Interferon is usually the first treatment doctors prescribe for people with relapsing-remitting MS.

Interferon has been used for many years. It is known to be safe, as well as effective in preventing new relapses and worsening of MS.

However, patients taking interferon may experience several side effects, reducing their quality of life. Such side effects include headaches, muscle aches, flu-like symptoms, and reactions at sites of injection.

Patients who react badly to these side effects tend to miss some doses, reducing the effectiveness of the treatment.

To improve patients’ quality of life, several new drugs have been studied. One of these is a new kind of interferon, pegylated interferon, given by injection.

Pegylated interferon lasts longer, so needs to be taken less often, with fewer side effects.

Last July, a group of researchers from the USA and Europe published the results of a clinical trial called ADVANCE.

In this two-year study, patients with relapsing-remitting MS were treated with this new kind of interferon. In the 1,332 patients that completed the study, the effectiveness of pegylated interferon was compared with a placebo.

The researchers found that pegylated interferon given by injection every two weeks was significantly more effective than the placebo in decreasing the number of new relapses and the risk of developing disability.

Pegylated interferon is now expected to enter a post-marketing phase. This is when drugs are submitted for approval by the international medicine agencies and so can be prescribed by doctors.

However, as with any drug, pegylated interferon will not be suitable for all people with relapsing remitting MS. But it seems that it may be a good alternative to the other kinds of interferon.