RESUMO
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has given rise to a pandemic of unprecedented proportions in the modern era because of its highly contagious nature and impact on human health and society: coronavirus disease 2019 (COVID-19). Patients with cardiovascular (CV) risk factors and established CV disease (CVD) are among those initially identified at the highest risk for serious complications, including death. Subsequent studies have pointed out that patients with cancer are also at high risk for a critical disease course. Therefore, the most vulnerable patients are seemingly those with both cancer and CVD, and a careful, unified approach in the evaluation and management of this patient population is especially needed in times of the COVID-19 pandemic. This review provides an overview of the unique implications of the viral outbreak for the field of cardio-oncology and outlines key modifications in the approach to this ever-increasing patient population. These modifications include a shift toward greater utilization of cardiac biomarkers and a more focused CV imaging approach in the broader context of modifications to typical practice pathways. The goal of this strategic adjustment is to minimize the risk of SARS-CoV-2 infection (or other future viral outbreaks) while not becoming negligent of CVD and its important impact on the overall outcomes of patients who are being treated for cancer.
Assuntos
Antineoplásicos/efeitos adversos , COVID-19/complicações , Doenças Cardiovasculares/etiologia , Infecção Hospitalar/prevenção & controle , Neoplasias/complicações , Neoplasias/terapia , Antraciclinas/efeitos adversos , COVID-19/fisiopatologia , COVID-19/prevenção & controle , COVID-19/transmissão , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/terapia , Humanos , Inibidores de Proteassoma/efeitos adversos , Inibidores de Proteínas Quinases/efeitos adversos , Radioterapia/efeitos adversos , Receptor ErbB-2/antagonistas & inibidores , Encaminhamento e Consulta , SARS-CoV-2 , Trastuzumab/efeitos adversosRESUMO
OBJECTIVE: To assess the effect of relacorilant, a selective glucocorticoid receptor modulator under investigation for the treatment of patients with endogenous hypercortisolism (Cushing syndrome [CS]), on the heart rate-corrected QT interval (QTc). METHODS: Three clinical studies of relacorilant were included: (1) a first-in-human, randomized, placebo-controlled, ascending-dose (up to 500 mg of relacorilant) study in healthy volunteers; (2) a phase 1 placebo- and positive-controlled thorough QTc (TQT) study of 400 and 800 mg of relacorilant in healthy volunteers; and (3) a phase 2, open-label study of up to 400 mg of relacorilant administered daily for up to 16 weeks in patients with CS. Electrocardiogram recordings were taken, and QTc change from baseline (ΔQTc) was calculated. The association of plasma relacorilant concentration with the effect on QTc in healthy volunteers was assessed using linear mixed-effects modeling. RESULTS: Across all studies, no notable changes in the electrocardiogram parameters were observed. At all time points and with all doses of relacorilant, including supratherapeutic doses, ΔQTc was small, generally negative, and, in the placebo-controlled studies, similar to placebo. In the TQT study, placebo-corrected ΔQTc with relacorilant was small and negative, whereas placebo-corrected ΔQTc with moxifloxacin positive control showed rapid QTc prolongation. These results constituted a negative TQT study. The model-estimated slopes of the concentration-QTc relationship were slightly negative, excluding an association of relacorilant with prolonged QTc. CONCLUSION: At all doses studied, relacorilant consistently demonstrated a lack of QTc prolongation in healthy volunteers and patients with CS, including in the TQT study. Ongoing phase 3 studies will help further establish the overall benefit-risk profile of relacorilant.
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Síndrome de Cushing , Síndrome do QT Longo , Humanos , Estudos Cross-Over , Síndrome de Cushing/tratamento farmacológico , Relação Dose-Resposta a Droga , Método Duplo-Cego , Eletrocardiografia , Voluntários Saudáveis , Síndrome do QT Longo/induzido quimicamente , Síndrome do QT Longo/tratamento farmacológico , Moxifloxacina , Receptores de Glucocorticoides , Ensaios Clínicos Controlados Aleatórios como Assunto , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como AssuntoRESUMO
One objective of meta-analysis, which synthesizes evidence across multiple studies, is to assess the consistency and investigate the heterogeneity across studies. In this project, we performed a meta-analysis on moxifloxacin (positive control in QT assessment studies) data to characterize the exposure-response relationship and determine the safety margin associated with 10-msec QTc effects for moxifloxacin based on 26 thorough QT studies submitted to the FDA. Multiple meta-analysis methods were used (including two novel methods) to evaluate the exposure-response relationship and estimate the critical concentration and the corresponding confidence interval of moxifloxacin associated with a 10-msec QTc effect based on the concentration-QTc models. These meta-analysis methods (aggregate data vs. individual participant data; fixed effect vs. random effect) were compared in terms of their precision and robustness. With the selected meta-analysis method, we demonstrated the homogeneity and heterogeneity of the moxifloxacin concentration-QTc relationship in studies. We also estimated the critical concentration of moxifloxacin that can be used to calculate the hERG safety margin of this drug.
