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Treatments > Medications Used In MS


Brand Name Chemical Name


Interferon beta-1a

Primary Usage in MS

Generic Available
Disease-modifying agent No
This medication is taken by injection.

Rebif is a medication manufactured by a biotechnological process from one of the naturally-occurring interferons (a type of protein). It is made up of exactly the same amino acids (major components of proteins) as the interferon beta found in the human body. A controlled clinical trial in relapsing-remitting MS compared three groups-those receiving 22mcg three times per week, those receiving 44mcg three times a week, and those receiving placebo. Over the two-year study, the two experimental groups demonstrated a lower relapse rate, prolonged time to first relapse, a higher proportion of relapse-free patients, a lower number of active lesions on MRI, and delay in progression of disability, when compared to the placebo group. Rebif currently available at the 44mcg dose in pre-filled syringes ready for subcutaneous injection.

Approval by the U.S. Food and Drug Administration (FDA)
Rebif is approved for the treatment of patients with relapsing forms of MS to decrease the frequency of clinical exacerbations and delay the accumulation of physical disability.

Reporting on the outcome of the EVIDENCE trial, which compared Rebif and Avonex (both interferon beta-1a), the FDA added the following information to the labeling of Rebif:
"Patients treated with Rebif 44 mcg [micrograms] sc [delivered subcutaneously] tiw [3 times per week] were more likely to remain relapse-free at 24 and 48 weeks than were patients treated with Avonex 30 mcg im [delivered intramuscularly] qw [once per week]."

Proper Usage
Rebif is given three times a week subcutaneously (between the fat layer just under the skin and the muscles beneath). The physician or nurse will instruct you in the injection procedure, using a specially designed set of training materials. Do not attempt to inject yourself until you are sure that you understand the procedures.

When beginning treatment, it is recommended that you start at 8.8 mcg three times a week and gradually increase over a 4-week period to the 44mcg dose in order to reduce the side effects. A starter kit with 22mcg syringes is available to facilitate the gradual increase in dose.

Rebif should be administered at the same time of day, on the same days of the week, preferably in the late afternoon. Doses must be at least 48 hours apart.

Rebif should be stored in the refrigerator. Storage at room temperature without exposure to heat or light is permissible for up to 30 days. Do not allow the medication to freeze.

Do not reuse needles or syringes. Dispose of the syringes as directed by your physician and keep them out of the reach of children.

Since flu-like symptoms are a fairly common side effect during the initial weeks of treatment, it is recommended that the injection be given at bedtime. Taking acetaminophen (TylenolŪ) or ibuprofen (AdvilŪ) immediately prior to each injection and during the 24 hours following the injection will also help to relieve the flu-like symptoms.

Rebif should not be used during pregnancy or breast-feeding, or by any woman who is trying to become pregnant. Women taking Rebif should use birth control measures at all times. If you want to become pregnant while being treated with Rebif, discuss the matter with your physician. If you become pregnant while using Rebif, stop the treatment and contact your physician.

There was no increase in depression reported by people receiving Rebif in the clinical trial. However, some patients treated with interferons, including Rebif, have become seriously depressed, and depression and suicidal thoughts are known to occur with some frequency in MS. It is recommended that individuals with a history of severe depressive disorder be closely monitored while taking Rebif. Anyone who experiences significant feelings of sadness or helplessness, or feels like hurting him- or herself or others, should speak with a friend or family member right away and contact the physician as soon as possible.

Rebif can affect liver function. Your physician may ask you to have regular blood tests to make sure that your liver is working properly. If you notice that your skin or the whites of your eyes become yellow, or if you are bruising more easily than usual, contact your physician. A post-marketing case of liver failure has been reported in a person taking Rebif along with another medication that was potentially toxic to the liver. While this type of problem is extremely rare, people need to make sure that their physician is aware of any history of liver disease, alcoholism, or other liver problems, as well as of all the medications they are taking.

Because of the potential of Rebif to affect the levels of white blood cells, red blood cells, and platelets in a person's system, blood tests are recommended at regular intervals. Thyroid function tests are recommended every 6 months in patients with a history of thyroid dysfunction.

Possible Side Effects
Common side effects include flu-like symptoms (fatigue, chills, fever, muscle aches, and sweating) and injection site reactions (swelling, redness, discoloration, and pain). Most of these symptoms tend to disappear over time. If they continue, become more severe, or cause significant discomfort, be sure to talk them over with your physician. Contact your physician if the injection sites become inflamed, hardened, or lumpy, and do not inject into any area that has become hardened or lumpy.

Most of these symptoms will tend to disappear after the initial few weeks of treatment. If they continue, become more severe, or cause you significant discomfort, be sure to talk them over with your physician.

Symptoms of depression, including ongoing sadness, anxiety, loss of interest in daily activities, irritability, low self-esteem, guilt, poor concentration, indecisiveness, confusion, and eating and sleep disturbances, should be reported promptly to your doctor.

MS LifeLines

Medication Index

Other Medications Used as Disease-Modifying Agents

The Disease-Modifying Drugs
Information on the disease-modifying drugs (Betaseron, Avonex, Copaxone, Novantrone, Rebif, and Tysabri). Includes how each is taken, side effects, benefits, and available help.

Is an Oral Disease-Modifying Drug on the Horizon?
February 2006

Neutralizing Antibodies
August 2005

National MS Society Disease Management Consensus Statement
Early intervention recommendations by the Medical Advisory Board of the National MS Society regarding use of the current MS disease-modifying agents

Pregnancy Registries for the Interferon Beta Products Prescribed for Women with MS
The FDA issued guidelines requiring the manufacturers of Avonex, Betaseron, and Rebif to develop pregnancy registries to monitor women who have taken one of these drugs within a week of becoming pregnant or while they were pregnant.

Managing Injection Site Reactions

For professional help with injection anxiety, please discuss the following training program with your nurse or counselor.
Self-Injection Anxiety Counseling (SIAC)

About Interferons

Reprinted with permission from Rosalind C. Kalb (ed.), Multiple Sclerosis: The Questions You Have—The Answers You Need, 3rd Edition. New York: Demos Medical Publishing, Inc., 2004

Last updated September 21, 2006