A POTENT new pill has been developed which harnesses the body’s natural inflammation-busting ability to beat crippling arthritis.

The “smart” drug not only helps relieve the devastating joint inflammation which leaves sufferers in daily agony but researchers also say it has no side-effects.

The breakthrough offers real hope that the hundreds of thousands of Britons struck down by rheumatoid arthritis could soon be treated with a powerful medication which uses their own body to fight the disease naturally.

Current drug treatments, once the disease has taken hold, have unpleasant and potentially dangerous side-effects.

Methotrexate, or MTX, is the standard treatment but for one in three patients it causes side-effects including nausea, diarrhoea and hair loss.

Now Dr Ulrich Flogel at Dusseldorf university in Germany has developed a drug which dramatically eases joint inflammation without harmful side-effects.

Rheumatoid arthritis affects 690,000 people in Britain and is more prevalent among women.

It is a chronic autoimmune disease which occurs when the immune system attacks the joints.

Patients suffer severe pain and stiffness in their joints as well as fatigue and loss of mobility and it is estimated that the total cost to the UK economy of the condition is at least £4.75billion a year.

One patient in four is registered disabled within three years of diagnosis with three-quarters moderately to severely disabled within 20 years.

This new research, published in the journal Science Translational Medicine, showed that the drug called chet-AMP reduces inflammation without leading to a drop in blood pressure.

The drug works by harnessing a molecule called CD73 which the body naturally uses to fight inflammation. Chet-AMP is activated only when CD73-covered immune cells are present in inflamed joints, which helps keep nearby tissues unaffected.

Ailsa Bosworth, chief executive at the National Rheumatoid Arthritis Society, said: “People with rheumatoid arthritis often have to take anti-inflammatory drugs alongside disease modifying anti-rheumatic drugs to combat the symptoms of their rheumatoid arthritis and taken long term, this type of medication can have unpleasant side-effects.

“Although this study is still at an early stage we welcome any research that advances our knowledge in this field and could lead to better treatment options and improved outcomes for patients.”

The disease can strike at a young age, unlike the more common osteoarthritis, which mainly strikes older people.

It usually affects hands and feet, although any of the body’s joints can become inflamed and painful. It can also lead to crippling flare-ups. Although there is no cure for rheumatoid arthritis, a variety of treatments are available that can slow down the condition and keep joint damage to a minimum. The earlier someone starts treatment, the more effective it is likely to be.

The current more common treatment involves painkillers and anti-inflammatory drugs which tackle the pain and swelling. Disease-modifying anti-rheumatic drugs or DMARDS – of which MTX is the most common – are used to slow down the progression of the disease.

Jane Tadman, from Arthritis Research UK, said: “While this work is interesting, it is very early, experimental research in mice.

“There is a long way to go before any claims that this is a new drug, without side-effects, can be substantiated.”