A Randomized Thorough QT Study of Apomorphine Sublingual Film in Patients With Parkinson's Disease

A randomized thorough QT study was conducted to assess the effects of apomorphine sublingual film (SL-APO) on corrected QT interval (QTc) and other cardiac conduction parameters in patients with Parkinson's disease (PD) and "OFF" episodes. Patients were titrated to an SL-APO dose that resulted in FULL "ON," followed by up to two additional doses (maximum 60 mg), then randomized at the highest tolerated dose to a treatment sequence of SL-APO, placebo, and moxifloxacin (400 mg, positive control) in a three-way crossover design. Changes from baseline in time-matched, placebo-adjusted Fridericia-corrected QTc interval (ΔΔQTcF) and Bazett-corrected QTc interval (ΔΔQTcB) were analyzed from postdose electrocardiograms. Forty patients were randomized and received single doses of study treatments. Upper limits of 90% confidence intervals (CIs) for ΔΔQTcF of SL-APO were below the 10-millisecond regulatory threshold at all prespecified timepoints, demonstrating no clinically significant effect on QTcF. Lower limits of 90% CIs for ΔΔQTcF of moxifloxacin exceeded the 5-millisecond regulatory threshold at all timepoints up to 3 hours, confirming assay sensitivity. SL-APO had no clinically meaningful effects on QTcB, PR/QRS intervals, heart rate, or electrocardiogram-derived morphology (EudraCT identifier: 2016-001762-29; ClinicalTrials.gov identifier: NCT03187301).

Comparison of electrocardiograms (ECG) waveforms and centralized ECG measurements between a simple 6-lead mobile ECG device and a standard 12-lead ECG

Background

Interval duration measurements (IDMs) were compared between standard 12‐lead electrocardiograms (ECGs) and 6‐lead ECGs recorded with AliveCor's KardiaMobile 6L, a hand‐held mobile device designed for use by patients at home.

Methods

Electrocardiograms were recorded within, on average, 15 min from 705 patients in Mayo Clinic's Windland Smith Rice Genetic Heart Rhythm Clinic. Interpretable 12‐lead and 6‐lead recordings were available for 685 out of 705 (97%) eligible patients. The most common diagnosis was congenital long QT syndrome (LQTS, 343/685 [50%]), followed by unaffected relatives and patients (146/685 [21%]), and patients with other genetic heart diseases, including hypertrophic cardiomyopathy (36 [5.2%]), arrhythmogenic cardiomyopathy (23 [3.4%]), and idiopathic ventricular fibrillation (14 [2.0%]). IDMs were performed by a central ECG laboratory using lead II with a semi‐automated technique.

Results

Despite differences in patient position (supine for 12‐lead ECGs and sitting for 6‐lead ECGs), mean IDMs were comparable, with mean values for the 12‐lead and 6‐lead ECGs for QTcF, heart rate, PR, and QRS differing by 2.6 ms, −5.5 beats per minute, 1.0 and 1.2 ms, respectively. Despite a modest difference in heart rate, intervals were close enough to allow a detection of clinically meaningful abnormalities.

Conclusions

The 6‐lead hand‐held device is potentially useful for a clinical follow‐up of remote patients, and for a safety follow‐up of patients participating in clinical trials who cannot visit the investigational site. This technology may extend the use of 12‐lead ECG recordings during the current COVID‐19 pandemic as remote patient monitoring becomes more common in virtual or hybrid‐design clinical studies.

Artificial Intelligence-Enabled Assessment of the Heart Rate Corrected QT Interval Using a Mobile Electrocardiogram Device

BACKGROUND

Heart rate-corrected QT interval (QTc) prolongation, whether secondary to drugs, genetics including congenital long QT syndrome, and/or systemic diseases including SARS-CoV-2-mediated coronavirus disease 2019 (COVID-19), can predispose to ventricular arrhythmias and sudden cardiac death. Currently, QTc assessment and monitoring relies largely on 12-lead electrocardiography. As such, we sought to train and validate an artificial intelligence (AI)-enabled 12-lead ECG algorithm to determine the QTc, and then prospectively test this algorithm on tracings acquired from a mobile ECG (mECG) device in a population enriched for repolarization abnormalities.

