Trial Outcomes & Findings for Comparative Immunogenicity of Concomitant vs Sequential mRNA COVID-19 and Influenza Vaccinations (NCT NCT06020118)
NCT ID: NCT06020118
Last Updated: 2025-06-13
Results Overview
Number of participants with a seroconversion HAI Titer ≥1:40 at Day 29 if Day 1 titer is \<1:10 or a four-fold rise at Day 29 if Day 1 titer is ≥1:10 for each ccIIV4 antigen in the 2023-2024 influenza season.
Recruitment status
COMPLETED
Study phase
PHASE4
Target enrollment
455 participants
Primary outcome timeframe
Visit 1 (day 1; baseline) to Visit 2 (days 28-42; post-vaccination) for all arms/groups
Results posted on
2025-06-13
Participant Flow
455 participants were enrolled and consented. 8 participants were not randomized to a vaccine group due to being screen fails. 447 participants were randomized to Group i, Group ii, or Group iii.
Participant milestones
| Measure |
Group i: Concomitant Vaccination at Visit 1
Simultaneous Vaccination (Influenza vaccine and mRNA COVID booster) at Visit 1
Simultaneous Vaccination (Influenza Vaccine and mRNA COVID booster): Influenza vaccination and mRNA COVID-19 booster will be given at Visit 1.
|
Group ii: Influenza Vaccination at Visit 1
Sequential vaccination with Influenza vaccination at Visit 1 and mRNA COVID booster at Visit 2
Sequential Vaccination (Influenza vaccine then mRNA COVID booster): Influenza vaccine will be given at Visit 1 and mRNA COVID booster will be given at Visit 2.
|
Group Iii: mRNA COVID-19 Vaccination at Visit 1
Sequential vaccination with mRNA COVID booster at Visit 1 and Influenza vaccination at Visit 2
Sequential Vaccination (mRNA COVID booster then Influenza vaccine): mRNA COVID booster will be given at Visit 1 and Influenza vaccine will be given at Visit 2.
|
|---|---|---|---|
|
Overall Study
STARTED
|
223
|
111
|
113
|
|
Overall Study
COMPLETED
|
219
|
102
|
111
|
|
Overall Study
NOT COMPLETED
|
4
|
9
|
2
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
One Participant in Group i: Missing Age
Baseline characteristics by cohort
| Measure |
Group i: Concomitant Vaccination
n=223 Participants
Simultaneous Vaccination (Influenza vaccine and mRNA COVID booster) at Visit 1
Simultaneous Vaccination (Influenza Vaccine and mRNA COVID booster): Influenza vaccination and mRNA COVID-19 booster will be given at Visit 1.
|
Group ii: Influenza Vaccination
n=111 Participants
Sequential vaccination with Influenza vaccination at Visit 1 and mRNA COVID booster at Visit 2
Sequential Vaccination (Influenza vaccine then mRNA COVID booster): Influenza vaccine will be given at Visit 1 and mRNA COVID booster will be given at Visit 2.
|
Group Iii: mRNA COVID-19 Vaccination
n=113 Participants
Sequential vaccination with mRNA COVID booster at Visit 1 and Influenza vaccination at Visit 2
Sequential Vaccination (mRNA COVID booster then Influenza vaccine): mRNA COVID booster will be given at Visit 1 and Influenza vaccine will be given at Visit 2.
