TABLE 3.

Clinical trials against HCQ use. The following databases were searched: Cochrane, Embase, Medline, New England Journal of Medicine and PubMed. A total of four trials (two randomized controlled trials (RCT) and two cohort studies) showed no significant improvement in clinical outcome and mortality when comparing the HCQ-treated group to the control group.

Evidence against the use of HCQ
Study	Study type	Country	Population size	Results	Ref
A pilot study of hydroxychloroquine in treatment of patients with common coronavirus disease-19 (COVID-19)	Single-center RCT	China	30	No significant prognostic difference was noted between the HCQ-treated group and the control group.Comparable adverse events were experienced by each group. Studied outcomes included: • Time to negative conversion • time for body temperature normalization • radiological progression• adverse events experienced by both groups	(Chen J. et al., 2020)
Hydroxychloroquine in patients with mainly mild to moderate coronavirus disease 2019: Open label, randomised controlled trial	Multi-center RCT	China	150	No significant prognostic difference was noted between the HCQ-treated group and the control group. More adverse events were observed in the treated group.Studied outcomes included: • Time to negative conversion • adverse events experienced by both groups	(Tang et al., 2020)
Association of treatment with hydroxychloroquine or azithromycin with in-hospital mortality in patients with COVID-19 in New York state	Multi-center retrospective cohort study	United States, New York	1,438	There was no significant improvement in mortality rate in hospitalized COVID-19 patients treated with HCQ, azithromycin or HCQ + azithromycin. Studied outcomes included: • In-hospital mortality • incidence of fatal cardiac events	(Rosenberg et al., 2020)
Observational study of hydroxychloroquine in hospitalized patients with Covid-19	Single-center, observational study	United States, New York	1,446	The use of HCQ had no significant effect on clinical outcomes and in-hospital mortality.Studied outcomes included: • Clinical worsening (denoted by the need for intubation) • death	(Geleris et al., 2020)