Clesrovimab (EnflonsiaTM) Availability Through the Vaccines for Children (VFC) Program

On June 26, 2025, the Advisory Committee on Immunization Practices (ACIP) recommended clesrovimab, a newly licensed long-acting respiratory syncytial virus (RSV) monoclonal antibody, as an alternative to nirsevimab for infants aged <8 months born during or entering their first RSV season who did not receive protection through maternal RSV vaccination. The recommendations for use of this monoclonal antibody can be found in the Morbidity Mortality Weekly Report dated August 28, 2025. 


EnflonsiaTM will be available for order through the ImpactSIIS Vaccine Ordering Management System (VOMS) beginning October 1, 2025, in both 1-pack and 10-pack prefilled syringes. Ohio will receive biweekly allocations from the Centers for Disease Control and Prevention (CDC). If an allocation is exhausted, ordering will pause until the next replenishment. Providers will be notified of ordering restrictions via the ImpactSIIS message of the day. Upon receipt of the product, providers will be able to begin administration to eligible patients.

Clesrovimab (EnflonsiaTM) Product Information
Enflonsia can be administered to infants aged <8 months born during or entering their first RSV season who did not receive protection through maternal RSV vaccination. EnflonsiaTM is given as a single fixed 105 mg (0.7 mL) dose for all eligible infants, regardless of weight. 


EnflonsiaTM is NOT recommended for infants entering their second RSV season. 
Enflonsia 10-pack

  • VOMS Order Set:  VFC RSV.
  • Presentation: Prefilled syringe; 10 pack.
  • Minimum Order Quantity: 10 doses.

Enflonsia 1-pack

  • VOMS Order Set:  VFC RSV.
  • Presentation: Prefilled syringe; 1 pack.
  • Minimum Order Quantity: 1 dose.

VFC EnflonsiaTM Ordering Caps
Providers should use their VFC provider profile data, current inventory, and historical administration of nirsevimab to help determine appropriate order quantities. A vaccine order may be reduced if there is a large discrepancy between an order amount and a provider’s profile data. 
Orders will be processed on a first-come, first-served basis.

VFC Provider Planning Considerations for Nirsevimab and Clesrovimab

  • Ohio’s existing network of VFC providers serves as the main access point to RSV monoclonal antibody products for VFC eligible patients.
  • Providers who have existing inventory of VFC RSV monoclonal antibody products remaining from the 2024-2025 respiratory season should not place orders for additional products until their inventory is low or nearly depleted.
  • Redistribution of RSV monoclonal antibody products to other VFC enrolled providers is not allowed. Each enrolled provider should place a VFC order only for their eligible patients.
  • VFC providers will have the opportunity to order nirsevimab and clesrovimab throughout the respiratory season.
  • VFC providers are advised to ensure there is adequate vaccine storage space in their refrigerators before placing vaccine orders.
  • The ODH vaccine ordering system, VOMS, is available for providers to place orders 24 hours a day, seven days a week.

RSV Monoclonal Antibody Product Administration
For infants <8 months who are born during or entering their first RSV season (October–March in Ohio), a single dose of either nirsevimab or clesrovimab should be administered shortly before the RSV season, or within one week after birth (ideally during the birth hospitalization) if:
1) The mother did not receive RSV vaccine during pregnancy.
2) The mother’s RSV vaccination status is unknown. 
3) The infant was born ≤14 days after maternal RSV vaccination. Except in rare circumstances, administration of RSV monoclonal antibody is not indicated for most infants who are born ≥14 days after their mother received RSV vaccine.
Nirsevimab is recommended for some children (ages 8–19 months) who are at increased risk for severe RSV disease who are entering their second RSV season.1

RSV Monoclonal Antibody Products:

RSV Monoclonal Antibody Products for infants born during or entering their FIRST RSV season during October 1 through March 31:

  • Clesrovimab (EnflonsiaTM) 105mg (0.7mL): Infants aged <8 mos., regardless of weight.
  • Nirsevimab (Beyfortus) 50mg (0.5mL): Infants aged <8 mos., weighing <11 lb. (<5 kg).
  • Nirsevimab (Beyfortus) 100mg (1.0mL): Infants aged <8 mos., weighing ≥11 lb. (≥5 kg).

RSV Monoclonal Antibody Products for older infants at increased risk1 entering their SECOND RSV season during October 1 through March 31:

  • Nirsevimab (Beyfortus) 100mg (1.0mL): Infants aged 8-19 mos. at increased risk. Two 100mg injections (a total 200mg dose), regardless of weight.

For questions about this information or the VFC Program, please call the ODH Immunization Program at 1-800-282-0546.
Thank you for your continued partnership in protecting Ohio’s children from RSV and other vaccine-preventable diseases.
 

Footnotes:

  1. Nirsevimab: 8- to 19-Month-Old Eligibility Criteria.
  • Young children with chronic lung disease (CLD) of prematurity who required medical support during the six months (diuretic therapy, oxygen, chronic corticosteroid treatment) before the start of the second RSV season.
  • Young children who are severely immunocompromised.
  • Young children with cystic fibrosis who have either:
    • Manifestations of severe lung disease (previous hospitalization for pulmonary exacerbation in the first year of life or abnormalities on chest imaging that persist when stable).
    • Weight-for-length that is less than 10th percentile.
  • American Indian and Alaska Native children.