Between Aug 14 , 2012 , and Nov 19 , 2013 , 467 patients with HCV infection were screened , of whom 174 were infected with genotype 4.135 patients were randomly assigned to treatment and received at least one dose of study medication ; 86 patients were treatment-naive , of whom 44 received ombitasvir plus paritaprevir plus ritonavir and 42 received ombitasvir plus paritaprevir plus ritonavir with ribavirin , and 49 treatment-experienced patients received the ribavirin-containing regimen .