Sirijatuphat R.Manosuthi W.Niyomnaitham S.Owen A.Copeland K.K.Charoenpong L.Rattanasompattikul M.Mahasirimongkol S.Wichukchinda N.Chokephaibulkit K.Mahidol University2023-06-182023-06-182022-01-01Emerging Microbes and Infections Vol.11 No.1 (2022) , 2197-2206https://repository.li.mahidol.ac.th/handle/20.500.14594/85044We investigated Favipiravir (FPV) efficacy in mild cases of COVID-19 without pneumonia and its effects towards viral clearance, clinical condition, and risk of COVID-19 pneumonia development. PCR-confirmed SARS-CoV-2-infected patients without pneumonia were enrolled (2:1) within 10 days of symptomatic onset into FPV and control arms. The former received 1800 mg FPV twice-daily (BID) on Day 1 and 800 mg BID 5–14 days thereafter until negative viral detection, while the latter received only supportive care. The primary endpoint was time to clinical improvement, defined by a National Early Warning Score (NEWS) of ≤1. 62 patients (41 female) comprised the FPV arm (median age: 32 years, median BMI: 22 kg/m²) and 31 patients (19 female) comprised the control arm (median age: 28 years, median BMI: 22 kg/m²). The median time to sustained clinical improvement, by NEWS, was 2 and 14 days for FPV and control arms, respectively (adjusted hazard ratio (aHR) of 2.77, 95% CI 1.57–4.88, P <.001). The FPV arm also had significantly higher likelihoods of clinical improvement within 14 days after enrolment by NEWS (79% vs. 32% respectively, P <.001). 8 (12.9%) and 7 (22.6%) patients in FPV and control arms developed mild pneumonia at a median (range) of 6.5 (1–13) and 7 (1–13) days after treatment, respectively (P =.316). All recovered well without complications. We can conclude that early treatment of FPV in symptomatic COVID-19 patients without pneumonia was associated with faster clinical improvement. Trial registration: Thai Clinical Trials Registry identifier: TCTR20200514001.Immunology and MicrobiologyArticleSCOPUS10.1080/22221751.2022.21170922-s2.0-851384591832222175135997325