{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T22:34:42Z","timestamp":1778798082722,"version":"3.51.4"},"reference-count":30,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,2,17]],"date-time":"2021-02-17T00:00:00Z","timestamp":1613520000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Science and Technology","award":["MOST 108-2221-E-037-003"],"award-info":[{"award-number":["MOST 108-2221-E-037-003"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Chloroquine (CQ) and its derivative, hydroxychloroquine (HCQ), have attracted wide attention for treating coronavirus disease 2019 (COVID-19). However, conflicting outcomes have been found in COVID-19 clinical trials after treatment with CQ or HCQ. To date, it remains uncertain whether CQ and HCQ are beneficial antiviral drugs for combating COVID-19. We performed a systematic review to depict the efficacy of CQ or HCQ for the treatment of COVID-19. The guidelines of PRISMA were used to conduct this systematic review. We searched through articles from PubMed, Web of Science and other sources that were published from 1 January 2020 to 31 October 2020. The search terms included combinations of human COVID-19, CQ, and HCQ. Eleven qualitative articles comprising of four clinical trials and seven observation studies were utilized in our systematic review. The analysis shows that CQ and HCQ do not have efficacy in treatment of patients with severe COVID-19. In addition, CQ and HCQ have caused life-threatening adverse reactions which included cardiac arrest, electrocardiogram modification, and QTc prolongation, particularly during the treatment of patients with severe COVID-19. Our systematic review suggested that CQ and HCQ are not beneficial antiviral drugs for curing patients with severe COVID-19. The treatment effect of CQ and HCQ is not only null but also causes serious side effects, which may cause potential cardiotoxicity in severe COVID-19 patients.<\/jats:p>","DOI":"10.3390\/pathogens10020217","type":"journal-article","created":{"date-parts":[[2021,2,17]],"date-time":"2021-02-17T21:35:42Z","timestamp":1613597742000},"page":"217","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":27,"title":["Chloroquine and Hydroxychloroquine: Efficacy in the Treatment of the COVID-19"],"prefix":"10.3390","volume":"10","author":[{"given":"Tzu-Chuan","family":"Ho","sequence":"first","affiliation":[{"name":"Department of Medical Imaging and Radiological Sciences, Kaohsiung Medical University, Kaohsiung 807, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yung-Hsuan","family":"Wang","sequence":"additional","affiliation":[{"name":"St. Dominic Catholic High School, Kaohsiung 802, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yi-Ling","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Nuclear Medicine, Kaohsiung Medical University Hospital, Kaohsiung 807, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4490-3581","authenticated-orcid":false,"given":"Wan-Chi","family":"Tsai","sequence":"additional","affiliation":[{"name":"Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 807, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8543-3862","authenticated-orcid":false,"given":"Che-Hsin","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Biological Science, National Sun Yat-sen University, Kaohsiung 804, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kuo-Pin","family":"Chuang","sequence":"additional","affiliation":[{"name":"Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung 912, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yi-Ming Arthur","family":"Chen","sequence":"additional","affiliation":[{"name":"Graduate Institute of Biomedical and Pharmaceutical Science, Fu Jen Catholic University, New Taipei City 242, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cheng-Hui","family":"Yuan","sequence":"additional","affiliation":[{"name":"Mass Spectrometry Laboratory, Department of Chemistry, National University of Singapore, Singapore 119077, Singapore"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3997-6575","authenticated-orcid":false,"given":"Sheng-Yow","family":"Ho","sequence":"additional","affiliation":[{"name":"Department of Radiation Oncology, Chi Mei Medical Center, Graduate Institute of Medical Science, Chang Jung Christian University, Tainan 710, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5856-0498","authenticated-orcid":false,"given":"Ming-Hui","family":"Yang","sequence":"additional","affiliation":[{"name":"Department of Medical Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung 813, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1917-5893","authenticated-orcid":false,"given":"Yu-Chang","family":"Tyan","sequence":"additional","affiliation":[{"name":"Department of Medical Imaging and Radiological Sciences, Kaohsiung Medical University, Kaohsiung 807, Taiwan"},{"name":"Graduate Institute of Animal Vaccine Technology, College of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung 912, Taiwan"},{"name":"Neuroscience Research Center, Graduate Institute of Medicine, College of Medicine, Center for Cancer Research, Research Center for Environmental Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,2,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1953","DOI":"10.1056\/NEJMoa030781","article-title":"A Novel Coronavirus Associated with Severe Acute Respiratory Syndrome","volume":"348","author":"Ksiazek","year":"2003","journal-title":"N. 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