A POTENTIALLY major breakthrough in the treatment of cystic fibrosis has been made in Dundee after patients were given a substance most commonly found in green tea.

Scottish scientists, working alongside counterparts in Italy and France, found that a combination of an existing drug and a common antioxidant reversed key features of the most common form of the condition.

The exciting results produced by the small trial, involving 10 patients, will offer hope to tens of thousands worldwide and have led to plans for a larger study in which it is hoped the findings will be verified.

If the results are repeated, the work of the researchers could lead to a completely new approach to therapy for the commonest form of the genetic disorder.

Dr Anil Mehta, a clinical reader at Dundee's Medical Research Institute who has been working on cystic fibrosis for more than 20 years, described the results as an "extremely encouraging first step".

"The results suggest that it might be possible to arrest the disease," Dr Mehta said. "Obviously we are still at an early stage but if these results are replicated in a placebo-controlled clinical trial, then I believe it could be a potential game-changer.

"However, we will need more support to make this happen. These drugs are already licensed, and being off-patent means the cost of developing a drug therapy should not be prohibitive."

In Scotland, one child in every 2,345 people is born with cystic fibrosis. The condition mainly causes difficulty breathing and lung infections but also affects the liver, pancreas and intestines. People diagnosed with the condition have a drastically reduced life expectancy, although it is improving thanks to medical advances.

The average predicted survival for someone with cystic fibrosis currently stands at 41, while in the 1950s, a child born with the condition would not have been expected to live to attend primary school.

The eight-year-old son of former Prime Minister Gordon Brown, Fraser, was diagnosed with the condition as a baby. Mr Brown has previously spoken of his hope that a cure will be found.

In the Dundee trial, Cysteamine, an already licenced drug, was given to patients alongside epigallocatechin gallate, an antioxidant most commonly found in green tea.

Researchers found that the two substances given together reduced inflammation in nine out of ten of the patients' airways and also dramatically reduced the levels of salt in their sweat - another characteristic feature of the disorder.

Dr Mehta's long-term ambition is to develop drugs to give to babies soon after diagnosis to prevent their lungs declining.

He added: "I would like to thank all those who have volunteered in Dundee to donate their airway cells since 1991. They are the true, selfless folk who made this possible. The work shows the value of international co-operation in attempts to beat this very nasty disease."

The Cystic Fibrosis Trust offered its congratulations to Dr Mehta and his team, but warned that the results of the trial should be treated with caution.

A spokeswoman for the charity said: "Dr Anil Mehta and his team must be congratulated for the progress they have made. However this is a very small sample size and talk of a breakthrough towards cure is premature.

"A much larger-scale trial is now required before this can be declared to be an effective therapy for cystic fibrosis.

"The Cystic Fibrosis Trust funds a range of research and would welcome a funding application from Dr Mehta through any of our existing funding channels."