Methods for treating treatment-naive as well as treatment-experienced adult and pediatric patients having HIV-1 infections as well as patients co-infected with HIV-1 and HCV involving administering a therapeutically effective amount of pegylated interferon-alfa, e.g., pegylated interferon alfa-2b, in association with a therapeutically effective amount of a CCR5 antagonist or preferably further in association with a therapeutically effective amount of at least one of ribavirin, IL-2, IL-12, pentafuside alone or in combination with a therapeutically effective amount of an anti-HIV-1 drug therapy, e.g., HAART are disclosed.