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546
result(s) for
"Long QT Syndrome - physiopathology"
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Approach to Evaluating QT Prolongation of Quetiapine Fumarate in Late Stage of Clinical Development Using Concentration-QTc Modeling and Simulation in Japanese Patients With Bipolar Disorder
2020
Quetiapine has been reported to prolong the QT interval, and has been used as a positive control in thorough QT studies. The objective of the present study was to evaluate, in the late stages of clinical development, the QT-prolongation effects of the extended-release (XR) formulation of quetiapine at the approved dose in Japanese patients with bipolar disorder, using concentration–QT modeling and simulation.
Plasma concentrations of quetiapine and 4 of its metabolites (M1, M2, M4, and M5), and the QT interval corrected using the Fridericia formula (QTcF), were used for the concentration–QT analysis. Data from intensive electrocardiogram monitoring at predose and at 4, 6, 10, and 24 h after the administration of the last dose were pooled from a Phase I trial (6949-CL-0006) and from sparse sampling in late-stage clinical trials (6949-CL-0005, -0021, −0022, and −0023) in Japanese patients (N = 505). The upper limit of 1-sided 95% confidence interval (CI) of the changes from baseline in QTcF (ΔQTcF) at the geometric mean Cmax of a therapeutic dose of 300 mg once daily was predicted using a linear mixed-effects model, with the intercept as a random effect specifying a subject effect.
For quetiapine and M2, but not M1, M4, or M5, positive slopes were observed between ΔQTcF and concentration. The predicted upper limits of the 1-sided 95% CIs did not exceed the regulatory threshold of 10 msec. Therefore, QTc prolongation is unlikely to be clinically relevant at the approved dose of quetiapine XR.
In this pooled data analysis of the QT-prolongation effects of the quetiapine XR, positive relationships between ΔQTcF and quetiapine and M2 concentrations were observed. However, the predicted upper limits of the 1-sided 95% CIs did not exceed 10 msec. Therefore, QTc prolongation is unlikely to be clinically relevant at the approved dose. ClinicalTrials.gov identifiers: NCT01725282, NCT01919008, NCT01725308, NCT01737268, and NCT02362412.
Journal Article
Cardiac findings in a phase II double-blind randomized placebo-controlled trial of combination therapy (HAZDPac) to treat COVID-19 patients
2024
Hydroxychloroquine paired with Azithromycin, Vitamin C, Vitamin D, and Zinc (HAZDPac), was used as a multidrug therapy method to treat COVID-19 illness and superimposed secondary bacterial pneumonia. Concerns have been raised though about such combinations regarding cardiac QTc interval prolongation and risks of arrhythmias, which we set out to address in this study.
We evaluated cardiac safety in a Phase II Double-Blind Randomized Placebo-Controlled Trial of Combination Therapy to Treat COVID-19 Infections study, conducted by ProgenaBiome. Acutely ill patients with COVID-19 had QTc intervals recorded in an outpatient setting utilizing a continuously worn EKG monitor for the duration of the 10 days treatment. QTc intervals were normally distributed. Two-sample t-tests were used to measure any significant differences in QTc intervals between treatment and placebo groups.
Between March 2020 and June 2021, 118 COVID-19 patients were recruited and signed informed consent, of which 83 were enrolled for a Double-Blind Randomized Placebo-Controlled Trial. Of the 83, 52 patients were randomly assigned to receive HAZDPac treatment, and 31 patients to receive placebo. Overall, and in stratified analysis by gender, maximum QTc values of patients in the treatment arm were normal and no differences were observed when compared to maximum QTc values from patients in the placebo arm (p ≥ 0.15). There were no adverse events related to HAZDPac treatment.
We found that the outpatient treatment of COVID-19 patients with HAZDPac which includes Hydroxychloroquine and Azithromycin, was not associated with prolongation of QTc compared to placebo and QTc remained within normal range.
Clinical Trial NCT04482686, clinicaltrials.gov, date of registration 07/21/2020.
Journal Article
Effect of alectinib on cardiac electrophysiology: results from intensive electrocardiogram monitoring from the pivotal phase II NP28761 and NP28673 studies
by
Bogman, Katrijn
,
Morcos, Peter N.
,
Golding, Sophie
in
Algorithms
,
Bradycardia - chemically induced
,
Bradycardia - physiopathology
2017
Purpose
Alectinib, a central nervous system (CNS)-active ALK inhibitor, has demonstrated efficacy and safety in
ALK
+ non-small-cell lung cancer that has progressed following crizotinib treatment. Other ALK inhibitors have shown concentration-dependent QTc prolongation and treatment-related bradycardia. Therefore, this analysis evaluated alectinib safety in terms of electrophysiologic parameters.
