Study: Oral Hepatitis Drugs Achieve High Cure Rates
Sustained virologic response seen in 100% of patients (November 2)
Positive data have been reported from the ongoing C-WORTHY study, a phase II clinical trial evaluating the efficacy and safety of an all-oral regimen combining once-daily MK-5172 (an investigational hepatitis C virus [HCV] NS3/4A protease inhibitor) and MK-8742 (an investigational HCV NS5A replication complex inhibitor) (Merck), with or without twice-daily ribavirin, administered for 12 weeks to treatment-naïve, non-cirrhotic patients with HCV genotype 1a and 1b infection.
The new data show that the combination of MK-5172 and MK-8742 was associated with a sustained virologic response (i.e., a lack of detectable and quantifiable HCV) 12 weeks after the end of study therapy (SVR12).
The FDA has granted a “breakthrough therapy” designation to MK-5172/MK-8742 for the treatment of chronic HCV infection.
In the C-WORTHY study, 65 patients (45% male, 11% African-American, and 58% with genotype 1a infection) were enrolled in one of three 12-week treatment arms: 1) MK-5172 (100 mg) + MK-8742 (20 mg) + ribavirin; 2) MK-5172 (100 mg) + MK-8742 (50 mg) + ribavirin; or 3) MK-5172 (100 mg) + MK-8742 (50 mg). The virologic response was assessed each week during treatment and at 2, 4, 8, 12, and 24 weeks after the end of treatment. The trial’s primary efficacy endpoint was the proportion of patients who achieved a sustained virologic response at post-treatment follow-up week 12 (SVR12).
SVR12 was achieved in 100% (21/21) of the group treated with MK-5172 (100 mg) + MK-8742 (20 mg) + ribavirin; in 96% (23/24) of the group treated with MK-5172 (100 mg) + MK-8742 (50 mg) + ribavirin; and in 100% (11/11) of the group treated with MK-5172 (100 mg) + MK-8742.
In the entire study population, one patient (1.5%) experienced a relapse with detectable HCV RNA at follow-up weeks 4 and 12.
Source: Merck; November 2, 2013.