There is a shortage of funds for treating RSV. Here's what doctors recommend:

Recently approved treatment was supposed to protect infants from RSV, but the demand for it exceeds the supply.

In July, the U.S. Food and Drug Administration (FDA) approved nirsevimab, an antibody that attaches to cells and prevents respiratory syncytial virus (RSV) infection. Subsequently, the Centers for Disease Control and Prevention (CDC) recommended this medication for all children born during the RSV season or for children under eight months old entering their first RSV season, which typically runs from November to March. RSV can be a dangerous and potentially deadly disease, especially for infants; according to the CDC, in the United States, annually, between 58,000 and 80,000 children under five years old are hospitalized, and up to 300 die from RSV.

The antibody is not a treatment for RSV since it prevents infection rather than treats it, but it is not a vaccine either, even though it works similarly and provides short-term protection to infants. The antibodies in the shot essentially replace the antibodies that infants cannot yet produce in sufficient quantities to fend off the virus. Since it's not a vaccine, it's crucial for children to receive the antibodies at the right time, during the RSV season, to increase their chances of avoiding infection.

Why is there a shortage of nirsevimab? However, on October 23, the CDC warned healthcare providers about the shortage of the drug and recommended reserving available doses for infants at the highest risk of RSV complications, including children aged six months and younger, as well as individuals with heart and lung conditions. In response to the warning, pediatricians informed parents that if their children do not meet these criteria of increased risk, they will not be able to receive the medication.

Sanofi, which distributes nirsevimab (sold under the brand name Beyfortus) in partnership with AstraZeneca, the manufacturer, noted an unexpectedly high demand for the drug leading to a shortage. A representative from Sanofi says, "Despite an aggressive supply plan designed to outperform previous pediatric immunization launches, demand for this product... has been higher than expected." According to an AstraZeneca representative, to address the shortage issue, "we are maximizing the efficiency of our manufacturing capabilities and recently added additional manufacturing and packaging capacity through the addition of other manufacturing sites."

Dr. Robert Frenk, a professor of pediatrics and director of vaccine research at Cincinnati Children's Hospital, says several factors likely contributed to the insufficient supply, including pent-up demand that hit all vaccines at once and the difficult financial decisions doctors had to make about how many doses to order. Since antibodies are recommended for children under eight months old in their first RSV season, any child born as late as March is now eligible for nirsevimab. In the United States, approximately 3.5 million children are born annually, and that's about 2.4 million children possibly coming into doctors' offices and hospitals to receive the medication.

The good news is that the mismatch will likely be resolved by next year. While there will always be a surge in demand for the drug just before the RSV season, next year it's quite likely that children born in the fall will receive nirsevimab before being discharged from the hospital, partially reducing the demand as the RSV season begins. "This year, we suddenly had millions of kids who needed it, and we couldn't allocate it based on when they were born," says Frenk.

There's another artifact of introducing any new drug that likely also contributed to shortages in some doctors' offices, and it's related to how doctors prescribe medications. Private practice pediatricians pay for drugs upfront, expecting reimbursement from insurance providers. The CDC included nirsevimab in the "Vaccines for Children" program, which means the government will cover the cost of the drug for children who are underinsured or uninsured, which accounts for about half of the children born in the country each year. The other half is covered by private payers, and while these insurers are obligated to reimburse for drugs included in the "Vaccines for Children" program, the extent of coverage and the timeliness of establishing administrative procedures for reimbursement vary from company to company. Given the approximate cost of a dose at $450, some doctors had to make tough decisions about how much nirsevimab to order, and those who delayed are no longer able to place orders due to the shortage. "Private insurance companies are not one beast," says Dr. Jessie Hackell, chair of the practice and ambulatory medicine committee at the American Academy of Pediatrics (AAP). "Having a requirement for insurance doesn't mean that the reimbursement gets loaded into the system [of every insurance company]. [As a pediatrician], you wouldn't want to submit a claim to the insurance company without knowing beforehand that it won't just be denied as an unrecognized code."