African Americans Have Lower Response Rates to HCV Therapy

September 5, 2006

NEW YORK (Reuters Health) Aug 29 - African American adults with

chronic hepatitis C virus (HCV) infection are less likely to respond

to standard combination therapy with peginterferon and ribavirin, a

study in the August issue of Gastroenterology confirms.

The reduced response rate among African American patients is not

caused by " the usual predictors such as patient age, gender,

pretreatment serum HCV concentrations, amount of fibrosis in the

liver biopsy nor amount of medication taken, " Dr. D. Howell

of the University of land School of Medicine in Baltimore notes

in a statement issued by the American Gastroenterological Association.

In a multicenter treatment trial, 196 African American and 205

Caucasian American treatment-nave patients with HCV genotype 1

infection and similar baseline characteristics received peginterferon

alfa-2a (180 micrograms/week) and ribavirin (1000 to1200 mg/day) for

up to 48 weeks.

The sustained virologic response rate was 28% in African Americans

compared with 52% in Caucasian Americans, a significant difference

with a p value < 0.0001.

Racial differences in viral responses were evident as early as 4

weeks after the start of treatment, the team notes. Breakthrough

viremia occurred more frequently in African Americans than Caucasian

Americans (13% vs. 6%, p = 0.05), but relapse rates were comparable

(32% vs. 25%, p = 0.30).

The proportion of the total maximum dose of peginterferon and

ribavirin taken was lower among African Americans than Caucasian

Americans. However, in multivariate analysis, this did not account

for the racial difference in sustained virologic response rates.

According to Dr. Howell, " the basis for the racial difference in

virologic response rates is being addressed by ongoing supplementary

studies in genetics, immunology, interferon signaling and

pharmacology, and virology. "

Gastroenterology 2006;131:470-477.

Recommended Posts