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. 2020 Aug 19;7(2):e001362. doi: 10.1136/openhrt-2020-001362

Table 1.

QTc prolongation and ventricular arrhythmia or mortality in trials using hydroxychloroquine (HCQ) or chloroquine (CQ) in combination with azithromycin (AZT)

Study Drug Dose Study size Outcomes
Van den Broek et al28 CQ alone 600 mg loading dose then 300 mg BD for 5 days 95

  • QTc prolonged from 444 ms to 479 ms (p<0.01)

  • QTc >500 ms in 22 patients (23.2%)

  • No ventricular arrhythmias
Borba et al11 High-dose CQ+AZT
Low-dose CQ+AZT		 600 mg BD for 10 days or
450 mg BD for 1 day then 450 mg BD for 4 days		 81

  • Increased mortality rates in high-dose group (39.0% vs 15.0%)

  • Increased rate of QTc >500 ms in high-dose group (18.9% vs 11.1%)

  • Ventricular arrhythmia in 2 patients (2.7%)
Chorin et al27 HCQ+AZT 400 mg BD for 1 day then 200 mg BD for 4 days 84

  • QTc prolonged from 435 ms to 463 ms (p<0.001)

  • QTc >500 ms in 9 patients (11%)
Saleh et al31 HCQ or CQ alone
HCQ/CQ+AZT		 HCQ: 400 mg BD for 1 day then 200 mg BD for 4 days
CQ: 500 mg BD for 1 day then 500 mg OD for 4 days		 201

  • Combination therapy associated with increased QTc prolongation (470.4±45.0 ms vs 453.3±37.0 ms, p=0.004)

  • Ventricular arrhythmia in 8 patients (4.0%)

  • 7 patients (3.5%) discontinued due to QTc prolongation
Mercuro et al29 HCQ alone
HCQ+AZT		 400 mg BD for 1 day then 400 mg OD for 4 days 90

  • Combination therapy associated with increased QTc prolongation (23 ms vs 5.5 ms; p=0.03)

  • QTc >500 ms in 18 patients (20%)

  • 1 episode of TdP

  • 10 patients (11%) discontinued due to QTc prolongation
Bessière et al26 HCQ alone
HCQ+AZT		 200 mg BD for 10 days 40

  • QTc prolonged from 414 ms to 454 ms (p<0.01)

  • QTc >500 ms in 7 patients (17.5%)

  • No ventricular arrhythmias

  • 7 patients (17.5%) discontinued due to QTc prolongation
Mahévas et al30 HCQ alone 600 mg daily 181

  • No mortality benefit of HCQ+AZT group vs no HC (10.7% vs 9.0%; HR 1.2 (0.5 to 3.0))

  • 8 patients (10%) discontinued due to QTc prolongation
Magagnoli et al12 HCQ alone
HCQ+AZT		 Details not reported 368

  • Increased mortality rates in HCQ group vs no HCQ (27.8% vs 11.4%; p=0.03)

  • No mortality benefit of HCQ+AZT group vs no HCQ (22.1% vs 11.4%; p=0.72)
Geleris et al3 HCQ alone 600 mg BD for 1 day then 400 mg OD for 4 days 1376

  • Outcome of intubation/death unchanged with HCQ (HR 1.04 (0.82 to 1.32))

BD, twice daily; OD, once daily; TdP, torsades de pointes.