HHS Cancels Moderna’s Award for Developing Avian Influenza Vaccine

This week, Moderna announced the Department of Health and Human Services (HHS) terminated the company's award for late-stage development of an avian influenza (H5) vaccine. In the award termination statement, Moderna also announced positive interim data from its phase 1/2 clinical study evaluating the safety and immunogenicity of its investigational vaccine, mRNA-1018.¹

Despite this news, Moderna plans to explore alternatives for late-stage development and manufacturing of the H5 program.

"While the termination of funding from HHS adds uncertainty, we are pleased by the robust immune response and safety profile observed in this interim analysis of the phase 1/2 study of our H5 avian flu vaccine and we will explore alternative paths forward for the program," Moderna CEO Stéphane Bancel, said in a statement. ¹ 

Last year, HHS, through the Biomedical Advanced Research and Development Authority (BARDA), offered Moderna an approximately $176 million award for development of an mRNA-based pandemic H5 (avian) influenza vaccine.²

The award was made through BARDA’s new Rapid Response Partnership Vehicle (RRPV) Consortium, managed by Advanced Technology International (ATI). The RRPV is a 10-year, multi-purpose acquisition vehicle and consortium partnership designed to support advanced research and development of medical countermeasures, such as vaccines, therapeutics, and diagnostics. The consortium creates flexible, strategic partnerships with industry that foster innovation and promote collaboration. ²

Phase 1/2 Data

The study included approximately 300 healthy adults aged 18 years and older. The interim results focused on the vaccine candidate targeting the H5 avian influenza virus subtype. The study evaluated a 2-dose regimen of mRNA-1018, which demonstrated a rapid, potent and durable immune response.¹

At baseline, pre-existing immunity was minimal, with only 2.1% of participants showing hemagglutination inhibition (HAI) antibody titers ≥1:40, an HAI titer considered to correlate with protection. At Day 43, three weeks after the second vaccination, 97.8% of participants achieved titers ≥1:40 with a 44.5-fold increase of titers from baseline. The investigational vaccine was generally well-tolerated, with no dose-limiting tolerability concerns observed. Most solicited adverse reactions were Grade 1 or 2 and did not increase significantly with number of doses or between first and second doses. ¹

Further data is expected to be submitted for presentation at an upcoming scientific meeting. ¹

Avian Cases in US

As of May 23, the CDC has reported 70 confirmed and probable human cases of avian influenza in the US since the outbreak began in 2024. To date there has been 1 death.³ The majority of these cases have been linked to exposure through commercial agricultural settings, with 41 individuals exposed through infected dairy herds and 24 associated with poultry farms and culling operations. Two additional cases were connected to other animal exposures, including backyard flocks and wild birds, and three remain of unknown origin.⁴

References
1. Moderna Announces Update on Investigational Pandemic Influenza Program. Moderna press release. May 28, 2025. Accessed May 30, 2025.
2. Moderna Receives Project Award through BARDA's Rapid Response Partnership Vehicle Consortium to Accelerate Development of mRNA-based Pandemic Influenza VaccineModerna press release. July 2, 2024. Accessed July 5, 2024.
https://www.accesswire.com/884010/moderna-receives-project-award-through-bardas-rapid-response-partnership-vehicle-consortium-to-accelerate-development-of-mrna-based-pandemic-influenza-vaccine
3. Avian Influenza (Bird Flu). H5 Bird Flu: Current Situation. CDC. Updated April 23, 2025. Accessed May 30, 2025. https://www.cdc.gov/flu/avianflu/index.htm
4. Abene S. Updated H5N1 Report: 70 Human Cases in the US as of April 2025. Contagion. April 15, 2025. Accessed May 30, 2025.
https://www.contagionlive.com/view/updated-h5n1-report-70-human-cases-in-the-us-as-of-april-2025