Reuters Health Information (2012-02-08): Interferon and ribavirin control HCV genotype 6
Drug & Device Development
Interferon and ribavirin control HCV genotype 6
Last Updated: 2012-02-08 14:59:04 -0400 (Reuters Health)
NEW YORK (Reuters Health) - Pegylated interferon and ribavirin are effective against chronic infection with hepatitis C virus (HCV) genotype 6, a recent study shows.
"This large randomized study provides new information on treatment of genotype 6 patients, particularly on shortening duration of therapy in select patients (and) thus limiting costs of an expensive treatment," said Dr. K. Rajender Reddy of the University of Pennsylvania, Philadelphia in an email to Reuters Health.
Genotype 6 (which now includes genotypes 7, 8 and 9) is endemic in Southeast Asia, where it accounts for up to 47% of HCV infections. Once problematic mainly in that part of the world, "in the changing era of increasing migration of populations, it has been recently reported in the United States, as well as in China, Taiwan, and Hong Kong," Dr. Reddy and colleagues wrote in a paper online January 17 in the Journal of Hepatology.
The interferon/ribavirin combination is the standard treatment for HCV, but genotype is considered to be a strong predictor of sustained virological response (SVR) and little is known about response and optimal treatment duration with genotype 6, the investigators say.
The new trial included 105 treatment-na�ve HCV genotype 6 patients in Vietnam who were randomized to 24 or 48 weeks of treatment with pegylated interferon alfa-2a 180 mcg per week and ribavirin 15 mg/kg per day.
The study was not funded, and the patients had to pay for their care. Six dropped out for economic reasons and another seven were lost to follow-up.
Even so, on intention-to-treat analysis the SVR was 60% in the 24-week group and 71% in the 48-week group. The difference was not significant. Corresponding biochemical responses were 63% and 77%.
Rates of virological relapse were 7% with the shorter course of treatment and 5% with the longer course.
Overall, SVR was most likely in those with a rapid virological response. In the 24-week group, 75% of such patients achieved SVR. In the 48-week group, the proportion was 86%.
Rates of hematologic and general adverse events were similar between the two groups, except the rate of anemia was lower with shorter treatment (31% vs 57%).
According to the paper, "24 weeks of therapy in younger patients, with low viral load and rapid virological response appeared equally effective as 48 weeks of therapy and this is likely to have a major economic impact on HCV therapy, in such subpopulations."
In fact, Dr. Reddy noted that the efficacy of shorter-duration therapy is scientifically worth pursuing in larger trials, but given the lack of support for the current study, "challenges are in funding."
"While new drugs are being developed for non-genotype 6 hepatitis C infections," he concluded, "pegylated interferon and ribavirin will remain the standard of care for the foreseeable future for genotype 6 infections."
J Hepatol 2012.