Selective estrogen receptor modulator, tamoxifen, inhibits Zika virus infection

Scott F. Grady, Amelia K. Pinto, Mariah Hassert, June A. D'Angelo, James D. Brien, Christopher K. Arnatt

Research output: Contribution to journalArticlepeer-review

3 Scopus citations


Zika virus (ZIKV) is an arbovirus belonging to the flaviviridae family with a risk assessment that has been increasing in recent years and was labeled a global health emergency by the World Health Organization in 2016. There are currently no Food and Drug Administration-approved treatment options available for ZIKV, so expeditious development of treatment options is urgent. To expedite this process, an on-market drug, tamoxifen (TAM), was selected as a promising candidate for repurposing due to its wide range of biological activities and because it has already been shown to possess activity against hepatitis C virus, a flavivirus in a separate genus. Anti-ZIKV activity of TAM was assessed by compound screens using an infectious virus and mechanistic details were gleaned from time of addition and virucidal studies. TAM and an active metabolite, 4-hydroxytamoxifen (TAM-OH), both showed promising antiviral activity (EC50 ≈9 and 5 µM, respectively) in initial compound screening and up to 8-h postinfection, though the virucidal assay indicated that they do not possess any direct virucidal activity. Additionally, TAM was assessed for its activity against ZIKV in the human male germ cell line, SEM-1, due to the sexually transmitted nature of ZIKV owing to its extended survival times in germ cells. Virus titers show diminished replication of ZIKV over 7 days compared to controls. These data indicate that TAM has the potential to be repurposed as an anti-ZIKV therapeutic and warrants further investigation.

Original languageEnglish
Pages (from-to)6155-6162
Number of pages8
JournalJournal of Medical Virology
Issue number11
StatePublished - Nov 2021

Bibliographical note

Funding Information:
This work was supported by Saint Louis University startup funds.

Publisher Copyright:
© 2021 Wiley Periodicals LLC


  • antiviral
  • estrogen modulator
  • flavivirus
  • focus forming
  • tamoxifen
  • zika virus

ASJC Scopus subject areas

  • Virology
  • Infectious Diseases


Dive into the research topics of 'Selective estrogen receptor modulator, tamoxifen, inhibits Zika virus infection'. Together they form a unique fingerprint.

Cite this