Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Jul;28(7-8):406-409.
doi: 10.1007/s12471-020-01429-7.

Chloroquine-induced QTc prolongation in COVID-19 patients

M P H van den Broek  1 , J E Möhlmann  2 , B G S Abeln  3 , M Liebregts  3 , V F van Dijk  3 , E M W van de Garde  2   4
Affiliations

Chloroquine-induced QTc prolongation in COVID-19 patients

M P H van den Broek et al. Neth Heart J. 2020 Jul.

Abstract

Background: In the battle against the SARS-CoV‑2 pandemic, chloroquine has emerged as a new potential therapeutic option for the treatment of infected patients. A safety consideration for the application of chloroquine is its QTc-prolonging potential. Thus far, no data are available on the QTc-prolonging potential of chloroquine in COVID-19 patients.

Objective: To assess the degree of chloroquine-induced QTc prolongation in hospitalised COVID-19 patients.

Methods: A baseline electrocardiogram (ECG) and ECGs recorded during chloroquine treatment were retrospectively collected in patients suspected of having COVID-19. The QTc interval was calculated by computerised and manual interpretation. Baseline and follow-up QTc intervals were compared using the paired samples t-test.

Results: A total of 95 patients had a baseline ECG recording and at least one ECG recording during chloroquine therapy. Chloroquine treatment resulted in a mean QTc prolongation of 35 ms (95% CI 28-43 ms) using computerised interpretation and 34 ms (95% CI 25-43 ms) using manual interpretation. No torsade de pointes was observed during chloroquine treatment. After manual review, 22 patients (23%) had a QTc interval exceeding 500 ms during chloroquine treatment. None of these patients had a prolonged QTc interval prior to the initiation of chloroquine treatment.

Conclusions: Chloroquine significantly prolongs the QTc interval in a clinically relevant matter. This highlights the need for ECG monitoring when prescribing chloroquine to COVID-19 patients.

Keywords: COVID-19; Chloroquine; Coronavirus; Electrocardiogram; QT prolongation; SARS-CoV‑2.

PubMed Disclaimer

Conflict of interest statement

M.P.H. van den Broek, J.E. Möhlmann, B.G.S. Abeln, M. Liebregts, V.F. van Dijk and E.M.W. van de Garde declare that they have no competing interests.

Figures

Fig. 1
Fig. 1
Distribution of PR, QRS and QTc intervals before and during chloroquine treatment after computerised ECG interpretation (left box before chloroquine treatment, right box during chloroquine treatment)
See this image and copyright information in PMC

References

    1. Wang M, Cao R, Zhang L, et al. Remdesivir and chloroquine effectively inhibit the recently emerged novel coronavirus (2019-nCoV) in vitro. Cell Res. 2020;30:269–271. doi: 10.1038/s41422-020-0282-0. - DOI - PMC - PubMed
    1. Mzayek F, Deng H, Mather FJ, et al. Randomized dose-ranging controlled trial of AQ-13, a candidate antimalarial, and chloroquine in healthy volunteers. PLoS Clin Trials. 2007;2:e6. doi: 10.1371/journal.pctr.0020006. - DOI - PMC - PubMed
    1. Pukrittayakamee S, Tarning J, Jittamala P, et al. Pharmacokinetic interactions between primaquine and chloroquine. Antimicrob Agents Chemother. 2014;58:3354–3359. doi: 10.1128/AAC.02794-13. - DOI - PMC - PubMed
    1. Ursing J, Rombo L, Eksborg S, et al. High-dose chloroquine for uncomplicated Plasmodium falciparum malaria is well tolerated and causes similar QT interval prolongation as standard-dose chloroquine in children. Antimicrob Agents Chemother. 2020;64:1–12. doi: 10.1128/AAC.01846-19. - DOI - PMC - PubMed
    1. Traebert M, Dumotier B, Meister L, et al. Inhibition of hERG K+ currents by antimalarial drugs in stably transfected HEK293 cells. Eur J Pharmacol. 2004;484:41–48. doi: 10.1016/j.ejphar.2003.11.003. - DOI - PubMed

LinkOut - more resources