Annals of Clinical Cardiology

: 2020  |  Volume : 2  |  Issue : 1  |  Page : 47--48

Chloroquine for coronavirus disease 2019 (COVID-19)?

Suman Omana Soman1, Muneer Abdul Rahaman2,  
1 Department of Cardiology, Badr Al Samaa Hospital, Barka, Oman
2 Department of Cardiology, KIMS Hospital, Trivandrum, Kerala, India

Correspondence Address:
Dr. Suman Omana Soman
Simi Bhavan, Azhoor P O, Thiruvananthapuram, Kerala

How to cite this article:
Soman SO, Rahaman MA. Chloroquine for coronavirus disease 2019 (COVID-19)?.Ann Clin Cardiol 2020;2:47-48

How to cite this URL:
Soman SO, Rahaman MA. Chloroquine for coronavirus disease 2019 (COVID-19)?. Ann Clin Cardiol [serial online] 2020 [cited 2022 Dec 6 ];2:47-48
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Full Text

Dear Editor,

A new coronavirus (CoV) that previously has not been identified in humans emerged in Wuhan, China, in December 2019. The Chinese Center for Disease Control and Prevention wing declared that the etiology of this pneumonia is due to a virus belonging to the CoV family.[1] In the beginning of 2020 (February 11), the World Health Organization (WHO) director general announced that the disease is caused by new novel beta-CoV (coronavirus disease 2019 [COVID-19]).[2] It started in Wuhan, China, and spread to 196 countries. According to the WHO as of April 2020, there are more than 29,00,000 confirmed cases of COVID-19 infection, including more than 200000 deaths. Higher mortality rate were among patients with co morbiditie.[3]

Currently, there is no specific antiviral therapy recommended for this infection, and vaccine development is on the way of processing. The use of antiviral drugs, lopinavir and ritonavir, is found to be beneficial in patients with severe acute respiratory syndrome-CoV and Middle East respiratory syndrome (MERS)-CoV.[4],[5],[6] One more study in the Middle East showed the efficiency by the use of combination therapy with interferon beta-1b, lopinavir, and ritonavir among patients with MERS infection.[7]

Chloroquine is a member of the drug class 4-aminoquinoline,[8] which acts by inhibiting heme polymerase, primarily used to treat malarial infections. The antiviral effects of chloroquine are by the increase of late endosomal and lysosomal pH, which may affect the release of these viruses as they require a low pH. Thus, chloroquine prevents the replication of the viruses by inhibiting the release of genetic material to the cell. The use of chloroquine can help reduce the viral load in patients.[9],[10]

Literature reveals the antiviral effect of chloroquine.[11] Reports from China show the efficacy and safety of the use of chloroquine in the treatment of patients who suffered from COVID-19-associated pneumonia in multicentric clinical trials, which include a study population of more than 100 patients.[12],[13] A combination therapy by remdesivir and chloroquine was found to be effective in preventing the replication of the novel CoV in China during the outbreak in 2019.[14] Philippe Gautret et al. reported that the combination of chloroquine with azithromycin has an additional benefit when compared to single therapy with chloroquine.[15]

The study populations were small, so we need more randomized controlled studies to prove the efficacy and safety of the drug in COVID-19 patients. However, chloroquine may be considered for the treatment of patients with COVID-19 in view of no effective treatment currently available for this disease. Patients require proper monitoring before and during the treatment including QT interval by electrocardiogram to avoid ventricular arrhythmias.

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Conflicts of interest

There are no conflicts of interest.


1Cascella M, Rajnik M, Cuomo A, Dulebohn SC, Di Napoli R. Features, Evaluation and Treatment Coronavirus (COVID-19). Treasure Island (FL): StatPearls Publishing; 2020. [Last update on 2020 Mar 20]. PMID: 32150360.
2Schlitzer M. Malaria chemotherapeutics part I: history of antimalarial drug development, currently used therapeutics, and drugs in clinical development. Chem MedChem 2007;2:944-86.
3Rajan R, Jarallah MA, Dashti R. Cardiovascular complications of novel Wuhan Coronavirus (COVID-19) – A 2020 update. J Cardiol Curr Res 2020;13:28.
4Chu CM. Role of lopinavir/ritonavir in the treatment of SARS: Initial virological and clinical findings. Thora×2004;59:252-6.
5Sheahan TP, Sims AC, Graham RL, Menachery VD, Gralinski LE, Case JB, et al. Broad-spectrum antiviral GS-5734 inhibits both epidemic and zoonotic coronaviruses. Sci Transl Med 2017;9. pii: eaal3653.
6Sheahan TP, Sims AC, Leist SR, Schäfer A, Won J, Brown AJ, et al. Comparative therapeutic efficacy of remdesivir and combination lopinavir, ritonavir, and interferon beta against MERS-CoV. Nat Commun 2020;11:222.
7Arabi YM, Alothman A, Balkhy HH, Al-Dawood A, AlJohani S, Al Harbi S, et al. Treatment of Middle East respiratory syndrome with a combination of lopinavir-ritonavir and interferon-β1b (MIRACLE trial): Study protocol for a randomized controlled trial. Trials 2018;19:81.
8Phosphate A. The American Society of Health-System Pharmacists; 8 December 2015. [Last retrieved on 2015 Dec 02]. PMID: 15364632.
9Al-Bari MA. Targeting endosomal acidification by chloroquine analogs as a promising strategy for the treatment of emerging viral diseases. Pharmacol Res Perspect 2017;5:e00293.
10Fredericksen BL, Wei BL, Yao J, Luo T, Garcia JV. Inhibition of endosomal/lysosomal degradation increases the infectivity of human immunodeficiency virus. J Virol 2002;76:11440-6.
11Savarino A, Boelaert JR, Cassone A, Majori G, Cauda R. Effects of chloroquine on viral infections: an old drug against today's diseases? Lancet Infect Dis 2003;3:722-7.
12Cortegiani A, Ingoglia G, Ippolito M, Giarratano A, Einav S. A systematic review on the efficacy and safety of chloroquine for the treatment of COVID-19. J Critical Care 2020. pii: S0883-9441 (20) 30390-7.
13Gao J, Tian Z, Yang X. Breakthrough: Chloroquine phosphate has shown apparent efficacy in treatment of COVID-19 associated pneumonia in clinical studies. Biosci Trends 2020;14:72-3.
14Agostini ML, Andres EL, Sims AC, Graham RL, Sheahan TP, Lu X, et al. Coronavirus susceptibility to the antiviral remdesivir (GS-5734) is mediated by the viral polymerase and the proofreading exoribonuclease. mBio 2018;9. pii: e00221-18.
15Gautret P, Lagier JC, Parola P, Hoang VT, Meddeb L, Mailhe M, et al. Hydroxychloroquine and azithromycin as a treatment of COVID-19: Results of an open-label non-randomized clinical trial. Int J Antimicrob Agents 2020;105949.