AstraZeneca’s Antibody Favorable in RSV in Phase 2/3 Trial

AstraZeneca recently announced that its long-acting antibody, nirsevimab, demonstrated positive safety and tolerability profile in infants at high risk of respiratory syncytial virus (RSV) in a Phase 2/3 clinical trial. 

The MEDLEY 2/3 trial evaluated nirsevimab compared to Synagis when given to infants with chronic lung disease, congenital heart disease, prematurity, or those entering their first RSV season.

“Respiratory syncytial virus is the leading cause of hospitalisations in infants. These results, combined with the recent positive efficacy outcome of our MELODY Phase III trial and our Phase IIb data, contribute to the body of evidence demonstrating nirsevimab’s potential to protect all infants against respiratory syncytial virus with one dose,” Mene Pangalos, executive vice president of Biopharmaceuticals research and development at AstraZeneca said in the announcement. 

“We look forward to sharing the results with regulators,” Pangalos continued. 

AstraZeneca developed Nirsevimab in partnership with Sanofi using its YTE technology. The antibody has the potential to provide immunity directly to infants and offer protection against RSV through the entire season with a single dose. 

Full results from MEDLEY will be presented in the near future. The ongoing trial will collect additional safety data. 

“Respiratory syncytial virus is the major remaining paediatric infectious disease with no preventative option available to all infants. We believe nirsevimab has the potential to become an important and innovative routine immunisation for all infants — those born prematurely or at term, healthy or with health conditions,” said Jean-Francois Toussaint, global head of research and development at Sanofi. 

Nirsevimab is also being evaluated in the MELODY Phase 3 trial. 

Recently, the trial met its primary endpoint of a statistically significant reduction in the incidence of medically attended lower respiratory tract infection caused by RSV, compared to placebo, in healthy late preterm and term infants during their first RSV season.

The MEDLEY and MELODY Phase 2b trial will form the basis of AstraZeneca’s regulatory submissions planned from the first half of 2022, the company stated. 

Joseph Domachowske, MD, professor of pediatrics, microbiology, and immunology at the State University of New York, said that this data for nirsevimab is important to show a safety profile comparable to the only available preventative option against lower respiratory tract infections caused by RSV for preterm infants and those with health conditions.