CC BY-NC-ND 4.0 · Am J Perinatol 2021; 38(S 01): e201-e206
DOI: 10.1055/s-0040-1709127
Original Article

Unintended Consequences Following the 2014 American Academy of Pediatrics Policy Change for Palivizumab Prophylaxis among Infants Born at Less than 29 Weeks' Gestation

Mitchell Goldstein
1  Division of Neonatology, Department of Pediatrics, Loma Linda University Children's Hospital, Loma Linda, California
Leonard R. Krilov
2  Division of Pediatric Infectious Disease, Children's Medical Center, NYU Winthrop, Mineola, New York
Jaime Fergie
3  Department of Infectious Diseases, Driscoll Children's Hospital, Corpus Christi, Texas
Lance Brannman
4  Biopharmaceutical Medical Department, AstraZeneca, Gaithersburg, Maryland
Sally W. Wade
5  Wade Outcomes Research and Consulting, Salt Lake City, Utah
Amanda M. Kong
6  Life Sciences Department, IBM Watson Health, Cambridge, Massachusetts
Christopher S. Ambrose
4  Biopharmaceutical Medical Department, AstraZeneca, Gaithersburg, Maryland
› Author Affiliations
Funding This study was supported by AstraZeneca (the manufacturer of palivizumab), which owned the U.S. rights to palivizumab at the time this work was completed. The U.S. rights to palivizumab are currently owned by Swedish Orphan Biovitrum AB (Sobi, Inc.).


Objective The aim of this study is to compare outpatient respiratory syncytial virus (RSV) immunoprophylaxis (IP) use and relative RSV hospitalization (RSVH) rates for infants <29 weeks' gestational age (wGA) versus term infants before and after the 2014 American Academy of Pediatrics (AAP) policy change.

Study Design Infants were identified in the MarketScan Commercial and Multi-State Medicaid databases. Outpatient RSV IP receipt and relative <29 wGA/term hospitalization risks in 2012 to 2014 and 2014 to 2016 were assessed using rate ratios and a difference-in-difference model.

Results Outpatient RSV IP receipt by infants <29 wGA and aged <3 months in the Commercial and Medicaid populations and those aged 3 to <6 months in the Medicaid population declined after 2014. Relative RSVH risks for infants <29 wGA were numerically greater after 2014, with infants aged <3 months and Medicaid infants experiencing the greatest increases. Difference-in-difference results indicated a significantly increased relative risk of RSVH for infants <29 wGA versus term (both cohorts aged 0 to <6 months) in the Medicaid-insured population (1.68, p = 0.0054). A nonsignificant increase of similar magnitude occurred in the commercially insured population (1.57, p = 0.2867).

Conclusion The 2014 policy change was associated with a decrease in RSV IP use and an increase in RSVH risk among otherwise healthy infants <29 wGA.

Authors' Contributions

All authors contributed to the study design, interpretation of results, and revisions of the manuscript. All authors had access to the full study analyses and have approved the final version of the manuscript. S.W.W. and A.M.K. contributed to the data analysis.


L.B. and C.S.A. (employees of AstraZeneca) fulfilled all International Committee of Medical Journal Editors requirements for authorship of this manuscript and were therefore involved in study design; the collection, analysis, and interpretation of data; the writing of the manuscript; and the decision to submit the article for publication.

Supplementary Material

Publication History

Received: 06 August 2019

Accepted: 25 February 2020

Publication Date:
16 April 2020 (online)

© 2020. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (

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