Low dose of hydroxychloroquine reduces fatality of critically ill patients with COVID-19

Infectious Diseases Society of America Guidelines on the Treatment and Management of Patients With COVID-19 (September 2022)

There are many pharmacologic therapies that are being used or considered for treatment of coronavirus disease 2019 (COVID-19), with rapidly changing efficacy and safety evidence from trials. The objective was to develop evidence-based, rapid, living guidelines intended to support patients, clinicians, and other healthcare professionals in their decisions about treatment and management of patients with COVID-19. In March 2020, the Infectious Diseases Society of America (IDSA) formed a multidisciplinary guideline panel of infectious disease clinicians, pharmacists, and methodologists with varied areas of expertise to regularly review the evidence and make recommendations about the treatment and management of persons with COVID-19. The process used a living guideline approach and followed a rapid recommendation development checklist. The panel prioritized questions and outcomes. A systematic review of the peer-reviewed and grey literature was conducted at regular intervals. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to assess the certainty of evidence and make recommendations. Based on the most recent search conducted on 31 May 2022, the IDSA guideline panel has made 32 recommendations for the treatment and management of the following groups/populations: pre- and postexposure prophylaxis, ambulatory with mild-to-moderate disease, and hospitalized with mild-to-moderate, severe but not critical, and critical disease. As these are living guidelines, the most recent recommendations can be found online at: https://idsociety.org/COVID19guidelines. At the inception of its work, the panel has expressed the overarching goal that patients be recruited into ongoing trials. Since then, many trials were conducted that provided much-needed evidence for COVID-19 therapies. There still remain many unanswered questions as the pandemic evolved, which we hope future trials can answer.

COVID-19 and cardiovascular complications: updates of emergency medicine

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and SARS-CoV-2 variants, has become a global pandemic resulting in significant morbidity and mortality. Severe cases of COVID-19 are characterized by hypoxemia, hyper-inflammation, cytokine storm in lung. Clinical studies have reported an association between COVID-19 and cardiovascular disease (CVD). Patients with CVD tend to develop severe symptoms and mortality if contracted COVID-19 with further elevations of cardiac injury biomarkers. Furthermore, COVID-19 itself can induce and promoted CVD development, including myocarditis, arrhythmia, acute coronary syndrome, cardiogenic shock, and venous thromboembolism. Although the direct etiology of SARS-CoV-2 induced cardiac injury remains unknown and under-investigated, it is suspected that it is related to myocarditis, cytokine-mediated injury, microvascular injury, and stress-related cardiomyopathy. Despite vaccinations having provided the most effective approach to reducing mortality overall, an adapted treatment paradigm and regular monitoring of cardiac injury biomarkers is critical for improving outcomes in vulnerable populations at risk for severe COVID-19. In this review, we focus on the latest progress in clinic and research on the cardiovascular complications of COVID-19 and provide a perspective of treating cardiac complications deriving from COVID-19 in Emergency Medicine.

Role and clinical implication of autophagy in COVID-19

The ongoing coronavirus disease 2019 (COVID-19) pandemic constitutes a serious public health concern worldwide. Currently, more than 6 million deaths have occurred despite drastic containment measures, and this number is still increasing. Currently, no standard therapies for COVID-19 are available, which necessitates identifying effective preventive and therapeutic agents against COVID-19. However, developing new drugs and vaccines is a time-consuming process, and therefore, repurposing the existing drugs or redeveloping related targets seems to be the best strategy to develop effective therapeutics against COVID-19. Autophagy, a multistep lysosomal degradation pathway contributing to nutrient recycling and metabolic adaptation, is involved in the initiation and progression of numerous diseases as a part of an immune response. The key role of autophagy in antiviral immunity has been extensively studied. Moreover, autophagy can directly eliminate intracellular microorganisms by selective autophagy, that is, "xenophagy." However, viruses have acquired diverse strategies to exploit autophagy for their infection and replication. This review aims to trigger the interest in the field of autophagy as an antiviral target for viral pathogens (with an emphasis on COVID-19). We base this hypothesis on summarizing the classification and structure of coronaviruses as well as the process of SARS-CoV-2 infection and replication; providing the common understanding of autophagy; reviewing interactions between the mechanisms of viral entry/replication and the autophagy pathways; and discussing the current state of clinical trials of autophagy-modifying drugs in the treatment of SARS-CoV-2 infection. We anticipate that this review will contribute to the rapid development of therapeutics and vaccines against COVID-19.

Treating diabetes with combination of phosphodiesterase 5 inhibitors and hydroxychloroquine-a possible prevention strategy for COVID-19?

Type 2 diabetes (T2D) is one of the major risk factors for developing cardiovascular disease and the resultant devastating morbidity and mortality. The key features of T2D are hyperglycemia, hyperlipidemia, insulin resistance, and impaired insulin secretion. Patients with diabetes and myocardial infarction have worse prognosis than those without T2D. Moreover, obesity and T2D are recognized risk factors in developing severe form of COVID-19 with higher mortality rate. The current lines of drug therapy are insufficient to control T2D and its serious cardiovascular complications. Phosphodiesterase 5 (PDE5) is a cGMP specific enzyme, which is the target of erectile dysfunction drugs including sildenafil, vardenafil, and tadalafil. Cardioprotective effects of PDE5 inhibitors against ischemia/reperfusion (I/R) injury were reported in normal and diabetic animals. Hydroxychloroquine (HCQ) is a widely used antimalarial and anti-inflammatory drug and its hyperglycemia-controlling effect in diabetic patients is also under investigation. This review provides our perspective of a potential use of combination therapy of PDE5 inhibitor with HCQ to reduce cardiovascular risk factors and myocardial I/R injury in T2D. We previously observed that diabetic mice treated with tadalafil and HCQ had significantly reduced fasting blood glucose and lipid levels, increased plasma insulin and insulin-like growth factor-1 levels, and improved insulin sensitivity, along with smaller myocardial infarct size following I/R. The combination treatment activated Akt/mTOR cellular survival pathway, which was likely responsible for the salutary effects. Therefore, pretreatment with PDE5 inhibitor and HCQ may be a potentially useful therapy not only for controlling T2D but also reducing the rate and severity of COVID-19 infection in the vulnerable population of diabetics.

Effect of hydroxychloroquine on beta cell function, insulin resistance, and inflammatory markers in type 2 diabetes patients uncontrolled on glimepiride and metformin therapy

Background

Very few studies have assessed the impact of hydroxychloroquine (HCQ) on insulin resistance, beta cell function, and inflammatory markers in diabetics which takes paramount importance in understanding the mechanism of its anti-diabetic effect.

Objective

To assess the effect of hydroxychloroquine on beta cell function and insulin resistance and inflammatory markers in type 2 diabetes patients uncontrolled on glimepiride and metformin combination.

Study design and method

30 T2DM patients were inadequately controlled on glimepiride and metformin combination with an HbA1c between 7.5 and 10% (both inclusive) and were given hydroxychloroquine 400 mg in addition to glimepiride and metformin during the 12-week study period. Beta cell function, insulin resistance, high-sensitivity C-reactive protein (hsCRP), adiponectin, interleukin-6 (IL6), fasting plasma glucose (FPG), postprandial plasma glucose (PPG), and glycated hemoglobin (HbA1c) were assessed at baseline and at 12 weeks after addition of 400 mg hydroxychloroquine.

Results

With addition of HCQ, there was a significant improvement in both beta cell function and insulin resistance (p < 0.001). There was also significant improvement in FPG, PPG, and HbA1c along with significant improvement in IL6, hsCRP, and adiponectin levels post 12 weeks of adjunctive treatment with hydroxychloroquine. The changes in beta cell function and insulin resistance correlated significantly with the changes in IL6, hsCRP, and adiponectin levels.

