Role for antimalarials in the management of COVID-19.

PURPOSE OF REVIEW: The current review highlights recent insights into direct antiviral effects by antimalarials against severe acute respiratory syndrome (SARS)-CoV-2 and other viruses and their potential indirect effects on the host by avoiding exaggerated immune responses (reduced cytokine release, Toll-like receptor response, antigen presentation related to lysosomal processing). RECENT FINDINGS: Currently, there is a large debate on the use of antimalarials for prophylaxis and treatment of SARS-CoV-2-induced disease based on preclinical in-vitro data, small case series and extrapolation from earlier studies of their effect on intracellular pathogens, including many viruses. Hydroxychloroquine (HCQ) or chloroquine have not demonstrated robust efficacy in prior randomized controlled studies against several other viruses. In-vitro data indicate a reduced viral replication of SARS-CoV-2. Especially immunomodulatory effects of antimalarials might also contribute to a clinical efficacy. For SARS-CoV-2 various large studies will provide answers as to whether antimalarials have a place in prophylaxis or treatment of the acute virus infection with SARS-CoV-2 but compelling data are missing so far. SUMMARY: In-vitro data provide a theoretical framework for an efficacy of antimalarials in SARS-CoV-2-induced disease but clinical proof is currently missing.

Hydroxychloroquine for Non-Hospitalized COVID-19 Patients: A Systematic Review and Meta-Analysis of Randomized Clinical Trials. / Hidroxicloroquina para Pacientes com COVID-19 não Hospitalizados: Uma Revisão Sistemática e Metanálise de Ensaios Clínicos Randomizados.

BACKGROUND: Previous systematic reviews have identified no benefit of hydroxychloroquine and chloroquine in non-hospitalized COVID-19 patients. After publication of these reviews, the results of COPE, the largest randomized trial conducted to date, became available. OBJECTIVES: To conduct a systematic review and meta-analyses of randomized clinical trials (RCTs) to synthesize the evidence on the efficacy and safety of hydroxychloroquine and chloroquine for non-hospitalized COVID-19 patients compared to placebo or standard of care. METHODS: Searches were conducted in PubMed, Embase, The Cochrane Library, and ClinicalTrials.gov complemented by manual search. Pairwise meta-analyses, risk of bias, and evidence certainty assessments were conducted, including optimal information size analysis (OIS). A level of significance of 0.05 was adopted in the meta-analysis. PROSPERO: CRD42021265427. RESULTS: Eight RCTs with 3,219 participants were included. COVID-19 hospitalization and any adverse events rates were not significantly different between hydroxychloroquine (5.6% and 35.1%) and control (7.4% and 20.4%) (risk ratio, RR, 0.77, 95% confidence interval, CI, 0.57-1.04, I2: 0%; RR 1.78, 95%-CI 0.90; 3.52, I2: 93%, respectively). The OIS (7,880) was not reached for COVID-19 hospitalization, independently of the simulation for anticipated event rate and RR reduction estimate. CONCLUSION: Evidence of very low certainty showed lack of benefit with hydroxychloroquine in preventing COVID-19 hospitalizations. Despite being the systematic review with the largest number of participants included, the OIS, considering pre-vaccination response to infection, has not yet been reached.

FUNDAMENTO: Revisões sistemáticas anteriores não identificaram benefício do uso da hidroxicloroquina ou da cloroquina em pacientes com COVID-19 não hospitalizados. Após a publicação dessas revisões, os resultados do COPE, o maior ensaio clínico randomizado até hoje, tornaram-se disponíveis. OBJETIVOS: Conduzir uma revisão sistemática e metanálise de ensaios clínicos randomizados (ECRs) para sintetizar as evidências sobre a eficácia e a segurança da hidroxicloroquina e da cloroquina em pacientes com COVID-19 não hospitalizados em comparação a controle ou tratamento padrão. MÉTODOS: As buscas foram conduzidas nos bancos de dados PubMed, Embase, The Cochrane Library e ClinicalTrials.gov, e complementadas por busca manual. Foram realizadas metanálises diretas e avaliações de risco de viés e certeza da evidência, incluindo análise do tamanho ótimo da informação (OIS, optimal information size). Um nível de significância de 0,05 foi adotado na metanálise. PROSPERO: CRD42021265427. RESULTADOS: Oito ECRs com 3219 participantes foram incluídos. As taxas de internação por COVID-19 e de eventos adversos não foram significativamente diferentes entre hidroxicloroquina (5,6% e 5,1%) e controle (7,4% e 20,4%) [risco relativo (RR) 0,77, intervalo de confiança 95% (IC95%), 0,57-1,04, I2: 0%; RR 1,78, IC95% 0,90; 3,52, I2: 93%, respectivamente)]. O OIS (7880) não foi alcançado para hospitalização por COVID-19, independentemente da simulação para a taxa de evento e redução do RR estimados. CONCLUSÃO: A evidência de muito baixa qualidade indicou falta de benefício com hidroxicloroquina em prevenir internações por COVID-19. Apesar de ser a revisão sistemática com o maior número de participantes incluídos, o OIS, considerando a resposta à infecção anterior à vacinação, não foi atingido.

