Source Department of Hepatology and Gastroenterology, Hôpital Henri Mondor, Université Paris-Est, Créteil, France; INSERM U955, Créteil, France.
COMMENTARY ON:: Oral combination therapy with a nucleoside polymerase inhibitor (RG7128) and danoprevir for chronic hepatitis C genotype 1 infection (INFORM-1): A randomised, double-blind, placebo-controlled, dose-escalation trial. Gane EJ, Roberts SK, Stedman CA, Angus PW, Ritchie B, Elston R, Ipe D, Morcos PN, Baher L, Najera I, Chu T, Lopatin U, Berrey MM, Bradford W, Laughlin M, Shulman NS, Smith PF. Lancet 2010 Oct 30;376(9751):1467-75. Reprinted from The Lancet, Copyright (2010), with permission from Elsevier. http://www.ncbi.nlm.nih.gov/pubmed/20951424
BACKGROUND: Present interferon-based standard of care treatment for chronic hepatitis C virus (HCV) infection is limited by both efficacy and tolerability. We assessed the safety, tolerability, and antiviral activity of an all-oral combination treatment with two experimental anti-HCV drugs-RG7128, a nucleoside polymerase inhibitor; and danoprevir, an NS3/4A protease inhibitor-in patients with chronic HCV infection
METHODS: Patients from six centres in New Zealand and Australia who were chronically infected with HCV genotype 1 received up to 13days oral combination treatment with RG7128 (500 or 1000mg twice daily) and danoprevir (100 or 200mg every 8h or 600 or 900mg twice daily) or placebo. Eligible patients were sequentially enrolled into one of seven treatment cohorts and were randomly assigned by interactive voice or web response system to either active treatment or placebo. Patients were separately randomly assigned within each cohort with a block size that reflected the number of patients in the cohort and the ratio of treatment to placebo. The random allocation schedule was computer generated. Dose escalation was started in HCV treatment-naive patients; standard of care treatment-experienced patients, including previous null responders, were enrolled in higher-dose danoprevir cohorts. Investigators, personnel at the study centre, and patients were masked to treatment allocation. However, the pharmacist who prepared the doses, personnel involved in pharmacokinetic sample analyses, statisticians who prepared data summaries, and the clinical pharmacologists who reviewed the data before deciding to initiate dosing in the next cohort were not masked to treatment allocation. The primary outcome was change in HCV RNA concentration from baseline to day 14 in patients who received 13days of combination treatment. All patients who completed treatment with the study drugs were included in the analyses. This study is registered with ClinicalTrials.gov., NCT00801255.
FINDINGS: Eighty-eight patients were randomly assigned to a study drug treatment regimen (n=74 over seven treatment groups; 73 received at least one dose of study drug) or to placebo (n=14, all of whom received at least one dose). The median change in HCV RNA concentration from baseline to day 14 ranged from -3.7 to -5.2 log(10)IU/ml in the cohorts that received 13days of combination treatment. At the highest combination doses tested (1000mg RG7128 and 900mg danoprevir twice daily), the median change in HCV RNA concentration from baseline to day 14 was -5.1 log(10)IU/ml (IQR-5.6 to -4.7) in treatment-naive patients and -4.9 log(10)IU/ml in previous standard of care null responders (-5.2 to -4.5) compared with an increase of 0.1 log(10)IU/ml in the placebo group. The combination of RG7128 and danoprevir was well tolerated with no treatment-related serious or severe adverse events, no grade 3 or 4 changes in laboratory parameters, and no safety-related treatment discontinuations.
INTERPRETATION: This oral combination of a nucleoside analogue polymerase inhibitor and protease inhibitor holds promise as an interferon-free treatment for chronic HCV.