With respect to the high rates of relevant anemia in both cohorts (78.9 and 58.6%), the rates of EPO treatment and the start of EPO treatment during RBV treatment (73.6 and 55.1%) were not significantly higher in patients with RBV treatment failure, but there was a significant delay of EPO initiation in patients with treatment failure (after 67.6 ± 49.5 vs. 16.0 ± 15.2 days). Here, EPO is linked to anemia (phenotype).