|
Total
n=447 Participants
Total of all reporting groups
|
|---|---|---|---|---|
|
Age, Customized
Age Group · 6-11 Years
|
5 Participants
n=223 Participants
|
3 Participants
n=111 Participants
|
3 Participants
n=113 Participants
|
11 Participants
n=447 Participants
|
|
Age, Customized
Age Group · 18-49 Years
|
174 Participants
n=223 Participants
|
85 Participants
n=111 Participants
|
84 Participants
n=113 Participants
|
343 Participants
n=447 Participants
|
|
Age, Customized
Age Group · 50-64 Years
|
43 Participants
n=223 Participants
|
23 Participants
n=111 Participants
|
26 Participants
n=113 Participants
|
92 Participants
n=447 Participants
|
|
Age, Customized
Age Group · Unknown
|
1 Participants
n=223 Participants
|
0 Participants
n=111 Participants
|
0 Participants
n=113 Participants
|
1 Participants
n=447 Participants
|
|
Age, Customized
Age (Years), Median
|
33 Years
n=222 Participants • One Participant in Group i: Missing Age
|
32 Years
n=111 Participants • One Participant in Group i: Missing Age
|
34 Years
n=113 Participants • One Participant in Group i: Missing Age
|
33 Years
n=446 Participants • One Participant in Group i: Missing Age
|
|
Sex: Female, Male
Female
|
135 Participants
n=219 Participants • Four Participants in Group i: Missing Sex
|
61 Participants
n=111 Participants • Four Participants in Group i: Missing Sex
|
65 Participants
n=113 Participants • Four Participants in Group i: Missing Sex
|
261 Participants
n=443 Participants • Four Participants in Group i: Missing Sex
|
|
Sex: Female, Male
Male
|
84 Participants
n=219 Participants • Four Participants in Group i: Missing Sex
|
50 Participants
n=111 Participants • Four Participants in Group i: Missing Sex
|
48 Participants
n=113 Participants • Four Participants in Group i: Missing Sex
|
182 Participants
n=443 Participants • Four Participants in Group i: Missing Sex
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
37 Participants
n=223 Participants
|
16 Participants
n=111 Participants
|
16 Participants
n=113 Participants
|
69 Participants
n=447 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
182 Participants
n=223 Participants
|
95 Participants
n=111 Participants
|
94 Participants
n=113 Participants
|
371 Participants
n=447 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
4 Participants
n=223 Participants
|
0 Participants
n=111 Participants
|
3 Participants
n=113 Participants
|
7 Participants
n=447 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
0 Participants
n=223 Participants
|
0 Participants
n=111 Participants
|
1 Participants
n=113 Participants
|
1 Participants
n=447 Participants
|
|
Race (NIH/OMB)
Asian
|
33 Participants
n=223 Participants
|
14 Participants
n=111 Participants
|
17 Participants
n=113 Participants
|
64 Participants
n=447 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
1 Participants
n=223 Participants
|
0 Participants
n=111 Participants
|
0 Participants
n=113 Participants
|
1 Participants
n=447 Participants
|
|
Race (NIH/OMB)
Black or African American
|
12 Participants
n=223 Participants
|
6 Participants
n=111 Participants
|
7 Participants
n=113 Participants
|
25 Participants
n=447 Participants
|
|
Race (NIH/OMB)
White
|
155 Participants
n=223 Participants
|
78 Participants
n=111 Participants
|
84 Participants
n=113 Participants
|
317 Participants
n=447 Participants
|
|
Race (NIH/OMB)
More than one race
|
7 Participants
n=223 Participants
|
4 Participants
n=111 Participants
|
0 Participants
n=113 Participants
|
11 Participants
n=447 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
15 Participants
n=223 Participants
|
9 Participants
n=111 Participants
|
4 Participants
n=113 Participants
|
28 Participants
n=447 Participants
|
|
Enrollment Site
Arizona State University
|
66 Participants
n=223 Participants
|
32 Participants
n=111 Participants
|
33 Participants
n=113 Participants
|
131 Participants
n=447 Participants
|
|
Enrollment Site
Cleveland Veterans Affairs
|
12 Participants
n=223 Participants
|
5 Participants
n=111 Participants
|
6 Participants
n=113 Participants
|
23 Participants
n=447 Participants
|
|
Enrollment Site
Senders Pediatrics
|
1 Participants
n=223 Participants
|
1 Participants
n=111 Participants
|
1 Participants
n=113 Participants
|
3 Participants
n=447 Participants
|
|
Enrollment Site
University Hospitals Cleveland
|
30 Participants
n=223 Participants
|
15 Participants
n=111 Participants
|
15 Participants
n=113 Participants
|
60 Participants
n=447 Participants
|
|
Enrollment Site
University of Pittsburgh
|
77 Participants
n=223 Participants
|
39 Participants
n=111 Participants
|
39 Participants
n=113 Participants
|
155 Participants
n=447 Participants
|
|
Enrollment Site
Valleywise Health
|
12 Participants
n=223 Participants
|
7 Participants
n=111 Participants
|
6 Participants
n=113 Participants
|
25 Participants
n=447 Participants
|
|
Enrollment Site
Washington University at St. Louis
|
25 Participants
n=223 Participants
|
12 Participants
n=111 Participants
|
13 Participants
n=113 Participants
|
50 Participants
n=447 Participants
|
PRIMARY outcome
Timeframe: Visit 1 (day 1; baseline) to Visit 2 (days 28-42; post-vaccination) for all arms/groupsPopulation: Influenza Immunogenicity Population: Subset of the modified intention-to-treat (mITT) Population that includes only subjects who received both vaccines, provide visit 1 and visit 2 blood draws available with HAI titer results for analysis within the protocol-defined time frame, did not have an influenza or SARS-CoV-2 infection between visits 1 and 2, and had no protocol violations affecting immunogenicity.
