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1.
Clin Infect Dis ; 73(11): e3949-e3955, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-33165503

RESUMO

BACKGROUND: We evaluated an inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine for immunogenicity and safety in adults aged 18-59 years. METHODS: In this randomized, double-blinded, controlled trial, healthy adults received a medium dose (MD) or a high dose (HD) of the vaccine at an interval of either 14 days or 28 days. Neutralizing antibody (NAb) and anti-S and anti-N antibodies were detected at different times, and adverse reactions were monitored for 28 days after full immunization. RESULTS: A total of 742 adults were enrolled in the immunogenicity and safety analysis. Among subjects in the 0, 14 procedure, the seroconversion rates of NAb in MD and HD groups were 89% and 96% with geometric mean titers (GMTs) of 23 and 30, respectively, at day 14 and 92% and 96% with GMTs of 19 and 21, respectively, at day 28 after immunization. Anti-S antibodies had GMTs of 1883 and 2370 in the MD group and 2295 and 2432 in the HD group. Anti-N antibodies had GMTs of 387 and 434 in the MD group and 342 and 380 in the HD group. Among subjects in the 0, 28 procedure, seroconversion rates for NAb at both doses were both 95% with GMTs of 19 at day 28 after immunization. Anti-S antibodies had GMTs of 937 and 929 for the MD and HD groups, and anti-N antibodies had GMTs of 570 and 494 for the MD and HD groups, respectively. No serious adverse events were observed during the study period. CONCLUSIONS: Adults vaccinated with inactivated SARS-CoV-2 vaccine had NAb as well as anti-S/N antibody and had a low rate of adverse reactions. CLINICAL TRIALS REGISTRATION: NCT04412538.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Anticorpos Neutralizantes , Anticorpos Antivirais , Vacinas contra COVID-19 , Método Duplo-Cego , Humanos , Imunogenicidade da Vacina
2.
Artigo em Inglês | MEDLINE | ID: mdl-28223381

RESUMO

Gepotidacin is a novel, first-in-class triazaacenaphthylene antibiotic in development for treatment of conventional and biothreat infections. This was a single-dose, crossover thorough QT study in healthy subjects who were administered intravenous (i.v.) gepotidacin as a therapeutic (1,000-mg) dose and supratherapeutic (1,800-mg) dose, placebo, and 400 mg oral moxifloxacin in 4 separate treatment periods. Gepotidacin caused a mild effect on heart rate, with a largest placebo-corrected change-from-baseline heart rate of 7 and 10 beats per minute at the end of the 1,000-mg and 1,800-mg infusion, respectively. Gepotidacin caused an increase of change-from-baseline QTcF (ΔQTcF), with a peak effect at the end of infusion. The largest mean placebo-corrected ΔQTcF (ΔΔQTcF) was 12.1 ms (90% confidence interval [CI], 9.5 to 14.8) and 22.2 ms (90% CI, 19.6 to 24.9) after 1,000 mg and 1,800 mg, respectively. ΔΔQTcF rapidly fell after the end of the infusion, with a mean ΔΔQTcF of 6.1 ms 60 min after the 1,800-mg dose. Exposure-response analysis demonstrated a statistically significant positive relationship between gepotidacin plasma levels and ΔΔQTcF, with a slope of 1.45 ms per µg/ml (90% CI, 1.30 to 1.61). Using this model, the effect on ΔΔQTcF can be predicted to be 11 and 20 ms at the observed mean peak plasma concentration after the infusion of gepotidacin at 1,000 mg (7 µg/ml) and 1,800 mg (13 µg/ml), respectively. In conclusion, gepotidacin caused QT prolongation in this thorough QT study, and a mean effect can be predicted to less than 15 ms at the highest expected plasma concentration, 9 µg/ml. (This study has been registered at ClinicalTrials.gov under identifier NCT02257398.).


Assuntos
Acenaftenos/farmacologia , Antibacterianos/farmacologia , Fluoroquinolonas/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Compostos Heterocíclicos com 3 Anéis/farmacologia , Síndrome do QT Longo/induzido quimicamente , Acenaftenos/efeitos adversos , Acenaftenos/sangue , Adolescente , Adulto , Antibacterianos/efeitos adversos , Compostos Aza/farmacologia , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Eletrocardiografia/efeitos dos fármacos , Feminino , Fluoroquinolonas/efeitos adversos , Voluntários Saudáveis , Compostos Heterocíclicos com 3 Anéis/efeitos adversos , Compostos Heterocíclicos com 3 Anéis/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Moxifloxacina , Adulto Jovem
3.
J Clin Pharmacol ; 57(1): 96-104, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27338807

