Nirsevimab Safe for Infants With RSV, Significantly Reduces Hospitalization Incidence

Nirsevimab can reduce hospitalizations by 83.21% in infants younger than 12 months with respiratory syncytial virus (RSV)-related lower respiratory tract infection (LRTI), according to a press release published by Sanofi-Aventis Groupe.

The Hospitalized RSV Monoclonal Antibody Prevention (HARMONIE) phase 3b trial (ClinicalTrials.gov Identifier: NCT05437510) is a large interventional clinical trial to determine the safety and efficacy of a single intramuscular dose of nirsevimab. Real-world data were collected from more than 8000 infants across 250 treatment sites in Germany and the United Kingdom during the 2022 to 2023 RSV season.

Compared with infants who received no RSV intervention, researchers observed that 1 dose of nirsevimab led to reductions in several measures, as follows:

• Hospitalizations due to RSV-related LRTI (83.21%; 95% CI, 67.77-92.04; P <.001);
• Incident hospitalizations due to severe RSV-related LRTI (75.71%; 95% CI, 32.85-92.91; P <.001); and
• Incident all-cause hospitalizations due to LRTI (58.04%; 95% CI, 39.69-71.19; P <.001).

Owing to these findings, “[T]he overall burden on healthcare systems could be reduced significantly if all infants receive nirsevimab,” the researchers noted.