FDA poised to decide mRNA flu

The U.S. Food and Drug Administration approved Moderna’s mFLUSIVA on Wednesday, clearing the first influenza vaccine made with messenger RNA technology for adults 50 and older, the company said. The decision came on the Aug. 5 Prescription Drug User Fee Act deadline that Moderna disclosed earlier this year after the agency agreed to review the shot. (newswire.com) Moderna said it expects supply at select retailers in the coming weeks ahead of the 2026-27 respiratory virus season. The product gives Moderna a flu vaccine on the market after years of trying to extend its mRNA platform beyond COVID-19. ### Which vaccine did the FDA clear, and for whom? mFLUSIVA, also known as mRNA-1010, was approved for adults 50 years and older, Moderna said on Aug. 6. (newswire.com) The company said the FDA granted standard approval for adults 50 through 64 and accelerated approval for adults 65 and older. STAT reported the vaccine will be marketed as mFlusiva and described it as the first licensed flu shot made with mRNA technology. August 5 was the FDA’s target action date after the agency accepted a revised biologics license application in February. Moderna had said at that time that it proposed an age-split regulatory path after receiving a prior refusal-to-file letter, with a post-marketing study in older adults. (newswire.com) ### Why was this decision in doubt earlier this year? February brought an unusual setback when FDA officials initially declined to review the application, according to STAT and ABC News. STAT reported that Vinay Prasad, then the FDA’s top biologics official, issued the refusal-to-file decision after overturning career staff, and that the decision was reversed about a week later. (newswire.com) ABC said the agency later agreed to review the shot after Moderna committed to another study once the vaccine reached the market. June 18 gave Moderna a public endorsement when the FDA’s Vaccines and Related Biological Products Advisory Committee voted 9-0 that the vaccine’s benefits outweighed its risks in adults 50 to 64 and separately 9-0 for adults 65 and older, according to Moderna and FDA meeting materials. (drugs.com) ### What evidence did Moderna use to win approval? Moderna said the approval in adults 50 through 64 was based on a randomized Phase 3 trial that enrolled 40,805 adults 50 and older across 11 countries. The company said the trial compared mFLUSIVA with a standard-dose influenza vaccine and measured relative vaccine efficacy against RT-PCR-confirmed influenza-like illness caused by influenza A or B. (statnews.com) ABC News reported that, in adults 50 to 64, the mRNA shot produced 27% fewer confirmed flu cases than the current standard vaccine. Moderna said the safety profile was acceptable and that no new safety concerns were identified, while ABC reported that side effects were more common with mFLUSIVA but were mostly mild and lasted two days or less. (newswire.com) ### Why does the older-adult approval come with extra conditions? Adults 65 and older received an accelerated approval, not a full approval, Moderna said. The company said that decision was based on an immunogenicity study of 2,992 U.S. participants age 65 and older and supported by descriptive analyses from the larger Phase 3 trial. (newswire.com) Moderna said confirmation of clinical benefit in that age group will come from a postmarketing trial. STAT reported Moderna agreed to collect more effectiveness data comparing mFlusiva with the high-dose or adjuvanted vaccines already recommended for older adults. ABC said Moderna plans to gather data this winter and submit it to the FDA to support continued approval in that population. (abcnews.com) ### Why have vaccine developers been chasing an mRNA flu shot? Most flu vaccines are still made in eggs, and some are made in cells, STAT reported. STAT said those production methods require a long lead time, forcing strain selection months before the season and raising the risk of a mismatch with circulating viruses. The outlet reported that mRNA vaccines can be produced faster, which could allow strain updates closer to flu season and could help in a future influenza pandemic. (newswire.com) Stéphane Bancel, Moderna’s chief executive, said in a company statement that “flu remains a significant public health challenge” and called mFLUSIVA “an important new option for America’s seniors.” Moderna said the product is its fourth FDA-approved product and fifth approved product globally. (statnews.com) August and the coming winter are the next milestones. Moderna said doses should be available at select retailers in the coming weeks for the 2026-27 season, and the company has committed to a postmarketing study in adults 65 and older to confirm clinical benefit. (newswire.com) (statnews.com)