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Friday 19 May 2023

Baby RSV hospitalisations fall by 83 percent in trial

New results from an international study show a treatment could greatly reduce the number of babies admitted to hospital with a common virus.

Respiratory Syncytial Virus (RSV) affects 90% of children before the age of two. It is one of the leading causes of hospitalisation in all infants worldwide.

These new results from the HARMONIE study show nirsevimab, a monoclonal antibody immunisation, could help prevent large numbers of babies with an RSV infection needing hospital care.

Nirsevimab was approved for use in the NHS in November 2022. This study is exploring if it could stop babies being hospitalised with RSV and help the NHS decide how best to use it.

More than 8,000 babies under 12 months old are taking part across France, Germany and the UK, including many families in the Southampton area.

The study is being delivered locally by the NIHR Southampton Clinical Research Facility at University Hospital Southampton (UHS) and by local GPS and hospitals across the region.

The new results have been reported by BBC News in a visit to UHS.

Preventing hospitalisations

RSV often causes only mild illnesses, like a cold. However, for some babies, it leads to more severe lung problems such as bronchiolitis and pneumonia.

Nearly 80% of the children admitted to hospital with RSV are previously healthy.

The trial aimed to see if nirsevimab could protect babies entering their first RSV season.

Babies who received a single dose of nirsevimab showed an 83 percent reduction in hospital admissions compared to babies who had standard care.

Dr Katrina Cathie, UHS consultant paediatrician and Southampton study lead, said: “This is a fantastic result, and I’d like to say a big thank you to all the families who took part across our region.

“Through your help, we’ve been able to show nirsevimab can protect babies against serious RSV infections requiring hospital care.”

Reducing winter pressures

The HARMONIE study is a collaboration between Sanofi and the National Institute for Health and Care Research (NIHR).

Thomas Triomphe, Executive Vice President, Vaccines, Sanofi, said:

“This winter saw higher rates of RSV-related infant hospitalisations than during pandemic or pre-pandemic years. The HARMONIE data demonstrate the real-world impact nirsevimab has on paediatric hospitalisations, and illustrate its importance for infants, their families and public health.”

The results were presented at the 41st Annual Meeting of the European Society for Paediatric Infectious Diseases (ESPID).

Dr Simon Drysdale, Consultant Paediatrician in Infectious Diseases at St. George’s University Hospital NHS Foundation Trust and Co-Chief Investigator of HARMONIE, said:

“RSV-related chest infections lead to high numbers of infants under 12 months old being hospitalised every year. These data reinforce the potential public health benefit of nirsevimab in terms of helping to reduce the strain on hospitals caused each year by RSV.”