Effectiveness of An Influenza/COVID-19 Vaccine (mCombriax [mRNA-1083]) in Adults ≥ 65 Years
DAN-COMBO
A Phase 4, Pragmatic, Randomized Trial to Evaluate the Effectiveness of An Influenza/COVID-19 Vaccine (mCombriax [mRNA-1083]) in Adults ≥ 65 Years
2 other identifiers
interventional
410,000
2 countries
3
Brief Summary
The purpose of this pragmatic randomized trials is to evaluate the comparative vaccine effectiveness (cVE) of mCombriax® (mRNA-1083) versus same day co-administration of the active comparators (i.e., high-dose influenza vaccine/Efluelda® and mRNA-1273/Spikevax®) among adults aged 65 years and older.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for phase_4 covid19
Started Sep 2026
Longer than P75 for phase_4 covid19
3 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
Click on a node to explore related trials.
Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
August 21, 2026
CompletedFirst Posted
Study publicly available on registry
August 27, 2026
CompletedStudy Start
First participant enrolled
September 1, 2026
ExpectedPrimary Completion
Last participant's last visit for primary outcome
May 31, 2028
Study Completion
Last participant's last visit for all outcomes
September 30, 2028
August 27, 2026
August 1, 2026
1.7 years
August 21, 2026
August 25, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (2)
Medically attended influenza and/or COVID-19
Defined as a laboratory-confirmed positive influenza A/B test or positive SARS-CoV-2 test, regardless of healthcare setting, or influenza-related or COVID-19-related hospitalization, defined by ICD-10 codes.
From Day 14 after vaccination through the end of follow-up, up to 8 months after vaccination
Influenza and/or COVID-19 hospitalization
Defined as hospitalization with a relevant ICD-10 code for influenza or COVID-19 infection or any hospitalization with a laboratory-confirmed positive influenza A/B test or SARS-CoV-2 test performed within 7 days prior to hospitalization or within 48 hours of hospital admission.
From Day 14 after vaccination through the end of follow-up, up to 8 months after vaccination
Secondary Outcomes (7)
Medically attended influenza
From Day 14 after vaccination through the end of follow-up, up to 8 months after vaccination
Influenza hospitalization
From Day 14 after vaccination through the end of follow-up, up to 8 months after vaccination
Medically attended COVID-19
From Day 14 after vaccination through the end of follow-up, up to 8 months after vaccination
COVID-19 hospitalization
From Day 14 after vaccination through the end of follow-up, up to 8 months after vaccination
All-cause cardio-respiratory hospitalization
From Day 14 after vaccination through the end of follow-up, up to 8 months after vaccination
- +2 more secondary outcomes
Other Outcomes (19)
Influenza-related cardio-respiratory hospitalization
From Day 14 after vaccination through the end of follow-up, up to 8 months after vaccination
COVID-19-related cardio-respiratory hospitalization
From Day 14 after vaccination through the end of follow-up, up to 8 months after vaccination
Influenza-related respiratory tract disease hospitalization
From Day 14 after vaccination through the end of follow-up, up to 8 months after vaccination
- +16 more other outcomes
Study Arms (2)
mCombriax® (mRNA-1083)
EXPERIMENTALAn authorized mRNA-based multicomponent vaccine encoding antigens targeting both seasonal influenza and SARS-CoV-2 viruses.
Efluelda® (TIV-HD) and Spikevax® (mRNA-1273)
ACTIVE COMPARATORSame-day co-administration of an authorized high-dose trivalent influenza vaccine (TIV-HD; Efluelda®) and an authorized COVID-19 mRNA vaccine (Spikevax®, mRNA-1273)
Interventions
An authorized mRNA-based multicomponent vaccine encoding antigens targeting both seasonal influenza and SARS-CoV-2 viruses.
Same-day co-administration of an authorized high-dose trivalent influenza vaccine (TIV-HD; Efluelda®) and an authorized COVID-19 mRNA vaccine (Spikevax®, mRNA-1273)
Eligibility Criteria
You may qualify if:
- Age ≥65 years at the time of vaccination
- Self-reported ability to understand written and spoken English or Danish (Denmark only) or Spanish or Galician (Spain only)
- Informed consent form has been signed and dated
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Tor Biering-Sørensenlead
- ModernaTX, Inc.collaborator
Study Sites (3)
Center for Translational Cardiology and Pragmatic Randomized Trials, Department of Cardiology, Copenhagen University Hospital - Herlev and Gentofte
Hellerup, 2900, Denmark
Danske Lægers Vaccinations Service
Søborg, 2860, Denmark
General Public Health Directorate of Galician Health Service
Santiago de Compostela, A Coruña, Spain
MeSH Terms
Conditions
Interventions
Condition Hierarchy (Ancestors)
Intervention Hierarchy (Ancestors)
Study Officials
- STUDY CHAIR
Tor Biering-Sørensen
Center for Translational Cardiology and Pragmatic Randomized Trials, Department of Cardiology, Copenhagen University Hospital - Herlev and Gentofte
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- phase 4
- Allocation
- RANDOMIZED
- Masking
- NONE
- Purpose
- PREVENTION
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- SPONSOR INVESTIGATOR
- PI Title
- Professor, MD, MSc, MPH, PhD
Study Record Dates
First Submitted
August 21, 2026
First Posted
August 27, 2026
Study Start (Estimated)
September 1, 2026
Primary Completion (Estimated)
May 31, 2028
Study Completion (Estimated)
September 30, 2028
Last Updated
August 27, 2026
Record last verified: 2026-08
Data Sharing
- IPD Sharing
- Will share
- Shared Documents
- STUDY PROTOCOL, SAP
In this trial, baseline and endpoint data will be collected from Danish administrative health registries, which are subject to Danish legislation and can only be made available to a third party under certain conditions. Please contact the sponsor-investigator in case of any inquiries.