Methods
Intensive triplicate centrally read electrocardiogram (ECG) and matched pharmacokinetic data were collected across two alectinib single-arm trials. Analysis of QTcF included central tendency analysis [mean changes from baseline with one-sided upper 95% confidence intervals (CIs)], categorical analyses, and relationship between change in QTcF and alectinib plasma concentrations. Alectinib effects on other ECG parameters (heart rate, PR interval and QRS duration) were also evaluated.
Results
Alectinib did not cause a clinically relevant change in QTcF. The maximum mean QTcF change from baseline was 5.3 ms observed pre-dose at week 2. The upper one-sided 95% CI was <10 ms at all time points. There was no relevant relationship between change in QTcF and alectinib plasma concentrations. Alectinib treatment resulted in a generally asymptomatic exposure-dependent decrease in mean heart rate of ~11 to 13 beats per minute at week 2. No clinically relevant effects were seen on other ECG parameters. Approximately 5% of patients reported cardiac adverse events of bradycardia or sinus bradycardia; however, these were all grade 1–2.
Conclusions
Alectinib does not prolong the QTc interval or cause changes in cardiac function to a clinically relevant extent, with the exception of a decrease in heart rate which was generally asymptomatic.
Journal Article
The Application of Root Mean Square Electrocardiography (RMS ECG) for the Detection of Acquired and Congenital Long QT Syndrome
by
Etheridge, Susan P.
,
Tristani-Firouzi, Martin
,
Allen, Nancy
in
Action potential
,
Adolescent
,
Adult
2014
Precise measurement of the QT interval is often hampered by difficulty determining the end of the low amplitude T wave. Root mean square electrocardiography (RMS ECG) provides a novel alternative measure of ventricular repolarization. Experimental data have shown that the interval between the RMS ECG QRS and T wave peaks (RTPK) closely reflects the mean ventricular action potential duration while the RMS T wave width (TW) tracks the dispersion of repolarization timing. Here, we tested the precision of RMS ECG to assess ventricular repolarization in humans in the setting of drug-induced and congenital Long QT Syndrome (LQTS).
RMS ECG signals were derived from high-resolution 24 hour Holter monitor recordings from 68 subjects after receiving placebo and moxifloxacin and from standard 12 lead ECGs obtained in 97 subjects with LQTS and 97 age- and sex-matched controls. RTPK, QTRMS and RMS TW intervals were automatically measured using custom software and compared to traditional QT measures using lead II.
All measures of repolarization were prolonged during moxifloxacin administration and in LQTS subjects, but the variance of RMS intervals was significantly smaller than traditional lead II measurements. TW was prolonged during moxifloxacin and in subjects with LQT-2, but not LQT-1 or LQT-3.
These data validate the application of RMS ECG for the detection of drug-induced and congenital LQTS. RMS ECG measurements are more precise than the current standard of care lead II measurements.
Journal Article
The sodium glucose cotransporter 2 inhibitor empagliflozin does not prolong QT interval in a thorough QT (TQT) study
2013
Background
Empagliflozin is a potent, selective sodium glucose cotransporter 2 (SGLT2) inhibitor in development as an oral antidiabetic treatment. This QT interval study assessed potential effects of empagliflozin on ventricular repolarisation and other electrocardiogram (ECG) parameters.
Methods
A randomised, placebo-controlled, single-dose, double-blind, five-period crossover study incorporating a novel double-placebo period design to reduce sample size, while maintaining full statistical power. Treatments: single empagliflozin doses of 25 mg (therapeutic) and 200 mg (supratherapeutic), matching placebo and open-label moxifloxacin 400 mg (positive control). Triplicate 12-lead ECGs of 10 second duration were recorded at baseline and during the first 24 hours after dosing. The primary endpoint was mean change from baseline (MCfB) in the population heart rate-corrected QT interval (QTcN) between 1–4 hours after dosing.
Results
Thirty volunteers (16 male, 14 female, mean [range] age: 34.5 [18–52] years) were randomised. The placebo-corrected MCfB in QTcN 1–4 hours after dosing was 0.6 (90% CI: -0.7, 1.9) ms and -0.2 (-1.4, 0.9) ms for empagliflozin 25 mg and 200 mg, respectively, below the ICH E14 defined threshold of regulatory concern 10 ms. Assay sensitivity was confirmed by a placebo-corrected MCfB in QTcN 2–4 hours post-dose of 12.4 (10.7, 14.1) ms with moxifloxacin 400 mg. Empagliflozin tolerability was good for all volunteers; 23.3% experienced adverse events (AEs) with empagliflozin and 27.6% with placebo. The most frequent AE was nasopharyngitis.