Conclusion

Addition of hydroxychloroquine as an add-on drug in uncontrolled diabetes significantly improves the beta cell function and the insulin resistance, along with significant improvement in adiponectin, hsCRP levels, and IL6 levels.

Pharmacological therapies and drug development targeting SARS-CoV-2 infection

The development of therapies for SARS-CoV-2 infection, based on virus biology and pathology, and of large- and small-scale randomized controlled trials, have brought forward several antiviral and immunomodulatory drugs targeting the disease severity. Casirivimab/Imdevimab monoclonal antibodies and convalescent plasma to prevent virus entry, Remdesivir, Molnupiravir, and Paxlovid nucleotide analogs to prevent viral replication, a variety of repurposed JAK-STAT signaling pathway inhibitors, corticosteroids, and recombinant agonists/antagonists of cytokine and interferons have been found to provide clinical benefits in terms of mortality and hospitalization. However, current treatment options face multiple clinical needs, and therefore, in this review, we provide an update on the challenges of the existing therapeutics and highlight drug development strategies for COVID-19 therapy, based on ongoing clinical trials, meta-analyses, and clinical case reports.

Hydroxychloroquine/chloroquine for the treatment of hospitalized patients with COVID-19: An individual participant data meta-analysis

BACKGROUND

Results from observational studies and randomized clinical trials (RCTs) have led to the consensus that hydroxychloroquine (HCQ) and chloroquine (CQ) are not effective for COVID-19 prevention or treatment. Pooling individual participant data, including unanalyzed data from trials terminated early, enables more detailed investigation of the efficacy and safety of HCQ/CQ among subgroups of hospitalized patients.

METHODS

We searched ClinicalTrials.gov in May and June 2020 for US-based RCTs evaluating HCQ/CQ in hospitalized COVID-19 patients in which the outcomes defined in this study were recorded or could be extrapolated. The primary outcome was a 7-point ordinal scale measured between day 28 and 35 post enrollment; comparisons used proportional odds ratios. Harmonized de-identified data were collected via a common template spreadsheet sent to each principal investigator. The data were analyzed by fitting a prespecified Bayesian ordinal regression model and standardizing the resulting predictions.

RESULTS

Eight of 19 trials met eligibility criteria and agreed to participate. Patient-level data were available from 770 participants (412 HCQ/CQ vs 358 control). Baseline characteristics were similar between groups. We did not find evidence of a difference in COVID-19 ordinal scores between days 28 and 35 post-enrollment in the pooled patient population (odds ratio, 0.97; 95% credible interval, 0.76-1.24; higher favors HCQ/CQ), and found no convincing evidence of meaningful treatment effect heterogeneity among prespecified subgroups. Adverse event and serious adverse event rates were numerically higher with HCQ/CQ vs control (0.39 vs 0.29 and 0.13 vs 0.09 per patient, respectively).

CONCLUSIONS

The findings of this individual participant data meta-analysis reinforce those of individual RCTs that HCQ/CQ is not efficacious for treatment of COVID-19 in hospitalized patients.

Hydroxychloroquine/chloroquine for the treatment of hospitalized patients with COVID-19: An individual participant data meta-analysis

Background

Results from observational studies and randomized clinical trials (RCTs) have led to the consensus that hydroxychloroquine (HCQ) and chloroquine (CQ) are not effective for COVID-19 prevention or treatment. Pooling individual participant data, including unanalyzed data from trials terminated early, enables more detailed investigation of the efficacy and safety of HCQ/CQ among subgroups of hospitalized patients.

Methods

We searched ClinicalTrials.gov in May and June 2020 for US-based RCTs evaluating HCQ/CQ in hospitalized COVID-19 patients in which the outcomes defined in this study were recorded or could be extrapolated. The primary outcome was a 7-point ordinal scale measured between day 28 and 35 post enrollment; comparisons used proportional odds ratios. Harmonized de-identified data were collected via a common template spreadsheet sent to each principal investigator. The data were analyzed by fitting a prespecified Bayesian ordinal regression model and standardizing the resulting predictions.

Results

Eight of 19 trials met eligibility criteria and agreed to participate. Patient-level data were available from 770 participants (412 HCQ/CQ vs 358 control). Baseline characteristics were similar between groups. We did not find evidence of a difference in COVID-19 ordinal scores between days 28 and 35 post-enrollment in the pooled patient population (odds ratio, 0.97; 95% credible interval, 0.76-1.24; higher favors HCQ/CQ), and found no convincing evidence of meaningful treatment effect heterogeneity among prespecified subgroups. Adverse event and serious adverse event rates were numerically higher with HCQ/CQ vs control (0.39 vs 0.29 and 0.13 vs 0.09 per patient, respectively).

Conclusions

The findings of this individual participant data meta-analysis reinforce those of individual RCTs that HCQ/CQ is not efficacious for treatment of COVID-19 in hospitalized patients.

Efficacy and safety of hydroxychloroquine in healthcare professionals with mild SARS-CoV-2 infection: Prospective, non-randomized trial

OBJECTIVES

To assess the efficacy and safety of hydroxychloroquine (HCQ) compared with no treatment in healthcare workers with mild SARS-CoV-2 infection.

METHODS

Prospective, non-randomized study. All health professionals with confirmed COVID-19 between April 7 and May 6, 2020, non-requiring initial hospitalization were asked to participate. Patients who accepted treatment were given HCQ for five days (loading dose of 400mg q12h the first day followed by200mg q12h). Control group included patients with contraindications for HCQ or who rejected treatment. Study outcomes were negative conversion and viral dynamics of SARS-CoV-2, symptoms duration and disease progression.

RESULT

Overall, 142 patients were enrolled: 87 in treatment group and 55 in control group. The median age was 37 years and 75% were female, with few comorbidities. There were no significant differences in time to negative conversion of PCR between both groups. The only significant difference in the probability of negative conversion of PCR was observed at day 21 (18.7%, 95%CI 2.0-35.4). The decrease of SARS-CoV-2 viral load during follow-up was similar in both groups. A non significant reduction in duration of some symptoms in HCQ group was observed. Two patients with HCQ and 4 without treatment developed pneumonia. No patients required admission to the Intensive Care Unit or died. About 50% of patients presented mild side effects of HCQ, mainly diarrhea.

CONCLUSIONS

Our study failed to show a substantial benefit of HCQ in viral dynamics and in resolution of clinical symptoms in health care workers with mild COVID-19.

Off-Label Use of Hydroxychloroquine in COVID-19: Analysis of Reports of Suspected Adverse Reactions From the Italian National Network of Pharmacovigilance

This study aimed to characterize adverse drug reactions (ADRs) to hydroxychloroquine in the setting of COVID-19, occurring in Italy in the period March to May 2020. The analysis of the combination therapy with azithromycin or/and lopinavir/ritonavir as well as a comparison with ADRs reported throughout 2019 was performed. ADRs collected by the Italian National Network of Pharmacovigilance were analyzed for their incidence, seriousness, outcome, coadministered drugs, and Medical Dictionary for Regulatory Activities classification. A total of 306 reports were gathered for the quarter of 2020: 54% nonserious and 46% serious, and half of the latter required either the hospitalization or its prolongation. However, most of them were either completely recovered (26%) or in the process of recovery (45%), except for 9 fatal cases. Throughout 2019, 38 reports were collected, 53% nonserious and 47% serious, but no deaths had been reported. Diarrhea, prolonged QT interval, and hypertransaminasemia were the most frequently ADRs reported in 2020, significantly higher than 2019 and specific for COVID-19 subjects treated with hydroxychloroquine. The logistic regression analyses demonstrated that the likelihood of serious ADRs, QT prolongation, and diarrhea significantly increased with hydroxychloroquine dosage. Coadministration of lopinavir/ritonavir and hydroxychloroquine showed a positive correlation with diarrhea and hypertransaminasemia and a negative relationship with the ADR seriousness. The combination therapy with azithromycin was another independent predictor of a serious ADR. Off-label use of hydroxychloroquine for COVID-19, alone or in combination regimens, was associated with increased incidence and/or seriousness of specific ADRs in patients with additional risk factors caused by the infection.

