Sanofi-AstraZeneca Say New Nirsevimab Data Reinforce Efficacy Against RSV
- Sanofi SA (NASDAQ:SNY) and AstraZeneca plc (NASDAQ:AZN) have announced results from a prespecified pooled analysis of nirsevimab in respiratory syncytial virus (RSV).
- Results from the Phase 3 MELODY and Phase 2b nirsevimab trials demonstrated an efficacy (relative risk reduction versus placebo) of 79.5% against medically attended lower respiratory tract infections due to RSV in infants.
- In a separate pooled posthoc analysis of the trials, blood samples taken from infants dosed with nirsevimab exhibited RSV neutralizing antibodies that were approximately 50-fold higher than baseline at Day 151 post-dose.
- Related: AstraZeneca-Sanofi's Nirsevimab Shows 75% Efficacy Against RSV In Healthy Infants.
- RSV neutralizing antibody levels remained greater than 19-fold higher than placebo recipients with no known RSV infection through Day 361, suggesting protection may extend beyond Day 151.
- As reported in previous trials, the safety profile across the nirsevimab and placebo groups remains similar.
- Nirsevimab is the first investigational immunization designed to protect all infants across the RSV season with a single dose.
- Price Action: SNY shares are down 1.36% at $51.46, and AZN stock is down 2.18% at $62.25 during the premarket session on the last check Wednesday.