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.

Cardiotoxicity of chloroquine and hydroxychloroquine through mitochondrial pathway.

BACKGROUND: Medical therapies can cause cardiotoxicity. Chloroquine (QC) and hydroxychloroquine (HQC) are drugs used in the treatment of malaria and skin and rheumatic disorders. These drugs were considered to help treatment of coronavirus disease (COVID-19) in 2019. Despite the low cost and availability of QC and HQC, reports indicate that this class of drugs can cause cardiotoxicity. The mechanism of this event is not well known, but evidence shows that QC and HQC can cause cardiotoxicity by affecting mitochondria and lysosomes. METHODS: Therefore, our study was designed to investigate the effects of QC and HQC on heart mitochondria. In order to achieve this aim, mitochondrial function, reactive oxygen species (ROS) level, mitochondrial membrane disruption, and cytochrome c release in heart mitochondria were evaluated. Statistical significance was determined using the one-way and two-way analysis of variance (ANOVA) followed by post hoc Tukey to evaluate mitochondrial succinate dehydrogenase (SDH) activity and cytochrome c release, and Bonferroni test to evaluate the ROS level, mitochondrial membrane potential (MMP) collapse, and mitochondrial swelling. RESULTS: Based on ANOVA analysis (one-way), the results of mitochondrial SDH activity showed that the IC50 concentration for CQ is 20 µM and for HCQ is 50 µM. Based on two-way ANOVA analysis, the highest effect of CQ and HCQ on the generation of ROS, collapse in the MMP, and mitochondrial swelling were observed at 40 µM and 100 µM concentrations, respectively (p < 0.05). Also, the highest effect of these two drugs has been observed in 60 min (p < 0.05). The statistical results showed that compared to CQ, HCQ is able to cause the release of cytochrome c from mitochondria in all applied concentrations (p < 0.05). CONCLUSIONS: The results suggest that QC and HQC can cause cardiotoxicity which can lead to heart disorders through oxidative stress and disfunction of heart mitochondria.

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.

Molecular mechanisms in chloroquine-exposed muscle cells elucidated by combined proteomic and microscopic studies.

OBJECTIVES: Chloroquine (CQ) is an antimalarial drug with a growing number of applications as recently demonstrated in attempts to treat Covid-19. For decades, it has been well known that skeletal and cardiac muscle cells might display vulnerability against CQ exposure resulting in the clinical manifestation of a CQ-induced myopathy. In line with the known effect of CQ on inhibition of the lysosomal function and thus cellular protein clearance, the build-up of autophagic vacuoles along with protein aggregates is a histological hallmark of the disease. Given that protein targets of the perturbed proteostasis are still not fully discovered, we applied different proteomic and immunological-based studies to improve the current understanding of the biochemical nature of CQ-myopathy. METHODS: To gain a comprehensive understanding of the molecular pathogenesis of this acquired myopathy and to define proteins targets as well as pathophysiological processes beyond impaired proteolysis, utilising CQ-treated C2C12 cells and muscle biopsies derived from CQ-myopathy patients, we performed different proteomic approaches and Coherent Anti-Stokes Raman Scattering (CARS) microscopy, in addition to immunohistochemical studies. RESULTS: Our combined studies confirmed an impact of CQ-exposure on proper protein processing/folding and clearance, highlighted changes in the interactome of p62, a known aggregation marker and hereby identified the Rett syndrome protein MeCP2 as being affected. Moreover, our approach revealed-among others-a vulnerability of the extracellular matrix, cytoskeleton and lipid homeostasis. CONCLUSION: We demonstrated that CQ exposure (secondarily) impacts biological processes beyond lysosomal function and linked a variety of proteins with known roles in the manifestation of other neuromuscular diseases.

Safety considerations of chloroquine in the treatment of patients with diabetes and COVID-19.

Patients with underlying diseases and coronavirus disease 2019 (COVID-19) are at increased risk of death. Using the recommended anti-COVID-19 drug, chloroquine phosphate (CQ), to treat patients with severe cases and type 2 diabetes (T2D) could potentially cause harm. We aimed to understand the safety of CQ in patients with T2D by administrating the recommended dose (63 mg/kg twice daily for 7 days) and a high dose (126 mg/kg twice daily for 7 days) of CQ in T2D rats. We found that CQ increased the total mortality of the T2D rats from 27.3% to 72.7% in the recommended and high-dose groups during the whole period. CQ also induced hematotoxicity of T2D rats in the high-dose group; the hepatic enzymes in T2D rats were significantly elevated. CQ also changed the electrocardiograms, prolonged the QTc intervals, and produced urinary leukocytes and proteins in the T2D rats. Histopathological observations revealed that CQ caused severe damage to the rats' heart, jejunum, liver, kidneys, spleen, and retinas. Furthermore, CQ significantly decreased the serum IL-1ß and IL-6 levels. In conclusion, the CQ dosage and regimen used to treat COVID-19 induced adverse effects in diabetic rats, suggesting the need to reevaluate the effective dose of CQ in humans.