Number of participants with a seroconversion HAI Titer ≥1:40 at Day 29 if Day 1 titer is \<1:10 or a four-fold rise at Day 29 if Day 1 titer is ≥1:10 for each ccIIV4 antigen in the 2023-2024 influenza season.
Outcome measures
| Measure |
Group i
n=197 Participants
Simultaneous Vaccination (Influenza vaccine and mRNA COVID booster) at Visit 1
Simultaneous Vaccination (Influenza Vaccine and mRNA COVID booster): Influenza vaccination and mRNA COVID-19 booster will be given at Visit 1.
|
Group ii
n=95 Participants
Sequential vaccination with Influenza vaccination at Visit 1 and mRNA COVID booster at Visit 2
Sequential Vaccination (Influenza vaccine then mRNA COVID booster): Influenza vaccine will be given at Visit 1 and mRNA COVID booster will be given at Visit 2.
|
Group Iii
n=107 Participants
Sequential vaccination with mRNA COVID booster at Visit 1 and Influenza vaccination at Visit 2
Sequential Vaccination (mRNA COVID booster then Influenza vaccine): mRNA COVID booster will be given at Visit 1 and Influenza vaccine will be given at Visit 2.
|
|---|---|---|---|
|
Percentage of Participants With HAI Seroconversion
A(H1N1)pdm09
|
53.3 percentage of participants
Interval 46.1 to 60.4
|
52.6 percentage of participants
Interval 42.1 to 63.0
|
0.9 percentage of participants
Interval 0.02 to 5.1
|
|
Percentage of Participants With HAI Seroconversion
B/Victoria
|
47.7 percentage of participants
Interval 40.6 to 54.9
|
48.4 percentage of participants
Interval 38.0 to 58.9
|
4.7 percentage of participants
Interval 1.5 to 10.6
|
|
Percentage of Participants With HAI Seroconversion
B/Yamagata
|
18.8 percentage of participants
Interval 13.6 to 25.0
|
14.7 percentage of participants
Interval 8.3 to 23.5
|
1.9 percentage of participants
Interval 0.2 to 6.6
|
|
Percentage of Participants With HAI Seroconversion
A(H3N2)
|
33.5 percentage of participants
Interval 27.0 to 40.6
|
36.8 percentage of participants
Interval 27.2 to 47.4
|
1.9 percentage of participants
Interval 0.2 to 6.6
|
PRIMARY outcome
Timeframe: Visit 1 (day 1; baseline; pre-immunization) and Visit 2 (days 28-42; post-immunization) for all arms/groupsPopulation: Influenza Immunogenicity Population: Subset of the mITT Population that includes only subjects who received both vaccines, provide visit 1 and visit 2 blood draws available with HAI titer results for analysis within the protocol-defined time frame, did not have an influenza or SARS-CoV-2 infection between visits 1 and 2, and had no protocol violations affecting immunogenicity.
Number of participants with a seroprotective HAI titer (≥ 1:40) pre- and post-immunization at day 29 for each ccIIV4 antigen in the 2023-2024 influenza season.