RESUMO

Lemborexant is a novel dual orexin receptor antagonist being developed to treat insomnia. Its potential to cause QT prolongation was evaluated using plasma concentration-response (CR) modeling applied to data from 2 multiple ascending-dose (MAD) studies. In the primary MAD study, placebo or lemborexant (2.5 to 75 mg) was administered for 14 consecutive nights. In another MAD study designed to "bridge" pharmacokinetic and safety data between Japanese and non-Japanese subjects (J-MAD), placebo or lemborexant (2.5, 10, or 25 mg) was administered for 14 consecutive nights. QT intervals were estimated using a high-precision measurement technique and evaluated using a linear mixed-effects CR model, for each study separately and for the pooled data set. When each study was analyzed separately, the slopes of the CR relationship were shallow and not statistically significant. In the pooled analysis, the slope of the CR relationship was -0.00002 milliseconds per ng/mL (90%CI, -0.01019 to 0.01014 milliseconds). The highest observed Cmax was 400 ng/mL, representing a margin 8-fold above exposures expected for the highest planned clinical dose. The model-predicted QTc effect at 400 ng/mL was 1.1 milliseconds (90%CI, -3.49 to 5.78 milliseconds). In neither the J-MAD study nor the pooled analysis was an effect of race identified. CR modeling of data from early-phase clinical studies, including plasma levels far exceeding those anticipated clinically, indicated that a QT effect >10 milliseconds could be excluded. Regulatory agreement with this methodology demonstrates the effectiveness of a CR modeling approach as an alternative to thorough QT studies.


Assuntos
Descoberta de Drogas/métodos , Eletrocardiografia/efeitos dos fármacos , Síndrome do QT Longo/induzido quimicamente , Modelos Biológicos , Antagonistas dos Receptores de Orexina/administração & dosagem , Antagonistas dos Receptores de Orexina/efeitos adversos , Adulto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Eletrocardiografia/métodos , Feminino , Humanos , Síndrome do QT Longo/diagnóstico , Síndrome do QT Longo/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
4.
J Antimicrob Chemother ; 72(2): 515-521, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27798210

RESUMO

BACKGROUND: Macrolide antibiotics may cause QT prolongation. OBJECTIVES: To study the QT effect of a novel macrolide, solithromycin. METHODS: This was a thorough QT study with a three-way crossover design performed in healthy male and female subjects to evaluate the ECG effects of a novel macrolide, solithromycin. Forty-eight subjects were randomized to receive 800 mg of intravenous (iv) solithromycin, 400 mg of oral moxifloxacin and placebo in three separate treatment periods. Continuous 12 lead ECGs were recorded at a pre-dose baseline and serially after drug administration for 24 h. RESULTS: After the 40 min infusion of 800 mg of solithromycin, the geometric mean solithromycin peak plasma concentration (Cmax) reached 5.9 (SD: 1.30) µg/mL. Solithromycin infusion caused a heart rate increase with a peak effect of 15 bpm immediately after the end of the infusion. The change-from-baseline QTcF (ΔQTcF) was similar after dosing with solithromycin and placebo and the resulting placebo-corrected ΔQTcF (ΔΔQTcF) for solithromycin was therefore small at all timepoints with a peak effect at 4 h of only 2.8 ms (upper bound of the 90% CI: 4.9 ms). Using a linear exposure-response model, a statistically significant, slightly negative slope of -0.86 ms per ng/mL (90% CI: -1.19 to -0.53; P = 0.0001) was observed with solithromycin. The study's ability to detect small QT changes was confirmed by the moxifloxacin response. Solithromycin did not have a clinically meaningful effect on the PR or QRS interval. CONCLUSIONS: The study demonstrated that solithromycin, unlike other macrolide antibiotics, does not cause QT prolongation.


Assuntos
Arritmias Cardíacas/induzido quimicamente , Sistema de Condução Cardíaco/efeitos dos fármacos , Macrolídeos/efeitos adversos , Triazóis/efeitos adversos , Estudos Cross-Over , Eletrocardiografia , Feminino , Fluoroquinolonas/uso terapêutico , Voluntários Saudáveis , Humanos , Macrolídeos/sangue , Macrolídeos/uso terapêutico , Masculino , Moxifloxacina , Placebos/administração & dosagem , Triazóis/sangue , Triazóis/uso terapêutico
5.
J Clin Pharmacol ; 57(1): 85-95, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27271102

