A Phase 4 interventional study of Respiratory Syncytial Virus (RSV) Preventive Monoclonal Antibody in Fever and Adverse Event Following Immunisation, sponsored by Duke University. Recruiting at 6 sites in United States. Open to participants aged 6 Weeks to 30 Weeks, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-03-16.
Sponsored by Duke University · Phase 4, Interventional, and Prevention
This is a prospective, randomized, open-label clinical trial to evaluate the safety of administration of respiratory syncytial virus (RSV) preventive monoclonal antibody and other routine childhood vaccines given simultaneously at Visit 1, as compared to sequential administration of respiratory syncytial virus (RSV) preventive monoclonal antibody and other vaccines at separate visits (Visits 1 and 2).
Parent(s) or legal guardians will assess fever and other solicited local and systemic adverse events on the day of immunization (Day 1) and the next 6 days (through Day 7) following Visit 1 and Visit 2 using either a web-based data collection system or a paper memory aid. Serious adverse events and adverse events of special interest will be captured during the entire study period.
438 studies on the registry are indexed under Fever; 55 are open to participants now.
This study's planned enrollment of 524 is above the median of 123 across 271 interventional studies indexed under Fever.
Browse Fever studies →Duke University is the lead sponsor of 2,063 studies on the registry; 273 are open to participants now.
Of its 204 completed or terminated interventional studies of FDA-regulated products, 167 (82%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Live vaccines
Vaccines made with a weakened form of the germ, such as measles–mumps–rubella (MMR), chickenpox and yellow fever. They can be risky when the immune system is weakened. Flu injections are not live; the nasal flu spray is.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The simultaneous immunization group will receive routine childhood vaccinations and respiratory syncytial virus (RSV) preventive monoclonal antibody at Visit 1.
Drug: Respiratory Syncytial Virus (RSV) Preventive Monoclonal Antibody
The sequential immunization group will receive routine childhood vaccinations at Visit 1, followed by respiratory syncytial virus (RSV) preventive monoclonal antibody at Visit 2.
Drug: Respiratory Syncytial Virus (RSV) Preventive Monoclonal Antibody
ACIP Recommended Preventive Monoclonal Antibody
Also known as: Nirsevimab, Beyfortus
Number of Participants with Fever Following Immunization
Number of infants with fever (temperature ≥ 38.0°C or ≥ 100.4°F) on day 1 and/or day 2 following Visit 1 and/or Visit 2.
Time frame: Up to 2 days post administration
Number of Participants with Grade 2 and/or 3 Fever Following Visit 1
Number of infants with moderate/severe fever (Grade 2 and/or 3) on day 1 and/or day 2 following Visit 1. (Moderate/severe fever: ≥ 38.4°C or ≥ 101.2°F)
Time frame: Up to 2 days post administration
Number of Participants with Grade 2 and/or 3 Fever Following Visit 2
Number of infants with moderate/severe fever (Grade 2 and/or 3) on day 1 and/or day 2 following Visit 2. (Moderate/severe fever: ≥ 38.4°C or ≥ 101.2°F)
Time frame: Up to 2 days post administration
The Number of Participants with At Least One Serious Adverse Event
Time frame: Up to 98 days post administration
The Number of Participants with At Least One Adverse Event of Special Interest
Time frame: Up to 98 days post administration
Not enrolling at this site.
Plan to share: No
No publications or documents are linked to this record.
Started Oct 2025 (actual). Primary completion is estimated for Feb 2027, 16 months after the start.
Of 16 phase 4 interventional studies under Fever, half reached primary completion within 17 months of starting (the median), counting those still running; a quarter within 11 and three quarters within 42. This study's planned 16 months is close to that.
How these figures are worked out, and which studies are left out of them.
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Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Studies of the drug tested here: Nirsevimab