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Safety/Efficacy Study of Seqirus A/H7N9 IIV With or Without MF59(R) Adjuvant to Prevent Avian Influenza

A Phase II Study in Healthy Adults 18-64 Years Old to Assess the Safety, Reactogenicity and Immunogenicity of a Seqirus A/H7N9 Inactivated Influenza Vaccine Administered Intramuscularly With or Without MF59(R) Adjuvant

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03682120
Enrollment
372
Registered
2018-09-24
Start date
2018-11-02
Completion date
2020-04-30
Last updated
2021-05-17

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Avian Influenza, Influenza Immunisation

Keywords

A/H7N9, Healthy Adults, Immunogenicity, Influenza vaccine, MF59(R) adjuvant, Reactogenicity, Safety

Brief summary

This is a randomized, double-blinded, Phase II study in healthy males and non-pregnant females, 18-64 years of age. This clinical trial is designed to assess the safety, reactogenicity, and immunogenicity of a pre-pandemic 2017 monovalent inactivated influenza A/H7N9 virus vaccine (2017 H7N9 IIV) manufactured by Seqirus Inc (Seqirus) administered at different dosages (3.75 microgram mcg, 7.5 mcg and 15 mcg of hemagglutinin (HA) per dose) given with MF59(R) adjuvant manufactured by Seqirus Inc., or without adjuvant (15 mcg of HA per dose). Phosphate buffered saline (PBS) diluent manufactured by Patheon Manufacturing Services LLC will be used to achieve certain targeted doses. Approximately 371 subjects who are in good health and meet all eligibility criteria will be randomized into one of 4 study groups. The study will be conducted at up to 7 Vaccine and Treatment Unit (VTEU) sites and will last approximately 17 months, with subject participation duration of approximately 13 months. The Primary Objectives of the study are: 1) To assess the safety and reactogenicity following receipt of two doses of 2017 H7N9 IIV administered intramuscularly (IM) at different dosages approximately 21 days apart given with or without MF59(R) adjuvant; 2) To assess the serum hemagglutinin inhibition (HAI) and neutralizing (Neut) antibody responses approximately 21 days following receipt of two doses of 2017 H7N9 IIV administered IM at different dosages approximately 21 days apart with or without MF59(R) adjuvant.

Detailed description

This is a randomized, double-blinded, Phase II study in healthy males and non-pregnant females, 18-64 years of age. This clinical trial is designed to assess the safety, reactogenicity, and immunogenicity of a pre-pandemic 2017 monovalent inactivated influenza A/H7N9 virus vaccine (2017 H7N9 IIV) manufactured by Seqirus Inc (Seqirus) administered at different dosages (3.75 mcg, 7.5 mcg and 15 mcg of hemagglutinin (HA) per dose) given with MF59(R) adjuvant manufactured by Seqirus Inc., or without adjuvant (15 mcg of HA per dose). Phosphate buffered saline (PBS) diluent manufactured by Patheon Manufacturing Services LLC will be used to achieve certain targeted doses. Approximately 371 subjects who are in good health and meet all eligibility criteria will be randomized into one of 4 study groups. The study will be conducted at up to 7 Vaccine and Treatment Unit (VTEU) sites and will last approximately 17 months, with subject participation duration of approximately 13 months. The Primary Objectives of the study are: 1) To assess the safety and reactogenicity following receipt of two doses of 2017 H7N9 IIV administered intramuscularly (IM) at different dosages approximately 21 days apart given with or without MF59(R) adjuvant; 2) To assess the serum hemagglutinin inhibition (HAI) and Neutralizing (Neut) antibody responses approximately 21 days following receipt of two doses of 2017 H7N9 IIV administered IM at different dosages approximately 21 days apart with or without MF59(R) adjuvant. The secondary Objectives are: 1) To assess all unsolicited non-serious Adverse Events (AEs) following receipt of two doses of a 2017 H7N9 IIV administered IM at different dosages approximately 21 days apart with or without MF59(R) adjuvant; 2) To assess medically-attended adverse events (MAAEs) including new-onset chronic medical conditions (NOCMCs), potentially immune-mediated medical conditions (PIMMCs), and all Serious Adverse Events (SAEs) following receipt of two doses of a 2017 H7N9 IIV administered IM at different dosages approximately 21 days apart with or without MF59(R) adjuvant; 3) To assess the serum HAI and Neut antibody responses approximately 7 and 21 days following receipt of a single dose, and approximately 7 days following receipt of two doses of 2017 H7N9 IIV administered IM at different dosages approximately 21 days apart with or without MF59(R) adjuvant.

Interventions

BIOLOGICALA/H7N9

Monovalent inactivated, subunit influenza virus vaccine containing the HA and NA from influenza A/Hong Kong/125/2017 (H7N9) and the PB2, PB1, PA, NP, M and NS genes from A/Puerto Rico/8/1934 (H1N1).

DRUGMF59

Microfluoridized adjuvant 59 (MF59) is an oil-in-water emulsion.

Diluent for Influenza Virus Vaccine.

Sponsors

National Institute of Allergy and Infectious Diseases (NIAID)
Lead SponsorNIH

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender
ALL
Age
18 Years to 64 Years
Healthy volunteers
Yes

Inclusion criteria

1. Provide written informed consent prior to initiation of any study procedures. 2. Are able to understand and comply with planned study procedures and be available for all study visits. 3. Are males or non-pregnant females, 18-64 years of age, inclusive. 4. Are in good health\*. \*As determined by physical examination and medical history to evaluate acute or currently ongoing chronic medical diagnoses or conditions, defined as those that have been present for at least 90 days, which would affect the assessment of the safety of subjects or the immunogenicity of study vaccinations. Chronic medical diagnoses or conditions should be stable for the last 60 days (no hospitalizations, Emergency Room, or urgent care for condition and no adverse symptoms that need medical intervention such as medication change/supplemental oxygen). This includes no change in chronic prescription medication, dose, or frequency as a result of deterioration of the chronic medical diagnosis or condition in the 60 days prior to enrollment. Any prescription change that is due to change of health care provider, insurance company, etc., or that is done for financial reasons, as long as in the same class of medication, will not be considered a deviation of this inclusion criterion. Any change in prescription medication due to improvement of a disease outcome, as determined by the site principal investigator or appropriate sub-investigator, will not be considered a deviation of this inclusion criterion. Subjects may be on chronic or as needed (prn) medications if, in the opinion of the site principal investigator or appropriate sub-investigator, they pose no additional risk to subject safety or assessment of reactogenicity and immunogenicity and do not indicate a worsening of medical diagnosis or condition. Similarly, medication changes subsequent to enrollment and study vaccination are acceptable provided there was no deterioration in the subject's chronic medical condition that necessitated a medication change, and there is no additional risk to the subject or interference with the evaluation of responses to study vaccination. \[Topical, nasal, and inhaled medications (with the exception of inhaled corticosteroids), herbals, vitamins, and supplements are permitted\]. 5. Oral temperature is less than 100.0 degree Fahrenheit. 6. Pulse is 47 to 100 beats per minute, inclusive. 7. Systolic blood pressure is 85 to 150 millimeters of Mercury, inclusive. 8. Diastolic blood pressure is 55 to 95 millimeters of Mercury, inclusive. 9. Women of childbearing potential\* must agree to practice an acceptable contraception method\*\* from 30 days before first study vaccination until 60 days after last study vaccination. \*Not sterilized via tubal ligation, bilateral oophorectomy, salpingectomy, hysterectomy, or successful Essure(R) placement (permanent, non-surgical, non-hormonal sterilization) with documented radiological confirmation test at least 90 days after the procedure, and still menstruating or \< 1 year of the last menses if menopausal. \*\*Includes non-male sexual relationships, abstinence from sexual intercourse with a male partner, monogamous relationship with vasectomized partner who has been vasectomized for 180 days or more prior to the subject receiving the first study vaccination, barrier methods such as male or female condoms with spermicide or with the use of applied spermicide, intrauterine devices, NuvaRing(R), and licensed hormonal methods such as implants, injectables, or oral contraceptives (the pill). 10. Women of childbearing potential must have a negative serum or urine pregnancy test within 24 hours prior to study vaccination.

