Adjunctive favipiravir for severe COVID-19: A retrospective observational study of the first 41 patients in Thailand

Abstract

Background: Favipiravir is a promising drug for COVID-19, but evidence from a robust clinical trial is limited. Objective: To describe the demographics, clinical characteristics, and various antiviral treatment regimens (with and without favipiravir) of patients with severe and nonsevere COVID-19. Method: We conducted a retrospective observational study in all COVID-19 patients admitted at Bamrasnaradura Infectious Diseases Institute (BIDI) from January 8 to March 30, 2020. We compared the demographics, clinical characteristics, and various antiviral treatment regimens of 12 severe and 29 nonsevere COVID-19 patients in Thailand. Results: Adjunctive favipiravir was given to only severe cases. The median length of hospitalization of patients either receiving favipiravir or not receiving favipiravir was not significantly different (P = 0.8549), but those who received adjunctive favipiravir became reverse transcriptase-polymerase chain reaction negative 2 days sooner than the other group (median: 6 days vs. 8 days; P = 0.1125). Conclusion: The findings suggested that adjunctive favipiravir might not be effective for patients with severe COVID-19, but further studies with larger sample sizes are needed.