The arrhythmogenic cardiotoxicity of the quinoline and structurally related antimalarial drugs: a systematic review

Current trends to design antimalarial drugs targeting N-myristoyltransferase

Malaria is a disease caused by Plasmodium spp., of which Plasmodium falciparum and Plasmodium vivax are the most prevalent. Unfortunately, traditional and some current treatment regimens face growing protozoan resistance. Thus, searching for and exploring new drugs and targets is necessary. One of these is N-myristoyltransferase (NMT). This enzyme is responsible for the myristoylation of several protein substrates in eukaryotic cells, including Plasmodium spp., thus enabling the assembly of protein complexes and stabilization of protein-membrane interactions. Given the importance of this target in developing new antiparasitic drugs, this review aims to explore the recent advances in the design of antimalarial drugs to target Plasmodium NMT.

Assessing the interplay between off-target promiscuity, cytotoxicity, and tolerability in rodents to improve the safety profile of novel anti-malarial plasmepsin X inhibitors

Within drug development, high off-target promiscuity as well as potent cytotoxicity, are associated with a high attrition rate. We investigated the safety profile of novel plasmepsin X (PMX) inhibitors for the treatment of malaria. In our screening cascade, a total of 249 PMX compounds were profiled in a panel of in vitro secondary pharmacology assays containing 44 targets (SafetyScreen44 panel) and in a cytotoxicity assay in HepG2 cells using ATP as an endpoint. Six of the lead compounds were subsequently tested in a 7-d rat toxicology study, and/or in a cardiovascular study in guinea pigs. Overall, compounds with high cytotoxicity in HepG2 cells correlated with high promiscuity (off-target hit rate >20%) in the SafetyScreen44 panel and were associated with poor tolerability in vivo (decedents, morbidity, adverse clinical signs, or severe cardiovascular effects). Some side effects observed in rats or guinea pigs could putatively be linked with hits in the secondary pharmacological profiling, such as the M1 or M2 muscarinic acetylcholine receptor, opioid µ and/or κ receptors or hERG/CaV1.2/Na+ channels, which were common to >50% the compounds tested in vivo. In summary, compounds showing high cytotoxicity and high promiscuity are likely to be poorly tolerated in vivo. However, such associations do not necessarily imply a causal relationship. Identifying the targets that cause these undesirable effects is key for early safety risk assessment. A tiered approach, based on a set of in vitro assays, helps selecting the compounds with highest likelihood of success to proceed to in vivo toxicology studies.

Brugada syndrome precipitated by uncomplicated malaria treated with dihydroartemisinin piperaquine: a case report

BACKGROUND

Cardiovascular events following anti-malarial treatment are reported infrequently; only a few studies have reported adverse outcomes. This case presentation emphasizes cardiological assessment of Brugada syndrome, presenting as life-threatening arrhythmia during anti-malarial treatment. Without screening and untreated, this disease may lead to sudden cardiac death.

CASE PRESENTATION

This is a case of 23-year-old male who initially presented with palpitations followed by syncope and shortness of breath with a history of malaria. He had switched treatment from quinine to dihydroartemisinin-piperaquine (DHP). Further investigations revealed the ST elevation electrocardiogram pattern typical of Brugada syndrome, confirmed with flecainide challenge test. Subsequently, anti-malarial treatment was stopped and an Implantable Cardioverter Defibrillator (ICD) was inserted.

CONCLUSIONS

Another possible cause of arrhythmic events happened following anti-malarial consumption. This case highlights the possibility of proarrhytmogenic mechanism of malaria infection and anti-malarial drug resulting in typical manifestations of Brugada syndrome.

Should Physicians Be Aware of Rhythm Disturbances in Adults with Systemic Autoimmune Diseases and Anti-Ro52 Antibodies? A Cross-Sectional Study

Objectives: The association between anti-Ro/SSA antibodies and the appearance of cardiac rhythm disorders in adults is discussed. We aim to study this relationship, together with active treatments and comorbidities, and its impact on daily clinical practice in adults with systemic autoimmune diseases (SADs). Methods: This cross-sectional single-center study was conducted in a tertiary hospital between January 2021 and March 2022. A sample of adult patients followed up in the SAD Unit with a diagnosis of a SAD and previously tested for anti-Ro/SSA and anti-La/SSB were recruited. All of them underwent a 12-lead electrocardiogram. Results: 167 patients were included. 90 (53.9%) were positive for anti-Ro60, 101 (60.5%) for anti-Ro52, and 45 (26.9%) for anti-La/SSB; 52 (31.3%) were triple-negative. 84% were women, and the mean age was 59 years (standard deviation 12.8). The most common SAD was primary Sjögren's syndrome (34.8%), followed by systemic lupus erythematosus (24.6%) and rheumatoid arthritis (22.8%). A statistically significant relationship was found between anti-Ro52 positivity and cardiac rhythm disorders (relative risk = 2.007 [1.197-3.366]), specifically QTc prolongation (relative risk = 4.248 [1.553-11.615]). Multivariate regressions showed a significant association, with diabetes mellitus being the most related comorbidity. The association between anti-Ro52 antibodies and atrioventricular conduction disorders was not significant. Conclusions: The presence of anti-Ro52 antibodies in adult patients with SADs is associated with an increased risk of QTc prolongation. Electrocardiographic screening of patients with SAD, anti-Ro52 antibodies, and other risk factors, like diabetes mellitus or QT-prolonging drugs, seems advisable. Those with baseline electrocardiogram abnormalities or additional risk factors should undergo electrocardiographic monitoring.

Population-specific variations in KCNH2 predispose patients to delayed ventricular repolarization upon dihydroartemisinin-piperaquine therapy

Dihydroartemisinin-piperaquine is efficacious for the treatment of uncomplicated malaria and its use is increasing globally. Despite the positive results in fighting malaria, inhibition of the Kv11.1 channel (hERG; encoded by the KCNH2 gene) by piperaquine has raised concerns about cardiac safety. Whether genetic factors could modulate the risk of piperaquine-mediated QT prolongations remained unclear. Here, we first profiled the genetic landscape of KCNH2 variability using data from 141,614 individuals. Overall, we found 1,007 exonic variants distributed over the entire gene body, 555 of which were missense. By optimizing the gene-specific parametrization of 16 partly orthogonal computational algorithms, we developed a KCNH2-specific ensemble classifier that identified a total of 116 putatively deleterious missense variations. To evaluate the clinical relevance of KCNH2 variability, we then sequenced 293 Malian patients with uncomplicated malaria and identified 13 variations within the voltage sensing and pore domains of Kv11.1 that directly interact with channel blockers. Cross-referencing of genetic and electrocardiographic data before and after piperaquine exposure revealed that carriers of two common variants, rs1805121 and rs41314375, experienced significantly higher QT prolongations (ΔQTc of 41.8 ms and 61 ms, respectively, vs 14.4 ms in controls) with more than 50% of carriers having increases in QTc >30 ms. Furthermore, we identified three carriers of rare population-specific variations who experienced clinically relevant delayed ventricular repolarization. Combined, our results map population-scale genetic variability of KCNH2 and identify genetic biomarkers for piperaquine-induced QT prolongation that could help to flag at-risk patients and optimize efficacy and adherence to antimalarial therapy.

A Phosphine-Free Air-Stable Mn(II)-Catalyst for Sustainable Synthesis of Quinazolin-4(3H)-ones, Quinolines, and Quinoxalines in Water

The synthesis, characterization, and catalytic application of a new phosphine-free, well-defined, water-soluble, and air-stable Mn(II)-catalyst [Mn(L)(H2O)2Cl](Cl) ([1]Cl) featuring a 1,10-phenanthroline based tridentate pincer ligand, 2-(1H-pyrazol-1-yl)-1,10-phenanthroline (L), in dehydrogenative functionalization of alcohols to various N-heterocycles such as quinazolin-4(3H)-ones, quinolines, and quinoxalines are reported here. A wide array of multisubstituted quinazolin-4(3H)-ones were prepared in water under air following two pathways via the dehydrogenative coupling of alcohols with 2-aminobenzamides and 2-aminobenzonitriles, respectively. 2-Aminobenzyl alcohol and ketones bearing active methylene group were used as coupling partners for synthesizing quinoline derivatives, and various quinoxaline derivatives were prepared by coupling vicinal diols and 1,2-diamines. In all cases, the reaction proceeded smoothly using our Mn(II)-catalyst [1]Cl in water under air, affording the desired N-heterocycles in satisfactory yields starting from cheap and readily accessible precursors. Gram-scale synthesis of the compounds indicates the industrial relevance of our synthetic strategy. Control experiments were performed to understand and unveil the plausible reaction mechanism.

