OBJECTIVE: To evaluate the long-term outcomes of hepatitis delta patients, including cirrhosis and hepatocellular carcinoma (HCC), based on clinical and laboratory data. METHODOLOGY: A retrospective evaluation was conducted on patients diagnosed with hepatitis delta. The patients were formed into four groups: no-treatment, pegylated interferon, oral antiviral, and combined treatment. RESULTS: A total of 93 patients, 48 women and 45 men, were evaluated in the study. The mean follow-up time was 4.38 ± 2.7 years. Of those, 43 were in the no-treatment group, 22 received combination therapy including pegylated interferon and oral antiviral treatment for chronic hepatitis B (the combined treatment group), 19 received only oral antiviral treatment for chronic hepatitis B (the oral antiviral group), and nine received pegylated interferon (the pegylated interferon group). HDV-RNA negativity was observed in 67% (6/9) of patients in the pegylated interferon group and 33% (5/15) of patients in the combined treatment group. HDV-RNA became spontaneously negative in one of the two patients in the no-treatment group, while no patient in the oral antiviral group became HDV-RNA negative. Seven patients were diagnosed with cirrhosis and one with HCC. Three patients had undergone liver transplants. There were no fatalities among patients. CONCLUSIONS: Pegylated interferon therapy has been demonstrated to have partial efficacy in the treatment of delta hepatitis, while oral antivirals have been shown to offer no additional benefit. Although negative HDV-RNA was achieved in some patients treated with pegylated interferon, pegylated interferon treatment could not eliminate the risk of cirrhosis and HCC.