Aspects of this invention include methods comprising administering a combination of a Compound (1) below, including particular en crystalline forms thereof and pharmaceutically acceptable salts thereof, with at least one further selected HCV inhibiting compound as described herein for the treatment of Hepatitis C Viral (HCV) infection The methods can be conducted administering the Compound (1) and the at least one further selected HCV inhibiting compound separately or together, including as a regimen of treatment.