The effect of an anti-malarial herbal remedy, Maytenus senegalensis, on electrocardiograms of healthy Tanzanian volunteers

BACKGROUND

The emergence of resistance to artemisinin-based combination therapy necessitates the search for new, more potent antiplasmodial compounds, including herbal remedies. The whole extract of Maytenus senegalensis has been scientifically investigated for potential biological activities both in vitro and in vivo, demonstrating strong antimalarial activity. However, there is a lack of data on the electrocardiographic effects of M. senegalensis in humans, which is a crucial aspect in the investigation of malaria treatment. Assessing the electrocardiographic effects of M. senegalensis is essential, as many anti-malarial drugs can inadvertently prolong the QT interval on electrocardiograms. Therefore, the study's objective was to evaluate the electrocardiographic effects of M. senegalensis in healthy adult volunteers.

METHODS

This study is a secondary analysis of an open-label single-arm dose escalation. Twelve healthy eligible Tanzanian males, aged 18 to 45, were enrolled in four study dose groups. A single 12-lead electrocardiogram (ECG) was performed at baseline and on days 3, 7, 14, 28, and 56.

RESULTS

No QTcF adverse events occurred with any drug dose. Only one volunteer who received the highest dose (800 mg) of M. senegalensis experienced a moderate transient change (△QTcF > 30 ms; specifically, the value was 37 ms) from baseline on day 28. There was no difference in maximum QTcF and maximum △QTcF between volunteers in all four study dose groups.

CONCLUSIONS

A four-day regimen of 800 mg every 8 h of M. senegalensis did not impact the electrocardiographic parameters in healthy volunteers. This study suggests that M. senegalensis could be a valuable addition to malaria treatment, providing a safer alternative and potentially aiding in the battle against artemisinin-resistant malaria. The results of this study support both the traditional use and the modern therapeutic potential of M. senegalensis. They also set the stage for future research involving larger and more diverse populations to explore the safety profile of M. senegalensis in different demographic groups. This is especially important considering the potential use of M. senegalensis as a therapeutic agent and its widespread utilization as traditional medicine. Trial registration ClinicalTrials.gov, NCT04944966. Registered 30 June 2021-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT04944966?term=kamaka&draw=2&rank=1.

Triple artemisinin-based combination therapy (TACT): advancing malaria control and eradication efforts

This paper examines the far-reaching implications of Triple Artemisinin-Based Combination Therapy (TACT) in the global battle against malaria. Artemisinin-Based Combination Therapy (ACT) is recognized for its cost-effectiveness, lower likelihood of adverse events, and widespread acceptance by patients and healthcare providers. However, TACT introduces novel dimensions to the fight against malaria that make them a superior choice in several aspects. TACT has been demonstrated to address resistance, offer a broader spectrum of action, reduce the risk of treatment failure, and can be tailored to meet regional needs, strengthening the global effort to combat malaria. However, maximizing these benefits of TACT depends on accessibility, particularly in resource-limited regions where malaria is most prevalent. Collaborative efforts among stakeholders, sustainable pricing strategies, efficient supply chains, and public-private partnerships are essential to ensure that TACT reaches needy populations. Moreover, dispelling prevalent malaria myths through health education campaigns is critical in this endeavour. The paper underscores the significance of collaborative initiatives and partnerships among governments, international organizations, research institutions, acadaemia, pharmaceutical companies, and local communities. Together, these efforts can pave the way for the acceptance, adoption, and success of TACT, ultimately advancing the global goal of a malaria-free world.

Modeling policy interventions for slowing the spread of artemisinin-resistant pfkelch R561H mutations in Rwanda

Artemisinin combination therapies (ACTs) are highly effective at treating uncomplicated Plasmodium falciparum malaria, but the emergence of the new pfkelch13 R561H mutation in Rwanda, associated with delayed parasite clearance, suggests that interventions are needed to slow its spread. Using a Rwanda-specific spatial calibration of an individual-based malaria model, we evaluate 26 strategies aimed at minimizing treatment failures and delaying the spread of R561H after 3, 5 and 10 years. Lengthening ACT courses and deploying multiple first-line therapies (MFTs) reduced treatment failures after 5 years when compared to the current approach of a 3-d course of artemether-lumefantrine. The best among these options (an MFT policy) resulted in median treatment failure counts that were 49% lower and a median R561H allele frequency that was 0.15 lower than under baseline. New approaches to resistance management, such as triple ACTs or sequential courses of two different ACTs, were projected to have a larger impact than longer ACT courses or MFT; these were associated with median treatment failure counts in 5 years that were 81-92% lower than the current approach. A policy response to currently circulating artemisinin-resistant genotypes in Africa is urgently needed to prevent a population-wide rise in treatment failures.

[Mortality associated with myocardial damage by troponin I in patients with COVID 19]

Background

Coronavirus disease 2019 (COVID-19) can cause cardiac injury, probably associated with myocarditis and ischemia induced by the infection. Myocardial damage leads to the liberation of proinflammatory cytokines and to the activation of autoimmune adaptive mechanisms through molecular limitation.

Objective

To assess mortality associated with myocardial damage in hospitalized patients with COVID-19 confirmed by troponin I measurement.

Material and methods

Case-control study nested in a cohort of patients of a third-level hospital. Descriptive statistics were used to characterize the population. Qualitative variables were expressed as proportions and ranges, quantitative variables as means and standard deviation. Fisher's exact test was used to compare mortality between patients with and without myocardial damage. A p value < 0.05 was considered significant.

Results

From June 2020 to August 2020, 28 patients who met the selection criteria were enrolled, out of which 15 had no myocardial damage and 13 had myocardial damage assessed by serum troponin measurement. A strong association was found between mortality and the presence of myocardial damage, since mortality was 20% (3/15) among patients without myocardial damage and 92.3% (12/13) among those with myocardial damage (Fisher's exact test, p < 0.005).

Conclusion

Mortality in patients with COVID-19 is associated with myocardial damage assessed by troponin I measurement.

Mitochondrial Dysfunction in Cardiac Diseases and Therapeutic Strategies

Mitochondria are the main site of intracellular synthesis of ATP, which provides energy for various physiological activities of the cell. Cardiomyocytes have a high density of mitochondria and mitochondrial damage is present in a variety of cardiovascular diseases. In this paper, we describe mitochondrial damage in mitochondrial cardiomyopathy, congenital heart disease, coronary heart disease, myocardial ischemia-reperfusion injury, heart failure, and drug-induced cardiotoxicity, in the context of the key roles of mitochondria in cardiac development and homeostasis. Finally, we discuss the main current therapeutic strategies aimed at alleviating mitochondrial impairment-related cardiac dysfunction, including pharmacological strategies, gene therapy, mitochondrial replacement therapy, and mitochondrial transplantation. It is hoped that this will provide new ideas for the treatment of cardiovascular diseases.

Cardiovascular Safety of Hydroxychloroquine-Azithromycin in 424 COVID-19 Patients

Background and Objectives: Hydroxychloroquine (HCQ) combined with azithromycin (AZM) has been widely administered to patients with COVID-19 despite scientific controversies. In particular, the potential of prolong cardiac repolarization when using this combination has been discussed. Materials and Methods: We report a pragmatic and simple safety approach which we implemented among the first patients treated for COVID-19 in our center in early 2020. Treatment contraindications were the presence of severe structural or electrical heart disease, baseline corrected QT interval (QTc) > 500 ms, hypokalemia, or other drugs prolonging QTc that could not be interrupted. Electrocardiogram and QTc was evaluated at admission and re-evaluated after 48 h of the initial prescription. Results: Among the 424 consecutive adult patients (mean age 46.3 ± 16.1 years; 216 women), 21.5% patients were followed in conventional wards and 78.5% in a day-care unit. A total of 11 patients (2.6%) had contraindications to the HCQ-AZ combination. In the remaining 413 treated patients, there were no arrhythmic events in any patient during the 10-day treatment regimen. QTc was slightly but statistically significantly prolonged by 3.75 ± 25.4 ms after 2 days of treatment (p = 0.003). QTc prolongation was particularly observed in female outpatients <65 years old without cardiovascular disease. Ten patients (2.4%) developed QTc prolongation > 60 ms, and none had QTc > 500 ms. Conclusions: This report does not aim to contribute to knowledge of the efficacy of treating COVID-19 with HCQ-AZ. However, it shows that a simple initial assessment of patient medical history, electrocardiogram (ECG), and kalemia identifies contraindicated patients and enables the safe treatment of COVID-19 patients with HCQ-AZ. QT-prolonging anti-infective drugs can be used safely in acute life-threatening infections, provided that a strict protocol and close collaboration between infectious disease specialists and rhythmologists are applied.