Novel Tetrahydroisoquinoline-Based Heterocyclic Compounds Efficiently Inhibit SARS-CoV-2 Infection In Vitro.

The ongoing COVID-19 pandemic has caused over six million deaths and huge economic burdens worldwide. Antivirals against its causative agent, SARS-CoV-2, are in urgent demand. Previously, we reported that heterocylic compounds, i.e., chloroquine (CQ) and hydroxychloroquine (HCQ), are potent in inhibiting SARS-CoV-2 replication in vitro. In this study, we discussed the syntheses of two novel heterocylic compounds: tert-butyl rel-4-(((3R,4S)-3-(1H-indol-3-yl)-1-oxo-2-propyl-1,2,3,4-tetrahydroisoquinolin-4-yl)methyl)piperazine-1-carboxylate (trans-1) and rel-(3R,4S)-3-(1H-indol-3-yl)-4-(piperazin-1-ylmethyl)-2-propyl-3,4-dihydroisoquinolin-1(2H)-one (trans-2), which effectively suppressed authentic SARS-CoV-2 replication in Vero E6 cells. Compound trans-1 showed higher anti-SARS-CoV-2 activity than trans-2, with a half maximal effective concentration (EC50) of 3.15 µM and a selective index (SI) exceeding 63.49, which demonstrated comparable potency to CQ or HCQ. Additional anti-SARS-CoV-2 tests on Calu-3 human lung cells showed that trans-1 efficiently inhibited viral replication (EC50 = 2.78 µM; SI: > 71.94) and performed better than CQ (EC50 = 44.90 µM; SI = 2.94). The time of an addition assay showed that the action mechanism of trans-1 differed from that of CQ, as it mainly inhibited the post-entry viral replication in both Vero E6 and Calu-3 cells. In addition, the differences between the antiviral mechanisms of these novel compounds and CQ were discussed.

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.

Affinity binding of COVID-19 drug candidates (chloroquine/hydroxychloroquine) and serum albumin: Based on photochemistry and molecular docking.

Chloroquine (CQ) and hydroxychloroquine (HCQ) show good efficacy in the treatment of SARS-CoV-2 in the early stage, while they are no longer recommended due to their side effects. As an important drug delivery carrier, serum albumin (SA) is closely related to the efficacy of drugs. Here, the affinity behaviour of chloroquine and hydroxychloroquine with two SA were investigated through the multispectral method of biochemistry and computer simulation. The results showed that the intrinsic emission of both SA was quenched by CQ and HCQ in a spontaneous exothermic entropy reduction static process, which relied mainly on hydrogen bonding and van der Waals forces. The lower binding constants suggested weak binding between the two drugs and SA, which might lead to differences in efficacy and possibly even to varying side effects. Binding site recognition demonstrated that CQ preferred to bind to the two sites of both SA, while HCQ tended to bind to site I of SA. The results of conformational studies demonstrated that CQ and HCQ could affect the structure of both SA by slightly increasing the α-helix content of SA. Finally, we combine the results from experimental start with molecular simulations to suggest drug modifications to guide the design of drugs. This work has important implications for guiding drug design improvements to select CQ derivatives with fewer side effects for the treatment of COVID-19.

Challenges Based on Antiplasmodial and Antiviral Activities of 7-Chloro-4-aminoquinoline Derivatives.

We report the structural functionalization of the terminal amino group of N1 -(7-chloroquinolin-4-yl) butane-1,4-diamine, leading to a series of 7-chloro-4-aminoquinoline derivatives, and their evaluation as potent anti-malarial and anti-viral agents. Some compounds exhibited promising anti-malarial effects against the Plasmodium falciparum 3D7 (chloroquine-sensitive) and Dd2 (chloroquine-resistant) strains. In addition, these compounds were assayed in vitro against influenza A virus (IAV) and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Compound 5 h, bearing an N-mesityl thiourea group, displayed pronounced anti-infectious effects against malaria, IAV, and SARS-CoV-2. These results provide new insights into drug discovery for the prevention or treatment of malaria and virus co-infection.

