Disclosed are combination pharmaceutical agents for the treatment of an HCV infection comprising a compound effective to inhibit the function of the HCV NS5A protein and another compound having anti-HCV activity. Compounds which can inhibit the function of the NS5A protein having the structure of formula I are described wherein R, R′, R1, R2, and R3 are as defined in the specification. The other compounds having anti-HCV activity are effective to inhibit the function of a target selected from the group consisting of HCV metalloprotease, HCV serine protease, HCV polymerase, HCV helicase, HCV NS4B protein, HCV entry, HCV assembly, HCV egress, HCV NS5A protein, IMPDH and a nucleoside analog for the treatment of an HCV infection.