BACKGROUND: A novel antiviral agent, remdesivir (RDV), is a promising candidate treatment for coronavirus disease 2019 (COVID-19) in the absence of any proven therapy. MATERIALS AND METHODS: This retrospective case series included 10 patients with a clinically and laboratory confirmed diagnosis of severe COVID-19 pneumonia who had received RDV for 5 days (n = 5) or 10 days (n = 5) in the Phase III clinical trial of RDV (GS-US-540-5773) conducted by Gilead Sciences. The clinical and laboratory data for these patients were extracted. RESULTS: One patient in the 10-day group received RDV for only 5 days because of nausea and elevated liver transaminases. No patient had respiratory comorbidity. Seven patients had bilateral lesions and three had unilateral lesions on imaging. All patients had received other medications for COVID-19, including lopinavir/ritonavir and hydroxychloroquine, before administration of RDV. Five patients required supplemental oxygen and one required mechanical ventilation. All patients showed clinical and laboratory evidence of improvement. Half of the patients developed elevated liver transaminases and three had nausea. There were no adverse events exceeding grade 2. CONCLUSION: Our experience indicates that RDV could be a therapeutic option for COVID-19. A well-designed randomized controlled clinical trial is now needed to confirm the efficacy of RDV in patients with COVID-19.