Anti-malarial drugs: Mechanisms underlying their proarrhythmic effects

Malaria remains the leading cause of parasitic death in the world. Artemisinin resistance is an emerging threat indicating an imminent need for novel combination therapy. Given the key role of mass drug administration, it is pivotal that the safety of anti-malarial drugs is investigated thoroughly prior to widespread use. Cardiotoxicity, most prominently arrhythmic risk, has been a concern for anti-malarial drugs. We clarify the likely underlying mechanisms by which anti-malarial drugs predispose to arrhythmias. These relate to disruption of (1) action potential upstroke due to effects on the sodium currents, (2) action potential repolarisation due to effects on the potassium currents, (3) cellular calcium homeostasis, (4) mitochondrial function and reactive oxygen species production and (5) cardiac fibrosis. Together, these alterations promote arrhythmic triggers and substrates. Understanding these mechanisms is essential to assess the safety of these drugs, stratify patients based on arrhythmic risk and guide future anti-malarial drug development.

Review of Hydroxychloroquine Cardiotoxicity: Lessons From the COVID-19 Pandemic

Purpose of Review

The coronavirus disease 2019 (COVID-19) pandemic has popularized the usage of hydroxychloroquine and chloroquine (HCQ/CQ) as treatments for COVID-19. Previously used as anti-malarial and now commonly used in rheumatologic conditions, preliminary in vitro studies have demonstrated these medications also have anti-viral properties. Retinopathy and neuromyopathy are well recognized complications of using these treatments; however, cardiotoxicity is under-recognized. This review will discuss the implications and cardiotoxicity of HCQ/CQ, their mechanisms of action, and their utility in COVID-19.

Recent Findings

Early clinical trials demonstrated a modest benefit of HCQ in COVID-19, causing a push for the usage of it. However, further large multi-center randomized control centers, demonstrated no benefit, and even a trend towards worse outcomes. The predominant cardiac complication observed with HCQ in COVID-19 was cardiac arrhythmias and prolonging of the QT interval. However, with chronic usage of HCQ/CQ, the development of heart failure (HF) and cardiomyopathy (CM) can occur.

Summary

Although, most adverse cardiac events related to HCQ/CQ usage in COVID-19 were secondary to conduction disorders given the short duration of treatment, HCQ/CQ can cause CM and HF, with chronic usage. Given the insufficient evidence, HCQ/CQ usage in COVID-19 is not routinely recommended, especially with novel therapies now being developed and used. Additionally, usage of HCQ/CQ should prompt initial cardiac evaluation with ECG, and yearly monitoring, with consideration for advanced imaging if clinically warranted. The diagnosis of HCQ/CQ cardiomyopathy is important, as prompt cessation can allow for recovery when these changes are still reversible.

Cardiovascular Risks of Hydroxychloroquine vs Methotrexate in Patients With Rheumatoid Arthritis

BACKGROUND

Hydroxychloroquine is often used as a first-line treatment of rheumatoid arthritis despite limited evidence on its cardiovascular risk.

OBJECTIVES

We conducted a cardiovascular safety evaluation comparing hydroxychloroquine to methotrexate among patients with rheumatoid arthritis.

METHODS

Using Medicare data (2008-2016), we identified 54,462 propensity score-matched patients with rheumatoid arthritis, aged ≥65 years, who initiated hydroxychloroquine or methotrexate. Primary outcomes were sudden cardiac arrest or ventricular arrythmia (SCA/VA) and major adverse cardiovascular event (MACE). Secondary outcomes were cardiovascular mortality, all-cause mortality, myocardial infarction, stroke, and hospitalized heart failure (HF). We also examined treatment effect modification by history of HF.

RESULTS

Hydroxychloroquine was not associated with risk of SCA/VA (HR: 1.03; 95% CI: 0.79-1.35) or MACE (HR: 1.07; 95% CI: 0.97-1.18) compared with methotrexate. In patients with history of HF, hydroxychloroquine initiators had a higher risk of MACE (HR: 1.30; 95% CI: 1.08-1.56), cardiovascular mortality (HR: 1.34; 95% CI: 1.06-1.70), all-cause mortality (HR: 1.22; 95% CI: 1.04-1.43), myocardial infarction (HR: 1.74; 95% CI: 1.25-2.42), and hospitalized HF (HR: 1.29; 95% CI: 1.07-1.54) compared to methotrexate initiators. Cardiovascular risks were not different in patients without history of HF except for an increased hospitalized HF risk (HR: 1.57; 95% CI: 1.30-1.90) among hydroxychloroquine initiators.

CONCLUSIONS

In older patients with rheumatoid arthritis, hydroxychloroquine and methotrexate showed similar SCA/VA and MACE risks; however, hydroxychloroquine initiators with history of HF had higher risks of MACE, cardiovascular mortality, all-cause mortality, and myocardial infarction. An increased hospitalized HF risk was observed among hydroxychloroquine initiators regardless of an HF history.

Neglected Tropical Diseases and Sudden Cardiac Death: The NET-Heart Project

Sudden cardiac death (SCD) is responsible for approximately 6% of global mortality and 25% of cardiovascular (CV) deaths. SCD has been traditionally linked to coronary artery disease, valvular heart disease, cardiomyopathies, and genetic arrhythmia disorders. However, advancements in care for these diseases have not translated to a proportional reduction in SCD. This suggests an important role of underrecognized contributing pathologies. Neglected tropical diseases (NTDs) are a group of illnesses prevalent in tropical and sub-tropical regions which have been understudied partially due to their high prevalence in marginalized populations. The relationship between SCD and Chagas disease has been well-established, though emerging literature suggests that other NTDs with CV involvement may lead to fatal arrhythmias. Additionally, specific therapies for a subset of NTDs put patients at increased risk of malignant arrhythmias and other cardiac complications. This review aims to summarize the association between a group of selected NTDs and SCD.

Early Alterations of QTc in Patients with COVID-19 Treated with Hydroxychloroquine or Chloroquine in Libreville, Gabon

The objective of this study was to analyze the effect of hydroxychloroquine or chloroquine associated with azithromycin on the QTc interval in Gabonese patients treated for COVID-19.

METHODS

This was an observational study conducted from April to June 2020, at the Libreville University Hospital Center in Gabon. Patients admitted for COVID-19 and treated with hydroxychloroquine or chloroquine, each combined with azithromycin were included. The QTc interval was measured upon admission and 48 h after starting treatment. The primary endpoint was QTc prolongation exceeding 60 ms and/or a QTc value exceeding 500 ms at 48 h.

RESULTS

Data from 224 patients, 102 (45.5%) who received hydroxychloroquine and 122 treated with chloroquine, were analyzed. The median baseline QTc was 396 (369-419) ms. After 48 h of treatment, 50 (22.3%) patients had a significant prolongation of QTc. This tended to be more frequent in patients treated with chloroquine (n = 33; 27.0%) than in those treated with hydroxychloroquine (n = 17; 16.7%) (p = 0.06). QTc prolongation exceeding 60 ms was found in 48 (21.3%) patients, while 11 patients had a (4.9%) QTc exceeding 60 ms at admission and exceeding 500 ms after 48 h.

CONCLUSION

Early QTc prolongation is frequent in COVID-19 patients treated with hydroxychloroquine or chloroquine in association with azithromycin.

Effect of hydroxychloroquine on the cardiac ventricular repolarization: A randomized clinical trial

AIMS

Hydroxychloroquine has been suggested as possible treatment for severe acute respiratory syndrome-coronavirus-2. Studies reported an increased risk of QTcF-prolongation after treatment with hydroxychloroquine. The aim of this study was to analyse the concentration-dependent effects of hydroxychloroquine on the ventricular repolarization, including QTcF-duration and T-wave morphology.

