Trial Outcomes & Findings for Revealing Protective Immunity to Influenza Using Systems Immunology (NCT NCT06501963)
NCT ID: NCT06501963
Last Updated: 2026-03-30
Results Overview
The immunogenicity of the live attenuated influenza vaccine (LAIV) is evaluated by the quantification of antibody titers using hemagglutination inhibition (HAI) assays. HAI titers are used as markers of part of the immune response to influenza and may vary by influenza strain.
COMPLETED
PHASE4
51 participants
Day 30
2026-03-30
Participant Flow
Participants were recruited from The Hope Clinic of the Emory Vaccine Center in Atlanta, Georgia, USA. Participant enrollment began October 14, 2024 and all follow-up assessments were completed by April 1, 2025.
Participant milestones
| Measure |
Live Attenuated Influenza Vaccine
Participants receiving a single dose of the live attenuated influenza vaccine (LAIV).
The FDA-approved live attenuated seasonal influenza vaccine (LAIV) (FluMist®, AstraZeneca) is licensed in the US for people 2-49 years of age. The approved seasonal LAIV at the time of study enrollment will be obtained from the manufacturer. LAIV will be administered by a study nurse or health care provider at the Hope Clinic as a single 0.2 milliliter (mL) dose given as 0.1 mL spray in each nostril.
|
|---|---|
|
Overall Study
STARTED
|
51
|
|
Overall Study
COMPLETED
|
47
|
|
Overall Study
NOT COMPLETED
|
4
|
Reasons for withdrawal
| Measure |
Live Attenuated Influenza Vaccine
Participants receiving a single dose of the live attenuated influenza vaccine (LAIV).
The FDA-approved live attenuated seasonal influenza vaccine (LAIV) (FluMist®, AstraZeneca) is licensed in the US for people 2-49 years of age. The approved seasonal LAIV at the time of study enrollment will be obtained from the manufacturer. LAIV will be administered by a study nurse or health care provider at the Hope Clinic as a single 0.2 milliliter (mL) dose given as 0.1 mL spray in each nostril.
|
|---|---|
|
Overall Study
Lost to Follow-up
|
2
|
|
Overall Study
Withdrawal by Subject
|
2
|
Baseline Characteristics
Revealing Protective Immunity to Influenza Using Systems Immunology
Baseline characteristics by cohort
| Measure |
Live Attenuated Influenza Vaccine
n=51 Participants
Participants receiving a single dose of the live attenuated influenza vaccine (LAIV).
|
|---|---|
|
Age, Categorical
<=18 years
|
0 Participants
n=4 Participants
|
|
Age, Categorical
Between 18 and 65 years
|
51 Participants
n=4 Participants
|
|
Age, Categorical
>=65 years
|
0 Participants
n=4 Participants
|
|
Age, Continuous
|
33.8 years
STANDARD_DEVIATION 8.4 • n=4 Participants
|
|
Sex: Female, Male
Female
|
34 Participants
n=4 Participants
|
|
Sex: Female, Male
Male
|
17 Participants
n=4 Participants
|
|
Ethnicity (NIH/OMB)
Hispanic or Latino
|
6 Participants
n=4 Participants
|
|
Ethnicity (NIH/OMB)
Not Hispanic or Latino
|
45 Participants
n=4 Participants
|
|
Ethnicity (NIH/OMB)
Unknown or Not Reported
|
0 Participants
n=4 Participants
|
|
Race (NIH/OMB)
American Indian or Alaska Native
|
1 Participants
n=4 Participants
|
|
Race (NIH/OMB)
Asian
|
6 Participants
n=4 Participants
|
|
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
|
0 Participants
n=4 Participants
|
|
Race (NIH/OMB)
Black or African American
|
20 Participants
n=4 Participants
|
|
Race (NIH/OMB)
White
|
20 Participants
n=4 Participants
|
|
Race (NIH/OMB)
More than one race
|
2 Participants
n=4 Participants
|
|
Race (NIH/OMB)
Unknown or Not Reported
|
2 Participants
n=4 Participants
|
|
Region of Enrollment
United States
|
51 Participants
n=4 Participants
|
PRIMARY outcome
Timeframe: Day 30Population: This analysis includes participants who completed the study.
The immunogenicity of the live attenuated influenza vaccine (LAIV) is evaluated by the quantification of antibody titers using hemagglutination inhibition (HAI) assays. HAI titers are used as markers of part of the immune response to influenza and may vary by influenza strain.
Outcome measures
| Measure |
Live Attenuated Influenza Vaccine
n=47 Participants
Participants receiving a single dose of the live attenuated influenza vaccine (LAIV).
|
|---|---|
|
Quantification of Antibody Titers
H1N1
|
37.4 Antibody titer
Standard Deviation 1.79
|
|
Quantification of Antibody Titers
H3N2
|
24.6 Antibody titer
Standard Deviation 1.51
|
|
Quantification of Antibody Titers
B/Victoria
|
6.81 Antibody titer
Standard Deviation 0.83
|
SECONDARY outcome
Timeframe: Day 30Population: This analysis includes participants who completed the study.
The effect of LAIV on eliciting influenza-specific immune responses is analyzed as the geometric mean fold rise (GMFR) in hemagglutination inhibition (HAI) titers. The GMFR indicates a change in antibody titer after immunization.
Outcome measures
| Measure |
Live Attenuated Influenza Vaccine
n=47 Participants
Participants receiving a single dose of the live attenuated influenza vaccine (LAIV).
|
|---|---|
|
Geometric Mean Fold Rise in HAI Titers
Geometric Mean Fold Rise of H1N1
|
1.04 Ratio of antibody titers
Standard Deviation 0.92
|
|
Geometric Mean Fold Rise in HAI Titers
Geometric Mean Fold Rise of H3N2
|
1.49 Ratio of antibody titers
Standard Deviation 0.95
|
|
Geometric Mean Fold Rise in HAI Titers
Geometric Mean Fold Rise of B/Victoria
|
1.09 Ratio of antibody titers
Standard Deviation 0.40
|
SECONDARY outcome
Timeframe: Up to Day 30The safety profile of LAIV is assessed as the frequency of serious adverse events occurring up to 30 days after vaccination.
Outcome measures
| Measure |
Live Attenuated Influenza Vaccine
n=51 Participants
Participants receiving a single dose of the live attenuated influenza vaccine (LAIV).
|
|---|---|
|
Number of Serious Adverse Events
|
0 serious adverse events
|
Adverse Events
Live Attenuated Influenza Vaccine
Serious adverse events
Adverse event data not reported
Other adverse events
| Measure |
Live Attenuated Influenza Vaccine
n=51 participants at risk
Participants receiving a single dose of the live attenuated influenza vaccine (LAIV).
|
|---|---|
|
Skin and subcutaneous tissue disorders
Hives
|
2.0%
1/51 • Information on adverse events was collected beginning at the vaccination visit (Day 0) through the final follow-up assessment at Day 30 (up to 30 days).
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Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place