CompletedNCT06560151Updated Jul 23, 2026Results posted

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

A Phase 2 interventional study of 3.75 µg H5N8 antigen plus full dose AS03A and 7.5 µg H5N8 antigen plus full dose AS03A in Influenza, sponsored by Biomedical Advanced Research and Development Authority. Completed at 20 sites in United States. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-07-23.

Sponsored by Biomedical Advanced Research and Development Authority · Phase 2, Interventional, and Other

Phase: Phase 2
Study type: Interventional
Enrollment: 1,380
Allocation: Randomized
Ages: 18 Years and older
Sex: All

Study 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.

Read the 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 studied

Influenza

Browse trials for

Influenza, Human 2,209

Keywords

A/H5
H5
Inactivated
Monovalent
Influenza
Vaccines
AS03
MF59

Who can participate

Ages eligible: 18 Years and older
Sexes eligible: All
Accepts healthy volunteers: Yes

Inclusion criteria

Male or non-pregnant female, 18 years of age or older at the time of screening and informed consent.
Willing and able to provide written informed consent prior to initiation of study procedures.
Agrees to have specimens collected during this trial specifically for the purpose of future research stored for future research use.
In relatively stable health, as determined by medical history and physical examination.
a. Any chronic medical diagnoses or conditions should be stable and well managed, with no significant changes expected during the study period, and in the opinion of the site investigator, will not impact the ability to assess safety and/or immunogenicity per the study design.
If a female of childbearing potential who is sexually active, agrees to use an adequate method of birth control from Screening through 4 weeks following the last study vaccination and has used an adequate birth control method for at least 2 months prior to Screening.
a. Female of childbearing potential is defined as post onset menarche and pre-menopausal person capable of becoming pregnant. This does not include females who meet any of the following conditions:
i. menopausal >2 years
ii. tubal ligation >1 year
iii. bilateral salpingo-oophorectomy
iv. hysterectomy.
b. Adequate contraception is defined as a contraceptive method with a failure rate of less than 1% per year when used consistently and correctly and when applicable, in accordance with the product label, for example: oral contraceptives, either combined or progestogen alone; injectable progestogen; implants of etonogestrel or levonorgestrel; estrogenic vaginal ring; percutaneous contraceptive patches; intrauterine device or intrauterine system; the female participant has exclusively female sexual partners; male partner is sterile or otherwise unable to produce sperm (information on the person's sterility can come from the site personnel's review of the participant's medical records or interview with the participant regarding her medical history); male condom combined with a vaginal spermicide (foam, gel, film, cream, or suppository); or male condom combined with a female diaphragm, either with or without a vaginal spermicide (foam, gel, film, cream, or suppository).
Available for all study visits, willing to participate in all study procedures, and not planning to relocate from the area for the duration of the study.

Exclusion criteria

Exclusion Criteria:

Has an acute illness, as determined by the site investigator, within 72 hours prior to vaccination.
a. An acute illness that is nearly resolved, with only minor residual symptoms remaining, is allowable if, in the opinion of the site investigator, the residual symptoms will not interfere with the ability of study staff to assess safety parameters as required by the protocol.
Has a history of severe reaction to any influenza vaccine.
Has a known allergy to squalene-based adjuvants.
Female of childbearing potential who has a positive urine pregnancy test or who is currently breastfeeding.
Has a body mass index >35 kg/m2 .
Has known human immunodeficiency virus, hepatitis B, or hepatitis C infection (based on medical history).
Has a history of any pIMDs (list provided in Protocol Appendix 3), neuralgia, paresthesia, neuritis, convulsions, or encephalomyelitis within 90 days prior to Screening, or a family history of Guillain-Barré syndrome.
Has narcolepsy or a first degree relative with narcolepsy.
Has a history of alcohol or drug abuse within 5 years prior to Screening.
Has any diagnosis, current or past, of schizophrenia, bipolar disease, or any other psychiatric diagnosis that may, in the opinion of the site investigator, interfere with participant compliance or safety evaluations.
Is immunosuppressed due to an underlying disease or medication, use of anticancer chemotherapy (cytotoxic), or radiation therapy.
With the exception of basal or squamous cell skin cancer, has known active neoplastic disease, including hematologic malignancy.
Has long-term use (≥14 consecutive days) of glucocorticoids including oral or parenteral prednisone or prednisone equivalent (>20 mg total dose per day) or high-dose inhaled steroids (>800 µg/day of beclomethasone dipropionate or equivalent) within 1 month prior to screening in this study. However, participants on low-dose inhaled steroids (≤800 µg/day of beclomethasone dipropionate or equivalent) or topical steroids are not excluded.
Has received immunoglobulin or other blood product (with the exception of Rho[D] immune globulin) within the 90 days prior to screening in this study.
Has received any (licensed or under Emergency Use Authorization [EUA]) live vaccines within 4 weeks or inactivated, messenger RNA (mRNA), or recombinant protein vaccines within 2 weeks prior to screening, or plans to receive such vaccines (including seasonal influenza and COVID-19 vaccines) from screening through 22 days following the second dose of the study vaccine, inclusive of the vaccination day (Screening Visit through Day 43).
Is participating or plans to participate in another interventional clinical trial (either active or follow-up phase) during the study period.
Has participated in an A(H5) influenza vaccine study in the past or has a history of A(H5) influenza infection prior to vaccination in this study. This includes, but is not limited to, influenza sub-types A(H5N1), A(H5N8), and A(H5N6).
Has any laboratory test result or clinical findings (including vital signs) that singly or in combination are likely to unfavorably alter the risks of participant participation or to confound study safety or immunogenicity results, in the opinion of the site investigator. Additionally, the following are exclusionary:
1. Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) >2 times the upper limit of normal (ULN), or
2. Bilirubin >1.5 times the ULN unless isolated Gilbert's syndrome.
Has any disease or medical condition that, in the opinion of the site investigator, might confound interpretation of safety or immunogenicity.

Study design

Phase: Phase 2
Primary purpose: Other
Allocation: Randomized
Intervention model: Parallel assignment
Masking: Quadruple (Participant, Care provider, Investigator, Outcomes assessor)
Enrollment: 1,380 participants (actual)

Study arms

Experimental
Treatment Group A
This treatment group of 60 participants (ages 18-64) in Treatment Group A will receive 3.75 µg of Egg-A/Astrakhan/3212/2020 (H5N8) antigen adjuvanted with a full dose of AS03A.
Biological: 3.75 µg H5N8 antigen plus full dose AS03A
Experimental
Treatment Group B
This treatment group of 120 participants (60 participants ages 18-64 and 60 participants ages ≥65) in Treatment Group B will receive 7.5 µg of Egg-A/Astrakhan/3212/2020 (H5N8) adjuvanted with a full dose of AS03A.
Biological: 7.5 µg H5N8 antigen plus full dose AS03A
Experimental
Treatment Group C
This treatment group of 120 participants (60 participants ages 18-64 and 60 participants age ≥65) will receive 15 µg of Egg-A/Astrakhan/3212/2020 (H5N8) adjuvanted with a full dose of AS03A.
Biological: 15 µg H5N8 antigen plus full dose AS03A
Experimental
Treatment Group D
This treatment group of 60 participants (ages 18-64) will receive 3.75 µg of Egg-A/Astrakhan/3212/2020 (H5N8) adjuvanted with a half dose of AS03A.
Biological: 3.75 µg H5N8 antigen plus half dose AS03A
Experimental
Treatment Group E
This treatment group of 120 participants (60 participants ages 18-64 and 60 participants age ≥65) will receive 7.5 µg of Egg-A/Astrakhan/3212/2020 (H5N8) adjuvanted with a half dose of AS03A.
Biological: 7.5 µg H5N8 antigen plus half dose AS03A
Experimental
Treatment Group F
This treatment group of 120 participants (60 participants ages 18-64 and 60 participants age ≥65 will receive 15 µg of Egg-A/Astrakhan/3212/2020 (H5N8) adjuvanted with a half dose of AS03A.
Biological: 15 µg H5N8 antigen plus half dose AS03A
Experimental
Treatment Group G
This treatment group of 60 participants (ages 18-64) will receive 3.75 µg of Egg-A/Astrakhan/3212/2020 (H5N8) adjuvanted with MF59.
Biological: 3.75 µg H5N8 antigen plus MF59
Experimental
Treatment Group H
This treatment group of 120 participants (60 participants ages 18-64 and 60 participants age ≥65) will receive 7.5 µg of Egg-A/Astrakhan/3212/2020 (H5N8) adjuvanted with MF59.
Biological: 7.5 µg H5N8 antigen plus MF59
Experimental
Treatment Group I
This treatment group of 120 participants (60 participants ages 18-64 and 60 participants age ≥65) will receive 15 µg of Egg-A/Astrakhan/3212/2020 (H5N8) adjuvanted with MF59.
Biological: 15 µg H5N8 antigen plus MF59
Experimental
Treatment Group J
This treatment group of 60 participants (ages 18-64) will receive 3.75 µg of Egg-A/bar-headed goose/Qinghai Lake/1A/2005 (H5N1) adjuvanted with a full dose of AS03A.
Biological: 3.75 µg H5N1 antigen plus full dose AS03A
Experimental
Treatment Group K
This treatment group of 120 participants (60 participants ages 18-64 and 60 participants age ≥65) will receive 7.5 µg of Egg-A/bar-headed goose/Qinghai Lake/1A/2005 (H5N1) adjuvanted with a full dose of AS03A.
Biological: 7.5 µg H5N1 antigen plus full dose AS03A
Experimental
Treatment Group L
This treatment group of 60 participants (ages ≥65) will receive 15 µg of Egg-A/bar-headed goose/Qinghai Lake/1A/2005 (H5N1) adjuvanted with a full dose of AS03A.
Biological: 15 µg H5N1 antigen plus full dose AS03A
Experimental
Treatment Group M
This treatment group of 60 participants (ages 18-64) will receive 3.75 µg of Egg-A/bar-headed goose/Qinghai Lake/1A/2005 (H5N1) adjuvanted with MF59.
Biological: 3.75 µg H5N1 antigen plus MF59
Experimental
Treatment Group N
This treatment group of 120 participants (60 participants ages 18-64 and 60 participants age ≥65) will receive 7.5 µg of Egg-A/bar-headed goose/Qinghai Lake/1A/2005 (H5N1) adjuvanted with MF59.
Biological: 7.5 µg H5N1 antigen plus MF59
Experimental
Treatment Group O
This treatment group of 60 participants (age ≥65) will receive 15 µg of Egg-A/bar-headed goose/Qinghai Lake/1A/2005 (H5N1) adjuvanted with MF59.
Biological: 15 µg H5N1 antigen plus MF59

Interventions

Biological3.75 µg H5N8 antigen plus full dose AS03A
Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N8 vaccine.
Biological7.5 µg H5N8 antigen plus full dose AS03A
Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N8 vaccine.
Biological15 µg H5N8 antigen plus full dose AS03A
Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N8 vaccine.
Biological3.75 µg H5N8 antigen plus half dose AS03A
Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N8 vaccine.
Biological7.5 µg H5N8 antigen plus half dose AS03A
Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N8 vaccine.
Biological15 µg H5N8 antigen plus half dose AS03A
Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N8 vaccine.
Biological3.75 µg H5N8 antigen plus MF59
Two intramuscular doses (21 days apart) of MF59 adjuvanted H5N8 vaccine.
Biological7.5 µg H5N8 antigen plus MF59
Two intramuscular doses (21 days apart) of MF59 adjuvanted H5N8 vaccine.
Biological15 µg H5N8 antigen plus MF59
Two intramuscular doses (21 days apart) of MF59 adjuvanted H5N8 vaccine.
Biological3.75 µg H5N1 antigen plus full dose AS03A
Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N1 vaccine.
Biological7.5 µg H5N1 antigen plus full dose AS03A
Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N1 vaccine.
Biological15 µg H5N1 antigen plus full dose AS03A
Two intramuscular doses (21 days apart) of AS03A adjuvanted H5N1 vaccine.
Biological3.75 µg H5N1 antigen plus MF59
Two intramuscular doses (21 days apart) of MF59 adjuvanted H5N1 vaccine.
Biological7.5 µg H5N1 antigen plus MF59
Two intramuscular doses (21 days apart) of MF59 adjuvanted H5N1 vaccine.
Biological15 µg H5N1 antigen plus MF59
Two intramuscular doses (21 days apart) of MF59 adjuvanted H5N1 vaccine.

