Merck & Co. Inc. reports that grazoprevir/elbasvir, an investigational single tablet regimen for the treatment of chronic hepatitis C virus (HCV) infection, has received two new Breakthrough Therapy designations from the US Food and Drug Administration (FDA) for the treatment of patients with chronic HCV genotype 4 (GT4) infection and for the treatment of chronic HCV genotype 1 (GT1) infection in patients with end stage renal disease on hemodialysis.

In October 2013, the FDA granted Breakthrough Therapy designation for grazoprevir/elbasvir for the treatment of patients with chronic HCV genotype 1 (GT1). In January 2015, the FDA notified Merck of its intention to rescind that Breakthrough Therapy designation. The FDA has now granted two new Breakthrough Therapy designations for grazoprevir/elbasvir; the designations are now for the treatment of patients infected with chronic HCV GT1 with end-stage renal disease on hemodialysis, and patients infected with chronic HCV genotype 4 (GT4). Breakthrough Therapy designation is intended to expedite the development and review of a candidate that is planned for use, alone or in combination, to treat a serious or life-threatening disease or condition when preliminary clinical evidence indicates that the drug may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints.

Grazoprevir/elbasvir is an investigational, once-daily single tablet regimen consisting of grazoprevir (NS3/4A protease inhibitor) and elbasvir (NS5A replication complex inhibitor). As part of Merck's broad clinical trials program, grazoprevir/elbasvir is being studied in multiple HCV genotypes and in patients with difficult-to-treat conditions such as HIV/HCV co-infection, advanced chronic kidney disease, inherited blood disorders, cirrhosis, and those on opiate substitution therapy.

Source: Merck & Co.