Sylvestre treated 76 methadone-maintained patients at two drug-treatment facilities which provide comprehensive primary care for medical and psychiatric problems . of 28C94%. In studies with contrast groups, no significant differences in Epimedin A1 SVR between methadone and contrast groups were found. Excellent completion rates of antiviral therapy (72C100%) were found in five of six studies. There are many barriers to methadone maintenance patients receiving antiviral therapy, and research on overcoming barriers is discussed. Liver transplantation has been successful in methadone maintenance patients but has not been utilized widely. Conclusion High quality medical care for all aspects of HCV infection can be provided to methadone maintenance patients. The literature supports the effectiveness of such services, but the reality is that most patients do not receive them. reported a modest decrease in SVR rate in patients with a pre-existing psychiatric history . Table 1 Prospective studies of antiviral therapy for chronic hepatitis virus infection in methadone maintenance patients. (2003) ,(2004) ,(2007) ,(2007) ,(2007) ,= 0.01). ?Average methadone dose decreased by 5 mg in those who completed antiviral CD14 therapy. Includes buprenorphine patients: 38% in Belfiori  and 18% in Krook . ?Average methadone dose increase of 20 mg. The superscript numbers 1, 2 and 3 serve to link data from each of the three contrast groups in both studies by Schaefer . The quality of this published work on antiviral therapy of HCV in methadone maintenance patients is variable. As Mauss indicate, a randomized trial comparing HCV treatment in patients on, versus not on, opioid maintenance, is not feasible . Five of the papers listed in Table 1 provided inclusion and exclusion criteria, and one did so partially . In two [7,1 5] of the three studies with contrast groups there Epimedin A1 were some baseline differences between the methadone and contrast groups. Mauss matched control patients for sex, age, HCV genotype and HCV-RNA . Five of the six studies used an ITT analysis. One group from Norway planned to study all genotypes but Epimedin A1 decided later to publish data only on genotype 3, Epimedin A1 the predominant genotype there, because only three non-genotype-3 patients were enrolled . Four reports described withdrawals and dropouts adequately, one did so partially  and one had no dropouts . Three studies compared methadone patients with and without SVR [9,10, 15]. None address the issue of HCV re-infection after SVR; a few studies of this in drug users who continue to inject describe a low incidence [91,92]. We conclude that the literature strongly supports the feasibility of antiviral therapy in methadone maintenance patients with HCV infection. This treatment can be effective, but additional studies with larger numbers would allow stronger conclusions regarding efficacy. Future studies should ideally be prospective; should have the study of methadone patients as a specific aim; should include data on the numbers of patients who were evaluated, were eligible for the treatment and who actually entered the study; should compare patients with and without SVR; and should have a prolonged follow-up. There is no scientific or clinical reason to withhold antiviral therapy from methadone or buprenorphine maintenance patients. Three groups have reviewed antiviral therapy for HCV infection in current or former injection drug users, and all support increased efforts to treat such patients [87,93,94]. HIV AND HCV CO-INFECTION Injection drug use is a major route of transmission of both HIV and HCV. Overall, about 15C30% of HIV-positive individuals are co-infected with HCV [95,96]. In methadone maintenance patients, the prevalence of HIV and HCV co-infection will be significantly higher because, as discussed previously, 67C96% of methadone maintenance patients are infected with HCV [31,46C50]. A small number of patients with HIV infection may be seronegative for anti-HCV despite having HCV infection with HCV-RNA positivity . Compared with HCV alone, HIV and HCV co-infection is associated with higher HCV-RNA levels [98,99] and a more rapid progression to cirrhosis [98C100]. Co-infected patients who are treated with antiretroviral therapy are living longer and arc thus more likely to develop complications of, and mortality from, HCV-associated liver cirrhosis . Several of the antiretroviral medications used to treat HIV.