Drug repositioning in the COVID-19 pandemic: fundamentals, synthetic routes, and overview of clinical studies.

INTRODUCTION: Drug repositioning is a strategy to identify a new therapeutic indication for molecules that have been approved for other conditions, aiming to speed up the traditional drug development process and reduce its costs. The high prevalence and incidence of coronavirus disease 2019 (COVID-19) underline the importance of searching for a safe and effective treatment for the disease, and drug repositioning is the most rational strategy to achieve this goal in a short period of time. Another advantage of repositioning is the fact that these compounds already have established synthetic routes, which facilitates their production at the industrial level. However, the hope for treatment cannot allow the indiscriminate use of medicines without a scientific basis. RESULTS: The main small molecules in clinical trials being studied to be potentially repositioned to treat COVID-19 are chloroquine, hydroxychloroquine, ivermectin, favipiravir, colchicine, remdesivir, dexamethasone, nitazoxanide, azithromycin, camostat, methylprednisolone, and baricitinib. In the context of clinical tests, in general, they were carried out under the supervision of large consortiums with a methodology based on and recognized in the scientific community, factors that ensure the reliability of the data collected. From the synthetic perspective, compounds with less structural complexity have more simplified synthetic routes. Stereochemical complexity still represents the major challenge in the preparation of dexamethasone, ivermectin, and azithromycin, for instance. CONCLUSION: Remdesivir and baricitinib were approved for the treatment of hospitalized patients with severe COVID-19. Dexamethasone and methylprednisolone should be used with caution. Hydroxychloroquine, chloroquine, ivermectin, and azithromycin are ineffective for the treatment of the disease, and the other compounds presented uncertain results. Preclinical and clinical studies should not be analyzed alone, and their methodology's accuracy should also be considered. Regulatory agencies are responsible for analyzing the efficacy and safety of a treatment and must be respected as the competent authorities for this decision, avoiding the indiscriminate use of medicines.

Benign COVID-19 in an immunocompromised cancer patient - the case of a married couple.

Respiratory failure in COVID-19 is a common feature in fatal cases and has been considered as a failure of the immune system to control the virus. Here we report the case of COVID-19 affecting an immunocompromised women and her presumably immunocompetent spouse. A married couple (age 60 years) was simultaneously admitted to the emergency department on 10 March 2020 because of dyspnoea and fever, consistent with COVID-19. The wife (patient 1) was partially immunocompromised as a consequence of a recently started chemotherapy with fulvestrant and abemaciclid for recurring breast cancer, her husband (patient 2) had been healthy except for a history of controlled arterial hypertension. Both patients were treated with darunavir/cobicistat and hydroxychloroquine. The clinical course of the immunocompromised partner was benign, without need of intensive care. She was able to leave the hospital on day 6 after admission. In contrast, her husband needed intensive care and his recovery was slow, although eventually successful too. These findings suggest that the course of COVID-19 is not necessarily ominous in the presence of a compromised immune response and tend to reinforce the emerging therapeutic concepts of a controlled mitigation of the immune cascade following SARS CoV-2 infection.

Early experimental COVID-19 therapies: associations with length of hospital stay, mortality and related costs.

