An outright cure for asthma could be possible in five years if researchers establish that existing drugs for people with brittle bones can be safely used to treat sufferers’ lungs.

The scientists discovered the cause of the debilitating condition and also how to stop it in findings they described as “incredibly exciting”, The Daily Telegraph reported.

Their work could also lead to new drugs to treat people with chronic bronchitis and chronic obstructive pulmonary disease.

Asthma UK, which helped pay for the research, said the drugs called calcilytics - which are used to treat osteoporosis - could provide a way to treat the underlying cause of asthma for the first time.

One of the researchers, Professor Daniela Riccardi, from Cardiff University School of Biosciences, said: “If we can prove that calcilytics are safe when administered directly to the lung in people, then in five years we could be in a position to treat patients and potentially stop asthma from happening in the first place.”

When an irritant, such as pollution, is inhaled, the scientists found that calcium-sensing receptor cells in asthmatics over-react, causing potentially dangerous narrowing of the airways. However when calcilytics were inhaled, they stopped this from happening.

The researchers tested the drugs on airway tissue from mice and humans.

Dr Samantha Walker, director of research and policy at Asthma UK, said: “This hugely exciting discovery enables us, for the first time, to tackle the underlying causes of asthma symptoms.

“Five per cent of people with asthma don't respond to current treatments so research breakthroughs could be life changing for hundreds of thousands of people. If this research proves successful we may be just a few years away from a new treatment for asthma, and we urgently need further investment to take it further through clinical trials.”