By Anthony J. Brown, MD
WESTPORT, CT (Reuters Health) – Interferon alfa-2b plus ribavirin therapy is now the standard initial treatment for patients with chronic hepatitis C, but a report published in the September 22nd issue of The Lancet indicates that a peginterferon-based regimen achieves higher sustained virologic response (SVR) rates.
Previous studies have shown that peginterferon can achieve SVR rates that are twice that of standard interferon. However, relapse rates are high with peginterferon monotherapy and most patients with hepatitis C virus (HCV) genotype 1 infection, the most common and difficult to treat form of infection, do not achieve SVR.
In the current study, Dr. Michael P. Manns, from the Medizinische Hochschule in Hannover, Germany, investigated the effects of peginterferon alfa-2b in combination with ribavirin on viral suppression. Based on findings with standard interferon therapy, the researchers were hopeful that adding ribavirin to the peginterferon regimen would reduce the relapse rate.
The study included 1530 patients with chronic hepatitis C who were randomized to receive 3 MU of interferon subcutaneously three times a week, or 1.5 or 0.5 micrograms/kg per week of peginterferon. Subjects also received non-weight-adjusted daily doses of ribavirin. Twenty-four weeks after the 48-week treatment course, the patients' serum was analyzed for the presence of HCV RNA.
The higher dose peginterferon group had a SVR rate of 54%, significantly higher than the 47% rate found in each of the other groups, Dr. Manns told Reuters Health. "The benefits of the higher dose regimen were most apparent for patients infected with the HCV genotype 1," he noted.
"Based on intention-to-treat analysis, the SVR rate for patients with genotype 2 and 3 was about 80% for each of the regimens," Dr. Manns said. "However, if you consider only patients who completed the full treatment course, the rate is closer to 90%."
Dr. Manns pointed out that further analysis revealed that the SVR rate associated with the higher dose regimen would have been even higher if the ribavirin had been dosed according to weight.
Dr. Mann predicts that "peginterferon plus ribavirin will become the standard treatment for chronic hepatitis C." Not only is it more effective than standard interferon therapy, "but it also is given just once a week as opposed to three times a week," he added.