FDA refusing to review Moderna mRNA flu shot application

Moderna said on Tuesday that the Food and Drug Administration (FDA) has refused to review its application for an mRNA flu vaccine, with the company claiming this decision is inconsistent with previous communications from the agency.

In a press release Tuesday, Moderna said the FDA’s Center for Biologics Evaluation and Research (CBER) told the company it would not be initiating a review of its investigational mRNA vaccine. The company has requested a Type A meeting, a high-priority discussion with the FDA, to “understand” a path forward.

CBER Director Vinayak Prasad said the reason for the refusal was because Moderna chose a standard-dose seasonal flu vaccine that has already been licensed as a comparison, according to the company. Moderna argued relevant regulations and guidance don’t reflect this reasoning.

“The letter did not identify any specific safety or efficacy concerns regarding mRNA-1010,” Moderna said.

“This decision by CBER, which did not identify any safety or efficacy concerns with our product, does not further our shared goal of enhancing America’s leadership in developing innovative medicines,” Moderna CEO Stéphane Bancel said in a statement.

“It should not be controversial to conduct a comprehensive review of a flu vaccine submission that uses an FDA-approved vaccine as a comparator in a study that was discussed and agreed on with CBER prior to starting,” he added. “We look forward to engaging with CBER to understand the path forward as quickly as possible so that America’s seniors, and those with underlying conditions, continue to have access to American-made innovations.”

In a press briefing Wednesday, the FDA shared a statement from agency Commissioner Marty Makary.

“The FDA rejected Moderna’s application for filing because the company refused to follow very clear FDA guidance from 2024 to test its product in a clinical trial against a CDC recommended flu vaccine to compare safety and efficacy,” the statement said. “Moderna exposed participants, age 65 and over, to increased risk of severe illness by giving them a substandard of care against the recommendation of FDA career scientists.”

Last year, the Department of Health and Human Services (HHS) canceled millions in funding grants for mRNA vaccines, with HHS Secretary Robert F. Kennedy Jr. claiming at the time this decision was due to data showing these types of vaccines are ineffective.

A senior FDA official said in the Wednesday briefing that Kennedy had nothing to do with the FDA’s decision and was likely not even aware of the agency’s refusal to file until news was published.

When asked if Moderna could resubmit the same data, the same official said it was “entirely feasible that if they come back, maybe even show some humility.”

In response to these claims by the FDA, Moderna said in a statement to The Hill, “The FDA reviewed and cleared the trial design as adequate before the study began 18 months ago. The industry depends on clear, transparent rules that are applied consistently in order to make the long-term investments that benefit Americans.”

Stat reported that CBER Director Prasad had overruled FDA staff reviews when deciding to reject Moderna’s application. The FDA official declined to comment on the “gossip” and said there was “healthy scientific debate on the refuse to file.”

The FDA has already approved two seasonal mRNA vaccines for COVID-19.

Sen. Patty Murray (D-Wash.), a member of the Senate Committee on Health, Education, Labor, and Pensions, blasted the decision on social media.

“RFK Jr. is now blocking an updated flu vaccine for no reason grounded in science. American vaccine policy has been hijacked by a conspiracy theorist—yet most Republicans are happy to just sit on their hands,” Murray wrote on the social media platform X. “They are allowing FDA policy to be dictated by DELUSION.”