Outcome measures
| Measure |
Group i
n=197 Participants
Simultaneous Vaccination (Influenza vaccine and mRNA COVID booster) at Visit 1
Simultaneous Vaccination (Influenza Vaccine and mRNA COVID booster): Influenza vaccination and mRNA COVID-19 booster will be given at Visit 1.
|
Group ii
n=95 Participants
Sequential vaccination with Influenza vaccination at Visit 1 and mRNA COVID booster at Visit 2
Sequential Vaccination (Influenza vaccine then mRNA COVID booster): Influenza vaccine will be given at Visit 1 and mRNA COVID booster will be given at Visit 2.
|
Group Iii
n=107 Participants
Sequential vaccination with mRNA COVID booster at Visit 1 and Influenza vaccination at Visit 2
Sequential Vaccination (mRNA COVID booster then Influenza vaccine): mRNA COVID booster will be given at Visit 1 and Influenza vaccine will be given at Visit 2.
|
|---|---|---|---|
|
Percentage of Participants With HAI Seroprotection
A(H1N1)pdm09
|
88.3 percentage of participants
Interval 83.0 to 92.5
|
87.4 percentage of participants
Interval 79.0 to 93.3
|
58.9 percentage of participants
Interval 49.0 to 68.3
|
|
Percentage of Participants With HAI Seroprotection
A(H3N2)
|
71.1 percentage of participants
Interval 64.2 to 77.3
|
80.0 percentage of participants
Interval 70.5 to 87.5
|
36.5 percentage of participants
Interval 27.4 to 46.3
|
|
Percentage of Participants With HAI Seroprotection
B/Victoria
|
84.3 percentage of participants
Interval 78.4 to 89.1
|
85.3 percentage of participants
Interval 76.5 to 91.7
|
38.3 percentage of participants
Interval 29.1 to 48.2
|
|
Percentage of Participants With HAI Seroprotection
B/Yamagata
|
95.4 percentage of participants
Interval 91.5 to 97.9
|
97.9 percentage of participants
Interval 92.6 to 99.7
|
87.8 percentage of participants
Interval 80.2 to 93.4
|
PRIMARY outcome
Timeframe: Visit 1 (day 1; baseline; pre-immunization) and Visit 2 (days 28-42; post-immunization) for all arms/groupsPopulation: Influenza Immunogenicity Population: Subset of the mITT Population that includes only subjects who received both vaccines, provide visit 1 and visit 2 blood draws available with HAI titer results for analysis within the protocol-defined time frame, did not have an influenza or SARS-CoV-2 infection between visits 1 and 2, and had no protocol violations affecting immunogenicity.
The geometric mean HAI titer (GMT) for each ccIIV4 antigen in the 2023-2024 influenza season. GMTs were derived by using the anti-log of the mean of the log transformed titers.
Outcome measures
| Measure |
Group i
n=197 Participants
Simultaneous Vaccination (Influenza vaccine and mRNA COVID booster) at Visit 1
Simultaneous Vaccination (Influenza Vaccine and mRNA COVID booster): Influenza vaccination and mRNA COVID-19 booster will be given at Visit 1.
|
Group ii
n=95 Participants
Sequential vaccination with Influenza vaccination at Visit 1 and mRNA COVID booster at Visit 2
Sequential Vaccination (Influenza vaccine then mRNA COVID booster): Influenza vaccine will be given at Visit 1 and mRNA COVID booster will be given at Visit 2.
|
Group Iii
n=107 Participants
Sequential vaccination with mRNA COVID booster at Visit 1 and Influenza vaccination at Visit 2
Sequential Vaccination (mRNA COVID booster then Influenza vaccine): mRNA COVID booster will be given at Visit 1 and Influenza vaccine will be given at Visit 2.
