Moderna announces update on Investigational Pandemic Influenza Program

Moderna  Inc announced positive interim data from a Phase I/II clinical study (NCT05972174) evaluating the safety and immunogenicity of its investigational pandemic flu vaccine, mRNA-1018, in approximately 300 healthy adults aged 18 years and older. The interim results focus on a vaccine candidate targeting the H5 avian influenza virus subtype. The Phase I/II study evaluated a two-dose regimen of Moderna's investigational avian influenza vaccine. mRNA-1018 demonstrated a rapid, potent and durable immune response. 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. Further data is expected to be submitted for presentation at an upcoming scientific meeting.

The Company had previously expected to advance the program to late-stage development with the U.S. Department of Health and Human Services (HHS); however, Moderna received notice that HHS will terminate the award for the late-stage development and right to purchase pre-pandemic influenza vaccines. Moderna will explore alternatives for late-stage development and manufacturing of the H5 program consistent with the Company's strategic commitment to pandemic preparedness.

"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," said Stéphane Bancel, Chief Executive Officer of Moderna. "These clinical data in pandemic influenza underscore the critical role mRNA technology has played as a countermeasure to emerging health threats."