BENEFIT Follow-Up Study: Early Treatment of MS Can Delay Permanent Disabilities

Treating patients who are showing the first signs of multiple sclerosis with beta interferon significantly delays the onset of clinically estab-lished MS and the occurrence of permanent disabilities. These are the results of a follow-up to the BENEFIT study recently published in the prestigious journal The Lancet. Bayer Schering Pharma pre-sented these and other findings from a 16-year long-term study with beta interferon at the 23rd ECTRIMS Congress (Congress of the European Committee for Treatment and Research in Multiple Sclero-sis), which was held from 11-14 October in Prague.

468 patients with the first signs of MS had participated in the BENE-FIT study at 98 clinics in 20 countries. 292 of them were given beta interferon every other day for two years. 176 subjects were given a placebo until MS was clinically established.

90% of the participants opted to participate in a follow-up phase in-volving treatment with beta interferon. The aim was to compare the degree of neurological impairment in patients treated at an early stage with those whose treatment began later. It showed that early treatment had reduced the risk of disability progression by 41% after three years.

Mysterious disintegration of neurones

About 2.5 million people suffer from multiple sclerosis worldwide. This chronic, mostly relapsing-remitting disease usually occurs for the first time in people between the ages of 20 and 40, affecting women more often than men. It is the most common disease of the central nervous system in young adults. Yet despite intensive research, the causes of the disease are still largely unknown.

What is regarded as certain is that MS is an autoimmune disease. The immune system – which is actually trained to ward off "enemies" such as viruses and bacteria – becomes unbalanced and regards the body's own tissue as an "enemy." During an acute attack of the dis-ease, one or more local centers of inflammation form in the brain or the spinal cord. The attacks are caused by so-called activated T-cells, which are able to overcome the blood-brain barrier. These misrouted immune cells trigger a signal cascade that ultimately leads to the attack on nerve tissue, thus destroying the myelin sheath; this is a thin protective layer surrounding the nerve cells and their processes, rather like insulating material surrounds a copper cable. "Short cir-cuits" occur at places where the myelin sheath is missing or has scarred, blocking impulse conduction between nerve cells.

The type of neurological deficits depends very much on which parts of the nervous system are affected by the disease: for example, pa-tients can experience blurred vision, speech and coordination disor-ders, paralysis of the arms or legs, or attacks of dizziness.

An endogenous protein can help

MS is still incurable today. Yet the disease can be treated over the longer term with variants of an endogenous neurotransmitter. Inter-ferons – the great hope against cancer in the 1970s – are effective against autoimmune diseases because they inhibit inflammation.

Bayer Schering Pharma's interferon, which was approved for Europe in 1993, can reduce the frequency of MS attacks by 30 to 50%, so that the patient may possibly be spared from at least one in three attacks. Patients can administer the drug under the skin themselves every two days using an injection device.

Early treatment delays disabilities

As a rule, it takes quite a long time before the diagnosis of MS is fully clinically established, and irreversible damage can already be done to the nervous system during this time. These study results now en-courage doctors to start therapy early, for this can improve the pa-tient's quality of life. The latest findings from a 16-year long-term fol-low-up using beta interferon also indicate that the damage done dur-ing the early stage of MS correlates with the degree of cognitive loss suffered in the later course of disease. Early treatment could there-fore also be crucial for maintaining cognitive skills.

Neutralizing antibodies do not diminish beta interferon's effec-tiveness

When Betaferon® is administered, some patients develop neutraliz-ing antibodies (NAbs). But however many antibodies there are in the blood, they do not reduce the effectiveness of early treatment with interferon beta. At the same time, Nabs had reverted over the three-year observation period. This was also shown by the evaluation of the BENEFIT data.