Exclusion criteria

1. Have an acute illness\*, as determined by the site Principal Investigatoor or appropriate sub-investigator, within 72 hours prior to study vaccination. \*An acute illness which is nearly resolved with only minor residual symptoms remaining is allowable if, in the opinion of the site principal investigator or appropriate sub-investigator, the residual symptoms will not interfere with the ability to assess safety parameters as required by the protocol. 2. Have any medical disease or condition that, in the opinion of the site Principal Investigator or appropriate sub-investigator, is a contraindication to study participation\*. \*Including acute or chronic medical disease or condition, defined as persisting for at least 90 days, that would place the subject at an unacceptable risk of injury, render the subject unable to meet the requirements of the protocol, or may interfere with the evaluation of responses or the subject's successful completion of this trial. 3. Have immunosuppression as a result of an underlying illness or treatment, a recent history or current use of immunosuppressive or immunomodulating disease therapy. 4. Use of anticancer chemotherapy or radiation therapy (cytotoxic) within 3 years prior to study vaccination. 5. Have known active neoplastic disease or a history of any hematologic malignancy. Non-melanoma, treated, skin cancers are permitted. 6. Have known human immunodeficiency virus (HIV), hepatitis B, or hepatitis C infection. 7. Have known hypersensitivity or allergy to eggs, egg or chicken protein, neomycin, kanamycin, formaldehyde, polysorbate 80, cetyltrimethylammonium bromide (CTAB), squalene-based adjuvants, or other components of the study vaccine. 8. Have a history of severe reactions following previous immunization with licensed or unlicensed influenza vaccines. 9. Have a history of Guillian-Barre Syndrome. 10. Have a history of convulsions or encephalomyelitis within 90 days prior to study vaccination. 11. Have a history of Potentially Immune Mediated Medical Conditions (PIMMCs) 12. Have a history of alcohol or drug abuse within 5 years prior to study vaccination. 13. Have any diagnosis, current or past, of schizophrenia, bipolar disease, or other psychiatric diagnosis that may interfere with subject compliance or safety evaluations. 14. Have been hospitalized for psychiatric illness, history of suicide attempt, or confinement for danger to self or others within 10 years prior to study vaccination. 15. Have taken oral or parenteral (including intra-articular) corticosteroids of any dose within 30 days prior to study vaccination. 16. Have taken high-dose inhaled corticosteroids\* within 30 days prior to each study vaccination. \*High-dose defined as per age as using inhaled high dose per reference chart https://www.nhlbi.nih.gov/files/docs/guidelines/asthma\_qrg.pdf. 17. Received a licensed live vaccine within 30 days prior to the first study vaccination, or plan to receive a licensed live vaccine within 30 days before or after each study vaccination. 18. Received or plan to receive a licensed, inactivated, vaccine (excluding all flu vaccines) within 14 days before or after each study vaccination. 19. Received or plan to receive seasonal inactivated influenza virus (IIV) within 21 days before or after each study vaccination. 20. Received immunoglobulin or other blood products (with exception of Rho D immunoglobulin) within 90 days prior to each study vaccination. 21. Received an experimental agent\* within 30 days prior to the first study vaccination, or expect to receive an experimental agent\*\* during the 13-month trial-reporting period. \*Including vaccine, drug, biologic, device, blood product, or medication. \*\*Other than from participation in this trial. 22. Are participating or plan to participate in another clinical trial with an interventional agent\* that will be received during the 13-month trial-reporting period. \*Including licensed or unlicensed vaccine, drug, biologic, device, blood product, or medication. 23. Received or plan to receive an influenza A / H7 vaccine\* or have a history of influenza A / H7 subtype infection. \*And assigned to a group receiving influenza A / H7 vaccine, does not apply to documented placebo recipients. 24. Have traveled to mainland China and had substantial\* direct contact with live or freshly slaughtered poultry or pigeons within the past five years. \*Substantial contact is defined as visited a poultry farm and/or a live poultry market. 25. Occupational exposure to or substantial direct physical contact\* with birds in the past year and through the 21 days after the second study vaccination. \*Exposure to free range chickens in the yard is exclusionary. Casual contact with birds at petting zoos or county or state fairs or having pet birds does not exclude subjects from study participation. 26. Female subjects who are breastfeeding at any given time from the first study vaccination until 30 days after the last study vaccination. 27. Plan to travel outside the US (continental US, Hawaii, and Alaska) from enrollment through 21 days after the second study vaccination. 28. Receipt of Multimeric-001 (M-001) vaccine.

