Moderna Poised to Seek Flu Shot Approval After Trial Results

Moderna Inc. said a reformulated version of its messenger-RNA based flu shot met its primary goals in a final-stage trial — a result that could pave the way for the company to seek regulatory approval for the influenza vaccine.

(Bloomberg) — Moderna Inc. said a reformulated version of its messenger-RNA based flu shot met its primary goals in a final-stage trial — a result that could pave the way for the company to seek regulatory approval for the influenza vaccine.

In a trial on over 2,400 adults, the reformulated shot produced a stronger immune response against all four strains of the influenza virus than a traditional flu vaccine, the company said in a statement Wednesday. Side effects were similar to previous trials of the vaccine. The study looked at antibody levels against the flu and didn’t directly assess efficacy in preventing disease symptoms. 

Moderna shares jumped as much as 9.2% in New York trading. The stock had declined 41% this year through Tuesday’s close.

“Our goal would be to file very quickly” for accelerated approval in the US, Moderna president Stephen Hoge said in an interview, without offering a specific timeline. Depending on how much additional follow-up data regulators need, Moderna’s shot could be on the market as soon as next year’s fall-winter flu season, he said.

The flu data is in line with expectations and it’s likely Moderna files for regulatory approval by year’s end, analysts from Jefferies said in a note. 

Developing an influenza vaccine is important for Moderna as it seeks new sources of revenue as sales for Covid-19 shots fade amid pandemic fatigue. Moderna’s share decline this year adds urgency to its efforts.  

The company is working on combination vaccines against both flu and Covid — and potentially other respiratory diseases that could reduce the number of shots needed for broad protection. In a few years, these combos should produce large annual sales, Moderna Chief Executive Officer Stephane Bancel said in an interview Wednesday on Bloomberg TV.  

“This is going to be a $15-plus billion annual sales franchise forever,” Bancel said. Analysts expect Moderna’s revenue to fall to about $7 billion this year.


Moderna’s mRNA flu shot was reformulated earlier this year after an initial large trial showed mixed results compared to existing vaccines. The original formulation performed well against influenza A, the most common type of flu, but fell short of showing it was as good as traditional vaccines at provoking an immune response against influenza B, a less common type. 

The new results, if confirmed, indicate the reformulation worked. The company didn’t provide details of the results, which haven’t yet been published in a scientific journal. An accelerated approval would allow the shot to be approved in the US based on the current findings while Moderna conducts a larger study to confirm that the vaccine prevents disease symptoms. 

As sales for Covid shots wane, Moderna is working to expand its product portfolio and show that its technology will work against other diseases, including various respiratory viruses and cancer. Moderna said it expects combination vaccines to be available as soon as 2025.

“Frankly, the goal here is to just get the flu vaccine on the market and be able to combine it with Covid/RSV in a combo vaccine,” according to the note from Jefferies.

RSV Shot

Besides flu and Covid, Moderna is also working on an mRNA vaccine for another virus that affects older adults, called respiratory syncytial virus (RSV). Moderna said it has completed its US regulatory filing for its vaccine for RSV in older adults and expects a decision by April 2024. 

The company is behind in this vaccine race, however. Rivals Pfizer Inc. and GSK introduced adult RSV vaccines that use older technology to the US this year.  

Another potential application for Moderna’s mRNA technology is cancer vaccines. The Cambridge, Massachusetts-based company developed a promising personalized cancer vaccine that is now in a final-stage trial for melanoma with its partner, Merck & Co. Moderna said it plans to begin a second phase 3 trial of the vaccine in lung cancer with Merck later this year. 

And earlier this week, it said that it would pay as much as $1.8 billion to German biotechnology company Immatics NV in a broad-ranging, multi-year collaboration to develop cancer therapies using mRNA and other technologies.

Moderna will meet with investors Wednesday to update them on its products in testing, offering more details about its flu shot trial as well as mRNA-based drugs being tested for rare diseases. 

Hoge said he remains confident that the mRNA technology will work across a wide range of ailments. “This platform is really starting to fire on all cylinders,” he said. “You have to ignore a lot of data to call this just a Covid company.”

–With assistance from Madison Muller and Cailley LaPara.

(Updates with comments from CEO in seventh paragraph.)

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