what evidence is there for the value of hydroxychloroquine in treating Covid-19?

Chloroquine and hydroxychloroquine in the management of COVID-19: much kerfuffle but little evidence

Summary Chloroquine and hydroxychloroquine are drugs that have shown in vitro activity on the replication of certain coronaviruses. In the context of the SARS-Cov-2 epidemic, the virus responsible for the novel coronavirus disease (COVID-19), these two drugs have been proposed as possible treatments. The results of the first clinical studies evaluating the effect of hydroxychloroquine do not support any efficacy of this drug in patients with COVID-19, due to major methodological weaknesses. Yet, these preliminary studies have aroused considerable media interest, raising fears of massive and uncontrolled use. In the absence of evidence of clinical benefits, the main risk is of exposing patients unnecessarily to the well-known adverse effects of hydroxychloroquine, with a possibly increased risk in the specific setting of COVID-19. In addition, widespread use outside of any recommendation risks compromising the completion of good quality clinical trials. The chloroquine hype, fueled by low-quality studies and media announcements, has yielded to the implementation of more than 150 studies worldwide. This represents a waste of resources and a loss of opportunity for other drugs to be properly evaluated. In the context of emergency, rigorous trials are more than ever needed in order to have, as soon as possible, reliable data on drugs that are possibly effective against the disease. Meanwhile, serious adverse drug reactions have been reported in patients with COVID-19 receiving hydroxychloroquine, justifying to limit its prescription, and to perform suitable cardiac and therapeutic drug monitoring.

Chloroquine and hydroxychloroquine in the management of COVID-19: Much kerfuffle but little evidence

Reasonable Doubt: Hydroxychloroquine Studies for COVID-19 Are Methodological Garbage

Lack of efficacy of hydroxychloroquine in covid-19.

Pharmacokinetic bases of the hydroxychloroquine response in COVID-19: implications for therapy and prevention

Chloroquine/hydroxychloroquine has recently been the subject of intense debate in regard to its potential antiviral activity against SARS-Cov-2, the etiological agent of COVID-19. Some report possible curative effects, others do not. In order to shed some light on this rather controversial topic, we used mathematical modelling to simulate possible scenarios of response to hydroxychloroquine in COVID-19 patients. Our computer-aided simulations show that hydroxychloroquine may have an impact on the amplitude of the viral load peak but that viral clearance is not significantly accelerated if the drug is not administered early enough (i.e. when viral loads range from 1 to 1,000 copies/mL). Although some authors had used the trough plasma concentrations or the theoretical drug distribution in the lung to model the effect of chloroquine/hydroxychloroquine on COVID-19, the theoretical drug response based on the trough whole blood concentrations of the drug agreed well with the results of the clinical trials so far reported. Moreover, the effects of chloroquine/hydroxychloroquine could be fully explained when taking into account also the capacity of this drug to raise cell-mediated responses against the productively SARS-Cov-2-infected cells. On the whole, the present study suggests that chloroquine/hydroxychloroquine has a narrow therapeutic window, which overlaps with the highest tolerated doses. These considerations may have implications for development of anti-COVID-19 combination therapies and prevention strategies.

Effect of Hydroxychloroquine in Hospitalized Patients with COVID-19: Preliminary results from a multi-centre, randomized, controlled trial.

Background: Hydroxychloroquine and chloroquine have been proposed as treatments for coronavirus disease 2019 (COVID-19) on the basis of in vitro activity, uncontrolled data, and small randomized studies. Methods: The Randomised Evaluation of COVID-19 therapy (RECOVERY) trial is a randomized, controlled, open-label, platform trial comparing a range of possible treatments with usual care in patients hospitalized with COVID-19. We report the preliminary results for the comparison of hydroxychloroquine vs. usual care alone. The primary outcome was 28-day mortality. Results: 1561 patients randomly allocated to receive hydroxychloroquine were compared with 3155 patients concurrently allocated to usual care. Overall, 418 (26.8%) patients allocated hydroxychloroquine and 788 (25.0%) patients allocated usual care died within 28 days (rate ratio 1.09; 95% confidence interval [CI] 0.96 to 1.23; P=0.18). Consistent results were seen in all pre-specified subgroups of patients. Patients allocated to hydroxychloroquine were less likely to be discharged from hospital alive within 28 days (60.3% vs. 62.8%; rate ratio 0.92; 95% CI 0.85-0.99) and those not on invasive mechanical ventilation at baseline were more likely to reach the composite endpoint of invasive mechanical ventilation or death (29.8% vs. 26.5%; risk ratio 1.12; 95% CI 1.01-1.25). There was no excess of new major cardiac arrhythmia. Conclusions: In patients hospitalized with COVID-19, hydroxychloroquine was not associated with reductions in 28-day mortality but was associated with an increased length of hospital stay and increased risk of progressing to invasive mechanical ventilation or death.

Efficacy of chloroquine and hydroxychloroquine in the treatment of COVID-19

OBJECTIVE: The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also called COVID-19, has caused a pandemic which has swiftly involved the entire world and raised great public health concerns. The scientific community is actively exploring treatments that would potentially be effective in combating COVID-19. Hydroxychloroquine has been demonstrated to limit the replication of SARS-CoV-2 virus in vitro. In malarial pandemic countries, chloroquine is widely used to treat malaria. In malarial non-pandemic nations, chloroquine is not widely used. Chloroquine and hydroxychloroquine share similar chemical structures and mechanisms of action. The aim of this study was to indirectly investigate the efficacy of chloroquine and hydroxychloroquine for the treatment of COVID-19 by determining the prevalence of COVID-19 in malaria pandemic and non-pandemic nations. We sought evidence to support or refute the hypothesis that these drugs could show efficacy in the treatment of COVID-19. MATERIALS AND METHODS: We reviewed in vitro studies, in vivo studies, original studies, clinical trials, and consensus reports, that were conducted to evaluate the antiviral activities of chloroquine and hydroxychloroquine. The studies on "COVID-19 and its allied treatment were found from World Health Organization (WHO), ISI-Web of Science, PubMed, EMBASE, Scopus, Google Scholar, and clinical trial registries. The search was based on keywords: antiviral drugs, chloroquine, hydroxychloroquine, COVID-19, COVID-19 treatment modalities, and coronavirus. In addition, we analyzed the prevalence of COVID-19 in malaria pandemic and non-pandemic countries. The review and analyses were performed on March 28, 2020. RESULTS: For this study, we identified a total of 09 published articles: 03 clinical trials with sample size 150; 03 in vitro studies and 03 expert consensus reports. These studies were all suggestive that chloroquine and hydroxychloroquine can successfully treat COVID-19 infections. We found that COVID-19 infections are highly pandemic in countries where malaria is least pandemic and are least pandemic in nations where malaria is highly pandemic. CONCLUSIONS: Chloroquine and hydroxychloroquine have antiviral characteristics in vitro. The findings support the hypothesis that these drugs have efficacy in the treatment of COVID-19. People are currently using these drugs for malaria. It is reasonable, given the hypothetical benefit of these two drugs, that they are now being tested in clinical trials to assess their effectiveness to combat this global health crisis.

Therapeutic use of chloroquine and hydroxychloroquine in COVID-19 and other viral infections: A narrative review

The rapidly spreading Coronavirus Disease (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus (SARS-CoV-2), represents an unprecedented serious challenge to the global public health community. The extremely rapid international spread of the disease with significant morbidity and mortality made finding possible therapeutic interventions a global priority. While approved specific antiviral drugs against SARS-CoV-2 are still lacking, a large number of existing drugs are being explored as a possible treatment for COVID-19 infected patients. Recent publications have re-examined the use of Chloroquine (CQ) and/or Hydroxychloroquine (HCQ) as a potential therapeutic option for these patients. In an attempt to explore the evidence that supports their use in COVID-19 patients, we comprehensively reviewed the previous studies which used CQ or HCQ as an antiviral treatment. Both CQ and HCQ demonstrated promising in vitro results, however, such data have not yet been translated into meaningful in vivo studies. While few clinical trials have suggested some beneficial effects of CQ and HCQ in COVID-19 patients, most of the reported data are still preliminary. Given the current uncertainty, it is worth being mindful of the potential risks and strictly rationalise the use of these drugs in COVID-19 patients until further high quality randomized clinical trials are available to clarify their role in the treatment or prevention of COVID-19.

A Rapid Systematic Review of Clinical Trials Utilizing Chloroquine and Hydroxychloroquine as a Treatment for COVID-19

OBJECTIVES: The emergence of SARS-CoV-2 has presented clinicians with a difficult therapeutic dilemma. With supportive care as the current mainstay of treatment, the fatality rate of COVID-19 is 6.9%. There are currently several trials assessing the efficacy of different antivirals as treatment. Of these, chloroquine (CQ) and its derivative hydroxychloroquine (HCQ) have garnered the most attention. METHODS: In this study, the literature currently available on CQ and HCQ as treatment of COVID-19 was surveyed using EMBASE, PubMed, Cochrane Library, MedRxiv, and one clinical trial registry. Upon gathering published and preprint trials, risk of bias was assessed using Cochrane Risk of Bias Tool 2.0. RESULTS: There are currently seven completed clinical trials and 29 registered clinical trials focusing on HCQ or CQ as a therapeutic avenue for COVID-19. Of these, five of seven trials have shown favorable outcomes for patients using CQ or HCQ and two of seven have shown no change compared to control. However, all seven trials carried varying degrees of bias and poor study design. CONCLUSION: There are currently not enough data available to support the routine use of HCQ and CQ as therapies for COVID-19. Pending further results from more extensive studies with more stringent study parameters, clinicians should defer from routine use of HCQ and CQ. There are several clinical trials currently under way with results expected soon.

The Risks of Prescribing Hydroxychloroquine for Treatment of COVID-19-First, Do No Harm.

Efficacy of chloroquine and hydroxychloroquine in the treatment of COVID-19.

OBJECTIVE The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), also called COVID-19, has caused a pandemic which has swiftly involved the entire world and raised great public health concerns. The scientific community is actively exploring treatments that would potentially be effective in combating COVID-19. Hydroxychloroquine has been demonstrated to limit the replication of SARS-CoV-2 virus in vitro. In malarial pandemic countries, chloroquine is widely used to treat malaria. In malarial non-pandemic nations, chloroquine is not widely used. Chloroquine and hydroxychloroquine share similar chemical structures and mechanisms of action. The aim of this study was to indirectly investigate the efficacy of chloroquine and hydroxychloroquine for the treatment of COVID-19 by determining the prevalence of COVID-19 in malaria pandemic and non-pandemic nations. We sought evidence to support or refute the hypothesis that these drugs could show efficacy in the treatment of COVID-19. MATERIALS AND METHODS We reviewed in vitro studies, in vivo studies, original studies, clinical trials, and consensus reports, that were conducted to evaluate the antiviral activities of chloroquine and hydroxychloroquine. The studies on "COVID-19 and its allied treatment were found from World Health Organization (WHO), ISI-Web of Science, PubMed, EMBASE, Scopus, Google Scholar, and clinical trial registries. The search was based on keywords: antiviral drugs, chloroquine, hydroxychloroquine, COVID-19, COVID-19 treatment modalities, and coronavirus. In addition, we analyzed the prevalence of COVID-19 in malaria pandemic and non-pandemic countries. The review and analyses were performed on March 28, 2020. RESULTS For this study, we identified a total of 09 published articles: 03 clinical trials with sample size 150; 03 in vitro studies and 03 expert consensus reports. These studies were all suggestive that chloroquine and hydroxychloroquine can successfully treat COVID-19 infections. We found that COVID-19 infections are highly pandemic in countries where malaria is least pandemic and are least pandemic in nations where malaria is highly pandemic. CONCLUSIONS Chloroquine and hydroxychloroquine have antiviral characteristics in vitro. The findings support the hypothesis that these drugs have efficacy in the treatment of COVID-19. People are currently using these drugs for malaria. It is reasonable, given the hypothetical benefit of these two drugs, that they are now being tested in clinical trials to assess their effectiveness to combat this global health crisis.

