Can kids get COVID and routine shots on the same day? new study says maybe.

NCT ID NCT06038617

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
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 This study
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 Results may not be published yet.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This status has not been confirmed recently, so it may be out of date.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 Jun 27, 2026 · Last updated Jun 27, 2026

Summary

This study looked at whether it's safe to give young children (6 months to 5 years old) their mRNA COVID-19 vaccine at the same time as other routine childhood vaccines. About 347 children took part, and researchers tracked fevers and other side effects for a week after vaccination. The goal was to see if combining shots causes more fevers than giving them separately.

What this could mean

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

Active substance
mRNA COVID-19 vaccine (Pfizer or Moderna) and routine childhood vaccines (e.g., MMR, DTaP, polio)
What this could lead to
If successful, this could show that giving COVID-19 shots with other routine vaccines on the same day is safe for young children, simplifying vaccination schedules.
What could go wrong
This is a completed Phase 4 safety study with 347 children, so results are available. However, it only looked at fever and short-term side effects, not long-term safety or 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 4

Runs after approval, following long-term safety and how well the treatment works in everyday use.

Participants

347 people

The number who actually took part.

Started

Oct 2023

Finished

Jul 2025

Lead sponsor

Other sponsor

The registry's catch-all category, for sponsors it does not file as a company, a government agency, or a research network.

Who can take part

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

Ages

6 months to 4 years

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: * Child 6 months through \<5 years of age at time of enrollment. * Child is due to receive mRNA COVID-19 vaccine and at least one other routinely recommended non-live vaccine per CDC or ACIP recommendations. * Parental/LAR intention of child receiving mRNA COVID-19 vaccine and at least one recommended non-live vaccine. * The parent/LAR must be willing and capable of providing permission for their child to participate through the written informed consent process. * The parent/LAR must be available for follow-up and must at minimum have telephone access. * The parent/LAR must agree to sign a medical release for the child so that study personnel may obtain medical information about the child's health (if needed). * The parent/LAR must be willing to delay COVID-19 vaccination for their child for up to 3 weeks. * The parent/LAR must be able to read English or Spanish. Exclusion Criteria: * History of any seizure (including febrile seizure) or first degree relative (biologic parent or biologic sibling including half-sibling) with a history of febrile seizure. * Contraindication to mRNA COVID-19 vaccine: A history of a severe allergic reaction (e.g., anaphylaxis) after a previous dose or to a component of the COVID-19 vaccine or a known diagnosed allergy to a component of COVID-19 vaccine. * A history of a severe allergic reaction (e.g., anaphylaxis) after a previous dose or to a component of a vaccine administered on the day of study enrollment. * For children receiving DTaP vaccine (alone or combination vaccine): Encephalopathy (e.g., coma, decreased level of consciousness, prolonged seizures), not attributable to another identifiable cause, within 7 days of administration of previous dose of DTP or DTaP. * Received any other non-live vaccines within 14 days prior to enrollment or any other live vaccines within 28 days prior to enrollment. * Intention to receive non-COVID-19 non-live or live vaccines during the 4 weeks after Visit 1; vaccines may be administered after enrollment if deemed a personal or public health priority by the health care provider caring for this patient or the study team. * Received prior COVID-19 vaccine as part of a clinical trial. * Received any experimental/investigational agent (vaccine, drug, biologic, device, blood product, or medication) within 28 days prior to enrollment in this study or expects to receive an experimental/investigational agent during the study. * A moderate to severe acute illness and/or a reported temperature ≥ 100.4°F (≥38.0°C) within 48 hours prior to enrollment or a temperature (measured by temporal artery thermometer) ≥100.4°F (≥38.0°C) at the time of enrollment. (This may result in a temporary delay of vaccination). * Receipt of an antipyretic medication (acetaminophen or ibuprofen) within 72 hours prior to enrollment (this may result in a temporary delay of vaccination) or planned receipt of a prophylactic antipyretic medication on the day of and/or days following vaccination prior to any measured increase in temperature in anticipation of a fever (this exclusion does not apply if the Parent/LAR indicates they might administer antipyretics or analgesics after vaccination to reduce a fever or pain). * Immunosuppression as a result of an underlying illness or treatment, or use of anti-cancer chemotherapy or radiation therapy since birth. * Long term (at least 14 days of prednisone 2 mg/kg/day or equivalent other glucocorticoid) use of any parenteral steroids or high-dose inhaled steroids (\>800 mcg/day of beclomethasone dipropionate or equivalent) within the 6 months prior to enrollment (topical and nasal steroids are allowed). * Has an active case of COVID-19 infection. * History of multisystem inflammatory syndrome (MIS-C). * History of myocarditis or pericarditis. * Has any condition that would, in the opinion of the site investigator, place the participant at an unacceptable risk of injury or render the participant unable to meet the requirements of the protocol. * Any child or grandchild of a study investigator or study team member.

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Conditions

The condition(s) this trial relates to.

Fever Seizures, Febrile

As listed by the trial registrant

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

Contacts and locations

Locations

  • Centers for Disease Control and Prevention

    Atlanta, Georgia, 30333, United States

  • Cincinnati Children's Hospital Medical Center

    Cincinnati, Ohio, 45229, United States

  • Columbia University

    New York, New York, 10027, United States

  • Duke University

    Durham, North Carolina, 27710, United States

  • Kaiser Permanente Northern California

    Oakland, California, 94612, United States

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