Treatment Response to Hydroxychloroquine and Antibiotics for mild to moderate COVID-19: a retrospective cohort study from South Korea

Objectives: To assess the efficacy of hydroxychloroquine on mild-moderate COVID-19 patients in South Korea. Methods: A retrospective cohort study of the 358 laboratory-confirmed SARS-CoV-2 (COVID-19) patients was conducted. 226 patients met inclusion criteria for analysis. Propensity score matching (PSM) and Cox regression method were utilized to control and adjust for confounding factors. Mild to moderate COVID-19 patients were managed with hydroxychloroquine (HQ) plus antibiotics (n = 31) or conservative treatment (n = 195). Results: Kaplan-Meier curves drawn using propensity score-matched data revealed no differences between the length of time to viral clearance and duration of hospital stay between the two treatment arms (p=0.18, p=0.088). Multivariable Cox regression analysis similarly showed that time to viral clearance(Hazard ratio (HR) 0.97, [95%-confidence interval (CI): 0.57-1.67]) and symptom duration(HR 1.05, [95%-CI: 0.62-1.78]) were not different between groups. No severe adverse event or death was observed in either group. Conclusions: HQ with antibiotics was not associated with better clinical outcomes in terms of time to viral clearance, length of hospital stay, and duration of symptoms compared to conservative treatment alone. Large prospective randomized trials are necessary for definitive conclusions.