Can anti-parasitic drugs help control COVID-19?

Novel COVID-19 is a public health emergency that poses a serious threat to people worldwide. Given the virus spreading so quickly, novel antiviral medications are desperately needed. Repurposing existing drugs is the first strategy. Anti-parasitic drugs were among the first to be considered as a potential treatment option for this disease. Even though many papers have discussed the efficacy of various anti-parasitic drugs in treating COVID-19 separately, so far, no single study comprehensively discussed these drugs. This study reviews some anti-parasitic recommended drugs to treat COVID-19, in terms of function and in vitro as well as clinical results. Finally, we briefly review the advanced techniques, such as artificial intelligence, that have been used to find effective drugs for the treatment of COVID-19.

Assessment of Recovery Time, Worsening, and Death among Inpatients and Outpatients with COVID-19, Treated with Hydroxychloroquine or Chloroquine plus Azithromycin Combination in Burkina Faso

OBJECTIVES

Our study aimed to assess the statistical relationship between the use of chloroquine phosphate or hydroxychloroquine plus azithromycin (CQ/HCQ + AZ) and virological recovery, disease worsening, and death among out- and inpatients with COVID-19 in Burkina Faso.

METHODS AND DESIGNS

This was a retrospective observational study that compared outcomes in terms of time to recovery, worsening, and death in patients who received CQ/HCQ + AZ and those who did not using a multivariable Cox or Poisson model before and after propensity matching.

RESULTS

Of the 863 patients included in the study, about 50% (432/863) were home-based follow-up patients and 50% were inpatients. Of these, 83.3% (746/863) received at least 1 dose of CQ/HCQ + AZ and 13.7% (118/863) did not. There were no significant differences in associated time to recovery for patients receiving any CQ/HCQ + AZ (adjusted HR 1.44; 95% CI 0.76-2.71). Similarly, there was no significant association between CQ/HCQ + AZ use and worsening (adjusted IRR 0.80; 95% CI 0.50-1.50). However, compared with the untreated group, the treated group had a lower risk of death (adjusted HR 0.20; 95% CI 0.10-0.44).

CONCLUSIONS

The study provided valuable additional information on the use of CQ/HCQ in patients with COVID-19 and did not show any harmful outcomes of CQ/HCQ + AZ treatment.

Organoid technology and lung injury mouse models evaluating effects of hydroxychloroquine on lung epithelial regeneration

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) damages lung epithelial stem/progenitor cells. Ideal anti-SARS-CoV-2 drug candidates should be screened to prevent secondary injury to the lungs. Here, we propose that in vitro three-dimensional organoid and lung injury repair mouse models are powerful models for the screening antiviral drugs. Lung epithelial progenitor cells, including airway club cells and alveolar type 2 (AT2) cells, were co-cultured with supportive fibroblast cells in transwell inserts. The organoid model was used to evaluate the possible effects of hydroxychloroquine, which is administered as a symptomatic therapy to COVID-19 patients, on the function of mouse lung stem/progenitor cells. Hydroxychloroquine was observed to promote the self-renewal of club cells and differentiation of ciliated and goblet cells in vitro. Additionally, it inhibited the self-renewal ability of AT2 cells in vitro. Naphthalene- or bleomycin-induced lung injury repair mouse models were used to investigate the in vivo effects of hydroxychloroquine on the regeneration of club and AT2 cells, respectively. The naphthalene model indicated that the proliferative ability and differentiation potential of club cells were unaffected in the presence of hydroxychloroquine. The bleomycin model suggested that hydroxychloroquine had a limited effect on the proliferation and differentiation abilities of AT2 cells. These findings suggest that hydroxychloroquine has limited effects on the regenerative ability of epithelial stem/progenitor cells. Thus, stem/progenitor cell-derived organoid technology and lung epithelial injury repair mouse models provide a powerful platform for drug screening, which could possibly help end the pandemic.

Tocilizumab and COVID-19: Timing of Administration and Efficacy

Elevated concentrations of interleukin-6 have been demonstrated to be an important key factor in COVID-19 host immune impairment. It represents an important prognostic factor of harm associated with COVID-19 infection by stimulating a vigorous proinflammatory response, leading to the so-called “cytokine storm”. Therefore, immunomodulatory interventions targeting interleukin-6 receptor antagonism have been investigated as potential treatments to counterbalance the host immune dysregulation and to support the advantageous effects of corticosteroids. Tocilizumab is a recombinant humanized monoclonal antibody that has gained much interest during the COVID-19 pandemic as an interleukin-6 receptor antagonist. Various early observational studies have reported beneficial effects of tocilizumab. Moreover, consequent randomized controlled trials have subsequently shown significant positive results about tocilizumab efficacy and safety, focusing on outcomes like mortality, risk of intensive care unit admission, and the need for mechanical ventilation, while others presented conflicting findings. In this review, we first described the pathophysiology of COVID-19 infection while highlighting the role of interleukin-6. Furthermore, we also discussed the non-conclusive evidence about tocilizumab to be used as the standard of care therapy for all patients with COVID-19 pneumonia, as well as its beneficial effects in selected patients.

Outside any therapeutic trial prescription of hydroxychloroquine for hospitalized patients with covid-19 during the first wave of the pandemic: A national inquiry of prescription patterns among French hospitalists

INTRODUCTION

During the first wave of the coronavirus-disease 2019 (covid-19) pandemic in early 2020, hydroxychloroquine (HCQ) was widely prescribed in light of in vitro activity against severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). Our objective was to evaluate in early 2020 the rate of French hospitalists declaring having prescribed HCQ to treat covid-19 patients outside any therapeutic trial, compare the reasons and the determinants for having prescribed HCQ or not.

MATERIAL AND METHODS

A national inquiry submitted by email from May 7 to 25, 2020, to a sample of French hospitalists: doctors managing patients hospitalized for covid-19 in a French department of internal medicine or infectious diseases and identified in the directories of French hospitals or as a member of the French Infectious Diseases Society (SPILF). Primary outcome was the percentage of hospitalists declaring having prescribed HCQ to covid-19 patients. Secondary outcomes were reasons and determinants of HCQ prescription.

RESULTS

Among 400 (22.8%) responding hospitalists, 45.3% (95% CI, 40.4 to 50.1%) declared having prescribed HCQ to covid-19 patients. Two main profiles were discerned: HCQ prescribers who did not raise its efficacy as a motive, and non-prescribers who based their decision on evidence-based medicine. Multivariate analysis retained the following prescription determinants (adjusted odds ratio; 95% confidence interval): a departmental procedure for HCQ prescription (8.25; 4.79 to 14.20), having prescribed other treatments outside a therapeutic trial (3.21; 1.81 to 5.71), prior HCQ prescription (2.75; 1.5 to 5.03) and HCQ prescribed within the framework of a therapeutic trial (0.56; 0.33 to 0.95).

CONCLUSION

Almost half of the hospitalists prescribed HCQ. The physician's personality (questioning or not evidence-based-medicine principles in the context of the pandemic) and departmental therapeutic procedures were the main factors influencing HCQ prescription. Establishment of "therapeutic" procedures represents a potential means to improve the quality of therapeutic decision-making during a pandemic.

Translational Modeling of Chloroquine and Hydroxychloroquine Dosimetry in Human Airways for Treating Viral Respiratory Infections

Purpose

Chloroquine and hydroxychloroquine are effective against respiratory viruses in vitro. However, they lack antiviral efficacy upon oral administration. Translation of in vitro to in vivo exposure is necessary for understanding the disconnect between the two to develop effective therapeutic strategies.

