Paritaprevir (ABT450) is a potent small molecule inhibitor targeting the HCV NS3/4A serine protease. It demonstrates high antiviral activity with EC50 values of 1 nM against HCV genotype 1a and 0.21 nM against genotype 1b. This compound is a key research tool for studying HCV replication and antiviral mechanisms in biochemical and cellular assays.