METHODS

Twenty young (≤30 y) and 20 elderly (65-75 y) healthy male subjects were included. Subjects were randomized to receive either a total dose of 2400 mg hydroxychloroquine over 5 days, or placebo (ratio 1:1). Follow-up duration was 28 days. Electrocardiograms (ECGs) were recorded as triplicate at baseline and 4 postdose single recordings, followed by hydroxychloroquine concentration measurements. ECG intervals (RR, QRS, PR, QTcF, J-Tpc, Tp-Te) and T-wave morphology, measured with the morphology combination score, were analysed with a prespecified linear mixed effects concentration-effect model.

RESULTS

There were no significant associations between hydroxychloroquine concentrations and ECG characteristics, including RR-, QRS- and QTcF-interval (P = .09, .34, .25). Mean ΔΔQTcF-interval prolongation did not exceed 5 ms and the upper limit of the 90% confidence interval did not exceed 10 ms at the highest measured concentrations (200 ng/mL). There were no associations between hydroxychloroquine concentration and the T-wave morphology (P = .34 for morphology combination score). There was no significant effect of age group on ECG characteristics.

CONCLUSION

In this study, hydroxychloroquine did not affect ventricular repolarization, including the QTcF-interval and T-wave morphology, at plasma concentrations up to 200 ng/mL. Based on this analysis, hydroxychloroquine does not appear to increase the risk of QTcF-induced arrhythmias.

Evidence for the early emergence of piperaquine-resistant Plasmodium falciparum malaria and modeling strategies to mitigate resistance

Multidrug-resistant Plasmodium falciparum parasites have emerged in Cambodia and neighboring countries in Southeast Asia, compromising the efficacy of first-line antimalarial combinations. Dihydroartemisinin + piperaquine (PPQ) treatment failure rates have risen to as high as 50% in some areas in this region. For PPQ, resistance is driven primarily by a series of mutant alleles of the P. falciparum chloroquine resistance transporter (PfCRT). PPQ resistance was reported in China three decades earlier, but the molecular driver remained unknown. Herein, we identify a PPQ-resistant pfcrt allele (China C) from Yunnan Province, China, whose genotypic lineage is distinct from the PPQ-resistant pfcrt alleles currently observed in Cambodia. Combining gene editing and competitive growth assays, we report that PfCRT China C confers moderate PPQ resistance while re-sensitizing parasites to chloroquine (CQ) and incurring a fitness cost that manifests as a reduced rate of parasite growth. PPQ transport assays using purified PfCRT isoforms, combined with molecular dynamics simulations, highlight differences in drug transport kinetics and in this transporter’s central cavity conformation between China C and the current Southeast Asian PPQ-resistant isoforms. We also report a novel computational model that incorporates empirically determined fitness landscapes at varying drug concentrations, combined with antimalarial susceptibility profiles, mutation rates, and drug pharmacokinetics. Our simulations with PPQ-resistant or -sensitive parasite lines predict that a three-day regimen of PPQ combined with CQ can effectively clear infections and prevent the evolution of PfCRT variants. This work suggests that including CQ in combination therapies could be effective in suppressing the evolution of PfCRT-mediated multidrug resistance in regions where PPQ has lost efficacy.

The recent emergence of Plasmodium falciparum parasite resistance to the antimalarial drug piperaquine (PPQ) has contributed to frequent treatment failures across Southeast Asia, originating in Cambodia. Here, we show that earlier reports of PPQ resistance in Yunnan Province, China could be explained by the unique China C variant of the P. falciparum chloroquine resistance transporter PfCRT. Gene-edited parasites show a loss of fitness and parasite resensitization to the chemically related former first-line antimalarial chloroquine, while acquiring PPQ resistance via drug efflux. Molecular features of drug resistance were examined using biochemical assays to measure mutant PfCRT-mediated drug transport and molecular dynamics simulations with the recently solved PfCRT structure to assess changes in the central drug-binding cavity. We also describe a new computational model that incorporates parasite mutation rates, fitness costs, antimalarial susceptibilities, and drug pharmacological profiles to predict how infections with parasite strains expressing distinct PfCRT variants can evolve and be selected in response to different drug pressures and regimens. Simulations predict that a three-day regimen of PPQ plus chloroquine would be fully effective at preventing recrudescence of drug-resistant infections.

Strengthening therapeutic adherence and pharmacovigilance to antimalarial treatment in Manaus, Brazil: a multicomponent strategy using mHealth

BACKGROUND

Public health initiatives for improving adherence to primaquine based regimens and enhancing effective pharmacovigilance are needed to support the efforts for malaria elimination in real world conditions.

METHODS

A multicomponent patient-oriented strategy using a Smart Safety Surveillance (3S) approach including: (1) educational materials for treatment counselling and identification of warning symptoms of haemolytic anaemia; (2) an mHealth component using Short Message Service (SMS) treatment reminders and (3) development and implementation of follow-up phone surveys three days after treatment completion, using a web-based platform linked to the local information system of malaria. Adherence was measured using the Morisky Medication Adherence Scale. Self-reported events were registered using a structured questionnaire and communicated to the Brazilian Health Regulatory Agency.

RESULTS

Educational materials were disseminated to 5594 patients, of whom 1512 voluntarily entered the mHealth component through the local information system; 7323 SMS were sent, and 1062 participants completed a follow-up survey after treatment. The mean age of patients was 37.36 years (SD 13.65), 61.24% were male, 98.54% were infected with. Plasmodium vivax and 95.90% received a short regimen of chloroquine plus primaquine (CQ + PQ 7 days), as per malaria case management guidelines in Brazil. From the 1062 surveyed participants 93.31% were considered adherent to the treatment. Most of the patients (95.20%) reported at least one adverse event. Headache, lack of appetite and nausea/vomiting were the most frequently reported adverse events by 77.31%, 70.90% and 56.78% of the patients respectively. A quarter of the patients reported anxiety or depression symptoms; 57 (5.37%) patients reported 5 to 6 warning symptoms of haemolytic anaemia including jaundice and dark urine in 44 (4.14%). Overall, three patients presenting symptoms of haemolytic anaemia attended a hospital and were diagnosed with G6PD deficiency, and one had haemolysis. All of them recovered.

CONCLUSIONS

Under real world conditions, a multicomponent patient-oriented strategy using information and communication technologies allowed health care providers to reinforce treatment adherence and enhance safety surveillance of adverse events associated with regimens using primaquine. Active monitoring through phone surveys also reduced under-reporting of ADRs. This approach is low-cost, scalable and able to support prioritized activities of the national malaria programme.

Myth surrounding the FDA disapproval of hydroxychloroquine sulfate and chloroquine phosphate as drugs for coronavirus disease 2019

Chloroquine (CQ) and its analog hydroxychloroquine (HCQ) are popular antimalarial drugs that also exhibit wide range of activities against other diseases such as cancer, diabetes, HIV, and microbial infections, among others. They are also reported to possess antioxidant properties. The popularity of these drugs skyrocketed with the emergence of coronavirus disease 2019 (COVID-19) that has caused the deaths of over 600,000,000 people worldwide just within 7 months. Due to the urgency of the time in discovering or repurposing new drugs that will be active against SARS-CoV-2, the causative agent of COVID-19, some initial in vitro studies found prospects in CQ and HCQ against SARS-CoV-2. HCQ instantly became a drug of choice over CQ for the treatment of COVID-19 patients because it is readily absorbed and less toxic. However, clinical studies found no positive indices to support the continued use of HCQ. This chapter looks into this by consulting current literatures in order to unravel the myth surrounding the approval and disapproval of the use of HCQ.

Telemedicine and Teleconsulting in the Era of COVID-19 Pandemic: A Useful Tool from Screening to Intensive Care Monitoring

The COVID-19 global pandemic has had striking effects on clinical practice and medical assistance and the progressive evolution of telemedicine and telehealth systems has allowed healthcare professionals to connect with patients yet respecting the striking need for social distancing. This article aims to review the possible ways to use telehealth and teleconsulting systems to guarantee an adequate level of clinical assistance starting from screening procedures up to support the management of patients admitted to intensive care units area, thus balancing the need to ensure continuity of care and at the same time limiting the possible sources of contagion expansion. Telemedicine may be a useful tool to improve clinical assistance and reduce the financial burden on the health system in a long-term view. Although it cannot completely replace patient-physician interactions, it would be desirable to implement this field and made it accessible to the largest part of the population.

