Multiple Sclerosis: Copaxane and the Interferon Drugs: Avonex, Betaseron and Rebif

Interferons are a group of immune system proteins -- alpha, beta, and gamma -- produced by the body. They act in different ways to control the activity of the immune system. They also have antiviral properties. (Remember that another theory regarding relapses in people who already have MS is that they may be triggered by viruses.) So far, experts have found that interferon beta is effective in treating multiple sclerosis (MS).

There are three forms of interferon beta on the market in the U.S.: Avonex, Betaseron and Rebif.

These interferon beta drugs are very similar to the interferon beta naturally produced in the body.

Avonex

• FDA approved for the treatment of relapsing MS.
• Drug shown to reduce exacerbations of MS and reduce size of brain lesions and delay the time to a second MS exacerbation by treating the initial demyelinating event if seen on MRI (along with symptoms). (Demyelination is the destruction of myelin, which is the fatty sheath that surrounds and protects the nerve fibers.)
• Drug also shown to reduce progression of MS disability, if started in the early stages of the disease.
• Drug given weekly by an injection into the muscle

Betaseron

• FDA approved for the treatment of relapsing forms of MS.
• Drug shown to reduce the number of MS exacerbations, reduce the severity of exacerbations and extend the time between exacerbations. Additionally, the drug stabilizes the size of brain lesions.
• Drug given as an injection every other day subcutaneously (between the fat layer under the skin)

Rebif

• FDA approved to treat relapsing forms of MS.
• Drug shown to reduce relapse rate, and reduce the active lesions on MRI and delay the progression of disability.
• Also shown to delay the progression of disability if started early in the course of the disease.
• Drug given three times a week subcutaneously (between the fat layer under the skin)

Side Effects of Interferon Drugs:

• Flu-like symptoms (fatigue, chills, fever, muscle aches and sweating during initial weeks of treatment. Therefore it's recommended that the injection be taken at bedtime. Taking Tylenol or Advil or Motrin before each injection and during the 24 hours after the injection may help relieve the symptoms
• Reactions at the site of injection (swelling, redness, discoloration and pain). Contact your health care provider if the injection site becomes hardened. Do not inject into that site.
• Interferon drugs can cause ongoing sadness, anxiety, irritability, guilt, poor concentration, confusion and difficulties sleeping or eating. These symptoms should be reported to a health care professional immediately.

Precautions

• Women who are pregnant or breastfeeding or trying to become pregnant should not use interferon drugs; birth control measures should be used.
• People with a history of depression should be closely monitored and interferon drugs can worsen depression symptoms.
• These drugs can affect the functioning of the liver. Avonex has been linked to severe liver injury, and liver failure in a few patients taking the drug. Therefore your doctor will perform regular blood tests to be sure the liver is functioning normally.
• Interferon drugs can affect the blood cells and thyroid gland function as well. Therefore, your health care provider will perform regular blood testing to follow this.