Trial Outcomes & Findings for A Study to Evaluate Safety and Immunogenicity of One or Two Booster Vaccinations With H5N6 Influenza Vaccine in Adults Primed With H5N1 Influenza Vaccine or Unprimed (NCT NCT05422326)

NCT ID: NCT05422326

Last Updated: 2026-05-13

Results Overview

GMT pre-vaccination, 1 and 3 weeks post-vaccination 1, and 3 weeks post-vaccination 2 Note: The Overall Number of Participants Analyzed (N) represents the total number of participants in the per-protocol set (PPS); definitions are provided in the Statistical Analysis Plan (SAP). The Number Analyzed (n) at each timepoint corresponds to the number of participants with an available serum analysis result for the relevant strain at that timepoint. Instances where n\<N reflect missing serum samples or non-evaluable results. All participants included in the Overall Number of Participants Analyzed contributed data to the analysis at one or more timepoints.

Recruitment status

COMPLETED

Study phase

PHASE2

Target enrollment

260 participants

Primary outcome timeframe

Day 1, Day 8, Day 22, Day 43

Results posted on

2026-05-13

Participant Flow

Subjects were enrolled between 18 July 2022 and 2 September 2022.

All enrolled subjects have been assigned to one of the three treatment groups.

Participant milestones

Participant milestones
Measure
Group 1
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Group 3
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Overall Study
STARTED
81
78
101
Overall Study
COMPLETED
75
74
95
Overall Study
NOT COMPLETED
6
4
6

Reasons for withdrawal

Reasons for withdrawal
Measure
Group 1
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Group 3
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Overall Study
Adverse Event
1
0
0
Overall Study
Death
1
0
0
Overall Study
Lost to Follow-up
0
3
3
Overall Study
Protocol Violation
0
1
1
Overall Study
Withdrawal by Subject
4
0
1
Overall Study
Unable to obtain blood sample
0
0
1

