined as 1) a new clinical sign of MS that differed from the patient’s presentation when they entered the study or 2) an increase of at least 1.5 Expanded Disability Status Scale (EDSS) points or 3) further worsening noted at 2 months or the patient withdrew before completing 2 months of treatment.
††The placebo group experienced a 30% reduction from baseline in the number of Gd+ lesions after 2 years.
*This information is an estimate derived from the use of information under license from the following IQVIA information service: IQVIA NPA® NBRx monthly data for the period March 2015–February 2021.