BILN-2016

BILN-2016 is a small molecule inhibitor of the Hepatitis C Virus (HCV) NS3/4A serine protease, developed by Boehringer Ingelheim. It was one of the early lead compounds in the research program that eventually produced BILN-2061 (ciluprevir), the first NS3 protease inhibitor to demonstrate antiviral activity in humans. BILN-2016 is a linear peptidomimetic that targets the substrate-binding site of the NS3 protease, an enzyme essential for the cleavage of the HCV polyprotein into mature non-structural proteins required for viral replication. Although BILN-2016 showed significant potency in vitro, the program shifted focus toward macrocyclic analogs like BILN-2061 to improve pharmacological properties and binding affinity. Development of the entire chemical series was eventually halted due to observations of myocardial toxicity in animal studies, which precluded further clinical advancement of these specific candidates.