Protective Effect of Intranasal Regimens Containing Peptidic Middle East Respiratory Syndrome Coronavirus Fusion Inhibitor Against MERS-CoV Infection

J Infect Dis. 2015 Dec 15;212(12):1894-903. doi: 10.1093/infdis/jiv325. Epub 2015 Jun 8.


To gain entry into the target cell, Middle East respiratory syndrome (MERS) coronavirus (MERS-CoV) uses its spike (S) protein S2 subunit to fuse with the plasma or endosomal membrane. Previous work identified a peptide derived from the heptad repeat (HR) 2 domain in S2 subunit, HR2P, which potently blocked MERS-CoV S protein-mediated membrane fusion. Here, we tested an HR2P analogue with improved pharmaceutical property, HR2P-M2, for its inhibitory activity against MERS-CoV infection in vitro and in vivo. HR2P-M2 was highly effective in inhibiting MERS-CoV S protein-mediated cell-cell fusion and infection by pseudoviruses expressing MERS-CoV S protein with or without mutation in the HR1 region. It interacted with the HR1 peptide to form stable α-helical complex and blocked six-helix bundle formation between the HR1 and HR2 domains in the viral S protein. Intranasally administered HR2P-M2 effectively protected adenovirus serotype-5-human dipeptidyl peptidase 4-transduced mice from infection by MERS-CoV strains with or without mutations in the HR1 region of S protein, with >1000-fold reduction of viral titers in lung, and the protection was enhanced by combining HR2P-M2 with interferon β. These results indicate that this combination regimen merits further development to prevent MERS in high-risk populations, including healthcare workers and patient family members, and to treat MERS-CoV-infected patients.

Keywords: MERS-CoV; fusion inhibitor; interferon; peptide.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Intranasal
  • Animals
  • Antiviral Agents / administration & dosage*
  • Cell Line
  • Coronavirus Infections / prevention & control*
  • Disease Models, Animal
  • Humans
  • Lung / virology
  • Mice, Inbred C57BL
  • Middle East Respiratory Syndrome Coronavirus / drug effects
  • Middle East Respiratory Syndrome Coronavirus / physiology*
  • Peptides / administration & dosage*
  • Viral Load
  • Virus Internalization / drug effects*


  • Antiviral Agents
  • Peptides