PediatricCriteria & Principles
Nirsevimab (Beyfortus®, Sanofi) is a seasonal monoclonal antibody that is a passive immunization and confers long−lasting protection from RSV for at least 5 months (the length of a typical RSV season) and is expected reduce the risk of severe RSV disease by approximately 80%.
Nirsevimab is recommended for:
- All infants younger than 8 months born during or entering their first RSV season, including those previously recommended by the American Academy of Pediatrics (AAP) to receive palivizumab;
- Infants and children aged 8 through 19 months who are at increased risk of severe RSV disease and entering their second RSV season, including those previously recommended by the AAP to receive palivizumab.
Inpatient use is restricted to targeted populations during the 2025-2026 RSV Season. Please see the attachments to the right of the screen and restricted use below.
Start date for nirsevimab is October 1, 2025. Pediatric ID approval is not required for use in eligible inpatients from October 1, 2025 to March 31, 2026.
Usual Dose & Administration
First RSV Season - Weight < 5 kg:
50 mg IM Once
First RSV Season - Weight > 5 kg:
100 mg IM Once
Adjustment of Dose & Administration
Indication-Specific Adjustment
Dosing in patients who previously received nirsevimab AND subsequently undergone cardiopulmonary bypass during RSV season
For patients who have previously received nirsevimab AND subsequently undergone cardiopulmonary bypass during RSV season, an additional dose of RSV prophylaxis may be given as soon as the child is stable after surgery and prior to discharge.
Infants in first RSV Season:
Surgery within 90 days of recieving nirsevimab: dose based on body weight at time of additional dose
Surgery more than 90 days since recieving nirsevimab: 50 mg by IM injection regardless of body weight
Infants in second RSV season:
Surgery within 90 days of recieving nirsevimab: 200 mg by two IM injections (2 x 100mg, single dose) regardless of body weight
Surgery more than 90 days since recieving nirsevimab: 100 mg by IM injection, regardless of body weight
Drug-Specific Information
Do not use two 50mg doses for infants weighing ≥5 kilograms (≥11 pounds). 50mg doses should be reserved only for infants weighing <5 kilograms (<11 pounds).
Restricted Use
**For 2025-2026 RSV season**
This RSV season, nirsevimab will be the primary product used for RSV prophylaxis. Inpatient use at DUH is restricted to targeted populations. See current Inpatient Use Criteria on the right side of the screen.
- Doses of nirsevimab may be dispensed October 1 through March 31st without prior ID approval for infants who meet inpatient use criteria. If doses are requested outside of that timeframe, then Dr. Ganga Moorthy or the pediatric ID provider on call.
- Administration of second doses should occur in the outpatient setting. If outpatient administration is not feasible, please discuss with Dr. Ganga Moorthy or the pediatric ID provider on call.
- Recommend administration prior to discharge for eligible infants
Palivizumab (Synagis®) is non-formulary at DUH and not stocked. The medication will no longer be produced after December 31, 2025. If questions arise regarding palivizumab, please contact the Pediatric ASET team.
General Notes
- Up-to-date cost information, click here
- IV antimicrobials outpatient (OPAT) dosing, click here
- Obesity dosing weight recommendations here
- Helpful drug-drug interaction check website here
- When dosing guidance is provided it is important to note the following:
Fixed (ie non weight-based) doses in adults are historically based on a 70 kg patient. Specific disease states or individual patients may warrant dosages that differ from the above recommendations. Since product-specific criteria for dose adjustment based on creatinine clearance exist, consult product information regarding specific recommendations for dosage adjustment based on estimated creatinine clearance.