Avian Flu Diary: CDC HAN Advisory #00499: Limited Availability of Nirsevimab in the United States

#17,734

Last July the FDA Approved a New Drug to Prevent RSV in Babies and Toddlers called Nirsevimab - a monoclonal antibody with activity against Respiratory Syncytial Virus. In early September the CDC issued a HAN Advisory #00498 reporting increased RSV activity, particularly in the Southeastern United States.

Among their recommendations to the public, the CDC advised:

Expectant parents, parents of infants under the age of 8 months, and parents with older babies (through age 19 months) at increased risk of severe RSV disease should talk with their healthcare providers about using monoclonal (preventive) antibodies

The most recent RSV National Trends indicates the rates of RSV continue to rise across the nation, but at the same time the manufacturer of Nirsevimab (Sanofi) is reporting supply shortages due to unusually high demand (excerpt follows).

There has been unprecedented demand for Beyfortus™ (nirsevimab-alip). For the first time in history, health care providers are able to help protect an extraordinary number of infants against respiratory syncytial virus (RSV) disease. 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.

Sanofi is in close collaboration with the Centers for Disease Control and Prevention (CDC) to ensure equitable distribution of available doses through the Vaccines For Children Program (VFC). Our 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.

In view of these shortages, last night the CDC issued the following HAN Advisory. I've only posted the summary, clinicians will want to follow the link to read it in its entirety. I'll have a bit more after the break.

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

Distributed via the CDC Health Alert Network
October 23, 2023, 3:30 PM ET
CDCHAN-00499

Summary

The Centers for Disease Control and Prevention (CDC) is issuing this Health Alert Network (HAN) Health Advisory to provide options for clinicians to protect infants from respiratory syncytial virus (RSV) in the context of a limited supply of nirsevimab, a long-acting monoclonal antibody immunization product recommended for preventing RSV-associated lower respiratory tract disease in infants.

In the context of limited supply during the 2023–2024 RSV season, CDC recommends prioritizing available nirsevimab 100mg doses for infants at the highest risk for severe RSV disease: young infants (age <6 months) and infants with underlying conditions that place them at highest risk for severe RSV disease. Recommendations for using 50mg doses remain unchanged at this time. Avoid using two 50mg doses for infants weighing ≥5 kilograms (≥11 pounds) to preserve supply of 50mg doses for infants weighing <5 kilograms (<11 pounds). Providers should be aware that some insurers may not cover the cost of two 50mg doses for an individual infant.

CDC further recommends that providers suspend using nirsevimab in palivizumab-eligible children aged 8–19 months for the 2023–2024 RSV season. These children should receive palivizumab per American Academy of Pediatrics (AAP) recommendations. Nirsevimab should continue to be offered to American Indian and Alaska Native children aged 8–19 months who are not palivizumab-eligible and who live in remote regions, where transporting children with severe RSV for escalation of medical care is more challenging or in communities with known high rates of RSV among older infants and toddlers. Prenatal care providers should discuss potential nirsevimab supply concerns when counseling pregnant people about RSVpreF vaccine (Abrysvo, Pfizer) as maternal vaccination is effective and will reduce the number of infants requiring nirsevimab during the RSV season.

(SNIP)

Recommendations for the Public

Families should be aware of everyday preventive measures to limit the spread of RSV and other respiratory illnesses, including washing hands, covering coughs and sneezes, cleaning frequently touched surfaces, and staying home when sick.
Expectant parents should talk with their healthcare provider about receiving the RSV vaccine (Abrysvo, Pfizer) during pregnancy to protect their infant from severe RSV. CDC recommends that all infants are protected against RSV through either vaccination of the mother with RSV vaccine during pregnancy or giving the infant nirsevimab after birth.
Parents should talk with their healthcare provider about whether nirsevimab is available for their infant.

(Continue . . . )

Drug shortages are not uncommon, with the FDA Drug shortage list showing more than 150 medications Currently in Shortage. The following excerpt is lifted from the FDA's 10th Report to Congress Drug Shortages CY 2022

FDA has seen manufacturers in the United States and abroad continue to experience quality issues and struggle with capacity constraints. Additionally, there were dramatic and rapid changes in demand for some products used to treat infectious diseases such as COVID-19, respiratory syncytial virus (RSV), and seasonal influenza, which has placed additional strain on the pharmaceutical supply chain and made it harder for FDA and manufacturers to avoid drug shortages.

Shortages can delay or deny needed care for patients, creating a potential lapse in medical care. Shortages can also lead prescribers to use second-line alternatives, which may be less effective or pose additional risks compared to the drug in shortage.

Last winter we saw sporadic shortages of influenza antivirals here in the United States (see CDC HAN #0482: Prioritizing Antiviral Treatment of Influenza in the Setting of Reduced Availability of Oseltamivir).

Overnight CIDRAP News carried a report on a recent JAMA Research letter (see Half of US states had antiviral shortages in 2022-23 flu season).

While the 2022-2023 flu season was `. . . classified as high severity among children and adolescents, the fourth season with that classification since the 2009 influenza A(H1N1) pandemic (MMWR)', overall it fell somewhere in the middle of the pack for severity (see chart below).