Baseline Characteristics

One missing value in Group 3

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
Group 1
n=81 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=78 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Group 3
n=101 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Total
n=260 Participants
Total of all reporting groups
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
n=81 Participants
0 Participants
n=78 Participants
0 Participants
n=101 Participants
0 Participants
n=260 Participants
Age, Continuous
52.8 years
STANDARD_DEVIATION 10.59 • n=81 Participants
52.8 years
STANDARD_DEVIATION 10.67 • n=78 Participants
47.9 years
STANDARD_DEVIATION 13.17 • n=101 Participants
50.9 years
STANDARD_DEVIATION 11.88 • n=260 Participants
Age, Customized
Age Group · 18-49 years
25 Participants
n=81 Participants
25 Participants
n=78 Participants
51 Participants
n=101 Participants
101 Participants
n=260 Participants
Age, Customized
Age Group · ≥50 years
56 Participants
n=81 Participants
53 Participants
n=78 Participants
50 Participants
n=101 Participants
159 Participants
n=260 Participants
Sex: Female, Male
Female
52 Participants
n=81 Participants
46 Participants
n=78 Participants
55 Participants
n=101 Participants
153 Participants
n=260 Participants
Sex: Female, Male
Male
29 Participants
n=81 Participants
32 Participants
n=78 Participants
46 Participants
n=101 Participants
107 Participants
n=260 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
13 Participants
n=81 Participants
17 Participants
n=78 Participants
23 Participants
n=101 Participants
53 Participants
n=260 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
67 Participants
n=81 Participants
60 Participants
n=78 Participants
78 Participants
n=101 Participants
205 Participants
n=260 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
1 Participants
n=81 Participants
1 Participants
n=78 Participants
0 Participants
n=101 Participants
2 Participants
n=260 Participants
Race (NIH/OMB)
Asian
1 Participants
n=81 Participants
2 Participants
n=78 Participants
2 Participants
n=101 Participants
5 Participants
n=260 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
n=81 Participants
0 Participants
n=78 Participants
0 Participants
n=101 Participants
0 Participants
n=260 Participants
Race (NIH/OMB)
Black or African American
6 Participants
n=81 Participants
13 Participants
n=78 Participants
18 Participants
n=101 Participants
37 Participants
n=260 Participants
Race (NIH/OMB)
White
74 Participants
n=81 Participants
61 Participants
n=78 Participants
80 Participants
n=101 Participants
215 Participants
n=260 Participants
Race (NIH/OMB)
More than one race
0 Participants
n=81 Participants
1 Participants
n=78 Participants
1 Participants
n=101 Participants
2 Participants
n=260 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
n=81 Participants
1 Participants
n=78 Participants
0 Participants
n=101 Participants
1 Participants
n=260 Participants
Region of Enrollment
United States
81 participants
n=81 Participants
78 participants
n=78 Participants
101 participants
n=101 Participants
260 participants
n=260 Participants
Influenza Vaccination Within Past 2 Years
Yes
54 Participants
n=81 Participants
47 Participants
n=78 Participants
65 Participants
n=101 Participants
166 Participants
n=260 Participants
Influenza Vaccination Within Past 2 Years
No
27 Participants
n=81 Participants
31 Participants
n=78 Participants
36 Participants
n=101 Participants
94 Participants
n=260 Participants
Height
167.92 cm
STANDARD_DEVIATION 8.613 • n=81 Participants
167.16 cm
STANDARD_DEVIATION 9.593 • n=78 Participants
168.71 cm
STANDARD_DEVIATION 11.246 • n=101 Participants
168.00 cm
STANDARD_DEVIATION 9.976 • n=260 Participants
Weight
81.59 kg
STANDARD_DEVIATION 16.193 • n=81 Participants • One missing value in Group 3
81.31 kg
STANDARD_DEVIATION 18.164 • n=78 Participants • One missing value in Group 3
85.39 kg
STANDARD_DEVIATION 23.164 • n=100 Participants • One missing value in Group 3
82.97 kg
STANDARD_DEVIATION 19.733 • n=259 Participants • One missing value in Group 3
Body Mass Index
28.95 kg/m2
STANDARD_DEVIATION 5.560 • n=81 Participants • One missing value in Group 3
29.01 kg/m2
STANDARD_DEVIATION 5.579 • n=78 Participants • One missing value in Group 3
29.96 kg/m2
STANDARD_DEVIATION 7.543 • n=100 Participants • One missing value in Group 3
29.36 kg/m2
STANDARD_DEVIATION 6.398 • n=259 Participants • One missing value in Group 3

PRIMARY outcome

Timeframe: Day 1, Day 8, Day 22, Day 43

Population: Per-protocol set defined as all subjects who correctly received the study vaccine, provided at least one evaluable serum sample at relevant timepoints, had no major protocol deviations leading to exclusion, and were not excluded due to other reasons prior to unblinding or analysis.

GMT pre-vaccination, 1 and 3 weeks post-vaccination 1, and 3 weeks post-vaccination 2 Note: The Overall Number of Participants Analyzed (N) represents the total number of participants in the per-protocol set (PPS); definitions are provided in the Statistical Analysis Plan (SAP). The Number Analyzed (n) at each timepoint corresponds to the number of participants with an available serum analysis result for the relevant strain at that timepoint. Instances where n\<N reflect missing serum samples or non-evaluable results. All participants included in the Overall Number of Participants Analyzed contributed data to the analysis at one or more timepoints.

Outcome measures

Outcome measures
Measure
Group 3
n=95 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 1
n=74 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=69 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Geometric Mean Titer (GMT) of Hemagglutination Inhibition (HI) Antibodies Against the H5N6 Strain
Day 1
5.47 titer
Interval 5.12 to 5.85
5.48 titer
Interval 5.07 to 5.92
5.55 titer
Interval 5.13 to 6.01
Geometric Mean Titer (GMT) of Hemagglutination Inhibition (HI) Antibodies Against the H5N6 Strain
Day 8
7.97 titer
Interval 6.21 to 10.23
20.39 titer
Interval 15.22 to 27.33
23.67 titer
Interval 17.47 to 32.06
Geometric Mean Titer (GMT) of Hemagglutination Inhibition (HI) Antibodies Against the H5N6 Strain
Day 22
12.14 titer
Interval 9.3 to 15.85
46.89 titer
Interval 34.62 to 63.5
66.73 titer
Interval 48.85 to 91.14
Geometric Mean Titer (GMT) of Hemagglutination Inhibition (HI) Antibodies Against the H5N6 Strain
Day 43
30.76 titer
Interval 23.78 to 39.79
58.16 titer
Interval 43.21 to 78.28
50.55 titer
Interval 37.21 to 68.68

