BACKGROUND Chronic hepatitis C infection is prevalent among haemodialysis patients. The goal of our study was to determine the efficacy and safety of pegylated interferon alpha-2b in haemodialysis patients with chronic hepatitis C. METHODS We conducted a trial which randomized haemodialysis patients with chronic hepatitis C to 1.0 or 0.5 microg/kg of pegylated interferon alpha-2b subcutaneously, weekly for up to 48 weeks. End-points were sustained viral response and adverse events. Data were analysed as intention to treat and as intended per protocol. RESULTS After 16 patients were enrolled, the study was terminated because of adverse events and modifications needed in the study design. Nine subjects were randomized to the 1.0 microg/kg group and seven subjects were randomized to the 0.5 microg/kg group. Serious adverse events requiring discontinuation of therapy occurred in five (56%) subjects in the 1.0 microg/kg group and in two (28%) subjects in the 0.5 microg/kg group (P = 0.36). The most common adverse events were hypertension and infection unrelated to neutropenia. Two (22%) subjects in the 1.0 microg/kg group, both genotype 1, had a sustained viral response, and none of the subjects in the 0.5 microg/kg group had a sustained viral response (P = 0.47). Five subjects in the 1.0 microg/kg group were able to complete 24 weeks or longer of therapy as per protocol and two (40%) were sustained responders. CONCLUSIONS In our study group, pegylated interferon alpha-2b was poorly tolerated and was associated with substantial side effects. Sustained response rates seen with pegylated interferon in our study do not appear to be better than rates reported for standard interferon alpha-2b.