Volunteers with an allergic reaction to one or more fungi showed significant improvements in their asthma after taking antifungal itraconazole pills, Professor David Denning at University Hospital of South Manchester and colleagues reported.

Airborne fungi can worsen asthma but the study published in the American Journal of Respiratory and Critical Care Medicine is the first to show that antifungal therapy can actually improve severe asthma symptoms, the researchers said.

'Severe asthma affects between five and 10 per cent of adult asthmatics and probably 25 to 50 per cent of these patients showed allergy to one or more fungi,' Prof Denning said in a statement.

Asthma is an inflammatory disease causing wheezing, coughing and laboured breathing that can be life threatening. It affects an estimated 300 million people worldwide.

Itraconazole, marketed as Sporanox by Johnson & Johnson unit Janssen Pharmaceutical, is a broad-spectrum antifungal drug that is also available generically.

Asthma treatments include GlaxoSmithKline's Advair which combines two ingredients to ease the condition - a steroid to fight inflammation and a so-called beta agonist to open airways by relaxing muscles that tighten during an asthma attack.

Prof Denning and colleagues compared itraconazole with a placebo among 58 men and women with severe asthma at four hospitals in Northwest England.

Nearly 60 per cent of the volunteers showed significant improvement in their asthma symptoms during the eight months they took the antifungal drug.

Their asthma - marked by runny noses, sneezing and hay fever-like symptoms - worsened within four months after people stopped taking the pills, the researchers added. All those in the study had tested positive for a fungal allergy.

'This pioneering study indicates that fungal allergy is important in some patients with severe asthma, and that oral antifungal therapy is worth trying in some difficult-to-treat patients,' Professor Robert Niven of the University of Manchester, who worked on the study, said in a statement. -- REUTERS