What researchers measure

Primary outcomes

The Percentage of Participants Who Experience Any Solicited Local Reactogenicity Symptom Occurring Within 8 Days of Each Vaccination, Inclusive of the Vaccination Day.
The percentage of participants who experienced at least one solicited local reactogenicity adverse event at the injection site during at least one of the time frames specified. Possible reactions included erythema/redness, induration (underlying hardening of tissue associated with inflammation)/swelling (localized tissue distention), and pain.
Time frame: Day 1 through Day 8 and Day 22 through Day 29
The Percentage of Participants Who Experience Any Solicited Systemic Reactogenicity Symptom Occurring Within 8 Days of Each Vaccination, Inclusive of the Vaccination Day.
The percentage of participants who experienced at least one solicited systemic reactogenicity adverse event during at least one of the time frames specified. Possible reactions included fever, myalgia, arthralgia, fatigue, headache, nausea, vomiting, diarrhea, and chills.
Time frame: Day 1 through Day 8 and Day 22 through Day 29
The Percentage of Participants Achieving Seroprotection at Day 43 Based on Serum HAI Antibody Titers (≥1:40) to A/Astrakhan (H5N8).
The percentage of participants achieving seroprotection, defined as serum HAI antibody titer ≥ 1:40 against the H5N8 antigen. A titer of 1:40 or greater is considered to be a sufficient amount of antibody to avoid infection in half of exposed individuals.
Time frame: Day 43

Secondary outcomes

The Percentage of Participants Who Experience Any Unsolicited Treatment-emergent Adverse Event (TEAE) Within 22 Days of Each Vaccination, Inclusive of the Vaccination Day.
The percentage of participants who experienced at least one unsolicited TEAE during at least one of the time frames specified. Unsolicited TEAEs were defined as any adverse event other than those included in the lists for solicited local and systemic reactions.
Time frame: Day 1 through Day 22 and Day 22 through Day 43
The Percentage of Participants Who Experience Any Treatment-emergent Serious Adverse Event (SAE).
The percentage of participants who experienced at least one treatment-emergent SAE during the time frame specified.
Time frame: Day 1 through Day 203
The Percentage of Participants Who Experience Any Treatment-emergent Medically Attended Adverse Events (MAAE).
The percentage of participants who experienced at least one treatment-emergent MAAE during the time frame specified. MAAEs were defined as adverse events with medically attended visits including hospital, emergency room, urgent care clinic, or other visits to or from medical personnel for any reason.
Time frame: Day 1 through Day 203
The Percentage of Participants Who Experience Any Treatment-emergent Potentially Immune-mediated Disease (pIMD).
The percentage of participants who experienced at least one treatment-emergent pIMD during the time frame specified. A comprehensive list of adverse events to be reported as pIMDs is available in Appendix 3 of the Protocol.
Time frame: Day 1 through Day 203
The Percentage of Participants Achieving Seroprotection at Day 43 Based on Serum HAI Antibody Titers (≥1:40) to A/Bar-headed Goose (H5N1).
The percentage of participants achieving seroprotection, defined as serum HAI antibody titer ≥ 1:40 against the H5N1 antigen. A titer of 1:40 or greater is considered to be a sufficient amount of antibody to avoid infection in half of exposed individuals.
Time frame: Day 43
Serum HAI Antibody Titers to A/Astrakhan (H5N8) at Screening.
Serum HAI antibody titer levels against the H5N8 antigen. A higher HAI titer means a better immune response against the antigen.
Time frame: Screening (i.e., pre-vaccination)
Serum HAI Antibody Titers to A/Astrakhan (H5N8) at Day 22.
Serum HAI antibody titer levels against the H5N8 antigen. A higher HAI titer means a better immune response against the antigen.
Time frame: Day 22
Serum HAI Antibody Titers to A/Astrakhan (H5N8) at Day 43.
Serum HAI antibody titer levels against the H5N8 antigen. A higher HAI titer means a better immune response against the antigen.
Time frame: Day 43
Serum HAI Antibody Titers to A/Astrakhan (H5N8) at Day 203.
Serum HAI antibody titer levels against the H5N8 antigen. A higher HAI titer means a better immune response against the antigen.
Time frame: Day 203
Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1) at Screening.
Serum HAI antibody titer levels against the H5N1 antigen. A higher HAI titer means a better immune response against the antigen.
Time frame: Screening (i.e., pre-vaccination)
Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1) at Day 22.
Serum HAI antibody titer levels against the H5N1 antigen. A higher HAI titer means a better immune response against the antigen.
Time frame: Day 22
Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1) at Day 43.
Serum HAI antibody titer levels against the H5N1 antigen. A higher HAI titer means a better immune response against the antigen.
Time frame: Day 43
Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1) at Day 203
Serum HAI antibody titer levels against the H5N1 antigen. A higher HAI titer means a better immune response against the antigen.
Time frame: Day 203
The Percentage of Participants Achieving Seroprotection at Day 22 Based on Serum HAI Antibody Titers (≥1:40) to A/Astrakhan (H5N8).
The percentage of participants achieving seroprotection, defined as serum HAI antibody titer ≥ 1:40 against the H5N8 antigen. A titer of 1:40 or greater is considered to be a sufficient amount of antibody to avoid infection in half of exposed individuals.
Time frame: Day 22
The Percentage of Participants Achieving Seroprotection at Day 203 Based on Serum HAI Antibody Titers (≥1:40) to A/Astrakhan (H5N8).
The percentage of participants achieving seroprotection, defined as serum HAI antibody titer ≥ 1:40 against the H5N8 antigen. A titer of 1:40 or greater is considered to be a sufficient amount of antibody to avoid infection in half of exposed individuals.
Time frame: Day 203
The Percentage of Participants Achieving Seroprotection at Day 22 Based on Serum HAI Antibody Titers (≥1:40) to A/Bar-headed Goose (H5N1).
The percentage of participants achieving seroprotection, defined as serum HAI antibody titer ≥ 1:40 against the H5N1 antigen. A titer of 1:40 or greater is considered to be a sufficient amount of antibody to avoid infection in half of exposed individuals.
Time frame: Day 22
The Percentage of Participants Achieving Seroprotection at Day 203 Based on Serum HAI Antibody Titers (≥1:40) to A/Bar-headed Goose (H5N1).
The percentage of participants achieving seroprotection, defined as serum HAI antibody titer ≥ 1:40 against the H5N1 antigen. A titer of 1:40 or greater is considered to be a sufficient amount of antibody to avoid infection in half of exposed individuals.
Time frame: Day 203
The Percentage of Participants Achieving Seroconversion at Day 22 Based on Serum HAI Antibody Titers to A/Astrakhan (H5N8).
The percentage of participants achieving seroconversion, defined as either a pre-vaccination HAI antibody titer \<1:10 and a post-vaccination HAI titer ≥ 1:40, or a pre-vaccination HAI titer ≥1:10 and a minimum 4-fold rise in post-vaccination HAI titer against the H5N8 antigen. Seroconversion represents the minimum intended effect of vaccination.
Time frame: Day 22
The Percentage of Participants Achieving Seroconversion at Day 43 Based on Serum HAI Antibody Titers to A/Astrakhan (H5N8).
The percentage of participants achieving seroconversion, defined as either a pre-vaccination HAI antibody titer \<1:10 and a post-vaccination HAI titer ≥ 1:40, or a pre-vaccination HAI titer ≥1:10 and a minimum 4-fold rise in post-vaccination HAI titer against the H5N8 antigen. Seroconversion represents the minimum intended effect of vaccination.
Time frame: Day 43
The Percentage of Participants Achieving Seroconversion at Day 203 Based on Serum HAI Antibody Titers to A/Astrakhan (H5N8).
The percentage of participants achieving seroconversion, defined as either a pre-vaccination HAI antibody titer \<1:10 and a post-vaccination HAI titer ≥ 1:40, or a pre-vaccination HAI titer ≥1:10 and a minimum 4-fold rise in post-vaccination HAI titer against the H5N8 antigen. Seroconversion represents the minimum intended effect of vaccination.
Time frame: Day 203
The Percentage of Participants Achieving Seroconversion at Day 22 Based on Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1).
The percentage of participants achieving seroconversion, defined as either a pre-vaccination HAI antibody titer \<1:10 and a post-vaccination HAI titer ≥ 1:40, or a pre-vaccination HAI titer ≥1:10 and a minimum 4-fold rise in post-vaccination HAI titer against the H5N1 antigen. Seroconversion represents the minimum intended effect of vaccination.
Time frame: Day 22
The Percentage of Participants Achieving Seroconversion at Day 43 Based on Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1).
The percentage of participants achieving seroconversion, defined as either a pre-vaccination HAI antibody titer \<1:10 and a post-vaccination HAI titer ≥ 1:40, or a pre-vaccination HAI titer ≥1:10 and a minimum 4-fold rise in post-vaccination HAI titer against the H5N1 antigen. Seroconversion represents the minimum intended effect of vaccination.
Time frame: Day 43
The Percentage of Participants Achieving Seroconversion at Day 203 Based on Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1).
The percentage of participants achieving seroconversion, defined as either a pre-vaccination HAI antibody titer \<1:10 and a post-vaccination HAI titer ≥ 1:40, or a pre-vaccination HAI titer ≥1:10 and a minimum 4-fold rise in post-vaccination HAI titer against the H5N1 antigen. Seroconversion represents the minimum intended effect of vaccination.
Time frame: Day 203
Serum MN Antibody Titers to A/Astrakhan (H5N8) at Screening.
Serum MN antibody titer levels against the H5N8 antigen. A higher MN titer means a better immune response against the antigen.
Time frame: Screening (i.e., pre-vaccination)
Serum MN Antibody Titers to A/Astrakhan (H5N8) at Day 22.
Serum MN antibody titer levels against the H5N8 antigen. A higher MN titer means a better immune response against the antigen.
Time frame: Day 22
Serum MN Antibody Titers to A/Astrakhan (H5N8) at Day 43.
Serum MN antibody titer levels against the H5N8 antigen. A higher MN titer means a better immune response against the antigen.
Time frame: Day 43
Serum MN Antibody Titers to A/Astrakhan (H5N8) at Day 203.
Serum MN antibody titer levels against the H5N8 antigen. A higher MN titer means a better immune response against the antigen.
Time frame: Day 203
Serum MN Antibody Titers to A/Bar-headed Goose (H5N1) at Screening.
Serum MN antibody titer levels against the H5N1 antigen. A higher MN titer means a better immune response against the antigen.
Time frame: Screening (i.e., pre-vaccination)
Serum MN Antibody Titers to A/Bar-headed Goose (H5N1) at Day 22.
Serum MN antibody titer levels against the H5N1 antigen. A higher MN titer means a better immune response against the antigen.
Time frame: Day 22
Serum MN Antibody Titers to A/Bar-headed Goose (H5N1) at Day 43.
Serum MN antibody titer levels against the H5N1 antigen. A higher MN titer means a better immune response against the antigen.
Time frame: Day 43
Serum MN Antibody Titers to A/Bar-headed Goose (H5N1) at Day 203.
Serum MN antibody titer levels against the H5N1 antigen. A higher MN titer means a better immune response against the antigen.
Time frame: Day 203
The Percentage of Participants Achieving Seroconversion at Day 22 Based on Serum MN Antibody Titers to A/Astrakhan (H5N8).
The percentage of participants achieving seroconversion, defined as either a pre-vaccination MN antibody titer \<1:10 and a post-vaccination MN titer ≥ 1:40, or a pre-vaccination MN titer ≥1:10 and a minimum 4-fold rise in post-vaccination MN titer against the H5N8 antigen. Seroconversion represents the minimum intended effect of vaccination.
Time frame: Day 22
The Percentage of Participants Achieving Seroconversion at Day 43 Based on Serum MN Antibody Titers to A/Astrakhan (H5N8).
The percentage of participants achieving seroconversion, defined as either a pre-vaccination MN antibody titer \<1:10 and a post-vaccination MN titer ≥ 1:40, or a pre-vaccination MN titer ≥1:10 and a minimum 4-fold rise in post-vaccination MN titer against the H5N8 antigen. Seroconversion represents the minimum intended effect of vaccination.
Time frame: Day 43
The Percentage of Participants Achieving Seroconversion at Day 203 Based on Serum MN Antibody Titers to A/Astrakhan (H5N8).
The percentage of participants achieving seroconversion, defined as either a pre-vaccination MN antibody titer \<1:10 and a post-vaccination MN titer ≥ 1:40, or a pre-vaccination MN titer ≥1:10 and a minimum 4-fold rise in post-vaccination MN titer against the H5N8 antigen. Seroconversion represents the minimum intended effect of vaccination.
Time frame: Day 203
The Percentage of Participants Achieving Seroconversion at Day 22 Based on Serum MN Antibody Titers to A/Bar-headed Goose (H5N1).
The percentage of participants achieving seroconversion, defined as either a pre-vaccination MN antibody titer \<1:10 and a post-vaccination MN titer ≥ 1:40, or a pre-vaccination MN titer ≥1:10 and a minimum 4-fold rise in post-vaccination MN titer against the H5N1 antigen. Seroconversion represents the minimum intended effect of vaccination.
Time frame: Day 22
The Percentage of Participants Achieving Seroconversion at Day 43 Based on Serum MN Antibody Titers to A/Bar-headed Goose (H5N1).
The percentage of participants achieving seroconversion, defined as either a pre-vaccination MN antibody titer \<1:10 and a post-vaccination MN titer ≥ 1:40, or a pre-vaccination MN titer ≥1:10 and a minimum 4-fold rise in post-vaccination MN titer against the H5N1 antigen. Seroconversion represents the minimum intended effect of vaccination.
Time frame: Day 43
The Percentage of Participants Achieving Seroconversion at Day 203 Based on Serum MN Antibody Titers to A/Bar-headed Goose (H5N1).
The percentage of participants achieving seroconversion, defined as either a pre-vaccination MN antibody titer \<1:10 and a post-vaccination MN titer ≥ 1:40, or a pre-vaccination MN titer ≥1:10 and a minimum 4-fold rise in post-vaccination MN titer against the H5N1 antigen. Seroconversion represents the minimum intended effect of vaccination.
Time frame: Day 203