Curcumin modulates multiple cell death, matrix metalloproteinase activation and cardiac protein release in susceptible and resistant Plasmodium berghei-infected mice

Pro-inflammatory signaling, cell death, and metalloproteinases activation are events in Plasmodium infection. However, it is not known if treatment with mefloquine (MF), and curcumin (CM) supplementation, will modulate these conditions. Malaria was induced in two different studies using susceptible (NK 65, study 1) and resistant (ANKA, study 2) strains of mouse malaria parasites (Plasmodium berghei) in thirty male Swiss mice (n = 5) in each study. Following confirmation of parasitemia, mice received 10 mL/kg distilled water (infected control), MF (10 mg/kg), MF and CM (25 mg/kg), MF and CM (50 mg/kg), CM (25 mg/kg) and CM (50 mg/kg). Five mice (not infected) were used as control. After treatment, the animals were sacrificed, serum obtained and liver mitochondria were isolated. Serum Tumour Necrosis Factor alpha (TNF-α), C-reactive protein (CRP), Interleukins-1 beta (IL-1β) and Interleukins-6 (IL-6) as well as caspases-3, 9 (C3 and C9), p53, serum troponin I (TI) and creatine kinase (CK), were assayed using ELISA techniques. Mitochondrial membrane permeability transition (mPT) pore opening, mitochondrial F₀F₁ ATPase activity, and lipid peroxidation (mLPO) were determined spectrophotometrically. Matrix metalloproteinases 2 (MMP-2) and 9 (MMP-9) expressions were determined using electrophoresis. CM supplementation (25 mg/kg) significantly decreased serum p53, TNF-α, CRP and IL-6 compared with MF. In the resistant model, CM prevented mPT pore opening, significantly decreased F₀F₁ ATPase activity and mLPO. MF activated caspase-3 while supplementation with CM significantly decreased this effect. Furthermore, MMP-2 and MMP-9 were selectively expressed in the susceptible model. Malarial treatment with mefloquine elicits different cell death responses while supplementation with curcumin decreased TI level and CK activities.

Electrophysiological and Proarrhythmic Effects of Hydroxychloroquine Challenge in Guinea-Pig Hearts

Hydroxychloroquine (HCQ), clinically established in antimalarial and autoimmune therapy, recently raised cardiac arrhythmogenic concerns when used alone or with azithromycin (HCQ+AZM) in Covid-19. We report complementary, experimental, studies of its electrophysiological effects. In patch clamped HEK293 cells expressing human cardiac ion channels, HCQ inhibited IKr and IK1 at a therapeutic concentrations (IC50s: 10 ± 0.6 and 34 ± 5.0 μM). INa and ICaL showed higher IC50s; Ito and IKs were unaffected. AZM slightly inhibited INa, ICaL, IKs, and IKr, sparing IK1 and Ito. (HCQ+AZM) inhibited IKr and IK1 (IC50s: 7.7 ± 0.8 and 30.4 ± 3.0 μM), sparing INa, ICaL, and Ito. Molecular induced-fit docking modeling confirmed potential HCQ-hERG but weak AZM-hERG binding. Effects of μM-HCQ were studied in isolated perfused guinea-pig hearts by multielectrode, optical RH237 voltage, and Rhod-2 mapping. These revealed reversibly reduced left atrial and ventricular action potential (AP) conduction velocities increasing their heterogeneities, increased AP durations (APDs), and increased durations and dispersions of intracellular [Ca2+] transients, respectively. Hearts also became bradycardic with increased electrocardiographic PR and QRS durations. The (HCQ+AZM) combination accentuated these effects. Contrastingly, (HCQ+AZM) and not HCQ alone disrupted AP propagation, inducing alternans and torsadogenic-like episodes on voltage mapping during forced pacing. O'Hara-Rudy modeling showed that the observed IKr and IK1 effects explained the APD alterations and the consequently prolonged Ca2+ transients. The latter might then downregulate INa, reducing AP conduction velocity through recently reported INa downregulation by cytosolic [Ca2+] in a novel scheme for drug action. The findings may thus prompt future investigations of HCQ's cardiac safety under particular, chronic and acute, clinical situations.

Regioselective Functionalization of Quinolines through C-H Activation: A Comprehensive Review

Quinoline is a versatile heterocycle that is part of numerous natural products and countless drugs. During the last decades, this scaffold also became widely used as ligand in organometallic catalysis. Therefore, access to functionalized quinolines is of great importance and continuous efforts have been made to develop efficient and regioselective synthetic methods. In this regard, C-H functionalization through transition metal catalysis, which is nowadays the Graal of organic green chemistry, represents the most attractive strategy. We aim herein at providing a comprehensive review of methods that allow site-selective metal-catalyzed C-H functionalization of quinolines, or their quinoline N-oxides counterparts, with a specific focus on their scope and limitations, as well as mechanistic aspects if that accounts for the selectivity.

The cardiovascular effects of amodiaquine and structurally related antimalarials: An individual patient data meta-analysis

BACKGROUND

Amodiaquine is a 4-aminoquinoline antimalarial similar to chloroquine that is used extensively for the treatment and prevention of malaria. Data on the cardiovascular effects of amodiaquine are scarce, although transient effects on cardiac electrophysiology (electrocardiographic QT interval prolongation and sinus bradycardia) have been observed. We conducted an individual patient data meta-analysis to characterise the cardiovascular effects of amodiaquine and thereby support development of risk minimisation measures to improve the safety of this important antimalarial.

METHODS AND FINDINGS

Studies of amodiaquine for the treatment or prevention of malaria were identified from a systematic review. Heart rates and QT intervals with study-specific heart rate correction (QTcS) were compared within studies and individual patient data pooled for multivariable linear mixed effects regression. The meta-analysis included 2,681 patients from 4 randomised controlled trials evaluating artemisinin-based combination therapies (ACTs) containing amodiaquine (n = 725), lumefantrine (n = 499), piperaquine (n = 716), and pyronaridine (n = 566), as well as monotherapy with chloroquine (n = 175) for uncomplicated malaria. Amodiaquine prolonged QTcS (mean = 16.9 ms, 95% CI: 15.0 to 18.8) less than chloroquine (21.9 ms, 18.3 to 25.6, p = 0.0069) and piperaquine (19.2 ms, 15.8 to 20.5, p = 0.0495), but more than lumefantrine (5.6 ms, 2.9 to 8.2, p < 0.001) and pyronaridine (-1.2 ms, -3.6 to +1.3, p < 0.001). In individuals aged ≥12 years, amodiaquine reduced heart rate (mean reduction = 15.2 beats per minute [bpm], 95% CI: 13.4 to 17.0) more than piperaquine (10.5 bpm, 7.7 to 13.3, p = 0.0013), lumefantrine (9.3 bpm, 6.4 to 12.2, p < 0.001), pyronaridine (6.6 bpm, 4.0 to 9.3, p < 0.001), and chloroquine (5.9 bpm, 3.2 to 8.5, p < 0.001) and was associated with a higher risk of potentially symptomatic sinus bradycardia (≤50 bpm) than lumefantrine (risk difference: 14.8%, 95% CI: 5.4 to 24.3, p = 0.0021) and chloroquine (risk difference: 8.0%, 95% CI: 4.0 to 12.0, p < 0.001). The effect of amodiaquine on the heart rate of children aged <12 years compared with other antimalarials was not clinically significant. Study limitations include the unavailability of individual patient-level adverse event data for most included participants, but no serious complications were documented.

CONCLUSIONS

While caution is advised in the use of amodiaquine in patients aged ≥12 years with concomitant use of heart rate-reducing medications, serious cardiac conduction disorders, or risk factors for torsade de pointes, there have been no serious cardiovascular events reported after amodiaquine in widespread use over 7 decades. Amodiaquine and structurally related antimalarials in the World Health Organization (WHO)-recommended dose regimens alone or in ACTs are safe for the treatment and prevention of malaria.

Study protocol: an open-label individually randomised controlled trial to assess the efficacy of artemether-lumefantrine prophylaxis for malaria among forest goers in Cambodia

INTRODUCTION

In the Greater Mekong Subregion, adults are at highest risk for malaria. The most relevant disease vectors bite during daytime and outdoors which makes forest work a high-risk activity for malaria. The absence of effective vector control strategies and limited periods of exposure during forest visits suggest that chemoprophylaxis could be an appropriate strategy to protect forest goers against malaria.