PRIMARY outcome

Timeframe: Day 1, Day 8, Day 22, Day 43

Population: Per-protocol set defined as all subjects who correctly received the study vaccine, provided at least one evaluable serum sample at relevant timepoints, had no major protocol deviations leading to exclusion, and were not excluded due to other reasons prior to unblinding or analysis.

GMFI 1 and 3 weeks post-vaccination 1, and 3 weeks post-vaccination 2 compared to pre-vaccination (Day 1) Note: The Overall Number of Participants Analyzed (N) represents the total number of participants in the PPS; definitions are provided in the SAP. The Number Analyzed (n) at each timepoint corresponds to the number of participants with an available serum analysis result for the relevant strain at that timepoint. Instances where n\<N reflect missing serum samples or non-evaluable results. All participants included in the Overall Number of Participants Analyzed contributed data to the analysis at one or more timepoints.

Outcome measures

Outcome measures
Measure
Group 3
n=92 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 1
n=72 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=66 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Geometric Mean Fold Increase (GMFI) of HI Antibodies Against the H5N6 Strain
Day 8 / Day 1
1.45 ratio
Interval 1.13 to 1.86
3.71 ratio
Interval 2.77 to 4.98
4.31 ratio
Interval 3.18 to 5.84
Geometric Mean Fold Increase (GMFI) of HI Antibodies Against the H5N6 Strain
Day 22 / Day 1
2.21 ratio
Interval 1.69 to 2.88
8.52 ratio
Interval 6.29 to 11.54
12.13 ratio
Interval 8.88 to 16.57
Geometric Mean Fold Increase (GMFI) of HI Antibodies Against the H5N6 Strain
Day 43 / Day 1
5.58 ratio
Interval 4.31 to 7.21
10.54 ratio
Interval 7.83 to 14.19
9.16 ratio
Interval 6.74 to 12.45

PRIMARY outcome

Timeframe: Day 1, Day 8, Day 22, Day 43

Population: Per-protocol set defined as all subjects who correctly received the study vaccine, provided at least one evaluable serum sample at relevant timepoints, had no major protocol deviations leading to exclusion, and were not excluded due to other reasons prior to unblinding or analysis.

Pre-vaccination, 1 and 3 weeks post-vaccination 1, and 3 weeks post-vaccination 2 Note: The Overall Number of Participants Analyzed (N) represents the total number of participants in the PPS; definitions are provided in the SAP. The Number Analyzed (n) at each timepoint corresponds to the number of participants with an available serum analysis result for the relevant strain at that timepoint. Instances where n\<N reflect missing serum samples or non-evaluable results. All participants included in the Overall Number of Participants Analyzed contributed data to the analysis at one or more timepoints.

Outcome measures

Outcome measures
Measure
Group 3
n=95 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 1
n=74 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=69 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Percentage of Subjects With HI Titers ≥1:40 Against the H5N6 Strain
Day 1
1.1 % of participants
Interval 0.03 to 5.91
0.0 % of participants
Interval 0.0 to 4.99
0.0 % of participants
Interval 0.0 to 5.44
Percentage of Subjects With HI Titers ≥1:40 Against the H5N6 Strain
Day 8
9.9 % of participants
Interval 4.62 to 17.95
29.4 % of participants
Interval 18.98 to 41.71
39.1 % of participants
Interval 27.1 to 52.07
Percentage of Subjects With HI Titers ≥1:40 Against the H5N6 Strain
Day 22
20.7 % of participants
Interval 12.92 to 30.36
60.8 % of participants
Interval 48.77 to 71.96
65.2 % of participants
Interval 52.79 to 76.29
Percentage of Subjects With HI Titers ≥1:40 Against the H5N6 Strain
Day 43
50.0 % of participants
Interval 39.39 to 60.61
73.2 % of participants
Interval 61.41 to 83.06
59.1 % of participants
Interval 46.29 to 71.05

PRIMARY outcome

Timeframe: Day 8, Day 22, Day 43

Population: Per-protocol set defined as all subjects who correctly received the study vaccine, provided at least one evaluable serum sample at relevant timepoints, had no major protocol deviations leading to exclusion, and were not excluded due to other reasons prior to unblinding or analysis.

