A groundbreaking study conducted by Oregon Health & Science University (OHSU) proposes a promising strategy for creating a universal influenza vaccine—a “one and done” vaccine that offers lifelong immunity against the constantly changing virus.
Published in Nature Communications, the study tested an innovative vaccine platform developed by OHSU against the virus most likely to cause the next pandemic. The vaccine elicited a strong immune response in nonhuman primates exposed to the avian H5N1 influenza virus. Remarkably, the primates were vaccinated against the 1918 influenza virus, which caused a global pandemic.
“This is thrilling because usually, basic science research progresses slowly, potentially leading to something significant in 20 years,” said Jonah Sacha, Ph.D., the study’s senior author and professor at OHSU’s Oregon National Primate Research Center. “However, this could become a vaccine in five years or less.”
The study revealed that six out of 11 vaccinated nonhuman primates survived exposure to H5N1, one of today’s deadliest viruses. In comparison, all six unvaccinated primates succumbed to the disease. Sacha is optimistic about the platform’s potential to combat other evolving viruses, including SARS-CoV-2.
“For pandemic-potential viruses, having a tool like this is crucial. While we aimed to test influenza, the next threat could be anything,” Sacha explained.
Douglas Reed, Ph.D., a co-author from the University of Pittsburgh, agreed: “If a deadly virus like H5N1 triggers a pandemic in humans, we need to quickly validate and deploy a new vaccine.”
This approach builds on a vaccine platform OHSU scientists previously developed for HIV and tuberculosis, which is currently in clinical trials for HIV. The method involves inserting small parts of target pathogens into the common herpes virus cytomegalovirus (CMV), which most people encounter in their lifetime without severe symptoms. CMV acts as a vector to stimulate an immune response from the body’s T cells.
Unlike typical vaccines that target the virus’s evolving exterior proteins, this method prompts T cells to attack the internal structural proteins of the virus, which remain relatively unchanged over time. This creates a stable target for T cells to recognize and eliminate infected cells, regardless of the virus’s mutations.
“The challenge with influenza is that it’s always evolving, similar to SARS-CoV-2. We’re constantly trying to catch up with the virus’s latest variant,” Sacha noted.
To validate their theory, researchers developed a CMV-based vaccine using the 1918 influenza virus. They then exposed vaccinated nonhuman primates to aerosolized avian H5N1 influenza virus in a secure biosafety level 3 lab at the University of Pittsburgh. Astonishingly, six of the vaccinated primates survived, underscoring the internal protein’s preservation over a century of virus evolution.
“It succeeded because the virus’s internal protein remained well conserved, even after almost 100 years,” Sacha said.
This finding suggests the potential for a protective H5N1 vaccine in humans. “Inhaling aerosolized H5N1 influenza virus can lead to severe respiratory issues,” said co-senior author Simon Barratt-Boyes, Ph.D., from the University of Pittsburgh. “The vaccine-induced immunity was sufficient to reduce infection and lung damage, safeguarding the monkeys from this serious infection.”
The study indicates that by updating virus templates, CMV vaccines might generate long-lasting immune responses against various new variants. “Within five to 10 years, a single-shot flu vaccine seems feasible,” Sacha asserted.
The CMV platform developed by OHSU has also progressed to clinical trials for HIV prevention and shows potential for targeting specific cancer cells, according to recent publications. The HIV clinical trial is led by Vir Biotechnology, which licensed the platform from OHSU.
“We are witnessing a significant shift in how we approach infectious diseases,” Sacha added. “There’s no doubt we are entering the next era of disease treatment and prevention.”
As reported by pharmabiz.com, the study involved collaborations with the Tulane National Primate Research Center, the University of Pittsburgh, the University of Washington, and the Washington National Primate Research Center at UW.