Clinical

Interferon and ribavirin therapy for HCV may be too short

Last Updated: 2004-03-29 9:19:59 -0400 (Reuters Health)

NEW YORK (Reuters Health) - Only about half of patients infected with genotype-1 hepatitis C virus (HCV) respond to treatment with pegylated interferon alpha-2b and ribavirin, New York-based researchers report. In some patients, they suggest, this may be due to an insufficient length of therapy.

To investigate, Dr. G. L. Drusano and Dr. S. L. Preston from the Ordway Research Institute in Albany employed a large database of patients treated with a combination of ribavirin and interferon to generate a model predicting sustained viral response to this treatment. They hypothesized that the longer the virus load was undetectable in serum, the better the odds would be of such a response. Current recommendations are for 48 weeks of therapy.

As reported in the March 15th issue of the Journal of Infectious Diseases, the model predicted that patients infected with HCV genotype 1 required continuous nondetectability of virus load in serum for 36 weeks to attain a 90% probability of a sustained response. Nondetectability for 32 weeks attained an 80% probability of a sustained viral response.

"The average time to clear serum of genotype-1 virus was 30.4 weeks," the investigators point out, "which indicates that the 48-week duration of therapy provided a suboptimal probability of a sustained viral response"

Drs. Drusano and Preston emphasize that a prospective trial is needed to prove that failure may be associated with inadequate duration of therapy. However, should this be the case, they conclude that long-term response to this combination treatment could increase by about 14%.

J Infect Dis 2004;189:964-970.