News|Articles|May 2, 2025

FDA Asks for More Data for Moderna’s Influenza COVID-19 Combination Vaccine

The company had requested approval for its mRNA-1083 combination vaccine last year. With this setback, the company is now looking at 2026 for approval.

The FDA has requested that Moderna provide more data for its late-stage mRNA-1083 combination influenza/COVID-19 vaccine. Specifically, the federal agency requested more phase 3 influenza efficacy data.1 The company had requested a full approval of the vaccine based upon its data from the phase 3 trials looking at an older adult population.1

Based on FDA feedback, Moderna expects an extended review timeline and is now targeting approval in 2026.1

“With several phase 3 readouts approaching and continued momentum toward 10 product approvals, we remain confident in Moderna's long-term outlook," Moderna CEO Stéphane Bancel, said in a statement. 1

Phase 3 Data

The phase 3 trial is a randomized, observer-blind, active control study evaluating the safety, reactogenicity, and immunogenicity of mRNA-1083 in two independent age group cohorts of approximately 4000 adults each. One cohort, consisting of adults 65 years and older, compared mRNA-1083 to co-administered Fluzone HD, an enhanced influenza vaccine, and Spikevax, Moderna's currently licensed COVID-19 vaccine.2

The other cohort of adults 50 to 64 years of age compared mRNA-1083 to co-administered, Fluarix, a standard dose influenza vaccine, and Spikevax. The immune responses from a single dose of mRNA-1083 were found to be non-inferior versus the co-administered, routinely recommended, licensed comparators. 2

What You Need to Know

The FDA has asked Moderna to provide additional Phase 3 influenza efficacy data before considering approval of its mRNA-1083 combination vaccine.

This request has pushed the anticipated approval timeline to 2026.

The Phase 3 trial results demonstrated that mRNA-1083 produced non-inferior—and in some cases, statistically significantly stronger—immune responses compared to currently licensed flu and COVID-19 vaccines, including Fluzone HD, Fluarix, and Spikevax.

Learn more: Are Combination Respiratory Virus Vaccines the Way of the Future?

In both age cohorts, the Moderna vaccine also elicited statistically significantly higher immune responses against 3 influenza virus strains (H1N1, H3N2, and B/Victoria) and against SARS-CoV-2. In the 65 years and older cohort, overall Geometric Mean Ratios (GMRs) of the mRNA-1083 group compared to the Fluzone HD group for the influenza strains were 1.155 (95% CI: 1.094, 1.220) for A/H1N1, 1.063 (95% CI: 1.007, 1.122) for A/H3N2 and 1.118 (95% CI: 1.070, 1.167) for B/Victoria. The GMR of mRNA-1083 compared to Spikevax for the SARS-CoV-2 variant Omicron XBB.1.5 was 1.641 (95% CI: 1.526, 1.765). 2

In the 50 to 64 years of age cohort the GMRs of the mRNA-1083 group compared to the Fluarix group for the influenza virus strains were 1.414 (95% CI: 1.333, 1.500) for A/H1N1, 1.380 (95% CI: 1.310, 1.454) for A/H3N2, and 1.216 (95% CI: 1.163, 1.270) for B/Victoria. The GMR of mRNA-1083 compared to Spikevax for the SARS-CoV-2 variant Omicron XBB15 was 1.308 (95% CI: 1.219, 1.404). 2

Based on its actions, the current administration is taking a different approach to vaccine approvals from its previous administration as well as the Biden administration. Thus far, there have been delayed and canceled vaccine meetings as well as the FDA’s decision last week to ask Novavax to complete an additional clinical trial for its COVID-19 vaccine, NVX-CoV2601, which sought a full approval for it after it was granted an emergency use authorization in 2022.3 That news came just days after the company received communication from the FDA asking for a postmarketing commitment (PMC) to generate additional clinical data.4

References
1.Moderna Reports First Quarter 2025 Financial Results and Provides Business Updates.Moderna May 1, 2025. Accessed May 2, 2025.
2.Moderna Announces Positive Phase 3 Data for Combination Vaccine Against Influenza and COVID-19. Moderna press release. June 10, 2024. Accessed May 2, 2025.
https://investors.modernatx.com/news/news-details/2024/Moderna-Announces-Positive-Phase-3-Data-for-Combination-Vaccine-Against-Influenza-and-COVID-19-/default.aspx
3.US FDA asks Novavax to complete new clinical trial for delayed COVID-19 shot, WSJ reports. News release. Reuters. April 25, 2025. Accessed May 2, 2025. https://www.reuters.com/business/healthcare-pharmaceuticals/fda-asks-novavax-complete-new-clinical-trial-delayed-covid-19-shot-wsj-reports-2025-04-25/
4. Latest update on U.S. FDA BLA for Novavax's COVID-19 Vaccine. News release. Novavax. April 23, 2025. Accessed May 2, 2025. https://ir.novavax.com/press-releases/Latest-update-on-U-S-FDA-BLA-for-Novavaxs-COVID-19-Vaccine


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