National Cohort Study of Effectiveness and Safety of SARS-CoV-2/COVID-19 Vaccines (ENFORCE) (ENFORCE)
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ClinicalTrials.gov Identifier: NCT04760132 |
Recruitment Status :
Recruiting
First Posted : February 18, 2021
Last Update Posted : April 12, 2022
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National cohort study of effectiveness and safety of SARS-CoV-2 vaccines (ENFORCE is an equivalence trial to evaluate the effectiveness and safety of multiple new SARS-CoV-2 vaccines approved for use in the EU, and which are being offered at participating units.
The design is an open-labelled, non-randomised, parallel group, phase IV study with historical controls.
A sub-study will be embedded within this master protocol addressing basic and translational research questions requiring additional sampling of biological material (under separate participant informed consent).
Condition or disease | Intervention/treatment | Phase |
---|---|---|
SARS-CoV Infection | Biological: COMIRNATY - BioNTech Manufacturing GmbH Biological: COVID-19 Vaccine Moderna dispersion for injection - MODERNA BIOTECH Biological: COVID-19 Vaccine AstraZeneca suspension for injection | Phase 4 |
First phase will enrol 10,000 persons initiating vaccination (assuming 4 vaccines). If more vaccines become available additional 2,500 persons per vaccine will be included. Subsequent phases with larger sections of the population included may be implemented.
Participants will have 6 study visits and be followed for 2 years after the first vaccination, which offers the participants an extra close follow up on vaccine effectiveness. Safety data will be collected at study visits until 3 months after the first vaccination. Research samples will be collected at each study visit during the two year follow-up
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 10000 participants |
Allocation: | Non-Randomized |
Intervention Model: | Parallel Assignment |
Intervention Model Description: | The design is an open-labelled, non-randomised, parallel group, phase IV study with historical controls. |
Masking: | None (Open Label) |
Primary Purpose: | Other |
Official Title: | National Cohort Study of Effectiveness and Safety of SARS-CoV-2/COVID-19 Vaccines |
Actual Study Start Date : | February 8, 2021 |
Estimated Primary Completion Date : | December 31, 2024 |
Estimated Study Completion Date : | December 31, 2024 |

Arm | Intervention/treatment |
---|---|
Active Comparator: Vaccine A - COMIRNATY COVID-19 vaccine
COMIRNATY (COVID-19, mRNA Vaccine) by BioNTech Manufacturing GmbH Marketing Authorisation EU/1/20/1528
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Biological: COMIRNATY - BioNTech Manufacturing GmbH
Vaccination as part of the the Danish national government programme |
Active Comparator: Vaccine B - Moderna COVID-19 vaccine
COVID-19 Vaccine Moderna dispersion for injection (COVID-19, mRNA Vaccine) by MODERNA BIOTECH SPAIN S.L. Marketing Authorisation EU/1/20/1507/001 |
Biological: COVID-19 Vaccine Moderna dispersion for injection - MODERNA BIOTECH
Vaccination as part of the the Danish national government programme |
Active Comparator: Vaccine C - Astra-Zeneca COVID-19 vaccine
COVID-19 Vaccine AstraZeneca suspension for injection (ChAdOx1-S [recombinant]) by AstraZeneca AB Marketing Authorisation EU/1/21/1529/001 and /002
|
Biological: COVID-19 Vaccine AstraZeneca suspension for injection
Vaccination as part of the the Danish national government programme |
- Assessment of the effectiveness of citizens being vaccinated with one of the SARS-CoV-2 vaccines [ Time Frame: The change from Base-line in MPNAT measured via profiling of antibodies against SARS-CoV-2 Spike epitopes at 24 month ]Primary outcome is the minimal protective neutralising antibody titre (MPNAT); i.e. the minimum level of neutralising antibodies sufficient to protect the person from becoming infected.
- Number of breakthrough infections in the 24 months period will be used to compare the effectiveness between the vaccines [ Time Frame: The change from first vaccination until 24 month ]Number of confirmed positive SARS-CoV-2 tests reported via the national testing system.
- Assessment of the safety of the vaccines will be compared between groups [ Time Frame: From first vaccine until Day 90 ]Reports of participants with local and systemic reactions to the vaccination will be collected
- Assessment of any Adverse Event from the vaccines will be compared between groups [ Time Frame: From first vaccine until Day 90 ]Reports of participants with grade 3 and 4 Adverse Events and any Serious Adverse will be collected

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | Yes |
Inclusion Criteria:
- Written informed consent obtained before any trial related procedures are performed
- Male or female eligible for SARS-CoV-2 immunization (as defined by SST in the national vaccination plan)
- The subject must be willing and able to comply with trial protocol (re-visits and biological samples)
Exclusion Criteria:
- Male and female under the age of 18
- Any subgroup of individuals for which the vaccines are contraindicated
- Previous SARS-CoV-2 vaccination

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04760132
Contact: Dorthe Raben | +45 3545 5757 | dorthe.raben@regionh.dk | |
Contact: Charlotte B Nielsen | +45 3545 5757 | charlotte.bjernved.nielsen.01@regionh.dk |
Denmark | |
Aarhus Universitetshospital, Skejby | Recruiting |
Aarhus, Aarhus N, Denmark, 8200 | |
Contact: Lars Østergaard, Professor +45 7845 2800 Larsoest@rm.dk | |
Contact: Nina B Stærke, MD NINASE@rm.dk | |
Aalborg Universityhospital Syd | Recruiting |
Aalborg, Denmark, 9000 | |
Contact: Henrik Nielsen, MD +45 9766 3900 henrik.nielsen@rn.dk | |
Hvidovre Hospital | Recruiting |
Hvidovre, Denmark, 2600 | |
Contact: Thomas L Benfield, Professor +45 3862 2302 thomas.lars.benfield@regionh.dk | |
Odense Universityhospital | Recruiting |
Odense, Denmark, 5000 | |
Contact: Isik S Johansen, Professor 45 6541 2652 isik.somuncu.johansen@rsyd.dk | |
Sjællandsuniversitetshospital | Recruiting |
Roskilde, Denmark, 4000 | |
Contact: Lothar Wiese, MD +45 4532 3200 low@regionsjaelland.dk |
Study Chair: | Jens Lundgren, Professor | Rigshospitalet, Denmark |
Responsible Party: | Jens D Lundgren, MD, Professor, Rigshospitalet, Denmark |
ClinicalTrials.gov Identifier: | NCT04760132 |
Other Study ID Numbers: |
ENFORCE |
First Posted: | February 18, 2021 Key Record Dates |
Last Update Posted: | April 12, 2022 |
Last Verified: | April 2022 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | No |
Studies a U.S. FDA-regulated Device Product: | No |
COVID-19 Vaccination |
COVID-19 Severe Acute Respiratory Syndrome Pneumonia, Viral Pneumonia Respiratory Tract Infections Infections Virus Diseases Coronavirus Infections |
Coronaviridae Infections Nidovirales Infections RNA Virus Infections Lung Diseases Respiratory Tract Diseases Vaccines Immunologic Factors Physiological Effects of Drugs |