Drugs that treat ms

Disease-modifying treatments change the course of MS by manipulating the immune system in a variety of ways. Researchers found clues for a new and promising therapy when they began looking at the behavior of interferons. These chemical messengers tell other immune cells what to do when the body is exposed to a foreign invader such as a virus. In MS, they may help keep the cells and chemicals that damage myelin in check.

How interferons reduce symptoms in MS is not totally clear, but it is thought that they block the release of myelin-damaging chemicals that cause swelling and inflammation. They can also reduce the number of new lesions found on MRI scans, suggesting that interferons can decrease myelin destruction. Interferons may also prevent immune cells from crossing the protective blood-brain barrier to enter the central nervous system where they don't belong.

In 1993, the first interferon, IFNb-1b (Betaseron®), was approved by the Food and Drug Administration for the treatment of MS. The studies showed Betaseron was able to decrease the number of attacks and in some cases, stop the disease from worsening. Two other types of interferon, which are both slightly different in composition from Betaseron, are IFNb-1a (Avonex®) and IFNb-1a (Rebif).

Glatiramer acetate (Copaxone®) and mitoxantrone (Novantrone®) are other immune therapies used to change the course of MS, but each manipulates the immune system in a manner different from that of interferons.

It is difficult to tell how well a treatment is working because symptoms of MS naturally come and go. Although attacks sometimes continue to occur, they tend to be shorter and less severe in patients receiving these medications. Still, it is unlikely that any of these medications will reverse existing disabilities.

Medications should be selected by a physician based on the following:

The number of relapses
The severity of symptoms
The degree of disability
The type of MS
The duration of the disease
The prognosis
Findings of MRI scans
The type of injection preferred
The severity of treatment side effects