Design outcomes

Primary

MeasureTime frameDescription
Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) AntibodiesDay 43Blood was collected for the Neutralizing assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. Seroconversion was defined as Neut pre-vaccination titer \<1:10 and post-vaccination titer \>= 1:40 or pre-vaccination titer \>= 1:10 and minimum 4-fold rise in post-vaccination antibody titer. 21 days after second dose of H7N9 is Day 43.
Geometric Mean Titers (GMT) of Serum Hemagglutinin Inhibition (HAI) AntibodiesDay 43Blood was collected for HAI assay which was conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The geometric mean titer was calculated for each study arm from the available results at 21 days after the second dose of H7N9 (Day 43).
Geometric Mean Titers (GMT) of Serum Neutralizing (Neut) AntibodiesDay 43Blood was collected for Neutralizing assay which was conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The geometric mean titer was calculated for each study arm from the available results at 21 days after the second dose of H7N9 (Day 43).
Number of Participants With Clinical Safety Laboratory Adverse EventsDay 1 through Day 8Laboratory parameters include alanine aminotransferase (ALT), bilirubin, creatinine, hemoglobin, platelets and white blood cells (WBC). Thresholds for adverse events were considered as ALT 44 IU/L or greater (female) or 61 IU/L or greater (male); bilirubin 1.30 mg/dL or greater; creatinine 1.1 mg/dL or greater (female) or 1.4 mg/dL or greater (male); hemoglobin 11.4 g/dL or lower (female) or 12.4 g/dL or lower (male); platelets 139 x10\^3/µL or below or 416 x10\^3/µL or greater; or WBC or 3.9 x10\^3/µL or lower or 10.6 x10\^3/µL or higher.
Number of Participants With Solicited Injection Site Reactogenicity EventsDay 1 through Day 8Injection site AEs solicited on a memory aid provided to participants included Pain, Tenderness, Itching/Pruritus, Ecchymosis/Bruising (functional grade based on interference with daily activities), Ecchymosis/Bruising (any measured value \>0mm), Erythema/Redness (functional grade), Erythema/ Redness (any measured value \>0mm), Induration/Swelling (functional grade), and Induration/Swelling (any measured value \>0mm). Participants are considered reporting the injection site AE if they reported mild or greater severity at any time during the 8 days at or following the first vaccination.
Number of Participants With Study Vaccine-related Serious Adverse Events (SAEs)Day 1 through Day 387SAEs included any untoward medical occurrence that resulted in death; was life threatening; was a persistent/significant disability/incapacity; required inpatient hospitalization or prolongation or a congenital anomaly/birth defect. Events are included if deemed by the investigator to be related to the study product.
Number of Participants With Systemic Reactogenicity EventsDay 1 through Day 8Systemic AEs solicited on a memory aid provided to participants included Elevated Oral Temperature, Feverishness, Fatigue, Malaise, Myalgia, Arthralgia, Headache, and Nausea. Participants are considered reporting the systemic AE if they reported mild or greater severity at any time during the 8 days at or following the first vaccination.
Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or GreaterDay 43Blood was collected for the HAI assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The percentage of participants with HAI titer \>= 1:40 was calculated for each study group from the available results at 21 days after second dose of H7N9 (Day 43).
Percentage of Participants Achieving Neutralizing (Neut) Antibody Titers of 1:40 or GreaterDay 43Blood was collected for the Neutralizing assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The percentage of participants with Neut titer \>= 1:40 was calculated for each study group from the available results at 21 days after second dose of H7N9 (Day 43).
Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) AntibodiesDay 43Blood was collected for the HAI assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. Seroconversion was defined as HAI pre-vaccination titer \<1:10 and post-vaccination titer \>= 1:40 or pre-vaccination titer \>= 1:10 and minimum 4-fold rise in post-vaccination antibody titer. 21 days after second dose of H7N9 is Day 43.

Secondary

MeasureTime frameDescription
Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) AntibodiesDay 1Blood was collected for HAI assay which was conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The geometric mean titer was calculated for each study arm from the available results at baseline (Day 1).
Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) AntibodiesDay 1Blood was collected for Neutralizing assay which was conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The geometric mean titer was calculated for each study arm from the available results at baseline (Day 1).
Number of Participants With Serious Adverse Events (SAEs), Regardless of the Assessment of RelatednessDay 1 through Day 387SAEs included any untoward medical occurrence that resulted in death; was life threatening; was a persistent/significant disability/incapacity; required inpatient hospitalization or prolongation or a congenital anomaly/birth defect. All events are included regardless of relationship to the study product.
Number of Participants With Unsolicited Adverse Events, Regardless of the Assessment of Seriousness or RelatednessDay 1 through Day 22Adverse events were defined as any untoward medical occurrence in a participant administered a pharmaceutical product regardless of its causal relationship to the study treatment. Non-serious AEs were collected from participants at follow up visits through 21 days after each vaccination. Adverse events were MedDRA coded and are summarized by MedDRA System Organ Class (SOC).
Number of Participants With Medically-Attended Adverse Events (MAAEs), New-Onset Chronic Medical Conditions (NOCMCs), and Potentially Immune-Mediated Medical Conditions (PIMMCs)Day 1 through Day 387Participants were queried at each visit for the occurrence of medically-attended adverse events (MAAEs), including new-onset chronic medical conditions (NOCMCs) and potentially immune-mediated medical conditions (PIMMCs) throughout the duration of the study.
Number of Participants With Study Vaccine-related Unsolicited Non-serious Adverse Events (AEs)Day 1 through Day 22Adverse events were defined as any untoward medical occurrence in a participant administered a pharmaceutical product regardless of its causal relationship to the study treatment. Non-serious AEs were collected from participants at follow up visits through 21 days after each vaccination. The site investigator determined vaccine related as a reasonable possibility that the study product caused the AE. Reasonable possibility means that there is evidence to suggest a causal relationship between the study product and the AE. Adverse events were MedDRA coded and are summarized by MedDRA System Organ Class (SOC).
Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or GreaterDay 1Blood was collected for the HAI assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The percentage of participants with HAI titer \>= 1:40 was calculated for each study group from the available results at baseline (Day 1).
Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or GreaterDay 1Blood was collected for the Neutralizing assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The percentage of subjects with Neut titer \>= 1:40 was calculated for each study group from the available results at baseline (Day 1).
Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) AntibodiesDay 8Blood was collected for the HAI assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. Seroconversion was defined as HAI pre-vaccination titer \<1:10 and post-vaccination titer \>= 1:40 or pre-vaccination titer \>= 1:10 and minimum 4-fold rise in post-vaccination antibody titer. Day 8 is 7 days after the first dose of H7N9.
Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) AntibodiesDay 8Blood was collected for the Neutralizing assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. Seroconversion was defined as Neut pre-vaccination titer \<1:10 and post-vaccination titer \>= 1:40 or pre-vaccination titer \>= 1:10 and minimum 4-fold rise in post-vaccination antibody titer. Day 8 is 7 days after the first dose of H7N9.

Countries

United States

Participant flow

Recruitment details

Participants were healthy males and non-pregnant females between 18 and 64 years old, inclusively. They were recruited from the communities at large around the clinical sites. Participants were enrolled between 27NOV2018 and 02APR2019.

Participants by arm

ArmCount
3.75 mcg A/H7N9+MF59
3.75 mcg per 0.5 ml dose of 2017 A/H7N9 Inactivated Influenza Virus Vaccine (IIV) + MF59(R) adjuvant administered intramuscularly on Day 1 and Day 22. Phosphate buffered saline (PBS) diluent may be used to achieve targeted dosages.
105
7.5 mcg A/H7N9+MF59
7.5 mcg per 0.5 ml dose of 2017 A/H7N9 Inactivated Influenza Virus Vaccine (IIV) + MF59(R) adjuvant administered intramuscularly on Day 1 and Day 22. Phosphate buffered saline (PBS) diluent may be used to achieve targeted dosages.
105
15 mcg A/H7N9+MF59
15 mcg per 0.5 ml dose of 2017 A/H7N9 Inactivated Influenza Virus Vaccine (IIV) + MF59(R) adjuvant administered intramuscularly on Day 1 and Day 22. Phosphate buffered saline (PBS) diluent may be used to achieve targeted dosages.
105
15 mcg A/H7N9
15 mcg per 0.5 ml dose of 2017 A/H7N9 Inactivated Influenza Virus Vaccine (IIV) unadjuvanted administered intramuscularly on Day 1 and Day 22. Phosphate buffered saline (PBS) diluent may be used to achieve targeted dosages.
57
Total372

