Rebif® (interferon beta‐1a) Efficacy Results
We're sorry, but we're unable to process your login. Please try again.
We're sorry, you are not authorized to access this site. Please contact your local Merck representative if you have any inquiries.
This page requires you to register for an account with Merck. Please login with your Merck account credentials below, or register for a new account.

Log in with Merck
{* #signInForm *}
{* signInEmailAddress *}
{* currentPassword *}
{* captcha *}
{* /signInForm *}

PROVEN RESULTS

Rebif was proven effective in a clinical study vs placebo

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

List of the 3 important ways Rebif was proven effective: 1.Slow disability progression 2.Reduce rate of flare-ups 3.Reduce the number of new or enlarging brain lesions

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.

Rebif was effective for people with a range of disability

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 →

IMPORTANT SAFETY INFORMATION

Before beginning treatment, you should discuss the potential benefits and risks associated with Rebif with your healthcare provider.

Rebif can cause serious side effects. Tell your healthcare provider right away if you have any of the symptoms listed below while taking Rebif.

  • Behavioral health problems including depression and suicidal thoughts. You may have mood problems including depression (feeling hopeless or feeling bad about yourself), and thoughts of hurting yourself or suicide
  • Liver problems or worsening of liver problems including liver failure. Symptoms may include nausea, loss of appetite, tiredness, dark colored urine and pale stools, yellowing of your skin or the white part of your eye, bleeding more easily than normal, confusion, and sleepiness. During your treatment with Rebif you will need to see your healthcare provider regularly and have regular blood tests to check for side effects
  • Serious allergic and skin reactions. Symptoms may include itching, swelling of your face, eyes, lips, tongue or throat, trouble breathing, anxiousness, feeling faint, skin rash, hives, sores in your mouth, or skin blisters and peels
  • Injection site problems. Symptoms at the injection site may include redness, pain, swelling, color changes (blue or black), and drainage of fluid
  • Blood problems. Rebif can affect your bone marrow and cause low red and white blood cell and platelet counts. In some people, these blood cell counts may fall to dangerously low levels. If your blood cell counts become very low, you can get infections and problems with bleeding and bruising. Your healthcare provider may ask you to have regular blood tests to check for blood problems
  • Seizures. Some people have had seizures while taking Rebif

Rebif will not cure your MS but may decrease the number of flare-ups of the disease and slow the occurrence of some of the physical disability that is common in people with MS.

Do not take Rebif if you are allergic to interferon beta, human albumin, or any of the ingredients in Rebif.

Before you take Rebif, tell your healthcare provider if you have or have had any of the following conditions:

  • mental illness, including depression and suicidal behavior
  • liver problems, bleeding problems or blood clots, low blood cell counts, seizures (epilepsy), or thyroid problems
  • you drink alcohol
  • you are pregnant or plan to become pregnant. It is not known if Rebif will harm your unborn baby
  • you are breastfeeding or plan to breastfeed. Rebif may pass into your breastmilk. Talk with your healthcare provider about the best way to feed your baby if you take Rebif

Tell your healthcare provider about all medicines you take, including prescription and over-the-counter medicines, vitamins and herbal supplements.

 

The most common side effects of Rebif include:

  • flu-like symptoms. You may have flu-like symptoms when you first start taking Rebif. You may be able to manage these flu-like symptoms by taking over-the-counter pain and fever reducers. For many people, these symptoms lessen or go away over time. Symptoms may include muscle aches, fever, tiredness, and chills
  • stomach pain
  • change in liver blood tests

Tell your healthcare provider if you have any side effect that bothers you or that does not go away.

These are not all the possible side effects of Rebif. For more information, ask your healthcare provider or pharmacist.

Call your doctor for medical advice about side effects. 

You are encouraged to report negative side effects of prescription drugs to FDA. Visit www.fda.gov/medwatch, or call 1-800-FDA-1088.

IMPORTANT SAFETY INFORMATION

Before beginning treatment, you should discuss the potential benefits and risks associated with Rebif with your healthcare provider.

Rebif can cause serious side effects. Tell your healthcare provider right away if you have any of the symptoms listed below while taking Rebif.

  • Behavioral health problems including depression and suicidal thoughts. You may have mood problems including depression (feeling hopeless or feeling bad about yourself), and thoughts of hurting yourself or suicide
  • Liver problems or worsening of liver problems including liver failure. Symptoms may include nausea, loss of appetite, tiredness, dark colored urine and pale stools, yellowing of your skin or the white part of your eye, bleeding more easily than normal, confusion, and sleepiness. During your treatment with Rebif you will need to see your healthcare provider regularly and have regular blood tests to check for side effects
  • Serious allergic and skin reactions. Symptoms may include itching, swelling of your face, eyes, lips, tongue or throat, trouble breathing, anxiousness, feeling faint, skin rash, hives, sores in your mouth, or skin blisters and peels
  • Injection site problems. Symptoms at the injection site may include redness, pain, swelling, color changes (blue or black), and drainage of fluid
  • Blood problems. Rebif can affect your bone marrow and cause low red and white blood cell and platelet counts. In some people, these blood cell counts may fall to dangerously low levels. If your blood cell counts become very low, you can get infections and problems with bleeding and bruising. Your healthcare provider may ask you to have regular blood tests to check for blood problems
  • Seizures. Some people have had seizures while taking Rebif

Rebif will not cure your MS but may decrease the number of flare-ups of the disease and slow the occurrence of some of the physical disability that is common in people with MS.

Do not take Rebif if you are allergic to interferon beta, human albumin, or any of the ingredients in Rebif.

Before you take Rebif, tell your healthcare provider if you have or have had any of the following conditions:

  • mental illness, including depression and suicidal behavior
  • liver problems, bleeding problems or blood clots, low blood cell counts, seizures (epilepsy), or thyroid problems
  • you drink alcohol
  • you are pregnant or plan to become pregnant. It is not known if Rebif will harm your unborn baby
  • you are breastfeeding or plan to breastfeed. Rebif may pass into your breastmilk. Talk with your healthcare provider about the best way to feed your baby if you take Rebif

Tell your healthcare provider about all medicines you take, including prescription and over-the-counter medicines, vitamins and herbal supplements.

 

The most common side effects of Rebif include:

  • flu-like symptoms. You may have flu-like symptoms when you first start taking Rebif. You may be able to manage these flu-like symptoms by taking over-the-counter pain and fever reducers. For many people, these symptoms lessen or go away over time. Symptoms may include muscle aches, fever, tiredness, and chills
  • stomach pain
  • change in liver blood tests

Tell your healthcare provider if you have any side effect that bothers you or that does not go away.

These are not all the possible side effects of Rebif. For more information, ask your healthcare provider or pharmacist.

Call your doctor for medical advice about side effects. 

You are encouraged to report negative side effects of prescription drugs to FDA. Visit www.fda.gov/medwatch, or call 1-800-FDA-1088.

lightbox image