RESUMO
In recent decades, drug development costs have increased by approximately a hundredfold, and yet about 1 in 7 licensed drugs are withdrawn from the market, often due to cardiotoxicity. This review considers whether technologies using human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) could complement existing assays to improve discovery and safety while reducing socioeconomic costs and assisting with regulatory guidelines on cardiac safety assessments. We draw on lessons from our own work to suggest a panel of 12 drugs that will be useful in testing the suitability of hiPSC-CM platforms to evaluate contractility. We review issues, including maturity versus complexity, consistency, quality, and cost, while considering a potential need to incorporate auxiliary approaches to compensate for limitations in hiPSC-CM technology. We give examples on how coupling hiPSC-CM technologies with Cas9/CRISPR genome engineering is starting to be used to personalize diagnosis, stratify risk, provide mechanistic insights, and identify new pathogenic variants for cardiovascular disease.
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Cardiotoxicidade/prevenção & controle , Descoberta de Drogas/métodos , Miócitos Cardíacos/efeitos dos fármacos , Animais , Sistemas CRISPR-Cas/genética , Desenvolvimento de Medicamentos/métodos , Engenharia Genética , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Miócitos Cardíacos/citologia , Medicina de Precisão/métodosRESUMO
Among various cardiac safety concerns, proarrhythmia risks, including QT prolongation leading to Torsade de Pointes, is one of major cause for drugs being withdrawn (~45% 1975-2007). Preclinical study requires the evaluation of proarrhythmia using in silico, in vitro, and/or animal models. Considering that the primary consumers of prescription drugs are elderly patients, applications of "aging-in-a-dish" models would be appropriate for screening proarrhythmia risks. However, acquiring such models, including cardiomyocytes (CMs) derived from induced pluripotent stem cells (iPSCs), presents extensive challenges. We proposed the hypothesis that CMs differentiated from iPSCs derived from Hutchinson-Gilford progeria syndrome (HGPS, progeria) patients, an ultra-rare premature aging syndrome, can mimic the phenotypes of aging CMs. Our objective, therefore, was to examine this hypothesis by analyzing the response of 11 reference compounds utilized by the Food and Drug Administration (FDA)'s Comprehensive in vitro Proarrhythmia Assay (CiPA) using progeria and control CMs. As a sensitive surrogate marker of modulating cardiac excitation-contraction coupling, we evaluated drug-induced changes in calcium transient (CaT). We observed that the 80% CaT peak duration in the progeria CMs (0.98 ± 0.04 s) was significantly longer than that of control CMs (0.70 ± 0.05 s). Furthermore, when the progeria CMs were subjected to four doses of 11 compounds from low-, intermediate-, and high-risk categories, they demonstrated greater arrhythmia susceptibility than control cells, as shown through six-parameter CaT profile analyses. We also employed the regression analysis established by CiPA to classify the 11 reference compounds and compared proarrhythmia susceptibilities between the progeria and control CMs. This analysis revealed a greater proarrhythmia susceptibility in the progeria CMs compared to the control CMs. Interestingly, in both CMs, the compounds categorized as low risk did not exceed the safety risk threshold of 0.8. In conclusion, our study demonstrates increased proarrhythmia sensitivity in progeria CMs when tested with reference compounds. Future studies are needed to analyze underlying mechanisms and further validate our findings using a larger array of reference compounds.
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Células-Tronco Pluripotentes Induzidas , Progéria , Animais , Miócitos Cardíacos/fisiologia , Preparações Farmacêuticas , EnvelhecimentoRESUMO
Mass drug administration (MDA) with monthly dihydroartemisinin-piperaquine (DHA-PQP) appears useful in malaria control and elimination strategies. Determining the relationship between consecutive piperaquine phosphate (PQP) exposure and its impact on QT interval prolongation is a key safety consideration for MDA campaigns. Healthy volunteers from Papua New Guinea received a 3-day course of DHA-PQP (2.1/17.1 mg/kg) monthly for 3 consecutive months in a single arm longitudinal study. Plasma PQP concentrations were measured after the third dose of each course (at 52-54 h) and at 0 h of course 3. Twelve-lead electrocardiographic readings were conducted at 0 h, 48 h, 52 h, and day 7 of each course. QT interval corrected by Fridericia's formula (QTcF) was measured at each time point. A pharmacokinetic-pharmacodynamic model using nonlinear mixed effects models was developed to correlate PQP concentrations with QTcF. Ten thousand female and 10,000 male individuals were simulated at each treatment course. Eighty-two participants were included; mean age was 28.3 years (standard deviation [SD] ±12.3 years), and 36 (44%) were female. Pharmacokinetic-pharmacodynamic models were determined with 290 PQP concentrations and 868 QTcF observations. The average baseline QTcF was 392 ms with a between-subject variability SD ±14.4 ms and between-occasion variability SD ±3.64 ms. From the population modeled, only 0.08% of males and 0.45% of females would be at risk of an absolute QTcF of >500 ms. DHA-PQP is safe at standard doses in consecutive months, and the likelihood of severe cardiac events occurring during an MDA campaign is very low. This study has been registered at ClinicalTrials.gov under identifier NCT02605720.
