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 (DANFLU-1)

Tor Biering-Sørensen

Status and phase: Completed; Phase 2

Conditions: Influenza

Treatments: Drug: Standard-Dose Quadrivalent Influenza Vaccine; Drug: High-Dose Quadrivalent Influenza Vaccine

Study type: Interventional

Funder types: Other; Industry

Identifiers

NCT05048589

DANFLU-1

2021-003170-31 (EudraCT Number)

QHD00027

Details and patient eligibility

About

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.

Full 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.

Enrollment: 12,551 patients

Sex: All

Ages: 65 to 79 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

1. Age 65-79 years
2. Informed consent form has been signed and dated

Exclusion criteria

1. Allergy/hypersensitivity towards the influenza vaccines used in this study

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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12,551 participants in 2 patient groups

Standard-Dose Quadrivalent Influenza Vaccine

Active Comparator group

Description:

QIV-SD single injection at Day 0

Treatment:

Drug: Standard-Dose Quadrivalent Influenza Vaccine

High-Dose Quadrivalent Influenza Vaccine

Experimental group

Description:

QIV-HD single injection at Day 0

Treatment:

Drug: High-Dose Quadrivalent Influenza Vaccine