Seroconversion 1 and 3 weeks post-vaccination 1, and 3 weeks post-vaccination 2, defined as a ≥4-fold increase in HI titer post-vaccination in those with pre-vaccination titer ≥1:10, or a post-vaccination HI titer ≥1:40 for subjects with baseline titer \<1:10 Note: The Overall Number of Participants Analyzed (N) represents the total number of participants in the PPS; definitions are provided in the SAP. The Number Analyzed (n) at each timepoint corresponds to the number of participants with an available serum analysis result for the relevant strain at that timepoint. Instances where n\<N reflect missing serum samples or non-evaluable results. All participants included in the Overall Number of Participants Analyzed contributed data to the analysis at one or more timepoints.

Outcome measures

Outcome measures
Measure
Group 3
n=92 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 1
n=72 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=66 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Percentage of Subjects With Seroconversion Against the H5N6 Strain
Day 8
8.9 % of participants
Interval 3.92 to 16.77
28.4 % of participants
Interval 18.01 to 40.69
36.1 % of participants
Interval 24.16 to 49.37
Percentage of Subjects With Seroconversion Against the H5N6 Strain
Day 22
18.9 % of participants
Interval 11.41 to 28.51
59.7 % of participants
Interval 47.5 to 71.12
63.6 % of participants
Interval 50.87 to 75.13
Percentage of Subjects With Seroconversion Against the H5N6 Strain
Day 43
47.2 % of participants
Interval 36.51 to 58.06
71.0 % of participants
Interval 58.84 to 81.31
55.6 % of participants
Interval 42.49 to 68.08

SECONDARY outcome

Timeframe: Day 1, Day 8, Day 22, Day 43, Day 202

Population: Per-protocol set defined as all subjects who correctly received the study vaccine, provided at least one evaluable serum sample at relevant timepoints, had no major protocol deviations leading to exclusion, and were not excluded due to other reasons prior to unblinding or analysis.

GMT pre-vaccination, 1 and 3 weeks post-vaccination 1, and 3 weeks and 6 months post-vaccination 2 Note: The Overall Number of Participants Analyzed (N) represents the total number of participants in the PPS; definitions are provided in the SAP. The Number Analyzed (n) at each timepoint corresponds to the number of participants with an available serum analysis result for the relevant strain at that timepoint. Instances where n\<N reflect missing serum samples or non-evaluable results. All participants included in the Overall Number of Participants Analyzed contributed data to the analysis at one or more timepoints.

Outcome measures

Outcome measures
Measure
Group 3
n=91 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 1
n=74 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=69 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
GMT of HI Antibodies Against the H5N1 Strain
Day 1
6.89 titer
Interval 5.86 to 8.11
13.16 titer
Interval 10.91 to 15.87
15.54 titer
Interval 12.83 to 18.83
GMT of HI Antibodies Against the H5N1 Strain
Day 8
14.81 titer
Interval 11.43 to 19.2
115.14 titer
Interval 85.71 to 154.69
122.91 titer
Interval 90.05 to 167.75
GMT of HI Antibodies Against the H5N1 Strain
Day 22
17.95 titer
Interval 13.59 to 23.71
345.46 titer
Interval 255.76 to 466.61
428.42 titer
Interval 312.86 to 586.67
GMT of HI Antibodies Against the H5N1 Strain
Day 43
23.15 titer
Interval 17.7 to 30.28
333.37 titer
Interval 250.37 to 443.87
343.48 titer
Interval 253.5 to 465.4
GMT of HI Antibodies Against the H5N1 Strain
Day 202
15.86 titer
Interval 12.43 to 20.25
122.10 titer
Interval 93.95 to 158.67
99.22 titer
Interval 75.66 to 130.12

SECONDARY outcome

Timeframe: Day 1, Day 8, Day 22, Day 43, Day 202

Population: Per-protocol set defined as all subjects who correctly received the study vaccine, provided at least one evaluable serum sample at relevant timepoints, had no major protocol deviations leading to exclusion, and were not excluded due to other reasons prior to unblinding or analysis.

