The preventive treatment developed by the pharmaceutical groups Sanofi and AstraZeneca to protect babies from the virus that causes bronchiolitis has proven effective, according to a study reviewing an immunization campaign carried out for several months in Spain.
“These first real-life data support the idea that nirsevimab”, the Beyfortus molecule, “protects babies against hospitalization for respiratory infections linked to respiratory syncytial virus (RSV)”, concludes the study published Thursday in Eurosurveillance, journal published by the European Center for Disease Prevention and Control (ECDC), an agency of the European Union.
RSV is the leading cause of bronchiolitis, a type of infection that primarily affects infants.
Generally not serious, it can however lead them to the hospital.
Beyfortus is part of a salvo of treatments aimed at limiting RSV infections, others having been developed by Pfizer and GSK.
The latter are vaccines while Beyfortus is a monoclonal antibody, but the idea is in all cases to act upstream.
Several countries, including the United States and France, chose to quickly launch immunization campaigns using Beyfortus, sparking some criticism of an early decision in relation to the available data.
Avoid “between 70% and 84%” of hospitalizations
But the study published in Eurosurveillance and carried out in Spain, another country having launched a campaign using this treatment, confirms its effectiveness in limiting hospitalizations of babies with bronchiolitis.
Researchers estimate that nirsevimab prevented “between 70% and 84%” of hospitalizations for respiratory infections caused by RSV.
These conclusions, in line with the results of the clinical trials of Beyfortus, are also in line with the results of a previous, smaller study, carried out in Luxembourg.
They “potentially announce a significant impact of the nirsevimab immunization program” against bronchiolitis epidemics, underline the researchers.
These can prove to be heavy on health systems, as in 2022-2023 when tens of thousands of babies were hospitalized in France, an unprecedented level for more than a decade.