Methods

We employed an in vitro ion-trapping kinetic model to predict the changes in the cytosolic and lysosomal concentrations of chloroquine and hydroxychloroquine in cell lines and primary human airway cultures. A physiologically based pharmacokinetic model with detailed respiratory physiology was used to predict regional airway exposure and optimize dosing regimens.

Results

At their reported in vitro effective concentrations in cell lines, chloroquine and hydroxychloroquine cause a significant increase in their cytosolic and lysosomal concentrations by altering the lysosomal pH. Higher concentrations of the compounds are required to achieve similar levels of cytosolic and lysosomal changes in primary human airway cells in vitro. The predicted cellular and lysosomal concentrations in the respiratory tract for in vivo oral doses are lower than the in vitro effective levels. Pulmonary administration of aerosolized chloroquine or hydroxychloroquine is predicted to achieve high bound in vitro-effective concentrations in the respiratory tract, with low systemic exposure. Achieving effective cytosolic concentrations for activating immunomodulatory effects and adequate lysosomal levels for inhibiting viral replication could be key drivers for treating viral respiratory infections.

Conclusion

Our analysis provides a framework for extrapolating in vitro effective concentrations of chloroquine and hydroxychloroquine to in vivo dosing regimens for treating viral respiratory infections.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s11095-021-03152-3.

LC-MS/MS Method for Determination of Hydroxychloroquine and Metabolites: Application in a Pharmacokinetic Study

Hydroxychloroquine (HCQ) was originally used as an antimalarial and immunomodulation drug. We developed and validated a simple and sensitive ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method for simultaneous quantitation of HCQ and its three metabolites in rat blood, and reported their pharmacokinetic parameters. The chromatographic separation and detection of analytes were achieved within 4 min on ZORBAX SB-C₈ (3.5 μm, 2.1 × 150 mm) column with gradient elution, and the flow rate was 0.25 mL/min. Simple protein precipitation was successfully applied for sample pretreatment. The HCQ displays a good linearity in the range of 2.0-5000.0 ng/mL, and the three metabolites also show good linearity ranging from 1.0 to 2500.0 ng/mL, with all correlation coefficients (R ²) better than 0.98. In conclusion, this rapid, sensitive method was successfully developed, validated, and then applied to a pharmacokinetic study of HCQ in rat model in high dose. The results of the pharmacokinetic study presented an average half-life time 21.14 ± 10.31 h (mean ± SD) of HCQ, which is much shorter in human compared to that in mice. For the three metabolites, longer half-life times (approximately 100 h) were shown in rat.

Cardiovascular Involvement in Patients with 2019 Novel Coronavirus Disease

2019 novel coronavirus disease (COVID-19) is caused by the infection of severe acute respiratory syndrome novel coronavirus (SARS-CoV-2). It is characterized by substantial respiratory symptoms and complicated with widespread other organ injuries. Cardiovascular impairment is one of the notable extrapulmonary manifestations, in terms of the deterioration of pre-existing cardiovascular diseases and newly onset acute events. We hereby review the high-quality reports about cardiovascular involvement in COVID-19 and summarize the main clinical characteristics of cardiac relevance for the all the first line clinical physicians. Additionally, the possible underlying mechanisms and the rationale for the application of specific medications, such as renin-angiotensin-aldosterone system inhibitors and hydroxychloroquine are also discussed.

Effects of hydroxychloroquine and favipiravir on clinical course in outpatients with COVID-19

Background/aim

Due to the importance of early outpatient treatment to prevent hospitalization and disease progression, we examined the effects of hydroxychloroquine and favipiravir, which were initiated in early period, on the clinical course of COVID-19 outpatients.

Materials and methods

Data of confirmed COVID-19 outpatients over a 4-month period were analyzed retrospectively. Public Health Management System (HSYS) was used for the case-based follow-up. Patients on antiviral therapy for at least five days, including hydroxychloroquine and / or favipiravir and patients who were followed-up for 30 days were included in this analysis.

Results

We enrolled 1489 patients in this study. Overall, 775 (52%) patients were male and a mean age of patients was 38.9 ± 11.1 years. Of these patients, 537 of them were received favipiravir, 545 of them were received hydroxychloroquine and 407 of them were received both favipiravir and hydroxychloroquine. Symptoms improvement on the 14th day of follow-up was 1.8 times higher in the group of patients receiving hydroxychloroquine compared to patients who received favipiravir (p = 0.003). On the 3rd day of follow- up, PCR negativity rate was higher in patients who received hydroxychloroquine (p = 0.004). Hospitalization rates were similar in patients receiving favipiravir and hydroxychloroquine (p = 0.144). However, in the presence of pneumonia at the time of diagnosis, the hospitalization rate was 6.6 times higher in patients who received favipiravir than those who received hydroxychloroquine.

Conclusion

The subgroups of patients treated with hydroxychloroquine and/or favipiravir did not have similar disease severities in our study. Therefore, further studies with homogeneous patient groups to be arranged prospectively are needed.

The Renin-Angiotensin System: A Key Role in SARS-CoV-2-Induced COVID-19

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), was first identified in Eastern Asia (Wuhan, China) in December 2019. The virus then spread to Europe and across all continents where it has led to higher mortality and morbidity, and was declared as a pandemic by the World Health Organization (WHO) in March 2020. Recently, different vaccines have been produced and seem to be more or less effective in protecting from COVID-19. The renin-angiotensin system (RAS), an essential enzymatic cascade involved in maintaining blood pressure and electrolyte balance, is involved in the pathogenicity of COVID-19, since the angiotensin-converting enzyme II (ACE2) acts as the cellular receptor for SARS-CoV-2 in many human tissues and organs. In fact, the viral entrance promotes a downregulation of ACE2 followed by RAS balance dysregulation and an overactivation of the angiotensin II (Ang II)-angiotensin II type I receptor (AT1R) axis, which is characterized by a strong vasoconstriction and the induction of the profibrotic, proapoptotic and proinflammatory signalizations in the lungs and other organs. This mechanism features a massive cytokine storm, hypercoagulation, an acute respiratory distress syndrome (ARDS) and subsequent multiple organ damage. While all individuals are vulnerable to SARS-CoV-2, the disease outcome and severity differ among people and countries and depend on a dual interaction between the virus and the affected host. Many studies have already pointed out the importance of host genetic polymorphisms (especially in the RAS) as well as other related factors such age, gender, lifestyle and habits and underlying pathologies or comorbidities (diabetes and cardiovascular diseases) that could render individuals at higher risk of infection and pathogenicity. In this review, we explore the correlation between all these risk factors as well as how and why they could account for severe post-COVID-19 complications.

Efficacy of chloroquine and hydroxychloroquine for the treatment of hospitalized COVID-19 patients: a meta-analysis

Aims: To evaluate the efficacy and safety of hydroxychloroquine/chloroquine, with or without azithromycin, in treating hospitalized COVID-19 patients. Materials & methods: Data from randomized and observational studies were included in a random-effects meta-analysis. Primary outcomes included time to negative conversion of SARS-CoV-2 tests, length of stay, mortality, incidence of mechanical ventilation, time to normalization of body temperature, incidence of adverse events and incidence of QT prolongations. Results: Fifty-one studies (n = 61,221) were included. Hydroxychloroquine/chloroquine showed no efficacy in all primary efficacy outcomes, but was associated with increased odds of QT prolongations. Conclusion: Due to a lack of efficacy and increased odds of cardiac adverse events, hydroxychloroquine/chloroquine should not be used for treating hospitalized COVID-19 patients.

