BACKGROUND: Chronic hepatitis Cvirus (HCV) infection is a cause of major complications in persons who are also infected with the human immunodeficiency virus (HIV).However, the treatment of HCV infection in such persons has been associated with a high rate of intolerance and a low rate of response. We conducted a multicenter,randomized trial comparing peginterferon plus ribavirin with interferon plus ribavirin for the treatment of chronic hepatitis C in persons coinfected with HIV. METHODS: A total of 66 subjects were randomly assigned to receive 180 μ g of peginterferon alfa-2a weekly for 48 weeks, and 67 subjects were assigned to receive 6 million IU of interferon alfa-2a three times weekly for 12 weeks followed by 3 million IU three times weekly for 36 weeks. Both groups received ribavirin according to a dose-escalation schedule. At week 24, subjects who did not have avirologic response (those who had an HCV RNA level greater than or equal to 60 IU per milliliter) underwent liver biopsy, and medications were continued in subjects with either a virologic response or histologic improvement.RESULTS: Treatment with peginterferon and ribavirin was associated with a significantly higher rate of sustained virologic response (an HCV RNA level of less than 60 IU per milliliter 24 weeks after completion of therapy) than was treatment with interferon and ribavirin (27 percent vs.12 percent, P=0.03). In the group given peginterferon and ribavirin, only 14 percent of subjects with HCV genotype1 infection had a sustained virologic response (7of 51), as compared with 73 percent of subjects with an HCV genotype other than 1 (11 of 15, P< 0.001). Histologic responses were observed in 35 percent of subjects with no virologic response who underwent liver biopsy.CONCLUSIONS: In persons infected with HIV, the combination of peginterferon and ribavirin is superior to the combination of interferon and ribavirin in the treatment of chronic hepatitis C. These regimens may provide clinical benefit even in the absence of virologic clearance. The marked discrepancy in the rates of sustained virologic response between HCV genotypes indicates that strategies are needed to improve the outcome in persons infected with HCV genotype 1. BACKGROUND: Chronic hepatitis C virus (HCV) infection is a cause of major complications in persons who are also infected with the human immunodeficiency virus (HIV) .However, the treatment of HCV infection in such persons has been associated with a high rate of intolerance and a low rate of response. We conducted a multicenter, randomized trial comparing peginterferon plus ribavirin with interferon plus ribavirin for the treatment of chronic hepatitis C in persons coinfected with HIV. METHODS: A total of 66 subjects were randomly assigned to receive 180 μ g of peginterferon alfa-2a weekly for 48 weeks, and 67 subjects were assigned to receive 6 million IU of interferon alfa-2a three times weekly for 12 weeks followed by 3 million IU three times weekly for 36 weeks. Both groups received ribavirin according to a dose -escalation schedule. At week 24, subjects who did not have avirologic response (those who had an HCV RNA level greater than or equal to 60 IU per milliliter) underwent liver b iULTS, and medications were continued in subjects with either a virologic response or histologic improvement .RESULTS: Treatment with peginterferon and ribavirin was associated with a significantly higher rate of sustained virologic response (an HCV RNA level of less than 60 IU per milliliter for 24 weeks after completion of therapy) was was treated with interferon and ribavirin (27 percent vs. 12 percent, P = 0.03). In the group given peginterferon and ribavirin, only 14 percent of subjects with HCV genotype 1 infection had a sustained virologic response (7 of 51) , as compared with 73 percent of subjects with an HCV genotype other than 1 (11 of 15, P <0.001). Histologic responses were observed in 35 percent of subjects with no virologic response who underwent liver biopsy. CONCLUSIONS: In persons infected with HIV , the combination of peginterferon and ribavirin is superior to the combination of interferon and ribavirin in the treatment of chronic hepatitis C. These regimens may provide clinic al benefit even in the absence of virologic clearance. The marked discrepancy in the rates of sustained virologic response between HCV genotypes indicates that strategies are needed to improve the outcome in persons infected with HCV genotype 1.