Background and Aims: African American ethnicity is a well-described negative predictor of treatment outcome for chronic hepatitis C (CHC); however, less is known about the influence of Hispanic and Asian ethnicity. The aim of this subanalysis of the Weight-based Dosing of PegINterferon α-2b and Ribavirin (WIN-R) study was to assess the impact of Asian (n=118), Hispanic (n=289), and white (n=3919) ethnicity on CHC treatment outcomes.
Methods: WIN-R was an investigator-initiated trial in which patients with CHC received pegylated interferon α-2b (1.5 μg/kg/wk) plus a fixed ribavirin dose (800 mg/d) or a weight-based ribavirin dose (800 to 1400 mg/d) for 24 or 48 weeks.
Results: Sustained virologic response was higher in Asian patients than in white patients (56% vs 46%, P=0.041), and higher in Asian and white patients than in Hispanic patients (56% vs 35%, P=0.0001; and 46% vs 35%, P=0.0002, respectively). In genotype 1 patients, sustained virologic response was higher in white and Asian patients than in Hispanic patients (36% and 45% vs 25%, P<0.001 for both comparisons); however, in genotype 2/3 patients, there were no significant differences among ethnic groups. Psychiatric adverse events were less common and anemia was more common in Asians than in white or Hispanic patients. Ribavirin dose reductions were less frequent in Hispanic patients than in white patients, whereas pegylated interferonα-2b dose reductions were more common in white patients than Hispanic patients.
Conclusion: These observations highlight the importance of ethnicity as an integral component of the tailored treatment approach to CHC.