In silico identification of SARS-CoV-2 cell entry inhibitors from selected natural antivirals

The aim of this study is to identify potential drug-like molecules against SARS-CoV-2 virus among the natural antiviral compounds published in the Encyclopedia of Traditional Chinese Medicine. To test inhibition capability of these compounds first, we docked them with Spike protein, angiotensin-converting enzyme 2 (ACE2) (PDB ID: 6M0J) and neuropilin 1 (NRP1) (PDB ID: 7JJC) receptors, and found significant docking scores with extra precision up to -11 kcal/mol. Then, their stability in the binding pockets were further evaluated with molecular dynamics simulation. Eight natural antiviral compounds were identified as potential inhibitors against SARS-CoV-2 cell entry after 200 ns molecular dynamics simulations. We found CMP-3, CMP-4, CMP-5, CMP-6 and CMP-8 are strong binders for the spike protein, CMP-1, CMP-2, CMP-4, CMP-5 and CMP-7 are strong binders for the neuropilin receptor, and CMP-5 is a strong binder for the ACE2. Quercetin derivatives (CMP-4, CMP-5, CMP-6 and CMP-7) were found highly stable in the active domain of NRP1, ACE2 and Spike protein. Especially, CMP-5 showed an inhibitory activity for all targets. These natural antivirals may be potential drug candidates for the prevention of SARS-CoV-2 infection.

Hydroxychloroquine and mortality in COVID-19 patients: a systematic review and a meta-analysis of observational studies and randomized controlled trials

Background: Hydroxychloroquine (HCQ) was proposed as potential treatment for COVID-19, but its association with mortality is unclear. We reviewed published literature for evidence of an association between HCQ (with or without azithromycin (AZM)) and total mortality in COVID-19 patients.Methods: Articles were retrieved until April 29th, 2021 by searching in seven databases. Data were combined using the general-variance-based method.Results: A total of 25 cohort studies (N=41,339 patients) and 11 randomized clinical trials (RCTs; N=8,709) were found. The use of HCQ was not associated with mortality in meta-analysis of RCTs (pooled risk ratio (PRR): 1.08, 95%CI: 0.97-1.20; I2=0%), but it was associated with 20% lower mortality risk (PRR=0.80, 95%CI: 0.69-0.93; I2=80%) in pooling of cohort studies. The negative association with mortality was mainly apparent by pooling cohort studies that used lower doses of HCQ (≤400 mg/day; PRR=0.69, 95%CI: 0.57-0.87). Use of HCQ+AZM (11 studies) was associated with 25% non-statistically significant lower mortality risk (PPR=0.75; 0.51-1.10; P=0.15). Use of HCQ was not associated with severe adverse events (PRR=1.12, 95%CI: 0.88-1.44; I2=0%).Conclusions: HCQ use was not associated with mortality in COVID-19 patients in pooling results from RCTs (high level of certainty of evidence), but it was associated with 20% mortality reduction when findings from observational studies were combined (low level of certainty of evidence). The reduction of mortality was mainly apparent in observational studies where lower doses of HCQ were used. These findings might help disentangling the debate on HCQ use in COVID-19.

COVID-19: potential therapeutics for pediatric patients

The global spread of COVID-19 has imparted significant economic, medical, and social burdens. Like adults, children are affected by this pandemic. However, milder clinical symptoms are often experienced by them. Only a minimal proportion of the affected patients may develop severe and complicated COVID-19. Supportive treatment is recommended in all patients. Antiviral and immunomodulatory medications are spared for hospitalized children with respiratory distress or severe to critical disease. Up till now, remdesivir is the only USFDA-approved anti-COVID-19 medication indicated in the majority of symptomatic patients with moderate to severe disease. Dexamethasone is solely recommended in patients with respiratory distress maintained on oxygen or ventilatory support. The use of these medications in pediatric patients is founded on evidence deriving from adult studies. No randomized controlled trials (RCTs) involving pediatric COVID-19 patients have assessed these medications' efficacy and safety, among others. Similarly, three novel monoclonal anti-SARS-CoV-2 spike protein antibodies, bamlanivimab, casirivimab and imdevimab, have been recently authorized by the USFDA. Nonetheless, their efficacy has not been demonstrated by multiple RCTs. In this review, we aim to dissect the various potential therapeutics used in children with COVID-19. We aspire to provide a comprehensive review of the available evidence and display the mechanisms of action and the pharmacokinetic properties of the studied therapeutics. Our review offers an efficient and practical guide for treating children with COVID-19.

Hydroxychloroquine/chloroquine in patients with COVID-19 in Wuhan, China: a retrospective cohort study

Background

Since the COVID-19 pandemic, several therapeutic agents have been used in COVID-19 management. However, the results were controversial. Here, we aimed to evaluate the efficacy and safety of hydroxychloroquine (HCQ)/chloroquine (CQ) in COVID-19.

Methods

We retrospectively reviewed the medical charts of patients with COVID-19 admitted to an inpatient ward in Wuhan from 2020/Feb/08 to 2020/Mar/05. Patients with HCQ/CQ and age, gender, disease severity matched ones without HCQ/CQ were selected at a 1:2 ratio. The clinical, laboratory and imaging findings were compared between these two groups. The multivariate linear regression analysis was performed to identify the factors that might influence patients’ virus shedding periods (VSPs).

Results

A total of 14 patients with HCQ/CQ and 21 matched ones were analyzed. The HCQ/CQ treatment lasted for an average of 10.36 ± 3.12 days. The mean VSPs were longer in the HCQ/CQ treatment group (26.57 ± 10.35 days vs. 19.10 ± 7.80 days, P = 0.020). There were 3 patients deceased during inpatient period, two patients were with HCQ/CQ treatment (P = 0.551). In the multivariate linear regression analysis, disease durations at admission (t = 3.643, P = 0.001) and HCQ/CQ treatment (t = 2.637, P = 0.013) were independent parameters for patients’ VSPs. One patient with CQ had recurrent first-degree atrioventricular block (AVB) and obvious QTc elongation, another one complained about dizziness and blurred vision which disappeared after CQ discontinuation. One patient with HCQ had transient AVB.

Conclusions

In summary, we identify that the HCQ/CQ administration is not related to less mortality cases at later phase of COVID-19. More studies are needed to explore whether HCQ/CQ treatment would lead to SARS-Cov-2 RNA clearance delay or not.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06477-x.

COVID-19 challenges and its therapeutics

COVID-19, an infectious disease, has emerged as one of the leading causes of death worldwide, making it one of the severe public health issues in recent decades. nCoV, the novel SARS coronavirus that causes COVID-19, has brought together scientists in the quest for possible therapeutic and preventive measures. The development of new drugs to manage COVID-19 effectively is a challenging and time-consuming process, thus encouraging extensive investigation of drug repurposing and repositioning candidates. Several medications, including remdesivir, hydroxychloroquine, chloroquine, lopinavir, favipiravir, ribavirin, ritonavir, interferons, azithromycin, capivasertib and bevacizumab, are currently under clinical trials for COVID-19. In addition, several medicinal plants with considerable antiviral activities are potential therapeutic candidates for COVID-19. Statistical data show that the pandemic is yet to slow down, and authorities are placing their hopes on vaccines. Within a short period, four types of vaccines, namely, whole virus, viral vector, protein subunit, and nucleic acid (RNA/DNA), which can confer protection against COVID-19 in different ways, were already in a clinical trial. SARS-CoV-2 variants spread is associated with antibody escape from the virus Spike epitopes, which has grave concerns for viral re-infection and even compromises the effectiveness of the vaccines. Despite these efforts, COVID-19 treatment is still solely based on clinical management through supportive care. We aim to highlight the recent trends in COVID-19, relevant statistics, and clinical findings, as well as potential therapeutics, including in-line treatment methods, preventive measures, and vaccines to combat the prevalence of COVID-19.