METHODS

Using >1.6 million 12-lead ECGs from 538 200 patients, a deep neural network (DNN) was derived (patients for training, n = 250 767; patients for testing, n = 107 920) and validated (n = 179 513 patients) to predict the QTc using cardiologist-overread QTc values as the "gold standard". The ability of this DNN to detect clinically-relevant QTc prolongation (eg, QTc ≥500 ms) was then tested prospectively on 686 patients with genetic heart disease (50% with long QT syndrome) with QTc values obtained from both a 12-lead ECG and a prototype mECG device equivalent to the commercially-available AliveCor KardiaMobile 6L.

RESULTS

In the validation sample, strong agreement was observed between human over-read and DNN-predicted QTc values (-1.76±23.14 ms). Similarly, within the prospective, genetic heart disease-enriched dataset, the difference between DNN-predicted QTc values derived from mECG tracings and those annotated from 12-lead ECGs by a QT expert (-0.45±24.73 ms) and a commercial core ECG laboratory [10.52±25.64 ms] was nominal. When applied to mECG tracings, the DNN's ability to detect a QTc value ≥500 ms yielded an area under the curve, sensitivity, and specificity of 0.97, 80.0%, and 94.4%, respectively.

CONCLUSIONS

Using smartphone-enabled electrodes, an AI DNN can predict accurately the QTc of a standard 12-lead ECG. QTc estimation from an AI-enabled mECG device may provide a cost-effective means of screening for both acquired and congenital long QT syndrome in a variety of clinical settings where standard 12-lead electrocardiography is not accessible or cost-effective.

Assessment of the effect of erdafitinib on cardiac safety: analysis of ECGs and exposure-QTc in patients with advanced or refractory solid tumors

PURPOSE

To characterize the effect of erdafitinib on electrocardiogram (ECG) parameters and the relationship between erdafitinib plasma concentrations and QTc interval changes in patients with advanced or refractory solid tumors.

METHODS

Triplicate ECGs and continuous 12-lead Holter data were collected in the dose escalation part (Part 1) of the first-in-human study, with doses ranging from 0.5 to 12 mg. Triplicate ECG monitoring continued in Parts 2-4 where 2 dose regimens selected from Part 1 were expanded in prespecified tumor types. Analyses of ECG data included central tendency analyses, identification of categorical outliers and morphological assessment. A concentration-QTc analysis was conducted using a linear mixed-effect model based on extracted time matching Holter data.

RESULTS

Central tendency, categorical outlier, and ECG morphologic analyses from 187 patients revealed no clinically significant effect of erdafitinib on heart rate, atrioventricular conduction or cardiac depolarization (PR and QRS), and no effect on cardiac repolarization (QTc). Concentration-QTc analysis from 62 patients indicated that the slopes of relationship between total and free erdafitinib plasma concentrations and QTcI (mean exponent of 0.395) were estimated as - 0.00269 ms/(ng/mL) and - 1.138 ms/(ng/mL), respectively. The predicted change in QTcI at the observed geometric mean of total and free concentration at the highest therapeutic erdafitinib dose (9 mg daily) was < 10 ms at the upper bound of the two-sided 90% confidence interval.

CONCLUSIONS

ECG data and the concentration-QTc relationships demonstrate that erdafitinib does not prolong QTc interval and has no effects on cardiac repolarization or other ECG parameters. Clinical trial registration numbers NCT01703481, EudraCT: 2012-000697-34.

