We assessed the efficacy and safety of ledipasvir/sofosbuvir plus ribavirin for 24 weeks in 9 human immunodeficiency virus/hepatitis C virus-coinfected patients who relapsed after receiving 12 weeks of treatment with ledipasvir/sofosbuvir. Eight of 9 (89%) achieved sustained virologic response 12 weeks after the end of treatment. One patient relapsed at posttreatment week 4. These results suggest an effective salvage therapy for patients for whom direct-acting antiviral treatment has failed. Clinical Trials Registration. NCT02073656.