March 28, 2012 (New York, New York) — In vitro data on a next-generation hepatitis C virus (HCV) NS3/4A protease inhibitor garnered considerable interest here at the International Conference on Viral Hepatitis 2012.
MK-5172, being developed by Merck & Co, demonstrated "potent activity" against the majority of primary first-generation protease inhibitor resistance-associated variants (RAVs) in biochemical and cell-based phenotype assays, reported Richard J. Barnard, PhD, from Merck & Co.
MK-5172 also inhibited patient-derived NS3 proteases across HCV genotypes and retained activity against HCV proteases isolated from 5 patients with vaniprevir RAVs.
In his presentation, Dr. Barnard noted that virologic failure with first-generation protease inhibitors is often associated with the emergence of RAVs; it is important that next-generation molecules are pangenotypic and active against first-generation protease inhibitor RAVs. "MK-5172 fulfills the profile expected of a next-generation" HCV protease inhibitor, he said.
Douglas T. Dieterich, MD, professor of medicine from the division of liver diseases at Mount Sinai School of Medicine in New York City, who was not involved in the study, told Medscape Medical News that "MK-5172 represents a promising potential best-in-class second-generation protease inhibitor."
"MK-5172 is a truly second-generation protease inhibitor," he explained. "This is really good news for the people who have already failed treatment with a first-generation protease inhibitor."
MK-5172, Dr. Dieterich said, "has activity against the most common resistance mutations caused by telaprevir and boceprevir. Even more encouraging for global use, it is active against genotypes 1, 2, 4, 5, and 6."
Dr. Barnard reports being an employee of Merck & Co and owning stock in the company. Dr. Dieterich reports financial relationships with Bristol-Myers Squibb, Gilead Sciences, Roche Laboratories, and Boehringer Ingelheim.
International Conference on Viral Hepatitis (ICVH) 2012: Oral Abstract: 79340. Presented March 26, 2012.