METHODS AND ANALYSIS

The protocol describes an open-label randomised controlled trial of artemether-lumefantrine (AL) versus multivitamin as prophylaxis against malaria among forest goers aged 16-65 years in rural northeast Cambodia. The primary objective is to compare the efficacy of the artemisinin combination therapy AL versus a multivitamin preparation as defined by the 28-day PCR parasite positivity rate and incidence of confirmed clinical malaria of any species. The sample size is 2200 patient-episodes of duration 1 month in each arm. The duration of follow-up and prophylaxis for each participant is 1, 2 or 3 consecutive 28-day periods, followed by a further 28 days of post-exposure prophylaxis, depending on whether they continue to visit the forest. Analysis will be done both by intention to treat and per protocol.

ETHICS AND DISSEMINATION

All participants will provide written, informed consent. Ethical approval was obtained from the Oxford Tropical Research Ethics Committee and the Cambodia National Ethics Committee for Health Research. Results will be disseminated by peer-reviewed open access publication together with open data.

TRIAL REGISTRATION NUMBER

NCT04041973; Pre-result.

Adverse Effects Associated With the Use of Antimalarials During The COVID-19 Pandemic in a Tertiary Care Center in Mexico City

Background: Antimalarial drugs were widely used as experimental therapies against COVID-19 in the initial stages of the pandemic. Despite multiple randomized controlled trials demonstrating unfavorable outcomes in both efficacy and adverse effects, antimalarial drugs are still prescribed in developing countries, especially in those experiencing recurrent COVID-19 crises (India and Brazil). Therefore, real-life experience and pharmacovigilance studies describing the use and side effects of antimalarials for COVID-19 in developing countries are still relevant.

Objective: To describe the adverse effects associated with the use of antimalarial drugs in hospitalized patients with COVID-19 pneumonia at a reference center in Mexico City.

Methods: We integrated a retrospective cohort with all adult patients hospitalized for COVID-19 pneumonia from March 13th, 2020, to May 17th, 2020. We compared the baseline characteristics (demographic and clinical) and the adverse effects between the groups of patients treated with and without antimalarial drugs. The mortality analysis was performed in 491 patients who received optimal care and were not transferred to other institutions (210 from the antimalarial group and 281 from the other group).

Results: We included 626 patients from whom 38% (n = 235) received an antimalarial drug. The mean age was 51.2 ± 13.6 years, and 64% were males. At baseline, compared with the group treated with antimalarials, the group that did not receive antimalarials had more dyspnea (82 vs. 73%, p = 0.017) and cyanosis (5.3 vs. 0.9%, p = 0.009), higher respiratory rate (median of 28 vs. 24 bpm, p < 0.001), and lower oxygen saturation (median of 83 vs. 87%, p < 0.001). In the group treated with antimalarials, 120 patients had two EKG evaluations, from whom 12% (n = 16) prolonged their QTc from baseline in more than 50 ms, and six developed a ventricular arrhythmia. Regarding the trajectories of the liver function tests over time, no significant differences were found for the change in the mean value per day between the two groups. Among patients who received optimal care, the mortality was 16% (33/210) in those treated with antimalarials and 15% (41/281) in those not receiving antimalarials (RR 1.08, 95% 0.75–1.64, and adjusted RR 1.12, 95% CI 0.69–1.82).

Conclusion: The adverse events in patients with COVID-19 treated with antimalarials were similar to those who did not receive antimalarials at institutions with rigorous pharmacological surveillance. However, they do not improve survival in patients who receive optimal medical care.

Effect of Hydroxychloroquine on QTc in Patients Diagnosed with COVID-19: A Systematic Review and Meta-Analysis

BACKGROUND

Hydroxychloroquine or chloroquine with or without the concomitant use of azithromycin have been widely used to treat patients with SARS-CoV-2 infection, based on early in vitro studies, despite their potential to prolong the QTc interval of patients.

OBJECTIVE

This is a systematic review and metanalysis designed to assess the effect of hydroxychloroquine with or without the addition of azithromycin on the QTc of hospitalized patients with COVID-19.

MATERIALS AND METHODS

PubMed, Scopus, Cochrane and MedRxiv databases were reviewed. A random effect model meta-analysis was used, and I-square was used to assess the heterogeneity. The prespecified endpoints were ΔQTc, QTc prolongation > 500 ms and ΔQTc > 60 ms.

RESULTS

A total of 18 studies and 7179 patients met the inclusion criteria and were included in this systematic review and meta-analysis. The use of hydroxychloroquine with or without the addition of azithromycin was associated with increased QTc when used as part of the management of patients with SARS-CoV-2 infection. The combination therapy with hydroxychloroquine plus azithromycin was also associated with statistically significant increases in QTc. Moreover, the use of hydroxychloroquine alone, azithromycin alone, or the combination of the two was associated with increased numbers of patients that developed QTc prolongation > 500 ms.

CONCLUSION

This systematic review and metanalysis revealed that the use of hydroxychloroquine alone or in conjunction with azithromycin was linked to an increase in the QTc interval of hospitalized patients with SARS-CoV-2 infection that received these agents.

Torsade de pointes associated with chloroquine, hydroxychloroquine, and azithromycin: a retrospective analysis of individual case safety reports from VigiBase

PURPOSE

To analyze the cases of torsade de pointes (TdP) and related symptoms reported in association with chloroquine (CQ), hydroxychloroquine (HCQ), and azithromycin (AZT) to the World Health Organization (WHO) global database of individual case safety reports (ICSRs) for drug monitoring (VigiBase) using qualitative and quantitative pharmacovigilance approaches.

METHODS

The main characteristics of the ICSRs reporting TdP with CQ, HCQ, and AZT have been summarized. Co-reported drugs with risk to cause QT prolongation have been described. Reporting odds ratios (RORs) as a measure of disproportionality for reported TdP and individual drugs have been calculated.

RESULTS

One hundred seventy ICSRs reporting TdP in association with the drugs of interest were identified (CQ: 11, HCQ: 31, CQ + HCQ: 1, HCQ + AZT: 27, AZT: 100). From these, 41 (24.3%) were received during the pandemic period (December 2019 to February 2021). The median age of the patients was 63, 53, and 63 years old for CQ, HCQ, and AZT, respectively. Reports included concomitant use of other QT-prolonging drugs (CQ 25.0%, HCQ 71.2%, AZT 64.6%). A proportion of the cases were fatal (CQ 25.0%, HCQ 8.6%, AZT 16.1%). Increased disproportionality has been found for the individual drugs and TdP: CQ (ROR: 7.41, 95% confidence interval (CI): 3.82, 12.96), HCQ (ROR: 8.49, 95% CI: 6.57, 10.98), azithromycin (ROR: 8.06, 95% CI: 6.76, 9.61). Disproportionality was also found for other related symptoms, Standardized MedDRA Query for torsade de pointes/QT prolongation (narrow): CQ (ROR: 11.95, 95% CI: 10.04-14.22); HCQ (ROR: 20.43, 95% CI: 19.13, 21.83), AZT (ROR: 7.78, 95% CI: 7.26, 8.34).

CONCLUSIONS

The prescription of CQ, HCQ, and AZT should be restricted to therapeutic indications with established positive benefit/risk profile. Doctors and patients should be aware of this potential adverse reaction especially when several risk factors are present.

Hydroxychloroquine Inhibits Cardiac Conduction in Aged Patients with Nonmalaria Diseases

Background

The COVID-19 pandemic has brought increased focus on hydroxychloroquine (HCQ), as doctors, the medical community, and policymakers around the world attempt to understand how the risks of HCQ weigh against unknown benefits. We aim to evaluate the effects of HCQ on cardiac conduction, thus contributing to the global understanding of implications of HCQ use.

Methods

We reviewed 717 cases of nonmalaria patients treated with HCQ (302) or without HCQ (415) in our hospital from 2008 to 2019, analyzed the cardiac conduction recorded by electrocardiogram (122 vs. 180) including heart rate (HR), PR, and corrected-QT (QTc) intervals, and explored the relationship of cardiac conduction with age, HCQ dosage, HCQ duration, sex, and primary diseases in HCQ users.

Results

The all-cause mortality is similar between HCQ and non-HCQ groups (4.0 vs. 4.3%, p = 0.85). Patients aged 45 years or older, not younger ones, have lower HR (80.1 ± 1.7 vs. 85.7 ± 1.8 bpm, p = 0.03) but longer PR (163 ± 3.4 vs. 146.6 ± 4.2 ms, p = 0.003) and QTc (417.8 ± 3.8 vs. 407.7 ± 2.7 ms, p = 0.03) in HCQ than those in non-HCQ. The age in the HCQ group is positively correlated with PR (R = 0.31, p < 0.01) and QTc (R = 0.34, p < 0.01) but not HR. HR, PR, and QTc are not related to HCQ dosage (0.1–0.6 g/day), HCQ duration (0.2–126 months), sex, primary diseases, and repeated exams.

