After the incredible success of the COVID-19 mRNA vaccines, scientists now turn their attention to influenza. Both Moderna and Pfizer—makers of the first vaccines to earn U.S. Food and Drug Administration (FDA) approval using the mRNA technology—are studying whether subbing in the influenza virus’ genetic material in that platform will prove equally fruitful.
Pfizer revealed that its first volunteers received a dose of its mRNA influenza shot on September 14. Phase 3 will include more than 25,000 adult Americans ages 18-64 who will randomly be assigned either to get the experimental vaccine, or the placebo. Moderna’s late-stage clinical trial for an mRNA-based flu vaccine, which targets the same strains of influenza that will be in circulation this winter and fall, was announced by Moderna. Moderna’s study will involve 6,000 adults in the U.S. and other countries in the southern hemisphere, which experiences its flu season several months before the U.S. They are both in the same stage of their trials. However, neither company has yet to provide a timeline or if they expect positive results when they can submit a request for FDA approval.
Public health experts are hoping it won’t be long, however. The advantage of the mRNA platform is that it’s flexible and generalizable. In theory, scientists need only to change the genetic material or mRNA sequences from one virus to the next. It’s a matter of figuring out which specific genes will activate the immune system the best—and that’s where researchers have decades of experience with influenza that they didn’t have with SARS-CoV-2.
Continue reading: We Have the First COVID-19 Vaccines Thanks to mRNA Technology. This Technology Could also Reignite the Drug Industry
Each company is focusing on the four flu strains identified by the World Health Organization in February. These flu strains are most likely to be in circulation during the 2022-2023 influenza season in northern hemisphere. Moderna and Pfizer both showed that Moderna’s early flu shots were safe. They are now conducting late-stage research to see if the vaccine is effective in protecting against influenza. The current vaccines are based on decades-old technology, and involve growing influenza virus in chicken eggs. They have been relatively effective. WHO experts are able to accurately match flu strains and vaccine strains, which protects people from serious illnesses between 40%-60%. In years when the match isn’t as tight, the shot’s effectiveness goes down to about 20%-30%.
This mismatch should be eliminated by mRNA vaccines. Manufacturers can produce shots with new sequences of genetic DNA in as little as three months, thanks to the flexibility of the technology. Scientists could produce new mRNA flu vaccines if there is a mismatch in a season..This could help reduce influenza-related deaths and hospitalizations, both of which are still high. Each year, the virus can cause up to 700,000. Hospitalizations and over 52,000 deaths in the United States.
Although an mRNA flu shot is a significant advance in vaccine technology it may not be the best way to prevent respiratory illnesses. Moderna has also been conducting a trial to test combination vaccines which would protect against influenza and SARS-CoV-2 in one shot.
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