Monitoring of hepatitis C virus (HCV) treatment response is performed by serial HCV RNA measurements; however, this may not be useful for predicting treatment success or failure with oral direct-acting antiviral agent (DAA) therapies. Liver enzyme levels, which are elevated in chronic HCV and tend to decline on therapy, may serve as a more logistically and economically feasible alternative for monitoring treatment response. The Ottawa Hospital Viral Hepatitis Clinic patients (n=219), receiving interferon-free oral DAA treatments, were assessed for liver enzymes and HCV RNA levels at baseline, week 4 and ≥12 weeks post-treatment. Suppression cut points used for this analysis were ALT ≤ 40U L-1 and AST ≤ 30U L-1. The primary outcome was week 12 sustained virologic response (SVR). By our analysis, all indicators had strong PPV (>90%) but limited NPV (.