An experimental vaccine offers broad protection against all 20 known influenza A and B virus subtypes in initial tests in mice and ferrets, according to a U.S. study released Thursday, which could potentially lead to future infections. could pave the way for universal influenza vaccination that could help prevent pandemics.
The two-dose vaccine employs the same messenger RNA (mRNA) technology used in the COVID-19 shot developed by Pfizer PFE.N, BioNTech 22UAy.DE and Moderna MRNA.O. It delivers small lipid particles containing mRNA instructions for the cell to make a replica of the so-called hemagglutinin protein that appears on the surface of the influenza virus.
A universal vaccine doesn’t mean the end of the flu season, but it does replace the guess work of developing an annual vaccination months before each flu season.
“The idea here is to make a vaccine that gives people a baseline level of immune memory against different flu strains, so that when the next flu pandemic hits, they’ll get much less sick and die. study leader Scott Hensley of the Perelman School. The University of Pennsylvania School of Medicine said in a statement.
Unlike standard influenza vaccines, which deliver one or two versions of hemagglutinin, the experimental vaccine contains a vaccine that hopefully allows the immune system to recognize influenza viruses it may encounter in the future. , which includes 20 different types.
In laboratory experiments, the immune system of vaccinated animals recognized the hemagglutinin protein and protected against 18 influenza A strains and 2 influenza B strains. journal science.
The vaccine reduced signs of illness and protected ferrets from death, even if they were exposed to another type of flu not included in the vaccine, the researchers said.
Moderna and Pfizer both have mRNA flu vaccines in late-stage human trials, and GSK GSK.L and partner CureVac 5CV.DE are testing mRNA flu vaccines in early-stage safety trials in humans. These vaccines are designed to protect against only the four most recently circulating influenza strains, but could theoretically change each year.
Universal flu vaccines, even if successful in human trials, do not necessarily prevent infection.The goal is to provide lasting protection against severe illness and death, Hensley said. .
Alison Kelvin and Darryl Falzarano, of the University of Saskatchewan, Canada, are left with questions about how to determine vaccine efficacy and potential regulatory requirements against future viruses that are not currently circulating.
The promising results of the new vaccine “suggest its ability to protect against all subtypes of the influenza virus, but we won’t be sure until clinical trials in volunteers,” said Mount Global Health and Emerging Pathogens. said Adolfo Garcia Sastrem, Director of the Institute. Sinai Hospital in New York said in a statement.
Reporting by Nancy Rapid. Edited by Christine Soares and Bill Berkrot