June 1, 2004
For 48 weeks, the researchers treated 200 chronic hepatitis C patients -- 100 blacks and 100 non-Hispanic whites -- with peginterferon alfa-2b and ribavirin. The primary end point for the study was a sustained virologic response, defined as a negative test for serum HCV RNA six months after completing therapy.
Ninety-eight percent of patients in both cohorts had genotype 1 infection. The rate of sustained virologic response was higher among non-Hispanic white patients (52 percent) than among black patients (19 percent). In addition, the black patients had significantly lower rates of virologic response at 12 weeks and at the end of treatment. In multivariable analyses examining sociodemographic and clinical characteristics, black race was the only variable significantly associated with the difference in response rate.
"The reason for the differences in response between black patients and non-Hispanic white patients with chronic hepatitis C remains unclear," the researchers reported. "Our findings demonstrate a limitation of current HCV therapy. Many novel therapies are under investigation, and our study highlights the importance of adequate enrollment of all racial and ethnic groups. Further research is also necessary to understand the poor response to therapy for chronic hepatitis C with interferon alfa among black patients, since such an understanding might lead to new therapies for all patients," the researchers concluded.