SVR12 was achieved in all 171 ( 100 % ) patients ( 83 of 83 treatment naive and 88 of 88 treatment experienced ) receiving ledipasvir-sofosbuvir ( 95 % CI 98-100 ) and 167 ( 98 % ) of 170 patients ( 80 of 83 treatment naive and 87 of 87 treatment experienced ) receiving ledipasvir-sofosbuvir plus ribavirin ( 95 % CI 95-100 ) .