Conclusion

Age is the most important risk factor of HCQ on cardiac conduction in nonmalaria patients. Electrocardiogram monitoring is suggested in aged patients due to the effects of HCQ on HR, PR, and QTc.

Cardiac TdP risk stratification modelling of anti-infective compounds including chloroquine and hydroxychloroquine

Hydroxychloroquine (HCQ), the hydroxyl derivative of chloroquine (CQ), is widely used in the treatment of rheumatological conditions (systemic lupus erythematosus, rheumatoid arthritis) and is being studied for the treatment and prevention of COVID-19. Here, we investigate through mathematical modelling the safety profile of HCQ, CQ and other QT-prolonging anti-infective agents to determine their risk categories for Torsade de Pointes (TdP) arrhythmia. We performed safety modelling with uncertainty quantification using a risk classifier based on the qNet torsade metric score, a measure of the net charge carried by major currents during the action potential under inhibition of multiple ion channels by a compound. Modelling results for HCQ at a maximum free therapeutic plasma concentration (free C max) of approximately 1.2 µM (malaria dosing) indicated it is most likely to be in the high-intermediate-risk category for TdP, whereas CQ at a free C max of approximately 0.7 µM was predicted to most likely lie in the intermediate-risk category. Combining HCQ with the antibacterial moxifloxacin or the anti-malarial halofantrine (HAL) increased the degree of human ventricular action potential duration prolongation at some or all concentrations investigated, and was predicted to increase risk compared to HCQ alone. The combination of HCQ/HAL was predicted to be the riskiest for the free C max values investigated, whereas azithromycin administered individually was predicted to pose the lowest risk. Our simulation approach highlights that the torsadogenic potentials of HCQ, CQ and other QT-prolonging anti-infectives used in COVID-19 prevention and treatment increase with concentration and in combination with other QT-prolonging drugs.

Cardiotoxic Potential of Hydroxychloroquine, Chloroquine and Azithromycin in Adult Human Primary Cardiomyocytes

Substantial efforts have been recently committed to develop coronavirus disease-2019 (COVID-19) medications, and Hydroxychloroquine alone or in combination with Azithromycin has been promoted as a repurposed treatment. Although these drugs may increase cardiac toxicity risk, cardiomyocyte mechanisms underlying this risk remain poorly understood in humans. Therefore, we evaluated the proarrhythmia risk and inotropic effects of these drugs in the cardiomyocyte contractility-based model of the human heart. We found Hydroxychloroquine to have a low proarrhythmia risk, whereas Chloroquine and Azithromycin were associated with high risk. Hydroxychloroquine proarrhythmia risk changed to high with low level of K+, whereas high level of Mg2+ protected against proarrhythmic effect of high Hydroxychloroquine concentrations. Moreover, therapeutic concentration of Hydroxychloroquine caused no enhancement of elevated temperature-induced proarrhythmia. Polytherapy of Hydroxychloroquine plus Azithromycin and sequential application of these drugs were also found to influence proarrhythmia risk categorization. Hydroxychloroquine proarrhythmia risk changed to high when combined with Azithromycin at therapeutic concentration. However, Hydroxychloroquine at therapeutic concentration impacted the cardiac safety profile of Azithromycin and its proarrhythmia risk only at concentrations above therapeutic level. We also report that Hydroxychloroquine and Chloroquine, but not Azithromycin, decreased contractility while exhibiting multi-ion channel block features, and Hydroxychloroquine's contractility effect was abolished by Azithromycin. Thus, this study has the potential to inform clinical studies evaluating repurposed therapies, including those in the COVID-19 context. Additionally, it demonstrates the translational value of the human cardiomyocyte contractility-based model as a key early discovery path to inform decisions on novel therapies for COVID-19, malaria, and inflammatory diseases.

Randomized Controlled Trial of the Electrocardiographic Effects of Four Antimalarials for Pregnant Women with Uncomplicated Malaria on the Thailand-Myanmar Border

Quinoline antimalarials cause drug-induced electrocardiograph QT prolongation, a potential risk factor for torsade de pointes. The effects of currently used antimalarials on the electrocardiogram (ECG) were assessed in pregnant women with malaria.

Quinoline antimalarials cause drug-induced electrocardiographic QT prolongation, a potential risk factor for torsade de pointes. The effects of currently used antimalarials on the electrocardiogram (ECG) were assessed in pregnant women with malaria. Pregnant women with microscopy-confirmed parasitemia of any malaria species were enrolled in an open-label randomized controlled trial on the Thailand-Myanmar border from 2010 to 2016. Patients were randomized to the standard regimen of dihydroartemisinin-piperaquine (DP) or artesunate-mefloquine (ASMQ) or an extended regimen of artemether-lumefantrine (AL+). Recurrent Plasmodium vivax infections were treated with chloroquine. Standard 12-lead electrocardiograms were assessed on day 0, 4 to 6 h following the last dose, and day 7. QT was corrected for the heart rate by a linear mixed-effects model-derived population-based correction formula (QTcP = QT/RR^0.381). A total of 86 AL+, 82 ASMQ, 88 DP, and 21 chloroquine-treated episodes were included. No patients had an uncorrected QT interval nor QTcP of >480 ms at any time. QTcP corresponding to peak drug concentration was longer in the DP group (adjusted predicted mean difference, 17.84 ms; 95% confidence interval [CI], 11.58 to 24.10; P < 0.001) and chloroquine group (18.31 ms; 95% CI, 8.78 to 27.84; P < 0.001) than in the AL+ group, but not different in the ASMQ group (2.45 ms; 95% CI, −4.20 to 9.10; P = 0.47) by the multivariable linear mixed-effects model. There was no difference between DP and chloroquine (P = 0.91). QTc prolongation resulted mainly from widening of the JT interval. In pregnant women, none of the antimalarial drug treatments exceeded conventional thresholds for an increased risk of torsade de pointes.

QSAR Modeling for Multi-Target Drug Discovery: Designing Simultaneous Inhibitors of Proteins in Diverse Pathogenic Parasites

Parasitic diseases remain as unresolved health issues worldwide. While for some parasites the treatments involve drug combinations with serious side effects, for others, chemical therapies are inefficient due to the emergence of drug resistance. This urges the search for novel antiparasitic agents able to act through multiple mechanisms of action. Here, we report the first multi-target model based on quantitative structure-activity relationships and a multilayer perceptron neural network (mt-QSAR-MLP) to virtually design and predict versatile inhibitors of proteins involved in the survival and/or infectivity of different pathogenic parasites. The mt-QSAR-MLP model exhibited high accuracy (>80%) in both training and test sets for the classification/prediction of protein inhibitors. Several fragments were directly extracted from the physicochemical and structural interpretations of the molecular descriptors in the mt-QSAR-MLP model. Such interpretations enabled the generation of four molecules that were predicted as multi-target inhibitors against at least three of the five parasitic proteins reported here with two of the molecules being predicted to inhibit all the proteins. Docking calculations converged with the mt-QSAR-MLP model regarding the multi-target profile of the designed molecules. The designed molecules exhibited drug-like properties, complying with Lipinski’s rule of five, as well as Ghose’s filter and Veber’s guidelines.

Malaria and the Heart: JACC State-of-the-Art Review

As one of the tropical diseases, malaria is endemic in developing countries. Severe malaria, mainly caused by the Plasmodium falciparum parasite, can result in life-threatening complications. Traditionally, cardiac involvement has not been included as a frequent cause of morbidity and mortality. This could be due to under-reporting or underdiagnosing. Specific cardiovascular (CV) complications include electrocardiogram abnormalities, myocarditis, pericarditis, pericardial effusion, ischemic disease, and heart failure. According to the data analyzed, CV manifestations can lead to severe consequences. Possible theories related to the pathophysiological mechanisms related to CV compromise include an imbalanced pro-inflammatory cytokine response and/or erythrocyte sequestration by increased cytoadherence to endothelium. Although there is a paucity of data regarding cardiac manifestations of malaria, an algorithm for appropriate use of diagnostic tools to assess cardiac involvement has been developed in this paper. Furthermore, it is important to note that typical antimalarial treatment regimens can have fatal cardiac side-effects.