RESUMO

The revised ICH E14 document allows the use of exposure-response analysis to exclude a small QT effect of a drug. If plasma concentrations exceeding clinically relevant levels is achieved, a positive control is not required. In cases when this cannot be achieved, there may be a need for metrics to protect against false-negative results. The objectives of this study were to create bias in electrocardiogram laboratory QT-interval measurements and define a metric that can be used to detect bias severe enough to cause false-negative results using exposure-response analysis. Data from the IQ-CSRC study, which evaluated the QT effect of 5 QT-prolonging drugs, were used. Negative bias using 3 deterministic and 2 random methods was introduced into the reported QTc values and compared with fully automated data from the underlying electrocardiogram algorithm (COMPAS). The slope estimate of the Bland-Altman plot was used as a bias metric. With the deterministic bias methods, negative bias, measured between electrocardiogram laboratory values and COMPAS, had to be larger than approximately -20 milliseconds over a QTcF range of 100 milliseconds to cause failures to predict the QT effect of ondansetron, quinine, dolasetron, moxifloxacin, and dofetilide. With the random methods, the rate of false-negatives was ≤5% with bias severity < -10 milliseconds for all 5 drugs when plasma levels exceeded those of interest. Severe and therefore detectable bias has to be introduced into reported QTc values to cause false-negative predictions with exposure-response analysis.


Assuntos
Cardiotoxinas/efeitos adversos , Eletrocardiografia/efeitos dos fármacos , Síndrome do QT Longo/induzido quimicamente , Síndrome do QT Longo/diagnóstico , Cardiotoxinas/administração & dosagem , Relação Dose-Resposta a Droga , Eletrocardiografia/métodos , Sistema de Condução Cardíaco/efeitos dos fármacos , Sistema de Condução Cardíaco/fisiopatologia , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Humanos , Síndrome do QT Longo/fisiopatologia
6.
Clin Pharmacol Drug Dev ; 5(6): 460-468, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27870477

RESUMO

Ibogaine is a psychoactive substance that may reduce opioid withdrawal symptoms. This was the first clinical trial of noribogaine, ibogaine's active metabolite, in patients established on methadone opioid substitution therapy (OST). In this randomized, double-blind, placebo-controlled single ascending-dose study, we evaluated the safety, tolerability, and pharmacokinetics of noribogaine in 27 patients seeking to discontinue methadone OST who had been switched to morphine during the previous week. Noribogaine doses were 60, 120, or 180 mg (n = 6/dose level) or matching placebo (n = 3/dose level). Noribogaine was well tolerated. The most frequent treatment-emergent adverse events were noneuphoric changes in light perception ∼1 hour postdose, headache, and nausea. Noribogaine had dose-linear increases for AUC and Cmax and was slowly eliminated (mean t1/2 range, 24-30 hours). There was a concentration-dependent increase in QTcI (0.17 ms/ng/mL), with the largest observed mean effect of ∼16, 28, and 42 milliseconds in the 60-, 120-, and 180-mg groups, respectively. Noribogaine showed a nonstatistically significant trend toward decreased total score in opioid withdrawal ratings, most notably at the 120-mg dose; however, the study design may have confounded evaluations of time to resumption of OST. Future exposure-controlled multiple-dose noribogaine studies are planned that will address these safety and design issues.


Assuntos
Ibogaína/análogos & derivados , Adulto , Área Sob a Curva , Relação Dose-Resposta a Droga , Método Duplo-Cego , Eletrocardiografia/efeitos dos fármacos , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Ibogaína/administração & dosagem , Ibogaína/efeitos adversos , Ibogaína/farmacocinética , Síndrome do QT Longo/induzido quimicamente , Síndrome do QT Longo/fisiopatologia , Masculino , Metadona , Entorpecentes , Tratamento de Substituição de Opiáceos , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Síndrome de Abstinência a Substâncias/tratamento farmacológico
7.
Food Chem Toxicol ; 91: 217-24, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26747976

RESUMO

Enzymatically-synthesized (2R,4R)-monatin has, due to its pure sweet taste, been evaluated for potential use in foods. Non-clinical studies have shown that (2R,4R)-monatin is well tolerated at high dietary concentrations, is not genotoxic/mutagenic, carcinogenic, or overtly toxic. In a pharmacokinetic and metabolism study involving 12 healthy males, consumption of a single oral dose (2 mg/kg) of (2R,4R)-monatin resulted in a small reduction of heart rate and prolongation of the QTcF interval of 20-24 ms, corresponding to the time of peak plasma levels (t(max)). These findings were evaluated in a cross-over thorough QT/QTc study with single doses of 150 mg (2R,4R)-monatin, placebo and positive control (moxifloxacin) in 56 healthy males. Peak (2R,4R)-monatin plasma concentration (1720 ± 538 ng/mL) was reached at 3.1 h (mean tmax). The placebo-corrected, change-from-baseline QTcF (ΔΔQTcF) reached 25 ms three hours after dosing, with ΔΔQTcF of 23 ms at two and four hours. Using exposure response (QTc) analysis, a significant slope of the relationship between (2R,4R)-monatin plasma levels and ΔΔQTcF was demonstrated with a predicted mean QT effect of 0.016 ms per ng/mL. While similarly high plasma levels are unlikely to be achieved by consumption of (2R,4R)-monatin in foods, QTc prolongation at this level is a significant finding.