Prevention of sudden cardiac death in the young: Developing a rational, reliable, and sustainable national health care resource. A report from the Cardiac Safety Research Consortium

This White Paper, prepared by members of the Cardiac Safety Research Consortium, discusses important issues regarding sudden cardiac death in the young (SCDY), a problem that does not discriminate by gender, race, ethnicity, education, socioeconomic level, or athletic status. The occurrence of SCDY has devastating impact on families and communities. Sudden cardiac death in the young is a matter of national and international public health, and its prevention has generated deep interest from multiple stakeholders, including families who have lost children, advocacy groups, academicians, regulators, and the medical industry. To promote scientific and clinical discussion of SCDY prevention and to germinate future initiatives to move this field forward, a Cardiac Safety Research Consortium-sponsored Think Tank was held on February 21, 2015 at the US Food and Drug Administration's White Oak facilities, Silver Spring, MD. The ultimate goal of the Think Tank was to spark initiatives that lead to the development of a rational, reliable, and sustainable national health care resource focused on SCDY prevention. This article provides a detailed summary of discussions at the Think Tank and descriptions of related multistakeholder initiatives now underway: it does not represent regulatory guidance.

Benefits of Centralized ECG Reading in Clinical Oncology Studies

BACKGROUND

Many clinical trials of investigational oncologic agents utilize electrocardiogram (ECG) machine measurements of QTc, for inclusion/exclusion and dosing decisions, though their reliability in this setting has not been established.

METHODS

We compared the digital ECG machine QTc measurements with those obtained by a centralized ECG core lab on more than 270,000 consecutive ECGs collected from 299 clinical oncology trials.

RESULTS

The mean difference between the ECG machine measurements and the central measured QTcF was 1.8 ± 15.7 milliseconds. In addition, 29.7% of ECGs with an ECG machine-measured QTcF >450 milliseconds had a centrally measured QTcF <450 milliseconds, 44.6% of ECGs with an ECG machine-measured QTcF >470 milliseconds had a centrally measured QTcF <470 milliseconds, and 77.2% of ECGs with an ECG machine-measured QTcF >500 milliseconds had a centrally measured QTcF <500 milliseconds. The likelihood of a large discrepancy between the ECG machine- and centrally measured value for QTcF increased at both the high and low ends of the range of ECG machine QTcF measurements.

CONCLUSIONS

While on average ECG machine-measured QTcF values were very similar to the central core lab measurements; there were very significant discrepancies which will have important implications for patient recruitment for clinical oncology trials as well as for patient safety during dosing with new oncologic agents. Reliance on ECG machine QTc measurements during clinical oncology trials may lead to unnecessary exclusion of patients as well as unneeded treatment interruptions.

Moxifloxacin-induced QTc interval prolongations in healthy male Japanese and Caucasian volunteers: a direct comparison in a thorough QT study

AIM

We investigated whether moxifloxacin-induced QTc prolongations in Japanese and Caucasian healthy male volunteers were significantly different.

METHODS

A two period, randomized, crossover, ICH-E14-compliant thorough QT (TQT) study compared placebo-corrected changes in QTc interval from baseline (ΔΔQTc F) and concentration-effect relationships following administration of placebo and 400 mg moxifloxacin to 40 healthy male volunteers from each ethnic population. The point estimates of ΔΔQTc F for each population, and the difference between the two, were calculated at a geometric mean Cmax of moxifloxacin using a linear mixed effects model. The concentration-effect slopes of the two populations were also compared. Equivalence was concluded if the two-sided 90% confidence interval of the difference in ΔΔQTc F was contained within -5 ms to +5 ms limits and the ratio of the slopes was between 0.5 and 2.

RESULTS

There were no statistically significant differences between the two populations studied, Japanese vs. Caucasians, respectively, for moxifloxacin Cmax (3.27 ± 0.6 vs. 2.98 ± 0.7 µg ml(-1) ), ΔΔQTc F (9.63 ± 1.15 vs. 11.46 ± 1.19 ms at Cmax of 3.07 µg ml(-1) ) and concentration-response slopes (2.58 ± 0.62 vs. 2.34 ± 0.64 ms per µg ml(-1) ). The difference in the two ΔΔQTc F of -1.8 (90% CI -4.6, 0.9) and the ratio of the two slopes (1.1; 90% CI 0.63, 1.82) were within pre-specified equivalence limits.

