Inhibition of dengue virus replication by amantadine hydrochloride

Abstract

The effect of amantadine hydrochloride (1-adamantanamine hydrochloride) on dengue virus replication was examined in vitro. Amantadine decreased the titers of all 4 types of dengue viruses grown in LLC-MK2 [rhesus monkey kindey] cells by greater than 90% at concentrations of 50 .mu.g/ml. There was no evidence for any cytopathic effect of the drug of concentrations less than 100 .mu.g/ml. Studies of the time of addition showed that the antiviral effect was maximal when drug was added to virus cultures immediately after the viral adsorption period. In addition, amantadine caused a marked reduction in the growth of dengue virus type 2 in both human and rhesus peripheral blood leukocytes without affecting cell viability. These findings demonstrate that amantadine significantly inhibits the replication of dengue viruses in vitro and indicate a need to determine the efficacy of this drug against dengue virus infections in vivo.