Mount Sinai Researchers Advance a Universal Influenza Virus Vaccine
A vaccine that induces immune responses to a wide spectrum of influenza virus strains and subtypes has produced strong and durable results in early-stage clinical trials in humans, Mount Sinai researchers have found. The universal influenza virus vaccine, which produces antibodies that target the part of the surface protein of the influenza virus known to neutralize diverse influenza strains, was described in a study published today in the journal Nature Medicine. This chimeric hemagglutinin (HA)-based vaccine has the potential to provide long-lived protection with two or three immunizations, eliminating the need for revaccination.
“An influenza virus vaccine that results in broad immunity would likely protect against any emerging influenza virus subtype or strain and would significantly enhance our pandemic preparedness, avoiding future problems with influenza pandemics as we see them now with COVID-19” says Florian Krammer, PhD, Professor of Microbiology at the Icahn School of Medicine at Mount Sinai, and corresponding author of the study. “Our chimeric hemagglutinin vaccine is a major advance over conventional vaccines which are often mismatched to the circulating strains of virus, impacting their effectiveness. In addition, revaccinating individuals annually is a huge and expensive undertaking.”
Seasonal influenza is a major public health concern, triggering as many as 650,000 deaths every year globally, according to the World Health Organization. In addition, influenza pandemics, similar to the current COVID-19 outbreak, occur at irregular intervals and can claim millions of lives. The most devastating example is the H1N1 pandemic of 1918, which caused approximately 40 million deaths. Influenza virus vaccines -- the best preventive weapon in the public health arsenal against seasonal influenza -- contain three or four strains of the influenza virus that respond to the viruses circulating in the human population. Their inherent weakness, however, is that vaccine strains in the annual formulations are based on global health surveillance and predictions that are often out of sync with the strains that actually circulate. The situation is compounded in the case of emerging pandemic viruses, since these outbreaks cannot be predicted and emerge suddenly, requiring newly matched vaccines to be generated. This process requires at least six months, leaving large portions of the population vulnerable.
The chimeric HA vaccine seeks to correct this uncertainty by targeting a different part of the hemagglutinin protein, the major surface glycoprotein of the influenza virus that binds to host cell receptors. Conventional vaccines induce neutralizing antibodies that target the distal part of the hemagglutinin, known as the globular head domain. “Unfortunately, the virus is able to escape neutralization by mutating this part of hemagglutinin through a process known as antigenic drift,” explains Peter Palese, PhD, Professor of Microbiology and Chair of the Department of Microbiology at Icahn School of Medicine at Mount Sinai, and co-author of the study. “This genetic change, or shift, in the virus results in immunity to only specific strains of the influenza virus, requiring frequent re-formulation and re-administration of seasonal vaccines. Our chimeric HA vaccine, by contrast, is directed at the proximal part of the HA protein -- the stalk domain -- which has been shown to broadly neutralize diverse influenza virus strains in both animal models and humans.”
A vaccine construct based on the hemagglutinin stalk domain has been a major focus of the research community. “The beauty part of this vaccine is that it’s not only broad, but multifunctional with stalk-specific antibodies that can neutralize many kinds of influenza viruses,” emphasizes Dr. Adolfo García-Sastre, Director of the Global Health and Emerging Pathogens Institute and Professor of Microbiology at the Icahn School of Medicine at Mount Sinai and also co-author of the study. “This universal vaccine could be particularly beneficial to low and middle income countries that don’t have the resources or the logistics to vaccinate their populations each year against influenza.”
Mount Sinai’s Phase 1 clinical trial evaluated the safety and immunogenicity of the vaccine in 65 participants in the U.S., and was found to produce a strong immune response that endured for at least 18 months following vaccination. “This phase of our clinical work significantly advances our understanding of the immune response in terms of its longevity,” says Dr. Krammer, “and leaves us greatly encouraged about future progress for this potentially breakthrough vaccine.”
Collaborative efforts between Mount Sinai, PATH, GSK, the University of Chicago Pritzker School of Medicine, Cincinnati Children's Hospital Medical Center and Duke University School of Medicine in North Carolina contributed to the successful testing of this vaccine candidate.
The study was funded in part by the Bill and Melinda Gates Foundation and the NIH. Basic research leading to the design of the vaccine were initially funded by NIAID’s Centers of Excellence for Influenza Research and Surveillance (CEIRS) and analysis of the immune response at later stages was also funded through NIAID’s Collaborative Influenza Vaccine Innovation Centers (CIVIC).
About the Mount Sinai Health System
Mount Sinai Health System is one of the largest academic medical systems in the New York metro area, with 48,000 employees working across eight hospitals, more than 400 outpatient practices, more than 600 research and clinical labs, a school of nursing, and a leading school of medicine and graduate education. Mount Sinai advances health for all people, everywhere, by taking on the most complex health care challenges of our time—discovering and applying new scientific learning and knowledge; developing safer, more effective treatments; educating the next generation of medical leaders and innovators; and supporting local communities by delivering high-quality care to all who need it.
Through the integration of its hospitals, labs, and schools, Mount Sinai offers comprehensive health care solutions from birth through geriatrics, leveraging innovative approaches such as artificial intelligence and informatics while keeping patients’ medical and emotional needs at the center of all treatment. The Health System includes approximately 9,000 primary and specialty care physicians and 11 free-standing joint-venture centers throughout the five boroughs of New York City, Westchester, Long Island, and Florida. Hospitals within the System are consistently ranked by Newsweek’s® “The World’s Best Smart Hospitals, Best in State Hospitals, World Best Hospitals and Best Specialty Hospitals” and by U.S. News & World Report's® “Best Hospitals” and “Best Children’s Hospitals.” The Mount Sinai Hospital is on the U.S. News & World Report® “Best Hospitals” Honor Roll for 2024-2025.
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