Lack of efficacy of hydroxychloroquine in covid-19

Role of Chloroquine and Hydroxychloroquine in the Treatment of COVID-19 Infection- A Systematic Literature Review

Background: Coronavirus pandemic is currently a global public health emergency. At present, no pharmacological treatment is known to treat this condition, and there is a need to review the available treatments. Objective: While there have been studies to describe the role of chloroquine and hydroxychloroquine in various viral conditions, there is limited information about the use of them in COVID-19. This systematic review aims to summarize the available evidence regarding the role of chloroquine in treating coronavirus infection. Methods: The preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines were used for this review. A literature search was performed using PUBMED & Google Scholar to find articles about the role of CQ in COVID-19 patients. Results: We included 19 publications (Five published articles, three letters/correspondence, one commentary, five pre-proofs of accepted articles, one abstract of yet to be published article, and four were pre-prints (not yet peer-reviewed) articles) in this systematic review. All the articles mentioned about the role of chloroquine and /or hydroxychloroquine in limiting the infection with SARS-CoV-2 (the virus causing COVID-19). Conclusions: There is theoretical, experimental, preclinical and clinical evidence of the effectiveness of chloroquine in patients affected with COVID-19. There is adequate evidence of drug safety from the long-time clinical use of chloroquine and hydroxychloroquine in other indications. More data from ongoing and future trials will add more insight into the role of chloroquine and hydroxychloroquine in COVID-19 infection.

COVID-19 research has overall low methodological quality thus far: case in point for chloroquine/hydroxychloroquine

What is new? KEY FINDINGS: Clinical decision-makers must be informed by the best, most trustworthy, highest-quality, robust evidence. This translates into how much confidence we can have in the research findings and thus be optimally informed for decision-making. The estimates of effect in clinical research depends on the underlying research methodology. COVID-19 disease is presenting global health systems, clinicians, and patients grave challenges. No treatment or prophylaxis currently exists for COVID-19. The overall body of COVID-19 research is very flawed methodologically. An examination of hydroxychloroquine-azithromycin research findings due to the recent media focus revealed very low-quality methodology underpins the research. Vast amounts of time and resources are being allocated to COVID-19 research, and being potentially squandered. WHAT THIS ADDS TO WHAT WAS KNOWN: Flawed methodology and sub-optimal reporting of research findings could lead to biased estimates of effect. This could lead to treatment decisions that are not optimal based on biased estimates which could harm the patient. This article provides specific suggestions for improving on the COVID-19 methods and reporting with a focus on the issues that researchers must consider in their methodology and reporting if we are to have confidence in the estimates of effect. Failure to consider harms in research could be detrimental to the patient. This article focuses on the potential harms when therapeutic agents such as hydroxychloroquine, are being considered. WHAT IS THE IMPLICATION AND WHAT SHOULD CHANGE NOW: Research thus far on finding an optimal therapeutic agent (s) for COVID-19 could be hampered by methodologically flawed research. COVID-19 researchers must immediately and acutely focus on improving their methodology and reporting.

Efficacy and safety of chloroquine or hydroxychloroquine in moderate type of COVID-19: a prospective open-label randomized controlled study

The outbreak of novel coronavirus disease 2019 (COVID-19) has become a pandemic. Drug repurposing may represent a rapid way to fill the urgent need for effective treatment. We evaluated the clinical utility of chloroquine and hydroxychloroquine in treating COVID-19. Forty-eight patients with moderate COVID-19 were randomized to oral treatment with chloroquine (1000 mg QD on Day 1, then 500 mg QD for 9 days; n=18), hydroxychloroquine (200 mg BID for 10 days; n=18), or control treatment (n=12). Adverse events were mild, except for one case of Grade 2 ALT elevation. Adverse events were more commonly observed in the chloroquine group (44.44%) and the hydroxychloroquine group (50.00%) than in the control group (16.67%). The chloroquine group achieved shorter time to clinical recovery (TTCR) than the control group (P=0.019). There was a trend toward reduced TTCR in the hydroxychloroquine group (P=0.049). The time to reach viral RNA negativity was significantly faster in the chloroquine group and the hydroxychloroquine group than in the control group (P=0.006 and P=0.010, respectively). The median numbers of days to reach RNA negativity in the chloroquine, hydroxychloroquine, and control groups was 2.5 (IQR: 2.0-3.8) days, 2.0 (IQR: 2.0-3.5) days, and 7.0 (IQR: 3.0-10.0) days, respectively. The chloroquine and hydroxychloroquine groups also showed trends toward improvement in the duration of hospitalization and findings on lung computerized tomography (CT). This study provides evidence that (hydroxy)chloroquine may be used effectively in treating moderate COVID-19 and supports larger trials.

Abstract The rapidly spreading Coronavirus Disease (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus (SARS-CoV-2), represents an unprecedented serious challenge to the global public health community. The extremely rapid international spread of the disease with significant morbidity and mortality made finding possible therapeutic interventions a global priority. While approved specific antiviral drugs against SARS-CoV-2 are still lacking, a large number of existing drugs are being explored as a possible treatment for COVID-19 infected patients. Recent publications have re-examined the use of Chloroquine (CQ) and/or Hydroxychloroquine (HCQ) as a potential therapeutic option for these patients. In an attempt to explore the evidence that supports their use in COVID-19 patients, we comprehensively reviewed the previous studies which used CQ or HCQ as an antiviral treatment. Both CQ and HCQ demonstrated promising in vitro results, however, such data have not yet been translated into meaningful in vivo studies. While few clinical trials have suggested some beneficial effects of CQ and HCQ in COVID-19 patients, most of the reported data are still preliminary. Given the current uncertainty, it is worth being mindful of the potential risks and strictly rational the use of these drugs in COVID-19 patients until further high quality randomized clinical trials are available to clarify their role in the treatment or prevention of COVID-19.

An independent appraisal and re-analysis of hydroxychloroquine treatment trial for COVID-19.

The Risks of Prescribing Hydroxychloroquine for Treatment of COVID-19-First, Do No Harm

Treating COVID-19 with Chloroquine

Systematic Review and Meta-analysis of the Effectiveness and Safety of Hydroxychloroquine in COVID-19.

Backgrounds. Since COVID-19 outbreak, various agents have been tested but no proven effective therapies have been identified. This has led to a lot of controversies among associated researches. Hence, in order to address the issue of using hydroxychloroquine in treating COVID-19 patients, we conducted a systematic review and meta-analysis. Methods. A thorough search was carried out to find relevant studies in MEDLINE, medRxiv, PubMed, Cochrane Database, China Academic Journals Full-text Database and Web of Science. Two investigators independently reviewed 274 abstracts and 23 articles. The trials which evaluated hydroxychloroquine for treatment of COVID-19 were included for this systematic review. Two investigators assessed quality of the studies and data extraction was done by one reviewer and cross checked by the other. Results. Five trials involving 677 patients were included while conducting the meta-analysis. Compared with the control group, hydroxychloroquine with or without azithromycin showed benefits in positive-to-negative conversion of SARS-CoV-2 (odds ratio [OR], 1.95 [95% CI,0.19 to 19.73] and a reduction in progression rate (OR, 0.89 [95% CI, 0.58 to 1.37]), but without demonstrating any statistical significance. This systematic review has also suggested a possible synergistic effect of the combination therapy which included hydroxychloroquine and azithromycin. However, the use of hydroxychloroquine alone was associated with increased mortality in COVID-19 patients. Conclusion. The use of hydroxychloroquine with or without azithromycin for treatment of COVID-19 patients, seems to be effective. The combination of hydroxychloroquine and azithromycin has shown synergic effects. However, mortality rate was increased when the treatment was conducted with hydroxychloroquine.

Do we have enough evidence to use chloroquine/hydroxychloroquine as a public health panacea for COVID-19?

Hydroxychloroquine and Covid-19: A Cellular and Molecular Biology Based Update

As the time for finding a definitive and safe cure as a vaccine for novel Corona Virus Disease 2019 (Covid-19) is still far, there is need to study in depth about the other potential drugs, which can save millions of lives due to Covid-19 pandemic. Right at the center of the debate is the use of drug “Hydroxychloroquine” as a prophylaxis as well as a treatment strategy against Covid-19 in conjunction with azithromycin. In this review, we will study the cellular and molecular aspects of hydroxychloroquine, which had driven its use in Covid-19 patients, as well as its chemistry and pharmacokinetics along with clinical trials going on worldwide using hydroxychloroquine against Covid-19. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s12291-020-00900-x) contains supplementary material, which is available to authorized users.

Risks of chloroquine or hydroxychloroquine use for COVID-19

The ICMR bulletin on targeted hydroxychloroquine prophylaxis for Covid-19: Need to interpret with caution

The National Task Force for Covid-19 of the Indian Council of Medical Research (ICMR) in a bulletin dated March 21, 2020 recommended the use of hydroxychloroquine for prophylaxis in asymptomatic health care workers caring for suspected or confirmed patients and household contacts of confirmed patients. This is cause for concern with regard to bioethics and good clinical practice. The evidence for the efficacy of chloroquine and hydroxychloroquine is currently derived from open label trials and cell culture studies with no conclusive evidence available from randomised clinical trials. Hydroxychloroquine also carries contraindications in the case of conditions such as maculopathy, retinopathy and QTc prolongation and should be used with caution in vulnerable populations such as children, pregnancy, lactation and the elderly. Despite this, there has been a rush to procure and self-medicate with hydroxychloroquine, which has been addressed by the National Task Force. The WHO and the FDA have not found adequate evidence to recommend any specific medication for the treatment of Covid-19. While further evidence is awaited, including from trials registered with the FDA and the ICMR, it is recommended that the administration of hydroxychloroquine for chemo-prophylaxis be considered on a case by case basis with monitoring by a registered medical practitioner including electrocardiography (ECG). The potential for retinal and cardiac toxicity must also be borne in mind. It is further recommended that a public advisory regarding the need for caution in chemo-prophylaxis be made available in the public domain. Keywords: Coronavirus, Covid-19, SARS-CoV-2, hydroxychloroquine, chloroquine, chemoprophylaxis, bioethics, evidence- based medicine.

Chloroquine and hydroxychloroquine in covid-19.

