Table 1.
Selected randomized controlled trials comparing the efficacy of hydroxychloroquine and control group(s).
| Randomized Controlled Trials | Patient Characteristics | Comparison groups | Number of patients included | Primary Outcome Measure | Main results |
|---|---|---|---|---|---|
| Recovery Collaborative Group, Horby P et al. [12] | Hospitalized patients with COVID-19 | Hydroxychloroquine vs. usual care | 1561 vs. 3155 | 28-day mortality | 27% vs. 25%; RR: 1.09; 95% CI, 0.97–1.23; p: 0.15 |
| WHO Solidarity Trial, Pan et al. [13] | Hospitalized patients with COVID-19 | Hydroxychloroquine vs. local standard of care | 947 vs. 906 | 28-day mortality | 10.9% vs. 9.3%; RR: 1.19; 95% CI, 0.89–1.59; p: 0.23 |
| Cavalcanti et al. [14] | Hospitalized patients with suspected or confirmed COVID-19 who were receiving either no oxygen or a maximum of 4 lt/min of supplemental oxygen | Standard care vs. standard care+ hydroxychloroquine vs. standard care+ hydroxychloroquine+ azithromycin | 229 vs. 221 vs. 217 | Having a higher score on the seven-point ordinal scale at 15 days | Hydroxychloroquine plus azithromycin vs. control, OR: 0.99; 95% CI, 0.57–1.73; p: 1.00; hydroxychloroquine alone vs. control: OR: 1.21; 95% CI, 0.69–2.11; p: 1.00 and hydroxychloroquine plus azithromycin vs. hydroxychloroquine alone: OR: 0.82; 95% CI, 0.47–1.43; p: 1.00 |
| Self et al. [15] | Adults hospitalized with symptomatic SARS-CoV-2 infection | Hydroxychloroquine vs. placebo | 242 vs. 237 | Clinical status at 14 days according to seven-level ordinal scale | Median IQR score, 6 (4–7) vs. 6 (4–7); aOR: 1.02; 95% CI, 0.73–1.42 |
| Tang et al. [16] | Patients admitted to hospital with laboratory confirmed COVID-19 | Hydroxychloroquine+ standard of care vs. standard of care | 75 vs. 75 | Negative conversion of SARS-CoV-2 by 28 days | 85.4% vs. 81.3%; the difference: 4.1%; 95% CI, −10.3% to 18.5% |
| Furtado et al. [17] | Suspected or confirmed severe COVID-19 patients | Azithromycin+ standard of care vs. standard of care* | 214 vs. 183 | Clinical status at 15 days according to seven-level ordinal scale | OR: 1.36; 95% CI, 0.94–1.97; p: 0.11 |
| Boulware et al. [18] | Adults who had household or occupational exposure to someone with confirmed COVID-19 | Hydroxychloroquine vs. placebo | 414 vs. 407 | Incidence of either laboratory-confirmed COVID-19 or illness compatible with COVID-19 within 14 days | 11.8% vs. 14.3%; the difference: −2.4%; 95% CI, −7% to 2.2%; p: 0.35 |
| Abella et al. [19] | Health care workers caring for patients with COVID-19 | Hydroxychloroquine vs. placebo | 64 vs. 61 | Incidence of SARS-CoV-2 infection as determined by a nasopharyngeal swab during the 8 weeks of treatment. | 6.3% vs. 6.6%; p: >0.99 |
| Mitjà et al. [20] | Asymptomatic contacts of patients with PCR–confirmed COVID-19 | Hydroxychloroquine vs. usual care | 1116 vs. 1198 | Incidence of PCR-confirmed, symptomatic COVID-19 within 14 days | 5.7% vs. 6.2%; RR: 0.86; 95% CI, 0.52–1.42 |
Abbreviations: COVID-19, coronavirus diseases 2019; RR, rate ratio; OR, odds ratio; aOR, adjusted odds ratio; CI, confidence interval; PCR, polymerized chain reaction; SARS-CoV-2, Severe Acute Respiratory Syndrome Coronavirus-2; lt, liter; min, minute.
*
All patients received hydroxychloroquine as a part of standard of care.