PROVEN RESULTS

When compared to a placebo, Rebif^® (interferon beta-1a) was proven effective in treating relapsing multiple sclerosis (RMS) in 3 important ways.

This was shown in a placebo-controlled study of Rebif for RMS called PRISMS.^‡ A placebo, which is an inactive substance, is used for comparison against the active ingredient of the drug to determine its effectiveness and safety profile. As part of this type of clinical trial, people understand that they may or may not get the drug as part of the study. Many clinical trials are performed this way. This type of study is commonly used to determine whether the drug is effective and to evaluate its safety profile.

* Lesions detected with both T1-weighted gadolinium-enhanced (T1-Gd+) and PD/T2-weighted MRI.
^† Refers to new lesions and total lesion burden or area as defined in the AAN and MS Council guidelines.
^‡ Prevention of Relapses and Disability by Interferon β-1a Subcutaneously in Multiple Sclerosis.

The PRISMS study included people with a range of disability in RMS based on their Expanded Disability Status Scale (EDSS) scores. The EDSS is used to track physical disability over time. The scale goes from 0 (minimum) to 10 (maximum). People in the PRISMS study had EDSS scores ranging from 0 to 5.0 on the scale when they entered the study. 

The 2-year PRISMS study looked at 560 people to see how they responded. One hundred eighty-nine people took Rebif 22 mcg; 184 took Rebif 44 mcg; and 187 took a placebo, all given under the skin 3 times a week. The overall results for people taking Rebif 44 mcg showed:

The number of lesions represent new or enlarging lesions, per patient per scan.

^* Gadolinium is a contrast medium injected prior to MRI scans. It passes through breaches in the blood-brain barrier and is therefore used to highlight new and active lesions. The usage of
gadolinium greatly enhances the sensitivity of a T1-weighted MRI.
^† Refers to new lesions and total lesion burden or area as defined in the AAN and MS Council guidelines.
^‡From a subgroup of 134 patients in the PRISMS study who received 11 consecutive monthly T2 and T1-Gd+ MRI scans beginning 1 month before treatment initiation.
^§ Median number of lesions, per patient per scan, based on comparisons from rank-based ANOVA. Lesions detected with both T1-Gd+ and T2-weighted MRI. Median = a value in an
ordered set that has an equal number of values higher and lower.
^|| The number of lesions represents new or enlarging lesions, per patient per scan.
^¶ Disability progression was defined as an increase of at least 1 point in the EDSS that was sustained for at least 3 months.

A SUBSET OF PEOPLE FROM THIS STUDY WITH GREATER LEVELS OF DISABILITY AT STUDY ENTRY SHOWED SIGNIFICANT RESULTS AT 2 YEARS

Although people in the PRISMS study had a range of disability at the beginning of the study, Rebif was also shown to be effective versus placebo for a subset of people who started taking Rebif and had greater disability (EDSS scores of 3.5 to 5.0). People with EDSS scores in this range may start to experience mobility and other functional limitations. In this subset of people with greater disability at the beginning of the study, 31 people took Rebif 44 mcg 3 times a week under the skin and 28 people took a placebo.

1% of those taking placebo in the PRISMS study stopped taking placebo because of adverse events.

It's important to inform your healthcare provider of any side effects you experience. There may be things you can do to help manage them.

Please see Important Safety Information below and the Rebif Medication Guide and Prescribing Information at the top of this website, and speak with your healthcare provider for more information.

^* In this subset of people with greater disability, 31 people took Rebif 44 mcg 3 times a week under the skin and 28 people took a placebo.
^†Lesions detected with both T1-Gd+ and T2-weighted MRI.
^‡ Refers to new lesions and total lesion burden or area as defined in the AAN and MS Council guidelines.
^§Based on comparisons from rank-based ANOVA.
^||M edian = a value in an ordered set that has an equal number of values higher and lower.
^¶ Disability progression was defined as an increase of at least 1 point in the EDSS that was sustained for at least 3 months.

Learn more about the head-to-head study involving Rebif →

The people in these photos are not actual Rebif patients.

Next: Head-to-head study →