Withdrawals & dropouts

PeriodReasonFG000FG001FG002FG003
Overall StudyDeath0100
Overall StudyEnrolled but Treatment Not Administered0100
Overall StudyLost to Follow-up11452
Overall StudyPhysician Decision1000
Overall StudyWithdrawal by Subject1230

Baseline characteristics

Characteristic3.75 mcg A/H7N9+MF597.5 mcg A/H7N9+MF5915 mcg A/H7N9+MF5915 mcg A/H7N9Total
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
0 Participants0 Participants0 Participants0 Participants0 Participants
Age, Categorical
Between 18 and 65 years
105 Participants105 Participants105 Participants57 Participants372 Participants
Age, Continuous39.1 years
STANDARD_DEVIATION 13.6
40.5 years
STANDARD_DEVIATION 13.7
38.8 years
STANDARD_DEVIATION 13.3
43.8 years
STANDARD_DEVIATION 15.1
40.2 years
STANDARD_DEVIATION 13.8
Ethnicity (NIH/OMB)
Hispanic or Latino
7 Participants6 Participants10 Participants3 Participants26 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
98 Participants99 Participants95 Participants54 Participants346 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants0 Participants0 Participants
Prior Seasonal Influenza Vaccination (2017-2018 or 2018-2019)
2017-2018 Only
10 Participants8 Participants8 Participants4 Participants30 Participants
Prior Seasonal Influenza Vaccination (2017-2018 or 2018-2019)
2018-2019 Only
17 Participants14 Participants14 Participants6 Participants51 Participants
Prior Seasonal Influenza Vaccination (2017-2018 or 2018-2019)
Both 2017-2018 and 2018-2019
61 Participants65 Participants60 Participants33 Participants219 Participants
Prior Seasonal Influenza Vaccination (2017-2018 or 2018-2019)
Neither
17 Participants18 Participants23 Participants14 Participants72 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
7 Participants6 Participants3 Participants4 Participants20 Participants
Race (NIH/OMB)
Black or African American
17 Participants12 Participants16 Participants13 Participants58 Participants
Race (NIH/OMB)
More than one race
2 Participants4 Participants2 Participants2 Participants10 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
1 Participants2 Participants2 Participants1 Participants6 Participants
Race (NIH/OMB)
White
78 Participants81 Participants82 Participants37 Participants278 Participants
Region of Enrollment
United States
105 participants105 participants105 participants57 participants372 participants
Sex: Female, Male
Female
59 Participants63 Participants65 Participants29 Participants216 Participants
Sex: Female, Male
Male
46 Participants42 Participants40 Participants28 Participants156 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
EG003
affected / at risk
deaths
Total, all-cause mortality
0 / 1051 / 1050 / 1040 / 57
other
Total, other adverse events
93 / 10595 / 10592 / 10445 / 57
serious
Total, serious adverse events
1 / 1056 / 1054 / 1041 / 57

Outcome results

Primary

Geometric Mean Titers (GMT) of Serum Hemagglutinin Inhibition (HAI) Antibodies

Blood was collected for HAI assay which was conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The geometric mean titer was calculated for each study arm from the available results at 21 days after the second dose of H7N9 (Day 43).

Time frame: Day 43

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for HAI antibody assays for which valid results were reported.

ArmMeasureValue (GEOMETRIC_MEAN)
3.75 mcg A/H7N9+MF59Geometric Mean Titers (GMT) of Serum Hemagglutinin Inhibition (HAI) Antibodies23.3 titer
7.5 mcg A/H7N9+MF59Geometric Mean Titers (GMT) of Serum Hemagglutinin Inhibition (HAI) Antibodies19.9 titer
15 mcg A/H7N9+MF59Geometric Mean Titers (GMT) of Serum Hemagglutinin Inhibition (HAI) Antibodies24.2 titer
15 mcg A/H7N9Geometric Mean Titers (GMT) of Serum Hemagglutinin Inhibition (HAI) Antibodies6.0 titer
Primary

Geometric Mean Titers (GMT) of Serum Neutralizing (Neut) Antibodies

Blood was collected for Neutralizing assay which was conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The geometric mean titer was calculated for each study arm from the available results at 21 days after the second dose of H7N9 (Day 43).

Time frame: Day 43

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for Neut antibody assays for which valid results were reported.

ArmMeasureValue (GEOMETRIC_MEAN)
3.75 mcg A/H7N9+MF59Geometric Mean Titers (GMT) of Serum Neutralizing (Neut) Antibodies24.9 titer
7.5 mcg A/H7N9+MF59Geometric Mean Titers (GMT) of Serum Neutralizing (Neut) Antibodies24.1 titer
15 mcg A/H7N9+MF59Geometric Mean Titers (GMT) of Serum Neutralizing (Neut) Antibodies28.0 titer
15 mcg A/H7N9Geometric Mean Titers (GMT) of Serum Neutralizing (Neut) Antibodies6.4 titer
Primary

Number of Participants With Clinical Safety Laboratory Adverse Events

Laboratory parameters include alanine aminotransferase (ALT), bilirubin, creatinine, hemoglobin, platelets and white blood cells (WBC). Thresholds for adverse events were considered as ALT 44 IU/L or greater (female) or 61 IU/L or greater (male); bilirubin 1.30 mg/dL or greater; creatinine 1.1 mg/dL or greater (female) or 1.4 mg/dL or greater (male); hemoglobin 11.4 g/dL or lower (female) or 12.4 g/dL or lower (male); platelets 139 x10\^3/µL or below or 416 x10\^3/µL or greater; or WBC or 3.9 x10\^3/µL or lower or 10.6 x10\^3/µL or higher.

Time frame: Day 1 through Day 8

Population: The Safety Analysis population includes all participants who received at least one dose of study vaccine. Participants with at least one lab result reported for Day 8 were included for this outcome measure.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
3.75 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsWBC9 Participants
3.75 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsHemoglobin4 Participants
3.75 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsPlatelets2 Participants
3.75 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsALT3 Participants
3.75 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsTotal Bilirubin0 Participants
3.75 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsCreatinine4 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsCreatinine0 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsALT1 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsWBC8 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsPlatelets3 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsHemoglobin5 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsTotal Bilirubin1 Participants
15 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsHemoglobin2 Participants
15 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsPlatelets5 Participants
15 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsALT1 Participants
15 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsCreatinine1 Participants
15 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsTotal Bilirubin1 Participants
15 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsWBC5 Participants
15 mcg A/H7N9Number of Participants With Clinical Safety Laboratory Adverse EventsTotal Bilirubin1 Participants
15 mcg A/H7N9Number of Participants With Clinical Safety Laboratory Adverse EventsCreatinine1 Participants
15 mcg A/H7N9Number of Participants With Clinical Safety Laboratory Adverse EventsHemoglobin4 Participants
15 mcg A/H7N9Number of Participants With Clinical Safety Laboratory Adverse EventsALT0 Participants
15 mcg A/H7N9Number of Participants With Clinical Safety Laboratory Adverse EventsWBC2 Participants
15 mcg A/H7N9Number of Participants With Clinical Safety Laboratory Adverse EventsPlatelets0 Participants
Primary

Number of Participants With Clinical Safety Laboratory Adverse Events

Laboratory parameters include alanine aminotransferase (ALT), bilirubin, creatinine, hemoglobin, platelets and white blood cells (WBC). Thresholds for adverse events were considered as ALT 44 IU/L or greater (female) or 61 IU/L or greater (male); bilirubin 1.30 mg/dL or greater; creatinine 1.1 mg/dL or greater (female) or 1.4 mg/dL or greater (male); hemoglobin 11.4 g/dL or lower (female) or 12.4 g/dL or lower (male); platelets 139 x10\^3/µL or below or 416 x10\^3/µL or greater; or WBC or 3.9 x10\^3/µL or lower or 10.6 x10\^3/µL or higher.