Should chloroquine and hydroxychloroquine be used to treat COVID-19? A rapid review

BACKGROUND: On the 11 March 2020, the World Health Organization (WHO) declared that COVID-19 was a pandemic. To date, there are no medical treatments for COVID-19 with proven effectiveness. Novel treatments and/or vaccines will take time to be developed and distributed to patients. In light of this, there has been growing interest in the use of existing medications, such as chloroquine (CQ) and hydroxychloroquine (HCQ), as potential treatments of this disease. AIM: To establish the current evidence for the effectiveness of CQ and HCQ in treating COVID-19. DESIGN & SETTING: A rapid review of the literature was conducted. METHOD: Electronic searches in PubMed and Google Scholar were conducted on 21 March 2020. A further search was conducted in Google for relevant literature on 28 March 2020. RESULTS: There is limited evidence of in vitro activity of CQ/HCQ against SARS-CoV-2. A number of in vivo clinical trials are underway. The empirical data available from two of these trials reveal conflicting results. Both trials are characterised by small numbers of participants (n = 30 and n = 36) and suffer methodological limitations. No medium or long-term follow-up data is available. CONCLUSION: At present, there is insufficient evidence to determine whether CQ/HCQ are safe and effective treatments for COVID-19. High quality, adequately powered randomised clinical trials in primary and secondary care settings are urgently required to guide policymakers and clinicians. These studies should report medium- and long-term follow-up results, and safety data.

Chloroquine and hydroxychloroquine in the context of COVID-19

Chloroquine and closely related structural analogs, employed initially for the treatment of malaria, are now gaining worldwide attention due to the rapidly spreading pandemic caused by severe acute respiratory syndrome-coronavirus-2, named coronavirus disease (COVID) of 2019 (COVID-19). Although much of this attention has a mechanistic basis, the hard efficacy data for chloroquine/hydroxychloroquine in the management of the clinical syndrome of COVID-19 have been limited thus far. This review aims to present the available in vitro and clinical data for the role of chloroquine/hydroxychloroquine in COVID-19 and attempts to put them into perspective, especially in relation to the different risks/benefits particular to each patient who may require treatment.

Covid-19: six million doses of hydroxychloroquine donated to US despite lack of evidence.

[Pharmacological characteristics of chloroquine and suggestions for its use in treatment of coronavirus disease 2019 (COVID-19)].

A novel coronavirus disease (COVID-19) was identified in Wuhan City, Hubei Province of China by the end of 2019, and then, the disease spread across China and became a global pandemic. Nevertheless, there are no effective treatments or vaccines for COVID-19 until now. In addition to the treatment of patients with COVID-19, the China Medical Treatment Expert Group for COVID-19 is active to study and screen effective antiviral drugs, and has found that chloroquine, an old antimalarial,shows activity against SARS-CoV-2. Then, chloroquine was included in the Guidelines for the Diagnosis and Treatment of COVID-19 in China (version 6) issued by National Health Commission of the People's Republic of China. Currently, chloroquine phosphate and hydroxychloroquine sulfate, two chloroquine derivatives, are under clinical use. Although these two agents exhibit similar mechanisms of drug actions, there is a difference between these two chemicals in terms of target populations, therapeutic efficacy and adverse reactions. This paper summarizes the currently available data and experiences from clinical treatment for malaria with chloroquine drugs, so as to provide insights into the more rational use of chloroquine agents for the treatment of COVID-19.

The ICMR bulletin on targeted hydroxychloroquine prophylaxis for Covid-19: Need to interpret with caution.

Rethinking the role of hydroxychloroquine in the treatment of COVID-19

There are currently no proven or approved treatments for coronavirus disease 2019 (COVID-19). Early anecdotal reports and limited in vitro data led to the significant uptake of hydroxychloroquine (HCQ), and to lesser extent chloroquine (CQ), for many patients with this disease. As an increasing number of patients with COVID-19 are treated with these agents and more evidence accumulates, there continues to be no high-quality clinical data showing a clear benefit of these agents for this disease. Moreover, these agents have the potential to cause harm, including a broad range of adverse events including serious cardiac side effects when combined with other agents. In addition, the known and potent immunomodulatory effects of these agents which support their use in the treatment of auto-immune conditions, and provided a component in the original rationale for their use in patients with COVID-19, may, in fact, undermine their utility in the context of the treatment of this respiratory viral infection. Specifically, the impact of HCQ on cytokine production and suppression of antigen presentation may have immunologic consequences that hamper innate and adaptive antiviral immune responses for patients with COVID-19. Similarly, the reported in vitro inhibition of viral proliferation is largely derived from the blockade of viral fusion that initiates infection rather than the direct inhibition of viral replication as seen with nucleoside/tide analogs in other viral infections. Given these facts and the growing uncertainty about these agents for the treatment of COVID-19, it is clear that at the very least thoughtful planning and data collection from randomized clinical trials are needed to understand what if any role these agents may have in this disease. In this article, we review the datasets that support or detract from the use of these agents for the treatment of COVID-19 and render a data informed opinion that they should only be used with caution and in the context of carefully thought out clinical trials, or on a case-by-case basis after rigorous consideration of the risks and benefits of this therapeutic approach.

Hydroxychloroquine for COVID-19: What is our Current State of Knowledge?

Chloroquine and Hydroxychloroquine are drugs which have been widely used in malaria and rheumatoid arthritis respectively for over 50 years. There was anecdotal evidence of their efficacy in the earlier SARS outbreak in 2003. This prompted physicians from across the world to use them in the present SARS-CoV- 2 pandemic that is currently sweeping the globe, with 5 million people already infected to date. These drugs are already in widespread use for the treatment of COVID-19 in India, mainly because they are cheap and easily available, and because of the absence of any readily available alternative therapy. This timely review discusses the pre-clinical evidence, and data from the eight available clinical trials. We emphasise that careful monitoring for cardiac toxicity is required when these drugs are used. Finally, we conclude that current data does not allow us to recommend for or against the use of these drugs. Results of two large RCTs, one from the NIH and the other from WHO (Solidarity) are eagerly awaited before the role of these drugs in COVID-19 can be definitively established.

No evidence so far on the protective effect of hydroxychloroquine to prevent COVID-19: response to the comment by Joob and Wiwanitkit

Chloroquine and hydroxychloroquine as available weapons to fight COVID-19

No evidence so far on the protective effect of hydroxychloroquine to prevent COVID-19: response to the comment by Joob and Wiwanitkit.

Clinical Implications of Chloroquine and Hydroxychloroquine Ototoxicity for COVID-19 Treatment: A Mini-Review

At this time of the COVID-19 pandemic, potentially effective treatments are currently under urgent investigation. Benefits of chloroquine and hydroxychloroquine for the treatment of COVID-19 infection have been proposed and clinical trials are underway. Chloroquine and hydroxychloroquine, typically used for the treatment of malaria and autoimmune diseases, have been considered for off-label use in several countries. In the literature, there are reports of ototoxic effects of the drugs causing damage to the inner ear structures, which then result in hearing loss, tinnitus, and/or imbalance. This mini-review represents a summary of the findings from a systematic search regarding ototoxicity of chloroquine and hydroxychloroquine in the published literature. The characteristics of sensorineural hearing loss and/or tinnitus after chloroquine or hydroxychloroquine treatment can be temporary but reports of persistent auditory and vestibular dysfunction exist. These are not frequent, but the impact can be substantial. Additionally, abnormal cochleovestibular development in the newborn was also reported after chloroquine treatment in pregnant women. The suggested dose of chloroquine for COVID-19 infection is considerably higher than the usual dosage for malaria treatment; therefore, it is plausible that the ototoxic effects will be greater. There are potential implications from this review for survivors of COVID-19 treated with chloroquine or hydroxychloroquine. Patient reports of hearing loss, tinnitus, or imbalance should be noted. Those with troublesome hearing loss, tinnitus and/or imbalance are encouraged to be referred for hearing evaluation and interventions once they are stable. Clinical trials of chloroquine or hydroxychloroquine should also consider including audiological monitoring in the protocol.

The Food and Drug Administration (FDA) warned against the use of Hydroxychloroquine or chloroquine for Covid-19 outside of a hospital or a clinical trial setting due to the risk of QT interval prolongation, ventricular tachycardia and the increased risk of these complications when combined with some antibiotics such as azithromycin. Several studies have reported no benefit of Hydroxychloroquine or chloroquine, when used alone or with a macrolide in COVID-19 hospitalized patients. Despite these warnings, in several developing countries the official guidelines for treatment of Covid-19 patients at the primary care level recommend Hydroxychloroquine and azithromycin, among other treatments, as the first-choice for mild symptomatic Covid-19 patients, asymptomatic contacts or for prophylaxis. In our opinion there is a primum non nocere dilemma during this Covid-19 pandemic. In order to solve this bioethical problem, we strongly recommend that a randomized controlled trial in a primary care setting be carried out as a matter of urgency in these areas of the world.

An Observational Cohort Study of Hydroxychloroquine and Azithromycin for COVID-19: (Can't Get No) Satisfaction

It can be said that SARS-CoV-2 caught the world by surprise. In large part due to globalization, the virus quickly evolved from a serious regional concern to a worldwide pandemic, the likes of which are unprecedented in the last century. In a matter of weeks, COVID-19 became a leading cause of death, with a potential staggering death toll in 2020. Due to a heavy burden of illness, and in the absence of proven therapies, several experimental treatments have been and continue to be prescribed outside of clinical trial settings. Of the potential therapeutic options that showed early promise, few have generated as much controversy, or been subject to such politicization, as hydroxychloroquine. In this issue of the International Journal of Infectious Diseases, Arshad et. al have added more fuel to the fire.

Rationale of a loading dose initiation for hydroxychloroquine treatment in COVID-19 infection in the DisCoVeRy trial

Around the world, several dose regimens of hydroxychloroquine have been used for COVID-19 infection treatment, with the objective of identifying a short-term course. Hydroxychloroquine was found to decrease the viral replication in a concentration-dependent manner in vitro and to be more active when added prior to the viral challenge. A loading dose is used to rapidly attain a target drug concentration, which is usually considered as approximately the steady-state concentration. With a loading dose, the minimum effective concentration is reached much more rapidly than when using only the maintenance dose from the start. Thus, we propose a hydroxychloroquine sulphate dose regimen of 400 mg twice daily at Day 1 then 400 mg once daily from Day 2 to Day 10. We aim to evaluate this in the C-20-15 DisCoVeRy trial.