The Effect of COVID-19 on NF-κB and Neurological Manifestations of Disease

The coronavirus disease that presumably began in 2019 (COVID-19) is a highly infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has resulted in a pandemic. Initially, COVID-19 was thought to only affect respiration. However, accumulating evidence shows a wide range of neurological symptoms are also associated with COVID-19, such as anosmia/ageusia, headaches, seizures, demyelination, mental confusion, delirium, and coma. Neurological symptoms in COVID-19 patients may arise due to a cytokine storm and a heighten state of inflammation. The nuclear factor kappa-light-chain enhancer of activated B cells (NF-κB) is a central pathway involved with inflammation and is shown to be elevated in a dose-dependent matter in response to coronaviruses. NF-κB has a role in cytokine storm syndrome, which is associated with greater severity in COVID-19-related symptoms. Therefore, therapeutics that reduce the NF-κB pathway should be considered in the treatment of COVID-19. Neuro-COVID-19 units have been established across the world to examine the neurological symptoms associated with COVID-19. Neuro-COVID-19 is increasingly becoming an accepted term among scientists and clinicians, and interdisciplinary teams should be created to implement strategies for treating the wide range of neurological symptoms observed in COVID-19 patients.

Hydroxychloroquine (HCQ) decreases the benefit of anti-PD-1 immune checkpoint blockade in tumor immunotherapy

Immunotherapy using checkpoint blockade (ICB) with antibodies such as anti-PD-1 has revolutionised the treatment of many cancers. Despite its use to treat COVID-19 patients and autoimmune diseases such as systemic lupus erythematosus and rheumatoid arthritis, the effect of hydroxychloroquine (HCQ) on cancer immunotherapy has not been examined. In this study, remarkably, we find that HCQ alone, or in combination with azithromycin (AZ), at doses used to treat patients, decreased the therapeutic benefit of anti-PD-1 in cancer immunotherapy. No deleterious effect was seen on untreated tumors. Mechanistically, HCQ and HCQ/AZ inhibited PD-L1 expression on tumor cells, while specifically targeting the anti-PD-1 induced increase in progenitor CD8+CD44+PD-1+TCF1+ tumor infiltrating T cells (TILs) and the generation of CD8+CD44+PD-1+ effectors. Surprisingly, it also impaired the appearance of a subset of terminally exhausted CD8+ TILs. No effect was seen on the presence of CD4+ T cells, FoxP3+ regulatory T cells (Tregs), thymic subsets, B cells, antibody production, myeloid cells, or the vasculature of mice. This study indicates for the first time that HCQ and HCQ/AZ negatively impact the ability of anti-PD-1 checkpoint blockade to promote tumor rejection.

Disentangling the Association of Hydroxychloroquine Treatment with Mortality in Covid-19 Hospitalized Patients through Hierarchical Clustering

The efficacy of hydroxychloroquine (HCQ) in treating SARS-CoV-2 infection is harshly debated, with observational and experimental studies reporting contrasting results. To clarify the role of HCQ in Covid-19 patients, we carried out a retrospective observational study of 4,396 unselected patients hospitalized for Covid-19 in Italy (February–May 2020). Patients' characteristics were collected at entry, including age, sex, obesity, smoking status, blood parameters, history of diabetes, cancer, cardiovascular and chronic pulmonary diseases, and medications in use. These were used to identify subtypes of patients with similar characteristics through hierarchical clustering based on Gower distance. Using multivariable Cox regressions, these clusters were then tested for association with mortality and modification of effect by treatment with HCQ. We identified two clusters, one of 3,913 younger patients with lower circulating inflammation levels and better renal function, and one of 483 generally older and more comorbid subjects, more prevalently men and smokers. The latter group was at increased death risk adjusted by HCQ (HR[CI95%] = 3.80[3.08-4.67]), while HCQ showed an independent inverse association (0.51[0.43-0.61]), as well as a significant influence of cluster∗HCQ interaction (p < 0.001). This was driven by a differential association of HCQ with mortality between the high (0.89[0.65-1.22]) and the low risk cluster (0.46[0.39-0.54]). These effects survived adjustments for additional medications in use and were concordant with associations with disease severity and outcome. These findings suggest a particularly beneficial effect of HCQ within low risk Covid-19 patients and may contribute to clarifying the current controversy on HCQ efficacy in Covid-19 treatment.

Systematic review and meta-analysis of efficacy and safety of hydroxychloroquine and chloroquine in the treatment of COVID-19

Repurposed drugs like hydroxycloroquine (HCQ) and chloroquine (CQ) are being tested for potential therapeutic role in COVID-19. We aimed to evaluate efficacy and safety of HCQ and CQ in COVID-19. Using PubMed, EMBASE, medRxiv, Google Scholar, clinicaltrials.gov, electronic search was carried out to identify relevant articles till June 2020 with re-evaluation in last week of November 2020. Observational and interventional clinical studies comparing efficacy of CQ or HCQ to standard management or other drug/s for SARS-CoV-2 infection patients were included. Cochrane review manager version 5.3 was used for synthesis of meta-analysis results. For randomized controlled trials, risk of bias was assessed using Cochrane Collaboration risk of bias assessment tool, version 2.0 (ROB-2). ROBINS-I was used for quality assessment of observational studies. Overall evidence quality generated by review was graded as per GRADE Recommendation. A total of 903 studies were screened. Nineteen studies were included in synthesis of meta-analysis with total of 4,693, 1,626, and 6,491 patients in HCQ/CQ, HCQ/CQ + AZ and control groups, respectively. HCQ/CQ treatment was associated with significantly increased rates of virological cure (OR = 2.08, 95%CI = 1.36-3.17; P = 0.0007) and radiological cure (OR = 3.89, 95%CI = 1.35 - 11.23; P = 0.01) compared to control. HCQ/CQ had no difference in unadjusted mortality rate (unadjusted OR = 0.98 95% CI = 0.70-1.37, P = 0.89, random effect model) and adjusted hazard ratio for mortality (adjusted HR = 1.05, 95%CI = 0.86--1.29; P = 0.64). However, a significant increase in odds of disease progression (OR = 1.77, 95%CI = 1.46-2.13; P < 0.00001) and QT prolongation (OR = 11.15, 95%CI = 3.95-31.44; P < 0.00001) was noted. The results with HCQ/CQ and azithromycin combination were similar to HCQ/CQ mono-therapy. In the light of contemporary evidence on effectiveness of HCQ/CQ, judicious and monitored use of HCQ/CQ for treatment of COVID-19 patients is recommended in low to middle income countries with emphasis on no mortality benefit. Registration number of Systematic review. Register in PROSPERO database: cRD42020187710.

The Rise and Fall of Hydroxychloroquine with the COVID-19 Pandemic: Narrative Review of Selected Data

Since the first outbreak of Coronavirus Disease-2019 (COVID-19) in January 2020, the medical community has been pursuing effective countermeasures. Early in the pandemic, several small clinical and in vitro studies from France and China reported on the efficacy of chloroquine (CQ) and hydroxychloroquine (HCQ) against SARS-CoV-2 infections, which generated global attention towards these decades-old antimalarials (AM) and heralded numerous studies investigating their role in treating COVID-19. Despite several observational studies early in the pandemic affirming their beneficial role in treating COVID-19, 12 clinical studies reported no mortality benefits for CQ/HCQ in COVID-19 patients. The excitement over CQ/HCQ was ultimately quenched after three large randomized clinical trials, the COALITION-I trial in Brazil, the RECOVERY trial in the United Kingdom (UK), and the SOLIDARITY trial from World Health Organization (WHO) consistently reported no beneficial effects for CQ/HCQ in hospitalized COVID-19 patients. While initial studies suggested that CQ/HCQ might have a role in treating the early phases of infection, the results from three rigorously designed studies investigating their role in non-hospitalized COVID-19 patients were equivocal and inconsistent. Here we review the major social events related to the therapeutic use of CQ/HCQ in COVID-19, and the data from selected clinical studies evaluating their efficacy in hospitalized and non-hospitalized COVID-19 patients along with the major safety concerns.

