Implications of rapid virological response in hepatitis C therapy in the US veteran population

Early predictors of response to hepatitis C virus (HCV) therapy, such as rapid virological response, are valuable for the identification of patients with a higher likelihood of treatment success.

To identify predictors of rapid virological response in a real world setting.

Using the VA Clinical Case Registry, we identified patients with HCV mono-infection, without liver transplantation, who initiated peginterferon (PEG-IFN) and ribavirin (RBV) in 2007 or 2008 and had HCV RNA testing for RVR. Significant baseline characteristics from genotype specific univariate analyses were used in backwards stepwise models to identify significant independent predictors of RVR.

The final cohort consisted of 2424 patients with genotype 1 (G1), 666 patients with genotype 2 (G2), and 419 patients with genotype 3 (G3). Rapid virological response rates were 15% for G1, 71% for G2 and 57% for G3. Sustained virological response rates were significantly higher in patients with rapid virological response than without, increasing from 18% to 52% in G1, 39% to 71% in G2, and 40% to 60% in G3 (P < 0.0001). A baseline HCV RNA < 500,000 IU/mL positively predicted RVR across all genotypes studied. In addition, for G1, Black race, Hispanic ethnicity, aspartate aminotransferase/alanine aminotransferase (AST/ALT) ≥ 0.6, ferritin ≥ 350 ng/mL, LDL< 100 mg/dL and diabetes; for G2, BMI ≥ 30 kg/m(2), platelets < 150 K/μL, LDL< 100 mg/dL and the use of PEG-IFN alfa-2b; and for G3, AST/ALT ≥ 1.0, all negatively predicted rapid virological response.

We found several novel independent predictors of rapid virological response, including BMI, AST/ALT ratio, ferritin, platelets, LDL, diabetes and type of PEG-IFN prescribed, which may be useful in guiding treatment decisions in routine medical practice.