Results

Posted Jul 23, 2026

Participant flow

Twenty clinical sites in the United States screened and enrolled participants into the trial.

Participant flow — Overall Study
Milestone	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
Started	61	121	121	60	119	120	60	120	119	60	118	59	60	121	61
Completed	55	110	108	53	110	110	55	112	109	55	112	58	55	113	58
Not completed	6	11	13	7	9	10	5	8	10	5	6	1	5	8	3
Withdrew: Lost to follow-up	3	7	10	5	6	6	2	5	5	3	3	1	4	7	2
Withdrew: Withdrawal by subject	2	3	3	0	3	4	3	3	5	1	3	0	1	0	1
Withdrew: Non-compliance with study schedule	1	1	0	2	0	0	0	0	0	1	0	0	0	0	0
Withdrew: Subject incarcerated	0	0	0	0	0	0	0	0	0	0	0	0	0	1	0

Outcome measures

PrimaryThe Percentage of Participants Who Experience Any Solicited Local Reactogenicity Symptom Occurring Within 8 Days of Each Vaccination, Inclusive of the Vaccination Day.

The percentage of participants who experienced at least one solicited local reactogenicity adverse event at the injection site during at least one of the time frames specified. Possible reactions included erythema/redness, induration (underlying hardening of tissue associated with inflammation)/swelling (localized tissue distention), and pain.

Time frame:: Day 1 through Day 8 and Day 22 through Day 29
Reported as:: Number · Percentage of Participants

The Percentage of Participants Who Experience Any Solicited Local Reactogenicity Symptom Occurring Within 8 Days of Each Vaccination, Inclusive of the Vaccination Day.
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	62.3 (49.0 to 74.4)	59.0 (45.7 to 71.4)	67.2 (54.0 to 78.7)	43.3 (30.6 to 56.8)	60.0 (46.5 to 72.4)	60.0 (46.5 to 72.4)	48.3 (35.2 to 61.6)	38.3 (26.1 to 51.8)	28.8 (17.8 to 42.1)	61.7 (48.2 to 73.9)	72.4 (59.1 to 83.3)	—	33.3 (21.7 to 46.7)	35.0 (23.1 to 48.4)	—
>65 years	—	38.3 (26.1 to 51.8)	30.0 (18.8 to 43.2)	—	45.8 (32.7 to 59.2)	41.7 (29.1 to 55.1)	—	20.0 (10.8 to 32.3)	23.3 (13.4 to 36.0)	—	46.7 (33.7 to 60.0)	47.5 (34.3 to 60.9)	—	18.0 (9.4 to 30.0)	36.1 (24.2 to 49.4)
Overall	62.3 (49.0 to 74.4)	48.8 (39.6 to 58.0)	48.8 (39.6 to 58.0)	43.3 (30.6 to 56.8)	52.9 (43.6 to 62.2)	50.8 (41.6 to 60.1)	48.3 (35.2 to 61.6)	29.2 (21.2 to 38.2)	26.1 (18.4 to 34.9)	61.7 (48.2 to 73.9)	59.3 (49.9 to 68.3)	47.5 (34.3 to 60.9)	33.3 (21.7 to 46.7)	26.4 (18.8 to 35.2)	36.1 (24.2 to 49.4)

PrimaryThe Percentage of Participants Who Experience Any Solicited Systemic Reactogenicity Symptom Occurring Within 8 Days of Each Vaccination, Inclusive of the Vaccination Day.

The percentage of participants who experienced at least one solicited systemic reactogenicity adverse event during at least one of the time frames specified. Possible reactions included fever, myalgia, arthralgia, fatigue, headache, nausea, vomiting, diarrhea, and chills.

Time frame:: Day 1 through Day 8 and Day 22 through Day 29
Reported as:: Number · Percentage of Participants

The Percentage of Participants Who Experience Any Solicited Systemic Reactogenicity Symptom Occurring Within 8 Days of Each Vaccination, Inclusive of the Vaccination Day.
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	50.8 (37.7 to 63.9)	52.5 (39.3 to 65.4)	55.7 (42.4 to 68.5)	35.0 (23.1 to 48.4)	38.3 (26.1 to 51.8)	48.3 (35.2 to 61.6)	48.3 (35.2 to 61.6)	41.7 (29.1 to 55.1)	18.6 (9.7 to 30.9)	48.3 (35.2 to 61.6)	51.7 (38.2 to 65.0)	—	30.0 (18.8 to 43.2)	38.3 (26.1 to 51.8)	—
>65 years	—	41.7 (29.1 to 55.1)	28.3 (17.5 to 41.4)	—	35.6 (23.6 to 49.1)	38.3 (26.1 to 51.8)	—	23.3 (13.4 to 36.0)	23.3 (13.4 to 36.0)	—	33.3 (21.7 to 46.7)	32.2 (20.6 to 45.6)	—	21.3 (11.9 to 33.7)	18.0 (9.4 to 30.0)
Overall	50.8 (37.7 to 63.9)	47.1 (38.0 to 56.4)	42.1 (33.2 to 51.5)	35.0 (23.1 to 48.4)	37.0 (28.3 to 46.3)	43.3 (34.3 to 52.7)	48.3 (35.2 to 61.6)	32.5 (24.2 to 41.7)	21.0 (14.1 to 29.4)	48.3 (35.2 to 61.6)	42.4 (33.3 to 51.8)	32.2 (20.6 to 45.6)	30.0 (18.8 to 43.2)	29.8 (21.8 to 38.7)	18.0 (9.4 to 30.0)

PrimaryThe Percentage of Participants Achieving Seroprotection at Day 43 Based on Serum HAI Antibody Titers (≥1:40) to A/Astrakhan (H5N8).

The percentage of participants achieving seroprotection, defined as serum HAI antibody titer ≥ 1:40 against the H5N8 antigen. A titer of 1:40 or greater is considered to be a sufficient amount of antibody to avoid infection in half of exposed individuals.

Time frame:: Day 43
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroprotection at Day 43 Based on Serum HAI Antibody Titers (≥1:40) to A/Astrakhan (H5N8).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	87.5 (75.9 to 94.8)	89.8 (77.8 to 96.6)	96.0 (86.3 to 99.5)	87.3 (75.5 to 94.7)	81.1 (68.0 to 90.6)	81.1 (68.0 to 90.6)	57.1 (43.2 to 70.3)	75.4 (62.2 to 85.9)	66.7 (52.1 to 79.2)	8.0 (2.2 to 19.2)	1.9 (0.0 to 10.3)	—	2.0 (0.1 to 10.9)	7.3 (2.0 to 17.6)	—
> 65 years	—	86.8 (74.7 to 94.5)	80.4 (67.6 to 89.8)	—	78.0 (65.3 to 87.7)	78.6 (65.6 to 88.4)	—	52.8 (38.6 to 66.7)	63.2 (49.3 to 75.6)	—	11.9 (4.9 to 22.9)	20.0 (10.4 to 33.0)	—	6.8 (1.9 to 16.5)	3.4 (0.4 to 11.7)

SecondaryThe Percentage of Participants Who Experience Any Unsolicited Treatment-emergent Adverse Event (TEAE) Within 22 Days of Each Vaccination, Inclusive of the Vaccination Day.

The percentage of participants who experienced at least one unsolicited TEAE during at least one of the time frames specified. Unsolicited TEAEs were defined as any adverse event other than those included in the lists for solicited local and systemic reactions.

Time frame:: Day 1 through Day 22 and Day 22 through Day 43
Reported as:: Number · Percentage of Participants

The Percentage of Participants Who Experience Any Unsolicited Treatment-emergent Adverse Event (TEAE) Within 22 Days of Each Vaccination, Inclusive of the Vaccination Day.
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	27.9 (17.1 to 40.8)	23.0 (13.2 to 35.5)	21.3 (11.9 to 33.7)	28.3 (17.5 to 41.4)	28.3 (17.5 to 41.4)	18.3 (9.5 to 30.4)	40.0 (27.6 to 53.5)	25.0 (14.7 to 37.9)	18.6 (9.7 to 30.9)	20.0 (10.8 to 32.3)	17.2 (8.6 to 29.4)	—	21.7 (12.1 to 34.2)	16.7 (8.3 to 28.5)	—
>65 years	—	28.3 (17.5 to 41.4)	30.0 (18.8 to 43.2)	—	30.5 (19.2 to 43.9)	25.0 (14.7 to 37.9)	—	31.7 (20.3 to 45.0)	18.3 (9.5 to 30.4)	—	30.0 (18.8 to 43.2)	27.1 (16.4 to 40.3)	—	36.1 (24.2 to 49.4)	24.6 (14.5 to 37.3)
Overall	27.9 (17.1 to 40.8)	25.6 (18.1 to 34.4)	25.6 (18.1 to 34.4)	28.3 (17.5 to 41.4)	29.4 (21.4 to 38.5)	21.7 (14.7 to 30.1)	40.0 (27.6 to 53.5)	28.3 (20.5 to 37.3)	18.5 (12.0 to 26.6)	20.0 (10.8 to 32.3)	23.7 (16.4 to 32.4)	27.1 (16.4 to 40.3)	21.7 (12.1 to 34.2)	26.4 (18.8 to 35.2)	24.6 (14.5 to 37.3)

SecondaryThe Percentage of Participants Who Experience Any Treatment-emergent Serious Adverse Event (SAE).

The percentage of participants who experienced at least one treatment-emergent SAE during the time frame specified.