CONCLUSIONS

Moxifloxacin-induced QTc prolongations did not differ significantly between the Japanese and Caucasian subjects. However, before our findings are more widely generalized, further studies in other populations and with other QT-prolonging drugs are needed to clarify whether inter-ethnic differences in QT sensitivity exist and whether ethnicity of the study population may affect the outcome of a TQT study.

The evaluation and management of drug effects on cardiac conduction (PR and QRS intervals) in clinical development

Recent advances in electrocardiographic monitoring and waveform analysis have significantly improved the ability to detect drug-induced changes in cardiac repolarization manifested as changes in the QT/corrected QT interval. These advances have also improved the ability to detect drug-induced changes in cardiac conduction. This White Paper summarizes current opinion, reached by consensus among experts at the Cardiac Safety Research Consortium, on the assessment of electrocardiogram-based safety measurements of the PR and QRS intervals, representing atrioventricular and ventricular conduction, respectively, during drug development.

Caltha palustris L. Seed Oil. A source of four fatty acids withcis-5-unsaturation

The seed oil ofCaltha palustris L. yields two unusual polyunsaturated components, all-cis-5,11,14-eicosatrienoic acid (23%) and all-cis-5,11,14,17-eicosatetraenoic acid (1%). The C(18) monoene fraction (26%) is a mixture ofcis-5- andcis-9-octadecenoic acids (2ratio1). The C(20) monoene fraction (12%) is a mixture ofcis-11- andcis-5-isomers (3ratio1).

(S)-1,2-diacyl-3-acetins: Optically active triglycerides fromEuonymus verrucosus seed oil

The seed oil ofEuonymus verrucosus Scop., family Celastraceae, contains more than 90% 1,2-diacyl-3-acetins (monoacetotriglycerides). The constituent triglyceride acids, other than acetic, are the usual long-chain fatty acids.Thin-layer chromatography (TLC), infrared (IR) and hydrolysis with pancreatic lipase indicate that the acetic acid is esterified exclusively on the outer glycerol carbon atoms. The isolated mixed monoacetotriglycerides exhibit optical rotation caused by asymmetry of the central glycerol carbon atom. Comparison with synthetic products of known configuration shows that the natural material is essentially all (S)-1,2-diacyl-3-acetin.IR, TLC and GLC analyses indicate the presence of monoacetotriglycerides in seven other species of Celastraceae and five species in three other plant families in amounts from 13 to 98%.

Evaluation of ventricular arrhythmias in early clinical pharmacology trials and potential consequences for later development

This white paper, prepared by members of the Cardiac Safety Research Consortium, discusses several important issues regarding the evaluation of ventricular arrhythmias in early clinical pharmacology trials and their potential consequences for later clinical drug development. Ventricular arrhythmias are infrequent but potentially important medical events whose occurrence in early clinical pharmacology trials can dramatically increase safety concerns. Given the increasing concern with all potential safety signals and the resultant more extensive electrocardiographic monitoring of subjects participating in early phase trials, an important question must be addressed: Are relatively more frequent observations of ventricular arrhythmias related simply to more extensive monitoring, or are they genuinely related to the drug under development? The discussions in this paper provide current thinking and suggestions for addressing this question.

Drug-induced cardiac toxicity: emphasizing the role of electrocardiography in clinical research and drug development

This review describes the role of electrocardiography in clinical research and drug development, and addresses its utility in defining cardiac toxicity from noncardiac investigational drugs. Principles for designing electrocardiographic monitoring for cardiac safety in clinical trials are also reviewed.

