IN-VITRO AND IN-VIVO ENHANCEMENT OF DDI-ACTIVITY AGAINST RAUSCHER MURINE LEUKEMIA-VIRUS BY RIBAVIRIN

Ribavirin has been reported to enhance the activity of ddI against HIV . We explored this enhancement of antiviral activity in Rauscher murin e leukemia virus (RMuLV) models in vitro and in vivo. The significant finding in these studies was that combinations of the drugs exhibited virus titer reductions that were greater than would be expected if the drug interactions were simply additive. These effects were designated synergistic by the method of Prichard and Shipman (Prichard, M.N. and Shipman, C., Jr. (1990) A three-dimensional model to analyze drug-dru g interactions, Antiviral Res. 14, 181-206). In addition to the antivi ral synergy, we also observed some synergistic toxicity in the animal model.