Application for Nirsevimab Accepted by FDA

The US Food and Drug Administration (FDA) has accepted a Biologics License Application for nirsevimab (Beyfortus; AstraZeneca and Sanofi) as a protection against respiratory syncytial virus (RSV) in newborns.

The submission followed phase 3 MELODY, phase 2/3 MEDLEY, and phase 2b trials which showcased safety and efficacy of nirsevimab. Consistent protection was provided to about 80% of patients in the MELODY and phase 2b trials, and the safety profile of nirsevimab was consistent with placebo and palivizumab.

Nirsevimab is a long-acting antibody provided through a single-dose in the United States, made to help protect newborns from RSV through their first RSV season. The antibody can also provide protection for infants aged up to 24 months through their second RSV season.

The antibody found in nirsevimab works to prevent lower respiratory tract infection caused by RSV. Protection is timely, direct, and rapid, as the immune system does not need to activate for monoclonal antibodies to function.

Sanofi and AstraZeneca began jointly working on nirsevimab in March 2017. If approved, it will be the first protective option available to newborns. Newborns born healthy or with specific health conditions, along with those born at term or preterm, will be eligible for the vaccine.

Throughout the 2022 to 2023 season, there has been a spike of RSV cases in otherwise healthy infants. According to the Centers for Disease Control and Prevention, RSV can lead to severe respiratory illness, making it the number 1 cause of hospitalizations among infants aged under 1 year in the United States.

About 75% of newborn RSV hospitalizations occur in infants born at term with no underlying conditions. The current burden RSV has placed on families is greater than normal, and the American Academy of Pediatrics has asked the White House to declare an emergency so the nation response to the disease may receive support.

The Prescription Drug User Fee Act date is projected by the FDA to be in the third quarter of 2023.

Reference

1. FDA accepts nirsevimab application as first protective option against RSV disease for all infants. Press Release. Sanofi - Aventis Groupe. January 5, 2022. Accessed January 5, 2022. https://www.globenewswire.com/news-release/2023/01/05/2583365/0/en/Press-Release-FDA-accepts-nirsevimab-application-as-first-protective-option-against-RSV-disease-for-all-infants.html