NCT06560151

Assess Safety and Immunogenicity of A/H5 Inactivated Monovalent Influenza Vaccines at Different Antigen Dose Levels Adjuvanted With AS03 or MF59

Randomized, Double-Blind, Phase 2 Study to Assess Safety and Immunogenicity of A/H5 Inactivated Monovalent Influenza Vaccines at Different Antigen Dose Levels Adjuvanted With AS03® or MF59®

• Status: Completed
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 1,380 (actual)
• Sponsor: Biomedical Advanced Research and Development Authority · Federal
• Sex: All
• Age: 18 Years
• Healthy volunteers: Accepted

Summary

This BARDA-sponsored, randomized, double-blind, phase 2 study is designed to assess safety and immunogenicity of A/H5 inactivated monovalent influenza vaccines at different antigen dose levels adjuvanted with AS03 or MF59.

Detailed description

This is a randomized, double-blind, phase 2 study to assess safety and immunogenicity of egg-based H5N8 and H5N1 influenza vaccines at different antigen dose levels (3.75, 7.5, and 15 μg) adjuvanted with AS03A full dose, AS03A half dose (H5N8 only), or MF59. AS03A is the adjuvant AS03®. Healthy adult male and female (non-pregnant) participants, aged 18 years and older, will be screened for baseline health status to ensure trial eligibility. Participants meeting all the inclusion and none of the exclusion criteria will be randomized to receive vaccine doses according to treatment groups defined by antigen (H5N1 or H5N8), antigen dose level (3.75, 7.5, and 15 μg), and adjuvant (AS03A full dose, AS03A half dose, or MF59). Two doses of adjuvanted vaccine separated by 21 days will be administered to approximately 1380 participants, including 780 participants 18 through 64 years old who will be randomized equally to 1 of 13 treatment groups (A, B, C, D, E, F, G, H, I, J, K, M, and N), and 600 participants ≥65 years old who will be randomized equally to 1 of 10 treatment groups (B, C, E, F, H, I, K, L, N, and O). Safety assessments will be based on solicited Adverse Events (AEs) (local and systemic reactogenicity symptoms) with onset within 8 days following each vaccination, inclusive of the vaccination day (Day 1 through Day 8 and Day 22 through Day 29); unsolicited Treatment Emergent Adverse Events (TEAEs) with onset within 22 days following each vaccination, inclusive of the vaccination day (Day 1 through Day 22 and Day 22 through Day 43); and treatment-emergent Serious Adverse Events (SAEs), Potential Immune-Mediated Diseases (pIMDs), and Medically Attended Adverse Events (MAAEs) occurring during study participation (through Day 203). Immunogenicity assessments will include titer, seroprotection rate, and seroconversion rate based on serum Hemagglutination Inhibition (HAI) antibodies, and titer and seroconversion rate based on serum microneutralization (MN) antibodies. Study vaccines will be prepared and administered by unblinded personnel. All other trial assessments will be performed only by blinded personnel.

Conditions

• Influenza

Interventions

Type	Name	Description
BIOLOGICAL	3.75 µg H5N8 antigen plus full dose AS03A	Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N8 vaccine.
BIOLOGICAL	7.5 µg H5N8 antigen plus full dose AS03A	Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N8 vaccine.
BIOLOGICAL	15 µg H5N8 antigen plus full dose AS03A	Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N8 vaccine.
BIOLOGICAL	3.75 µg H5N8 antigen plus half dose AS03A	Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N8 vaccine.
BIOLOGICAL	7.5 µg H5N8 antigen plus half dose AS03A	Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N8 vaccine.
BIOLOGICAL	15 µg H5N8 antigen plus half dose AS03A	Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N8 vaccine.
BIOLOGICAL	3.75 µg H5N8 antigen plus MF59	Two intramuscular doses (21 days apart) of MF59 adjuvanted H5N8 vaccine.
BIOLOGICAL	7.5 µg H5N8 antigen plus MF59	Two intramuscular doses (21 days apart) of MF59 adjuvanted H5N8 vaccine.
BIOLOGICAL	15 µg H5N8 antigen plus MF59	Two intramuscular doses (21 days apart) of MF59 adjuvanted H5N8 vaccine.
BIOLOGICAL	3.75 µg H5N1 antigen plus full dose AS03A	Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N1 vaccine.
BIOLOGICAL	7.5 µg H5N1 antigen plus full dose AS03A	Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N1 vaccine.
BIOLOGICAL	15 µg H5N1 antigen plus full dose AS03A	Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N1 vaccine.
BIOLOGICAL	3.75 µg H5N1 antigen plus MF59	Two intramuscular doses (21 days apart) of MF59 adjuvanted H5N1 vaccine.
BIOLOGICAL	7.5 µg H5N1 antigen plus MF59	Two intramuscular doses (21 days apart) of MF59 adjuvanted H5N1 vaccine.
BIOLOGICAL	15 µg H5N1 antigen plus MF59	Two intramuscular doses (21 days apart) of MF59 adjuvanted H5N1 vaccine.

Timeline

• Start date: 2024-08-21
• Primary completion: 2025-01-02
• Completion: 2025-06-11
• First posted: 2024-08-19
• Last updated: 2026-01-09

Locations

20 sites across 1 country: United States

Regulatory

• FDA-regulated drug study