American company Moderna on Thursday announced mixed interim results for its flu vaccine using messenger RNA technology, the same as for its Covid-19 vaccine.
These clinical trial results (phase 3) do not yet reveal the efficacy of the vaccine, but provide data on the immune response triggered by an injection.
For the most prevalent influenza A subtypes known as H1N1 and H3N2, the immune response elicited by Moderna's vaccine has been shown to be superior to other vaccines already licensed, but not against the Yamagata and Victoria lineages of the influenza B.
In electronic trading after the close of Wall Street, Moderna shares lost nearly 6%.
The trials were conducted on more than 6,000 adults in Argentina, Australia, Colombia, Panama and the Philippines.
Participants received either a dose of Moderna's vaccine (mRNA-1010) or a previously licensed vaccine.
“Although we did not achieve non-inferiority for influenza B strains, which are more common in young people, we have already updated the vaccine,” said Stephen Hoge, president of the company, in a press release. Moderna. “We believe this could improve the immune response against influenza B, and will seek to quickly confirm these improvements in an upcoming clinical trial, thanks to the agility of our mRNA platform.
The vaccine was generally well tolerated, according to the company.
Current flu vaccines use inactivated viruses that have lost their ability to cause infection, while eliciting an immune system response.
But the strain used must be selected months in advance, and their effectiveness is between 40 and 60%.
Messenger RNA technology works differently and should notably allow the vaccine to be developed and adapted more quickly.
The World Organization of Health estimates that influenza is responsible for approximately 3 to 5 million cases of serious illness each year, and 290,000 to 650,000 deaths. It particularly affects the elderly.
Moderna currently has only one product on the market, its vaccine against Covid-19.
The company is also working on combination vaccines, both against influenza, Covid-19, but also RSV (respiratory syncytial virus).
The American pharmaceutical giant Pfizer and its German partner BioNTech have also launched trials for a combined messenger RNA vaccine against influenza and Covid-19.