The combination therapy of Infergen® plus ribavirin appears to be an effective treatment for patients who have a difficult-to-treat form of hepatitis C, according to a study presented this week at the annual meeting of American Association for the Study of Liver Diseases in Boston.
Researchers tested two doses of Infergen, which is also known as consensus interferon, to see if they could produce a better response rate in 120 hepatitis C patients who had failed to respond to interferon plus ribavirin. Most of the participants were infected with genotype 1, the most difficult-to-treat form of hepatitis C.
According to Dr. James Pennington, a vice president at InterMune, about 50 percent of patients treated for hepatitis C virus do not respond to currently available treatments. When retreated with pegylated interferon alpha plus ribavirin, only 6 percent to 12 percent of the non-responders respond.
The study participants received either low or high doses of Infergen for 12 weeks before their doses of Infergen were equalized and combined with ribavirin for 36 additional weeks.
The researchers measured the progress of the study participants at the end of the study and 24 weeks later. They found sustained viral response rates of 43 percent for the high-dose Infergen group and 37 percent for the low-dose Infergen group.
"Retreatment of standard interferon/ribavirin nonresponder patients with chronic hepatitis C with daily consensus interferon and ribavirin yields high sustained response rates," said lead researcher Dr. Stephan Kaiser of the University of Tuebingen in Germany.
Adverse events caused the dose of Infergen dose to be reduced in 16 percent and discontinued in 7 percent of the patients. The most common cause of adverse events was a reduction in white blood cell and platelet counts. The discontinuation rates and rates of serious adverse events are consistent with standard combination therapy, according to the researchers.
Other sources: InterMune