title: Safety and Effectiveness of Palivizumab in Children at High Risk of Serious Disease Due to Respiratory Syncytial Virus Infection: A Systematic Review.
abstract: BACKGROUND
  Lower respiratory tract infection (LRTI) is the leading cause of infant mortality globally in post-neonatal infants (i.e., 28-364 days of age). Respiratory syncytial virus (RSV) is the most commonly identified pathogen for infant LRTI and is the second most important cause of death in post-neonatal infants. Despite 50 years of RSV vaccine research, there is still no approved vaccine. Therefore, passive immunity with the monoclonal antibody palivizumab is the sole regulatory-approved option for the prevention of serious LRTI caused by RSV in pediatric patients at high risk of RSV disease.
  
  
  METHODS
  We conducted a comprehensive systematic literature review of randomized controlled trials (RCTs), open-label non-comparative clinical trials, and prospective observational studies/registries, and summarized the evidence related to the safety, efficacy, and effectiveness of palivizumab.
  
  
  RESULTS
  The efficacy of palivizumab, as measured by the relative reduction in RSV-related hospitalization rate compared with placebo ranged from 39% to 78% (P < 0.05) in the 2 pivotal RCTs. A meta-analysis of the RSV-related hospitalization rate from 5 randomized placebo-controlled trials yielded an overall odds ratio of 0.41 (95% CI, 0.31-0.55) in favor of palivizumab prophylaxis over placebo (P < 0.00001). Low rates of RSV-related hospitalizations were observed in palivizumab recipients consistently over time in more than 42,000 pediatric subjects across 7 RCTs, 4 open-label non-comparative trials, and 8 observational studies/registries conducted in 34 countries. In addition, among palivizumab-prophylaxed subjects with breakthrough RSV LRTI, rates of intensive care unit admission and mechanical ventilation from RSV hospitalization also were low and consistent across studies. With respect to safety, no differences were observed between palivizumab and placebo in the blinded RCTs.
  
  
  CONCLUSIONS
  Rates of RSV hospitalizations and RSV hospitalization-related endpoints in pediatric subjects who received prophylaxis with palivizumab were low and constant over time and across RCTs, open-label non-comparative trials, and observational studies/registries.
authors.affiliation: AbbVie Inc., North Chicago, IL, USA. colleen.wegzyn@abbvie.com.
authors.forename: Colleen
authors.initials: C
authors.lastname: Wegzyn
authors.affiliation: AbbVie Pte. Ltd, Singapore, Singapore.
authors.forename: Lim Kai
authors.initials: LK
authors.lastname: Toh
authors.affiliation: AbbVie Inc., North Chicago, IL, USA.
authors.forename: Gerard
authors.initials: G
authors.lastname: Notario
authors.affiliation: AbbVie Inc., North Chicago, IL, USA.
authors.forename: Sophie
authors.initials: S
authors.lastname: Biguenet
authors.affiliation: AbbVie Deutschland GmbH & Co KG, Ludwigshafen, Germany.
authors.forename: Kristina
authors.initials: K
authors.lastname: Unnebrink
authors.affiliation: AbbVie Inc., North Chicago, IL, USA.
authors.forename: Caroline
authors.initials: C
authors.lastname: Park
authors.affiliation: MedImmune, Inc., Gaithersburg, MD, USA.
authors.forename: Doris
authors.initials: D
authors.lastname: Makari
authors.affiliation: AbbVie Inc., North Chicago, IL, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Norton
keywords: Efficacy; Palivizumab; Respiratory syncytial virus; Safety; Serious lower respiratory tract infection; Systematic review