|
|---|---|---|---|
|
HAI Geometric Mean Titer
Pre-vaccine: A(H1N1)pdm09
|
31.7 Titer
Interval 25.8 to 38.8
|
33.6 Titer
Interval 24.9 to 45.2
|
34.1 Titer
Interval 26.6 to 43.8
|
|
HAI Geometric Mean Titer
Post-vaccine: B/Victoria
|
103.8 Titer
Interval 85.7 to 125.6
|
120.4 Titer
Interval 94.3 to 153.7
|
24.4 Titer
Interval 19.3 to 31.0
|
|
HAI Geometric Mean Titer
Pre-vaccine: B/Yamagata
|
119.3 Titer
Interval 100.6 to 141.4
|
143.4 Titer
Interval 114.7 to 179.3
|
107.4 Titer
Interval 86.1 to 134.0
|
|
HAI Geometric Mean Titer
Post-vaccine: B/Yamagata
|
223.9 Titer
Interval 193.4 to 259.2
|
245.2 Titer
Interval 203.8 to 295.0
|
110.6 Titer
Interval 89.1 to 137.3
|
|
HAI Geometric Mean Titer
Post-vaccine: A(H1N1)pdm09
|
148.3 Titer
Interval 122.6 to 179.5
|
146.6 Titer
Interval 110.5 to 194.5
|
34.5 Titer
Interval 27.0 to 44.0
|
|
HAI Geometric Mean Titer
Pre-vaccine: A(H3N2)
|
20.9 Titer
Interval 17.1 to 25.4
|
22.5 Titer
Interval 16.8 to 30.0
|
21.3 Titer
Interval 16.3 to 28.0
|
|
HAI Geometric Mean Titer
Post-vaccine: A(H3N2)
|
58.5 Titer
Interval 47.0 to 72.8
|
72.0 Titer
Interval 54.6 to 94.8
|
21.7 Titer
Interval 16.6 to 28.4
|
|
HAI Geometric Mean Titer
Pre-vaccine: B/Victoria
|
24.9 Titer
Interval 20.6 to 30.0
|
29.3 Titer
Interval 22.9 to 37.7
|
22.0 Titer
Interval 17.2 to 28.3
|
PRIMARY outcome
Timeframe: Visit 1 (day 1; baseline) to Visit 2 (days 28-42; post-vaccination) for all arms/groupsPopulation: Influenza Immunogenicity Population: Subset of the mITT Population that includes only subjects who received both vaccines, provide visit 1 and visit 2 blood draws available with HAI titer results for analysis within the protocol-defined time frame, did not have an influenza or SARS-CoV-2 infection between visits 1 and 2, and had no protocol violations affecting immunogenicity.
GMFRs and 95% confidence intervals were calculated using a t-distribution on log 2-transformed titers.
Outcome measures
| Measure |
Group i
n=197 Participants
Simultaneous Vaccination (Influenza vaccine and mRNA COVID booster) at Visit 1
Simultaneous Vaccination (Influenza Vaccine and mRNA COVID booster): Influenza vaccination and mRNA COVID-19 booster will be given at Visit 1.
|
Group ii
n=95 Participants
Sequential vaccination with Influenza vaccination at Visit 1 and mRNA COVID booster at Visit 2
Sequential Vaccination (Influenza vaccine then mRNA COVID booster): Influenza vaccine will be given at Visit 1 and mRNA COVID booster will be given at Visit 2.
|
Group Iii
n=107 Participants
Sequential vaccination with mRNA COVID booster at Visit 1 and Influenza vaccination at Visit 2
Sequential Vaccination (mRNA COVID booster then Influenza vaccine): mRNA COVID booster will be given at Visit 1 and Influenza vaccine will be given at Visit 2.
|
|---|---|---|---|
|
HAI Geometric Mean Fold Rise (GMFR)
A(H1N1)pdm09
|
4.7 Fold Change
Interval 3.8 to 5.8
|
4.4 Fold Change
Interval 3.3 to 5.7
|
1.0 Fold Change
Interval 0.9 to 1.1
|
|
HAI Geometric Mean Fold Rise (GMFR)
A(H3N2)
|
2.8 Fold Change
Interval 2.3 to 3.4
|
3.2 Fold Change
Interval 2.5 to 4.2
|
1.0 Fold Change
Interval 0.9 to 1.1
|
|
HAI Geometric Mean Fold Rise (GMFR)
B/Victoria
|
4.2 Fold Change
Interval 3.5 to 5.0
|
4.1 Fold Change
Interval 3.2 to 5.3
|
1.1 Fold Change
Interval 1.0 to 1.2
|
|
HAI Geometric Mean Fold Rise (GMFR)
B/Yamagata
|
1.9 Fold Change
Interval 1.7 to 2.1
|
1.7 Fold Change
Interval 1.5 to 2.0
|
1.0 Fold Change
Interval 0.9 to 1.1
|
Adverse Events
Group i: Concomitant
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Group ii: Influenza Visit 1
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Group Iii: mRNA COVID-19 Visit 1
Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place