Background and Aim: Ropeginterferon alfa-2b is a novel mono-pegylated, extra-long-acting interferon. It is administered infrequently and showed good tolerability and clinical activity for the chronic hepatitis B or C treatment in our previous Phase 2 clinical trials. This study aims to validate the potency and safety of this novel agent in a Phase 3 chronic viral hepatitis setting. Methods: Patients with chronic hepatitis C genotype 2 were randomized to receive subcutaneous injections of ropeginterferon alfa-2b biweekly or the conventional pegylated interferon alfa-2b weekly for 24 weeks, combined with ribavirin. The primary endpoint was to assess the safety and antiviral potency of ropeginterferon alfa-2b by the non-inferiority in sustained virologic response at 12 weeks after treatment. Results: A total of 222 patients were enrolled. Ropeginterferon alfa-2b group showed a favorable safety profile. Side effects that were generally associated with prior interferon therapies, including neutropenia, asthenia, fatigue, alopecia, dizziness, decreased appetite, nausea, flu-like symptoms including myalgia, pyrexia, and headache, and administration site reactions, were notably less in the ropeginterferon alfa-2b group. The cumulative incidence of adverse events of special interest was also notably higher in the control group. The primary endpoint was met and ropeginterferon alfa-2b showed a better SVR12 rate of 79.8% than 71.9% of the control group. Conclusion: Ropeginterferon alfa-2b is efficacious and has a favorable safety profile as compared with the conventional pegylated interferon alfa-2b. This study together with previous Phase 2 data validated ropeginterferon alfa-2b to be a new treatment option for chronic hepatitis C genotype 2.