Efficacy and safety of a quadrivalent influenza vaccine in children aged 6–35 months: A global, multiseasonal, controlled, randomized Phase III study
Vaccine·
- DOI
- 10.1016/j.vaccine.2022.02.088
- PMID
- 35315323
- PMCID
- —
- OpenAlex
- W4220948596
- Study type
- Randomised controlled trial
- Publisher
- Elsevier BV
- Article type
- journal-article
- Integrity
- current
Why this research matters now
Children under 3 years represent an important target group for influenza vaccination, yet few prospective efficacy studies exist for this age group. This trial demonstrates that primary vaccination with quadrivalent influenza vaccine is well tolerated and effective in protecting young children against influenza.
Structured evidence summary
Research question
This Phase III randomized controlled trial evaluated the efficacy, immunogenicity, and safety of an inactivated quadrivalent influenza vaccine in children aged 6–35 months.
Study design
Influenza-naïve children aged 6–35 months were randomized across three influenza seasons to receive either quadrivalent influenza vaccine or a non-influenza control vaccine, with one group revaccinated in a subsequent season. The primary endpoint was absolute vaccine efficacy against influenza caused by any circulating strain.
Population and setting
The trial enrolled 2000 influenza-naïve children aged 6–35 months, with 1005 receiving quadrivalent influenza vaccine and 995 receiving control vaccine. The study was conducted globally across multiple influenza seasons.
Main findings
Absolute vaccine efficacy against any circulating influenza strain was 54% (95% CI: 37%, 66%), rising to 68% (95% CI: 45%, 81%) against antigenically matching strains. Hemagglutination inhibition titers increased post-vaccination and remained elevated approximately 12 months after primary vaccination. Revaccination elicited strong antibody responses, and the safety profile was comparable to control vaccine.
Public-health relevance
Children under 3 years represent an important target group for influenza vaccination, yet few prospective efficacy studies exist for this age group. This trial demonstrates that primary vaccination with quadrivalent influenza vaccine is well tolerated and effective in protecting young children against influenza.
Important limitations
This summary is limited to the supplied single-article abstract and metadata and requires the original paper for decision-grade interpretation.
GIDS interpretation
This article is classified under Influenza and tagged for Treatment, Vaccination, and Vaccine effectiveness topics, making it discoverable in searches for influenza vaccine trials and immunization evidence in young children. The peer-reviewed randomized controlled trial design and current integrity status indicate methodological rigor suitable for evidence synthesis.
Related GIDS surveillance
Literature context does not validate, explain, or change a surveillance signal. Exact and contextual relationships are shown separately.
Evidence relationships
This article has 10 auditable classifier relationships to diseases, places, topics, and study design.