African Americans have a higher incidence of chronic hepatitis C than Caucasians. However, African Americans have often been under represented in clinical trials of interferon therapy.
This latest study, by Dr J Kinzie and colleagues in Detroit, USA, compares the end-of-treatment response to interferon in 61 African Americans and 49 Caucasians with chronic hepatitis C.
All patients were treated with interferon-alpha-2b three times weekly for at least 12 weeks.
| Only 8% of African Americans responded to interferon treatment.|
|Journal of Viral Hepatitis|
End-of-treatment response was defined as three consecutive non-detectable HCV RNA measurements at least 1 month apart. Patients were defined as having a sustained response to treatment if serum HCV RNA was negative 6 months after treatment.
19 out of the 110 patients (17%) achieved an end-of-treatment response. Only 4 patients showed a sustained response to the treatment.
In Caucasians end-of-treatment response was seen in 14 of 49 patients (31%). Response to treatment was significantly worse in African Americans with only 5 of 61 patients (8%) achieving and end-of-treatment response.
Hepatitis C viral genotype was an important predictor of response to interferon treatment. End-of-treatment response was 7% for patients with viral genotype 1 compared to 71% in patients with other viral genotypes.
Only 2% of African Americans with viral genotype 1 responded to treatment, compared to 15% of Caucasians with genotype 1 hepatitis C.
The lower response rate for African Americans with viral genotype 1 was seen as the main reason for the difference in overall treatment success between African Americans and Caucasians.
Dr Kinzie concludes, "Caucasians were more likely to respond than African Americans, especially in patients with genotype 1."