Time frame:: Day 1 through Day 203
Reported as:: Number · Percentage of Participants

The Percentage of Participants Who Experience Any Treatment-emergent Serious Adverse Event (SAE).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (0.0 to 6.0)	1.7 (0.0 to 8.9)	0 (0.0 to 6.0)	1.7 (0.0 to 8.9)	3.3 (0.4 to 11.5)	0 (0.0 to 6.1)	0 (NA to NA)	0 (NA to NA)	—	0 (0.0 to 6.0)	3.3 (0.4 to 11.5)	—
>65 years	—	1.7 (0.0 to 8.9)	1.7 (0.0 to 8.9)	—	1.7 (0.0 to 9.1)	1.7 (0.0 to 8.9)	—	8.3 (2.8 to 18.4)	1.7 (0.0 to 8.9)	—	1.7 (0.0 to 8.9)	1.7 (0.0 to 9.1)	—	0 (NA to NA)	0 (NA to NA)
Overall	0 (0.0 to 5.9)	0.8 (0.0 to 4.5)	0.8 (0.0 to 4.5)	0 (0.0 to 6.0)	1.7 (0.2 to 5.9)	0.8 (0.0 to 4.6)	1.7 (0.0 to 8.9)	5.8 (2.4 to 11.6)	0.8 (0.0 to 4.6)	0 (0.0 to 6.0)	0.8 (0.0 to 4.6)	1.7 (0.0 to 9.1)	0 (0.0 to 6.0)	1.7 (0.2 to 5.8)	0 (0.0 to 5.9)

SecondaryThe Percentage of Participants Who Experience Any Treatment-emergent Medically Attended Adverse Events (MAAE).

The percentage of participants who experienced at least one treatment-emergent MAAE during the time frame specified. MAAEs were defined as adverse events with medically attended visits including hospital, emergency room, urgent care clinic, or other visits to or from medical personnel for any reason.

Time frame:: Day 1 through Day 203
Reported as:: Number · Percentage of Participants

The Percentage of Participants Who Experience Any Treatment-emergent Medically Attended Adverse Events (MAAE).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	8.2 (2.7 to 18.1)	3.3 (0.4 to 11.3)	6.6 (1.8 to 15.9)	11.7 (4.8 to 22.6)	3.3 (0.4 to 11.5)	6.7 (1.8 to 16.2)	16.7 (8.3 to 28.5)	11.7 (4.8 to 22.6)	5.1 (1.1 to 14.1)	1.7 (0.0 to 8.9)	10.3 (3.9 to 21.2)	—	5.0 (1.0 to 13.9)	5.0 (1.0 to 13.9)	—
>65 years	—	6.7 (1.8 to 16.2)	15.0 (7.1 to 26.6)	—	8.5 (2.8 to 18.7)	13.3 (5.9 to 24.6)	—	23.3 (13.4 to 36.0)	5.0 (1.0 to 13.9)	—	8.3 (2.8 to 18.4)	11.9 (4.9 to 22.9)	—	13.1 (5.8 to 24.2)	3.3 (0.4 to 11.3)
Overall	8.2 (2.7 to 18.1)	5.0 (1.8 to 10.5)	10.7 (5.8 to 17.7)	11.7 (4.8 to 22.6)	5.9 (2.4 to 11.7)	10.0 (5.3 to 16.8)	16.7 (8.3 to 28.5)	17.5 (11.2 to 25.5)	5.0 (1.9 to 10.7)	1.7 (0.0 to 8.9)	9.3 (4.7 to 16.1)	11.9 (4.9 to 22.9)	5.0 (1.0 to 13.9)	9.1 (4.6 to 15.7)	3.3 (0.4 to 11.3)

SecondaryThe Percentage of Participants Who Experience Any Treatment-emergent Potentially Immune-mediated Disease (pIMD).

The percentage of participants who experienced at least one treatment-emergent pIMD during the time frame specified. A comprehensive list of adverse events to be reported as pIMDs is available in Appendix 3 of the Protocol.

Time frame:: Day 1 through Day 203
Reported as:: Number · Percentage of Participants

The Percentage of Participants Who Experience Any Treatment-emergent Potentially Immune-mediated Disease (pIMD).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	—	0 (NA to NA)	0 (NA to NA)	—
>65 Years	—	0 (NA to NA)	0 (NA to NA)	—	0 (NA to NA)	0 (NA to NA)	—	0 (NA to NA)	0 (NA to NA)	—	0 (NA to NA)	0 (NA to NA)	—	0 (NA to NA)	0 (NA to NA)
Overall	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)	0 (NA to NA)

SecondaryThe Percentage of Participants Achieving Seroprotection at Day 43 Based on Serum HAI Antibody Titers (≥1:40) to A/Bar-headed Goose (H5N1).

The percentage of participants achieving seroprotection, defined as serum HAI antibody titer ≥ 1:40 against the H5N1 antigen. A titer of 1:40 or greater is considered to be a sufficient amount of antibody to avoid infection in half of exposed individuals.

Time frame:: Day 43
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroprotection at Day 43 Based on Serum HAI Antibody Titers (≥1:40) to A/Bar-headed Goose (H5N1).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	8.9 (3.0 to 19.6)	16.3 (7.3 to 29.7)	8.0 (2.2 to 19.2)	3.6 (0.4 to 12.5)	5.7 (1.2 to 15.7)	22.6 (12.3 to 36.2)	8.9 (3.0 to 19.6)	7.0 (1.9 to 17.0)	5.9 (1.2 to 16.2)	84.0 (70.9 to 92.8)	86.5 (74.2 to 94.4)	—	59.2 (44.2 to 73.0)	65.5 (51.4 to 77.8)	—
>65 years	—	11.3 (4.3 to 23.0)	12.5 (5.2 to 24.1)	—	18.6 (9.7 to 30.9)	17.9 (8.9 to 30.4)	—	7.5 (2.1 to 18.2)	8.8 (2.9 to 19.3)	—	83.1 (71.0 to 91.6)	74.5 (61.0 to 85.3)	—	35.6 (23.6 to 49.1)	47.5 (34.3 to 60.9)

SecondarySerum HAI Antibody Titers to A/Astrakhan (H5N8) at Screening.

Serum HAI antibody titer levels against the H5N8 antigen. A higher HAI titer means a better immune response against the antigen.

Time frame:: Screening (i.e., pre-vaccination)
Reported as:: Geometric mean · Titers

Serum HAI Antibody Titers to A/Astrakhan (H5N8) at Screening.
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	5.39 (4.64 to 6.25)	5.48 (4.85 to 6.20)	5.07 (4.93 to 5.21)	5.00 (NA to NA)	5.00 (NA to NA)	5.97 (4.65 to 7.65)	5.00 (NA to NA)	5.00 (NA to NA)	5.00 (NA to NA)	5.00 (NA to NA)	5.00 (NA to NA)	—	5.00 (NA to NA)	5.50 (4.70 to 6.42)	—
>65 years	—	5.37 (4.65 to 6.21)	5.49 (4.75 to 6.34)	—	5.18 (4.92 to 5.46)	5.59 (4.74 to 6.59)	—	5.10 (4.90 to 5.30)	5.78 (4.92 to 6.80)	—	6.14 (4.96 to 7.60)	5.71 (4.88 to 6.67)	—	6.00 (5.00 to 7.19)	5.43 (5.02 to 5.87)

SecondarySerum HAI Antibody Titers to A/Astrakhan (H5N8) at Day 22.

Serum HAI antibody titer levels against the H5N8 antigen. A higher HAI titer means a better immune response against the antigen.

Time frame:: Day 22
Reported as:: Geometric mean · Titers

Serum HAI Antibody Titers to A/Astrakhan (H5N8) at Day 22.
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	30.84 (21.18 to 44.90)	58.60 (38.97 to 88.13)	42.87 (27.67 to 66.41)	40.50 (27.20 to 60.32)	35.78 (24.86 to 51.50)	37.22 (25.29 to 54.77)	21.01 (14.28 to 30.91)	25.29 (17.49 to 36.59)	23.22 (15.55 to 34.66)	5.68 (5.17 to 6.24)	6.27 (5.06 to 7.77)	—	6.18 (5.06 to 7.56)	6.30 (5.33 to 7.44)	—
>65 years	—	56.20 (37.30 to 84.67)	49.66 (33.30 to 74.06)	—	43.68 (28.47 to 67.02)	40.74 (27.89 to 59.52)	—	21.35 (14.65 to 31.11)	26.45 (17.96 to 38.96)	—	8.09 (6.43 to 10.19)	8.82 (6.79 to 11.44)	—	6.59 (5.56 to 7.81)	8.00 (6.12 to 10.46)

SecondarySerum HAI Antibody Titers to A/Astrakhan (H5N8) at Day 43.

Serum HAI antibody titer levels against the H5N8 antigen. A higher HAI titer means a better immune response against the antigen.

Time frame:: Day 43
Reported as:: Geometric mean · Titers

Serum HAI Antibody Titers to A/Astrakhan (H5N8) at Day 43.
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	173.40 (118.24 to 254.30)	200.63 (136.41 to 295.10)	191.60 (147.68 to 248.59)	132.44 (99.21 to 176.81)	107.37 (72.05 to 160.01)	91.77 (62.93 to 133.82)	47.57 (31.41 to 72.04)	76.65 (54.45 to 107.91)	60.96 (40.53 to 91.69)	7.17 (5.67 to 9.06)	5.83 (4.98 to 6.82)	—	5.56 (4.74 to 6.53)	7.21 (5.37 to 9.67)	—
>65 years	—	132.35 (93.01 to 188.34)	97.51 (66.17 to 143.70)	—	102.99 (71.24 to 148.88)	93.39 (64.70 to 134.80)	—	36.26 (24.46 to 53.75)	46.84 (33.20 to 66.09)	—	9.10 (6.63 to 12.49)	10.99 (7.82 to 15.45)	—	7.86 (6.14 to 10.05)	6.40 (5.33 to 7.68)

SecondarySerum HAI Antibody Titers to A/Astrakhan (H5N8) at Day 203.

Serum HAI antibody titer levels against the H5N8 antigen. A higher HAI titer means a better immune response against the antigen.

Time frame:: Day 203
Reported as:: Geometric mean · Titers

Serum HAI Antibody Titers to A/Astrakhan (H5N8) at Day 203.
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	59.22 (42.35 to 82.79)	70.25 (48.49 to 101.76)	67.98 (47.34 to 97.62)	47.23 (34.87 to 63.97)	45.00 (31.51 to 64.26)	48.86 (34.85 to 68.48)	23.09 (16.87 to 31.60)	31.67 (23.35 to 42.94)	28.29 (20.87 to 38.34)	5.74 (5.15 to 6.39)	7.17 (5.85 to 8.79)	—	5.71 (5.03 to 6.48)	5.65 (5.00 to 6.38)	—
≥65 years	—	49.80 (34.99 to 70.89)	62.27 (44.75 to 86.67)	—	47.14 (33.77 to 65.80)	49.30 (35.78 to 67.91)	—	16.76 (11.90 to 23.60)	28.46 (20.98 to 38.60)	—	9.00 (7.11 to 11.38)	9.04 (7.39 to 11.05)	—	8.67 (6.96 to 10.80)	9.00 (6.95 to 11.66)

SecondarySerum HAI Antibody Titers to A/Bar-headed Goose (H5N1) at Screening.

Serum HAI antibody titer levels against the H5N1 antigen. A higher HAI titer means a better immune response against the antigen.

Time frame:: Screening (i.e., pre-vaccination)
Reported as:: Geometric mean · Titers

Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1) at Screening.
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	5.06 (4.94 to 5.19)	5.64 (5.09 to 6.25)	5.18 (4.93 to 5.44)	5.13 (4.95 to 5.31)	5.07 (4.93 to 5.20)	5.56 (5.05 to 6.12)	5.06 (4.94 to 5.19)	5.06 (4.94 to 5.19)	5.14 (4.86 to 5.43)	5.14 (4.94 to 5.34)	5.07 (4.93 to 5.21)	—	5.22 (4.97 to 5.47)	5.13 (4.95 to 5.31)	—
≥65 years	—	5.85 (5.27 to 6.49)	6.17 (4.94 to 7.70)	—	5.79 (5.07 to 6.61)	6.29 (5.30 to 7.46)	—	5.81 (4.92 to 6.87)	5.79 (5.10 to 6.56)	—	7.54 (6.06 to 9.38)	6.17 (5.15 to 7.39)	—	6.03 (5.14 to 7.08)	6.25 (5.46 to 7.15)

SecondarySerum HAI Antibody Titers to A/Bar-headed Goose (H5N1) at Day 22.