Time frame: Day 22 to Day 29

Population: The Safety Analysis population includes all participants who received at least one dose of study vaccine. Participants with at least one lab result reported for Day 29 were included for this outcome measure.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
3.75 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsCreatinine1 Participants
3.75 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsWBC11 Participants
3.75 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsHemoglobin3 Participants
3.75 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsPlatelets3 Participants
3.75 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsTotal Bilirubin1 Participants
3.75 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsALT2 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsTotal Bilirubin1 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsCreatinine1 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsHemoglobin6 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsWBC13 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsPlatelets6 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsALT2 Participants
15 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsWBC9 Participants
15 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsTotal Bilirubin1 Participants
15 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsALT1 Participants
15 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsHemoglobin2 Participants
15 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsCreatinine1 Participants
15 mcg A/H7N9+MF59Number of Participants With Clinical Safety Laboratory Adverse EventsPlatelets0 Participants
15 mcg A/H7N9Number of Participants With Clinical Safety Laboratory Adverse EventsCreatinine0 Participants
15 mcg A/H7N9Number of Participants With Clinical Safety Laboratory Adverse EventsWBC4 Participants
15 mcg A/H7N9Number of Participants With Clinical Safety Laboratory Adverse EventsHemoglobin1 Participants
15 mcg A/H7N9Number of Participants With Clinical Safety Laboratory Adverse EventsPlatelets0 Participants
15 mcg A/H7N9Number of Participants With Clinical Safety Laboratory Adverse EventsALT0 Participants
15 mcg A/H7N9Number of Participants With Clinical Safety Laboratory Adverse EventsTotal Bilirubin2 Participants
Primary

Number of Participants With Solicited Injection Site Reactogenicity Events

Injection site AEs solicited on a memory aid provided to participants included Pain, Tenderness, Itching/Pruritus, Ecchymosis/Bruising (functional grade based on interference with daily activities), Ecchymosis/Bruising (any measured value \>0mm), Erythema/Redness (functional grade), Erythema/ Redness (any measured value \>0mm), Induration/Swelling (functional grade), and Induration/Swelling (any measured value \>0mm). Participants are considered reporting the injection site AE if they reported mild or greater severity at any time during the 8 days at or following the second vaccination.

Time frame: Day 22 through Day 29

Population: The Safety Analysis population includes all participants who received at least one dose of study vaccine. Participants who received the second dose of study vaccine were included for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
3.75 mcg A/H7N9+MF59Number of Participants With Solicited Injection Site Reactogenicity Events63 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Solicited Injection Site Reactogenicity Events55 Participants
15 mcg A/H7N9+MF59Number of Participants With Solicited Injection Site Reactogenicity Events57 Participants
15 mcg A/H7N9Number of Participants With Solicited Injection Site Reactogenicity Events13 Participants
Primary

Number of Participants With Solicited Injection Site Reactogenicity Events

Injection site AEs solicited on a memory aid provided to participants included Pain, Tenderness, Itching/Pruritus, Ecchymosis/Bruising (functional grade based on interference with daily activities), Ecchymosis/Bruising (any measured value \>0mm), Erythema/Redness (functional grade), Erythema/ Redness (any measured value \>0mm), Induration/Swelling (functional grade), and Induration/Swelling (any measured value \>0mm). Participants are considered reporting the injection site AE if they reported mild or greater severity at any time during the 8 days at or following the first vaccination.

Time frame: Day 1 through Day 8

Population: The Safety Analysis population includes all participants who received at least one dose of study vaccine. Participants who received the first dose of study vaccine were included for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
3.75 mcg A/H7N9+MF59Number of Participants With Solicited Injection Site Reactogenicity Events78 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Solicited Injection Site Reactogenicity Events76 Participants
15 mcg A/H7N9+MF59Number of Participants With Solicited Injection Site Reactogenicity Events70 Participants
15 mcg A/H7N9Number of Participants With Solicited Injection Site Reactogenicity Events20 Participants
Primary

Number of Participants With Study Vaccine-related Serious Adverse Events (SAEs)

SAEs included any untoward medical occurrence that resulted in death; was life threatening; was a persistent/significant disability/incapacity; required inpatient hospitalization or prolongation or a congenital anomaly/birth defect. Events are included if deemed by the investigator to be related to the study product.

Time frame: Day 1 through Day 387

Population: The Safety Analysis population includes all participants who received at least one dose of study vaccine.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
3.75 mcg A/H7N9+MF59Number of Participants With Study Vaccine-related Serious Adverse Events (SAEs)0 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Study Vaccine-related Serious Adverse Events (SAEs)0 Participants
15 mcg A/H7N9+MF59Number of Participants With Study Vaccine-related Serious Adverse Events (SAEs)0 Participants
15 mcg A/H7N9Number of Participants With Study Vaccine-related Serious Adverse Events (SAEs)0 Participants
Primary

Number of Participants With Systemic Reactogenicity Events

Systemic AEs solicited on a memory aid provided to participants included Elevated Oral Temperature, Feverishness, Fatigue, Malaise, Myalgia, Arthralgia, Headache, and Nausea. Participants are considered reporting the systemic AE if they reported mild or greater severity at any time during the 8 days at or following the second vaccination.

Time frame: Day 22 through Day 29

Population: The Safety Analysis population includes all participants who received at least one dose of study vaccine. Participants who received the second dose of study vaccine were included for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
3.75 mcg A/H7N9+MF59Number of Participants With Systemic Reactogenicity Events29 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Systemic Reactogenicity Events37 Participants
15 mcg A/H7N9+MF59Number of Participants With Systemic Reactogenicity Events27 Participants
15 mcg A/H7N9Number of Participants With Systemic Reactogenicity Events9 Participants
Primary

Number of Participants With Systemic Reactogenicity Events

Systemic AEs solicited on a memory aid provided to participants included Elevated Oral Temperature, Feverishness, Fatigue, Malaise, Myalgia, Arthralgia, Headache, and Nausea. Participants are considered reporting the systemic AE if they reported mild or greater severity at any time during the 8 days at or following the first vaccination.

Time frame: Day 1 through Day 8

Population: The Safety Analysis population includes all participants who received at least one dose of study vaccine. Participants who received the first dose of study vaccine were included for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
3.75 mcg A/H7N9+MF59Number of Participants With Systemic Reactogenicity Events50 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Systemic Reactogenicity Events43 Participants
15 mcg A/H7N9+MF59Number of Participants With Systemic Reactogenicity Events39 Participants
15 mcg A/H7N9Number of Participants With Systemic Reactogenicity Events23 Participants
Primary

Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater

Blood was collected for the HAI assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The percentage of participants with HAI titer \>= 1:40 was calculated for each study group from the available results at 21 days after second dose of H7N9 (Day 43).