Development of subcellular mRNA compartmentation in hippocampal neurons in culture

Neurons possess an RNA transport system that is present in dendrites (but not axons) and sort mRNAs so that some mRNAs are restricted to cell bodies while a few others (like the mRNA for MAP2) are present in dendrites. The present study evaluates when dendrite-specific RNA transport and mRNA sorting into cell body and somatodendritic compartments first appear in developing hippocampal neurons maintained in culture. A 3H-uridine pulse-chase paradigm was used to evaluate transport of newly synthesized RNA from the site of synthesis in the nucleus into the developing neurites. The intracellular distribution of mRNAs encoding actin, tubulin, GAP-43, and MAP2 as well as polyA RNA and rRNA was evaluated by in situ hybridization at different stages of development. Newly synthesized RNA was translocated into both developing axons and dendrites early in development, but only into dendrites as the neurons matured. Tubulin, GAP-43, and actin mRNAs, which are restricted to cell bodies in mature neurons, were found exclusively in neuronal cell bodies at all developmental stages. MAP2 mRNA, which is present in the dendrites of mature neurons, was present at very low levels in neurons at 2 or 3 d in culture and was not detectable within dendrites. The overall levels of MAP2 mRNA increased over time, and by 5-7 d in culture, MAP2 mRNA was detectable in some dendrites. PolyA RNA and rRNA were detectable in developing neurites including axons. Levels of polyA and rRNA increased in dendrites as neurons matured while labeling of axons diminished. By 10 d in culture, axonal labeling for polyA and rRNA had virtually disappeared. The increase in the levels of polyA, rRNA, and MAP2 mRNA in dendrites between 5 and 7 d in culture corresponds roughly with the appearance of other dendritic characteristics and the beginning of dendritic outgrowth.

Subcellular distribution of rRNA and poly(A) RNA in hippocampal neurons in culture

In situ hybridization was used to assess the subcellular distribution of rRNA and poly(A) RNA in hippocampal neurons maintained in culture. Labeling produced with 35S-labeled probes to either rRNA or poly(A) was heaviest over the cell body with lighter, patchy labeling of proximal dendrites. In contrast, 3H-labeled probes labeled dendrites throughout their length, and the ratio of dendritic to cell body labeling was higher with 3H-labeled probes. There was no detectable labeling of axons of mature neurons with either probe. The pattern of hybridization produced by 35S-labeled oligonucleotide probes to rRNA varied depending on the concentration of the oligonucleotide. These studies provide the first detailed study of the subcellular distribution of rRNA and poly(A) RNA in neurons, and highlight technical issues to consider when evaluating results of hybridizations carried out with 35S- and 3H-labeled probes on cells in culture.

Inhibition of protein synthesis alters the subcellular distribution of mRNA in neurons but does not prevent dendritic transport of RNA

This study evaluates whether protein synthesis plays a role in targeting RNA molecules to different subcellular domains within neurons. Transport of newly synthesized RNA (labeled with [3H]uridine) was examined in the presence of the protein synthesis inhibitors puromycin and cycloheximide. In situ hybridization was used to determine whether inhibition of protein synthesis altered the subcellular distribution of mRNAs. Transport of recently synthesized RNA was not disrupted after prolonged exposure to either inhibitor. However, inhibition of protein synthesis caused several mRNAs that are normally confined to the cell body to appear in dendrites. The distribution of mRNAs that are normally present in dendrites was unaffected. These findings suggest that protein synthesis is not required to translocate RNA into the dendrites but may play a role in restricting particular mRNAs to the neuronal cell body.

Temperature-dependent blockade of nucleocytoplasmic transport of newly synthesized RNA in neurons

This study evaluates the temperature sensitivity of transport of recently synthesized RNA from the nucleus to the cytoplasm (nucleocytoplasmic transport) in CNS neurons. Rat hippocampal slices were incubated with [3H]uridine for 1 h to label recently synthesized RNA. Slices were then fixed immediately or maintained at 27 degrees C or 37 degrees C for chase intervals of 3, 4.5, and 6 h to allow for nucleocytoplasmic transport of recently synthesized RNA. The time-dependent translocation of recently synthesized RNA was evaluated autoradiographically. At the end of the 1 h pulse at either 27 degrees C or 37 degrees C, the label was localized exclusively over nuclei. In slices maintained at 37 degrees C, labeling expanded to cover the cell body and proximal dendrites. However, in slices that were labeled and maintained at room temperature, labeling remained confined to the nucleus. In slices that were pulse-labeled at room temperature, and then transferred to 37 degrees C medium, cytoplasmic labeling increased as a function of time. Nucleocytoplasmic transport of RNA in cultured rat hippocampal neurons showed a comparable temperature sensitivity. The inhibition of nucleocytoplasmic transport of RNA at room temperature provides an opportunity to evaluate neuronal function when no new RNA molecules can reach the cytoplasm.

