LAUSR

Objectives: To assess the respiratory syncytial virus (RSV) infection incidence rate through the analysis of data collected before and after implementation of a new palivizumab dosing regimen customized for a high-risk Saudi population. Methods: This was a retrospective cohort study performed at Prince Sultan Military Medical City, Riyadh, Saudi Arabia between November 2009 and April 2017 on 1704 high risk Saudi young children and comparing 3 palivizumab regimens: a 4-week interval dosing regimen starting in either November or mid-September and a 3-week interval dosing regimen starting in mid-September. Results: Despite a decrease in the incidence rate of RSV infection with the three-week interval regimen (3.9% versus 5.9% in seasons 1 and 9.1% in seasons 2), we did not find significant differences among the 3 groups. Conclusion: Expanded use of palivizumab in newborn children could improve outcomes, but further investigation and a careful cost analysis are required.