cell based hcv assay for measuring the ability of compounds to inhibit hcv rna replication an assay of the present invention desirably include a first cytotoxicity assay step which measures the conversion of an indicator solution to a fluorescent product to determine if a test compound is cytotoxic to a cell and a second inhibition assay step to determine if the test compound inhibits hcv rna replication desirably an assay of the present invention includes the use of cells transfected with a hcv replicon the ability of the hcv replicon to replicate is highly dependent on the amounts or activity of host cell factors therefore any slight toxicity may have significant effects on viral protein expression and ultimately on any assay which examines the effect of compounds on hcv replication as such the use of an indicator to assess cytotoxicity in an hcv replicon cell line in an assay of the present invention provides a significant advantage in the ability to address the issue of whether hcv inhibition is due to a specific compound virus interaction or due to a subtle but toxic effect on the cellular replication machinery accordingly the present invention includes a dual assay useful for hts that quantifies both the amount of hcv rna replication inhibitory activity associated with a test compound and the amount of cytotoxicity associated with that test compound the dual assay is desirably conducted in a single well assays of the present invention permit for the mass screening of compounds specifically directed towards hcv replication and permit viral rna as well as viral proteins to be produced at levels consistently detectable using standard immunological and molecular biology methods these consistent levels are amendable for hts of compounds specific.