Data regarding the nephrotoxicity of sofosbuvir (SOF) remain controversial. The investigators compared the changes of estimated glomerular filtration rate (eGFR) in patients with chronic hepatitis C virus (HCV) infection receiving SOF-based or SOF-free direct acting antivirals (DAAs).

Chronic hepatitis C virus (HCV) infection is a major health problem that affects 71 million people worldwide. Patients with chronic HCV infection may present with various hepatic and extrahepatic manifestations which lead to substantial morbidity and mortality. In contrast, the long-term health outcome improves following successful HCV eradication by antiviral therapies.

Owing to the excellent efficacy and safety as well as the short treatment duration, the use of interferon (IFN)-free direct acting antivirals (DAAs) has become the standard-of-care for managing HCV. Sofosbuvir (SOF) is a pyrimidine nucleotide analogue which acts as the HCV ribonucleic acid (RNA) chain terminator by inhibiting HCV non-structural protein 5B (NS5B) RNA-dependent RNA polymerase following intrahepatic activation to uridine triphosphate form. Dephosphorylation results in the formation of inactive metabolite (GS-331007) that undergoes extensive renal excretion. Clinically, SOF is administered once-daily with pangenotypic potency, well tolerability and a high genetic barrier to drug resistance. Furthermore, SOF can be used in combination with NS3/4A protease inhibitors (PIs), NS5A inhibitors, and/or ribavirin (RBV) to achieve high rates of sustained virologic response (SVR). Therefore, applying SOF-based DAAs for HCV is welcome to most treating physicians.

Following the widespread use of SOF-based DAAs for treating HCV in different populations, a large-scale real-world HCV-TARGET study enrolling 1,789 patients indicated that patients with a baseline eGFR ≤ 45 mL/min/1.73m2 were associated with a higher risk of worsening renal function than those with a baseline eGFR > 45 mL/min/1.73m2 following SOF-based DAAs. Moreover, three retrospective studies showed that SOF-based DAAs negatively affected the on-treatment and off-therapy eGFR. On the contrary, other studies showed that the use of SOF-based DAAs did not worsen the eGFR. Because most studies were retrospective in nature without protocol-defined time point for eGFR assessment or patient election, and did not enroll patients receiving SOF-free DAAs as the controls, the investigators thus conducted a prospective study to evaluate the evolution of eGFR in patients with chronic HCV infection receiving SOF-based or SOF-free DAAs.

Inclusion Criteria:

• Chronic HCV patients receiving SOF-based or SOF-free DAAs for 12 weeks

Exclusion Criteria:

• Decompensated cirrhosis (Child-Pugh B or C)
• Estimated glomerular filtration rate (eGFR) < 30 mL/min/1.73m2
• Active hepatocellular carcinoma (HCC)
• Organ transplantation
• Hepatitis B virus (HBV) co-infection
• Human immunodeficiency virus (HIV) co-infection
• Not received off-therapy follow-up till week 24

Chronic hepatitis C virus-infected patients with compensated liver diseases and baseline eGFR of 30 mL/min/1.73m2 or more, who received SOF-based or SOF-free DAAs for 12 weeks, and who received off-therapy follow-up until week 24