Thousands more doses of RSV shot for infants expedited for release amid shortage

Amid an ongoing shortage of nirsevimab, an RSV immunization for young children, the US Centers for Disease Control and Prevention has announced that more than 77,000 additional doses will be distributed “immediately.”

These doses will be going to doctor’s offices and hospitals through the CDC’s Vaccines for Children Program and commercial channels, according to Thursday’s announcement.

Nirsevimab, marketed as Beyfortus, is a long-acting monoclonal antibody administered as an injection to protect infants against severe illness from respiratory syncytial virus or RSV infections, which are the leading cause of hospitalization in infants.

“Helping to ensure the availability of this preventative option to reduce the impact of RSV disease on eligible babies and young children, families and the health care system remains a priority,” Dr. Patrizia Cavazzoni, director of the US Food and Drug Administration’s Center for Drug Evaluation and Research, said in the announcement. “We will continue to use all our regulatory tools to help bring safe, effective and high-quality medicines to the public.”

The CDC and the FDA will continue to be in “close contact” with manufacturers to ensure the availability of more doses through the end of this year and early next year to meet demand, according to the announcement.

The shortage of nirsevimab has public health officers frustrated, especially as the nation heads into the winter – typically the peak time for respiratory viruses to spread.

“It’s a success that mothers want to protect their babies. It’s a success that mothers want to get vaccinated. But we can’t celebrate that success if we don’t have equal access everywhere and supply doesn’t meet demand,” said Lori Tremmel Freeman, chief executive officer of the National Association of County and City Health Officials.

In July, the FDA approved Beyfortus and the CDC recommended it for children under 8 months of age who are entering their first respiratory virus season. The immunization is also recommended for certain high-risk toddlers up to age 2. Nirsevimab is supplied in single-dose prefilled syringes of either 50 milligrams or 100 milligrams.

The shortage of nirsevimab has emerged amid high demand and, because of the limited supply, the CDC recommended in October that physicians prioritize 100-milligram doses of nirsevimab for infants at the highest risk for severe RSV disease. Recommendations for using 50-milligram doses remain unchanged.

RSV infects the lower lungs, causing them to fill with mucus, and the small airways of infants with RSV can easily become filled with fluid, making it difficult for them to breathe and eat. In early September, the CDC warned doctors that RSV cases were rising in the Southeast and that such regional increases typically mark the start of RSV season.

The weekly national average percent of positive tests for RSV has been climbing since September, according to CDC data. So far in the 2023-24 respiratory virus season, the overall rate of people being hospitalized due to causes associated with RSV has been about 7 hospitalizations per 100,000 people.

Among children 4 and younger, as of last week, the rate of hospitalizations related to RSV was 18.8 hospitalizations per 100,000, an increase from the previous week when it was a rate of about 16 hospitalizations for every 100,000 children.

‘We definitely have a challenge’

Ideally, this monoclonal antibody should be given to newborns before they leave the hospital, but it is being distributed through the CDC’s Vaccines for Children program, and most birthing hospitals are not a part of that program. So there appears to be a “mismatch” there, said Dr. Chris DeRienzo, a neonatologist and the chief physician executive for the American Hospital Association.

“Only around 10% to 15% of birthing hospitals have historically participated in that program. So we definitely have a challenge and a mismatch there between the goal and the channel,” DeRienzo said, adding that his group has been in touch with the CDC about the problem since early fall. In early September, the hospital association began to hear from states about some challenges with the rollout of nirsevimab.

“It’s important to remember that the Vaccines for Children program, while authorized at the federal level, is actually implemented at the state level. There’s really a patchwork quilt of approaches taken state-by-state in order to execute on it,” he said. “In one state, for example, in New Hampshire, there’s actually a state law that defines what can be included in the VFC program as a vaccine. There’ve been some challenges because nirsevimab, as a monoclonal antibody, is an immunization. It’s not a vaccine.”

The main concern among the American Hospital Association, relative to the Vaccines for Children program, is that it works well for outpatient pediatric primary care providers who need access to many routine immunizations to administer to children, but the program has not been formatted in a way that makes it convenient for birthing hospitals to participate in order to give just one or two immunizations to newborns.

“I haven’t heard of a state that has even more than 50% of their birthing hospitals that are participating in VFC,” DeRienzo said.

“I have a lot of respect for CDC and their attempts to try to get immunizations out,” he said. “But I think what we’ve learned now is, the VFC program really is a mismatch for the goal of doing that in the initial hospitalization period, and hopefully, as we walk through this RSV season, we’ll be able to open new lanes of access to this immunization moving forward, possibly by evolving components of the VFC program.”

Those new lanes of access may include making sure the onboarding of more birthing hospitals into the program is occurring across states, as well as ensuring that states include nirsevimab in their Vaccines for Children distribution channels. But there’s also the hurdle of cost. For instance, DeRienzo said that the hepatitis B vaccine, which also is given to babies at birth, costs only about $10 per patient, compared with nirsevimab, which costs about $500 per immunization.

“We’re going to have to learn from all the challenges that we’re facing in this first season, both in terms of the distribution channel and the mismatch between the Vaccine for Children’s programs and birthing hospitals, the supply challenges, the dosing challenges, because we’ve seen some of the shortages on 100-milligram bottles, but not on the lower-dose bottles,” DeRienzo said.

“My hope is that as we walk through this season and we, as a health care community, do everything we can together to try to get as much of this product into newborns as we’re able to produce,” he said. “We will then learn from the challenges we’re facing this year and be able to open new pathways to access during the next season and beyond.”

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