Over two years into the pandemic, global collaboration led to effective antiviral drugs targeting SARS-CoV-2's RdRp and 3CL protease. However, the virus continues to evolve, and certain low-virulence variants still circulate. Despite reduced virulence, ongoing transmission raises the risk of new mutations, underscoring the need for continued vigilance, research, and expansion of our antiviral and vaccine strategies. Our research team has developed SHEN26, a promising small-molecule antiviral drug for the treatment of COVID-19. This mini-review explores its development, including history, synthesis, preclinical evaluations, and findings from Phase I and II clinical trials. Data from each research phase further underscores SHEN26's potential as a safe and effective oral antiviral treatment for COVID-19, while also emphasizing its broader relevance in combating emerging RNA viral infections.