Mean changes in hepatitis C virus (HCV) RNA levels during treatment Interferon therapy is the standard of care for hepatitis C virus (HCV) infection; however, interferon must be given subcutaneously and is prone to troublesome side effects. Dr. Gane et al. at Auckland City Hospital in New Zealand evaluated the effects of sofosbuvir, an oral HCV nucleotide polymerase inhibitor drug, on treatment regimens for HCV infection without interferon or with restricted interferon. They found that sofosbuvir combined with ribavirin treatment for 12 weeks was effective in patients with previously untreated type 1, type 2, and type 3 HCV infection. The paper was published in the January 3, 2013 online edition of the leading international journal NEJM. Enrolled patients were divided into eight open-label treatment groups. A total of 40 patients with previously untreated type 2 or 3 HCV infection were randomized to 4 groups; all 4 groups received sofosbuvir treatment (dose 400 mg once daily) plus ribavirin for a total of 12 weeks. Three of the groups received pegylated interferon alfa-2a at weeks 4, 8, and 12. Two groups of previously untreated patients with type 2 or type 3 HCV infection received sofosbuvir alone for 12 weeks or sofosbuvir plus pegylated interferon alfa-2a plus ribavirin for 8 weeks. Two groups of patients with type 1 HCV infection received sofosbuvir and ribavirin for 12 weeks: 10 patients who did not respond to prior therapy and 25 previously untreated patients. The researchers reported sustained virologic response (SVR) rates at 24 weeks post-treatment. Results showed that of the 40 patients treated in the randomized group, all 10 (100%) patients treated with sofosbuvir plus ribavirin without interferon and all 30 (100%) patients treated with sofosbuvir plus ribavirin and receiving interferon at weeks 4, 8, and 12 achieved a sustained virologic response at 24 weeks. For other patients with type 2 or 3 HCV infection, all 10 (100%) patients treated with sofosbuvir plus peg interferon alfa-2a and ribavirin for 8 weeks achieved a 24-week sustained virologic response, as did 6 (60%) of such patients treated with sofosbuvir alone. The researchers found that for patients with type 1 HCV infection, 21 of 25 (84%) patients without prior therapy and 1 of 10 (10%) patients who did not respond to prior therapy achieved a sustained virologic response at 24 weeks. The most common adverse events observed in the study were headache, fatigue, insomnia, nausea, rash and anemia. The researchers concluded that sofosbuvir plus ribavirin for 12 weeks is effective in patients with previously untreated type 1, 2, and 3 HCV infection.