Time frame: Day 43

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for HAI antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater43 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater30 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater40 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater0 percentage of participants
Primary

Percentage of Participants Achieving Neutralizing (Neut) Antibody Titers of 1:40 or Greater

Blood was collected for the Neutralizing assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The percentage of participants with Neut titer \>= 1:40 was calculated for each study group from the available results at 21 days after second dose of H7N9 (Day 43).

Time frame: Day 43

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for Neut antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Neutralizing (Neut) Antibody Titers of 1:40 or Greater45 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Neutralizing (Neut) Antibody Titers of 1:40 or Greater42 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Neutralizing (Neut) Antibody Titers of 1:40 or Greater44 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Neutralizing (Neut) Antibody Titers of 1:40 or Greater2 percentage of participants
Primary

Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies

Blood was collected for the HAI assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. Seroconversion was defined as HAI pre-vaccination titer \<1:10 and post-vaccination titer \>= 1:40 or pre-vaccination titer \>= 1:10 and minimum 4-fold rise in post-vaccination antibody titer. 21 days after second dose of H7N9 is Day 43.

Time frame: Day 43

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for HAI antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies43 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies30 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies40 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies0 percentage of participants
Primary

Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies

Blood was collected for the Neutralizing assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. Seroconversion was defined as Neut pre-vaccination titer \<1:10 and post-vaccination titer \>= 1:40 or pre-vaccination titer \>= 1:10 and minimum 4-fold rise in post-vaccination antibody titer. 21 days after second dose of H7N9 is Day 43.

Time frame: Day 43

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for Neut antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies45 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies42 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies44 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies2 percentage of participants
Secondary

Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies

Blood was collected for HAI assay which was conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The geometric mean titer was calculated for each study arm from the available results at baseline (Day 1).

Time frame: Day 1

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for HAI antibody assays for which valid results were reported.

ArmMeasureValue (GEOMETRIC_MEAN)
3.75 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies5.3 titer
7.5 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies5.3 titer
15 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies5.3 titer
15 mcg A/H7N9Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies5.3 titer
Secondary

Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies

Blood was collected for HAI assay which was conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The geometric mean titer was calculated for each study arm from the available results at 7 days post first vaccination (Day 8).

Time frame: Day 8

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for HAI antibody assays for which valid results were reported.

ArmMeasureValue (GEOMETRIC_MEAN)
3.75 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies5.4 titer
7.5 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies5.4 titer
15 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies6.0 titer
15 mcg A/H7N9Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies6.2 titer
Secondary

Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies

Blood was collected for HAI assay which was conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The geometric mean titer was calculated for each study arm from the available results at 21 days post first vaccination (Day 22).

Time frame: Day 22

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for HAI antibody assays for which valid results were reported.

ArmMeasureValue (GEOMETRIC_MEAN)
3.75 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies6.1 titer
7.5 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies5.8 titer
15 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies7.5 titer
15 mcg A/H7N9Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies6.1 titer
Secondary

Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies

Blood was collected for HAI assay which was conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The geometric mean titer was calculated for each study arm from the available results at 7 days post second vaccination (Day 29).

Time frame: Day 29

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for HAI antibody assays for which valid results were reported.

ArmMeasureValue (GEOMETRIC_MEAN)
3.75 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies17.4 titer
7.5 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies15.9 titer
15 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies23.6 titer
15 mcg A/H7N9Geometric Mean Titers (GMTs) of Serum Hemagglutination Inhibition (HAI) Antibodies6.5 titer
Secondary

Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies

Blood was collected for Neutralizing assay which was conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The geometric mean titer was calculated for each study arm from the available results at 7 days post second vaccination (Day 29).

Time frame: Day 29

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for Neut antibody assays for which valid results were reported.

ArmMeasureValue (GEOMETRIC_MEAN)
3.75 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies19.2 titer
7.5 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies18.9 titer
15 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies25.2 titer
15 mcg A/H7N9Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies6.3 titer
Secondary

Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies

Blood was collected for Neutralizing assay which was conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The geometric mean titer was calculated for each study arm from the available results at baseline (Day 1).

Time frame: Day 1

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for Neut antibody assays for which valid results were reported.

ArmMeasureValue (GEOMETRIC_MEAN)
3.75 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies5.0 titer
7.5 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies5.0 titer
15 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies5.1 titer
15 mcg A/H7N9Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies5.0 titer
Secondary

Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies

Blood was collected for Neutralizing assay which was conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The geometric mean titer was calculated for each study arm from the available results at 7 days post first vaccination (Day 8).

Time frame: Day 8

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for Neut antibody assays for which valid results were reported.

ArmMeasureValue (GEOMETRIC_MEAN)
3.75 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies5.2 titer
7.5 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies5.2 titer
15 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies5.5 titer
15 mcg A/H7N9Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies5.1 titer
Secondary

Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies

Blood was collected for Neutralizing assay which was conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The geometric mean titer was calculated for each study arm from the available results at 21 days post first vaccination (Day 22).

Time frame: Day 22

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for Neut antibody assays for which valid results were reported.

ArmMeasureValue (GEOMETRIC_MEAN)
3.75 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies6.3 titer
7.5 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies6.1 titer
15 mcg A/H7N9+MF59Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies7.0 titer
15 mcg A/H7N9Geometric Mean Titers (GMTs) of Serum Neutralizing (Neut) Antibodies5.2 titer
Secondary

Number of Participants With Medically-Attended Adverse Events (MAAEs), New-Onset Chronic Medical Conditions (NOCMCs), and Potentially Immune-Mediated Medical Conditions (PIMMCs)

Participants were queried at each visit for the occurrence of medically-attended adverse events (MAAEs), including new-onset chronic medical conditions (NOCMCs) and potentially immune-mediated medical conditions (PIMMCs) throughout the duration of the study.

Time frame: Day 1 through Day 387

Population: The Safety Analysis population includes all participants who received at least one dose of study vaccine.

