Real-world Safety and Effectiveness of 24-week Sofosbuvir and Ribavirin Treatment in Patients Infected with Rare Chronic Hepatitis C Virus Genotypes 3, 4, 5, or 6 in Japan

OBJECTIVES: Real-world evidence on the safety and effectiveness of direct-acting antivirals in patients infected with chronic hepatitis C virus (HCV) genotypes (GTs) 3, 4, 5, or 6 in Japan is limited. This prospective observational study assesses the real-world safety profile and treatment effectiveness among patients prescribed sofosbuvir with ribavirin (SOF+RBV) for HCV GT3-6 infection in Japan. METHODS: Adults receiving 24-week SOF+RBV treatment for HCV GT3-6 infection were prospectively enrolled and observed through 24 weeks post-treatment for treatment-emergent adverse events (AEs) considered related to SOF and/or RBV by treating physicians and for a sustained virologic response at 12 and 24 weeks post-treatment (SVR12, SVR24). Incidence rates of related AEs and serious AEs (SAEs) were calculated. Proportions of patients experiencing related AEs/SAEs and those achieving SVR12 and SVR24 were assessed overall and by baseline characteristics, including treatment experience and cirrhosis status. RESULTS: Among the 50 patients included in the safety analysis, 92% had GT3 infection. The incidence rates of related AEs and SAEs were low overall (1.52 and 0.25 per 100 person-weeks, respectively), with 6.0% and 14.0% patients experiencing AEs related to SOF or RBV, respectively. There were no marked differences in the occurrence of related AEs/SAEs by patient baseline characteristics. SVR12 and SVR24 were achieved in 83.7% (41/49) and 82.2% (37/45) of patients, respectively. Lower effectiveness was observed among treatment-experienced patients and patients with cirrhosis at baseline. CONCLUSION: This study demonstrated that SOF+RBV treatment for HCV GT3-6 infection was safe, effective, and an important treatment option for this difficult-to-treat patient population in Japan.