Can a new vaccine shield us from bird flu?

NCT ID NCT07779408

What the study statuses mean

This study's is highlighted.

Recruitment status, easiest to join first

Recruiting now
This trial is taking on new participants right now.
Not yet recruiting This study
Registered, but not yet taking participants.
By invitation only
Not open to general applications. Only people the study team invites can take part.
Paused
Paused for now. It may or may not start again.
Ongoing
Running, but no longer taking on new participants.
Completed
The trial has finished. Results may not be published yet.
Stopped early
Stopped early, before it reached the end. That can be for many reasons, including safety.
Cancelled
Cancelled before anyone took part.

Expanded access (not trials)

Expanded access
Not a trial. This treatment can be requested outside a study, case by case, for people who qualify.
Expanded access (paused)
Not a trial. The treatment can normally be requested outside a study, but is unavailable right now.
Expanded access (ended)
Not a trial. The treatment could once be requested outside a study, but no longer can.
Approved
The treatment has been approved, so it is available normally rather than through this programme.

When the status isn't known

Details not published
The full record has not been published yet, so there is little to show here.
Status unknown
This status has not been confirmed recently, so it may be out of date.

First seen Aug 21, 2026 · Last updated Aug 21, 2026

Summary

This trial is testing an experimental vaccine against H5N8, a type of bird flu, in healthy adults aged 18 and older. The vaccine is made using eggs and is given as two shots, with or without an adjuvant—a substance that may boost the immune response. The study aims to see if the vaccine is safe and how well it triggers the body's defenses against the virus. Participants will be monitored for about 14 months to track side effects and antibody levels.

What this could mean

Our plain-language read of the trial. This is informational only, not medical advice or a prediction.

Active substance
An experimental egg-based H5N8 influenza vaccine, given with or without an adjuvant (Matrix-M) to boost immune response.
What this could lead to
If successful, this could help develop a vaccine to protect against future H5N8 flu outbreaks, potentially reducing pandemic risk.
What could go wrong
This is an early-stage trial, so the vaccine may not produce a strong enough immune response or may cause side effects. Results from this small study may not predict real-world effectiveness.

This is an AI summary of the original study and may miss details. Read our disclaimer.

Study facts

What this study's own registry entry says, in plain language.

Phase

Phase 1/2

Runs two stages together: safety and dose first, then whether the treatment works.

Participants

About 640 people

The number the study aims to enrol. It can still change while the study runs.

Expected to start

Aug 2026

An estimate. Start dates often move.

Expected to finish

Feb 2028

An estimate. End dates often move.

Lead sponsor

A company

The lead sponsor is a pharmaceutical, biotech, or medical-device company.

Who can take part

This study's own entry requirements. Only the study team can say for certain whether you qualify.

Ages

18 years and older

Sex

Anyone

Healthy volunteers

Accepted

You do not need to have the condition being studied to take part.

Show the full entry requirements

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Aged 18 years or above on the day of inclusion * Participants who are healthy as determined by medical evaluation including medical history * Not pregnant/breastfeeding; non-childbearing potential or uses effective contraception/abstinence from ≥4 weeks before the first study intervention dose to ≥8 weeks after the last dose * Informed consent form has been signed and dated * Able to attend all scheduled visits and to comply with all study procedures * Covered by health insurance, if required by local regulations Exclusion Criteria: * Known or suspected immunodeficiency; immunosuppressive therapy in past 6 months; or long-term systemic corticosteroid (eg, prednisone for more than 2 weeks in the past 3 months) * Known hepatitis B or hepatitis C infection (based on medical history) * Known personal or family history of previous episodes of Guillan-Barré syndrome (GBS), neuritis (including Bell's palsy), convulsions, encephalitis, transverse myelitis, and vasculitis * Known systemic hypersensitivity to any of the study intervention components or history of life-threatening reaction to the study interventions or products with same substances * Self-reported thrombocytopenia contraindicating intramuscular (IM) injection based on investigator's judgment * Bleeding disorder, or receipt of anticoagulants in the 3 weeks preceding inclusion, contraindicating IM injection based on investigator's judgment * Chronic illness that, in the opinion of the investigator, is at a stage where it might interfere with study conduct or completion * History of A/H5 infection prior to the study participation * Moderate or severe acute illness/infection (per investigator judgment)/fever (≥ 38.0°C \[≥ 100.4°F\]) on study intervention day. Include participant only after the condition or fever has resolved * Alcohol, prescription drug, or substance abuse that, in the opinion of the investigator, might interfere with the study conduct or completion * Any vaccine given 4 weeks before first study intervention or any planned vaccination to be given prior to Day 43 (ie, approximately 21 days after the second study intervention) * Previous vaccination against A(H5) with an investigational or marketed vaccine. This includes, but is not limited to, influenza subtypes A(H5N1), A(H5N8), and A(H5N6) * Has received a blood transfusion or blood-derived products, including immunoglobulins in the past 3 months * Participation in another clinical study for a vaccine, drug, medical device, or medical procedure within 4 weeks before enrollment or planned participation during the present study period * Deprived of freedom by an administrative or court order, or in an emergency setting, or hospitalized involuntarily * Is an investigator, investigator/study center employee, or immediate family member (parent, spouse, natural/adopted child) of the investigator/employee with direct involvement in the study * Any screening safety laboratory parameters out of normal ranges and assessed as \> Grade 2 The above information is not intended to contain all considerations relevant to a participant's potential participation in a clinical trial.

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Conditions

The condition(s) this trial relates to.

As listed by the trial registrant

The condition terms exactly as the trial's registrant entered them.

How to take part

Only the study team decides who joins. These are the ways to reach them.

  1. The study's own enquiry address

    This study publishes an address for enquiries. See it below .

  2. The official record

    ClinicalTrials.gov lists the study team's own contact details, including names and phone numbers. We don't republish those.

    Open the record ↗

  3. A doctor treating you

    A doctor who knows your case can contact a study site on your behalf, and can tell you whether this study is worth pursuing at all.

Contacts and locations

Study contacts

  • Contact

    Email: •••••@•••••

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