Safety and efficacy of Hydroxychloroquine and Chloroquine in treatment of COVID-19: A rapid review of evidence

 The corona virus disease (COVID-19) 2019 pandemic has resulted in significant morbidity and mortality around the world and led to serious challenges for health systems. To date, there are no medical treatments for COVID-19 with proven effectiveness. To treat COVID-19 patients a wide range of existing antibiotics, such as Hydroxychloroquine(HCQ) and chloroquine(CQ), have been recommended as potential treatment. This study is a rapid systematic review aimed to identify and summarize evidence on efficacy and safety of HCQ and CQ for COVID-19 infection.

 This study is a rapid systematic review that that systematically searches electronic databases including PubMed, EMBASE, ClinicalTrials.gov, Cochrane Library till 22 May 2020. Peer-reviewed Randomized clinical trials, reviews and observational studies that investigated efficacy and safety of HCQ and CQ for prevention and treatment of COVID-19 infection were included. Other types of studies, including case reports, physician's opinion, commentaries and letter to the editors were excluded.

 There were 7 review articles, five clinical trial studies, and 8 observational studies focusing on CQ or HCQ to treat COVID-19 patients. Of five clinical trial included, three showed favorable outcomes among patients received CQ or HCQ. One of them reported no change compared to control group. Another one suggested that high doses of CQ especially in combination with other drugs such as Azithromycin and Oselatamivir should not be recommended for older patients due to risks associated with its safety. Eight observational studies were included in our review, of which 4 studies concluded that there is no difference between the use of HCQ or combination of HCQ and Azithromycin with other medications. Three studies showed that administration of a combination of HCQ and Azithromycin or HCQ alone is associated with improved clinical outcomes. One study investigated the side effects associated with administration of HCQ and azithromycin together. It concluded that the combination of HCQ and Azithromycin significantly prolongs the QT interval in patients with COVID-19.

The included studies reported conflicting results on the efficacy and safety HCQ and CQ in treating COVID-19. Therefore, it seems there are not sufficient evidence about the effectiveness and safety of HCQ and CQ to treat patients with COVID-19 and more studies, which also report long-term follow up results, are needed.