FDA Reverses Stance on Moderna’s Flu Vaccine Review After Quick Talks

The U.S. Food and Drug Administration has agreed to review Moderna's mRNA-based flu vaccine for adults aged 50 and older, just one week after sending the company a refusal letter. Moderna made changes to its application after a meeting with agency officials, setting up a possible approval decision by August 5.

Background

Moderna has been working on its flu vaccine, called mRNA-1010, for several years. The shot uses the same mRNA technology that powered the company's COVID-19 vaccine. Company scientists tested it in large trials with thousands of adults to check safety and how well it works against the flu.

Last week, on February 10, Moderna shared that the FDA would not look at its original application. The agency sent a refusal-to-file letter. The main issue was the choice of comparison vaccine in the studies. For older adults, the FDA wanted a stronger flu shot as the benchmark, one that health experts already recommend for people 65 and up.

Moderna pointed out that the FDA had okayed the study design earlier. The company also shared extra data from tests where it did use a high-dose flu vaccine in seniors. Even so, the FDA stuck to its position at first.

This back-and-forth happened amid closer looks at vaccines from top health officials. The dispute played out partly in public, with Moderna posting the redacted refusal letter on its website. Such quick public pushback between a drug company and the FDA is rare.

Key Details

Moderna met with FDA staff in what is called a Type A meeting. These meetings happen fast when there is a big roadblock like a refusal letter. The talks led to a deal on a new plan.

The New Approval Paths

Under the revised filing, Moderna wants full approval for adults 50 to 64 years old. For those 65 and older, it seeks accelerated approval. That means the vaccine could reach the market faster for seniors, but Moderna must run another study after launch to confirm it works well in that group.

The trials behind this include P303, a safety and immune response study in adults 18 and up. In one part, researchers compared mRNA-1010 to a standard flu shot. In seniors, they used a high-dose version, which showed good results for Moderna's vaccine.

Another trial, P304, looked at how well the vaccine prevents flu in people 50 and older. It also used a standard-dose flu shot as the control.

The big Glow trial enrolled over 22,000 adults 50 and older from late 2022 to early 2024. People got one shot and were tracked for about 13 months through visits and check-ins.

The FDA set August 5 as the target date to act on the application. If all goes well, mRNA-1010 could hit shelves for the 2026-27 flu season. Moderna has also filed in Europe, Canada, and Australia, with more countries to follow.

“We appreciate the FDA’s engagement in a constructive Type A meeting and its agreement to advance our application for review,” said Stéphane Bancel, chief executive officer of Moderna. “Pending FDA approval, we look forward to making our flu vaccine available later this year so that America’s seniors have access to a new option to protect themselves against flu.”

Moderna's stock jumped more than 7% in early trading after the news. Shares hit around $47.

What This Means

This turnaround keeps Moderna on track to launch its first standalone flu vaccine. The company sees flu shots as a big part of its future sales. Analysts expect mRNA-1010 to bring in billions of dollars over time, along with a combo flu-COVID vaccine in the works.

Moderna aims to break even by 2028. The refusal letter had raised doubts about that goal, forcing some analysts to adjust their forecasts. Now, with the review moving forward, those plans look solid again.

For patients, especially older adults, this opens the door to a new flu vaccine option. Current shots are mostly inactivated virus or protein-based. An mRNA version could offer stronger protection or easier updates each year as flu strains change.

The split approval approach shows how companies and regulators can compromise. Full approval for mid-age adults relies on existing trial data. Accelerated approval for seniors speeds things up but adds checks later.

Health groups like the CDC's Advisory Committee on Immunization Practices push high-dose or boosted flu shots for those 65 and up. Moderna's data against those comparators helped sway the FDA.

No safety issues came up in the refusal or talks. Trials showed the vaccine was safe, with immune responses matching or beating standard shots.

Moderna plans to file for the combo vaccine next, once this one advances. Success here could speed that up too.

The flu hits millions each year in the U.S., sending many to hospitals, mostly seniors. A new tool like mRNA-1010 might cut those numbers if it proves effective in real-world use.

Investors watched closely as Moderna shifts from COVID reliance to everyday vaccines like flu. This step boosts confidence in that pivot.

Regulators continue to review mRNA tech carefully. Past approvals set the stage, but each new use gets fresh scrutiny to ensure benefits outweigh risks.