Moderna Inc. shares lost the most since December after its influenza vaccine yielded mixed results in a final-stage trial, raising questions about the drugmaker’s plan to seek US approval for the messenger RNA-based shot as soon as this year.
(Bloomberg) — Moderna Inc. shares lost the most since December after its influenza vaccine yielded mixed results in a final-stage trial, raising questions about the drugmaker’s plan to seek US approval for the messenger RNA-based shot as soon as this year.
In a trial of over 6,000 adults 18 and older, Moderna’s experimental mRNA-1010 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, according to a statement Thursday after US markets closed. Against influenza B, Moderna’s shot failed to prove it was equivalent to the available vaccine. The study looked only at immune responses and safety, and didn’t directly examine the shot’s ability to prevent disease. Shares of Moderna fell as much as 5.6% Friday at the New York market open, the most intraday since Dec. 27.
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. Now, it will likely face concerns about whether it can secure approval for a vaccine that shows efficacy only against influenza A, JPMorgan Securities analyst Jessica Fye wrote in a note to clients. The results also raise questions on whether an mRNA vaccine can beat the performance of existing shots that use more traditional approaches, Bloomberg Intelligence analyst Sam Fazeli said in a note.
In the 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.
“Only significantly superior efficacy results would justify use of mRNA-1010 due to its challenging safety and tolerability profile, given the large number of available alternatives,” SVB Securities analyst Mani Foroohar said in a note.
Second Trial
Moderna is conducting a second final-stage trial of the flu vaccine in the US and other Northern Hemisphere countries looking at protection of adults 50 years and older. That study could produce initial results by the end of this quarter.
“The basis of full approval was always going to be the parallel pivotal study” examining efficacy, Moderna President Stephen Hoge said in an interview. In that ongoing trial, nearly all the cases so far are influenza A. The company could still seek approval for its flu vaccine this year if results from the study are positive, Hoge said.
Moderna didn’t release details about the immune results from the just-completed study in the Southern Hemisphere. Moderna’s shot produced higher levels of protective antibodies against the H3N2 strain than an existing vaccine, the company said. Against another strain, H1N1, Moderna’s shot was superior on one immune measure to the existing vaccine and similar on another measure.
The company has already updated the shot, which could improve immune response to influenza B, Hoge said in the company statement. Updating the shot doesn’t necessarily mean the issues with influenza B will be fixed, Fazeli said.
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