Chloroquine and hydroxychloroquine in covid-19

Why Your Patients' Believing Hydroxychloroquine and Chloroquine Are 90% Effective for COVID-19 Is 100% Dangerous

Why your Patients' Believing Hydroxychloroquine and Chloroquine are 90% Effective for COVID-19 is 100% Dangerous

An Observational Cohort Study of Hydroxychloroquine and Azithromycin for COVID-19: (Can’t Get No) Satisfaction

COVID-19 coronavirus research has overall low methodological quality thus far: case in point for chloroquine/hydroxychloroquine

OBJECTIVES/BACKGROUND AND OBJECTIVES: Prior epidemics of high-mortality human coronaviruses, such as the acute respiratory syndrome coronavirus (SARS-CoV or SARS-1) in 2003, have driven the characterization of compounds that could be possibly active against the currently emerging novel coronavirus SARS-CoV-2 (COVID-19). Presently, no approved treatment or prophylaxis is available for COVID-19. We comment on the existing COVID-19 research methodologies in general and the published reporting. Given the media attention and claims of effectiveness, we chose chloroquine and hydroxychloroquine, in combination with azithromycin, as an area of COVID-19 research to examine. METHODS/STUDY DESIGN AND SETTING: MEDLINE and EMBASE electronic databases were searched from 2019 to present (April 3rd, 2020) using a mix of keywords such as COVID-19 and chloroquine and hydroxychloroquine. We also searched the largest clinical medicine preprint repository, medRxiv.org. RESULTS: We found 6 studies, 3 randomized control trials and 3 observational studies, focusing on chloroquine and hydroxychloroquine (with azithromycin). We critically appraised the evidence. CONCLUSION: We found that the COVID-19 research methodology is very poor in the area of chloroquine/hydroxychloroquine research. In screening the literature, we observed the same across COVID-19 research in relation to potential treatments. The reporting is very poor and sparse, and patient-important outcomes needed to discern decision-making priorities are not reported. We do understand the barriers to perform rigorous research in health care settings overwhelmed by a novel deadly disease. However, this emergency pandemic situation does not transform flawed methods and data into credible results. The adequately powered, comparative, and robust clinical research that is needed for optimal evidence-informed decision-making remains absent in COVID-19.

Chloroquine and hydroxychloroquine increase risk of death in COVID-19

QT prolongation, torsades de pointes and sudden death with short courses of chloroquine or hydroxychloroquine as used in COVID-19: a systematic review

Chloroquine and hydroxychloroquine are now being widely used as treatments for COVID-19. Both medications prolong the QT interval and accordingly may put patients at increased risk of torsades de pointes and sudden death. Published guidance documents vary in their recommendations for monitoring and managing these potential adverse effects. Accordingly, we set out to conduct a systematic review of the arrhythmogenic effect of short courses of chloroquine or hydroxychloroquine. We searched in MEDLINE and Embase, as well as grey literature up to April 17, 2020, on the risk of QT prolongation, torsades, ventricular arrhythmia, and sudden death with short-term chloroquine and hydroxychloroquine usage. This resulted in 390 unique records, of which fourteen were ultimately selected for qualitative synthesis and which included data on 1515 COVID-19 patients. Approximately 10% of COVID-19 patients treated with these drugs developed QT prolongation. We found evidence of ventricular arrhythmia in two COVID-19 patients out of a group of 28 treated with high-dose chloroquine. A limitation of these results is unclear follow-up and possible publication/reporting bias, but there is compelling evidence that chloroquine and hydroxychloroquine induce significant QT interval prolongation and potentially increase the risk of arrhythmia. Daily ECG monitoring and other risk mitigation strategies should be considered in order to prevent possible harms from what is currently an unproven therapy.

Chloroquine or hydroxychloroquine for prophylaxis of COVID-19

Hydroxychloroquine/ chloroquine as a treatment choice or prophylaxis for Covid-19 at the primary care level in developing countries: A Primum non Nocere dilemma.

Within a large healthcare system, the incidence of positive COVID-19 results and mortality are lower in patients on chronic hydroxychloroquine therapy

Association Between US Administration Endorsement of Hydroxychloroquine for COVID-19 and Outpatient Prescribing

Hydroxychloroquine and azithromycin as potential treatments for COVID-19; clinical status impacts the outcome

Psychiatric Aspects of Chloroquine and Hydroxychloroquine Treatment in the Wake of COVID-19: Psychopharmacological Interactions and Neuropsychiatric Sequelae

BACKGROUND: Chloroquine and hydroxychloroquine are among several experimental treatments being investigated in the urgent response to the COVID-19. With increased use of these medications, physicians need to become knowledgeable of these drugs’ neuropsychiatric side effects and interactions with psychiatric medications. METHODS: Literature review was performed in PubMed from 1950-2020 regarding psychiatric topics and targeted pharmacological properties of chloroquine and hydroxychloroquine. REVIEW: First, chloroquine and hydroxychloroquine may mildly inhibit CYP2D6 metabolism of psychiatric medications, and psychiatric medications that interfere with CYP2D6 or CYP3A4 activity could alter chloroquine and hydroxychloroquine levels. Second, they may prolong the QT interval, warranting caution with concomitant prescription of other QT prolonging agents. Finally, neuropsychiatric side effects are very uncommon but possible, and include a potentially prolonged phenomenon of “psychosis following chloroquine.” Hydroxychloroquine has less information available about its neuropsychiatric side effects than chloroquine, with psychosis literature limited to several case reports. It is not clear whether patients with psychiatric illness are more vulnerable to neuropsychiatric sequela of these medications, however, overdose on these medications by suicidal patients has high risk of mortality. CONCLUSION: The risk of neuropsychiatric side effects of chloroquine and hydroxychloroquine when used for COVID-19 treatment is not known. Best practice may include suicide risk assessment for patients treated with hydroxychloroquine. However, delirium is expected to be a more likely etiology of neuropsychiatric symptoms in critically ill patients treated for COVID-19, and adjustment disorder is a much more likely etiology of anxiety and depression symptoms than the side effects of chloroquine or hydroxychloroquine.

Emerging Treatment and Prevention Strategies against COVID-19: A Brief Update

Patients with novel coronavirus disease 2019 (COVID-19) are at significantly increased risk for mortality and morbidity. Current management remains supportive care, ranging from symptomatic outpatient management to full–intensive care support, including intravenous fluids, invasive, and non-invasive oxygen supplementation. In patients with septic shock, treatment with antibiotics and vasopressors are recommended to keep mean arterial pressure (MAP) ≥ 65 mm Hg and lactate < 2 mmol/L. Because of the lack of effectiveness and possible adverse effects, routine corticosteroids should be avoided unless they are indicated for another reason (exacerbation of asthma or chronic obstructive pulmonary disease [COPD], and septic shock in whom fluids and vasopressors do not restore hemodynamic stability). There is currently no sufficient evidence of efficacy of hydroxychloroquine/chloroquine, remdesivir, and other antivirals in the treatment or prevention of COVID-19. Limited evidence shows that COVID-19 convalescent plasma can be used as a treatment of COVID-19 without the occurrence of severe adverse events. Drug regulatory agencies granted an emergency-use authorization of chloroquine/hydroxychloroquine and remdesivir to treat patients when a clinical trial is not available or participation is not feasible. Chloroquine and hydroxychloroquine are associated with QT interval prolongation and life-threatening cardiac arrhythmia in patients with pre-existing cardiovascular disease. Guidelines are issued for use of convalescent plasma in patients with serious or immediately life-threatening COVID-19. Data from several ongoing randomized controlled trials will provide further evidence regarding the safety and efficacy of these drugs for the treatment of COVID-19.

QT prolongation, torsades de pointes, and sudden death with short courses of chloroquine or hydroxychloroquine as used in COVID-19: A systematic review

Chloroquine and hydroxychloroquine are now being widely used for treatment of COVID-19. Both medications prolong the QT interval and accordingly may put patients at increased risk for torsades de pointes and sudden death. Published guidance documents vary in their recommendations for monitoring and managing these potential adverse effects. Accordingly, we set out to conduct a systematic review of the arrhythmogenic effect of short courses of chloroquine or hydroxychloroquine. We searched on MEDLINE and Embase, as well as in the gray literature up to April 17, 2020, for the risk of QT prolongation, torsades, ventricular arrhythmia, and sudden death with short-term chloroquine and hydroxychloroquine usage. This search resulted in 390 unique records, of which 41 were ultimately selected for qualitative synthesis and which included data on 1515 COVID-19 patients. Approximately 10% of COVID-19 patients treated with these drugs developed QT prolongation. We found evidence of ventricular arrhythmia in 2 COVID-19 patients from a group of 28 treated with high-dose chloroquine. Limitations of these results are unclear follow-up and possible publication/reporting bias, but there is compelling evidence that chloroquine and hydroxychloroquine induce significant QT-interval prolongation and potentially increase the risk of arrhythmia. Daily electrocardiographic monitoring and other risk mitigation strategies should be considered in order to prevent possible harms from what is currently an unproven therapy.

Hydroxychloroquine for the management of COVID-19: Hope or Hype? A Systematic review of the current evidence

Purpose: The COVID-19 Pandemic has literally left the world breathless in the chase for Pharmacotherapy. With the vaccine approval likely more than a year away and novel drugs in early clinical trials, repurposing of existing drugs takes the center stage. A potential drug discussed both in geopolitical and global scientific community is hydroxychloroquine (HCQ). We intend to systematically weigh and analyze the existing evidence of HCQ in the light of published and pre-print data available so far. Methods: PubMed Ovid MEDLINE, EMBASE, Google scholar databases and official clinical trial Registries of the United States, China, WHO ICTRP were electronically searched for studies for the use of HCQ in patients with COVID-19. Pre-proof article repositories like MedRxiv, BioRxiv, and ChemRxiv were also included in the search. The literature was critically appraised. Results: Total 71 articles were available as of 15 th April of which articles of relevance (three invitro studies, two open label non-randomized trials, two open label randomized control trials, one follow-up study, three reviews, ten short communications) and 88 clinical trials registered in three clinical trial registries were analyzed. HCQ seems to be efficient in inhibiting of SARS CoV-2 in in-vitro cell lines; there is lack of strong evidence from human studies. Conclusions: The in-vitro cell culture based data of viral inhibition does not suffice for the use of hydroxychloroquine in the patients with COVID-19. Currently literature shows inadequate, low level evidence in human studies. Scarcity of safety and efficacy data warrants medical communities, health care agencies and governments across the world against the widespread use of HCQ in COVID-19 prophylaxis and treatment, until robust evidence becomes available. Keywords: Hydroxychloroquine, SARS-CoV-2, COVID-19, Corona virus, nCov2, systematic review

Chloroquine and hydroxychloroquine to treat COVID-19: between hope and caution.

Are hydroxychloroquine and chloroquine effective in the treatment of SARS-COV-2 (COVID-19)?

Data sources The authors of this rapid review did not disclose which electronic databases were included in their literature search. The inclusion and exclusion criteria for the data sources are not reported in the manuscript.Study selection The authors included six studies on the effectiveness of hydroxychloroquine or chloroquine for the prevention and treatment of COVID-19 in humans. Studies comprised of two randomised controlled trials, two non-randomised trials both of which were non-blinded and open-label and one that was uncontrolled, a prospective cohort study and an interim report. The authors did not report details of any studies that were excluded.Data extraction and synthesis The data extraction methodology was not reported and it is unclear if the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines were followed. Treatment regimens and the study outcomes were extracted where available and overall findings were presented in a table. There were no comparable outcome measures; therefore, results were deemed unsuitable to combine and no statistical analyses were carried out. A narrative synthesis of each study is presented.Results The results of the studies in this rapid review are difficult to quantify as each study had different outcome parameters. Due to the heterogeneity of the studies, results were not combined, and no statistical analysis was carried out. Narrative synthesis of each of the included studies identified important and significant limitations, precluding the studies from demonstrating a statistically significant difference in outcomes.Conclusions This review highlights the urgent need for more high quality evidence on the use of hydroxychloroquine and chloroquine in the prevention and treatment of COVID-19. The results of the studies included should be interpreted with caution due to the weak supporting data and numerous methodological limitations. The authors suggested that the studies be viewed as hypothesis-generating and should not be used in decision making around the recommendations and guidelines in the prevention and treatment of COVID-19. There are currently several ongoing randomised controlled trials looking at the effectiveness and efficacy of these drugs on COVID-19. It is hoped the outcome of these studies can help guide future recommendations and national guidelines.

