Palivizumab prophylaxis reduces hospitalization due to respiratory syncytial virus in young children with hemodynamically significant congenital heart disease

Objectives To evaluate the safety, tolerance, and efficacy of palivizumab in children with hemodynamically significant congenital heart disease (CHD). Study design A randomized, double-blind, placebo-controlled trial included 1287 children with CHD randomly assigned 1:1 to receive 5 monthly intramuscular injections of 15 mg/kg palivizumab or placebo. Children were followed for 150 days. The primary efficacy end point was antigen-confirmed respiratory syncytial virus (RSV) hospitalization. Results Palivizumab recipients had a 45% relative reduction in RSV hospitalizations (P = .003), a 56% reduction in total days of RSV hospitalization per 100 children (P = .003), and a 73% reduction in total RSV hospital days with increased supplemental oxygen per 1100 children (P = .014). Adverse events were similar in the treatment groups; no child had drug discontinued for a related adverse event. Serious adverse events occurred in 55.4% of palivizumab recipients and 63.1% of placebo recipients (P < .005); none were related to palivizumab. Twenty-one children (3.3%) in the palivizumab group and 27 (4.2%) in the placebo group died; no deaths were attributed to palivizumab. The rates of cardiac surgeries performed earlier than planned were similar in the treatment groups. Conclusions Monthly palivizumab (15 mg/kg IM) was safe, well-tolerated, and effective for prophylaxis of serious RSV disease in young children with hemodynamically significant CHD.