Newcastle Hospitals was one of 150 sites in the UK to run the HARMONIE study, which aimed to find out if a one-off antibody helped to protect babies from respiratory syncytial virus (RSV).
RSV is a common seasonal virus that infects nearly all babies by their second birthday. For most, RSV is mild and like a cold, but for others it leads to more severe illness, such as bronchiolitis, requiring hospital admission for oxygen and tube feeding.
Previous smaller studies have shown that the antibody called nirsevimab, works well and protects babies against RSV in one dose.
The aim of HARMONIE was to test the antibody on a larger group and determine if it reduced the number of babies admitted to hospital with the virus.
Study results, recently published by Sanofi, show that nirsevimab resulted in an 83% reduction in the number of babies admitted to hospital with RSV.
Professor Marieke Emonts-le Clercq, consultant paediatrician at Newcastle Hospitals, led the study locally with support from the trust’s paediatric research team.

“The results of the study are very encouraging and reinforce the benefits of nirsevimab in helping to protect babies from becoming very poorly and needing hospital care,” she said.
“I’d like to thank everyone who volunteered to be part of the study, and the paediatric research team who played a huge part in setting up and delivering HARMONIE in Newcastle.”
In addition to reducing hospital admissions, nirsevimab also reduced severe RSV-related lower respiratory tract disease (LRTD – patients whose oxygen level is under 90% and need additional oxygen supply) by over 75%.
Nirsevimab also reduced the number of all-cause LRTD hospitalisations compared to babies who didn’t receive the RSV vaccine by over 58%.
Data was collected between the 2022-23 RSV seasons and the trial recruited more than 8,000 infants across almost 250 sites in France, Germany, and the UK.
The study was supported by the National Institute for Health and Care Research (NIHR), which supports patients, the public and health and care organisations across England to participate in high-quality research. It was also supported by the PEDSTART network (France) and NETSTAP e.V.(Germany).
For more information about our research, visit www.newcastle-hospitals.nhs.uk/about/research/