For those who suffer with asthma, the symptoms of coughing, wheezing, shortness of breath and/or chest tightness can be daunting. About 25 million Americans have asthma — 7.6 percent of adults and 8.4 percent of children.

Asthma has been increasing since the early 1980s in all age, sex, and racial groups. According to the Centers for Disease Control and Prevention, 1 in 13 people have asthma.

Asthma is a leading chronic disease in children and the top reason for missed school days. In 2013, about 13.8 million missed school days were reported due to asthma.

Most people with asthma need two kinds of medications to treat asthma — quick-relief medicines and long-term control medicines.

Severe asthma includes up to 20 percent of asthma patients who have frequent and severe symptoms despite aggressive therapy with anti-inflammatory and other controller medications. These patients often have fixed and progressive reductions in pulmonary function that do not reverse completely either after intense acute or long-term therapy.

Current treatments for severe asthma often include high doses of corticosteroids, such as prednisone, to control exacerbations. Reducing the need for corticosteroids with alternative treatments is preferable because these medications are associated with serious side effects from prolonged use, including multi-organ toxicities and immunosuppression.

In a recent study, Dr. Parameswaran Nair, staff respirologist at St. Joseph's Healthcare Hamilton and professor of medicine at McMaster University, along with a team of researchers, found that an antibody called dupilumab is effective in treating severe asthma in place of high doses of prednisone.

The team randomly assigned 210 patients with oral glucocorticoid-treated asthma to receive add-on dupilumab (at a dose of 300 mg) or a placebo every two weeks for 24 weeks. Glucocorticoid doses were adjusted in a downward trend from week 4 to week 20 and then maintained at a stable dose for four weeks.

The primary end point was the percentage reduction in the glucocorticoid dose at week 24. Key secondary end points were the proportion of patients at week 24 with a reduction of at least 50 percent in the glucocorticoid dose and the proportion of patients with a reduction to a glucocorticoid dose of less than 5 mg per day.

Severe exacerbation rates and the forced expiratory volume in 1 second (FEV₁) before bronchodilator use were also assessed. The percentage change in the glucocorticoid dose was -70.1 percent in the dupilumab group compared with -41.9 percent in the placebo group (P<0.001). Eighty percent vs. 50 percent of the patients had a dose reduction of at least 50 percent, 69 percent vs. 33 percent had a dose reduction to less than 5 mg per day, and 48 percent vs. 25 percent completely discontinued oral glucocorticoid use.

Unlike the previous studies, dupilumab was shown to be effective regardless of patients' eosinophil levels. Despite the reduced prednisone dose, patients in this study not only experienced a decrease in asthma exacerbations, but their lung function also improved significantly.

According to Dr. Nair, since dupilumab showed a significant improvement on asthma control regardless of eosinophil levels, this treatment may be indicated for a wider range of patients than previously thought possible. Also, if new treatment pathways are found, the use of corticosteroids might be avoided.