A Pragmatic Randomized Feasibility Trial of Influenza Vaccines.
NEJM Evid
; 2(2): EVIDoa2200206, 2023 Feb.
Article
en En
| MEDLINE
| ID: mdl-38320035
ABSTRACT
BACKGROUND:
The relative vaccine effectiveness (rVE) of high-dose quadrivalent influenza vaccines (QIV-HD) versus standard-dose quadrivalent influenza vaccines (QIV-SD) against hospitalizations and mortality in the general older population has not been evaluated in an individually randomized trial. Because of the large sample size required, such a trial will need to incorporate innovative, pragmatic elements.METHODS:
We conducted a pragmatic, open-label, active-controlled, randomized feasibility trial in Danish citizens aged 65 to 79 years during the 20212022 influenza season. Participants were randomly assigned 11 to receive QIV-HD or QIV-SD. Randomization was integrated into routine vaccination practice, and the trial relied solely on nationwide administrative health registries for data collection. Outcomes consisted of a feasibility assessment and descriptive rVE estimates.RESULTS:
We invited 34,000 persons to participate. A total of 12,477 randomly assigned participants were included in the final analyses. Mean (±SD) age was 71.7±3.9 years, and 5877 (47.1%) were women. Registry-based data collection was feasible, with complete follow-up data for 99.9% of participants. Baseline characteristics were comparable to those of the overall Danish population aged 65 to 79 years. The incidence of hospitalization for influenza or pneumonia was 10 (0.2%) of 6245 in the QIV-HD group and 28 (0.4%) of 6232 in the QIV-SD group (rVE, 64.4%; 95% confidence interval, 24.4 to 84.6). All-cause death occurred in 21 (0.3%) and 41 (0.7%) participants in the QIV-HD and QIV-SD groups, respectively (rVE, 48.9%; 95% confidence interval, 11.5 to 71.3).CONCLUSIONS:
Conducting a pragmatic randomized trial of QIV-HD versus QIV-SD using existing infrastructure and registry-based data collection was feasible. The findings of lower incidence of hospitalization for influenza or pneumonia and all-cause mortality in the QIV-HD group compared with the QIV-SD group require replication in a future, fully powered trial. (Funded by Sanofi; ClinicalTrials.gov number, NCT05048589.)
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Vacunas contra la Influenza
/
Gripe Humana
Tipo de estudio:
Clinical_trials
Límite:
Humans
Idioma:
En
Revista:
NEJM Evid
Año:
2023
Tipo del documento:
Article