Data sources The authors of this rapid review did not disclose which electronic databases were included in their literature search. The inclusion and exclusion criteria for the data sources are not reported in the manuscript. Study selection The authors included six studies on the effectiveness of hydroxychloroquine or chloroquine for the prevention and treatment of COVID-19 in humans. Studies comprised of two randomised controlled trials, two non-randomised trials both of which were non-blinded and open-label and one that was uncontrolled, a prospective cohort study and an interim report. The authors did not report details of any studies that were excluded. Data extraction and synthesis The data extraction methodology was not reported and it is unclear if the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines were followed. Treatment regimens and the study outcomes were extracted where available and overall findings were presented in a table. There were no comparable outcome measures; therefore, results were deemed unsuitable to combine and no statistical analyses were carried out. A narrative synthesis of each study is presented. Results The results of the studies in this rapid review are difficult to quantify as each study had different outcome parameters. Due to the heterogeneity of the studies, results were not combined, and no statistical analysis was carried out. Narrative synthesis of each of the included studies identified important and significant limitations, precluding the studies from demonstrating a statistically significant difference in outcomes. Conclusions This review highlights the urgent need for more high quality evidence on the use of hydroxychloroquine and chloroquine in the prevention and treatment of COVID-19. The results of the studies included should be interpreted with caution due to the weak supporting data and numerous methodological limitations. The authors suggested that the studies be viewed as hypothesis-generating and should not be used in decision making around the recommendations and guidelines in the prevention and treatment of COVID-19. There are currently several ongoing randomised controlled trials looking at the effectiveness and efficacy of these drugs on COVID-19. It is hoped the outcome of these studies can help guide future recommendations and national guidelines.

[Potential harms associated with 4-aminoquinoline treatment].

Hydroxychloroquine and chloroquine are currently being evaluated as treatment against COVID-19. These drugs are associated with some potential harms, including QTc-interval prolongation, hypoglycaemia, severe skin reactions and psychiatric effects. Use of hydroxychloroquine or chloroquine should be reserved to current indications or clinical trials, as recommended by several governmental medical products agencies.

An independent appraisal and re-analysis of hydroxychloroquine treatment trial for COVID-19

RETRACTED: Hydroxychloroquine or chloroquine with or without a macrolide for treatment of COVID-19: a multinational registry analysis

BACKGROUND: Hydroxychloroquine or chloroquine, often in combination with a second-generation macrolide, are being widely used for treatment of COVID-19, despite no conclusive evidence of their benefit. Although generally safe when used for approved indications such as autoimmune disease or malaria, the safety and benefit of these treatment regimens are poorly evaluated in COVID-19. METHODS: We did a multinational registry analysis of the use of hydroxychloroquine or chloroquine with or without a macrolide for treatment of COVID-19. The registry comprised data from 671 hospitals in six continents. We included patients hospitalised between Dec 20, 2019, and April 14, 2020, with a positive laboratory finding for SARS-CoV-2. Patients who received one of the treatments of interest within 48 h of diagnosis were included in one of four treatment groups (chloroquine alone, chloroquine with a macrolide, hydroxychloroquine alone, or hydroxychloroquine with a macrolide), and patients who received none of these treatments formed the control group. Patients for whom one of the treatments of interest was initiated more than 48 h after diagnosis or while they were on mechanical ventilation, as well as patients who received remdesivir, were excluded. The main outcomes of interest were in-hospital mortality and the occurrence of de-novo ventricular arrhythmias (non-sustained or sustained ventricular tachycardia or ventricular fibrillation). FINDINGS: 96â032 patients (mean age 53·8 years, 46·3% women) with COVID-19 were hospitalised during the study period and met the inclusion criteria. Of these, 14â888 patients were in the treatment groups (1868 received chloroquine, 3783 received chloroquine with a macrolide, 3016 received hydroxychloroquine, and 6221 received hydroxychloroquine with a macrolide) and 81â144 patients were in the control group. 10â698 (11·1%) patients died in hospital. After controlling for multiple confounding factors (age, sex, race or ethnicity, body-mass index, underlying cardiovascular disease and its risk factors, diabetes, underlying lung disease, smoking, immunosuppressed condition, and baseline disease severity), when compared with mortality in the control group (9·3%), hydroxychloroquine (18·0%; hazard ratio 1·335, 95% CI 1·223-1·457), hydroxychloroquine with a macrolide (23·8%; 1·447, 1·368-1·531), chloroquine (16·4%; 1·365, 1·218-1·531), and chloroquine with a macrolide (22·2%; 1·368, 1·273-1·469) were each independently associated with an increased risk of in-hospital mortality. Compared with the control group (0·3%), hydroxychloroquine (6·1%; 2·369, 1·935-2·900), hydroxychloroquine with a macrolide (8·1%; 5·106, 4·106-5·983), chloroquine (4·3%; 3·561, 2·760-4·596), and chloroquine with a macrolide (6·5%; 4·011, 3·344-4·812) were independently associated with an increased risk of de-novo ventricular arrhythmia during hospitalisation. INTERPRETATION: We were unable to confirm a benefit of hydroxychloroquine or chloroquine, when used alone or with a macrolide, on in-hospital outcomes for COVID-19. Each of these drug regimens was associated with decreased in-hospital survival and an increased frequency of ventricular arrhythmias when used for treatment of COVID-19. FUNDING: William Harvey Distinguished Chair in Advanced Cardiovascular Medicine at Brigham and Women's Hospital.

Chloroquine and hydroxychloroquine to treat COVID-19: between hope and caution

Enantiomers of Chloroquine and Hydroxychloroquine Exhibit Different Activities Against SARS-CoV-2 in vitro, Evidencing S-Hydroxychloroquine as a Potentially Superior Drug for COVID-19

In all of the clinical trials for COVID-19 conducted thus far and among those ongoing involving chloroquine or hydroxychloroquine, the drug substance used has invariably been chloroquine (CQ) diphosphate or hydroxychloroquine (HCQ) sulfate, i.e., the phosphoric or sulfuric acid salt of a racemic mixture of R- and S-enantiomer (50/50), respectively. As a result, the clinical outcome from previous CQ or HCQ trials were, in fact, the collective manifestation of both R and S-enantiomers with inherent different pharmacodynamic and pharmacokinetic properties, and toxicity liabilities. Our data for the first time demonstrated the stereoselective difference of CQ and HCQ against live SARS-CoV-2 virus in a Biosafety Level 3 laboratory. S-chloroquine (S-CQ) and S-hydroxychloroquine (S-HCQ) were found to be 27% and 60% more active against SARS-CoV-2, as compared to R-CQ and R-HCQ, respectively. With these data and previous work on stereoselective metabolism of CQ and HCQ, we recommend that future clinical studies should employ S-HCQ as a potentially superior drug substance for the treatment of COVID-19 for improved therapeutic index.

Covid-19: US gives emergency approval to hydroxychloroquine despite lack of evidence.

Chloroquine and Hydroxychloroquine Retinal Toxicity Consideration in the Treatment of COVID-19

The proposed doses of chloroquine (CQ) and hydroxychloroquine (HCQ) for treatment of COVID-19 (1000 mg/day for 10 days, CQ; 800 mg first day then 400 mg/day for 5 days, HCQ) in many guidelines worldwide, are considerably higher than the maximum recommended daily safe doses of both agents (≤2.3 mg/kg/day, CQ; ≤5.0 mg/kg/day, HCQ) for development of retinal toxicity. Irreversible retinal damage can occur if the exposure to the safe doses is >5 years. It is not known whether exposure to high doses over a short period of time can also cause the damage. We recommend that before prescribing CQ or HCQ, history of ocular disease should be obtained to avoid the prescription if appropriate. If either agent is to be used, routine baseline ocular examination is not absolutely necessary. Patients who do not have ocular disease should also be informed about the potential risk of retinal toxicity. Both agents, however, have not yet been proven to be beneficial to COVID-19.

Hydroxychloroquine use in the COVID-19 patient.

Hydroxychloroquine (HCQ) has multiple potential antiviral mechanisms of action that differ according to the pathogen studied (eg, Chikungunya, Dengue virus, human immunodeficiency virus, poliovirus, Zika virus). Data on HCQ for treatment of coronavirus disease 2019 (COVID-19) are rapidly evolving. To date there is no evidence from randomized controlled trials that any single therapy improves outcomes in patients infected with COVID-19. There are also no clinical trial data supporting prophylactic HCQ therapy in COVID-19. Hydroxychloroquine (HCQ) use in patients with COVID-19 is being investigated examining prophylaxis, postexposure prophylaxis, and treatment regimens.

Hydroxychloroquine and chloroquine in COVID-19: should they be used as standard therapy?

The pandemic of the new coronavirus, known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has urged the nations to an unprecedented world-wide reaction, including an accelerated exploration of therapeutic options. In the absence of a vaccine and specifically designed antivirals, the medical community has proposed the use of various previously available medications in order to reduce the number of patients requiring prolonged hospitalizations, oxygen therapy, and mechanical ventilation and to decrease mortality from coronavirus disease 2019 (COVID-19). Hydroxychloroquine and chloroquine are among the proposed drugs and are the most widely used so far, despite the lack of robust evidence on their usefulness. The objective of this article is to review and discuss the possible role of these drugs in the therapy of COVID-19.

Systematic benefit-risk assessment for the use of chloroquine or hydroxychloroquine as a treatment for COVID-19: Establishing a framework for rapid decision-making

Objectives: Given the current pandemic, there is an urgent need to identify effective, safe treatments for COVID-19 (coronavirus disease). A systematic benefit-risk assessment was designed and conducted to strengthen the ongoing monitoring of the benefit-risk balance for chloroquine and hydroxychloroquine in COVID-19 treatment. Methods: The overall benefit-risk of the use of chloroquine or hydroxychloroquine as a treatment for COVID-19 compared to standard of care, placebo or other treatments was assessed using the Benefit-Risk Action Team (BRAT) framework. We searched PubMed and Google Scholar to identify literature reporting clinical outcomes in patients taking chloroquine or hydroxychloroquine for COVID-19. A value tree was constructed and key benefits and risks were ranked by two clinicians in order of considered importance. Results: Several potential key benefits and risks were identified for use of hydroxychloroquine or chloroquine in COVID-19 treatment. For the benefit of virological clearance, three studies were identified. A significant risk difference (RD) between hydroxychloroquine and the comparator group (standard of care) was found for only one study (RD=0.58, 95% CI: 0.17, 0.98). The risk difference was not significant for the other two studies (RD=-0.07, 95% CI:-0.75, 0.61 and RD=0.08, 95% CI:-0.74, 0.91). In addition, no significant risk difference between hydroxychloroquine and the comparator group (standard of care) was identified for the risk of abnormal liver function tests (LFTs) (RD=0.07, 95% CI: -0.28, 0.41). Conclusions: Overall, no conclusion can be made on the benefit-risk profile of hydroxychloroquine or chloroquine in the treatment of COVID-19 compared to standard of care, placebo or other treatments at this time. Whilst the availability of comparative data are limited, the current framework summarises the key anticipated benefits and risks. As further data from clinical trials and real world use on these benefits and risks becomes available, this can be incorporated into the framework for an ongoing benefit-risk assessment.

