Helping Canadians with asthma to breathe easier

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The world-renowned Firestone Clinic at St. Joseph’s Healthcare Hamilton is finding new ways to help nearly three million Canadians diagnosed with asthma.

Ground-breaking new treatment options enabled through research at St. Joseph’s Healthcare Hamilton are now being approved by Health Canada and the FDA.

The prevalence of asthma has been increasing over the past 20 years. While the causes of asthma aren’t known, the disease affects almost 15 per cent of children between the ages of four and 11.

In Canada, asthma accounts for approximately 80 per cent of chronic disease cases and is a major cause of hospitalization in children. Approximately 90 per cent of children diagnosed with asthma also have allergies.

A series of clinical trials led by researchers at St. Joseph’s Healthcare Hamilton have validated new medications that improve upon traditional treatments for asthma.

Testing new treatments for severe asthma

A new, antibody-based medication named mepolizumab can replace traditional, steroid-based treatments for a subset of patients with severe asthma, improving control of asthma symptoms without side effects.

Previous research at St. Joseph’s Healthcare Hamilton has identified that a sub-set of patients with severe asthma have an overabundance of particular type of white blood cells (eosinophils) present in their sputum.  These patients often suffer from the most severe asthma symptoms and can only be treated through steroid-based treatments such as high dose prednisone, causing side effects such as mood swings, diabetes, bone loss, skin bruising, cataracts and hypertension.

Subsequent research has successfully evaluated mepolizumab as a new treatment for severe asthma. St. Joseph’s Healthcare Hamilton served as one of the recruiting sites for this global trial, recruiting the maximum number of patients for a single site.

“This is an exciting example of personalized medicine for asthma,” says Dr. Parameswaran Nair, respirologist at St. Joseph’s Healthcare Hamilton, professor at McMaster University and study author. “Our research suggests that by using a simple blood or sputum eosinophil count, we can identify which asthma patients can benefit from this new treatment.  Rather than risking severe side effects through high doses of prednisone, we can precisely target the protein that brings these white blood cells into the lungs.”

In late 2015, mepolizumab was approved for administration in Canada and the United States – providing physicians and respirologists with a new way to treat severe eosinophilic asthma. The technique of quantifying inflammation in sputum, a test pioneered by the late Professor Freddy Hargreave, contributed as much if not more than novel therapies to managing severe airway diseases. St Joseph’s Healthcare Hamilton is the only centre in Canada that offers unrestricted access to this test for patients.

Relieving allergic asthma with antibodies

Another antibody-based treatment developed and successfully tested at the Firestone Clinic at St. Joseph’s Healthcare Hamilton improves quality of life for individuals with mild allergic asthma.

Today, individuals with allergic asthma are typically treated with inhaled corticosteroids or bronchodilators that help to control their asthma when taken regularly. This new medication provides a new treatment option for those with allergic asthma that have issues with inhalers or steroid-based medications.

Named AMG 157, the new medication reduces lung constriction and inflammation by suppressing a protein called thymic stromal lymphopoeitin (TSLP).  By blocking this protein, the antibody both alleviates baseline inflammation and provides resistance to allergens.

“It was known that the epithelial cells which line the airways in the lungs produce a protein called TSLP that causes inflammation,” says Dr. Paul O’Byrne, respirologist at St. Joseph’s Healthcare Hamilton, Chair of Medicine at McMaster University and study author. “Our work, for the first time, proved that these cells continually produce this protein in humans with asthma.”

Multicentre trials led by researchers at St. Joseph’s Healthcare Hamilton evaluated the effectiveness of this antibody-based treatment – establishing proof-of-concept and moving this medication into phase two clinical trials.

Successfully evaluating new antibody-based treatments for asthma enables physicians and respirologists to provide effective treatment to patients without negative side effects of conventional treatment. This has the potential to transform care across Canada and around the world.

Dr. Nair and Dr. O’Byrne continue to work alongside fellow researchers at the Firestone Clinic to improve care for asthma and other pulmonary diseases.