AIMS OF THE STUDY: Hydroxychloroquine and lopinavir/ritonavir have been used as experimental therapies to treat COVID-19 during the first wave of the pandemic. Randomised controlled trials have recently shown that there are no meaningful benefits of these two therapies in hospitalised patients. Uncertainty remains regarding the potential harmful impact of these therapies as very early treatments and their burden to the health care system. The present study investigated the length of hospital stay (LOS), mortality, and costs of hydroxychloroquine, lopinavir/ritonavir or their combination in comparison with standard of care among patients hospitalised for coronavirus disease 2019 (COVID-19). METHODS: This retrospective observational cohort study took place in the Geneva University Hospitals, Geneva, Switzerland (n = 840) between 26 February and 31 May 2020. Demographics, treatment regimens, comorbidities, the modified National Early Warning Score (mNEWS) on admission, and contraindications to COVID-19 treatment options were assessed. Outcomes included LOS, in-hospital mortality, and drug and LOS costs. RESULTS: After successful propensity score matching, patients treated with (1) hydroxychloroquine, (2) lopinavir/ritonavir or (3) their combination had on average 3.75 additional hospitalisation days (95% confidence interval [CI] 1.37–6.12, p = 0.002), 1.23 additional hospitalisation days (95% CI −1.24 – 3.51, p = 0.319), and 4.19 additional hospitalisation days (95% CI 1.52–5.31, p <0.001), respectively, compared with patients treated with the standard of care. Neither experimental therapy was significantly associated with mortality. These additional hospital days amounted to 1010.77 additional days for hydroxychloroquine and hydroxychloroquine combined with lopinavir/ritonavir, resulting in an additional cost of US$ 2,492,214 (95%CI US$ 916,839–3,450,619). CONCLUSIONS: Prescribing experimental therapies for COVID-19 was not associated with a reduced LOS and might have increased the pressure put on healthcare systems.

Hydroxychloroquine and COVID-19 - A narrative review.

COVID 19 infection is unarguably the worst pandemic of this century. Till date there is no promising drug and vaccine available to treat this deadly viral infection. In the early phase chloroquine phosphate and hydroxychloroquine sulphate have been used to fight this illness on the basis of handful observational and small randomized and small-randomized studies. The paucity of clinical evidences of an unequivocal beneficial effect of chloroquine and hydroxychloroquine on COVID-19 has resulted in the passionate use of the drug for moderate to severe cases only and stimulated the need for large clinical trials for this and other molecules. In this review, we describe in brief the mechanism of action, the clinical studies, factors for cardiac toxicity, guidelines and future directions for hydroxychloroquine use in management of COVID-19 infection.

Long-term (180-Day) Outcomes in Critically Ill Patients With COVID-19 in the REMAP-CAP Randomized Clinical Trial.

Importance: The longer-term effects of therapies for the treatment of critically ill patients with COVID-19 are unknown. Objective: To determine the effect of multiple interventions for critically ill adults with COVID-19 on longer-term outcomes. Design, Setting, and Participants: Prespecified secondary analysis of an ongoing adaptive platform trial (REMAP-CAP) testing interventions within multiple therapeutic domains in which 4869 critically ill adult patients with COVID-19 were enrolled between March 9, 2020, and June 22, 2021, from 197 sites in 14 countries. The final 180-day follow-up was completed on March 2, 2022. Interventions: Patients were randomized to receive 1 or more interventions within 6 treatment domains: immune modulators (n = 2274), convalescent plasma (n = 2011), antiplatelet therapy (n = 1557), anticoagulation (n = 1033), antivirals (n = 726), and corticosteroids (n = 401). Main Outcomes and Measures: The main outcome was survival through day 180, analyzed using a bayesian piecewise exponential model. A hazard ratio (HR) less than 1 represented improved survival (superiority), while an HR greater than 1 represented worsened survival (harm); futility was represented by a relative improvement less than 20% in outcome, shown by an HR greater than 0.83. Results: Among 4869 randomized patients (mean age, 59.3 years; 1537 [32.1%] women), 4107 (84.3%) had known vital status and 2590 (63.1%) were alive at day 180. IL-6 receptor antagonists had a greater than 99.9% probability of improving 6-month survival (adjusted HR, 0.74 [95% credible interval {CrI}, 0.61-0.90]) and antiplatelet agents had a 95% probability of improving 6-month survival (adjusted HR, 0.85 [95% CrI, 0.71-1.03]) compared with the control, while the probability of trial-defined statistical futility (HR >0.83) was high for therapeutic anticoagulation (99.9%; HR, 1.13 [95% CrI, 0.93-1.42]), convalescent plasma (99.2%; HR, 0.99 [95% CrI, 0.86-1.14]), and lopinavir-ritonavir (96.6%; HR, 1.06 [95% CrI, 0.82-1.38]) and the probabilities of harm from hydroxychloroquine (96.9%; HR, 1.51 [95% CrI, 0.98-2.29]) and the combination of lopinavir-ritonavir and hydroxychloroquine (96.8%; HR, 1.61 [95% CrI, 0.97-2.67]) were high. The corticosteroid domain was stopped early prior to reaching a predefined statistical trigger; there was a 57.1% to 61.6% probability of improving 6-month survival across varying hydrocortisone dosing strategies. Conclusions and Relevance: Among critically ill patients with COVID-19 randomized to receive 1 or more therapeutic interventions, treatment with an IL-6 receptor antagonist had a greater than 99.9% probability of improved 180-day mortality compared with patients randomized to the control, and treatment with an antiplatelet had a 95.0% probability of improved 180-day mortality compared with patients randomized to the control. Overall, when considered with previously reported short-term results, the findings indicate that initial in-hospital treatment effects were consistent for most therapies through 6 months.

