This paper analyzed clinical studies, systematic reviews and clinical practice guidelines on the treatment of COVID-19 with antiviral drugs. It elaborated on the evidence ecosystems in these studies following the "efficacy, evidence-based practice, effectiveness" (3E) model that considered five elements: research hypothesis, research evidence, big data from healthcare facilities, real-world data, and real-world evidence. Finally, this paper summarized the experience in the production, transformation and application of evidence. This paper could help clinicians conduct high-quality clinical research and provide good clinical practice based on the best currently available evidence.