Safety concerns with higher dosage chloroquine in COVID-19 patients

Caution and clarity required in the use of chloroquine for COVID-19

ChemoPROphyLaxIs with hydroxychloroquine For covId-19 infeCtious disease (PROLIFIC) to prevent covid-19 infection in frontline healthcare workers: A structured summary of a study protocol for a randomised controlled trial

OBJECTIVES: PRIMARY OBJECTIVE: To determine whether chemoprophylaxis with hydroxychloroquine versus placebo increases time to contracting coronavirus disease 2019 (COVID-19) in frontline healthcare workers. SECONDARY OBJECTIVES: 1. To determine whether chemoprophylaxis with daily versus weekly dosing of hydroxychloroquine increases time to contracting COVID-19 disease in frontline healthcare workers. 2. To compare the number of COVID-19 cases between each trial arm on the basis of positive tests (as per current clinical testing methods and/or serology). 3. To compare the percentage of COVID-19 positive individuals with current testing methods versus serologically-proven COVID-19 in each trial arm. 4. To compare COVID-19 disease severity in each trial arm. 5. To compare recovery time from COVID-19 infection in each trial arm. EXPLORATORY OBJECTIVES: 1. To determine compliance (as measured by trough pharmacokinetic hydroxychloroquine levels) on COVID-19 positive tests. 2. To determine if genetic factors determine susceptibility to COVID-19 disease or response to treatment. 3. To determine if blood group determines susceptibility to COVID-19 disease. 4. To compare serum biomarkers of COVID-19 disease in each arm. TRIAL DESIGN: Double-blind, multi-centre, 2-arm (3:3:2 ratio) randomised placebo-controlled trial PARTICIPANTS: National Health Service (NHS) workers who have direct patient contact delivering care to patients with COVID-19. Participants in the trial will be recruited from a number of NHS hospitals directly caring for patients with COVID-19. INCLUSION CRITERIA: 1. Have given written informed consent to participate. 2. Be aged 18 years to 70 years. 3. Not previously have been diagnosed with COVID-19. 4. Work in a high-risk secondary or tertiary healthcare setting (hospitals accepting COVID-19 patients) with direct patient-facing care. EXCLUSION CRITERIA: 1. Known COVID-19 positive test at baseline (if available). 2. Symptomatic for possible COVID-19 at baseline. 3. Known hypersensitivity reaction to hydroxychloroquine, chloroquine or 4-aminoquinolines. 4. Known retinal disease. 5. Known porphyria. 6. Known chronic kidney disease (CKD; eGFR<30ml/min). 7. Known epilepsy. 8. Known heart failure or conduction problems. 9. Known significant liver disease (Gilbert’s syndrome is permitted). 10. Known glucose-6-phosphate dehydrogenase (G6PD) deficiency. 11. Currently taking any of the following contraindicated medications: Digoxin, Chloroquine, Halofantrine, Amiodarone, Moxifloxacin, Cyclosporin, Mefloquine, Praziquantel, Ciprofloxacin, Clarithromycin, Prochlorperazine, Fluconazole. 12. Currently taking hydroxychloroquine or having a clinical indication for taking hydroxychloroquine. 13. Currently breastfeeding. 14. Unable to be followed-up during the trial. 15. Current or future involvement in the active treatment phase of other interventional research studies (excluding observational/non-interventional studies) before study follow-up visit. 16. Not able to use or have access to a modern phone device/web-based technology. 17. Any other clinical reason which may preclude entry in the opinion of the investigator. INTERVENTION AND COMPARATOR: A).. Daily hydroxychloroquine or B).. Weekly hydroxychloroquine or C).. Placebo. The maximum treatment period is approximately 13 weeks per participant. Hydroxychloroquine-identical matched placebo tablets will ensure that all participants are taking the same number and dosing regimen of tablets across the three trial arms. There is no variation in the dose of hydroxychloroquine by weight. The dosing regimen for the three arms of the study (A, B, C) are described in further detail below. Arm A: Active Hydroxychloroquine (– daily dosing and placebo-matched hydroxychloroquine - weekly dosing). Form: Tablets Route: Oral. Dose and Frequency: Active hydroxychloroquine: Days 1-2: Loading phase - 400mg (2 x 200mg tablets) taken twice a day for 2 days. Days 3 onwards: Maintenance Phase - 200mg (1 x 200mg tablet) taken once daily, every day for 90 days (~3 months). Days 3 onwards: Maintenance Phase - 2 tablets taken once a week on the same day each week (every 7(th) day) for 90 days (~3 months). Arm B: Active Hydroxychloroquine (- weekly dosing and placebo matched hydroxychloroquine – daily dosing.) Form: Tablets Route: Oral. Dose and Frequency: Days 1-2: Loading Phase - 400mg (2 x 200mg tablets) taken twice daily for 2 days. Days 3 onwards: Maintenance Phase - 400mg (2 x 200mg tablets) taken once a week on the same day each week (every 7(th) day) for 90 days (~3 months). Days 3 onwards: Maintenance Phase - 1 tablet taken once daily for 90 days (~3 months). Arm C: Matched placebo Hydroxychloroquine (- daily dosing and matched placebo hydroxychloroquine - weekly dosing.) Form: Table. Route: Oral. Frequency: Days 1-2: Loading Phase - 2 tablets taken twice daily for 2 days. Days 3 onwards: Maintenance Phase - 1 tablet taken once daily for 90 days (~3 months). Days 3 onwards: Maintenance Phase - 2 tablets taken once a week on the same day each week (every 7th day) for 90 days (~3 months). A schematic of the dosing schedule can be found in the full study protocol (Additional File 1). MAIN OUTCOMES: Time to diagnosis of positive COVID-19 disease (defined by record of date of symptoms onset and confirmed by laboratory test) RANDOMISATION: Participants will be randomised to either hydroxychloroquine dosed daily with weekly placebo, HCQ dosed weekly with daily placebo, or placebo dosed daily and weekly. Randomisation will be in a 3:3:2 ratio [hydroxychloroquine-(daily), hydroxychloroquine-(weekly), placebo], using stratified block randomisation. Random block sizes will be used, and stratification will be by study site. BLINDING (MASKING): Participants and trial investigators consenting participants, delivering trial assessments and procedures will be blinded to intervention. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): A sufficient number of participants will be enrolled so that approximately 1000 participants in total will have data suitable for the primary statistical analysis. It is anticipated that approximately 1,200 participants will need to be enrolled in total, to allow for a 20% dropout over the period of the trial. This would result in approximately 450:450:300 participants randomised to hydroxychloroquine daily, hydroxychloroquine weekly+daily matched placebo or matched-placebo daily and weekly. TRIAL STATUS: V 1.0, 7(th) April 2020 EU Clinical Trials Register EudraCT Number: 2020-001331-26 Date of registration: 14(th) April 2020 Trial registered before first participant enrolment. Trial site is Cambridge University Hospitals NHS Foundation Trust. Recruitment started on 11(th) May 2020. It is anticipated that the trial will run for 12 months. The recruitment end date cannot yet be accurately predicted. FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest of expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the Standard Protocol Items: Recommendations for Clinical Interventional Trials (SPIRIT) guidelines (Additional file 2).

Reply to Gautret et al: hydroxychloroquine sulfate and azithromycin for COVID-19: what is the evidence and what are the risks?

The severity of COVID-19 has resulted in a global rush to find the right antiviral treatment to conquer the pandemic and to treat patients. This requires reliable studies to support treatment. In a recently published study by Gautret et al. the authors concluded that hydroxychloroquine monotherapy and hydroxychloroquine in combination with azithromycin reduced viral load. However, this trial has several major methodological issues, including the design, outcome measure and the statistical analyses. In this paper we discuss the background, clinical evidence, pharmacology and methodological issues related to this clinical trial. We understand the rush to release results, however in case conclusions are far reaching the evidence needs to be robust.

Hydroxychloroquine use in COVID-19: what is the basis for baseline tests?

The status surrounding chloroquine and other drugs as potential anti-infective agents for COVID-19.

Potential specific therapies in COVID-19

COVID-19 has grown into a global pandemic that has strained healthcare throughout the world. There is a sense of urgency in finding a cure for this deadly virus. In this study, we reviewed the empiric options used in common practice for COVID-19, based on the literature available online, with an emphasis on human experiences with these treatments on severe acute respiratory syndrome-associated coronavirus (SARS-COV-1) and other viruses. Convalescent blood products are the most promising potential treatment for use in COVID-19. The use of chloroquine or hydroxychloroquine (HCQ), remdesivir, and tocilizumab are some of the other promising potential therapies; however, they are yet to be tested in randomized clinical trials (RCTs). The use of lopinavir-ritonavir did not prove beneficial in a large RCT. The use of corticosteroids should be avoided in COVID-19 pneumonia unless used for other indications, based on the suggestion of harm in patients with SARS-COV-1 and Middle Eastern Respiratory Syndrome (MERS) infection. The reviews of this paper are available via the supplemental material section.

Should azithromycin be used to treat COVID-19? A rapid review

BACKGROUND: There are no established effective treatments for COVID-19. While novel drugs are being developed, azithromycin has been identified as a candidate treatment in the interim. AIM: To review the evidence for the effectiveness and safety of azithromycin in treating COVID-19. DESIGN & SETTING: A rapid review of the literature was conducted. METHOD: Electronic searches were conducted on 16 April 2020 of PubMed, TRIP, EPPI COVID Living Map, MedRxiv, GoogleScholar, and Google. In vivo and in vitro studies were included assessing the safety and effectiveness of azithromycin for treatment of COVID-19, and/or the activity of azithromycin against SARS-CoV-2. In vivo studies needed to include a comparator group. RESULTS: Three studies were identified, two in vitro and one in vivo, which were suitable for inclusion. All three were published as pre-prints. The in vitro studies revealed conflicting results, with one finding anti-SARS-CoV-2 activity for azithromycin alone, while the other found activity against SARS-CoV-2 only when azithromycin was combined with hydroxychloroquine. A small trial of 36 patients, with high risk of bias, found superior viral clearance in patients with COVID-19 treated with azithromycin and hydroxychloroquine combined, compared with hydroxychloroquine alone. CONCLUSION: There is no evidence to support the use of azithromycin for the treatment of COVID-19 outside of the context of clinical trials, unless it is used to treat bacterial super-infection. There is extremely limited evidence of a possible synergy between azithromycin and hydroxychloroquine. The adverse events profile of azithromycin in the context of COVID-19 has not yet been established. Well-conducted clinical trials are urgently needed in this area.

