New Regimen Shows Promise for HCV Genotypes 1, 2, and 3

A regimen of grazoprevir, elbasvir, and a Merck agent known as MK-3682, or a second agent called MK-8408 (or both), showed "strong results" company researchers said in data presented at the Liver Meeting (AASLD) in San Francisco, CA.

There were two triple combination regimens evaluated: a regimen of grazoprevir (100mg), MK-3682 (300mg or 450mg) and elbasvir (50mg); and a regimen of grazoprevir (100mg), MK-3682 (300mg or 450mg) and MK-8408 (60mg).

Based on the results of trials in treatment-naive patients with HCV genotypes 1, 2, or 3 infection, the company has begun a second phase of trials.

The novel triple-combination regimens showed 100% efficacy in achieving a sustained viral response at 12 weeks (SVR12) in patients with GT1 infections, regardless of which combinations of the three antivirals were given.

In GT 2 infection results varied depending on the combination and dosage, ranging from 60% to 94% of treated patients achieving that SVR12. For GT 3 infection, the SVR12 ranges were 95% to 90%. All patients had chronic HCV infection but were non-cirrhotic.

The next phase of the trials will evaluate safety and will inlcude patients with or without compensated cirhosis or with HIV/HCV co-infection. The trials will also include GT3 patients previously treated with interferon and ribavirin.

Grazoprevir is an HCV NS3/4 protease inhibitor. MK-3682 is nucleotide analogue NS5B polymerase inhibitor.” Elbasvir is an HCV NS5A replication complex inhibitor, as is MK-8408.