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Antimaláricos , Malária Falciparum , Piperazinas , Quinolinas , Adulto , Antimaláricos/efeitos adversos , Antimaláricos/farmacocinética , Antimaláricos/farmacologia , Artemisininas/efeitos adversos , Artemisininas/farmacocinética , Artemisininas/farmacologia , Feminino , Voluntários Saudáveis , Humanos , Síndrome do QT Longo/induzido quimicamente , Estudos Longitudinais , Malária Falciparum/tratamento farmacológico , Masculino , Papua Nova Guiné , Piperazinas/efeitos adversos , Piperazinas/farmacocinética , Piperazinas/farmacologia , Quinolinas/efeitos adversos , Quinolinas/farmacocinética , Quinolinas/farmacologiaRESUMO
AIMS: Given the increasing emergence of drug resistance in Plasmodium, new antimalarials are urgently required. P218 is an aminopyridine that inhibits dihydrofolate reductase being developed as a malaria chemoprotective drug. Assessing the effect of new compounds on cardiac intervals is key during early drug development to determine their cardiac safety. METHODS: This double-blind, randomized, placebo-controlled, parallel group study evaluated the effect of P218 on electrocardiographic parameters following oral administration of seven single-ascending doses up to 1000 mg in 56 healthy volunteers. Participants were randomized to treatment or placebo at a 3:1 ratio. P218 was administered in the fasted state with standardized lunch served 4 hours after dosing. 12-lead ECGs were recorded in triplicate at regular intervals on the test day, and at 48, 72, 120, 168, 192 and 240 hours thereafter. Blood samples for pharmacokinetic evaluations were collected at similar time points. Concentration-effect modelling was used to assess the effect of P218 and its metabolites on cardiac intervals. RESULTS: Concentration-effect analysis showed that P218 does not prolong the QTcF, J-Tpeak or TpTe interval at all doses tested. No significant changes in QRS or PR intervals were observed. Two-sided 90% confidence intervals of subinterval effects of P218 and its metabolites were consistently below the regulatory concern threshold for all doses. Study sensitivity was confirmed by significant shortening of QTcF after a meal. CONCLUSION: Oral administration of P218 up to 1000 mg does not prolong QTcF and does not significantly change QRS or PR intervals, suggesting low risk for drug-induced proarrhythmia.
Assuntos
Antimaláricos , Malária , Antimaláricos/efeitos adversos , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Eletrocardiografia , Voluntários Saudáveis , Frequência Cardíaca , Humanos , Malária/tratamento farmacológico , MasculinoRESUMO
WHAT IS KNOWN AND OBJECTIVE: Fenspiride, a drug that had been used for decades for the treatment of respiratory diseases, was recently withdrawn from the market due to the potential risk of QT prolongation and proarrhythmia. This is the first such withdrawal for many years and hence poses a question whether such risk could have been predicted and to what degree non-drug-specific parameters play a role in the reported QT prolongation and cases of TdP. The study aim was to test various 'what-if' scenarios to assess the influence of age, gender, heart rate, and plasma potassium concentration on QT interval prolongation due to various doses of fenspiride with the use of mechanistic mathematical modelling. METHODS: Concentration-time profiles were simulated with the use of a PBPK model developed based on published physico-chemical data, data from in vitro ADME experiments, and in vivo PK study results. Pharmacodynamic effect, that is, drug-triggered pseudoECG signal modification was simulated using a biophysically detailed model of human cardiac myocytes. Analysis of the qNet metric was also performed to classify proarrhythmic risk related to fenspiride. RESULTS: In the simulation study, arrhythmia was not observed even in the 'what-if' scenarios with extreme exposure, age, heart rate, and plasma potassium concentration. The qNet metric value positioned fenspiride in the intermediate risk class. WHAT IS NEW AND CONCLUSION: It can be hypothesized that the clinically observed arrhythmia cases were not directly caused by fenspiride alone but a combination of multiple factors, including comedications.
