AVONEX effectiveness

Understanding the potential benefits

AVONEX works in 3 key areas

**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. 

Two separate studies

Studies lasted 2-3 years

Over 600 people

STUDY 1

Syringe one

158 people

took 30 mcg of AVONEX by intramuscular (IM) injection once weekly

Syringe two

143 people

took a placebo by IM injection once weekly

STUDY 2

Syringe one

193 people

took 30 mcg of AVONEX by IM injection once weekly

Syringe two

190 people

took a placebo by IM injection once weekly

In these clinical trials, AVONEX was found to:

Help slow disability progression

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.

  • The percentage of people with increased disability at 2 years was 22% for AVONEX-treated patients and 35% for placebo-treated patients

People taking AVONEX were 37% less likely to have increased disability at 2 years. 

Help reduce relapses

In people who took AVONEX for the full 2-year study (Study 1), AVONEX reduced relapses by 32% compared with placebo.

  • The annual relapse rate was 0.61 per patient-year in the AVONEX-treated group and 0.90 per patient-year in the placebo-treated group

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.

  • The annual relapse rate was 0.67 per patient-year in the AVONEX-treated group and 0.82 per patient-year in the placebo-treated group

Help reduce risk of relapse at 3 years

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.

Help reduce brain lesions on MRI

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.††

  • At the start of the study, people in the AVONEX group had 3.2 Gd+ lesions vs 0.8 lesions after 2 years on AVONEX

In the 3-year study (Study 2), AVONEX reduced the size of T2 lesions by 91% compared with placebo at 18 months.

  • Change in T2 lesion volume from the start of the study was 28 mm3 in the AVONEX group versus 313 mm3 in the placebo group

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.

See a list of common relapsing MS terms

More to check out

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*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 January 2021-April 2023.

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