Effectiveness of Elbasvir and Grazoprevir Combination, With or Without Ribavirin, for Treatment-Experienced Patients...

Area of Science:

• Hepatology
• Virology
• Pharmacology

Background:

• Hepatitis C virus (HCV) genotypes 1, 4, and 6 in patients previously treated with peg-interferon and ribavirin present a significant therapeutic challenge, particularly those with cirrhosis or prior treatment failure.
• Elbasvir (HCV NS5A inhibitor) and grazoprevir (HCV NS3/4A protease inhibitor) are potent antiviral agents investigated for HCV treatment.

Purpose of the Study:

• To evaluate the efficacy and safety of a fixed-dose combination of elbasvir and grazoprevir, with or without ribavirin, in patients with treatment-experienced HCV genotypes 1, 4, or 6.
• To determine the sustained virologic response rate (SVR12) at 12 or 16 weeks of treatment in this challenging patient population.

Main Methods:

• A phase 3, randomized, controlled, open-label trial involving 420 patients across 65 centers in 15 countries.
• Patients received elbasvir (50 mg) and grazoprevir (100 mg) once daily, with or without ribavirin twice daily, for 12 or 16 weeks.
• Randomization was stratified by cirrhosis status and treatment failure type; SVR12 was the primary endpoint.

Main Results:

• SVR12 rates ranged from 92.4% to 98.1% across treatment arms. Specifically, 12-week treatment yielded 92.4% (elbasvir/grazoprevir) and 94.2% (elbasvir/grazoprevir + ribavirin). 16-week treatment yielded 92.4% (elbasvir/grazoprevir) and 98.1% (elbasvir/grazoprevir + ribavirin).
• Virologic failure was low, particularly in the 16-week arm with ribavirin (0%). Higher failure rates were observed in the 12-week arm without ribavirin for specific genotypes and treatment failure types.
• Common adverse events included fatigue (23.1%), headache (19.8%), and nausea (11.0%), indicating good tolerability.

Conclusions:

• The elbasvir and grazoprevir combination tablet, with or without ribavirin, demonstrates high efficacy in achieving SVR12 in patients with previously treated HCV genotypes 1, 4, or 6, including those with cirrhosis or null response.
• The treatment regimen was generally well-tolerated, supporting its use in this difficult-to-treat population.
• ClinicalTrials.gov Identifier: NCT02105701.