GMFI 1 and 3 weeks post-vaccination 1, and 3 weeks and 6 months post-vaccination 2 compared to pre-vaccination (Day 1) Note: The Overall Number of Participants Analyzed (N) represents the total number of participants in the PPS; definitions are provided in the SAP. The Number Analyzed (n) at each timepoint corresponds to the number of participants with an available serum analysis result for the relevant strain at that timepoint. Instances where n\<N reflect missing serum samples or non-evaluable results. All participants included in the Overall Number of Participants Analyzed contributed data to the analysis at one or more timepoints.

Outcome measures

Outcome measures
Measure
Group 3
n=88 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 1
n=68 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=63 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
GMFI of HI Antibodies Against the H5N1 Strain
Day 8 / Day 1
1.43 ratio
Interval 1.1 to 1.86
11.13 ratio
Interval 8.28 to 14.95
11.88 ratio
Interval 8.7 to 16.21
GMFI of HI Antibodies Against the H5N1 Strain
Day 22 / Day 1
1.66 ratio
Interval 1.26 to 2.19
31.97 ratio
Interval 23.67 to 43.18
39.65 ratio
Interval 28.95 to 54.29
GMFI of HI Antibodies Against the H5N1 Strain
Day 43 / Day 1
2.14 ratio
Interval 1.63 to 2.8
30.78 ratio
Interval 23.12 to 40.98
31.71 ratio
Interval 23.4 to 42.97
GMFI of HI Antibodies Against the H5N1 Strain
Day 202 / Day 1
1.44 ratio
Interval 1.13 to 1.84
11.07 ratio
Interval 8.52 to 14.38
8.99 ratio
Interval 6.86 to 11.8

SECONDARY outcome

Timeframe: Day 1, Day 8, Day 22, Day 43, Day 202

Population: Per-protocol set defined as all subjects who correctly received the study vaccine, provided at least one evaluable serum sample at relevant timepoints, had no major protocol deviations leading to exclusion, and were not excluded due to other reasons prior to unblinding or analysis.

Pre-vaccination, 1 and 3 weeks post-vaccination 1, and 3 weeks and 6 months post-vaccination 2 Note: The Overall Number of Participants Analyzed (N) represents the total number of participants in the PPS; definitions are provided in the SAP. The Number Analyzed (n) at each timepoint corresponds to the number of participants with an available serum analysis result for the relevant strain at that timepoint. Instances where n\<N reflect missing serum samples or non-evaluable results. All participants included in the Overall Number of Participants Analyzed contributed data to the analysis at one or more timepoints.

Outcome measures

Outcome measures
Measure
Group 3
n=91 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 1
n=74 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=69 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Percentage of Subjects With HI Titers ≥1:40 Against the H5N1 Strain
Day 1
2.3 % of participants
Interval 0.28 to 7.97
13.2 % of participants
Interval 6.23 to 23.64
23.8 % of participants
Interval 13.98 to 36.21
Percentage of Subjects With HI Titers ≥1:40 Against the H5N1 Strain
Day 8
10.1 % of participants
Interval 4.73 to 18.33
83.8 % of participants
Interval 72.9 to 91.64
81.3 % of participants
Interval 69.54 to 89.92
Percentage of Subjects With HI Titers ≥1:40 Against the H5N1 Strain
Day 22
12.6 % of participants
Interval 6.48 to 21.5
91.9 % of participants
Interval 83.18 to 96.97
97.1 % of participants
Interval 89.92 to 99.65
Percentage of Subjects With HI Titers ≥1:40 Against the H5N1 Strain
Day 43
20.0 % of participants
Interval 12.1 to 30.08
93.1 % of participants
Interval 84.53 to 97.71
90.9 % of participants
Interval 81.26 to 96.59
Percentage of Subjects With HI Titers ≥1:40 Against the H5N1 Strain
Day 202
9.6 % of participants
Interval 4.25 to 18.11
82.9 % of participants
Interval 71.97 to 90.82
81.8 % of participants
Interval 70.39 to 90.24