ArmMeasureGroupValue (COUNT_OF_PARTICIPANTS)
3.75 mcg A/H7N9+MF59Number of Participants With Medically-Attended Adverse Events (MAAEs), New-Onset Chronic Medical Conditions (NOCMCs), and Potentially Immune-Mediated Medical Conditions (PIMMCs)Medically-attended adverse events23 Participants
3.75 mcg A/H7N9+MF59Number of Participants With Medically-Attended Adverse Events (MAAEs), New-Onset Chronic Medical Conditions (NOCMCs), and Potentially Immune-Mediated Medical Conditions (PIMMCs)Potentially immune-mediated medical condition0 Participants
3.75 mcg A/H7N9+MF59Number of Participants With Medically-Attended Adverse Events (MAAEs), New-Onset Chronic Medical Conditions (NOCMCs), and Potentially Immune-Mediated Medical Conditions (PIMMCs)New onset chronic medical condition6 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Medically-Attended Adverse Events (MAAEs), New-Onset Chronic Medical Conditions (NOCMCs), and Potentially Immune-Mediated Medical Conditions (PIMMCs)Medically-attended adverse events35 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Medically-Attended Adverse Events (MAAEs), New-Onset Chronic Medical Conditions (NOCMCs), and Potentially Immune-Mediated Medical Conditions (PIMMCs)Potentially immune-mediated medical condition0 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Medically-Attended Adverse Events (MAAEs), New-Onset Chronic Medical Conditions (NOCMCs), and Potentially Immune-Mediated Medical Conditions (PIMMCs)New onset chronic medical condition7 Participants
15 mcg A/H7N9+MF59Number of Participants With Medically-Attended Adverse Events (MAAEs), New-Onset Chronic Medical Conditions (NOCMCs), and Potentially Immune-Mediated Medical Conditions (PIMMCs)New onset chronic medical condition6 Participants
15 mcg A/H7N9+MF59Number of Participants With Medically-Attended Adverse Events (MAAEs), New-Onset Chronic Medical Conditions (NOCMCs), and Potentially Immune-Mediated Medical Conditions (PIMMCs)Medically-attended adverse events35 Participants
15 mcg A/H7N9+MF59Number of Participants With Medically-Attended Adverse Events (MAAEs), New-Onset Chronic Medical Conditions (NOCMCs), and Potentially Immune-Mediated Medical Conditions (PIMMCs)Potentially immune-mediated medical condition1 Participants
15 mcg A/H7N9Number of Participants With Medically-Attended Adverse Events (MAAEs), New-Onset Chronic Medical Conditions (NOCMCs), and Potentially Immune-Mediated Medical Conditions (PIMMCs)Medically-attended adverse events18 Participants
15 mcg A/H7N9Number of Participants With Medically-Attended Adverse Events (MAAEs), New-Onset Chronic Medical Conditions (NOCMCs), and Potentially Immune-Mediated Medical Conditions (PIMMCs)Potentially immune-mediated medical condition0 Participants
15 mcg A/H7N9Number of Participants With Medically-Attended Adverse Events (MAAEs), New-Onset Chronic Medical Conditions (NOCMCs), and Potentially Immune-Mediated Medical Conditions (PIMMCs)New onset chronic medical condition2 Participants
Secondary

Number of Participants With Serious Adverse Events (SAEs), Regardless of the Assessment of Relatedness

SAEs included any untoward medical occurrence that resulted in death; was life threatening; was a persistent/significant disability/incapacity; required inpatient hospitalization or prolongation or a congenital anomaly/birth defect. All events are included regardless of relationship to the study product.

Time frame: Day 1 through Day 387

Population: The Safety Analysis population includes all participants who received at least one dose of study vaccine.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
3.75 mcg A/H7N9+MF59Number of Participants With Serious Adverse Events (SAEs), Regardless of the Assessment of Relatedness1 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Serious Adverse Events (SAEs), Regardless of the Assessment of Relatedness6 Participants
15 mcg A/H7N9+MF59Number of Participants With Serious Adverse Events (SAEs), Regardless of the Assessment of Relatedness4 Participants
15 mcg A/H7N9Number of Participants With Serious Adverse Events (SAEs), Regardless of the Assessment of Relatedness1 Participants
Secondary

Number of Participants With Study Vaccine-related Unsolicited Non-serious Adverse Events (AEs)

Adverse events were defined as any untoward medical occurrence in a participant administered a pharmaceutical product regardless of its causal relationship to the study treatment. Non-serious AEs were collected from participants at follow up visits through 21 days after each vaccination. The site investigator determined vaccine related as a reasonable possibility that the study product caused the AE. Reasonable possibility means that there is evidence to suggest a causal relationship between the study product and the AE. Adverse events were MedDRA coded and are summarized by MedDRA System Organ Class (SOC).

Time frame: Day 22 through Day 43

Population: The Safety Analysis population includes all participants who received at least one dose of study vaccine. Participants who received Vaccination 2 were included for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
3.75 mcg A/H7N9+MF59Number of Participants With Study Vaccine-related Unsolicited Non-serious Adverse Events (AEs)5 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Study Vaccine-related Unsolicited Non-serious Adverse Events (AEs)4 Participants
15 mcg A/H7N9+MF59Number of Participants With Study Vaccine-related Unsolicited Non-serious Adverse Events (AEs)5 Participants
15 mcg A/H7N9Number of Participants With Study Vaccine-related Unsolicited Non-serious Adverse Events (AEs)3 Participants
Secondary

Number of Participants With Study Vaccine-related Unsolicited Non-serious Adverse Events (AEs)

Adverse events were defined as any untoward medical occurrence in a participant administered a pharmaceutical product regardless of its causal relationship to the study treatment. Non-serious AEs were collected from participants at follow up visits through 21 days after each vaccination. The site investigator determined vaccine related as a reasonable possibility that the study product caused the AE. Reasonable possibility means that there is evidence to suggest a causal relationship between the study product and the AE. Adverse events were MedDRA coded and are summarized by MedDRA System Organ Class (SOC).

Time frame: Day 1 through Day 22

Population: The Safety Analysis population includes all participants who received at least one dose of study vaccine. Participants who received Vaccination 1 were included for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
3.75 mcg A/H7N9+MF59Number of Participants With Study Vaccine-related Unsolicited Non-serious Adverse Events (AEs)9 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Study Vaccine-related Unsolicited Non-serious Adverse Events (AEs)5 Participants
15 mcg A/H7N9+MF59Number of Participants With Study Vaccine-related Unsolicited Non-serious Adverse Events (AEs)5 Participants
15 mcg A/H7N9Number of Participants With Study Vaccine-related Unsolicited Non-serious Adverse Events (AEs)2 Participants
Secondary

Number of Participants With Unsolicited Adverse Events, Regardless of the Assessment of Seriousness or Relatedness

Adverse events were defined as any untoward medical occurrence in a participant administered a pharmaceutical product regardless of its causal relationship to the study treatment. Non-serious AEs were collected from participants at follow up visits through 21 days after each vaccination. Adverse events were MedDRA coded and are summarized by MedDRA System Organ Class (SOC).

Time frame: Day 1 through Day 22

Population: The Safety Analysis population includes all participants who received at least one dose of study vaccine. Participants who received Vaccination 1 were included for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
3.75 mcg A/H7N9+MF59Number of Participants With Unsolicited Adverse Events, Regardless of the Assessment of Seriousness or Relatedness23 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Unsolicited Adverse Events, Regardless of the Assessment of Seriousness or Relatedness22 Participants
15 mcg A/H7N9+MF59Number of Participants With Unsolicited Adverse Events, Regardless of the Assessment of Seriousness or Relatedness27 Participants
15 mcg A/H7N9Number of Participants With Unsolicited Adverse Events, Regardless of the Assessment of Seriousness or Relatedness14 Participants
Secondary

Number of Participants With Unsolicited Adverse Events, Regardless of the Assessment of Seriousness or Relatedness

Adverse events were defined as any untoward medical occurrence in a participant administered a pharmaceutical product regardless of its causal relationship to the study treatment. Non-serious AEs were collected from participants at follow up visits through 21 days after each vaccination. Adverse events were MedDRA coded and are summarized by MedDRA System Organ Class (SOC).

