The effect of generic market entry on antibiotic prescriptions in the United States

Cecilia Kållberg* (Corresponding Author), Jemma Hudson, Hege Salvesen Blix, Christine Årdal, Eili Klein, Morten Lindbæk, Kevin Outterson, John-Arne Røttingen, Ramanan Laxminarayan

*Corresponding author for this work

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When patented, brand-name antibiotics lose market exclusivity, generics typically enter the market at lower prices, which may increase consumption of the drug. To examine the effect of generic market entry on antibiotic consumption in the United States, we conducted an interrupted time series analysis of the change in the number of prescriptions per month for antibiotics for which at least one generic entered the US market between 2000 and 2012. Data were acquired from the IQVIA Xponent database. Thirteen antibiotics were analyzed. Here, we show that one year after generic entry, the number of prescriptions increased for five antibiotics (5 to 406%)-aztreonam, cefpodoxime, ciprofloxacin, levofloxacin, ofloxacin-and decreased for one drug: cefdinir. These changes were sustained two years after. Cefprozil, cefuroxime axetil and clarithromycin had significant increases in trend, but no significant level changes. No consistent pattern for antibiotic use following generic entry in the United States was observed.
Original languageEnglish
Article number2937
Number of pages9
JournalNature Communications
Issue number1
Publication statusPublished - 18 May 2021

Bibliographical note

C.K. and C.Å. were funded by the DRIVE-AB Consortium. DRIVE-AB is supported by the IMI Joint Undertaking under the DRIVE-AB grant agreement number 115618, the resources of which are composed of financial contributions from the European Union’s Seventh Framework Programme and the European Federation of Pharmaceutical Industries and Associations companies’ in-kind contribution. C.K. and C.Å. were partly supported by the Research Council of Norway through the Global Health and Vaccination Programme (GLOBVAC), project number 234608. K.O. is supported by NOA 06-IDSET160030 from the Biomedical Advanced Research and Development Authority (BARDA) under the Assistant Secretary for Preparedness and Response (ASPR) in the US Department of Health and Human Services, and the CARB-X award from the Wellcome Trust, but the views expressed herein are not necessarily those of CARB-X or any CARB-X funder. J.H. works for Health Services Research Unit, University of Aberdeen, and is core funded by the Chief Scientist Office of the Scottish Government Health and Social Care Directorates. R.L. was supported by 16IPA16092427 from the US Centers for Disease Control and Prevention. The funder provided support in the form of salaries for authors, according to the statement above, but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.


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