Important: Protecting Infants against RSV amid Nirsevimab Shortage

Column Author:   Yvonne M Carter, MSN, APRN, FNP-C | Division of Infectious Diseases, Research

Column Editor: Angela Myers, MD, MPH | Pediatric Infectious Diseases; Division Director, Infectious Diseases; Medical Director, Center for Wellbeing; Professor of Pediatrics, University of Missouri-Kansas City School of Medicine; Clinical Assistant Professor of Pediatrics, University of Kansas School of Medicine

On October 23^rd 2023, the CDC issued an official health advisory regarding limited availability of nirsevimab in the United States during the 2023-2024 respiratory season.¹ As discussed in last month’s issue of the LINK, nirsevimab (a long-acting monoclonal antibody) is recommended for babies less than 8 months of age born during (or entering) their first RSV season and for certain children 8-19 months of age entering their second RSV season. This year marks the first in history that health care providers have had the opportunity to protect a vast number of infants from RSV by prescribing nirsevimab (Beyfortus) as a preventive measure. And yet, despite an “aggressive supply plan” and a coordinated roll-out, the demand for Beyfortus has been unprecedented—particularly the 100mg dose prefilled syringes used for infants weighing >5kg recommended for babies born before RSV season.^1,2

The drug’s manufacturer, Sanofi, released a statement that it is currently in collaboration with the CDC to ensure “equitable distribution” of available doses through the Vaccines for Children Program (VFC).² In the meantime, the following guidelines have been released for providers as we head into another respiratory virus season.

Due to limited supply during the 2023-2024 respiratory virus season, the CDC is recommending that providers prioritize available nirsevimab 100mg doses for infants weighing >5kg at the highest risk for severe RSV disease. This includes:

• Young infants (ages <6 months)
• Native American and Alaska Native infants aged <8 months
• Infants with underlying conditions that place them at highest risk for severe RSV disease (i.e. premature birth <29 weeks’ gestations, chronic lung disease, congenital heart disease, neuromuscular disease, or are severely immunocompromised)¹

The CDC highlights additional interim recommendations that may apply to healthcare settings experiencing nirsevimab shortages during the 2023-2024 RSV season:

• For infants weighing <5kg, ACIP recommendations for using 50mg doses currently remain unchanged. For infants born before October 2023, a 50mg dose of nirsevimab is recommended now. For infants born during October 2023 or the remainder of RSV season, a 50mg dose of nirsevimab is recommended in the first week of life.
• *The CDC specifically recommends avoiding the use of two 50mg doses for infants weighing >5kg to preserve supply of 50mg doses for infants weighing <5kg. It is also important to note that some insurers may not cover the cost of two 50mg doses for an individual infant.¹

Consider use of palivizumab, if possible:

• For the 2023-2024 RSV season, healthcare providers are advised to suspend use of nirsevimab in palivizumab-eligible children aged 8-19months, per AAP recommendations. For those <8 months, follow AAP recommendations for palivizumab when the recommended dose of nirsevimab is not available.^1,3

Consider access to care and community epidemiology when possible:

• For children who are not eligible for palivizumab and who live in remote regions, i.e. Native American and Alaskan Native children, continue to offer nirsevimab. In these communities and others, where transporting children or escalating medical care for those with severe RSV may prove challenging, it is recommended to continue to prioritize nirsevimab, if possible. The same recommendations apply for communities with high rates of severe RSV among older infants or toddlers.¹

Vaccine is also available for pregnant people to help prevent severe RSV disease in infants:

On September 22, 2023, the CDC recommended the first RSV vaccine to protect newborns. Pfizer’s bivalent RSVpreF vaccine (Abrysvo) may be administered to pregnant women between 32-36 weeks gestation to reduce risk of severe disease from RSV in newborn babies.⁴  Those who qualify should ask about the vaccine as soon as it is available this season. What about Nirsevimab for these babies? Most babies will not need Nirsevimab if they are born more than 14 days after their mother has received the RSVpreF vaccine. However, they may still receive Nirsevimab if: their mother did not receive RSV vaccine during pregnancy, her vaccination status is unknown, or the baby was born within 14 days of maternal RSV vaccination.⁵ The interim recommendations discussed previously will apply on a case-by-case basis for these infants.

