Results from a phase 3 trial evaluating AstraZeneca and Sanofi’s jointly developed treatment nirsevimab – the first investigational long-acting antibody, designed to protect all infants from respiratory syncytial virus (RSV), with a single dose – have produced significant findings. The trial involved healthy infants entering their first RSV season.
The vaccine, nirsevimab, reduced lower respiratory tract infections, caused by RSV and requiring medical care in healthy infants by nearly 75% in the phase 3 MELODY trial. These infections include those such as bronchiolitis or pneumonia. In preterm infants – those between 28- and 37-weeks gestational age – the vaccine demonstrated over 77% efficacy against RSV-associated hospitalisations.
“We know that RSV has seen a resurgence with the easing of COVID-19 public health measures,” said Dr William Muller, associate Professor, paediatrics, Northwestern University Feinberg School of Medicine. “This shows us a broad immunisation approach is needed to help mitigate the substantial global burden RSV places on infants, their families and healthcare services. The exciting data shows that nirsevimab has the potential to offer RSV protection for all infants, which would be a paradigm shift in the approach to this disease.”
RSV is a common and contagious virus, causing seasonal epidemics of lower respiratory tract infections, leading to bronchiolitis and pneumonia in infants. It is a leading cause of hospitalisation in infants.
“With three pivotal late-stage trials, our research has been focused on delivering a first-in-class RSV prevention for all infants,” added Jean-François Toussaint, global head of research and development Vaccines, Sanofi. “Our phase 3 MELODY results in healthy late preterm and term infants represent a major milestone toward that goal. We are pleased Nirsevimab has the potential to become the first immunisation to protect all infants across the RSV season, with only a single dose.”
In 2015 there were approximately 30 million cases of acute lower respiratory infections worldwide, leading to more than three million hospitalisations. It was estimated there were 60,000 in-hospital deaths of children younger than five years.