Sanofi-AstraZeneca's Nirsevimab Hits Primary Endpoint Goal In Late-Stage RSV Disease In Infants

Sanofi SA SNY and AstraZeneca Plc’s AZN monoclonal antibody (mAb) nirsevimab has reached its primary endpoint in a Phase 3 trial, demonstrating protection against respiratory syncytial virus disease (RSV) in healthy infants.
The data comes earlier than anticipated; regulatory submissions for all-infant indications are expected to begin in 2022.
Nirsevimab, an investigational extended half-life mAb is designed to protect infants entering their first RSV season when they are at a higher risk for developing severe RSV disease.
In the Phase 3 MELODY trial, nirsevimab reduced lower respiratory tract infections (LRTI) requiring medical attention due to RSV in healthy preterm and term infants.
There were no clinically meaningful differences observed in the safety results between the nirsevimab and placebo groups. The overall safety profile for nirsevimab in the trial remained consistent with previously reported results.
Sanofi and AstraZeneca are also evaluating nirsevimab in a Phase 3 trial to assess the safety and tolerability of the mAb compared to Sobi’s Synagis (palivizumab) among preterm infants and children with chronic lung disease (CLD) and congenital heart disease (CHD) entering their first and second RSV seasons.
Price Action: AZN shares are up 0.63% at $52.59, while SNY stock is down 0.06% at $51.65 in the premarket on the last check Monday.