Mefloquine, a Potent Anti-severe Acute Respiratory Syndrome-Related Coronavirus 2 (SARS-CoV-2) Drug as an Entry Inhibitor in vitro

Coronavirus disease 2019 (COVID-19) has caused serious public health, social, and economic damage worldwide and effective drugs that prevent or cure COVID-19 are urgently needed. Approved drugs including Hydroxychloroquine, Remdesivir or Interferon were reported to inhibit the infection or propagation of severe acute respiratory syndrome-related coronavirus 2 (SARS-CoV-2), however, their clinical efficacies have not yet been well demonstrated. To identify drugs with higher antiviral potency, we screened approved anti-parasitic/anti-protozoal drugs and identified an anti-malarial drug, Mefloquine, which showed the highest anti-SARS-CoV-2 activity among the tested compounds. Mefloquine showed higher anti-SARS-CoV-2 activity than Hydroxychloroquine in VeroE6/TMPRSS2 and Calu-3 cells, with IC₅₀ = 1.28 μM, IC₉₀ = 2.31 μM, and IC₉₉ = 4.39 μM in VeroE6/TMPRSS2 cells. Mefloquine inhibited viral entry after viral attachment to the target cell. Combined treatment with Mefloquine and Nelfinavir, a replication inhibitor, showed synergistic antiviral activity. Our mathematical modeling based on the drug concentration in the lung predicted that Mefloquine administration at a standard treatment dosage could decline viral dynamics in patients, reduce cumulative viral load to 7% and shorten the time until virus elimination by 6.1 days. These data cumulatively underscore Mefloquine as an anti-SARS-CoV-2 entry inhibitor.

Effects of Shuanghuanglian oral liquids on patients with COVID-19: a randomized, open-label, parallel-controlled, multicenter clinical trial

We conducted a randomized, open-label, parallel-controlled, multicenter trial on the use of Shuanghuanglian (SHL), a traditional Chinese patent medicine, in treating cases of COVID-19. A total of 176 patients received SHL by three doses (56 in low dose, 61 in middle dose, and 59 in high dose) in addition to standard care. The control group was composed of 59 patients who received standard therapy alone. Treatment with SHL was not associated with a difference from standard care in the time to disease recovery. Patients with 14-day SHL treatment had significantly higher rate in negative conversion of SARS-CoV-2 in nucleic acid swab tests than the patients from the control group (93.4% vs. 73.9%, P = 0.006). Analysis of chest computed tomography images showed that treatment with high-dose SHL significantly promoted absorption of inflammatory focus of pneumonia, which was evaluated by density reduction of inflammatory focus from baseline, at day 7 (mean difference (95% CI), −46.39 (−86.83 to −5.94) HU; P = 0.025) and day 14 (mean difference (95% CI), −74.21 (−133.35 to −15.08) HU; P = 0.014). No serious adverse events occurred in the SHL groups. This study illustrated that SHL in combination with standard care was safe and partially effective for the treatment of COVID-19.

Development of a chiral HPLC method for the separation and quantification of hydroxychloroquine enantiomers

Hydroxychloroquine (2-[[4-[(7-Chloroquinolin-4-yl) amino]pentyl](ethyl) amino]-ethanol, HCQ), an effective anti-malarial drug, has been tested in the clinics for potential treatment of severe coronavirus disease 2019 (COVID-19). Despite the controversy around the clinical benefits of HCQ, the existence of a chiral center in the molecule to possess two optical isomers suggests that there might be an enantiomeric difference on the treatment of COVID-19. Due to their poor resolution and the inability of quantification by previously reported methods for the analysis of HCQ enantiomers, it is necessary to develop an analytical method to achieve baseline separation for quantitative and accurate determination of the enantiomeric purity in order to compare the efficacy and toxicity profiles of different enantiomers. In this study, we developed and validated an accurate and reproducible normal phase chiral high-performance liquid chromatography (HPLC) method for the analysis of two enantiomers of HCQ, and the method was further evaluated with biological samples. With this newly developed method, the relative standard deviations of all analytes were lower than 5%, and the limits of quantification were 0.27 μg/ml, 0.34 μg/ml and 0.20 μg/ml for racemate, R- and S-enantiomer, respectively. The present method provides an essential analytical tool for preclinical and clinical evaluation of HCQ enantiomers for potential treatment of COVID-19.

Hydroxychloroquine/Chloroquine as Therapeutics for COVID-19: Truth under the Mystery

The outbreak of coronavirus disease-19 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly evolved into a global pandemic. One major challenge in the battle against this deadly disease is to find effective therapy. Due to the availability and proven clinical record of hydroxychloroquine (HCQ) and chloroquine (CQ) in various human diseases, there have been enormous efforts in repurposing these two drugs as therapeutics for COVID-19. To date, substantial amount of work at cellular, animal models and clinical trials have been performed to verify their therapeutic potential against COVID-19. However, neither lab-based studies nor clinical trials have provided consistent and convincing evidence to support the therapeutic value of HCQ/CQ in the treatment of COVID-19. In this mini review we provide a systematic summary on this important topic and aim to reveal some truth covered by the mystery regarding the therapeutic value of HCQ/CQ in COVID-19.

Quinine Inhibits Infection of Human Cell Lines with SARS-CoV-2

While vaccination campaigns are ongoing worldwide, there is still a tremendous medical need for efficient antivirals against SARS-CoV-2 infection. Among several drug candidates, chloroquine (CQN) and hydroxychloroquine (H-CQN) were tested intensively, and any contentious therapeutic effect of both has been discussed controversially in the light of severe side effects and missing efficacy. Originally, H-CQN descended from the natural substance quinine, a medicinal product used since the Middle Ages, which actually is regulatory approved for various indications. We hypothesized that quinine also exerts anti-SARS-CoV-2 activity. In Vero cells, quinine inhibited SARS-CoV-2 infection more effectively than CQN, and H-CQN and was less toxic. In human Caco-2 colon epithelial cells as well as the lung cell line A549 stably expressing ACE2 and TMPRSS2, quinine also showed antiviral activity. In consistence with Vero cells, quinine was less toxic in A549 as compared to CQN and H-CQN. Finally, we confirmed our findings in Calu-3 lung cells, expressing ACE2 and TMPRSS2 endogenously. In Calu-3, infections with high titers of SARS-CoV-2 were completely blocked by quinine, CQN, and H-CQN in concentrations above 50 µM. The estimated IC50s were ~25 µM in Calu-3, while overall, the inhibitors exhibit IC50 values between ~3.7 to ~50 µM, dependent on the cell line and multiplicity of infection (MOI). Conclusively, our data indicate that quinine could have the potential of a treatment option for SARS-CoV-2, as the toxicological and pharmacological profile seems more favorable when compared to its progeny drugs H-CQN or CQN.

A review on the clinical trials of repurposing therapeutic drugs, mechanisms and preventive measures against SARS-CoV-2

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a highly transmittable pathogenic viral infection that causes a disease known as COVID-19. It is a pandemic and public health challenge ravaging the world today. Unfortunately, with the daily increase of infected individuals, there is no known drug approved for the treatment of COVID-19. However, there are therapeutic drugs with the potentials to inhibit endocytic pathways, suppress ribonucleic acid (RNA) polymerase activities, and reduce the replication of SARS-CoV-2. These drugs modifications are aimed at reducing inflammation, time of recovery, and number of deaths. This review is aimed at providing updated information on the clinical manifestations, diagnosis, preventive measures and therapeutic drugs used against SARS-CoV-2. The finding of this review revealed that some of these drugs are transmembrane protease, serine 2, and angiotensin-converting enzyme 2 inhibitors with the capacity to block the entrance/replication of SARS-CoV-2 in a host cell and therefore, may be promising in preventing the spread and mortality of SARS-CoV-2. However, these drugs may cause detrimental health effects such as toxic and non-efficacy issues. Therefore great caution should be employed by health professionals when prescribing these drugs to COVID-19 patients.

