Chloroquine and hydroxychloroquine in the treatment of COVID-19: the never-ending story

Abstract

The anti-malarial drugs chloroquine (CQ) and hydroxychloroquine (HCQ) have been suggested as promising agents against the new coronavirus SARS-CoV-2 that induces COVID-19 and as a possible therapy for shortening the duration of the viral disease. The antiviral effects of CQ and HCQ have been demonstrated in vitro due to their ability to block viruses like coronavirus SARS in cell culture. CQ and HCQ have been proposed to reduce immune reactions to infectious agents, inhibit pneumonia exacerbation, and improve lung imaging investigations. CQ analogs have also revealed the anti-inflammatory and immunomodulatory effects in treating viral infections and related ailments. There was, moreover, convincing evidence from early trials in China about the efficacy of CQ and HCQ in the anti-COVID-19 procedure. Since then, research and studies have been massive to ascertain these drugs' efficacy and safety in treating the viral disease. In the present review, we construct a synopsis of the main properties and current data concerning the metabolism of CQ/HCQ, which were the basis of assessing their potential therapeutic roles against the new coronavirus infection. The effective role of QC and HCQ in the prophylaxis and therapy of COVID-19 infection is discussed in light of the latest international medical-scientific research results. Key points• Data concerning metabolism and properties of CQ/HCQ are discussed.• The efficacy of CQ/HCQ against COVID-19 has been the subject of contradictory results.• CQ/HCQ has little or no effect in reducing mortality in SARS-CoV-2-affected patients.

Epidemiological and Clinical Characteristics of COVID-19: A Retrospective Multi-Center Study in Pakistan

“…Paracetamol, chloroquine, and cetirizine were the most frequently prescribed medicines during the early days of the COVID-19 pandemic in Pakistan (71)(72)(73)(74). However, the current data is insufficient to assess the effect of medications on the outcome of the disease.…”

Opinion and uptake of chloroquine for treatment of COVID-19 during the mandatory lockdown in the sub-Saharan African region

“…37 This becomes more disturbing in Africa where many have underlying diseases they are unaware of because of poor health systems and or lack of proper screening programs. With this in mind, and in the light of recent evidence that CQ and HCQ are not effective for the treatment of COVID-19, 9 this study will guide SSA countries in formulating temporary prescription guidelines and restrictions around CQ usage. One way of doing this is through legislation of CQ/HCQ as prescription-only-medication and making it available to designated pharmacies within regions.…”

“…http://www.phcfm.org Open Access promising in vitro results, 8 there are no direct supporting data on the effective role of CQ and HCQ in the treatment of COVID-19. 9 Those reporting that the drug has a favourable effect on the outcomes of COVID-19 were not clinical trials and used poor methodology. 4,5,6,7,10 Chloroquine and its analogue, HCQ are considered safe and have side effects that are generally mild and transitory.…”

Low pH Hypromellose (Taffix™) nasal powder spray reduced SARS-CoV-2 infection rate post mass-gathering event at a highly endemic community: An observational prospective open label user survey

“…The role of Hydroxychloroquine ( HCQ) and chloroquine ( CQ) during the COVID 19 epidemic was rightly termed : "The never ending story." [18]. The antiviral effects of CQ and HCQ have been demonstrated in vitro due to their ability to block viruses like coronavirus SARS in cell culture.…”