Serum HAI antibody titer levels against the H5N1 antigen. A higher HAI titer means a better immune response against the antigen.

Time frame:: Day 22
Reported as:: Geometric mean · Titers

Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1) at Day 22.
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	9.46 (7.54 to 11.87)	9.93 (7.72 to 12.77)	9.79 (7.51 to 12.77)	8.87 (7.09 to 11.10)	10.26 (8.19 to 12.87)	16.11 (11.39 to 22.79)	10.25 (7.60 to 13.82)	9.05 (7.31 to 11.21)	11.69 (8.98 to 15.21)	20.43 (13.83 to 30.17)	24.58 (16.90 to 35.75)	—	15.29 (10.97 to 21.30)	16.18 (11.44 to 22.88)	—
≥65 years	—	11.85 (9.20 to 15.26)	10.12 (8.17 to 12.53)	—	13.02 (9.71 to 17.48)	15.80 (11.58 to 21.56)	—	8.06 (6.22 to 10.44)	10.06 (7.80 to 12.98)	—	32.95 (23.08 to 47.03)	31.68 (21.09 to 47.58)	—	15.72 (11.22 to 22.02)	20.83 (14.65 to 29.63)

SecondarySerum HAI Antibody Titers to A/Bar-headed Goose (H5N1) at Day 43.

Serum HAI antibody titer levels against the H5N1 antigen. A higher HAI titer means a better immune response against the antigen.

Time frame:: Day 43
Reported as:: Geometric mean · Titers

Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1) at Day 43.
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	10.06 (7.94 to 12.75)	12.72 (9.93 to 16.28)	11.49 (8.56 to 15.41)	7.97 (6.52 to 9.73)	9.68 (7.45 to 12.56)	14.70 (10.88 to 19.87)	8.84 (6.60 to 11.83)	8.33 (7.01 to 9.90)	9.09 (7.03 to 11.75)	122.95 (81.12 to 186.33)	124.19 (90.40 to 170.60)	—	43.22 (28.80 to 64.88)	51.13 (36.13 to 72.36)	—
≥65 years	—	11.10 (8.71 to 14.14)	11.04 (8.56 to 14.23)	—	13.33 (9.82 to 18.11)	13.79 (10.26 to 18.54)	—	8.27 (6.36 to 10.76)	8.59 (6.89 to 10.71)	—	101.78 (73.42 to 141.10)	79.49 (54.35 to 116.26)	—	23.30 (16.34 to 33.22)	27.62 (19.47 to 39.19)

SecondarySerum HAI Antibody Titers to A/Bar-headed Goose (H5N1) at Day 203

Serum HAI antibody titer levels against the H5N1 antigen. A higher HAI titer means a better immune response against the antigen.

Time frame:: Day 203
Reported as:: Geometric mean · Titers

Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1) at Day 203
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	8.16 (6.73 to 9.89)	7.88 (6.44 to 9.64)	7.80 (6.44 to 9.45)	6.20 (5.50 to 6.98)	6.83 (5.94 to 7.85)	8.35 (6.36 to 10.97)	6.67 (5.59 to 7.95)	6.00 (5.44 to 6.62)	6.59 (5.42 to 8.00)	30.61 (22.61 to 41.46)	36.48 (27.76 to 47.95)	—	14.03 (10.75 to 18.32)	13.85 (10.61 to 18.07)	—
≥65 years	—	8.74 (6.81 to 11.22)	8.74 (7.03 to 10.85)	—	9.43 (7.32 to 12.14)	10.20 (7.64 to 13.60)	—	6.41 (5.41 to 7.59)	7.25 (6.18 to 8.51)	—	39.76 (29.70 to 53.23)	33.32 (24.43 to 45.43)	—	15.23 (11.38 to 20.38)	12.73 (9.54 to 16.98)

SecondaryThe Percentage of Participants Achieving Seroprotection at Day 22 Based on Serum HAI Antibody Titers (≥1:40) to A/Astrakhan (H5N8).

Time frame:: Day 22
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroprotection at Day 22 Based on Serum HAI Antibody Titers (≥1:40) to A/Astrakhan (H5N8).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	42.9 (29.7 to 56.8)	69.4 (54.6 to 81.7)	54.0 (39.3 to 68.2)	54.5 (40.6 to 68.0)	52.8 (38.6 to 66.7)	54.7 (40.4 to 68.4)	28.6 (17.3 to 42.2)	37.5 (24.9 to 51.5)	35.3 (22.4 to 49.9)	0.0 (NA to NA)	3.8 (0.5 to 13.2)	—	6.1 (1.3 to 16.9)	3.7 (0.5 to 12.7)	—
≥65 years	—	60.4 (46.0 to 73.5)	57.1 (43.2 to 70.3)	—	54.2 (40.8 to 67.3)	53.6 (39.7 to 67.0)	—	37.7 (24.8 to 52.1)	38.6 (26.0 to 52.4)	—	8.5 (2.8 to 18.7)	12.7 (5.3 to 24.5)	—	1.7 (0.0 to 9.1)	10.2 (3.8 to 20.8)

SecondaryThe Percentage of Participants Achieving Seroprotection at Day 203 Based on Serum HAI Antibody Titers (≥1:40) to A/Astrakhan (H5N8).

Time frame:: Day 203
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroprotection at Day 203 Based on Serum HAI Antibody Titers (≥1:40) to A/Astrakhan (H5N8).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	64.2 (49.8 to 76.9)	70.8 (55.9 to 83.0)	77.6 (63.4 to 88.2)	60.0 (45.2 to 73.6)	60.0 (45.2 to 73.6)	55.8 (41.3 to 69.5)	34.0 (21.5 to 48.3)	43.6 (30.3 to 57.7)	38.8 (25.5 to 53.8)	0.0 (NA to NA)	2.0 (0.1 to 10.9)	—	2.1 (0.1 to 11.3)	2.0 (0.0 to 10.4)	—
≥65 years	—	63.3 (48.3 to 76.6)	61.1 (46.9 to 74.1)	—	59.3 (45.7 to 71.9)	60.4 (46.0 to 73.5)	—	28.3 (16.8 to 42.3)	38.2 (25.4 to 52.3)	—	8.5 (2.8 to 18.7)	5.5 (1.1 to 15.1)	—	7.1 (2.0 to 17.3)	14.3 (6.4 to 26.2)

SecondaryThe Percentage of Participants Achieving Seroprotection at Day 22 Based on Serum HAI Antibody Titers (≥1:40) to A/Bar-headed Goose (H5N1).

Time frame:: Day 22
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroprotection at Day 22 Based on Serum HAI Antibody Titers (≥1:40) to A/Bar-headed Goose (H5N1).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	10.7 (4.0 to 21.9)	10.2 (3.4 to 22.2)	10.0 (3.3 to 21.8)	7.3 (2.0 to 17.6)	9.4 (3.1 to 20.7)	20.8 (10.8 to 34.1)	12.5 (5.2 to 24.1)	8.9 (3.0 to 19.6)	17.6 (8.4 to 30.9)	28.6 (16.6 to 43.3)	36.5 (23.6 to 51.0)	—	22.4 (11.8 to 36.6)	22.2 (12.0 to 35.6)	—
≥65 years	—	15.1 (6.7 to 27.6)	10.7 (4.0 to 21.9)	—	16.9 (8.4 to 29.0)	19.6 (10.2 to 32.4)	—	7.5 (2.1 to 18.2)	12.3 (5.1 to 23.7)	—	44.1 (31.2 to 57.6)	47.3 (33.7 to 61.2)	—	23.7 (13.6 to 36.6)	35.6 (23.6 to 49.1)

SecondaryThe Percentage of Participants Achieving Seroprotection at Day 203 Based on Serum HAI Antibody Titers (≥1:40) to A/Bar-headed Goose (H5N1).

Time frame:: Day 203
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroprotection at Day 203 Based on Serum HAI Antibody Titers (≥1:40) to A/Bar-headed Goose (H5N1).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	3.8 (0.5 to 13.0)	6.3 (1.3 to 17.2)	2.0 (0.1 to 10.9)	0.0 (NA to NA)	0.0 (NA to NA)	9.6 (3.2 to 21.0)	3.8 (0.5 to 13.0)	0.0 (NA to NA)	2.0 (0.1 to 10.9)	47.9 (33.3 to 62.8)	57.1 (42.2 to 71.2)	—	19.1 (9.1 to 33.3)	19.6 (9.8 to 33.1)	—
≥65 years	—	12.2 (4.6 to 24.8)	5.6 (1.2 to 15.4)	—	10.2 (3.8 to 20.8)	9.4 (3.1 to 20.7)	—	3.8 (0.5 to 13.0)	1.8 (0.0 to 9.7)	—	52.5 (39.1 to 65.7)	52.7 (38.8 to 66.3)	—	19.6 (10.2 to 32.4)	21.4 (11.6 to 34.4)

SecondaryThe Percentage of Participants Achieving Seroconversion at Day 22 Based on Serum HAI Antibody Titers to A/Astrakhan (H5N8).

The percentage of participants achieving seroconversion, defined as either a pre-vaccination HAI antibody titer \<1:10 and a post-vaccination HAI titer ≥ 1:40, or a pre-vaccination HAI titer ≥1:10 and a minimum 4-fold rise in post-vaccination HAI titer against the H5N8 antigen. Seroconversion represents the minimum intended effect of vaccination.

Time frame:: Day 22
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroconversion at Day 22 Based on Serum HAI Antibody Titers to A/Astrakhan (H5N8).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	41.1 (28.1 to 55.0)	69.4 (54.6 to 81.7)	54.0 (39.3 to 68.2)	54.5 (40.6 to 68.0)	52.8 (38.6 to 66.7)	52.8 (38.6 to 66.7)	28.6 (17.3 to 42.2)	37.5 (24.9 to 51.5)	35.3 (22.4 to 49.9)	0.0 (NA to NA)	3.8 (0.5 to 13.2)	—	6.1 (1.3 to 16.9)	3.7 (0.5 to 12.7)	—
≥65 years	—	58.5 (44.1 to 71.9)	57.1 (43.2 to 70.3)	—	54.2 (40.8 to 67.3)	53.6 (39.7 to 67.0)	—	37.7 (24.8 to 52.1)	38.6 (26.0 to 52.4)	—	8.5 (2.8 to 18.7)	10.9 (4.1 to 22.2)	—	0.0 (NA to NA)	8.5 (2.8 to 18.7)

SecondaryThe Percentage of Participants Achieving Seroconversion at Day 43 Based on Serum HAI Antibody Titers to A/Astrakhan (H5N8).

Time frame:: Day 43
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroconversion at Day 43 Based on Serum HAI Antibody Titers to A/Astrakhan (H5N8).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	85.7 (73.8 to 93.6)	89.8 (77.8 to 96.6)	96.0 (86.3 to 99.5)	87.3 (75.5 to 94.7)	81.1 (68.0 to 90.6)	79.2 (65.9 to 89.2)	57.1 (43.2 to 70.3)	75.4 (62.2 to 85.9)	66.7 (52.1 to 79.2)	8.0 (2.2 to 19.2)	1.9 (0.0 to 10.3)	—	2.0 (0.1 to 10.9)	7.3 (2.0 to 17.6)	—
≥65 years	—	86.8 (74.7 to 94.5)	80.4 (67.6 to 89.8)	—	78.0 (65.3 to 87.7)	76.8 (63.6 to 87.0)	—	52.8 (38.6 to 66.7)	61.4 (47.6 to 74.0)	—	11.9 (4.9 to 22.9)	18.2 (9.1 to 30.9)	—	5.1 (1.1 to 14.1)	3.4 (0.4 to 11.7)

SecondaryThe Percentage of Participants Achieving Seroconversion at Day 203 Based on Serum HAI Antibody Titers to A/Astrakhan (H5N8).

