NCT05048589

Feasibility of Randomizing Danish Citizens Aged 65-79 Years to High-Dose Quadrivalent Influenza Vaccine vs. Standard-Dose Quadrivalent Influenza Vaccine in a Pragmatic Registry-Based Setting

• Status: Completed
• Phase: Phase 2
• Study type: Interventional
• Enrollment: 12,551 (actual)
• Sponsor: Tor Biering-Sørensen · Academic / Other
• Sex: All
• Age: 65 Years – 79 Years
• Healthy volunteers: Accepted

Summary

The purpose of the study is to assess the feasibility of identifying, recruiting and randomizing a large sample of Danish citizens aged 65-79 years to high-dose quadrivalent influenza vaccine or standard-dose quadrivalent influenza vaccine in the 2021/2022 influenza season in a registry-based setting using Danish nationwide registries for all data collection including baseline information and outcome assessment.

Detailed description

To evaluate the feasibility of recruiting and randomizing Danish citizens aged 65-79 years, we aim to randomize 40,000 citizens 1:1 to high-dose quadrivalent influenza vaccine or standard-dose quadrivalent influenza vaccine in a pragmatic, open-label, registry-based design using the infrastructure of Danske Lægers Vaccinations Service (DLVS), an organization responsible for numerous vaccination clinics in Denmark, for recruitment and randomization and Danish nationwide registries for data collection. Citizens will be recruited by DLVS and randomized and vaccinated at the DLVS clinics. All collection of data related to baseline information, outcomes, and safety monitoring will be performed by a central trial site utilizing information from Danish nationwide health registries. The findings of this pilot trial will indicate whether the conduction of a full-scale, adequately powered pragmatic RCT is feasible within the Danish registry-based framework.

Conditions

• Influenza

Interventions

Type	Name	Description
DRUG	Standard-Dose Quadrivalent Influenza Vaccine	For the control arm, the standard-dose quadrivalent influenza vaccines Influvactetra® and Vaxigriptetra will be used.
DRUG	High-Dose Quadrivalent Influenza Vaccine	For the control arm, the high-dose quadrivalent influenza vaccine Efluelda®/Fluzone® High-Dose Quadrivalent will be used.

Timeline

• Start date: 2021-10-01
• Primary completion: 2022-05-31
• Completion: 2022-05-31
• First posted: 2021-09-17
• Last updated: 2022-08-23

Locations

2 sites across 1 country: Denmark