Moderna Inc.’s influenza vaccine yielded mixed results in a final-stage trial, raising questions about the drugmaker’s plan to seek US approval for a flu shot based on its messenger RNA technology as soon as this year.
(Bloomberg) — Moderna Inc.’s influenza vaccine yielded mixed results in a final-stage trial, raising questions about the drugmaker’s plan to seek US approval for a flu shot based on its messenger RNA technology as soon as this year.
In a trial of over 6,000 adults 18 and older, Moderna’s mRNA-1010 flu shot produced an immune response against influenza A, the most common type of the virus, that was at least as good as an existing vaccine, Moderna said Thursday in a statement. Against influenza B, Moderna’s shot failed to prove it was equivalent to the existing vaccine. The study looked only at immune responses as well as safety, and didn’t directly examine the shot’s ability to prevent disease.
Shares of Moderna slid 5.4% after US markets closed Thursday. They had lost 4.1% this year in regular trading.
Moderna is betting on the flu shot to help expand its mRNA vaccine franchise, hoping to combine it with a Covid-19 booster that could be administered annually to people at high risk for respiratory illness. The company is conducting a second final-stage trial of the flu vaccine in the US and other Northern Hemisphere countries that looks at the shot’s ability to protect adults 50 years and older. That study could produce initial results by the end of this quarter.
“While we did not achieve non-inferiority for the influenza B strains which are more frequent in younger populations, we have already updated the vaccine,” Moderna President Stephen Hoge said in the statement. That could improve immune responses, he said.
Moderna didn’t release details about the immune results from the just-completed study. But the company could still seek full approval for its flu vaccine this year if the results from the large Northern Hemisphere trial are positive, Hoge said in an interview.
“The basis of full approval was always going to be the parallel pivotal study” examining efficacy, he said. In that trial, which is ongoing, nearly all the cases so far are influenza A.
In the Southern Hemisphere trial, 70% of people who received Moderna’s vaccine experienced common side effects such as pain, swelling, headache or fatigue, compared to 48% of people who got an existing vaccine, Moderna said.
Moderna’s shot produced higher levels of protective antibodies against the H3N2 strain than an existing vaccine, the company said in a statement Thursday. Against another strain, H1N1, Moderna’s shot was superior on one immune measure to the existing vaccine and similar on another measure.
(Updates with stock price in third paragraph)
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