London, February 7: A common asthma drug can prevent the swelling and weakening of the aorta - the body's largest artery - a serious condition that currently has no treatments, scientist have found. An aortic aneurysm occurs when the wall of the body's largest artery, the aorta, weakens and swells.

The disease progresses slowly and affects some five percent of men and one percent of women over the age of 60. The condition is largely symptom-free and is normally not discovered until late in its development when it threatens to rupture and cause life-threatening haemorrhaging. There are currently no drugs for preventing and treating an aortic aneurysm. Researchers at Karolinska Institutet in Sweden found that a common asthma drug can retard the development of an aortic aneurysm in mice.

"Our results are exciting and open the way for a medical treatment of this serious vascular disease," said Professor Jesper Z Haeggstrom from Karolinska Institutet. In earlier studies, the research group found high levels of particular inflammatory signal substances called leukotrienes in the vascular walls of patients operated on for an aortic aneurysm.

Leukotrienes drive inflammation and are known for their potential to cause asthma. Since the asthma drug montelukast blocks leukotrienes, the team decided to examine whether it could also have an effect on an aortic aneurysm.

Their studies on mice revealed that the treatment did indeed reduce the swelling of the aorta and reduced levels of an enzyme that can break down the vascular wall and a protein involved in inflammatory processes.

"This study is particularly interesting from a therapeutic perspective since montelukast is a safe drug with very few side-effects, which means it can be taken over a long period of time," said Haeggstrom. "In the study, we used drug doses equivalent to those used in the treatment of asthma patients," he said. The researchers hope to be able to start a controlled clinical trial to test the drug's efficacy in patients with an aortic aneurysm.