Conclusions/interpretation
Single doses of empagliflozin 25 mg and 200 mg were not associated with QTcN prolongation and were well tolerated in healthy volunteers.
Trial registration
ClinicalTrials.gov:
NCT01195675
Journal Article
Effect of veliparib (ABT-888) on cardiac repolarization in patients with advanced solid tumors: a randomized, placebo-controlled crossover study
2016
Purpose
Veliparib (ABT-888) is an orally bioavailable potent inhibitor of poly(ADP-ribose) polymerase (PARP)-1 and PARP-2. This phase 1 study evaluated the effect of veliparib on corrected QT interval using Fridericia’s formula (QTcF).
Methods
Eligible patients with advanced solid tumors received single-dose oral veliparib (200 mg or 400 mg) or placebo in a 6-sequence, 3-period crossover design. The primary endpoint was the difference in the mean baseline-adjusted QTcF between 400 mg veliparib and placebo (∆∆QTcF) at six post-dose time points. Absence of clinically relevant QTcF effect was shown if the 95 % upper confidence bound (UCB) for the mean ∆∆QTcF was <10 ms for all time points. An exposure–response analysis was also performed.
Results
Forty-seven patients were enrolled. Maximum mean ∆∆QTcF of veliparib 400 mg was 6.4 ms, with a 95 % UCB of 8.9 ms; for veliparib 200 mg, the maximum mean ∆∆QTcF was 3.6 ms, with a 95 % UCB of 6.1 ms. No patient had a QTcF value >480 ms or change from baseline in QTcF interval >30 ms. Treatment-emergent adverse events (TEAEs) were experienced by 36.2, 48.9, and 47.8 % of patients while receiving veliparib 200 mg, veliparib 400 mg, and placebo, respectively. Most common TEAEs were nausea (12.8 %) and myalgia (8.5 %) after veliparib 200 mg, nausea (8.5 %) and vomiting (8.5 %) after veliparib 400 mg, and nausea (6.5 %) after placebo.
Conclusions
Single-dose veliparib (200 mg or 400 mg) did not result in clinically significant QTc prolongation and was well tolerated in patients with advanced solid tumors.
Journal Article
A randomized, double-blind, placebo-controlled study to evaluate the effect of repeated oral doses of pazopanib on cardiac conduction in patients with solid tumors
2013
Purpose
As tyrosine kinase inhibitors have been associated with cardiotoxicity, we evaluated the effect of pazopanib, an inhibitor of vascular endothelial growth factor receptor, platelet-derived growth factor receptor, and c-Kit, on electrocardiographic parameters in patients with cancer.
Methods
This double-blind, placebo-controlled, parallel-group study randomized patients (
N
= 96) to moxifloxacin (positive control) or placebo on Day 1 followed by pazopanib or placebo 800 mg/day (fasted) on Days 2–8 and 1,600 mg (with food) on Day 9. Treatment effects were evaluated by baseline-adjusted, time-matched, serial Holter electrocardiograms.
Results
Sixty-five patients were evaluable for preplanned analyses. On Day 1, the maximum mean difference in baseline-adjusted, time-matched Fridericia-corrected QT (QTcF) interval in moxifloxacin-treated patients versus placebo was 10.6 ms (90 % confidence interval [CI]: 4.2, 17.0). The administration scheme increased plasma pazopanib concentrations approximately 1.3- to 1.4-fold versus the recommended 800 mg once-daily dose. Pazopanib caused clinically significant increases from baseline in blood pressure, an anticipated class effect, and an unexpected reduction in heart rate from baseline that correlated with pazopanib exposure. On Day 9, the maximum mean difference in baseline-adjusted, time-matched QTcF interval in pazopanib-treated patients versus placebo was 4.4 ms (90 % CI: −2.4, 11.2). Mixed-effects modeling indicated no significant concentration-dependent effect of pazopanib or its metabolites on QTcF interval.
Conclusions
Pazopanib as administered in this study achieved supratherapeutic concentrations, produced a concentration-dependent decrease in heart rate, and caused a small, concentration-independent prolongation of the QTcF interval.
Journal Article
Identifying Drug-Induced Repolarization Abnormalities from Distinct ECG Patterns in Congenital Long QT Syndrome
by
Graff, Claus
,
Struijk, Johannes J.
