US FDA declines Moderna flu vaccine review amid vaccine guidance rollback | Health News
FDA Declines to Review Moderna’s Flu Vaccine Application Amid Guideline Rollbacks
The U.S. Food and Drug Administration (FDA) has declined to review Moderna’s application for approval of its flu vaccine, sparking concerns over recent changes to established vaccine guidelines.
In a letter addressed to Moderna, the FDA questioned the Massachusetts-based company’s justification for its mRNA-1010 vaccine, which has been on the market, and declined to compare it to a standard seasonal flu vaccine. The FDA cited insufficient data as the basis for its decision, stating that the application lacked “adequate and well-controlled” studies. Moderna reported that the agency indicated the flu vaccine “does not reflect the best-available standard of care.”
Moderna’s CEO, Stéphane Bancel, responded by emphasizing that the letter did not raise any safety or efficacy issues regarding the product.
Experts have expressed concern over the lack of clarity in the review process. Bruce Y. Lee, a professor at the CUNY Graduate School of Public Health and Health Policy, stated, “If there are elements requiring scrutiny, a review process can address them. Without that guidance, it becomes challenging for a company submitting materials to know how to proceed.”
Last year, Moderna announced that its mRNA-1010 vaccine demonstrated a 26.6% greater efficacy compared to an approved annual flu vaccine from GlaxoSmithKline.
“This should not be controversial,” Bancel remarked, referring to the desire for a thorough review process that utilizes an FDA-approved vaccine as a comparator in studies previously discussed with the Center for Biologics Evaluation and Research (CBER).
Regarding next steps, William Soliman, CEO of the Accreditation Council for Medical Affairs, indicated that Moderna would likely need to conduct further studies to address the FDA’s concerns. “Typically, they would provide additional analysis or modify the study design and resubmit for review,” Soliman stated.
In 2025, Moderna withdrew its application for a combined flu and COVID vaccine pending further efficacy data from a late-stage trial of its influenza vaccine. The vaccine is currently under review in the European Union, Canada, and Australia, with potential approvals anticipated in late 2026 to early 2027.
The FDA’s decision has prompted discussions around potential political influences affecting its regulatory processes. Concerns have been raised regarding whether the rejection was based on scientific merit or political motivations. Lee noted, “Many policies have been rolling back vaccine guidelines previously supported by science, raising questions about a wider trend.”
Reports from Stat News suggested that agency scientists, including David Kaslow, head of the FDA’s vaccine office, were prepared to review the application but faced opposition from FDA Commissioner Vinay Prasad, a claim the FDA has disputed. The Department of Health and Human Services (HHS) did not respond to requests for comment.
In August, HHS announced plans to reduce mRNA vaccine development. HHS Secretary Robert F. Kennedy Jr. has been identified as a vaccine skeptic, overseeing a rollback in vaccine guidance for several infectious diseases, including influenza.
The rise in preventable diseases has been alarming; over 2,200 measles cases were documented in the U.S. in 2025, the highest rate in nearly three decades, with more than 730 cases reported this year.
On Wall Street, Moderna has faced significant challenges since achieving notoriety for its COVID-19 vaccine. Recently, the company reported a $200 million loss for the most recent quarter, with profits declining by $13 million from the previous year. Analysts predict that the FDA’s decision complicates Moderna’s plans to rely on seasonal vaccine sales to achieve its cash break-even target by 2028. Following the FDA’s announcement, Moderna’s stock, which has dropped 29% this year and is down over 90% from its 2021 peak, fell initially but showed signs of recovery, remaining down 4.7% in midday trading on Wednesday.