Time frame:: Day 203
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroconversion at Day 203 Based on Serum HAI Antibody Titers to A/Astrakhan (H5N8).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	62.3 (47.9 to 75.2)	70.8 (55.9 to 83.0)	77.6 (63.4 to 88.2)	60.0 (45.2 to 73.6)	60.0 (45.2 to 73.6)	53.8 (39.5 to 67.8)	34.0 (21.5 to 48.3)	43.6 (30.3 to 57.7)	38.8 (25.2 to 53.8)	0 (NA to NA)	2.0 (0.1 to 10.9)	—	2.1 (0.1 to 11.3)	2.0 (0.0 to 10.4)	—
≥65 years	—	61.2 (46.2 to 74.8)	61.1 (46.9 to 74.1)	—	59.3 (45.7 to 71.9)	60.4 (46.0 to 73.5)	—	26.4 (15.3 to 40.3)	36.4 (23.8 to 50.4)	—	8.5 (2.8 to 18.7)	5.5 (1.1 to 15.1)	—	3.6 (0.4 to 12.3)	12.5 (5.2 to 24.1)

SecondaryThe Percentage of Participants Achieving Seroconversion at Day 22 Based on Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1).

The percentage of participants achieving seroconversion, defined as either a pre-vaccination HAI antibody titer \<1:10 and a post-vaccination HAI titer ≥ 1:40, or a pre-vaccination HAI titer ≥1:10 and a minimum 4-fold rise in post-vaccination HAI titer against the H5N1 antigen. Seroconversion represents the minimum intended effect of vaccination.

Time frame:: Day 22
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroconversion at Day 22 Based on Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	10.7 (4.0 to 21.9)	6.1 (1.3 to 16.9)	10.0 (3.3 to 21.8)	7.3 (2.0 to 17.6)	9.4 (3.1 to 20.7)	20.8 (10.8 to 34.1)	12.5 (5.2 to 24.1)	8.9 (3.0 to 19.6)	17.6 (8.4 to 30.9)	28.6 (16.6 to 43.3)	36.5 (23.6 to 51.0)	—	22.4 (11.8 to 36.6)	22.2 (12.0 to 35.6)	—
≥65 years	—	13.2 (5.5 to 25.3)	7.1 (2.0 to 17.3)	—	13.6 (6.0 to 25.0)	16.1 (7.6 to 28.3)	—	5.7 (1.2 to 15.7)	8.8 (2.9 to 19.3)	—	40.7 (28.1 to 54.3)	45.5 (32.0 to 59.4)	—	22.0 (12.3 to 34.7)	35.6 (23.6 to 49.1)

SecondaryThe Percentage of Participants Achieving Seroconversion at Day 43 Based on Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1).

The percentage of participants achieving seroconversion, defined as either a pre-vaccination HAI antibody titer \<1:10 and a post-vaccination HAI titer ≥ 1:40, or a pre-vaccination HAI titer ≥1:10 and a minimum 4-fold rise in post-vaccination HAI titer against the H5N1 antigen. Seroconversion represents the minimum intended effect of vaccination.

Time frame:: Day 43
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroconversion at Day 43 Based on Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	8.9 (3.0 to 19.6)	14.3 (5.9 to 27.2)	8.0 (2.2 to 19.2)	3.6 (0.4 to 12.5)	5.7 (1.2 to 15.7)	22.6 (12.3 to 36.2)	8.9 (3.0 to 19.6)	7.0 (1.9 to 17.0)	5.9 (1.2 to 16.2)	84.0 (70.9 to 92.8)	84.6 (71.9 to 93.1)	—	59.2 (44.2 to 73.0)	65.5 (51.4 to 77.8)	—
≥65 years	—	9.4 (3.1 to 20.7)	10.7 (4.0 to 21.9)	—	15.3 (7.2 to 27.0)	14.3 (6.4 to 26.2)	—	5.7 (1.2 to 15.7)	7.0 (1.9 to 17.0)	—	79.7 (67.2 to 89.0)	70.9 (57.1 to 82.4)	—	33.9 (22.1 to 47.4)	44.1 (31.2 to 57.6)

SecondaryThe Percentage of Participants Achieving Seroconversion at Day 203 Based on Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1).

The percentage of participants achieving seroconversion, defined as either a pre-vaccination HAI antibody titer \<1:10 and a post-vaccination HAI titer ≥ 1:40, or a pre-vaccination HAI titer ≥1:10 and a minimum 4-fold rise in post-vaccination HAI titer against the H5N1 antigen. Seroconversion represents the minimum intended effect of vaccination.

Time frame:: Day 203
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroconversion at Day 203 Based on Serum HAI Antibody Titers to A/Bar-headed Goose (H5N1).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	3.8 (0.5 to 13.0)	2.1 (0.1 to 11.1)	2.0 (0.1 to 10.9)	0 (NA to NA)	0 (NA to NA)	7.7 (2.1 to 18.5)	3.8 (0.5 to 13.0)	0 (NA to NA)	2.0 (0.1 to 10.9)	47.9 (33.3 to 62.8)	55.1 (40.2 to 69.3)	—	19.1 (9.1 to 33.3)	19.6 (9.8 to 33.1)	—
≥65 years	—	10.2 (3.4 to 22.2)	3.7 (0.5 to 12.7)	—	8.5 (2.8 to 18.7)	7.5 (2.1 to 18.2)	—	0 (NA to NA)	1.8 (0.0 to 9.7)	—	45.8 (32.7 to 59.2)	47.3 (33.7 to 61.2)	—	16.1 (7.6 to 28.3)	17.9 (8.9 to 30.4)

SecondarySerum MN Antibody Titers to A/Astrakhan (H5N8) at Screening.

Serum MN antibody titer levels against the H5N8 antigen. A higher MN titer means a better immune response against the antigen.

Time frame:: Screening (i.e., pre-vaccination)
Reported as:: Geometric mean · Titers

Serum MN Antibody Titers to A/Astrakhan (H5N8) at Screening.
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	5.35 (4.67 to 6.13)	5.22 (4.97 to 5.47)	5.25 (4.87 to 5.65)	5.00 (NA to NA)	5.34 (4.68 to 6.09)	5.55 (4.50 to 6.85)	5.13 (4.88 to 5.39)	5.06 (4.94 to 5.19)	5.07 (4.93 to 5.21)	5.00 (NA to NA)	5.00 (NA to NA)	—	5.00 (NA to NA)	5.00 (NA to NA)	—
≥65 years	—	5.41 (4.81 to 6.08)	5.49 (4.89 to 6.16)	—	5.00 (NA to NA)	5.13 (4.95 to 5.31)	—	5.00 (NA to NA)	5.28 (4.84 to 5.77)	—	5.37 (4.83 to 5.96)	5.19 (4.81 to 5.60)	—	5.40 (4.93 to 5.91)	5.86 (4.86 to 7.06)

SecondarySerum MN Antibody Titers to A/Astrakhan (H5N8) at Day 22.

Serum MN antibody titer levels against the H5N8 antigen. A higher MN titer means a better immune response against the antigen.

Time frame:: Day 22
Reported as:: Geometric mean · Titers

Serum MN Antibody Titers to A/Astrakhan (H5N8) at Day 22.
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	34.96 (22.40 to 54.55)	41.77 (28.26 to 61.75)	38.10 (24.59 to 59.03)	27.58 (19.09 to 39.84)	23.70 (16.19 to 34.69)	21.40 (14.37 to 31.89)	15.23 (10.23 to 22.69)	21.28 (14.25 to 31.77)	14.24 (9.61 to 21.09)	5.14 (4.94 to 5.35)	5.49 (4.55 to 6.62)	—	5.00 (NA to NA)	5.00 (NA to NA)	—
≥65 years	—	17.74 (13.22 to 23.80)	29.71 (19.53 to 45.19)	—	18.42 (12.68 to 26.75)	22.12 (14.52 to 33.69)	—	10.20 (7.30 to 14.25)	12.89 (8.88 to 18.71)	—	5.62 (4.77 to 6.63)	6.81 (5.24 to 8.85)	—	5.40 (4.63 to 6.29)	5.93 (4.88 to 7.21)

SecondarySerum MN Antibody Titers to A/Astrakhan (H5N8) at Day 43.

Serum MN antibody titer levels against the H5N8 antigen. A higher MN titer means a better immune response against the antigen.

Time frame:: Day 43
Reported as:: Geometric mean · Titers

Serum MN Antibody Titers to A/Astrakhan (H5N8) at Day 43.
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	433.35 (330.18 to 568.78)	492.63 (362.09 to 670.22)	331.29 (250.70 to 437.79)	269.09 (198.33 to 365.10)	203.79 (136.32 to 304.65)	198.53 (144.05 to 273.62)	84.04 (54.11 to 130.52)	129.33 (92.34 to 181.14)	111.57 (74.17 to 167.83)	6.07 (4.83 to 7.63)	5.53 (4.64 to 6.59)	—	5.29 (4.72 to 5.93)	5.46 (4.69 to 6.37)	—
≥65 years	—	211.92 (147.29 to 304.93)	148.53 (99.21 to 222.37)	—	179.95 (125.02 to 259.01)	162.00 (118.10 to 222.22)	—	51.86 (33.39 to 80.55)	60.84 (40.71 to 90.94)	—	6.55 (5.13 to 8.37)	8.12 (5.75 to 11.47)	—	5.46 (4.72 to 6.31)	6.07 (4.84 to 7.61)

SecondarySerum MN Antibody Titers to A/Astrakhan (H5N8) at Day 203.

Serum MN antibody titer levels against the H5N8 antigen. A higher MN titer means a better immune response against the antigen.

Time frame:: Day 203
Reported as:: Geometric mean · Titers

Serum MN Antibody Titers to A/Astrakhan (H5N8) at Day 203.
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	34.19 (25.08 to 46.60)	41.47 (28.75 to 59.81)	46.74 (33.23 to 65.75)	27.13 (19.60 to 37.55)	29.08 (19.77 to 42.77)	30.23 (21.86 to 41.81)	16.76 (12.13 to 23.15)	21.18 (16.15 to 27.78)	16.06 (11.67 to 22.09)	5.07 (4.93 to 5.22)	5.33 (4.81 to 5.91)	—	5.00 (NA to NA)	5.21 (4.80 to 5.65)	—
≥65 years	—	25.61 (19.42 to 33.76)	31.81 (22.84 to 44.32)	—	29.47 (21.58 to 40.24)	27.37 (19.16 to 39.10)	—	11.85 (8.60 to 16.34)	13.79 (10.51 to 18.09)	—	5.76 (4.94 to 6.71)	5.78 (4.98 to 6.70)	—	5.59 (4.69 to 6.67)	5.76 (4.96 to 6.70)

SecondarySerum MN Antibody Titers to A/Bar-headed Goose (H5N1) at Screening.

Serum MN antibody titer levels against the H5N1 antigen. A higher MN titer means a better immune response against the antigen.

Time frame:: Screening (i.e., pre-vaccination)
Reported as:: Geometric mean · Titers

Serum MN Antibody Titers to A/Bar-headed Goose (H5N1) at Screening.
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	5.49 (5.01 to 6.01)	6.14 (5.05 to 7.46)	5.78 (5.08 to 6.58)	5.29 (4.95 to 5.66)	5.17 (4.93 to 5.41)	5.74 (4.95 to 6.64)	5.52 (4.95 to 6.15)	5.06 (4.94 to 5.19)	5.39 (4.92 to 5.90)	5.36 (4.92 to 5.83)	5.54 (5.09 to 6.02)	—	5.22 (4.97 to 5.47)	5.64 (5.04 to 6.30)	—
≥65 years	—	6.49 (5.37 to 7.85)	7.25 (5.70 to 9.21)	—	6.14 (5.33 to 7.08)	6.65 (5.58 to 7.91)	—	5.89 (5.08 to 6.82)	6.21 (5.35 to 7.21)	—	7.29 (5.77 to 9.19)	7.92 (6.13 to 10.23)	—	6.21 (4.99 to 7.74)	6.71 (5.33 to 8.44)

SecondarySerum MN Antibody Titers to A/Bar-headed Goose (H5N1) at Day 22.

Serum MN antibody titer levels against the H5N1 antigen. A higher MN titer means a better immune response against the antigen.