Concerted and multidisciplinary management of COVID-19 drug therapies during the first two epidemic waves in a tertiary hospital in Marseille, France: Results of the PHARMA-COVID study.

OBJECTIVES: To evaluate the impact of local therapeutic recommendation updates made by the COVID multidisciplinary consultation meeting (RCP) at the Hôpital Européen Marseille (HEM) through the description of the drug prescriptions for COVID-19 during the first two waves of the epidemic. METHODS: This retrospective observational study analysed data from the hospital's pharmaceutical file. We included all patients hospitalized for COVID-19 between February 1, 2020 and January 21, 2021 and extracted specific anti-COVID-19 therapies (ST) from computerized patient record, as well as patients' demographic characteristics, comorbidities and outcome. The evolution of ST prescriptions during the study period was described and put into perspective with the updates of local recommendations made during the first (V1, from 2/24/2020 to 7/27/2020), and second (V2, from 7/28/2020 to 1/21/2021) epidemic waves. RESULTS: A total of 607 COVID-19 hospitalized patients, 197 during V1 and 410 during V2. Their mean age was 65 years-old, and they presented frequent comorbidities. In total, 93% of hospitalized patients received ST: anticoagulants (90%), glucocorticoids (39%) mainly during V2 (49% vs 17%, P<0.001), and azithromycin (30%) mainly during V1 (71% vs 10%, P<0.001). Lopinavir/ritonavir and hydroxychloroquine were prescribed to 17 and 7 inpatients, respectively, and only during V1. Remdesivir was never administered. A total of 22 inpatients were enrolled into clinical trials. CONCLUSIONS: The effective dissemination of evidence-based and concerted recommendations seems to have allowed an optimized management of COVID-19 drug therapies in the context of this emerging infection with rapidly evolving therapeutic questions.

An electrophysiological substrate of COVID-19.

SARS-CoV-2 infection is associated with an increased risk of late cardiovascular (CV) outcomes. However, more data is needed to describe the electrophysiologic (EP) manifestation of post-acute CV sequelae of COVID-19. We compared two cohorts of adult patients with SARS-CoV-2 polymerase chain reaction (PCR) test and an electrocardiogram (ECG) performed between March 1, 2020, and September 13, 2020, in a retrospective double-cohort study, "Cardiovascular Risk Stratification in Covid-19" (CaVaR-Co19; NCT04555187). Patients with positive PCR comprised a COVID-19(+) cohort (n = 41; 61% women; 80% symptomatic), whereas patients with negative tests formed the COVID-19(-) cohort (n = 155; 56% women). In longitudinal analysis, comparing 3 ECGs recorded before, during, and on average 40 days after index COVID-19 episode, after adjustment for demographic and socioeconomic characteristics, baseline CV risk factors and comorbidities, use of prescription medications (including QT-prolonging drugs) before and during index COVID-19 episode, and the longitudinal changes in RR' intervals, heart rhythm, and ventricular conduction type, only in the COVID-19(+) cohort QTc increased by +30.2(95% confidence interval [CI] 0.1-60.3) ms and the spatial ventricular gradient (SVG) elevation increased by +13.5(95%CI 1.2-25.9)°. In contrast, much smaller, statistically nonsignificant changes were observed in the COVID-19(-) cohort. In conclusion, post-acute CV sequelae of SARS-CoV-2 infection manifested on ECG by QTc prolongation and rotation of the SVG vector upward.

