Skip to content
Clinical Trials – home
Not recruiting

A Study Testing mRNA-1273 Vaccine Safety and Effectiveness Against Severe COVID-19 in Adults Aged 50-64 Years Without Risk Factors

Verified siteRegistered drug
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

What is this trial about?

A plain-language summary of the goals, design and what participants do

This study is looking at SARS-CoV-2 infection, which is the virus that causes COVID-19. The study will use a vaccine called Spikevax, which contains elasomeran, also known by its code name mRNA-1273. This is a messenger RNA vaccine that teaches the body to recognize and fight against the virus. The vaccine will be given as a single injection into the muscle. The study will involve adults between 50 and 64 years of age who do not have risk factors that would make COVID-19 more severe for them.

The purpose of this study is to find out how well the vaccine works in reducing the risk of COVID-19 that requires medical attention compared to not receiving the vaccine. The study will also look at how safe the vaccine is in this age group. This is a randomized trial, which means that participants will be assigned by chance to either receive the vaccine or not receive it. The researchers will then compare the two groups to see if there are differences in how many people develop COVID-19 that needs medical care.

During the study, researchers will track whether participants develop COVID-19 by looking at positive test results or hospital admissions related to the infection. They will also look at other outcomes such as hospitalizations for breathing problems related to COVID-19, heart and breathing problems, and deaths. The study will follow participants over time to collect this information and determine how effective the vaccine is in preventing illness in this specific age group without other health conditions that put them at higher risk.

The research process

The trial runs in 3 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Enrollment and vaccination

    After joining the study, you will be randomly assigned to one of two groups. One group will receive the vaccine, and the other group will not receive the vaccine at this time.

    If you are assigned to the vaccine group, you will receive Spikevax 50 micrograms vaccine. This is an mRNA vaccine that helps protect against COVID-19.

    The vaccine will be given as a single injection into your muscle, typically in your upper arm.

    The vaccine comes in a pre-filled syringe and is administered by a healthcare professional.

  2. Step 2

    Follow-up period

    After receiving the vaccine or being assigned to the non-vaccine group, you will be followed through health registries.

    The study will track whether you develop COVID-19 that requires medical attention. This is defined as either a positive PCR test (a laboratory test that detects the virus) for SARS-CoV-2 or hospitalization for COVID-19-related breathing problems.

    The study will also monitor other health outcomes, including hospitalizations related to COVID-19, breathing problems, heart and lung issues, and overall health status.

    Your participation in the follow-up period will continue until the study ends, which is estimated to be in August 2026.

  3. Step 3

    Data collection

    Information about your health will be collected from national health registries throughout the study period.

    This includes records of any COVID-19 diagnoses, hospital admissions, and other relevant health events.

    No additional visits or procedures beyond the initial vaccination are required from you during the study.

Who can join the trial?

2 criteria

  • You must be between 50 and 64 years old
  • You must sign and date an informed consent form, which is a document that explains the study and confirms you agree to take part

Who cannot join the trial?

3 criteria

  • The study does not list specific reasons why you cannot participate
  • General exclusion criteria will be determined by the study doctors during screening
  • You should discuss your medical history and current health status with the study team to find out if you can take part
Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

We usually reply within a few days

Verified sites

All sites with verified contact details – recruitment status may not be available; ask directly

Trial locations

Where you can join this trial

Countries are shaded by recruitment status. Click a recruiting country to ask about joining there.

Not recruiting
Not finding your country?

Not sure what to do next?

Joining a clinical trial can seem overwhelming. We guide you step by step, so you know exactly what to expect and how we support you through the process.

See the full process and FAQ

Investigated drugs

mRNA-1273 is a vaccine that helps protect against COVID-19. This vaccine works by teaching your body to recognize and fight the virus that causes COVID-19. In this trial, researchers are testing a version of this vaccine that has been updated to work against different variants (changed forms) of the COVID-19 virus. The vaccine is being studied to see how well it prevents COVID-19 infections that require medical attention in adults between 50 and 64 years old who do not have health conditions that put them at higher risk for severe COVID-19.

What is already known about the treatment

mRNA-1273 – This is an injectable vaccine given as a shot into the muscle, designed to protect against COVID-19 caused by the SARS-CoV-2 virus. The vaccine works by delivering genetic instructions (messenger RNA) into your cells, which then produce a harmless piece of the virus's spike protein, teaching your immune system to recognize and fight the actual virus if you encounter it later. It belongs to the class of mRNA vaccines and is an authorized medical product used to prevent COVID-19 infection and its complications. This clinical trial specifically studies how well variant-containing versions of this vaccine protect adults aged 50-64 without other health risks from developing COVID-19 that requires medical attention.

Investigated diseases

SARS-CoV-2 Infection – SARS-CoV-2 infection is a viral illness caused by the severe acute respiratory syndrome coronavirus 2. The virus primarily spreads through respiratory droplets when an infected person coughs, sneezes, or talks. After entering the body, the virus attaches to cells in the respiratory tract and begins to multiply. The infection can affect various organs, though it most commonly impacts the lungs and breathing system. Some people experience mild symptoms such as fever, cough, and fatigue, while others may develop more severe breathing difficulties. The disease can progress from initial mild symptoms to more serious respiratory problems requiring medical attention.
Trial detailsLast updated 2 Oct 2026
Age18+ yearsPhasePhase IIITrial ID2025-523841-82-00Protocol codeDAN-COVIDEstimated enrolment285 000 patientsSponsorGentofte Hospital

sourced from the EU Clinical Trials Register and site verification

Want to learn more about this trial or check if you can participate?

Clinical Trials Concierge

Prefer not to search? Our Concierge searches the trials for you.

Tell us about your condition – we search every trial in Europe and connect you with the right site.

Legal notice · Published by CTIN POLAND sp. z o.o., ul. rtm. Witolda Pileckiego 67/109, 02-781 Warsaw, Poland · KRS 0001111334 · REGON 528919042 · NIP 9512598637

© 2026 Clinical Trials EU – European Clinical Trials Information Network

GDPR compliance, ISO 9001 and ISO 27001 certified (LL-C Certification)

On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).