An Open Label Randomized Controlled Trial of Ivermectin Plus Favipiravir-Based Standard of Care versus Favipiravir-Based Standard of Care for Treatment of Moderate COVID-19 in Thailand

Background: The role of ivermectin in the treatment of moderate coronavirus disease 2019 (COVID-19) is controversial. We performed an open label randomized controlled trial to evaluate the role of ivermectin plus favipiravir-based standard of care versus favipiravir-based standard of care for the treatment of moderate COVID-19 infection. Materials and Methods: An open-label randomized control trial was performed at Thammasat Field Hospital and Thammasat University Hospital from October 1st, 2021 to May 31st, 2022. Patients with moderate COVID-19 infections were randomized to the intervention (ivermectin plus favipiravir-based standard of care) or control group (favipiravirbased standard of care alone). Patients were followed up to 21 days. The primary outcome was the improvement in World Health Organization (WHO) category ordinal scale by 2 points. Secondary outcomes included duration of illness, development of severe COVID-19, and adverse reactions. Results: There were 157 patients in the intervention and 160 patients in the control group. Characteristics, underlying diseases, and risk factors for severe COVID-19 were comparable in both groups. Improvement in the WHO-category ordinal scale by 2 points was achieved in 98.7% of the intervention group and in 99.4% of the control group (relative risk [RR]: 0.487; 95% confidence interval [CI]: 0.044-5.430). The median illness duration was 5.0 days (range, 3 -28 days) in intervention group versus 5.2 days (range, 3 -28 days) in control group (P = 0.630). Severe COVID-19 that required intensive care occurred in 2 patients (1.3%) in the intervention group and 1 patient (0.6%) in the control group (RR: 2.052; 95% CI: 0.184 -22.857). No significant difference in serious drug adverse events was seen.