Time frame:: Day 22
Reported as:: Geometric mean · Titers

Serum MN Antibody Titers to A/Bar-headed Goose (H5N1) at Day 22.
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	7.72 (5.89 to 10.14)	8.23 (6.20 to 10.91)	9.52 (6.96 to 13.04)	7.30 (5.78 to 9.21)	7.80 (6.45 to 9.43)	11.22 (7.44 to 16.93)	8.49 (5.85 to 12.31)	7.44 (5.98 to 9.24)	7.37 (5.40 to 10.05)	19.44 (12.43 to 30.39)	30.03 (18.79 to 47.98)	—	11.52 (8.50 to 15.61)	14.23 (9.84 to 20.58)	—
≥65 years	—	8.49 (6.67 to 10.81)	10.25 (7.74 to 13.57)	—	11.86 (8.47 to 16.60)	12.73 (9.09 to 17.83)	—	7.45 (5.78 to 9.60)	10.37 (7.43 to 14.48)	—	36.41 (22.17 to 59.77)	41.54 (24.63 to 70.07)	—	13.18 (8.88 to 19.56)	19.53 (12.76 to 29.89)

SecondarySerum MN Antibody Titers to A/Bar-headed Goose (H5N1) at Day 43.

Serum MN antibody titer levels against the H5N1 antigen. A higher MN titer means a better immune response against the antigen.

Time frame:: Day 43
Reported as:: Geometric mean · Titers

Serum MN Antibody Titers to A/Bar-headed Goose (H5N1) at Day 43.
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	16.70 (11.95 to 23.35)	18.89 (13.53 to 26.39)	13.95 (10.16 to 19.15)	10.26 (8.05 to 13.06)	11.78 (8.43 to 16.44)	17.43 (11.40 to 26.65)	12.04 (8.28 to 17.51)	8.96 (7.27 to 11.04)	8.55 (6.23 to 11.74)	294.45 (196.45 to 441.33)	311.57 (217.39 to 446.55)	—	77.21 (49.66 to 120.02)	106.22 (72.43 to 155.80)	—
≥65 years	—	14.80 (10.78 to 20.32)	16.41 (11.99 to 22.45)	—	18.72 (12.86 to 27.25)	24.99 (16.51 to 37.83)	—	10.67 (7.89 to 14.44)	12.00 (8.54 to 16.87)	—	251.51 (168.45 to 375.53)	219.26 (143.42 to 335.21)	—	44.54 (30.59 to 64.84)	57.24 (37.21 to 88.04)

SecondarySerum MN Antibody Titers to A/Bar-headed Goose (H5N1) at Day 203.

Serum MN antibody titer levels against the H5N1 antigen. A higher MN titer means a better immune response against the antigen.

Time frame:: Day 203
Reported as:: Geometric mean · Titers

Serum MN Antibody Titers to A/Bar-headed Goose (H5N1) at Day 203.
Titers	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	10.40 (8.05 to 13.42)	14.24 (10.33 to 19.62)	12.19 (9.20 to 16.15)	7.74 (6.54 to 9.16)	8.95 (7.46 to 10.73)	12.21 (8.92 to 16.71)	9.23 (6.84 to 12.46)	7.58 (6.34 to 9.06)	7.97 (6.22 to 10.21)	61.24 (44.33 to 84.61)	78.88 (54.54 to 114.10)	—	27.25 (19.72 to 37.66)	30.89 (22.65 to 42.12)	—
≥65 years	—	12.36 (9.46 to 16.14)	12.76 (9.44 to 17.24)	—	11.31 (8.69 to 14.73)	15.60 (11.05 to 22.03)	—	8.60 (6.80 to 10.88)	9.81 (7.69 to 12.52)	—	70.30 (49.17 to 100.49)	85.20 (60.31 to 120.36)	—	25.14 (18.45 to 34.25)	25.45 (18.74 to 34.57)

SecondaryThe Percentage of Participants Achieving Seroconversion at Day 22 Based on Serum MN Antibody Titers to A/Astrakhan (H5N8).

The percentage of participants achieving seroconversion, defined as either a pre-vaccination MN antibody titer \<1:10 and a post-vaccination MN titer ≥ 1:40, or a pre-vaccination MN titer ≥1:10 and a minimum 4-fold rise in post-vaccination MN titer against the H5N8 antigen. Seroconversion represents the minimum intended effect of vaccination.

Time frame:: Day 22
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroconversion at Day 22 Based on Serum MN Antibody Titers to A/Astrakhan (H5N8).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	50.0 (36.1 to 63.9)	56.3 (41.2 to 70.5)	46.0 (31.8 to 60.7)	45.5 (32.0 to 59.4)	35.8 (23.1 to 50.2)	27.5 (15.9 to 41.7)	23.2 (13.0 to 36.4)	30.4 (18.8 to 44.1)	17.6 (8.4 to 30.9)	0 (NA to NA)	1.9 (0.0 to 10.3)	—	0 (NA to NA)	0 (NA to NA)	—
≥65 years	—	21.2 (11.1 to 34.7)	42.9 (29.7 to 56.8)	—	27.1 (16.4 to 40.3)	34.5 (22.2 to 48.6)	—	9.4 (3.1 to 20.7)	19.6 (10.2 to 32.4)	—	1.7 (0.0 to 9.1)	7.3 (2.0 to 17.6)	—	1.7 (0.0 to 9.1)	1.7 (0.0 to 9.1)

SecondaryThe Percentage of Participants Achieving Seroconversion at Day 43 Based on Serum MN Antibody Titers to A/Astrakhan (H5N8).

Time frame:: Day 43
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroconversion at Day 43 Based on Serum MN Antibody Titers to A/Astrakhan (H5N8).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	96.4 (87.7 to 99.6)	95.9 (86.0 to 99.5)	96.0 (86.3 to 99.5)	94.4 (84.6 to 98.8)	83.0 (70.2 to 91.9)	92.5 (81.8 to 97.9)	62.5 (48.5 to 75.1)	84.2 (72.1 to 92.5)	82.0 (68.6 to 91.4)	6.0 (1.3 to 16.5)	1.9 (0.0 to 10.3)	—	2.0 (0.1 to 10.9)	1.8 (0.0 to 9.7)	—
≥65 years	—	88.7 (77.0 to 95.7)	80.4 (67.6 to 89.8)	—	86.4 (75.0 to 94.0)	91.1 (80.4 to 97.0)	—	57.7 (43.2 to 71.3)	61.4 (47.6 to 74.0)	—	3.4 (0.4 to 11.7)	10.9 (4.1 to 22.2)	—	1.7 (0.0 to 9.1)	1.7 (0.0 to 9.1)

SecondaryThe Percentage of Participants Achieving Seroconversion at Day 203 Based on Serum MN Antibody Titers to A/Astrakhan (H5N8).

Time frame:: Day 203
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroconversion at Day 203 Based on Serum MN Antibody Titers to A/Astrakhan (H5N8).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	52.8 (38.6 to 66.7)	54.2 (39.2 to 68.6)	59.2 (44.2 to 73.0)	38.0 (24.7 to 52.8)	46.0 (31.8 to 60.7)	42.3 (28.7 to 56.8)	28.3 (16.8 to 42.3)	33.3 (21.1 to 47.5)	18.4 (8.8 to 32.0)	0 (NA to NA)	2.0 (0.1 to 10.9)	—	0 (NA to NA)	2.0 (0.0 to 10.4)	—
≥65 years	—	42.9 (28.8 to 57.8)	49.1 (35.1 to 63.2)	—	42.4 (29.6 to 55.9)	43.4 (29.8 to 57.7)	—	18.9 (9.4 to 32.0)	20.0 (10.4 to 33.0)	—	1.7 (0.0 to 9.1)	1.8 (0.0 to 9.7)	—	1.8 (0.0 to 9.6)	0 (NA to NA)

SecondaryThe Percentage of Participants Achieving Seroconversion at Day 22 Based on Serum MN Antibody Titers to A/Bar-headed Goose (H5N1).

The percentage of participants achieving seroconversion, defined as either a pre-vaccination MN antibody titer \<1:10 and a post-vaccination MN titer ≥ 1:40, or a pre-vaccination MN titer ≥1:10 and a minimum 4-fold rise in post-vaccination MN titer against the H5N1 antigen. Seroconversion represents the minimum intended effect of vaccination.

Time frame:: Day 22
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroconversion at Day 22 Based on Serum MN Antibody Titers to A/Bar-headed Goose (H5N1).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	7.3 (2.0 to 17.6)	6.3 (1.3 to 17.2)	6.0 (1.3 to 16.5)	5.5 (1.1 to 15.1)	3.8 (0.5 to 13.0)	13.7 (5.7 to 26.3)	9.1 (3.0 to 20.0)	3.6 (0.4 to 12.5)	5.9 (1.2 to 16.2)	30.6 (18.3 to 45.4)	36.5 (23.6 to 51.0)	—	12.2 (4.6 to 24.8)	18.9 (9.4 to 32.0)	—
≥65 years	—	5.7 (1.3 to 15.7)	7.1 (2.0 to 17.3)	—	15.3 (7.2 to 27.0)	16.1 (7.6 to 28.3)	—	1.9 (0.0 to 10.1)	7.0 (1.9 to 17.0)	—	39.0 (26.5 to 52.6)	47.3 (33.7 to 61.2)	—	13.6 (6.0 to 25.0)	27.6 (16.7 to 40.9)

SecondaryThe Percentage of Participants Achieving Seroconversion at Day 43 Based on Serum MN Antibody Titers to A/Bar-headed Goose (H5N1).

The percentage of participants achieving seroconversion, defined as either a pre-vaccination MN antibody titer \<1:10 and a post-vaccination MN titer ≥ 1:40, or a pre-vaccination MN titer ≥1:10 and a minimum 4-fold rise in post-vaccination MN titer against the H5N1 antigen. Seroconversion represents the minimum intended effect of vaccination.

Time frame:: Day 43
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroconversion at Day 43 Based on Serum MN Antibody Titers to A/Bar-headed Goose (H5N1).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	25.9 (15.0 to 39.7)	14.3 (5.9 to 27.2)	18.0 (8.6 to 31.4)	9.3 (3.1 to 20.3)	18.9 (9.4 to 32.0)	20.8 (10.8 to 34.1)	16.1 (7.6 to 28.3)	8.8 (2.9 to 19.3)	3.9 (0.5 to 13.5)	94.0 (83.5 to 98.7)	94.2 (84.1 to 98.8)	—	71.4 (56.7 to 83.4)	74.5 (61.0 to 85.3)	—
≥65 years	—	22.6 (12.3 to 36.2)	12.5 (5.2 to 24.1)	—	24.1 (13.9 to 37.2)	25.0 (14.4 to 38.4)	—	7.5 (2.1 to 18.2)	14.0 (6.3 to 25.8)	—	89.8 (79.2 to 96.2)	89.1 (77.8 to 95.9)	—	53.4 (39.9 to 66.7)	61.0 (47.4 to 73.5)

SecondaryThe Percentage of Participants Achieving Seroconversion at Day 203 Based on Serum MN Antibody Titers to A/Bar-headed Goose (H5N1).

The percentage of participants achieving seroconversion, defined as either a pre-vaccination MN antibody titer \<1:10 and a post-vaccination MN titer ≥ 1:40, or a pre-vaccination MN titer ≥1:10 and a minimum 4-fold rise in post-vaccination MN titer against the H5N1 antigen. Seroconversion represents the minimum intended effect of vaccination.