Response to: "Risks of hydroxychloroquine use for COVID-19 prophylaxis"

In-silico strategies for probing chloroquine based inhibitors against SARS-CoV-2

The global health emergency of novel COVID-19 is due to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Currently there are no approved drugs for the treatment of coronaviral disease (COVID-19), although some of the drugs have been tried. Chloroquine is being widely used in treatment of SARS-CoV-2 infection. Hydroxychloroquine, the derivative of Chloroquine shows better inhibition than Chloroquine and has in vitro activity against SARS-CoV-2 also used to treat COVID-19. To study the interactions of Chloroquine and derivatives of Chloroquine with SARS-CoV-2, series of computational approaches like pharmacophore model, molecular docking, MM_GBSA study and ADME property analysis are explored. The pharmacophore model and molecular docking study are used to explore the structural properties of the compounds and the ligand-receptor (PDB_ID: 6LU7) interactions respectively. MM_GBSA study gives the binding free energy of the protein-ligand complex and ADME property analysis explains the pharmacological property of the compounds. The resultant best molecule (CQD15) further subjected to molecular dynamics (MD) simulation study which explains the protein stability (RMSD), ligand properties as well as protein-ligand contacts. Outcomes of the present study conclude with the molecule CQD15 which shows better interactions for the inhibition of SARS-CoV-2 in comparison to Chloroquine and Hydroxychloroquine.Communicated by Ramaswamy H. Sarma.

Chloroquine and hydroxychloroquine for COVID-19: A word of caution

Off-label prescribing in the midst of a pandemic: The case of hydroxychloroquine.

There is currently no robust evidence to support prescribing hydroxychloroquine as a treatment or prophylaxis for COVID-19.

No evidence supports the use of ether and chloroform inhalation for treating COVID-19

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

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.

Covid-19: Hydroxychloroquine does not benefit hospitalised patients, UK trial finds

Potential of chloroquine and hydroxychloroquine to treat COVID-19 causes fears of shortages among people with systemic lupus erythematosus

Efficacy and Safety of Hydroxychloroquine and Chloroquine for COVID-19: A systematic review

BACKGROUND: Hydroxychloroquine and chloroquine are widely used to treat hospitalized COVID-19 patients primarily based on antiviral activity in in vitro studies. Our objective was to systematically evaluate their efficacy and safety in hospitalized patients with COVID-19. METHODS: We systematically reviewed PubMed, ClinicalTrials.gov, and Medrxviv for studies of hydroxychloroquine and chloroquine in COVID-19 hospitalized patients on April 26, 2020. We evaluated the quality of trials and observational studies using the Jadad criteria and Newcastle Ottawa Scale, respectively. RESULTS: After a review of 175 citations, we included 5 clinical trials (total of 345 patients), 9 observational studies (n = 2529), and 6 additional studies (n = 775) reporting on the QT interval. Three studies reported treatment benefits including two studies reporting benefit on virologic outcomes, which was statistically significant in one study, and another reported significant improvement on cough symptoms. Three studies reported that treatment was potentially harmful, including an significantly increased risk of mortality in two studies and increased need for respiratory support in another. Eight studies were unable to detect improvements on virologic outcomes (n = 3) or pneumonia or transfer to ICU/death (n = 5). The proportion of participants with critical QTc intervals of [≥] 500 ms or an increase of [≥] 60 ms from baseline ranged from 8.3% to 36% (n = 8). One clinical trial and six observational studies were of good quality. The remaining studies were of poor quality. CONCLUSIONS: Our systematic review of reported clinical studies did not identify substantial evidence to support the efficacy of hydroxychloroquine or chloroquine in hospitalized COVID-19 patients and raises questions about potential harm from QT prolongation and increased mortality.

Model informed dosing of Hydroxycholoroquine in COVID-19 patients: Learnings from the recent experience, remaining uncertainties and Gaps.

AIMS In the absence of a commonly agreed dosing protocol based on pharmacokinetic considerations, the dose and treatment duration for hydroxychloroquine (HCQ) COVID-19 disease currently vary across national guidelines and clinical study protocols. We have used a model-based approach to explore the relative impact of alternative dosing regimens proposed in different dosing protocols for hydroxychloroquine in COVID-19. METHODS We compared different PK exposures using Monte Carlo simulations based on a previously published population pharmacokinetic model in patients with rheumatoid arthritis, externally validated using both independent data in lupus erythematous patients and recent data in French COVID-19 patients. Clinical efficacy and safety information from COVID-19 patients treated with HCQ were used to contextualize and assess the actual clinical value of the model predictions. RESULTS Literature and observed clinical data confirm the variability in clinical responses in COVID-19 when treated with the same fixed doses. Confounding factors were identified that should be taken into account for dose recommendation. For 80% of patients, doses higher than 800mg day on D1 followed by 600mg daily on following days might not be needed for being cured. Limited adverse drug reactions have been reported so far for this dosing regimen, most often confounded by co-medications, comorbidities or underlying COVID-19 disease effects. CONCLUSION Our results were clear indicating the unmet need for characterization of target PK exposures to inform HCQ dosing optimization in COVID-19. Dosing optimization for HCQ in COVID-19 is still an unmet need. Efforts in this sense are a prerequisite for best the benefit/risk balance.

The global health emergency of novel COVID-19 is due to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Currently there are no approved drugs for the treatment of coronaviral disease (COVID-19), although some of the drugs have been tried. Chloroquine is being widely used in treatment of SARS-CoV-2 infection. Hydroxychloroquine, the derivative of Chloroquine shows better inhibition than Chloroquine and has in vitro activity against SARS-CoV-2 also used to treat COVID-19. To study the interactions of Chloroquine and derivatives of Chloroquine with SARS-CoV-2, series of computational approaches like pharmacophore model, molecular docking, MM_GBSA study and ADME property analysis are explored. The pharmacophore model and molecular docking study are used to explore the structural properties of the compounds and the ligand-receptor (PDB_ID: 6LU7) interactions respectively. MM_GBSA study gives the binding free energy of the protein-ligand complex and ADME property analysis explains the pharmacological property of the compounds. The resultant best molecule (CQD15) further subjected to molecular dynamics (MD) simulation study which explains the protein stability (RMSD), ligand properties as well as protein-ligand contacts. Outcomes of the present study conclude with the molecule CQD15 which shows better interactions for the inhibition of SARS-CoV-2 in comparison to Chloroquine and Hydroxychloroquine. Communicated by Ramaswamy H. Sarma

Hydroxychloroquine use in the COVID-19 patient

Hydroxychloroquine (HCQ) has multiple potential antiviral mechanisms of action that differ according to the pathogen studied (eg, Chikungunya, Dengue virus, human immunodeficiency virus, poliovirus, Zika virus). Data on HCQ for treatment of coronavirus disease 2019 (COVID-19) are rapidly evolving. To date, there is no evidence from randomized controlled trials that HCQ, or any single therapy, improves outcomes in patients infected with COVID-19. There are also no clinical trial data supporting prophylactic HCQ therapy in COVID-19. Use of HCQ in patients with COVID-19 is being investigated for prophylaxis, postexposure prophylaxis, and treatment.

Does Hydroxychloroquine Combat COVID-19? A Timeline of Evidence

Does hydroxychloroquine combat COVID-19? A timeline of evidence

Chloroquine, hydroxychloroquine, and COVID-19: systematic review and narrative synthesis of efficacy and safety

Background: The COVID-19 pandemic has required clinicians to urgently identify new treatment options or the repurposing of existing drugs. Several drugs are now being repurposed with the aim of identifying if these drugs provide some level of disease resolution. Of particular interest are chloroquine (CQ) and hydroxychloroquine (HCQ), first developed as an antimalarial therapy. There is increasing concern with regards to the efficacy and safety of these agents. The aims of this review are to systematically identify and collate studies describing the use of CQ and HCQ in human clinical trials and provide a detailed synthesis of evidence of its efficacy and safety. Methods and Findings: Searches for (COVID AND chloroquine [title/abstract] AND outcomes[full text]) and two (COVID AND hydroxychloroquine[title/abstract] AND outcomes[full text]) yielded 272 unique articles. Unique articles were manually checked for inclusion and exclusion criteria and also subjected to a quality appraisal assessment. A total of 19 articles were included in the systematic review. Seventy-five percent of observational studies employing an endpoint specific to efficacy recorded no significant difference in the attainment of outcomes, between COVID-19 patients given a range of CQ and/or HCQ doses, and the control groups. All clinical trials and 82% of observational studies examining an indicator unique to drug safety discovered a higher probability of adverse events in those treated patients suspected of, and diagnosed with, COVID-19. Seventy-five percent of the total papers focusing on cardiac side-effects found a greater incidence among patients administered a wide range of CQ and/or HCQ doses, with QTc prolongation the most common finding, in addition to its consequences of VT and cardiac arrest. Of the total studies using mortality rate as an end-point, 60% reported no significant change in the risk of death, while 30% showed an elevation, and 10% a depression, in treated relative to control patients. Conclusion: The strongest available evidence suggests that, relative to standard in-hospital management of symptoms, the use of CQ and HCQ to treat hospitalised COVID-19 patients has likely been unsafe. At the very least, the poor quality of data failing to find any significant changes in the risk of VT should preclude definitive judgment on drug safety until the completion of high-quality randomised clinical trials.

Covid-19: US gives emergency approval to hydroxychloroquine despite lack of evidence

Quantifying treatment effects of hydroxychloroquine and azithromycin for COVID-19: a secondary analysis of an open label non-randomized clinical trial (Gautret et al, 2020)

Human infections with a novel coronavirus (SARS-CoV-2) were first identified via syndromic surveillance in December of 2019 in Wuhan China. Since identification, infections (coronavirus disease-2019; COVID-19) caused by this novel pathogen have spread globally, with more than 250,000 confirmed cases as of March 21, 2020. An open-label clinical trial has just concluded, suggesting improved resolution of viremia with use of two existing therapies: hydroxychloroquine (HCQ) as monotherapy, and in combination with azithromycin (HCQ-AZ). The results of this important trial have major implications for global policy in the rapid scale-up and response to this pandemic. The authors present results with p-values for differences in proportions between the study arms, but their analysis is not able to provide effect size estimates. To address this gap, more modern analytical methods including survival models, have been applied to these data, and show modest to no impact of HCQ treatment, with more significant effects from the HCQ-AZ combination, potentially suggesting a role for co-infections in COVID-19 pathogenesis. The trial of Gautret and colleagues, with consideration of the effect sizes, and p-values from multiple models, does not provide sufficient evidence to support wide-scale rollout of HCQ monotherapy for the treatment of COVID-19; larger randomized studies should be considered. The trial of Gautret and colleagues, with consideration of the effect sizes, and p-values from multiple models, does not provide sufficient evidence to support wide-scale rollout of HCQ monotherapy for the treatment of COVID-19; larger randomized studies should be considered. These data also suggest further randomized-controlled studies of HCQ-AZ combination therapy should be undertaken.

