Palivizumab, a Humanized Respiratory Syncytial Virus Monoclonal Antibody, Reduces Hospitalization From Respiratory Syncytial Virus Infection in High-Risk Infants

Abstract

Abstract Respiratory syncytial virus (RSV) is a leading cause of respiratory illness in high-risk infants. The IMpact-RSV trial investigated whether prophylactic monthly injections of a monoclonal antibody targeting RSV, palivizumab, would safely reduce hospitalizations due to RSV. One thousand five hundred and two formerly preterm infants were randomized in a 2:1 ratio to palivizumab or a placebo in a double-blind approach during a single RSV season. Monthly palivizumab injections resulted in a 55% reduction in RSV-related hospitalizations (4.8% versus 10.6%; 95% confidence interval [CI] 0.38 to 0.72, p <0.001). There were also significant reductions in hospital days (36.4 versus 62.6; p <0.001) and days with supplemental oxygen (30.3 versus 50.6; p <0.001) for the palivizumab group, without significant adverse events.