COVID-19: Understanding the impact of anti-hypertensive drugs and hydroxychloroquine on the ACE1 and ACE2 in lung and adipose tissue in SHR and WKY rats.

Hypertensive individuals taking anti-hypertensive drugs from renin-angiotensin system inhibitors may exhibit a more severe evolution of the disease when contracting the SARS-CoV-2 virus (COVID-19 disease) due to potential increases in ACE2 expression. The study investigated ACE1 and ACE2 axes and hydroxychloroquine in the lungs and adipose tissue of male and female normotensive Wistar Kyoto (WKY) and spontaneously hypertensive rats (SHRs). SHRs were treated with losartan (10 mg/kg/day) or captopril (10 mg/kg/day) for 14 days or 7 days with hydroxychloroquine (200 mg/kg/day) in drinking water. WKY rats were also treated for 7 days with hydroxychloroquine. Blood pressure (BP), protein, and mRNA expression of ACE1 and ACE2 were analyzed in serum, adipose, and lung tissues. Losartan and captopril reduced BP in both sexes in SHR, whereas hydroxychloroquine increased BP in WKY rats. Losartan reduced ACE2 in serum and lungs in both sexes and in adipose tissue of male SHRs. Captopril decreased ACE2 protein in the lung of females and in adipose tissue in both sexes of SHRs. Hydroxychloroquine decreased ACE1 and ACE2 proteins in the lungs in both sexes and adipose tissue in male SHRs. In female WKY rats, ACE2 protein was lower only in the lungs and adipose tissue. Losartan effectively inhibited ACE2 in male and captopril in female SHRs. Hydroxychloroquine inhibited ACE2 in male SHRs and female WKY rats. These results further our understanding of the ACE2 mechanism in patients under renin-angiotensin anti-hypertensive therapy and in many trials using hydroxychloroquine for COVID-19 treatment and potential sex differences in response to drug treatment.

Remember, do no harm?

When the advocacy group America's Frontline Doctors appeared on the steps of the United States Supreme Court in 2020, falsely stating that hydroxychloroquine was a cure for COVID-19, their pronouncement was virally shared by right-wing media and soundly debunked by medical academicians. A year later, one of these frontliners, Joseph Ladapo, became the surgeon general of Florida and a faculty member at the University of Florida College of Medicine. He has continued to spread dangerous misinformation about COVID-19 while his academic colleagues are shamefully silent.

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.

Association of Treatment With Hydroxychloroquine or Azithromycin With In-Hospital Mortality in Patients With COVID-19 in New York State.