SECONDARY outcome

Timeframe: Day 8, Day 22, Day 43, Day 202

Population: Per-protocol set defined as all subjects who correctly received the study vaccine, provided at least one evaluable serum sample at relevant timepoints, had no major protocol deviations leading to exclusion, and were not excluded due to other reasons prior to unblinding or analysis.

Seroconversion 1 and 3 weeks post-vaccination 1, and 3 weeks and 6 months post-vaccination 2, defined as a ≥4-fold increase in HI titer post-vaccination in those with pre-vaccination titer ≥1:10, or a post-vaccination HI titer ≥1:40 for subjects with baseline titer \<1:10 Note: The Overall Number of Participants Analyzed (N) represents the total number of participants in the PPS; definitions are provided in the SAP. The Number Analyzed (n) at each timepoint corresponds to the number of participants with an available serum analysis result for the relevant strain at that timepoint. Instances where n\<N reflect missing serum samples or non-evaluable results. All participants included in the Overall Number of Participants Analyzed contributed data to the analysis at one or more timepoints.

Outcome measures

Outcome measures
Measure
Group 3
n=88 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 1
n=68 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=63 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Percentage of Subjects With Seroconversion Against the H5N1 Strain
Day 8
8.0 % of participants
Interval 3.3 to 15.88
77.8 % of participants
Interval 65.54 to 87.28
72.4 % of participants
Interval 59.1 to 83.34
Percentage of Subjects With Seroconversion Against the H5N1 Strain
Day 22
9.4 % of participants
Interval 4.15 to 17.71
89.7 % of participants
Interval 79.93 to 95.76
96.8 % of participants
Interval 89.0 to 99.61
Percentage of Subjects With Seroconversion Against the H5N1 Strain
Day 43
13.4 % of participants
Interval 6.89 to 22.74
89.6 % of participants
Interval 79.65 to 95.7
90.2 % of participants
Interval 79.81 to 96.3
Percentage of Subjects With Seroconversion Against the H5N1 Strain
Day 202
6.3 % of participants
Interval 2.06 to 13.99
73.8 % of participants
Interval 61.46 to 83.97
75.4 % of participants
Interval 62.71 to 85.54

SECONDARY outcome

Timeframe: Day 202

Population: Per-protocol set defined as all subjects who correctly received the study vaccine, provided at least one evaluable serum sample at relevant timepoints, had no major protocol deviations leading to exclusion, and were not excluded due to other reasons prior to unblinding or analysis.

GMT 6 months post-vaccination 2

Outcome measures

Outcome measures
Measure
Group 3
n=85 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 1
n=68 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=66 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
GMT of HI Antibodies Against the H5N6 Strain
10.05 titer
Interval 8.14 to 12.4
21.18 titer
Interval 16.69 to 26.89
19.35 titer
Interval 15.2 to 24.64

SECONDARY outcome

Timeframe: Day 1, Day 202

Population: Per-protocol set defined as all subjects who correctly received the study vaccine, provided at least one evaluable serum sample at relevant timepoints, had no major protocol deviations leading to exclusion, and were not excluded due to other reasons prior to unblinding or analysis.

GMFI 6 months post-vaccination 2 compared to pre-vaccination (Day 1)

Outcome measures

Outcome measures
Measure
Group 3
n=83 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 1
n=67 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=63 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
GMFI of HI Antibodies Against the H5N6 Strain
1.81 ratio
Interval 1.47 to 2.24
3.82 ratio
Interval 3.01 to 4.85
3.49 ratio
Interval 2.74 to 4.45

SECONDARY outcome

Timeframe: Day 202

Population: Per-protocol set defined as all subjects who correctly received the study vaccine, provided at least one evaluable serum sample at relevant timepoints, had no major protocol deviations leading to exclusion, and were not excluded due to other reasons prior to unblinding or analysis.

