FDA advisers back Moderna mRNA flu vaccine in unanimous vote

Independent advisers to the Food and Drug Administration voted 9-0 Friday to recommend approval of Moderna’s seasonal mRNA flu vaccine. The vote puts the shot, called mRNA-1010 and branded mFlusiva, closer to a final agency decision after an earlier FDA refusal to review it was overturned.

The Vaccines and Related Biological Products Advisory Committee spent the day reviewing company data and presentations, including an FDA scientific review that supported the vaccine, according to Ars Technica. The FDA is not bound by the panel’s vote, but advisory support often weighs in the agency’s final review.

Trial data discussed at the meeting showed mRNA-1010 performed better than a standard flu shot in a large Phase 3 study of more than 40,000 adults ages 50 and older. The vaccine was about 27% more effective against seasonal flu than the comparator shot, according to the data reviewed by the committee.

A separate Phase 3 study with nearly 3,000 adults ages 65 and older found that Moderna’s vaccine generated stronger immune responses than a high-dose flu vaccine recommended for that age group. The safety findings presented to the panel were generally favorable, according to the review.

Advisers cite trial results and mRNA platform

Flor Munoz-Rivas, a VRBPAC voting member and pediatric infectious disease specialist at Baylor College of Medicine, said after the vote that the studies were well run and produced clear results showing added efficacy. She also pointed to the mRNA platform’s ability to support faster seasonal vaccine development and preparation for future flu strains.

Hayley Gans, a VRBPAC voting member and pediatric infectious disease specialist at Stanford University, also backed the platform. She said the safety signals presented did not suggest people were being put at risk and that the vaccine could help move flu vaccine development toward newer technology.

Moderna said it was pleased with the panel’s decision. Chief Executive Stéphane Bancel said in a company statement that the clinical evidence supports mRNA-1010 and that the company will keep working with the FDA as the agency finishes its review.

Earlier FDA refusal was reversed

The vote followed months of internal FDA conflict over whether the agency would review the application. Ars Technica reported that Vinay Prasad, then overseeing vaccines at the FDA as a Trump appointee, rejected Moderna’s filing in February and argued that the large trial was not adequate because it did not compare efficacy against a high-dose flu vaccine in adults 65 and older.

Moderna instead used the smaller older-adult trial to compare immune responses against a high-dose vaccine, a plan Ars Technica reported the FDA had previously accepted. The FDA reversed the refusal a week later and agreed to review the vaccine.

Prasad left the FDA at the end of April after several disputed decisions, according to Ars Technica. One of those decisions involved UniQure’s Huntington’s disease gene therapy; that rejection was reversed Wednesday.

FDA and CDC steps remain

The FDA has set an Aug. 5 deadline for its decision on mRNA-1010. Moderna has previously said it wants to release the vaccine later this year if it wins approval.

A CDC recommendation would still be needed for broad use and coverage. Newly approved vaccines are typically reviewed by the CDC’s Advisory Committee on Immunization Practices, whose recommendations can trigger no-cost coverage requirements for most commercial insurers and federal programs.

That step is uncertain because a federal judge temporarily blocked most of the advisers installed on ACIP by Health Secretary Robert F. Kennedy Jr., ruling they were improperly appointed, according to Ars Technica. The Department of Health and Human Services is appealing the injunction on an expedited schedule that is expected to run at least into July.

This story draws on original reporting from Ars Technica.