Importance: Hydroxychloroquine, with or without azithromycin, has been considered as a possible therapeutic agent for patients with coronavirus disease 2019 (COVID-19). However, there are limited data on efficacy and associated adverse events. Objective: To describe the association between use of hydroxychloroquine, with or without azithromycin, and clinical outcomes among hospital inpatients diagnosed with COVID-19. Design, Setting, and Participants: Retrospective multicenter cohort study of patients from a random sample of all admitted patients with laboratory-confirmed COVID-19 in 25 hospitals, representing 88.2% of patients with COVID-19 in the New York metropolitan region. Eligible patients were admitted for at least 24 hours between March 15 and 28, 2020. Medications, preexisting conditions, clinical measures on admission, outcomes, and adverse events were abstracted from medical records. The date of final follow-up was April 24, 2020. Exposures: Receipt of both hydroxychloroquine and azithromycin, hydroxychloroquine alone, azithromycin alone, or neither. Main Outcomes and Measures: Primary outcome was in-hospital mortality. Secondary outcomes were cardiac arrest and abnormal electrocardiogram findings (arrhythmia or QT prolongation). Results: Among 1438 hospitalized patients with a diagnosis of COVID-19 (858 [59.7%] male, median age, 63 years), those receiving hydroxychloroquine, azithromycin, or both were more likely than those not receiving either drug to have diabetes, respiratory rate >22/min, abnormal chest imaging findings, O2 saturation lower than 90%, and aspartate aminotransferase greater than 40 U/L. Overall in-hospital mortality was 20.3% (95% CI, 18.2%-22.4%). The probability of death for patients receiving hydroxychloroquine + azithromycin was 189/735 (25.7% [95% CI, 22.3%-28.9%]), hydroxychloroquine alone, 54/271 (19.9% [95% CI, 15.2%-24.7%]), azithromycin alone, 21/211 (10.0% [95% CI, 5.9%-14.0%]), and neither drug, 28/221 (12.7% [95% CI, 8.3%-17.1%]). In adjusted Cox proportional hazards models, compared with patients receiving neither drug, there were no significant differences in mortality for patients receiving hydroxychloroquine + azithromycin (HR, 1.35 [95% CI, 0.76-2.40]), hydroxychloroquine alone (HR, 1.08 [95% CI, 0.63-1.85]), or azithromycin alone (HR, 0.56 [95% CI, 0.26-1.21]). In logistic models, compared with patients receiving neither drug cardiac arrest was significantly more likely in patients receiving hydroxychloroquine + azithromycin (adjusted OR, 2.13 [95% CI, 1.12-4.05]), but not hydroxychloroquine alone (adjusted OR, 1.91 [95% CI, 0.96-3.81]) or azithromycin alone (adjusted OR, 0.64 [95% CI, 0.27-1.56]), . In adjusted logistic regression models, there were no significant differences in the relative likelihood of abnormal electrocardiogram findings. Conclusions and Relevance: Among patients hospitalized in metropolitan New York with COVID-19, treatment with hydroxychloroquine, azithromycin, or both, compared with neither treatment, was not significantly associated with differences in in-hospital mortality. However, the interpretation of these findings may be limited by the observational design.

National early warning score on admission as risk factor for invasive mechanical ventilation in COVID-19 patients: A STROBE-compliant study.

ABSTRACT: The coronavirus disease (COVID-19) has become a global pandemic. Invasive mechanical ventilation is recommended for the management of patients with COVID-19 who have severe respiratory symptoms. However, various complications can develop after its use. The efficient and appropriate management of patients requires the identification of factors associated with an aggravation of COVID-19 respiratory symptoms to a degree where invasive mechanical ventilation becomes necessary, thereby enabling clinicians to prevent such ventilation. This retrospective study included 138 inpatients with COVID-19 at a tertiary hospital. We evaluated the differences in the demographic and clinical data between 27 patients who required invasive mechanical ventilation and 111 patients who did not. Multivariate logistic regression analysis indicated that the duration of fever, national early warning score (NEWS), and lactate dehydrogenase (LDH) levels on admission were significantly associated with invasive mechanical ventilation in this cohort. The optimal cut-off values were: fever duration ≥1 day (sensitivity 100.0%, specificity 54.95%), NEWS ≥7 (sensitivity 72.73%, specificity 92.52%), and LDH >810 mg/dL (sensitivity 56.0%, specificity 90.29%). These findings can assist in the early identification of patients who will require invasive mechanical ventilation. Further studies in larger patient populations are recommended to validate our findings.

The 'myth of Hydroxychloroquine (HCQ) as post-exposure prophylaxis (PEP) for the prevention of COVID-19' is far from reality.

The efficacy of Hydroxychloroquine (HCQ) as post-exposure prophylaxis (PEP) for the prevention of COVID-19 was contentious. In this randomized control double-blind clinical trial, asymptomatic individuals with direct contact with laboratory-confirmed COVID-19 cases were randomized into PEP/HCQ (N = 574) and control/placebo (N = 594) group. The PEP/HCQ group received tablet HCQ 400 mg q 12 hourly on day one followed by 400 mg once weekly for 3 weeks, and the control/Placebo group received matching Placebo. The incidence of COVID-19 was similar (p = 0.761) in PEP [N = 24 out of 574, (4.2%)] and control [N = 27 out of 594, (4.5%)] groups. Total absolute risk reduction for the incidence of new-onset COVID-19 was -0.3% points with an overall relative risk of 0.91 (95% confidence interval, 0.52 to 1.60) and the number needed to treat (NNT) was 333 to prevent the incident of one case of COVID-19. The study found that, PEP with HCQ was not advantageous for the prevention of COVID-19 in asymptomatic individuals with high risk for SARS-CoV-2 infection. Though HCQ is a safer drug, the practice of irrational and indiscriminate use of HCQ for COVID-19 should be restrained with better pharmacovigilance.