Nirsevimab MEDLEY phase II/III trial demonstrated favourable safety and tolerability profile in infants at high risk of respiratory syncytial virus.- AstraZeneca + Sanofi

Occurrence of treatment emergent adverse events (TEAEs) or treatment emergent serious adverse events (TESAEs) were similar between groups. Nirsevimab is a long-acting antibody, using AstraZeneca’s proprietary YTE technology, being developed by AstraZeneca and Sanofi with the potential to provide immunity directly to all infants and offer immediate protection against RSV through the entire season with a single dose.

Dr Joseph Domachowske, Professor of Pediatrics and Professor of Microbiology and Immunology at the State University of New York, Upstate Medical Center, Syracuse, NY and MEDLEY trial primary investigator, said: “These data for nirsevimab are important as they show a safety and tolerability profile comparable to the only available preventative option against lower respiratory tract infections caused by respiratory syncytial virus for preterm infants and those with health conditions. Given the typical respiratory syncytial virus season lasts nearly five months, there is a potential advantage to providing a preventative option that could help protect all infants with one dose for the entire season.”

Full results from the MEDLEY trial will be presented at a forthcoming medical meeting. The trial is ongoing to collect additional safety data. Nirsevimab is also being evaluated in the MELODY Phase III trial, which met its primary endpoint of a statistically significant reduction in the incidence of medically attended LRTI caused by RSV, compared to placebo, in healthy late preterm and term infants during their first RSV season. MEDLEY, MELODY and the Phase IIb trial will form the basis of AstraZeneca’s regulatory submissions planned from the first half of 2022.