Patients were randomly assigned in a 2:1:2:1 ratio to receive 150 mg simeprevir and 400 mg sofosbuvir daily for 24 weeks with ( group 1 ) or without ( group 2 ) ribavirin or for 12 weeks with ( group 3 ) or without ( group 4 ) ribavirin , in two cohorts : previous non-responders with METAVIR scores F0-F2 ( cohort 1 ) and previous non-responders and treatment-naive patients with METAVIR scores F3-F4 ( cohort 2 ) .