Time frame:: Day 203
Reported as:: Number · Percentage of Participants

The Percentage of Participants Achieving Seroconversion at Day 203 Based on Serum MN Antibody Titers to A/Bar-headed Goose (H5N1).
Percentage of Participants	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
18-64 years	11.3 (4.3 to 23.0)	12.5 (4.7 to 25.2)	10.2 (3.4 to 22.2)	0 (NA to NA)	2.0 (0.1 to 10.6)	11.5 (4.4 to 23.4)	9.6 (3.2 to 21.0)	5.5 (1.1 to 15.1)	2.0 (0.1 to 10.9)	66.7 (51.6 to 79.6)	77.6 (63.4 to 88.2)	—	48.9 (34.1 to 63.9)	43.1 (29.3 to 57.8)	—
≥65 years	—	6.1 (1.3 to 16.9)	9.3 (3.1 to 20.3)	—	10.2 (3.8 to 20.8)	17.0 (8.1 to 29.8)	—	3.8 (0.5 to 13.0)	5.5 (1.1 to 15.1)	—	64.4 (50.9 to 76.4)	76.4 (63.0 to 86.8)	—	32.1 (20.3 to 46.0)	32.1 (20.3 to 46.0)

Adverse events

Collected over From receipt of the first vaccination until exit from the study, which was planned to occur 202 days after the date of initial vaccination.. Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
Group	Deaths	Serious	Other
3.75 µg H5N8 Plus AS03A Full Dose	0/61 (0%)	0/61 (0%)	46/61 (75.4%)
7.5 µg H5N8 Plus AS03A Full Dose	0/121 (0%)	1/121 (0.8%)	77/121 (63.6%)
15 µg H5N8 Plus AS03A Full Dose	0/121 (0%)	1/121 (0.8%)	74/121 (61.2%)
3.75 µg H5N8 Plus AS03A Half Dose	0/60 (0%)	0/60 (0%)	31/60 (51.7%)
7.5 µg H5N8 Plus AS03A Half Dose	0/119 (0%)	2/119 (1.7%)	73/119 (61.3%)
15 µg H5N8 Plus AS03A Half Dose	0/120 (0%)	1/120 (0.8%)	75/120 (62.5%)
3.75 µg H5N8 Plus MF59	0/60 (0%)	1/60 (1.7%)	38/60 (63.3%)
7.5 µg H5N8 Plus MF59	0/120 (0%)	7/120 (5.8%)	52/120 (43.3%)
15 µg H5N8 Plus MF59	0/119 (0%)	1/119 (0.8%)	43/119 (36.1%)
3.75 µg H5N1 Plus AS03A Full Dose	0/60 (0%)	0/60 (0%)	45/60 (75%)
7.5 µg H5N1 Plus AS03A Full Dose	0/118 (0%)	1/118 (0.8%)	79/118 (66.9%)
15 µg H5N1 Plus AS03A Full Dose	0/59 (0%)	1/59 (1.7%)	35/59 (59.3%)
3.75 µg H5N1 Plus MF59	0/60 (0%)	0/60 (0%)	33/60 (55%)
7.5 µg H5N1 Plus MF59	0/121 (0%)	2/121 (1.7%)	53/121 (43.8%)
15 µg H5N1 Plus MF59	0/61 (0%)	0/61 (0%)	27/61 (44.3%)

Most frequent serious events

Showing 10 of 17

Most frequent serious events
Event	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
Intracranial massNervous system disorders	0/61	0/121	0/121	0/60	0/119	0/120	0/60	0/120	0/119	0/60	0/118	1/59	0/60	0/121	0/61
Wound infectionInfections and infestations	0/61	0/121	0/121	0/60	0/119	0/120	1/60	0/120	0/119	0/60	0/118	0/59	0/60	0/121	0/61
Ankle fractureInjury, poisoning and procedural complications	0/61	0/121	0/121	0/60	0/119	0/120	0/60	2/120	0/119	0/60	0/118	0/59	0/60	0/121	0/61
Myocardial infarctionCardiac disorders	0/61	0/121	0/121	0/60	0/119	0/120	0/60	0/120	1/119	0/60	1/118	0/59	0/60	0/121	0/61
HaematemesisGastrointestinal disorders	0/61	0/121	0/121	0/60	1/119	0/120	0/60	0/120	0/119	0/60	0/118	0/59	0/60	0/121	0/61
Acute kidney injuryRenal and urinary disorders	0/61	0/121	0/121	0/60	1/119	0/120	0/60	0/120	0/119	0/60	0/118	0/59	0/60	0/121	0/61
PneumoniaInfections and infestations	0/61	0/121	0/121	0/60	0/119	1/120	0/60	0/120	0/119	0/60	0/118	0/59	0/60	0/121	0/61
Hip fractureInjury, poisoning and procedural complications	0/61	0/121	0/121	0/60	0/119	0/120	0/60	1/120	0/119	0/60	0/118	0/59	0/60	0/121	0/61
Back painMusculoskeletal and connective tissue disorders	0/61	0/121	0/121	0/60	0/119	0/120	0/60	1/120	0/119	0/60	0/118	0/59	0/60	0/121	0/61
Lung carcinoma cell type unspecified stage IVNeoplasms benign, malignant and unspecified (incl cysts and polyps)	0/61	0/121	0/121	0/60	0/119	1/120	0/60	0/120	0/119	0/60	0/118	0/59	0/60	0/121	0/61

Most frequent other events

Showing 10 of 14

Most frequent other events
Event	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59
Injection site painGeneral disorders	37/61	57/121	53/121	23/60	57/119	52/120	28/60	33/120	28/119	36/60	65/118	25/59	18/60	28/121	19/61
MyalgiaMusculoskeletal and connective tissue disorders	20/61	38/121	33/121	9/60	23/119	30/120	15/60	13/120	8/119	17/60	30/118	8/59	7/60	13/121	4/61
FatigueGeneral disorders	18/61	32/121	26/121	16/60	28/119	24/120	15/60	22/120	12/119	17/60	33/118	10/59	10/60	21/121	5/61
HeadacheNervous system disorders	14/61	32/121	21/121	14/60	22/119	27/120	17/60	19/120	9/119	13/60	22/118	7/59	12/60	15/121	5/61
ArthralgiaMusculoskeletal and connective tissue disorders	14/61	14/121	12/121	4/60	14/119	6/120	7/60	9/120	1/119	4/60	12/118	3/59	5/60	6/121	2/61
Injection site indurationGeneral disorders	13/61	19/121	14/121	4/60	15/119	11/120	7/60	4/120	5/119	10/60	21/118	9/59	4/60	7/121	3/61
ChillsGeneral disorders	10/61	20/121	15/121	2/60	10/119	9/120	1/60	8/120	2/119	5/60	9/118	3/59	2/60	4/121	3/61
NauseaGastrointestinal disorders	9/61	10/121	10/121	3/60	5/119	8/120	3/60	4/120	2/119	5/60	6/118	2/59	4/60	5/121	0/61
Injection site erythemaGeneral disorders	9/61	11/121	16/121	5/60	14/119	12/120	4/60	4/120	3/119	8/60	16/118	8/59	4/60	5/121	4/61
DiarrhoeaGastrointestinal disorders	6/61	13/121	8/121	4/60	6/119	9/120	3/60	12/120	4/119	5/60	9/118	0/59	7/60	9/121	3/61

Baseline characteristics

The safety population included all participants who were randomized and received at least one vaccination.

Age, Categorical
Age, Categorical(Participants)	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59	Total
<=18 years	0	0	1	1	0	0	0	0	0	0	0	0	1	0	0	3
Between 18 and 65 years	61	61	60	59	60	60	60	60	59	60	58	0	59	60	0	777
>=65 years	0	60	60	0	59	60	0	60	60	0	60	59	0	61	61	600

Age, Continuous
Age, Continuous(years)	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59	Total
Mean	47.0 ± 11.81	58.7 ± 16.59	57.4 ± 17.02	47.5 ± 11.76	59.0 ± 16.79	57.8 ± 17.41	42.6 ± 13.13	60.5 ± 16.34	59.6 ± 15.74	43.0 ± 12.95	59.2 ± 14.92	71.4 ± 4.62	46.1 ± 12.80	58.9 ± 16.34	71.2 ± 4.80	57.0 ± 16.53

Sex: Female, Male
Sex: Female, Male(Participants)	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59	Total
Female	37	58	62	34	68	62	27	62	63	33	61	33	36	67	33	736
Male	24	63	59	26	51	58	33	58	56	27	57	26	24	54	28	644

Ethnicity (NIH/OMB)
Ethnicity (NIH/OMB)(Participants)	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59	Total
Hispanic or Latino	8	10	8	9	9	10	11	15	9	4	6	0	6	8	4	117
Not Hispanic or Latino	52	109	111	51	107	107	47	102	106	55	110	59	53	112	55	1236
Unknown or Not Reported	1	2	2	0	3	3	2	3	4	1	2	0	1	1	2	27

Race (NIH/OMB)
Race (NIH/OMB)(Participants)	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59	Total
American Indian or Alaska Native	0	0	1	0	1	3	1	0	1	0	0	0	0	0	0	7
Asian	2	3	0	0	2	5	3	4	2	3	4	0	2	2	0	32
Native Hawaiian or Other Pacific Islander	0	1	0	0	1	0	0	0	0	0	0	0	0	0	0	2
Black or African American	12	25	24	12	18	18	11	23	21	17	13	6	13	18	9	240
White	43	88	93	44	94	92	44	91	94	37	98	53	44	100	52	1067
More than one race	1	4	1	3	2	1	1	2	1	2	3	0	0	1	0	22
Unknown or Not Reported	3	0	2	1	1	1	0	0	0	1	0	0	1	0	0	10

Region of Enrollment
Region of Enrollment(participants)	3.75 µg H5N8 Plus AS03A Full Dose	7.5 µg H5N8 Plus AS03A Full Dose	15 µg H5N8 Plus AS03A Full Dose	3.75 µg H5N8 Plus AS03A Half Dose	7.5 µg H5N8 Plus AS03A Half Dose	15 µg H5N8 Plus AS03A Half Dose	3.75 µg H5N8 Plus MF59	7.5 µg H5N8 Plus MF59	15 µg H5N8 Plus MF59	3.75 µg H5N1 Plus AS03A Full Dose	7.5 µg H5N1 Plus AS03A Full Dose	15 µg H5N1 Plus AS03A Full Dose	3.75 µg H5N1 Plus MF59	7.5 µg H5N1 Plus MF59	15 µg H5N1 Plus MF59	Total
United States	61	121	121	60	119	120	60	120	119	60	118	59	60	121	61	1380

Study locations

20 sites

DelRicht Research - Atlanta
Atlanta, Georgia 30329, United States
Javara Research - Privia Medical Group Georgia
Savannah, Georgia 31406, United States
Accellacare - Duly Health and Care - Oak Lawn
Oak Lawn, Illinois 60453, United States
Johnson County Clin-Trials (JCCT)
Lenexa, Kansas 66219, United States
Alliance for Multispecialty Research - Wichita East - Heartland Research Associates
Wichita, Kansas 67207, United States
Alliance for Multispecialty Research - Lexington
Lexington, Kentucky 40509, United States
DelRicht Research - New Orleans - Prytania Street
New Orleans, Louisiana 70115, United States
DelRicht Research - Prairieville
Prairieville, Louisiana 70769, United States
Rochester Clinical Research
New York, New York 14609, United States
Accellacare - Cary
Cary, North Carolina 27518, United States
Accellacare of Hickory
Hickory, North Carolina 28601, United States
Accellacare - Piedmont Healthcare
Statesville, North Carolina 28625, United States
Accellacare - Tradd Court
Wilmington, North Carolina 28401, United States
CTI Clinical Research Center
Cincinnati, Ohio 45212, United States
DelRicht Research - Tulsa
Tulsa, Oklahoma 74133, United States
Tekton Research - Oklahoma - Primary Health Partners
Yukon, Oklahoma 73099, United States
Tekton Research - Austin
Austin, Texas 78745, United States
Javara Research - Privia Medical Group Gulf Coast
Conroe, Texas 77384, United States
Tekton Research - San Antonio
San Antonio, Texas 78229, United States
DelRicht Research - Virgina
Sterling, Virginia 20166, United States

References and documents

Study documents

Study protocol · Aug 5, 2024
Statistical analysis plan · Mar 27, 2025
Informed consent form · Aug 19, 2024

Documents are hosted by the registry — open the source record to download them.

Registry details

Key details

Study ID: NCT06560151
Lead sponsor: Biomedical Advanced Research and Development Authority
Collaborators: Rho Federal Systems Division, Inc., ICON plc
Responsible party: Sponsor
First posted: Aug 19, 2024
Start date: Aug 21, 2024
Primary completion: Jan 16, 2025
Completion: Jun 11, 2025
Results posted: Jul 23, 2026
Last update: Jul 23, 2026

Oversight

Data monitoring committee: Yes
FDA-regulated drug: Yes
FDA-regulated device: No

View the source record on ClinicalTrials.gov ↗

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