Background The sustained virological response (SVR) rate for the 12-week sofosbuvir (SOF)/ledipasvir (LVD) treatment of adolescent genotype-4 patients is high. The aim of this study is to evaluate 8 versus 12-week treatment efficacy and safety in adolescent genotype-4 patients. Patients and methods In total, 157 chronic hepatitis C-infected adolescent patients (mean age 14±2 years, 62% males) were included in this study. All patients received a morning dose of SOF (400 mg)/LVD (90 mg) as a single tablet for 8 and 12 weeks. Laboratory and biochemical monitoring were performed at weeks 4 and 8, end of treatment (8/12) and 12 weeks after the end of treatment (SVR12). Results In total, SVR12 was 98% [95% confidence interval (CI): 96–100] for all treated patients. For patients treated for 12 weeks, SVR12 was 97.6% (95% CI: 96–101) (82/84 patients), and 98.6% (95% CI: 93–101) (72/73) patients for those treated for 8 weeks. For both regimens, no serious adverse effects, treatment discontinuation or cases of death were detected. The main adverse effects for the 8-week patient group were fatigue (2.8%), headache (1.4%), nausea (1.4%) and epigastric tenderness (1.4%). For the 12-week-treated group, adverse events were epigastric tenderness (1.2%), nausea (1.2%), diarrhoea (2.4%) and rash (2.4%). Three patients were lost to follow-up: two were in the 12-week treatment group and one was in the 8-week group. All of them reached end of treatment but were lost before SVR12. No relapsers were observed in either group. Conclusion Eight weeks of treatment of SOF/LVD combination is equally effective and safe as 12 weeks in adolescent genotype-4 patients.

Summary Direct‐acting antivirals have become available for treating chronic HCV (hepatitis C virus) infection in adults and, recently, in children at least 12 years old. Our aim was to investigate the safety and efficacy of combined sofosbuvir (SOF)/daclatasvir (DCV) for HCV Genotype 4 in children aged 8 to 18 years or weighing 17 kg or more. A total of 40 chronic HCV‐infected, treatment‐naïve children with well compensated livers were recruited from two sites. Patients received combined therapy of SOF (400 mg/d for patients weighing greater than 45 kg; 200 mg/d for patients weighing 17 to 45 kg) and DCV (60 mg/d for patients weighing greater than 45 kg; 30 mg/d for patients weighing 17 to 45 kg) for 12 weeks. They were followed up regularly by clinical examination and laboratory tests during treatment (weekly in the first month then monthly to the end of treatment), every 3 months for 6 months post‐treatment, and at 48 weeks post‐treatment. In our cohort, which included 45% of children below the age of 12 years (72.5% genotype 4 and 27.5% mixed genotype 4 and 1), end of treatment response (ETR) was 97.5%. Sustained virologic response for weeks 12 and 24 post‐treatment (SVR12 and SVR24) were 97.5% and 95%, respectively, on an intention to treat basis, and 100% and 100% for those who completed the study protocol. Observed side effects were mild and none required drug cessation. Combined SOF/DCV was found to be effective and safe for treating HCV Genotype 4‐infected children, 8 years of age and above.