The effect of prospective payment under DRGs on the market value of hospitals

This article investigates the effect of a change in Medicare payment regulations on for-profit hospital market values. A theoretical argument on the effects of this regulatory event is presented in which hospital managers are concerned about firm wealth but also value prestige, provider perceptions of quality, and perhaps other prerequisites. In this case, DRGs will induce hospitals to seek higher wealth because they increase the opportunity cost of nonpecuniary benefits. The issue is pursued empirically by estimating the market response to DRG legislation using seemingly unrelated regressions.

Differential subcellular localization of particular mRNAs in hippocampal neurons in culture

In situ hybridization was used to assess the subcellular distribution of mRNAs encoding several important neuronal proteins in hippocampal neurons in culture. mRNA encoding GAP-43, a protein that is largely excluded from dendrites, was restricted to nerve cell bodies, as were mRNAs encoding neurofilament-68 and beta-tubulin, which are prominent constituents of dendrites and of axons. In contrast, mRNA encoding MAP-2, a protein that is selectively distributed in dendrites and cell bodies, was present in both dendrites and cell bodies. These results demonstrate that different mRNAs are differentially distributed within individual hippocampal neurons. Taken together with previous findings from other laboratories, our results suggest that only a limited set of mRNAs are available for local translation within dendrites.

Degradation of linoleic acid hydroperoxides by a cysteine . FeCl3 catalyst as a model for similar biochemical reactions. II. Specificity in formation of fatty acid epoxides

1. The degradation of linoleic acid hydroperoxide by cysteine and FeCl3 resulted in formation of a number of oxygenated fatty acids, among which isomeric epoxyoxooctadecenoic and epoxyhydroxyoctadecenoic acids were major products. Pure isomeric hydroperoxides, either 13-L(S)-hydroperoxy-cis-9,trans-11-octadecadienoic acid or 9-D(S)-hydroperoxy-trans-10,cis-12-octadecadienoic acid, were transformed into either 12,13-epoxides or 9,10-epoxides, respectively. 2. From 13-L(S)-hydroperoxy-cis-9,trans-11-octadecadienoic acid, the epoxides were identified as trans-12,13-epoxy-9-oxo-trans-10-octadecenoic acid, trans-12,13-epoxy-9-hydroxy-trans-10-octadecenoic acid, cis-12,13-epoxy-9-oxo-trans-10-octadecenoic acid, trans-12,13-epoxy-erythro-11-hydroxy-cis(trans)-9-octadecenoic acid and trans-12,13-epoxy-threo-11-hydroxy-cis(trans)-9-octadecenoic acid. 3. The 12,13-epoxides were found to be optically active, indicating that the chiral center of the 13-L(S)-hydroperoxy carbon was retained. 4. Although many epoxy fatty acids previously have been identified as linoleic acid hydroperoxide products, this study reports a more complete structural analysis of the various epoxides and allows an assessment of the mechanisms of their formation from hydroperoxides.

Cyclopropene fatty acids of selected seed oils from bombacaceae, malvaceae, and sterculiaceae

Fatty acid compositions of seed oils from three species of Bombacaceae, eleven from Malvaceae, and six from Sterculiaceae were determined. Each of the seed oils contains varying amounts of both malvalic and sterculic acids accompanied by one or both of the corresponding cyclopropane fatty acids. In addition, the seed oil of Pachira aquatic Aubl. (Bombacaceae) contains 12.8% alpha-hydroxysterculic acid.