Botanical candidates from Saudi Arabian flora as potential therapeutics for Plasmodium infection

Malaria is a lethal parasitic disease affecting over two hundred million people worldwide and kills almost half a million people per year. Until now, there is no curative treatment for this disease that has a substantial morbidity. The available chemotherapeutic agents are unable to completely control the infection with the continuous appearance of drug resistance. Consequently, the search for new therapeutic agents with high safety profiles and low side effects is of paramount importance. Several natural products have been investigated and proven to have antimalarial effects either in vivo or in vitro. A large number of plants have been studied globally for their antimalarial activities. However, studies that have been conducted in this field in Saudi Arabia are not enough. This article presents global and local research on the need for novel natural antimalarial agents with a particular emphasis on studies involving plants from Saudi Arabian flora.

COVID-19, hydroxychloroquine and sudden cardiac death: implications for clinical practice in patients with rheumatic diseases

Sudden cardiac death is commonly seen due to arrhythmias, which is a common cardiac manifestation seen in COVID-19 patients, especially those with underlying cardiovascular disease (CVD). Administration of hydroxychloroquine (HCQ) as a potential treatment option during SARS-CoV-2, initially gained popularity, but later, its safe usage became questionable due to its cardiovascular safety, largely stemming from instances of cardiac arrhythmias in COVID-19. Moreover, in the setting of rheumatic diseases, in which patients are usually on HCQ for their primary disease, there is a need to scale the merits and demerits of HCQ usage for the treatment of COVID-19. In this narrative review, we aim to address the association between usage of HCQ and sudden cardiac death in COVID-19 patients. MEDLINE, EMBASE, ClinicalTrials.gov and SCOPUS databases were used to review articles in English ranging from case reports, case series, letter to editors, systematic reviews, narrative reviews, observational studies and randomized control trials. HCQ is a potential cause of sudden cardiac death in COVID-19 patients. As opposed to the reduction in CVD with HCQ in treatment of systemic lupus erythematous, rheumatoid arthritis, and other rheumatic diseases, safe usage of HCQ in COVID-19 patients is unclear; whereby, it is observed to result in QTc prolongation and Torsades de pointes even in patients with no underlying cardiovascular comorbidity. This is occasionally associated with sudden cardiac death or cardiac arrest; hence, its clinical efficacy needs further investigation by large-scale clinical trials.

Drug-drug interactions between COVID-19 treatments and antipsychotics drugs: integrated evidence from 4 databases and a systematic review

RATIONALE

Management of anxiety, delirium, and agitation cannot be neglected in coronavirus disease (COVID-19). Antipsychotics are usually used for the pharmacological management of delirium, and confusion and behavioral disturbances. The concurrent use of treatments for COVID-19 and antipsychotics should consider eventual drug-drug interactions OBJECTIVE: To systematically review evidence-based available on drug-drug interactions between COVID-19 treatments and antipsychotics.

EVIDENCE REVIEW

Three databases were consulted: Lexicomp® Drug Interactions, Micromedex® Solutions Drugs Interactions, and Liverpool© Drug Interaction Group for COVID-19 therapies. To acquire more information on QT prolongation and Torsade de Pointes (TdP), the CredibleMeds® QTDrugs List was searched. The authors made a recommendation agreed to by consensus. Additionally, a systematic review of drug-drug interactions between antipsychotics and COVID-19 treatment was conducted.

RESULTS

The main interactions between COVID-19 drugs and antipsychotics are the risk of QT-prolongation and TdP, and cytochromes P450 interactions. Remdesivir, baricinitib, and anakinra can be used concomitantly with antipsychotics without risk of drug-drug interaction (except for hematological risk with clozapine and baricinitib). Favipiravir only needs caution with chlorpromazine and quetiapine. Tocilizumab is rather safe to use in combination with antipsychotics. The most demanding COVID-19 treatments for coadministration with antipsychotics are chloroquine, hydroxychloroquine, azithromycin, and lopinavir/ritonavir because of the risk of QT prolongation and TdP and cytochromes interactions. The systematic review provides highly probable drug interaction between lopinavir/ritonavir plus quetiapine and ritonavir/indinavir plus risperidone.

CONCLUSIONS

Clinicians prescribing antipsychotics should be aware of the likely risk of drug-drug interaction with COVID-19 medication and may benefit from taking into account present recommendations of use to preserve patient safety.

Cracking the Chloroquine Conundrum: The Application of Defective UiO-66 Metal-Organic Framework Materials to Prevent the Onset of Heart Defects-In Vivo and In Vitro

In this study, we present a modulated synthesis nanocrystalline defective UiO-66 metal-organic framework as a potential chloroquine diphosphate (CQ) delivery system. Increasing the concentration of hydrochloric acid during the modulated synthesis resulted in a considerable increase of pore volume, which enhanced the CQ loading in CQ@UiO-66 composites. Drug release tests for CQ@UiO-66 composites have confirmed prolonged CQ release in comparison with pure CQ. In vivo tests on a Danio reiro model organism have revealed that CQ released from CQ@UiO-66 25% showed lower toxicity and fewer cardiotoxic effects manifested by cardiac malformations and arrhythmia in comparison to analogous doses of CQ. Cytotoxicity tests proved that the CQ loaded on the defective UiO-66 cargo resulted in increased viability of cardiac cells (H9C2) as compared to incubation with pure CQ. The experimental results presented here may be a step forward in the context of reducing the cardiotoxicity CQ.

Cardiovascular disease in patients with COVID-19: evidence from cardiovascular pathology to treatment

The coronavirus disease-2019 (COVID-19) caused by the novel coronavirus severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has rapidly developed into a global pneumonia pandemic. Cardiovascular disease is the major comorbidity of COVID-19 patients and is closely related to the severity of COVID-19. SARS-CoV-2 infection can directly or indirectly cause a series of cardiac complications, including acute myocardial injury and myocarditis, heart failure and cardiac arrest, arrhythmia, acute myocardial infarction, cardiogenic shock, Takotsubo cardiomyopathy, and coagulation abnormalities. Intensive research on the SARS-CoV-2-associated cardiovascular complications is urgently needed to elucidate its exact mechanism and to identify potential drug targets, which will help to formulate effective prevention and treatment strategies. Hence, this review will summarize recent progress regarding the effects of COVID-19 on the cardiovascular system and describe the underlying mechanism of cardiovascular injury caused by SARS-CoV-2.

Hydroxychloroquine for the treatment of COVID-19 and its potential cardiovascular toxicity: Hero or villain?

A variety of treatment modalities have been investigated since the beginning of the Coronavirus Disease-19 (COVID-19) pandemic. The use of antimalarials (hydroxychloroquine and chloroquine) for COVID-19 treatment and prevention has proven to be a cautionary tale for widespread, off-label use of a medication during a crisis. The investigation of antimalarials for COVID-19 has also been a driver for a deluge of scientific output in a short amount of time. In this narrative review, we detail the evidence for and against antimalarial use in COVID-19, starting with the early small observational studies that influenced strategies worldwide. We then contrast these findings to later published larger observational studies and randomized controlled trials. We detail the emerging possible cardiovascular risks associated with antimalarial use in COVID-19 and whether COVID-19-related outcomes and cardiovascular risks may differ for antimalarials used in rheumatic diseases.

Off-label use of chloroquine, hydroxychloroquine, azithromycin and lopinavir/ritonavir in COVID-19 risks prolonging the QT interval by targeting the hERG channel

Coronavirus disease-2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), poses an enormous challenge to the medical system, especially the lack of safe and effective COVID-19 treatment methods, forcing people to look for drugs that may have therapeutic effects as soon as possible. Some old drugs have shown clinical benefits after a few small clinical trials that attracted great attention. Clinically, however, many drugs, including those currently used in COVID-19, such as chloroquine, hydroxychloroquine, azithromycin, and lopinavir/ritonavir, may cause cardiotoxicity by acting on cardiac potassium channels, especially hERG channel through their off-target effects. The blocking of the hERG channel prolongs QT intervals on electrocardiograms; thus, it might induce severe ventricular arrhythmias and even sudden cardiac death. Therefore, while focusing on the efficacy of COVID-19 drugs, the fact that they block hERG channels to cause arrhythmias cannot be ignored. To develop safer and more effective drugs, it is necessary to understand the interactions between drugs and the hERG channel and the molecular mechanism behind this high affinity. In this review, we focus on the biochemical and molecular mechanistic aspects of drug-related blockade of the hERG channel to provide insights into QT prolongation caused by off-label use of related drugs in COVID-19, and hope to weigh the risks and benefits when using these drugs.