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Síndrome do QT Longo , Torsades de Pointes , Humanos , Torsades de Pointes/induzido quimicamente , Síndrome do QT Longo/induzido quimicamente , Arritmias Cardíacas/induzido quimicamente , Frequência CardíacaRESUMO
Cardiotoxicity is smong the main safety problems of drugs in clinical application. In recent years, traditional Chinese medicine has been gradually emphasized and studies on the evaluation of cardiac safety and prevention of cardiotoxicity of Chinese medicine have been on the rise, particularly the cardiotoxic Chinese medicine or the Chinese medicine components targeting cardiotoxicity. As for the research methods for cardiac safety evaluation of Chinese medicine, this review introduces the related clinical indexes and cell and animal models. As to the improvement of heart safety, this study reviews the material basis and mechanism of cardiotoxic Chinese medicines as well as the alleviation of cardiotoxicity by controlling the content of toxic compounds and changing dosage form, processing method, and compatibility of Chinese medicine. In addition, the effective components and mechanisms of prescriptions and active compounds in Chinese medicine for preventing and treating cardiotoxicity induced by chemotherapeutic drugs in recent years were summarized. This review is expected to serve as a reference for cardiac safety evaluation and clinical rational application of Chinese medicine.
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Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Animais , Cardiotoxicidade/prevenção & controleRESUMO
Zoliflodacin is a novel spiropyrimidinetrione antibiotic being developed as single oral dose treatment to address the growing global threat of Neisseria gonorrhoeae. To evaluate the cardiac safety of zoliflodacin, a thorough QT/QTc (TQT) study was performed in healthy subjects. In this randomized, double-blind, placebo-controlled, 4-period crossover study, 72 subjects in a fasted state received a single dose of zoliflodacin at 2 g (therapeutic), zoliflodacin at 4 g (supratherapeutic), placebo, and moxifloxacin at 400 mg as a positive comparator. Cardiac repolarization was measured by duration of the corrected QT interval by Fridericia's formula (QTcF). At each time point up to 24 h after zoliflodacin administration, the upper limit of the one-sided 95% confidence interval (CI) for the placebo-corrected change from the predose baseline in QTcF (ΔΔQTcF) was less than 10 ms, indicating an absence of a clinically meaningful increase in QT prolongation. The lower limit of the one-sided multiplicity-adjusted 95% CI of ΔΔQTcF for moxifloxacin was longer than 5 ms at four time points from 1 to 4 h after dosing, demonstrating adequate sensitivity of the QTc measurement. There were no clinically significant effects on heart rate, PR and QRS intervals, electrocardiogram (ECG) morphology, or laboratory values. Treatment-emergent adverse events (AEs) were mild or moderate in severity and transient. This was a negative TQT study according to regulatory guidelines (E14) and confirms that a single oral dose of zoliflodacin is safe and well tolerated. These findings suggest that zoliflodacin is not proarrhythmic and contribute to the favorable assessment of cardiac safety for a single oral dose of zoliflodacin. (This study has been registered at ClinicalTrials.gov under registration no. NCT03613649.).
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Gonorreia , Síndrome do QT Longo , Adulto , Barbitúricos , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Eletrocardiografia , Fluoroquinolonas , Voluntários Saudáveis , Frequência Cardíaca , Humanos , Isoxazóis , Morfolinas , Oxazolidinonas , Compostos de EspiroRESUMO
PURPOSE: HER2-targeted therapies are associated with cardiotoxicity which is usually asymptomatic and reversible. We report the updated cardiac safety assessment of patients with compromised heart function receiving HER2-targeted therapy for breast cancer, enrolled in the SAFE-HEaRt trial, at a median follow-up of 3.5 years. METHODS: Thirty patients with stage I-IV HER2-positive breast cancer receiving trastuzumab with or without pertuzumab, or ado-trastuzumab emtansine (T-DM1), with asymptomatic LVEF (left ventricular ejection fraction) 40-49%, were started on cardioprotective medications, with the primary endpoint being completion of HER2-targeted therapy without cardiac events (CE) or protocol-defined asymptomatic worsening of LVEF. IRB-approved follow-up assessment included 23 patients. RESULTS: Median follow-up as of June 2020 is 42 months. The study met its primary endpoint with 27 patients (90%) completing their HER2-targeted therapies without cardiac issues. Of the 23 evaluable patients at long-term f/u, 14 had early stage breast cancer, and 9 had metastatic disease, 8 of whom remained on HER2-targeted therapies. One patient developed symptomatic heart failure with no change in LVEF. There were no cardiac deaths. The mean LVEF improved to 52.1% from 44.9% at study baseline, including patients who remained on HER2-targeted therapy, and those who received prior anthracyclines. CONCLUSIONS: Long-term follow-up of the SAFE-HEaRt study continues to provide safety data of HER2-targeted therapy use in patients with compromised heart function. The late development of cardiac dysfunction is uncommon and continued multi-disciplinary oncologic and cardiac care of patients is vital for improved patient outcomes.