6 months post-vaccination 2

Outcome measures

Outcome measures
Measure
Group 3
n=85 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 1
n=68 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=66 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Percentage of Subjects With HI Titers ≥1:40 Against the H5N6 Strain
11.8 % of participants
Interval 5.79 to 20.57
39.7 % of participants
Interval 28.03 to 52.3
30.3 % of participants
Interval 19.59 to 42.85

SECONDARY outcome

Timeframe: Day 202

Population: Per-protocol set defined as all subjects who correctly received the study vaccine, provided at least one evaluable serum sample at relevant timepoints, had no major protocol deviations leading to exclusion, and were not excluded due to other reasons prior to unblinding or analysis.

Seroconversion 6 months post-vaccination 2, defined as a ≥4-fold increase in HI titer post-vaccination in those with pre-vaccination titer ≥1:10, or a post-vaccination HI titer ≥1:40 for subjects with baseline titer \<1:10

Outcome measures

Outcome measures
Measure
Group 3
n=83 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 1
n=67 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=63 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Percentage of Subjects With Seroconversion Against the H5N6 Strain
9.6 % of participants
Interval 4.25 to 18.11
37.3 % of participants
Interval 25.8 to 49.99
30.2 % of participants
Interval 19.23 to 43.02

SECONDARY outcome

Timeframe: Day 1 through Day 7 and Day 22 through Day 28

Population: Solicited Safety Set defined as all subjects in the All Exposed Set with any solicited AE data and/or indicators of solicited AEs.

For 7 days following each vaccination

Outcome measures

Outcome measures
Measure
Group 3
n=100 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 1
n=79 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=76 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Frequency and Severity of Solicited Local and Systemic Adverse Events (AEs)
Solicited Systemic AEs
36 Participants
26 Participants
34 Participants
Frequency and Severity of Solicited Local and Systemic Adverse Events (AEs)
Solicited Systemic AEs - Severe
2 Participants
2 Participants
1 Participants
Frequency and Severity of Solicited Local and Systemic Adverse Events (AEs)
Analgesic/antipyretic Use
13 Participants
8 Participants
5 Participants
Frequency and Severity of Solicited Local and Systemic Adverse Events (AEs)
Solicited AEs (Overall)
67 Participants
54 Participants
48 Participants
Frequency and Severity of Solicited Local and Systemic Adverse Events (AEs)
Solicited Local AEs
60 Participants
51 Participants
38 Participants
Frequency and Severity of Solicited Local and Systemic Adverse Events (AEs)
Solicited Local AEs - Severe
0 Participants
0 Participants
2 Participants

SECONDARY outcome

Timeframe: Day 1 through Day 43

Population: Unsolicited Safety Set defined as all subjects in the All Exposed Set with unsolicited AE data, including confirmation of absence of unsolicited AEs.

For 3 weeks following each vaccination

Outcome measures

Outcome measures
Measure
Group 3
n=100 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 1
n=80 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=78 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Frequency and Severity of Unsolicited AEs
Unsolicited AEs - Severe
0 Participants
1 Participants
1 Participants
Frequency and Severity of Unsolicited AEs
Unsolicited AEs - Mild
18 Participants
8 Participants
11 Participants
Frequency and Severity of Unsolicited AEs
Unsolicited AEs - Moderate
7 Participants
14 Participants
9 Participants
Frequency and Severity of Unsolicited AEs
Unsolicited AEs (Overall)
25 Participants
23 Participants
21 Participants

SECONDARY outcome

Timeframe: Day 1 through Day 202

Population: Unsolicited Safety Set defined a all subjects in the All Exposed Set with unsolicited AE data, including confirmation of absence of unsolicited AEs.

