(Ivanhoe Newswire) -- An inhaled corticosteroid (budesonide) coupled with a long-acting beta2-agonist (formoterol) can provide significant improvement of asthma symptoms with less reliance on high doses of inhaled steroid, according to a new study.

Researchers at the Firestone Institute for Respiratory Health in Ontario, Canada, studied the effects of various combinations of medicine on asthma symptoms in 2,760 asthma patients at 246 centers in 22 countries.

The patients were divided into three treatment groups: a bud/form combination twice a day and as needed for relief, bud/form twice a day plus terbutaline (a short-acting beta2-agonist) as needed, and budesonide twice a day plus terbutaline as needed.

Results show a 45-percent reduction in the exacerbation rate of asthma symptoms, a reduction in overall severe exacerbation levels, improved symptom control and lung function, and less sleep interruption in those who took the bud/form combo compared with the other two drug combinations.

Researchers also noted the bud/form combination helped maintain a reduction in asthma attacks severe enough to require medical attention, using a corticosteroid dose that was one-fourth the amount in the budesonide/terbutaline combo.

The study also shows no evidence of a tolerance developing to the bud/form treatments, with patients maintaining their results for one year.