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Neoplasias da Mama , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias da Mama/complicações , Neoplasias da Mama/tratamento farmacológico , Feminino , Seguimentos , Humanos , Receptor ErbB-2/genética , Volume Sistólico , Trastuzumab/efeitos adversos , Função Ventricular EsquerdaRESUMO
The circadian rhythm of cardiac electrophysiology is dependent on many physiological and biochemical factors. Provided, that models describing the circadian patterns of cardiac activity and/or electrophysiology which have been verified to the acceptable level, modeling and simulation can give answers to many of heart chronotherapy questions. The aim of the study was to assess the performance of the circadian models implemented in Cardiac Safety Simulator v 2.2 (Certara, Sheffield, UK) (CSS), as well as investigate the influence ofcircadian rhythms on the simulation results in terms of cardiac safety. The simulations which were run in CSS accounted for inter-individual and intra-individual variability. Firstly, the diurnal variations in QT interval length in a healthy population were simulated accounting for heart rate (HR) circadian changes alone, or with concomitant diurnal variations of plasma ion concentrations. Next, tolterodine was chosen as an exemplary drug for PKPD modelling exercise to assess the role of circadian rhythmicity in the prediction of drug effects on QT interval. The results of the simulations were in line with clinical observations, what can serve as a verification of the circadian models implemented in CSS. Moreover, the results have suggested that the circadian variability of the electrolytes balance is the main factor influencing QT circadian pattern. The fluctuation of ion concentration increases the intra-subject variability of predicted drug-triggered QT corrected for HR (QTc) prolongation effect and, in case of modest drug effect on QTc interval length, allows to capture this effect.
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Ritmo Circadiano/fisiologia , Eletrólitos/sangue , Frequência Cardíaca/fisiologia , Síndrome do QT Longo/prevenção & controle , Modelos Biológicos , Adolescente , Adulto , Estudos de Casos e Controles , Cronofarmacocinética , Simulação por Computador , Eletrocardiografia , Feminino , Voluntários Saudáveis , Frequência Cardíaca/efeitos dos fármacos , Humanos , Síndrome do QT Longo/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
Background and Objectives: There is evidence for ketamine efficacy in treatment-resistant depression (TRD). Several safety and tolerability concerns arise that some psychotropic agents may provide blood pressure or/and heart rate alterations. The aim of this study is to review blood pressure measurements in course of the treatment with ketamine on treatment refractory inpatients with somatic comorbidities in the course of MDD and BP. Materials and Methods: The study population of 49 patients comprised MDD and BP subjects treated with ketamine registered in the naturalistic observational protocol of treatment-resistant mood disorders (NCT04226963). Results: The conducted analysis showed that among people suffering from hypertension there is a higher increase in systolic blood pressure (RR) after infusion 2 (p = 0.004) than among people who do not suffer from hypertension. Patients with hypertension have a higher increase in diastolic RR compared to those not suffering from hypertension (p = 0,038). Among the subjects with diabetes mellitus, significant differences occurred for infusions 2 (p = 0.020), 7 (p = 0.020), and 8 (p = 0.035) for heart rate (HR), compared to subjects without diabetes mellitus. A higher increase in diastolic RR was noted in the group of subjects suffering from diabetes mellitus (p = 0.010) compared to those who did not. In the hyperlipidemic patients studied, a significantly greater decrease in HR after infusion 5 (p = 0.031) and systolic RR after infusion 4 (p = 0.036) was noted compared to nonpatients. People after a stroke had significantly higher increases in diastolic RR after infusions 4 (p = 0.021) and 6 (p = 0.001) than those who did not have a stroke. Patients suffering from epilepsy had a significantly greater decrease in systolic RR after the 8th infusion (p = 0.017) compared to those without epilepsy. Limitations: The study may be underpowered due to the small sample size. The observations apply to inhomogeneous TRD population in a single-site with no blinding and are limited to the acute administration. Conclusions: This study supports evidence for good safety and tolerability profile for short-term IV ketamine use in TRD treatment. However, risk mitigation measures are to be considered in patients with metabolic and cardiovascular comorbidities.
