In the latest headache for parents hunting for a new shot to protect babies against respiratory syncytial virus, or RSV, this winter, the manufacturer says it has stopped taking orders for some doses because they are unable to keep up with “unprecedented demand.”
Because of the limited supply, The US Centers for Disease Centers for Disease Control and Prevention recommended on Monday that doctors reserve scarce doses of the new therapy, nirsevimab, which is sold as Beyfortus, to infants at highest risk, those under six months of age and those with underlying health conditions that put them at higher risk for severe disease.
The CDC also recommended that doctors stop using Beyfortus for babies ages 8 through 19 months of age who are eligible for an older protective therapy called palivizumab, or Synagis. That therapy is given to children at high risk of severe disease with RSV because of serious lung or heart conditions. Unlike Beyfortus, which protects babies for 6 months after a single dose, Synagis has to be given once a month through RSV season.
“We are going to protect some children from RSV this year. We’re not going to be able to protect as many as we’d hoped, and that’s frustrating,” said Dr. Buddy Creech, a pediatrician at Vanderbilt and president of the Pediatric Infectious Disease Society.
The new recommendations meant that healthy infants over six months of age may miss out on the new protection.
A recent study of infants who needed intensive care for RSV last season found 81% of them were full term with no underlying medical conditions before they were hospitalized.
Beyfortus was approved by the US Food and Drug Administration and enthusiastically recommended by the US Centers for Disease Control and Prevention over the summer for babies under 8 months of age who are entering their first RSV season. It’s also recommended for certain higher risk toddlers up to age 2.
Respiratory syncytial virus infects the lower lungs causing them to fill with mucus. The tiny airways of infants with RSV can easily become filled with fluid, making it difficult for them to breathe and eat. The infection is the leading cause of hospitalization in infants under 1 year of age.
In early September, the CDC warned doctors that RSV cases were rising in the Southeast, and that such regional increases typically marked the start of RSV season.
Some pediatricians, who were excited to have the new protection for their youngest patients, said they were reluctant to stock Beyfortus, however, after taking a hard look at the cost. The new shots retail for about $500 a dose. Many also had concerns about how much insurance companies would reimburse them for administering it, making it tough for parents to find.
As a result, some parents have been hunting fruitlessly for the shots.
Now one manufacturer says that despite planning based on past rollouts of pediatric vaccinations, demand has outpaced supply.
The immunization is being marketed by a partnership between Sanofi and AstraZeneca.
“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 company, Sanofi, said in a statement posted to its website.
Beyfortus is a dose of long-lasting antibodies that are designed to latch onto the virus to prevent it from making more copies of itself.
The restrictions apply primarily to the 100-milligram dose, the strength used for babies who weigh 11 pounds or more and are going into their first RSV season.
“While deliveries of 100mg doses continue, new orders are not being taken by Sanofi at this time,” a company spokesperson wrote in a statement to CNN.
Because of the limited supply, the CDC also briefly paused ordering of the immunization through its Vaccines for Children program last week. The program since reopened ordering for the 50-milligram shot, the dose given to preemies and newborns up to 11 pounds. They are prioritizing these doses to providers who’ve not yet placed orders, or who initially ordered only a small number of doses, according to an email sent to state immunization managers last week.
The CDC told states it expects more doses will be available from the manufacturer every 2 to 3 weeks, including both the 50- and 100-milligram products.
Pediatricians say the supply hiccups were unexpected.
“We knew there were going to be many barriers to implementation of nirsevimab that we were anticipating, and pediatricians have been working hard to overcome those barriers, but we were assured by the manufacturer that supply would not be one of the barriers,” said Dr. Sean O’Leary, who is chair of the American Academy of Pediatrics Committee on Infectious Diseases, in an article for the AAP News.
The AAP said it has requested more detailed information about how long the shortage will last. In the meantime, doctors who might be considering using two 50-milligram doses in place of a single 100-milligram injection should hold off.
“Using two 50 mg doses in place of a 100 mg dose has not been studied and is not approved or recommended,” the AAP said in a statement to CNN.
The health alert issued by the CDC on Monday advised doctors to counsel people who are pregnant about the new maternal vaccine for RSV, Abryvso, which will also protect a newborn against severe RSV during the first few months of life.
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