Time frame: Day 22 through Day 43

Population: The Safety Analysis population includes all participants who received at least one dose of study vaccine. Participants who received Vaccination 2 were included for this outcome measure.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
3.75 mcg A/H7N9+MF59Number of Participants With Unsolicited Adverse Events, Regardless of the Assessment of Seriousness or Relatedness19 Participants
7.5 mcg A/H7N9+MF59Number of Participants With Unsolicited Adverse Events, Regardless of the Assessment of Seriousness or Relatedness18 Participants
15 mcg A/H7N9+MF59Number of Participants With Unsolicited Adverse Events, Regardless of the Assessment of Seriousness or Relatedness18 Participants
15 mcg A/H7N9Number of Participants With Unsolicited Adverse Events, Regardless of the Assessment of Seriousness or Relatedness14 Participants
Secondary

Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater

Blood was collected for the HAI assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The percentage of participants with HAI titer \>= 1:40 was calculated for each study group from the available results at 7 days post second vaccination (Day 29).

Time frame: Day 29

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for HAI antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater34 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater26 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater40 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater2 percentage of participants
Secondary

Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater

Blood was collected for the HAI assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The percentage of participants with HAI titer \>= 1:40 was calculated for each study group from the available results at baseline (Day 1).

Time frame: Day 1

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for HAI antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater0 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater0 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater0 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater0 percentage of participants
Secondary

Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater

Blood was collected for the HAI assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The percentage of participants with HAI titer \>= 1:40 was calculated for each study group from the available results at 7 days post first vaccination (Day 8).

Time frame: Day 8

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for HAI antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater0 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater0 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater2 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater4 percentage of participants
Secondary

Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater

Blood was collected for the HAI assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The percentage of participants with HAI titer \>= 1:40 was calculated for each study group from the available results at 21 days post first vaccination (Day 22).

Time frame: Day 22

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for HAI antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater4 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater0 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater6 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Hemagglutination Inhibition (HAI) Antibody Titer of 1:40 or Greater4 percentage of participants
Secondary

Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater

Blood was collected for the Neutralizing assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The percentage of subjects with Neut titer \>= 1:40 was calculated for each study group from the available results at baseline (Day 1).

Time frame: Day 1

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for Neut antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater0 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater0 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater0 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater0 percentage of participants
Secondary

Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater

Blood was collected for the Neutralizing assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The percentage of subjects with Neut titer \>= 1:40 was calculated for each study group from the available results at 7 days post first vaccination (Day 8).

Time frame: Day 8

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for Neut antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater0 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater0 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater0 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater0 percentage of participants
Secondary

Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater

Blood was collected for the Neutralizing assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The percentage of participants with Neut titer \>= 1:40 was calculated for each study group from the available results at 21 days post first vaccination (Day 22).

Time frame: Day 22

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for Neut antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater1 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater0 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater2 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater0 percentage of participants
Secondary

Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater

Blood was collected for the Neutralizing assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The percentage of participants with Neut titer \>= 1:40 was calculated for each study group from the available results at 7 days post second vaccination (Day 29).

Time frame: Day 29

Population: Blood was collected for the Neutralizing assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. The percentage of participants with Neut titer \>= 1:40 was calculated for each study group from the available results at 7 days post second vaccination (Day 29).

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater33 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater29 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater42 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Neutralizing (Neut) Antibody Titer of 1:40 or Greater0 percentage of participants
Secondary

Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies

Blood was collected for the HAI assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. Seroconversion was defined as HAI pre-vaccination titer \<1:10 and post-vaccination titer \>= 1:40 or pre-vaccination titer \>= 1:10 and minimum 4-fold rise in post-vaccination antibody titer. Day 8 is 7 days after the first dose of H7N9.

Time frame: Day 8

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for HAI antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies0 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies0 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies2 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies4 percentage of participants
Secondary

Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies

Blood was collected for the HAI assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. Seroconversion was defined as HAI pre-vaccination titer \<1:10 and post-vaccination titer \>= 1:40 or pre-vaccination titer \>= 1:10 and minimum 4-fold rise in post-vaccination antibody titer. Day 22 is 21 days after the first dose of H7N9.

Time frame: Day 22

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for HAI antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies4 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies0 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies6 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies4 percentage of participants
Secondary

Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies

Blood was collected for the HAI assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. Seroconversion was defined as HAI pre-vaccination titer \<1:10 and post-vaccination titer \>= 1:40 or pre-vaccination titer \>= 1:10 and mininmum 4-fold rise in post-vaccination antibody titer. Day 29 is 7 days after the second dose of H7N9.

Time frame: Day 29

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for HAI antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies34 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies26 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies40 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Seroconversion Defined by Hemagglutination Inhibition (HAI) Antibodies2 percentage of participants
Secondary

Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies

Blood was collected for the Neutralizing assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. Seroconversion was defined as Neut pre-vaccination titer \<1:10 and post-vaccination titer \>= 1:40 or pre-vaccination titer \>= 1:10 and minimum 4-fold rise in post-vaccination antibody titer. Day 8 is 7 days after the first dose of H7N9.

Time frame: Day 8

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for Neut antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies0 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies0 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies0 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies0 percentage of participants
Secondary

Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies

Blood was collected for the Neutralizing assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. Seroconversion was defined as Neut pre-vaccination titer \<1:10 and post-vaccination titer \>= 1:40 or pre-vaccination titer \>= 1:10 and minimum 4-fold rise in post-vaccination antibody titer. Day 22 is 21 days after the first dose of H7N9.

Time frame: Day 22

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for Neut antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies1 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies0 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies2 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies0 percentage of participants
Secondary

Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies

Blood was collected for the Neutralizing assay conducted with the 2017 H7N9 vaccine virus as the antigen. Each sample was tested at least twice per the laboratory's standard operating procedure, and the geometric mean of the replicate results was calculated as that sample's result. Seroconversion was defined as Neut pre-vaccination titer \<1:10 and post-vaccination titer \>= 1:40 or pre-vaccination titer \>= 1:10 and minimum 4-fold rise in post-vaccination antibody titer. Day 29 is 7 days after the second dose of H7N9.

Time frame: Day 29

Population: The modified intent-to-treat (mITT) population includes all participants who received at least one study vaccination and contributed both pre- and at least one post-study vaccination venous blood samples for Neut antibody assays for which valid results were reported.

ArmMeasureValue (NUMBER)
3.75 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies33 percentage of participants
7.5 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies29 percentage of participants
15 mcg A/H7N9+MF59Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies42 percentage of participants
15 mcg A/H7N9Percentage of Participants Achieving Seroconversion Defined by Neutralizing (Neut) Antibodies0 percentage of participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026