Risks and prevention of severe respiratory syncytial virus infection among infants and children with pulmonary hypoplasia, airway stenosis, congenital esophageal atresia, inborn errors of metabolism, or neuromuscular diseases in Japan

Background: In March 2024, children with pulmonary hypoplasia, airway stenosis, congenital esophageal atresia, inborn errors of metabolism, and neuromuscular diseases became eligible for palivizumab in Japan. Despite limited epidemiological data, expert consensus guided the recommendation for palivizumab use in these children to ensure its proper application. Objectives: This article outlines the proper use of palivizumab for RSV infection in infants and children with the specified conditions, aiming to enhance understanding of the medical basis for its clinical guidance. Methods: A nationwide survey targeted pediatric specialist facilities. Additionally, an investigator-initiated clinical trial under AMED evaluated palivizumab's efficacy and safety in newborns, infants, and young children with the five high-risk diseases. Results: Palivizumab was given to 23 children aged 24 months or younger with the specified conditions. No RSV-related hospitalizations occurred, and serum concentrations remained therapeutically effective. Adverse events were consistent with existing data, with no serious events linked to palivizumab. Conclusion: Following successful trial results, early approval was granted on March 26, 2024. This article aims to promote the appropriate use of palivizumab for RSV infection in children with the specified conditions through clinical guidance.