Comparison of the Antiviral Activity of Remdesivir, Chloroquine, and Interferon-ß as Single or Dual Agents Against the Human Beta-Coronavirus OC43.

The human beta-coronavirus strain, OC43, provides a useful model for testing the antiviral activity of various agents. We compared the activity of several antiviral drugs against OC43, including remdesivir, chloroquine, interferon (IFN)-ß, IFN-λ1, and IFN-λ4, in two distinct cell types: human colorectal carcinoma cell line (HCT-8 cells) and normal human bronchial epithelial (NHBE) cells. We also tested whether these agents mediate additive, synergistic, or antagonistic activity against OC43 infection when used in combination. When used as single agents, remdesivir exhibited stronger antiviral activity than chloroquine, and IFN-ß exhibited stronger activity than IFN-λ1 or IFN-λ4 against OC43 in both HCT-8 and NHBE cells. Anakinra (IL-1 inhibitor) and tocilizumab (IL-6 inhibitor) did not mediate any antiviral activity. The combination of IFN-ß plus chloroquine or remdesivir resulted in higher synergy scores and higher expression of IFN-stimulated genes than did IFN-ß alone. In contrast, the combination of remdesivir plus chloroquine resulted in an antagonistic interaction in NHBE cells. Our findings indicate that the combined use of IFN-ß plus remdesivir or chloroquine induces maximal antiviral activity against human coronavirus strain OC43 in primary human respiratory epithelial cells. Furthermore, our experimental OC43 virus infection model provides an excellent method for evaluating the biological activity of antiviral drugs.

Cardiac effects and toxicity of chloroquine: a short update.

There is currently increased interest in the use of the antimalarial drugs chloroquine and hydroxychloroquine for the treatment of other diseases, including cancer and viral infections such as coronavirus disease 2019 (COVID-19). However, the risk of cardiotoxic effects tends to limit their use. In this review, the effects of these drugs on the electrical and mechanical activities of the heart as well as on remodelling of cardiac tissue are presented and the underlying molecular and cellular mechanisms are discussed. The drugs can have proarrhythmic as well as antiarrhythmic actions resulting from their inhibition of ion channels, including voltage-dependent Na+ and Ca2+ channels, background and voltage-dependent K+ channels, and pacemaker channels. The drugs also exert a vagolytic effect due at least in part to a muscarinic receptor antagonist action. They also interfere with normal autophagy flux, an effect that could aggravate ischaemia/reperfusion injury or post-infarct remodelling. Most of the toxic effects occur at high concentrations, following prolonged drug administration or in the context of drug associations.

A systematic review and Bayesian network meta-analysis for comparative safety assessment of favipiravir interventions in hospitalized COVID-19 patients.

INTRODUCTION: COVID-19 is a coronavirus-based infectious illness that was first detected at the end of 2019 in Wuhan, China. The novel virus induces severe acute respiratory syndrome (SARS-CoV-2) and has spread globally, resulting in an ongoing pandemic. There is still a lack of evidence for direct comparison of favipiravir therapy. Network meta-analysis (NMA), may incorporate direct and indirect comparisons in a pooled computation while depending on strong assumptions and premises. This study provides evidence-based recommendations on the safety of currently used clinical pharmacological treatments compared to favipiravir for COVID-19 patients. METHODOLOGY: We conducted a systematic review and Bayesian NMA. We searched the primary databases and clinical trials center for reports of short-term, randomized controlled trials (RCTs) of favipiravir for COVID-19 treatment. The primary endpoints here considered were any adverse events observed or reported during the treatment cycle with estimates of odds ratio (OR) and 95% confidence interval (CI), until November 6, 2021. RESULTS: Between January 2020 and July 2021, 908 individuals were randomly assigned to one of the seven active prescription medication regimens or placebo in this study, generating seven direct comparisons on 12 data points. The safety of favipiravir over the four clinically efficacious monotherapies or combinations including tocilizumab, arbidol, lopinavir + ritonavir, and chloroquine remained unknown due to the lack of a significant difference and the limited sample size. CONCLUSIONS: Overall, comparative rankings could assist doctors and guideline developers in decision-making. We have also concluded that the safety of favipiravir requires further attention.