AstraZeneca/Sanofi's nirsevimab reduces RSV infection in infants by ~75% in phase 3 trial
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AstraZeneca (NASDAQ:AZN) and Sanofi's (NASDAQ:SNY) single dose antibody nirsevimab met the main goal of a phase 3 trial called MELODY by reducing respiratory tract infections (LRTI) caused by the respiratory syncytial virus (RSV) by 74.5% compared to placebo.
The trial involved healthy infants born at term or late preterm (35 weeks gestational age or greater) entering their first RSV season.
A prespecified pooled analysis of the MELODY and phase 2b trials was also conducted and showed a reduction of hospitalizations with nirsevimab. In term and preterm infants (greater than 28 weeks gestational age), the proposed dose of nirsevimab demonstrated efficacy of 77.3% against RSV-linked hospitalizations.
In the Phase 3 MELODY trial alone, a numerical reduction of the risk of RSV-associated hospitalizations was seen, although not statistically significant. In the nirsevimab arm, six of 994 infants were hospitalized for RSV LRTI, while eight of 496 infants were hospitalized in the placebo arm.
In addition, the MEDLEY Phase 2/3 trial, which evaluated nirsevimab in infants with congenital heart disease (CHD), chronic lung disease (CLD) and prematurity entering their first RSV season, showed that nirsevimab had a similar safety and tolerability profile compared to Synagis (palivizumab).
The companies said the overall safety profile of nirsevimab remained consistent with previously reported results.
In February, AstraZeneca said that the European Medicines Agency accepted its application for nirsevimab under an accelerated assessment for preventing LRTI in all infants through their first RSV season.
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