A Narrative Review of Antiviral Drugs Used for COVID-19 Pharmacotherapy

PURPOSE

A number of research articles has been published evaluating safety and efficacy of drugs against COVID-19. This study was undertaken to collate and review the information regarding common proposed anti- viral drugs for easy reference.

METHODS

The literature was search was done using terms like severe acute respiratory syndrome or SARS-CoV-2 or 2019-nCoV or SARS-CoV or COVID-19 in combination with drugs or treatment or pharmaco-therapy using PubMed and google scholar to identify relevant articles.

RESULTS

Despite showing good early results, hydroxychloroquine and lopinavir-ritonavir has not shown clinical benefit in randomized controlled trials. However lopinavir in combination with other drugs specially interferon is being investigated. Remdesivir has shown positive effect in terms of clinical improvement and continued to being investigated alone or in combination with other drugs. Favipiravir has shown mixed results and more data from adequately powered study is needed to prove its efficacy.

CONCLUSIONS

Many drugs which showed positive effect in initial studies could not replicate the same benefit in large randomized controlled trials. There is need to evaluate efficacy and safety of drugs based on high quality evidence before allowing it to be used in general population.

The efficacy and safety of hydroxychloroquine (HCQ) in treatment of COVID19 -a systematic review and meta-analysis

INTRODUCTION

The treatment of SARS CoV2 (Severe Acute Respiratory Syndrome corona virus 2) also known as COVID-19 (corona virus disease 2019) continues to remain an enigma even after six months of the pandemic. Hydroxychloroquine (HCQ) has been one of the most widely tested drugs for SARS CoV2 on account of its antiviral properties. However the results so far have been far from categorical. The meta-analyses conducted till date are also lacking in precision and appropriateness. This systematic review and meta-analysis addresses the efficacy and safety of HCQ in SARS CoV2 by overcoming the limitations of earlier meta-analysis.

METHODS

A total of 5 prominent medical databases were searched and fourteen studies (n = 12455) were included in the systematic review and meta-analyses. The data on survival, alleviation of symptoms, conversion of RT PCR positivity to negativity, use and efficacy in presence of co-morbidities (Hypertension, diabetes and heart disease) and cardiac and gastrointestinal side effects were extracted. Meta-analysis was applied to calculate the pooled estimates. Fixed-effects model results were chosen since I² was <25%.Meta-analysis was conducted using STATA version 13 (StataCorp LP, College Station, TX, USA).

RESULTS

The pooled estimates showed that HCQ treatment did not significantly affect survival at 14 and 28 days in COVID-19 patients with respect to the control population (RR: 1.003, 95% CI: 0.983-1.022), alleviation of symptoms at day 10 (RR: 1.044, 95% CI: 0.911 1.196), success in presence of co-morbidities (RR: 1.058, 95% CI: 1.035-1.082) and conversion from RT PCR positive to RT PCR negative on day 6 (RR:1.123, 95% CI: 1.041 1.212). There was higher risk for cardiac side effects (RR: 2.012, 95% CI: 1.428 2.833) and gastrointestinal side effects (RR: 1.318, 95% CI: 0.730 2.380) in HCQ recipients.

CONCLUSION

There is no evidence on the safety and efficacy of HCQ either alone or in combination with other drugs in SARS CoV2 infection.

Revised Korean Society of Infectious Diseases/National Evidence-based Healthcarea Collaborating Agency Guidelines on the Treatment of Patients with COVID-19

Despite the global effort to mitigate the spread, coronavirus disease 2019 (COVID-19) has become a pandemic that took more than 2 million lives. There are numerous ongoing clinical studies aiming to find treatment options and many are being published daily. Some effective treatment options, albeit of variable efficacy, have been discovered. Therefore, it is necessary to develop an evidence-based methodology, to continuously check for new evidence, and to update recommendations accordingly. Here we provide guidelines on pharmaceutical treatment for COVID-19 based on the latest evidence.

COVID-19: Before the Fall, An Evidence-Based Narrative Review of Treatment Options

The 2019 novel coronavirus (COVID-19) has quickly become one of the most dire international pandemic crises since the 1918 Spanish flu. Evidence for COVID-19 pharmacological therapies has shown rapid growth and a diverse array of results, but an assessment of the value of each piece of evidence must be reinforced. This article aims to review utilized therapies, the evidence level supporting these therapies, as well as drugs under investigation for the treatment of COVID-19. Primary scrutinized therapies include antiviral regimens, such as remdesivir, hydroxychloroquine/chloroquine, lopinavir/ritonavir, immunomodulating drugs, such as corticosteroids and interleukin (IL) inhibitors, and other therapies including convalescent plasma. Only one therapy, dexamethasone, has shown a mortality benefit in randomized controlled trials and summarized evidence for other therapies show limited positive results. Reviewing these therapies in a historical way shows how limited evidence can drive therapy decisions. A broad summary of available evidence can assist clinicians in a return to hierarchical assessments of evidence which can lead to safer patient outcomes, improved distribution of resources, and better targets for appropriate therapy decisions.

Drug discovery and development targeting the life cycle of SARS-CoV-2

A newly emerged coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), belongs to the β-coronavirus family and shows high similarities with SARS-CoV. On March 11, 2020, the World Health Organization (WHO) declared SARS-CoV-2 a global pandemic, and the disease was named the coronavirus disease 2019 (COVID-19). The ongoing COVID-19 pandemic has caused over 46 million infections and over one million deaths worldwide, and the numbers are still increasing. Efficacious antiviral agents are urgently needed to combat this virus. The life cycle of SARS-CoV-2 mainly includes the viral attachment, membrane fusion, genomic replication, assembly and budding of virions. Accordingly, drug development against SARS-CoV-2 currently focuses on blocking spike protein binding to ACE2, inhibiting viral membrane fusion with host cells, and preventing the viral replication by targeting 3C-like protease, papain-like protease, RNA-dependent RNA polymerase as well as some host-cell proteins. In this review, the advances of drug development in these three major areas are elaborated.

From hydroxychloroquine to ivermectin: what are the anti-viral properties of anti-parasitic drugs to combat SARS-CoV-2?

BACKGROUND

Nearly a year into the COVID-19 pandemic, we still lack effective anti-SARS-CoV-2 drugs with substantial impact on mortality rates except for dexamethasone. As the search for effective antiviral agents continues, we aimed to review data on the potential of repurposing antiparasitic drugs against viruses in general, with an emphasis on coronaviruses.

METHODS

We performed a review by screening in vitro and in vivo studies that assessed the antiviral activity of several antiparasitic agents: chloroquine, hydroxychloroquine (HCQ), mefloquine, artemisinins, ivermectin, nitazoxanide (NTZ), niclosamide, atovaquone and albendazole.

RESULTS

For HCQ and chloroquine we found ample in vitro evidence of antiviral activity. Cohort studies that assessed the use of HCQ for COVID-19 reported conflicting results, but randomized controlled trials (RCTs) demonstrated no effect on mortality rates and no substantial clinical benefits of HCQ used either for prevention or treatment of COVID-19. We found two clinical studies of artemisinins and two studies of NTZ for treatment of viruses other than COVID-19, all of which showed mixed results. Ivermectin was evaluated in one RCT and few observational studies, demonstrating conflicting results. As the level of evidence of these data is low, the efficacy of ivermectin against COVID-19 remains to be proven. For chloroquine, HCQ, mefloquine, artemisinins, ivermectin, NTZ and niclosamide, we found in vitro studies showing some effects against a wide array of viruses. We found no relevant studies for atovaquone and albendazole.

CONCLUSIONS

As the search for an effective drug active against SARS-CoV-2 continues, we argue that pre-clinical research of possible antiviral effects of compounds that could have antiviral activity should be conducted. Clinical studies should be conducted when sufficient in vitro evidence exists, and drugs should be introduced into widespread clinical use only after being rigorously tested in RCTs. Such a search may prove beneficial in this pandemic or in outbreaks yet to come.