Additional considerations for the 2023-2024 respiratory season:

For those planning to visit Grandma and Grandpa this holiday season, GSK’s RSVPreF3 vaccine (Arexvy) vaccine is licensed for use in adults aged 60 years and older.⁶ And what about the older pediatric population? As we recall, it was this time last year that pediatric hospitalizations for RSV reached a record high, with a significantly larger proportion of older children (>2 years) hospitalized for RSV than in prior seasons.⁷ As of June 2023, a clinical trial for Pfizer’s RSVpreF vaccine is underway, looking at its safety and immunogenicity in children 2 to < 18 years of age at high risk of RSV disease.⁸ No preliminary results have yet been released.

Although this year marks the first respiratory virus season that vaccines are available for RSV in addition to COVID-19 and flu, it is important to remember that basic hygiene practices—including handwashing—remain our first line of defense against the spread of disease. Additional prevention practices such as at-home or rapid testing (if available) can help with decision-making and reducing risk this season, as can staying home and avoiding crowds when sick, or masking in high-risk environments. As we head into the final stretch of 2023—a big year for RSV prevention and treatment—we must continue to protect our most vulnerable patients.

References:

1. Limited Availability of Nirsevimab in the United States—Interim CDC Recommendations to Protect Infants from Respiratory Syncytial Virus (RSV) during the 2023-2024 Respiratory Virus Season. Centers for Disease Control and Prevention. Accessed October 26, 2023. https://emergency.cdc.gov/han/2023/han00499.asp#:~:text=In%20the%20context%20of%20limited,risk%20for%20severe%20RSV%20disease.
2. Sanofi Beyfortus^TM (nirsevimab-alip) Statement. Sanofi. Accessed October 26, 2023. https://www.news.sanofi.us/Sanofi-Beyfortus-Statement
3. ACIP and AAP Recommendations for the Use of the Monoclonal Antibody Nirsevimab for the Prevention of RSV Disease. American Academy of Pediatrics. Accessed October 26, 2023. https://publications.aap.org/redbook/resources/25379
4. CDC recommends new vaccine to help protect babies against severe respiratory syncytial virus (RSV) illness after birth. Centers for Disease Control and Prevention. Accessed September 26, 2023. https://www.cdc.gov/media/releases/2023/p0922-RSV-maternal-vaccine.html
5. RSV Immunization for Children 19 months and Younger. Centers for Disease Control and Prevention. Accessed October 4, 2023. https://www.cdc.gov/vaccines/vpd/rsv/public/child.html
6. Healthcare Providers: RSV Vaccination for Adults 60 Years of Age and Over. Centers for Disease Control and Prevention. Accessed October 11, 2023. https://www.cdc.gov/vaccines/vpd/rsv/hcp/older-adults.html#:~:text=In%20May%202023%2C%20the%20Food,)%2C%20and%20AS01E%20adjuvant.
7. Rao S, Armistead I, Messacar K, et al. Shifting Epidemiology and Severity of Respiratory Syncytial Virus in Children During the COVID-19 Pandemic. JAMA Pediatr.2023;177(7):730–732. doi:10.1001/jamapediatrics.2023.1088
8. S. FDA Approves ABRYSVO^TM, Pfizer’s Vaccine for the Prevention of Respiratory Syncytial Virus (RSV) in Infants Through Active Immunization of Pregnant Individuals 32-36 Weeks fo Gestational Age. Pfizer. Accessed October 16, 2023. https://www.pfizer.com/news/press-release/press-release-detail/us-fda-approves-abrysvotm-pfizers-vaccine-prevention-0
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