Health Canada has granted approval for the use of a new vaccine designed to combat the respiratory syncytial virus (RSV), focusing on safeguarding two particularly vulnerable demographics: newborns, who would acquire antibodies through maternal immunization, and Canadians aged 60 and above.
The bivalent vaccine, named Abrysvo and developed by Pfizer Canada, is aimed at preventing lower respiratory tract disease caused by RSV. This marks the first RSV vaccine in Canada sanctioned for use during pregnancy, providing protection for infants from birth to six months of age. Additionally, it is the second vaccine approved for individuals aged 60 and over. The U.S. Food and Drug Administration had previously granted approval for the vaccine for these two groups in 2023.
RSV is a common and highly contagious respiratory virus known to cause cold-like symptoms. However, for more vulnerable populations, such as infants, older adults, or those with respiratory or cardiac conditions, RSV can lead to severe illnesses like bronchiolitis or pneumonia, often requiring hospitalization.
The Pfizer vaccine, administered as a single shot during the third trimester of pregnancy (from 32 through 36 weeks), produces antibodies that are transmitted from parent to infant. This method of immunization during pregnancy is already recommended for various diseases, including COVID-19, influenza, and pertussis. For older adults, the vaccine is also administered as a single shot.
Health Canada had previously approved an RSV vaccine for seniors from GSK in August, and in spring 2023, an antibody drug called nirsevimab was approved to protect newborns and infants from severe RSV-related illnesses.
RSV is a leading cause of hospitalization in infants and young children. Dr. Jesse Papenburg, a pediatric infectious diseases specialist at the Montreal Children’s Hospital, emphasized the critical period when infants encounter RSV for the first time, as it poses a significant risk of the virus reaching the lungs.
With the availability of a vaccine for pregnant individuals and an antibody drug for newborns, the potential to “substantially reduce the burden of RSV in Canadian children” exists, according to Dr. Papenburg.
Following Health Canada’s approval, federal officials will collaborate with provincial and territorial counterparts to assess interest, potential demand, and timelines for integrating these products into RSV vaccination programs. Dr. Papenburg anticipates the products to be available for use in Canada during the winter of 2024-25.
Considering factors like availability and accessibility, he highlighted the importance of economic analyses to inform decisions about the implementation of universal vaccination programs, mindful of the impact on the healthcare system.
Amid the current cold and flu season, the rising cases of RSV, influenza, COVID-19, and other viruses have strained emergency rooms nationwide. Dr. Fatima Kakkar, a pediatric infectious diseases specialist, stressed the urgency of widely distributing the new tools to combat RSV, emphasizing that delays of one or two years are not acceptable.
Pfizer Canada’s spokesperson stated that the company is actively assessing the availability of its RSV vaccine, consulting with various stakeholders on cost considerations and devising strategies to bring it to Canadians as swiftly as possible.
