Disease modifying drugs

There are several branded drugs available on the NHS which can reduce the number of MS relapses, known as ‘disease modifying drugs’:

• Avonex (drug name, beta interferon)
• Rebif (beta interferon)
• Betaferon (beta interferon)
• Copaxone (glatiramer acetate)

Beta interferon and glatiramer acetate can reduce the number of relapses by about 30 per cent for people with relapsing remitting MS. Clinical trials with beta interferon also show some benefit for people with secondary progressive MS, but only where relapses are the cause of increasing disability.

Some people with ‘highly active’ relapsing remitting MS may benefit from a fifth disease modifying drug, Tysabri (natalizumab).

Tysabri has been shown to reduce the number of relapses by 68 per cent for people with relapsing remitting MS. In addition, people taking the drug had, after two years, less disability than expected.

These drugs do not help everyone with MS. Unfortunately, they have not been shown to help people with primary progressive MS. For people with secondary progressive MS, beta interferon may reduce the number of relapses but does not affect the underlying progression.

Which disease modifying drugs are available on the NHS?

Beta interferon, glatiramer acetate and Tysabri can be prescribed on the NHS for anyone who meets certain criteria. Below is a brief summary of the main criteria. For further details, see Disease modifying drugs.

• Beta interferon and glatiramer acetate are available throughout the UK for people with MS who can walk 10 metres, with or without assistance, if they have had one ‘disabling’ relapse in the past year, or two ‘clinically significant’ relapses in the past two years.
• Currently, Tysabri is available for people with ‘highly active’ relapsing remitting MS, in England, Wales and Northern Ireland. In Scotland, the Scottish Medicines Consortium advised local health boards not to pay for Tysabri. The MS Society is campaigning to have this decision reversed and a review was due in September 2007. Visit www.mssocietyscotland.org.uk for the latest information.

Other drugs are being studied, including alemtuzumab (also known as Campath 1-H). This is not currently licensed in the UK for MS. Results after two years of a clinical trial show that people with ‘early active’ relapsing remitting MS who took the drug had fewer relapses and less disability than would normally be expected. Final trial results are expected at the end of 2007.

The drugs mitoxantrone and intravenous immunoglobulin may be useful but are not currently licensed in the UK for MS. Some neurologists also use azathioprine (Imuran), though few consider this to be very effective in MS.

How early in the course of MS should disease modifying drugs be used?

There is a range of views. At one end, there is a view that, as it is possible to get axonal damage at the very beginning of the condition, treatment with disease modifying drugs should begin at diagnosis or even when people present with their very first symptoms and have an abnormal scan. Others point out that a considerable number of people remain very well for years, even decades, and they should not be subjected to the hassle and side effects of these drugs. A sensible approach probably lies somewhere between these two views.

In the meantime, it is important that the search for better treatments continues. While very important, disease modifying drugs are only one component of the management of MS.

See also Information, diet and exercise