Antiviral activity of Viracea against acyclovir susceptible and acyclovir resistant strains of herpes simplex virus

Antiviral Res. 1998 Jul;39(1):55-61. doi: 10.1016/s0166-3542(98)00027-8.


Viracea, a topical microbicide, is a blend of benzalkonium chloride and phytochemicals derived from Echinacea purpurea and is a proprietary formula from Destiny BioMediX Corp. Viracea was tested against 40 strains of herpes simplex virus (HSV): 15 strains (five HSV-1 and ten HSV-2) were resistant to acyclovir (ACV-R) and 25 strains (13 HSV-1 and 12 HSV-2) were susceptible to ACV (ACV-S). The median ED50 of Viracea for the five ACV-R strains of HSV-1 was a 1:100 dilution of the drug with a range of 1:50-1:400. The median ED50 of Viracea for the ten ACV-R strains of HSV-2 was 1:200 with a range of 1:50-1:3200. For the ACV-S strains of HSV-1 and HSV-2, the median ED50 of Viracea was 1:100 and 1:200, respectively. The cytotoxicity of Viracea was evaluated in a standard neutral red dye uptake assay in human foreskin fibroblasts. The cytotoxicity of Viracea approached only 50% at the highest concentration of the drug tested, a 1:2 dilution, indicating that Viracea is non-toxic in this cell cytotoxicity assay. Although the active component(s) in Viracea that has anti-HSV activity is not known, it appears that this extract has good antiviral activity against both ACV resistant and ACV susceptible strains of HSV-1 and HSV-2.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acyclovir / pharmacology*
  • Antiviral Agents / pharmacology*
  • Asteraceae / chemistry
  • Benzalkonium Compounds / pharmacology*
  • Cells, Cultured
  • Drug Resistance, Microbial
  • Herpesvirus 1, Human / drug effects*
  • Herpesvirus 2, Human / drug effects*
  • Humans


  • Antiviral Agents
  • Benzalkonium Compounds
  • Viracea
  • Acyclovir