TORONTO — Health Canada has approved Sanofi Pasteur’s Fluzone High-Dose influenza vaccine developed for adults age 65 and older.

A trivalent vaccine, Fluzone High-Dose contains four times the amount of hemagglutinin (HA) per strain versus a standard dose vaccine and is administered as a single, 0.5 ml intramuscular injection. The higher-dose flu shot, which already has been approved by the U.S. Food and Drug Administration, is intended to help lower flu rates among seniors, who are at increased risk for influenza and its complications.

“Public health authorities have long recognized a large unmet need among seniors as it relates to influenza and have been asking for the development of more effective influenza vaccines for this age group, who are more vulnerable to the consequences of the flu,” stated Dion Neame, head of scientific and medical affairs at Sanofi Pasteur Ltd. “As a company, we invested in a large efficacy trial which has provided robust evidence that addresses a public health priority to help reduce influenza illness among adults 65 years and older. Fluzone High-Dose vaccine has been available in the U.S. since 2009, and we look forward to bringing this innovation to Canada this fall.”

Sanofi Pasteur noted that as the immune system declines with age, older adults don’t respond to standard-dose flu vaccines as well as younger adults do. Fluzone High-Dose was developed to address the need for an enhanced immune response in seniors.

“There is now strong data which demonstrates that this high-dose vaccine provides those 65 years of age and older with enhanced protection against influenza,” commented Janet McElhaney, geriatrician and medical lead for seniors care and Health Sciences North Volunteer Association Chair in Healthy Aging and scientific director for the Advanced Medical Research Institute of Canada. “This is the first randomized trial that has shown not only an increase in efficacy, but has also translated into clinically important outcomes.”

According to research cited by Sanofi Pasteur, adults age 65 and older represent 15% of Canada’s but account for 70% of all flu-related hospitalizations and 90% flu-related deaths. And while most people can recover from flu in as few as seven days, it may take longer for seniors because they are at risk of developing more severe complications, including pneumonia, or worsening underlying medical conditions.