Efficacy of hydroxychloroquine in patients with COVID-19: results of a randomized clinical trial

Aims: Studies have indicated that chloroquine (CQ) shows antagonism against COVID-19 in vitro. However, evidence regarding its effects in patients is limited. This study aims to evaluate the efficacy of hydroxychloroquine (HCQ) in the treatment of patients with COVID-19. Main methods: From February 4 to February 28, 2020, 62 patients suffering from COVID-19 were diagnosed and admitted to Renmin Hospital of Wuhan University. All participants were randomized in a parallel-group trial, 31 patients were assigned to receive an additional 5-day HCQ (400 mg/d) treatment, Time to clinical recovery (TTCR), clinical characteristics, and radiological results were assessed at baseline and 5 days after treatment to evaluate the effect of HCQ. Key findings: For the 62 COVID-19 patients, 46.8% (29 of 62) were male and 53.2% (33 of 62) were female, the mean age was 44.7 (15.3) years. No difference in the age and sex distribution between the control group and the HCQ group. But for TTCR, the body temperature recovery time and the cough remission time were significantly shortened in the HCQ treatment group. Besides, a larger proportion of patients with improved pneumonia in the HCQ treatment group (80.6%, 25 of 31) compared with the control group (54.8%, 17 of 31). Notably, all 4 patients progressed to severe illness that occurred in the control group. However, there were 2 patients with mild adverse reactions in the HCQ treatment group. Significance: Among patients with COVID-19, the use of HCQ could significantly shorten TTCR and promote the absorption of pneumonia.

Hydroxychloroquine or chloroquine with or without a macrolide for treatment of COVID-19: a multinational registry analysis

BACKGROUND: Hydroxychloroquine or chloroquine, often in combination with a second-generation macrolide, are being widely used for treatment of COVID-19, despite no conclusive evidence of their benefit. Although generally safe when used for approved indications such as autoimmune disease or malaria, the safety and benefit of these treatment regimens are poorly evaluated in COVID-19. METHODS: We did a multinational registry analysis of the use of hydroxychloroquine or chloroquine with or without a macrolide for treatment of COVID-19. The registry comprised data from 671 hospitals in six continents. We included patients hospitalised between Dec 20, 2019, and April 14, 2020, with a positive laboratory finding for SARS-CoV-2. Patients who received one of the treatments of interest within 48 h of diagnosis were included in one of four treatment groups (chloroquine alone, chloroquine with a macrolide, hydroxychloroquine alone, or hydroxychloroquine with a macrolide), and patients who received none of these treatments formed the control group. Patients for whom one of the treatments of interest was initiated more than 48 h after diagnosis or while they were on mechanical ventilation, as well as patients who received remdesivir, were excluded. The main outcomes of interest were in-hospital mortality and the occurrence of de-novo ventricular arrhythmias (non-sustained or sustained ventricular tachycardia or ventricular fibrillation). FINDINGS: 96 032 patients (mean age 53·8 years, 46·3% women) with COVID-19 were hospitalised during the study period and met the inclusion criteria. Of these, 14 888 patients were in the treatment groups (1868 received chloroquine, 3783 received chloroquine with a macrolide, 3016 received hydroxychloroquine, and 6221 received hydroxychloroquine with a macrolide) and 81 144 patients were in the control group. 10 698 (11·1%) patients died in hospital. After controlling for multiple confounding factors (age, sex, race or ethnicity, body-mass index, underlying cardiovascular disease and its risk factors, diabetes, underlying lung disease, smoking, immunosuppressed condition, and baseline disease severity), when compared with mortality in the control group (9·3%), hydroxychloroquine (18·0%; hazard ratio 1·335, 95% CI 1·223–1·457), hydroxychloroquine with a macrolide (23·8%; 1·447, 1·368–1·531), chloroquine (16·4%; 1·365, 1·218–1·531), and chloroquine with a macrolide (22·2%; 1·368, 1·273–1·469) were each independently associated with an increased risk of in-hospital mortality. Compared with the control group (0·3%), hydroxychloroquine (6·1%; 2·369, 1·935–2·900), hydroxychloroquine with a macrolide (8·1%; 5·106, 4·106–5·983), chloroquine (4·3%; 3·561, 2·760–4·596), and chloroquine with a macrolide (6·5%; 4·011, 3·344–4·812) were independently associated with an increased risk of de-novo ventricular arrhythmia during hospitalisation. INTERPRETATION: We were unable to confirm a benefit of hydroxychloroquine or chloroquine, when used alone or with a macrolide, on in-hospital outcomes for COVID-19. Each of these drug regimens was associated with decreased in-hospital survival and an increased frequency of ventricular arrhythmias when used for treatment of COVID-19. FUNDING: William Harvey Distinguished Chair in Advanced Cardiovascular Medicine at Brigham and Women's Hospital.

Chloroquine and hydroxychloroquine effectiveness in human subjects during coronavirus: a systematic review

In a search to find effective treatments for COVID-19, chloroquine and hydroxychloroquine have gained attention. We aim to provide evidence to support clinical decision-making regarding medication for the treatment of COVID-19 by carrying out a systematic review of the literature. The electronic databases MEDLINE, EMBASE, Global Health, and HMIC were searched up to April 2020. Eligible study outcomes included: extubation or patient recovery. Relevant data were extracted and analysed by narrative synthesis. Our results included six studies in the review of which four studies were of good or fair quality. All eligible studies included were for coronavirus involving the use of either chloroquine or hydroxychloroquine to treat common symptoms such as fever, cough, shortness of breath and fatigue. Outcomes most commonly reported were improved lung function, viral clearance, and hospital discharge. Strong evidence to support the use of chloroquine and hydroxychloroquine in the treatment of COVID-19 is lacking. Fast track trials are riddled with bias and may not conform to rigorous guidelines which may lead to inadequate data being reported. The use of these drugs in combination with other medications may be useful but without knowing which groups they are suited for and when they may cause more harm than good.

Pharmacotherapy in COVID-19; A narrative review for emergency providers

INTRODUCTION: The COVID-19 pandemic has been particularly challenging due to a lack of established therapies and treatment guidelines. With the rapid transmission of disease, even the off-label use of available therapies has been impeded by limited availability. Several antivirals, antimalarials, and biologics are being considered for treatment at this time. The purpose of this literature review is to synthesize the available information regarding treatment options for COVID-19 and serve as a resource for health care professionals. OBJECTIVES: This narrative review was conducted to summarize the effectiveness of current therapy options for COVID-19 and address the controversial use of non-steroidal anti-inflammatory drugs (NSAIDs), angiotensin converting enzyme (ACE) inhibitors, and angiotensin receptor blockers (ARBs). PubMed and SCOPUS were queried using a combination of the keywords "COVID 19," "SARS-CoV-2," and "treatment." All types of studies were evaluated including systematic reviews, case-studies, and clinical guidelines. DISCUSSION: There are currently no therapeutic drugs available that are directly active against SARS-CoV-2; however, several antivirals (remdesivir, favipiravir) and antimalarials (chloroquine, hydroxychloroquine) have emerged as potential therapies. Current guidelines recommend combination treatment with hydroxychloroquine/azithromycin or chloroquine, if hydroxychloroquine is unavailable, in patients with moderate disease, although these recommendations are based on limited evidence. Remdesivir and convalescent plasma may be considered in critical patients with respiratory failure; however, access to these therapies may be limited. Interleukin-6 (IL-6) antagonists may be used in patients who develop evidence of cytokine release syndrome (CRS). Corticosteroids should be avoided unless there is evidence of refractory septic shock, acute respiratory distress syndrome (ARDS), or another compelling indication for their use. ACE inhibitors and ARBs should not be discontinued at this time and ibuprofen may be used for fever. CONCLUSION: There are several ongoing clinical trials that are testing the efficacy of single and combination treatments with the drugs mentioned in this review and new agents are under development. Until the results of these trials become available, we must use the best available evidence for the prevention and treatment of COVID-19. Additionally, we can learn from the experiences of healthcare providers around the world to combat this pandemic.

Ethical issues related to the hydroxychloroquine treatment prescription for Covid-19

Abstract The 2019-20 coronavirus pandemic (COVID-19), has led to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To date, no drugs have demonstrated safety and efficacy in randomized controlled trials for patients with COVID-19. Although the association between Hydroxychloroquine and Azithromycin efficacy lack of solid evidence-base, several governments have adopted it for all virology confirmed Covid-19 cases even for those who are asymptomatic. In the following, we aim to discuss some of the ethical issues associated with the use of this treatment association. We mainly tried to discuss the following controversial questions: Is it ethical not to treat a patient while a treatment exists and is used for other indications than Covid-19 for which it’s not proven yet? If yes, is a randomized controlled trial to prove the hydroxychloroquine for the Covid-19 treatment, necessary, in the context of covid-19 pandemic? If No, is it the government’s right to decide the hydroxychloroquine treatment for all covid-19 patients? and what should be the physicians’ attitudes? Finally, what are the government, physicians, and patient’s rights and responsibilities? The paper conclude that, since health authorities in some countries recommended this off-label use treatment, physicians are challenged by the requirement of veracity while providing care to their patients and the implications of such a requirement; they are facing the challenge of balancing this guideline and their own conviction. Furthermore, the fundamental principles of beneficence and non-maleficence, and respect for persons should underlie any reflection process to address this dilemma. In addition, in a pandemic context, the limits between the government’s, practitioner’s and patient’s rights and obligations are not clear which could significantly endanger the universal ethical principles in clinical practice. It could also undermine any attempt to develop serious clinical trials to prove the considered off-label drug.

Treatment Considerations for COVID-19: A Critical Review of the Evidence (or Lack Thereof)

Abstract The novel severe acute respiratory syndrome coronavirus 2 is causing a worldwide pandemic that may lead to a highly morbid and potentially fatal coronavirus disease-19 (COVID-19). There is currently no drug that has been proven as an effective therapy for COVID-19. Several candidate drugs are being considered and evaluated for treatment. This includes clinically-available drugs, such as chloroquine, hydroxychloroquine, and lopinavir/ritonavir, which are being repurposed for the treatment of COVID-19. Novel experimental therapies, such as remdesivir and favipiravir, are also actively being investigated for antiviral efficacy. Clinically-available and investigational immunomodulators, such as the IL-6 inhibitors tocilizumab and sarilumab and the anti-GMCSF lenzilumab, are being tested for their anticipated effect in counteracting the pro-inflammatory cytokine environment that characterizes severe and critical COVID-19. This review article examines the evidence behind the potential use of these leading drug candidates for the treatment of COVID-19. The authors conclude, based on this review, that there is still no high-quality evidence to support any of these proposed drug therapies. The authors, therefore, encourage the enrollment of eligible patients to multiple ongoing clinical trials that assess the efficacy and safety of these candidate therapies. Until the results of controlled trials are available, none of the suggested therapeutics is clinically proven as an effective therapy for COVID-19.

Does Adding of Hydroxychloroquine to the Standard Care Provide any Benefit in Reducing the Mortality among COVID-19 Patients?: a Systematic Review