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Transtorno Depressivo Resistente a Tratamento , Ketamina , Comorbidade , Depressão , Transtorno Depressivo Resistente a Tratamento/tratamento farmacológico , Transtorno Depressivo Resistente a Tratamento/epidemiologia , Humanos , Infusões Intravenosas , Ketamina/efeitos adversosRESUMO
Higher chloroquine doses can effectively treat up to 93 to 96% of malaria infections caused by Plasmodium falciparum carrying the resistance-conferring chloroquine resistance transporter (pfcrt) 76T allele. The tolerability of 50 (double the standard dose) and 70 mg/kg total chloroquine doses were assessed in this study. Fifteen 4- to 8-year-old children with uncomplicated malaria were given 10 mg/kg of chloroquine twice daily for 2 days and 5 mg/kg twice daily on the third day. Fifteen additional children were given 5 mg/kg twice daily for 2 more days. Chloroquine concentrations, blood pressure, electrocardiograms (ECGs), parasite density, and adverse events were assessed until day 28. Both dosages were well tolerated, and symptoms resolved by day 3 in parallel with increasing chloroquine concentrations. The median corrected QT (QTc) interval was 12 to 26 ms higher at expected peak concentrations than at day 0 (P < 0.001). Pfcrt 76T was associated with delayed parasite clearance. Day 28 clinical and parasitological responses against P. falciparum with pfcrt 76T were 57% (4/7) and 67% (4/6) after treatment with 50 and 70 mg/kg, respectively. Dosages were well tolerated, and no severe cardiac adverse events occurred. The QTc interval increase was similar to that found in adults taking 25 mg/kg of chloroquine. (This study has been registered at ClinicalTrials.gov under identifier NCT01814423.).
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Antimaláricos/administração & dosagem , Cloroquina/administração & dosagem , Resistência a Medicamentos/genética , Malária Falciparum/tratamento farmacológico , Proteínas de Membrana Transportadoras/genética , Plasmodium falciparum/efeitos dos fármacos , Proteínas de Protozoários/genética , Antimaláricos/efeitos adversos , Criança , Pré-Escolar , Cloroquina/efeitos adversos , Relação Dose-Resposta a Droga , Eletrocardiografia , Feminino , Expressão Gênica , Guiné-Bissau , Humanos , Síndrome do QT Longo/induzido quimicamente , Síndrome do QT Longo/diagnóstico , Síndrome do QT Longo/fisiopatologia , Malária Falciparum/parasitologia , Masculino , Proteínas de Membrana Transportadoras/metabolismo , Carga Parasitária , Plasmodium falciparum/genética , Plasmodium falciparum/crescimento & desenvolvimento , Proteínas de Protozoários/metabolismo , Resultado do TratamentoRESUMO
A series of 2-aryl-2-(pyridin-2-yl)acetamides were synthesized and screened for their anticonvulsant activity in animal models of epilepsy. The compounds were broadly active in the 'classical' maximal electroshock seizure (MES) and subcutaneous Metrazol (scMET) tests as well as in the 6 Hz and kindling models of pharmacoresistant seizures. Furthermore, the compounds showed good therapeutic indices between anticonvulsant activity and motor impairment. Structure-activity relationship (SAR) trends clearly showed the highest activity resides in unsubstituted phenyl derivatives or compounds having ortho- and meta- substituents on the phenyl ring. The 2-aryl-2-(pyridin-2-yl)acetamides were derived by redesign of the cardiotoxic sodium channel blocker Disopyramide (DISO). Our results show that the compounds preserve the capability of the parent compound to inhibit voltage gated sodium currents in patch-clamp experiments; however, in contrast to DISO, a representative compound from the series 1 displays high levels of cardiac safety in a panel of in vitro and in vivo experiments.