From vaccination until study completion

Outcome measures

Outcome measures
Measure
Group 3
n=100 Participants
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 1
n=80 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=78 Participants
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Frequency of Serious AEs (SAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESI) and Medically Attended AEs (MAAEs)
SAE
4 Participants
3 Participants
3 Participants
Frequency of Serious AEs (SAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESI) and Medically Attended AEs (MAAEs)
MAAE
28 Participants
22 Participants
21 Participants
Frequency of Serious AEs (SAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESI) and Medically Attended AEs (MAAEs)
AESI
0 Participants
0 Participants
0 Participants
Frequency of Serious AEs (SAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESI) and Medically Attended AEs (MAAEs)
AE leading to withdrawal from treatment
1 Participants
0 Participants
0 Participants
Frequency of Serious AEs (SAEs), AEs Leading to Withdrawal, AEs of Special Interest (AESI) and Medically Attended AEs (MAAEs)
AE leading to withdrawal from study
0 Participants
1 Participants
0 Participants

Adverse Events

Group 1

Serious events: 3 serious events
Other events: 12 other events
Deaths: 1 deaths

Group 2

Serious events: 3 serious events
Other events: 5 other events
Deaths: 0 deaths

Group 3

Serious events: 4 serious events
Other events: 7 other events
Deaths: 0 deaths

Serious adverse events

Serious adverse events
Measure
Group 1
n=80 participants at risk
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=78 participants at risk
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Group 3
n=100 participants at risk
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Cardiac disorders
Hypertensive heart disease
1.2%
1/80 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
0.00%
0/78 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
0.00%
0/100 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
Hepatobiliary disorders
Cholecystitis
0.00%
0/80 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
1.3%
1/78 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
0.00%
0/100 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
Metabolism and nutrition disorders
Type 2 diabetes mellitus
0.00%
0/80 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
1.3%
1/78 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
0.00%
0/100 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
Musculoskeletal and connective tissue disorders
Osteoarthritis
0.00%
0/80 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
0.00%
0/78 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
1.0%
1/100 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
Neoplasms benign, malignant and unspecified (incl cysts and polyps)
Brain neoplasm
1.2%
1/80 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
0.00%
0/78 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
0.00%
0/100 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
Neoplasms benign, malignant and unspecified (incl cysts and polyps)
Glioblastoma
0.00%
0/80 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
0.00%
0/78 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
1.0%
1/100 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
Neoplasms benign, malignant and unspecified (incl cysts and polyps)
Mantle cell lymphoma
0.00%
0/80 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
1.3%
1/78 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
1.0%
1/100 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
Nervous system disorders
Seizure
1.2%
1/80 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
0.00%
0/78 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
0.00%
0/100 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
Respiratory, thoracic and mediastinal disorders
Acute respiratory failure
1.2%
1/80 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
0.00%
0/78 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
0.00%
0/100 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
Respiratory, thoracic and mediastinal disorders
Asthma
0.00%
0/80 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
0.00%
0/78 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
1.0%
1/100 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
Vascular disorders
Arteriosclerosis
1.2%
1/80 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
0.00%
0/78 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
0.00%
0/100 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.

Other adverse events

Other adverse events
Measure
Group 1
n=80 participants at risk
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
Group 2
n=78 participants at risk
Eligible subjects who received 2 doses of aH5N1c in the parent study V89\_18 randomized to receive an aH5N6c vaccination on Day 1 and saline placebo on Day 22
Group 3
n=100 participants at risk
Eligible subjects who received placebo in the parent study V89\_18 planned to receive two aH5N6c vaccinations, 3 weeks apart on Day 1 and Day 22
General disorders
Injection site bruising
6.2%
5/80 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
3.8%
3/78 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
4.0%
4/100 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
Infections and infestations
COVID-19
8.8%
7/80 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
3.8%
3/78 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.
3.0%
3/100 • SAEs, AEs leading to withdrawal from the study, adverse events of special interest (AESIs), and MAAEs Day 1 through Day 202, other AEs Day 1 through Day 43
AEs were collected as either solicited or unsolicited AEs. Solicited AEs were derived from subject diaries. Unsolicited AEs were spontaneously communicated by the subject.

Additional Information

CSL Seqirus Clinical Trial Manager

CSL Seqirus

Phone: 1-855-358-8966

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place