CDC Recommends Rationing of RSV Shot Due to Shortages

ATLANTA — The Centers for Disease Control and Prevention is recommending the rationing of doses of an injection to protect young infants from RSV due to shortages of the recently approved product Beyfortus.

In a health alert issued Monday, the CDC said doctors and other health care professionals administering the shot should prioritize available doses for infants at the highest risk from the respiratory syncytial virus.

In practice that means reserving 1-milligram doses of the antibody manufactured by AstraZeneca and distributed by Sanofi Pasteur for infants under the age of 6 months and those whose underlying health conditions put them at a greater risk from the virus.

RSV is a common, contagious virus that causes infections of the respiratory tract. Most commonly manifesting itself as bronchitis in infants and the common cold in adults, it can also lead to more serious respiratory illnesses, such as pneumonia, in the elderly and those with compromised immune systems.

According to the CDC, the virus is the leading cause of hospitalizations among U.S. infants, with the highest incidence of RSV-related hospitalizations occurring in infants aged 3 months or under.

This past July the Food and Drug Administration approved nirsevimab, which is sold under the name Beyfortus,  for passive immunization to prevent RSV-associated lower respiratory tract disease among infants and young children. 

In August, the CDC’s Advisory Committee on Immunization Practices recommended nirsevimab for all infants under 8 months in age who are born during or entering their first RSV season, and for infants and children aged 8-19 months who are at increased risk for severe RSV disease and are entering their second RSV season. 

The recommended dosing of nirsevimab for infants weighing under 11 pounds is 50 mg. 

For infants who are under 8 months old but weigh more than 11 pounds, the recommended dose is 100 mg.

For infants aged 8-19 months at increased risk of severe RSV disease entering their second season, the recommended dose is 200 mg.

While the rate of infection this year is a challenge on its own, the situation has been compounded by the enormous demand for Beyfortus, which the CDC called “unprecedented.”

“Despite an aggressive supply plan built to outperform past pediatric vaccine launches, demand for this product, especially for the 100 mg doses used primarily for babies born before the RSV season, has been higher than anticipated,” the health alert said.

The CDC and Sanofi are now said to be working in “close collaboration” to ensure equitable distribution of available doses through the agency’s Vaccines for Children Program.  

The agency said its approach for distribution across the private marketplace will be similar.  

“We are working with our Alliance partner in charge of manufacturing, AstraZeneca, to accelerate additional supply and explore a number of actions to extend the manufacturing network,” the CDC alert said.

Recommendations for using 50 mg doses remain unchanged at this time. 

The CDC has recommended that clinicians avoid using two 50 mg doses for infants weighing 11 pounds or more to preserve supply of 50 mg doses for infants weighing under 11 pounds. 

It also notes that providers should be aware that some insurers may not cover the cost of two 50 mg doses for an individual infant.

The CDC goes on to say that prenatal care providers should discuss potential nirsevimab supply concerns when counseling pregnant women about the RSVpreF vaccine (Abrysvo, Pfizer) as maternal vaccination is effective and will reduce the number of infants requiring treatment with the antibody during the RSV season.

The CDC alert comes as reports to the National Respiratory and Enteric Virus Surveillance System, a national laboratory-based surveillance network, indicate RSV transmission has increased to seasonal epidemic levels in the southern United States and is expected to continue to increase in the rest of the country within the next one to two months.

Dan can be reached at [email protected] and @DanMcCue