Advances in the use of chloroquine and hydroxychloroquine for the treatment of COVID-19

ABSTRACT

Coronavirus Disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is spreading worldwide. Antiviral therapy is the most important treatment for COVID-19. Among the drugs under investigation, anti-malarials, chloroquine (CQ) and hydroxychloroquine (HCQ), are being repurposed as treatment for COVID-19. CQ/HCQ were shown to prevent receptor recognition by coronaviruses, inhibit endosome acidification, which interferes with membrane fusion, and exhibit immunomodulatory activity. These multiple mechanisms may work together to exert a therapeutic effect on COVID-19. A number of in vitro studies revealed inhibitory effects of CQ/HCQ on various coronaviruses, including SARS-CoV-2 although conflicting results exist. Several clinical studies showed that CQ/HCQ alone or in combination with a macrolide may alleviate the clinical symptoms of COVID-19, promote viral conversion, and delay disease progression, with less serious adverse effects. However, recent studies indicated that the use of CQ/HCQ, alone or in combination with a macrolide, did not show any favorable effect on patients with COVID-19. Adverse effects, including prolonged QT interval after taking CQ/HCQ, may develop in COVID-19 patients. Therefore, current data are not sufficient enough to support the use of CQ/HCQ as therapies for COVID-19 and increasing caution should be taken about the application of CQ/HCQ in COVID-19 before conclusive findings are obtained by well-designed, multi-center, randomized, controlled studies.

KEYWORDS:

• Coronavirus
• sars-CoV-2
• chloroquine
• hydroxychloroquine
• antiviral

Acknowledgments

We are very grateful to Dr. Adam Kim from Cleveland Clinic for the English language editing of our manuscript.

Declaration of financial/other relationships

The authors have no financial or other relationships to disclose.

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Author contributions

JKS and ZWL wrote the article, and contributed to the concept of this article, definition of intellectual content, and data acquisition; YTC, XDF, XYW contributed to data acquisition; QYH reviewed the manuscript for its intellectual content.

Declaration of interest

No potential conflict of interest was reported by the authors.

Additional information

Funding

This manuscript received no funding.