,
Xue, Joel Q.
in
Adverse and side effects
,
Biological and medical sciences
,
Cardiac dysrhythmias
2009
Background:
The electrocardiographic QT interval is used to identify drugs with potential harmful effects on cardiac repolarization in drug trials, but the variability of the measurement can mask drug-induced ECG changes. The use of complementary electrocardiographic indices of abnormal repolarization is therefore warranted. Most drugs associated with risk are inhibitors of the rapidly activating delayed rectifier potassium current (I
kr
). This current is also inhibited in the congenital type 2 form of the long QT syndrome (LQT2). It is therefore possible that electrocardiographic LQT2 patterns might be used to identify abnormal repolarization patterns induced by drugs.
Objective:
To develop distinct T-wave morphology parameters typical of LQT2 and investigate their use as a composite measure for identification of d,l-sotalol (sotalol)-induced changes in T-wave morphology.
Methods:
Three independent study groups were included: a group of 917 healthy subjects and a group of 30 LQT2 carriers were used for the development of T-wave morphology measures. The computerized measure for T-wave morphology (morphology combination score, MCS) was based on asymmetry, flatness and notching, which are typical ECG patterns in LQT2. Blinded to labels, the new morphology measures were tested in a third group of 39 healthy subjects receiving sotalol. Over 3 days the sotalol group received 0, 160 and 320 mg doses, respectively, and a 12-lead Holter ECG was recorded for 22.5 hours each day. Drug-induced prolongation of the heart rate corrected QT interval (QTcF) was compared with changes in the computerized measure for T-wave morphology. Effect sizes for QTcF and MCS were calculated at the time of maximum plasma concentrations and for maximum change from baseline. Accuracy for separating baseline from sotalol recordings was evaluated by area under the receiver operating characteristic curves (AUCs) using all recordings from the time immediately post-dose to maximum change.
Results:
MCS separated baseline recordings from sotalol treatment with higher accuracy than QTcF for the 160 mg dose: (AUC) 84% versus 72% and for the 320 mg dose: (AUC) 94% versus 87%, p < 0.001. At maximum serum-plasma concentrations and at maximum individual change from baseline, the effect sizes for QTcF were less than half the effect sizes for MCS, p< 0.001. Effect sizes at peak changes of the mean were up to 3-fold higher for MCS compared with QTcF, p< 0.001. In subjects receiving sotalol, T-wave morphology reached similarity to LQT2, whereas QTcF did not.
Conclusion:
Distinct ECG patterns in LQT2 carriers effectively quantified repolarization changes induced by sotalol. Further studies are needed to validate whether this measure has general validity for the identification of drug-induced disturbed repolarization.
Journal Article
Effects of remifentanil, nitroglycerin, and sevoflurane on the corrected QT and Tp-e intervals during controlled hypotensive anesthesia
2016
Controlled hypotension is a preferred method in various surgical operations, but limited data are available for the effects of drug combinations that are used to ensure the desired level of hypotension on cardiac repolarization.
Randomized, prospective, double-blinded study.
The study comprised 65 patients undergoing septorhinoplasty surgery under general anesthesia.
Group S received sevoflurane inhalation alone, group R received sevoflurane and remifentanil, and group N received sevoflurane and nitroglycerine in a way that a mean arterial pressure of 60 ± 5 mm Hg was achieved.
Electrocardiogram was performed before induction (T1), 30 minutes after induction (T2), and 5 minutes after extubation (T3). Corrected QT (QTc), QT dispersion (QTd), and corrected Tp-e (Tp-ec) intervals and Tp-e/corrected QT (Tp-e/QTc) ratio were calculated.
QTc prolongation was observed at T2 and T3 in all groups, but only QTc prolongation at T2 was statistically significant in group S (P> .05). Significant prolongation of QTd interval at T2 and T3 was observed in group S (P< .05). In all groups, Tp-ec decreased at T2. However Tp-ec decrease was not statistically significant in group S (P= .103) and group R (P= .058). Tp-e/QTc was significantly decreased on T2 in all 3 groups, and it was returned to baseline at T3 (P< .05).
The present study demonstrated that none of the 3 hypotensive anesthesia methods has an overall negative effect on Tp-e and Tp-e/QTc. Therefore, we conclude that all 3 methods can be used safely in terms of proarrhythmic risk, but increased sevoflurane consumption may require more attention due to significant prolongation of QTc and QTd.
•We studied arrhythmic tendency of three hypotensive anaesthetic methods.•Sevoflurane, remifentanil, and nitroglycerine were used to achieve hypotension.•All of the 3 methods did not increase Tpeak-to-Tend interval on ECG.•Sevoflurane dose increment caused significant QTc and QTd prolongation unlike others.•All groups have no unfavorable effect on transmural dispersion of repolarization.
Journal Article