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Acetamidas/uso terapêutico , Anticonvulsivantes/uso terapêutico , Disopiramida/uso terapêutico , Convulsões/tratamento farmacológico , Acetamidas/administração & dosagem , Acetamidas/química , Animais , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/química , Disopiramida/administração & dosagem , Disopiramida/química , Relação Dose-Resposta a Droga , Eletrochoque , Feminino , Injeções Intraperitoneais , Injeções Subcutâneas , Masculino , Camundongos , Estrutura Molecular , Pentilenotetrazol/administração & dosagem , Ratos , Ratos Wistar , Convulsões/induzido quimicamente , Relação Estrutura-AtividadeRESUMO
Cardiac conduction disturbances are linked with arrhythmia development. The concept of safety factor (SF) has been derived to describe the robustness of conduction, but the usefulness of this metric has been constrained by several limitations. For example, due to the difficulty of measuring the necessary input variables, SF calculations have only been applied to synthetic data. Moreover, quantitative validation of SF is lacking; specifically, the practical meaning of particular SF values is unclear, aside from the fact that propagation failure (i.e., conduction block) is characterized by SFâ¯<â¯1. This study aims to resolve these limitations for our previously published SF formulation and explore its relationship to relevant electrophysiological properties of cardiac tissue. First, HL-1 cardiomyocyte monolayers were grown on multi-electrode arrays and the robustness of propagation was estimated using extracellular potential recordings. SF values reconstructed purely from experimental data were largely between 1 and 5 (up to 89.1% of sites characterized). This range is consistent with values derived from synthetic data, proving that the formulation is sound and its applicability is not limited to analysis of computational models. Second, for simulations conducted in 1-, 2-, and 3-dimensional tissue blocks, we calculated true SF values at locations surrounding the site of current injection for sub- and supra-threshold stimuli and found that they differed from values estimated by our SF formulation by <10%. Finally, we examined SF dynamics under conditions relevant to arrhythmia development in order to provide physiological insight. Our analysis shows that reduced conduction velocity (Θ) caused by impaired intrinsic cell-scale excitability (e.g., due to sodium current a loss-of-function mutation) is associated with less robust conduction (i.e., lower SF); however, intriguingly, Θ variability resulting from modulation of tissue scale conductivity has no effect on SF. These findings are supported by analytic derivation of the relevant relationships from first principles. We conclude that our SF formulation, which can be applied to both experimental and synthetic data, produces values that vary linearly with the excess charge needed for propagation. SF calculations can provide insights helpful in understanding the initiation and perpetuation of cardiac arrhythmia.
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Arritmias Cardíacas/fisiopatologia , Fenômenos Eletrofisiológicos , Modelos Cardiovasculares , Contração Miocárdica/fisiologia , Potenciais de Ação/fisiologia , Animais , Arritmias Cardíacas/epidemiologia , Bloqueio Cardíaco/fisiopatologia , Frequência Cardíaca/fisiologia , Humanos , Contração Miocárdica/genética , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/fisiologia , Condutividade TérmicaRESUMO
PURPOSE: HER2-targeted therapies have substantially improved the outcome of patients with breast cancer, however, they can be associated with cardiac toxicity. Guidelines recommend holding HER2-targeted therapies until resolution of cardiac dysfunction. SAFE-HEaRt is the first trial that prospectively tests whether these therapies can be safely administered without interruptions in patients with cardiac dysfunction. METHODS: Patients with stage I-IV HER2-positive breast cancer candidates for trastuzumab, pertuzumab or ado-trastuzumab emtansine (TDM-1), with left ventricular ejection fraction (LVEF) 40-49% and no symptoms of heart failure (HF) were enrolled. All patients underwent cardiology visits, serial echocardiograms and received beta blockers and ACE inhibitors unless contraindicated. The primary endpoint was completion of the planned HER2-targeted therapies without developing either a cardiac event (CE) defined as HF, myocardial infarction, arrhythmia or cardiac death or significant asymptomatic worsening of LVEF. The study was considered successful if planned oncology therapy completion rate was at least 30%. RESULTS: Of 31 enrolled patients, 30 were evaluable. Fifteen patients were treated with trastuzumab, 14 with trastuzumab and pertuzumab, and 2 with TDM-1. Mean LVEF was 45% at baseline and 46% at the end of treatment. Twenty-seven patients (90%) completed the planned HER2-targeted therapies. Two patients experienced a CE and 1 had an asymptomatic worsening of LVEF to ≤ 35%. CONCLUSION: This study provides safety data of HER2-targeted therapies in patients with breast cancer and reduced LVEF while receiving cardioprotective medications and close cardiac monitoring. Our results demonstrate the importance of collaboration between cardiology and oncology providers to allow for delivery of optimal oncologic care to this unique population.
Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Terapia de Alvo Molecular/efeitos adversos , Receptor ErbB-2/metabolismo , Disfunção Ventricular Esquerda/tratamento farmacológico , Ado-Trastuzumab Emtansina , Adulto , Idoso , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Neoplasias da Mama/metabolismo , Feminino , Humanos , Maitansina/administração & dosagem , Maitansina/efeitos adversos , Maitansina/análogos & derivados , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Projetos Piloto , Estudos Prospectivos , Trastuzumab/administração & dosagem , Trastuzumab/efeitos adversos , Resultado do Tratamento , Disfunção Ventricular Esquerda/induzido quimicamente , Disfunção Ventricular Esquerda/fisiopatologiaRESUMO
AIMS: Cladribine tablets have shown significant efficacy for the treatment of relapsing multiple sclerosis, a chronic and debilitating immune-mediated disorder. This study was conducted to examine acute and/or cumulative effects of cladribine tablets 10 mg (3.5 or 5.25 mg/kg cumulative dose over 2 years) on heart rate, AV conduction and cardiac repolarization in patients with relapsing-remitting multiple sclerosis (RRMS). METHODS: CLARITY was a 96-week, double-blind, placebo-controlled, multicentre trial which evaluated the safety and efficacy of cladribine tablets 3.5 and 5.25 mg/kg body weight in patients with RRMS. A total of 135 patients were included in the ECG substudy, providing a total of 1534 post-dose ECGs. ECG data were collected 15 minutes pre-dose and between 0.5 and 3 hours post-dose at pre-study evaluation, study Day 1 and Weeks 5, 9, 13, 48 and 52. RESULTS: For cladribine tablets 3.5 mg/kg, the maximum change in placebo-adjusted post-dose QTcF vs. visit-baseline (BL) was -0.42 ms (90% CI: -3.61-4.44) at Week 1 (acute effects), and 3.20 ms (90% CI: -0.08-6.33) for cladribine tablets 5.25 mg/kg. The greatest observed differences in post-dose QTcF vs. study BL occurred at Week 48 for both the 3.5 and 5.25 mg/kg doses of cladribine tablets with 5.99 ms (90% CI: 0.53-11.44) and 8.74 ms (90% CI: 3.18-14.31), respectively. No significant changes were observed in T-wave morphology in either treatment group. CONCLUSIONS: Cladribine tablets 3.5 mg/kg (approved dose in Europe/other regions) did not confer clinically meaningful effects on heart rate, AV conduction and ventricular repolarization.
Assuntos
Cladribina/administração & dosagem , Sistema de Condução Cardíaco/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Imunossupressores/administração & dosagem , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Adulto , Cladribina/efeitos adversos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Imunossupressores/efeitos adversos , Masculino , Pessoa de Meia-Idade , ComprimidosRESUMO
The electrocardiogram is often used as an efficacy endpoint for comparing new drugs or as an indicator for cardiovascular safety in both studies of arrhythmic and non-arrhythmic novel drugs. The FDA ECG Warehouse data are owned by the submitting entities, generally pharmaceutical company manufacturers. However, a subset of these ECG data was released with permission from the data owners to the CSRC for access by investigators, equipment manufacturers and algorithm developers for CSRC-approved research and development studies. This article provides an overview of the Cardiac Safety Research Consortium (CSRC) ECG Warehouse, including data availability, completed and ongoing projects, as well as future growth potential amidst an ever expanding FDA ECG Warehouse. Given that current ICH E14 guidelines request that sponsors submitting new drug applications assess the effects on the QT interval using a thorough QT (TQT) or dose-ranging study with concentration-QT analysis during early clinical development to assess cardiac risk, developing novel methods to determine cardiovascular safety, as well as understanding current ECG collection and analysis methods are prudent. The ability to utilize previously collected ECG data for secondary analyses improves cardiovascular safety by multiplying the scientific contribution of the original research.
Assuntos
Eletrocardiografia , Síndrome do QT Longo , Algoritmos , HumanosRESUMO
Mass drug administration (MDA) of sequential rounds of antimalarial drugs is being considered for use as a tool for malaria elimination. As an effective and long-acting antimalarial, dihydroartemisinin-piperaquine (DHA-PQP) appears to be suitable as a candidate for MDA. However, the absence of cardiac safety data following repeated administration hinders its use in the extended schedules proposed for MDA. We conducted an interventional study in Lihir Island, Papua New Guinea, using healthy individuals age 3 to 60 years who received a standard 3-day course of DHA-PQP on 3 consecutive months. Twelve-lead electrocardiography (ECG) readings were conducted predose and 4 h after the final dose of each month. The primary safety endpoint was QT interval correction (QTc using Fridericia's correction [QTcF]) prolongation from baseline to 4 h postdosing. We compared the difference in prolongations between the third course postdose and the first course postdose. Of 84 enrolled participants, 69 (82%) participants completed all treatment courses and ECG measurements. The average increase in QTcF was 19.6 ms (standard deviation [SD], 17.8 ms) and 17.1 ms (SD, 17.1 ms) for the first-course and third-course postdosing ECGs risk difference, -2.4 (95% confidence interval [95% CI], -6.9 to 2.1; P = 0.285), respectively. We recorded a QTcF prolongation of >60 ms from baseline in 3 (4.3%) and 2 (2.9%) participants after the first course and third course (P = 1.00), respectively. No participants had QTcF intervals of >500 ms at any time point. Three consecutive monthly courses of DHA-PQP were as safe as a single course. The absence of cumulative cardiotoxicity with repeated dosing supports the use of monthly DHA-PQP as part of malaria elimination strategies.