Almost half the patients with early arthritis symptoms in a trial saw a significant improvement in their condition after a year.
The drug, MabThera (rituximab), stops the deterioration of the joints in people showing the first signs of the disease. Researchers believe it should help to keep patients in employment and living independently for longer.
Experts said the results showed the drug could have a “dramatic effect” in treating up to half of Britain’s 500,000 rheumatoid arthritis sufferers. Charities said its findings were “encouraging”.
It is hoped that the drug could be approved for use on the NHS within 18 months, because it is already used for the treatment of severe arthritis and certain cancers. Rheumatoid arthritis, an auto-immune disease, differs from osteoarthritis, which is due to wear and tear.
It is not known what causes rheumatoid arthritis but some families are prone to the condition and it is more common in women, so hormones may play a part.
About 40 per cent of patients are forced to stop work during the first five years of their illness.
The direct and indirect cost of the condition is estimated at up to £4.75 billion a year, largely due to lost productivity.
Treatment of the disease involves dampening the body’s immune system with a series of drugs to reduce the damage to the joints and slow the disease’s progress.
However, the new research, which involved 755 patients, showed that for 30.5 per cent of sufferers, their joint damage stopped after six months of taking MabThera in combination with methotrexate – the standard treatment for rheumatoid arthritis. This compared with 12.5 per cent of those on methotrexate alone.
After 12 months, almost half the patients had improved, according to the study presented to the European League Against Rheumatism in Copenhagen, Denmark.
However, for around one in five patients there was no significant improvement. It is not clear why the combination does not work in some patients but it is not unusual in rheumatoid arthritis for responses to vary.
It is also unclear how long the six-monthly doses will continue to be effective as the combination has been tested only for up to a year so far. Longer trials are ongoing. Prof Paul Emery, of the University of Leeds and Eular’s president-elect, said: “This is important news.
“It has shown good results and we are beginning to target individual therapies at individual patients.” Prof Emery said he hoped the treatment would be approved by the watchdog Nice – the National Institute for health and Clinical Excellence.
A course of MabThera costs £3,492 – significantly less than the £12,000 cost of similar drugs for the immune system, which are also used for the treatment of rheumatoid arthritis. Because MabThera dampens the immune system it can have side effects including hypertension, nausea and upper respiratory tract infections.