Assuntos
Acanthaceae/química , Ácido Glutâmico/análogos & derivados , Frequência Cardíaca/efeitos dos fármacos , Indóis/farmacologia , Casca de Planta/química , Eletrocardiografia , Feminino , Ácido Glutâmico/farmacologia , Humanos , Isomerismo , Masculino
8.
Clin Ther ; 38(2): 315-26, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26749217

RESUMO

PURPOSE: A thorough QT study was conducted in healthy subjects to evaluate the effect of buprenorphine hydrochloride administered through a buccal soluble film under coverage of naltrexone to block confounding, secondary QT effects. METHODS: Healthy subjects were enrolled in a randomized, partially blinded, 4-way crossover designed study. Subjects received buprenorphine 3 mg with naltrexone, naltrexone alone (with placebo films), placebo (placebo films and placebo naltrexone), and open-label moxifloxacin 400 mg with placebo naltrexone in separate in-house treatment periods. Naltrexone treatment (50 mg) was initiated 12 hours before buprenorphine and was given every 12 hours for a total of 4 doses. ECG data were extracted from a continuous recording predose and serially after dosing on the treatment day. ECG intervals were measured at a central ECG laboratory by using the high-precision QT technique. The QT interval was corrected for heart rate with Fridericia's formula (QTcF), and change-from-predose baseline QTcF (∆QTcF) was analyzed by using a mixed effect model. FINDINGS: Fifty-eight subjects (35 males) with a mean age of 32 were enrolled into the study. Treatment with buprenorphine 3 mg resulted in a small QT effect with the largest mean naltrexone-corrected ∆QTcF reaching 5.8 msec at 8 hours' postdosing (upper bound of the 90% CI below 10 msec). Exposure response analysis with a linear model demonstrated a significant linear relationship between plasma levels and naltrexone-corrected ∆QTcF, with an estimated mean slope of 0.65 msec per nanogram/milliliter (90% CI, 0.22 to 1.08). Using the exposure response model, an effect on ∆QTcF of 4.5 msec (2.80 to 6.12) can be predicted at the observed geometric peak plasma level after administration of the 3-mg buprenorphine dose in this study (3.6 ng/mL [3.33 to 3.98]). Naltrexone alone did not have a relevant effect on the QTcF interval. IMPLICATIONS: The present study showed that buprenorphine plasma levels up to 5 ng/mL had no effect on the QTc above the level of clinical concern.


Assuntos
Buprenorfina/farmacologia , Fluoroquinolonas/farmacologia , Naltrexona/farmacologia , Adulto , Estudos Cross-Over , Método Duplo-Cego , Eletrocardiografia/efeitos dos fármacos , Feminino , Coração/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Moxifloxacina
9.
J Clin Pharmacol ; 55(9): 1051-60, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25855155

RESUMO

This randomized, double-blind, placebo-controlled, 6-arm, parallel-design study investigated cardiac and hematological pharmacodynamic effects of ceralifimod (ONO-4641), a selective sphingosine-1-phosphate (S1P) receptor modulator, over a broad dose range in direct comparison with the nonselective S1P modulator fingolimod. Healthy subjects were assigned to ceralifimod (0.01, 0.025, 0.05, or 0.10 mg), fingolimod (0.5 mg), or placebo once daily for 14 days (n = 24 per group). After 14 days of treatment, mean absolute lymphocyte count percentage change from baseline was greatest in the fingolimod (-62%) and ceralifimod 0.10 mg (-56%) groups. On treatment cessation, lymphocyte recovery was faster in the ceralifimod versus the fingolimod group. Ceralifimod showed dose- and concentration-dependent chronotropic effect. Cardiac effects in the fingolimod group were dependent on fingolimod-P concentrations. Maximum mean heart rate (HR) effect on day 1 was larger with fingolimod (placebo-adjusted change from time-matched baseline HR [ΔΔHR], -14.9 beats per minute [bpm]) versus ceralifimod (ΔΔHR, -6.2 and -12.0 bpm for the 0.05- and 0.10-mg doses, respectively). Ceralifimod's effect on the PR interval was minor. Safety biomarker results suggest that potential therapeutic doses of ceralifimod, in particular the 0.05-mg dose, might result in reduced occurrence of bradycardia, atrioventricular block absolute lymphocyte count and grade 3/4 lymphopenia compared with fingolimod 0.5 mg.


Assuntos
Azetidinas/farmacocinética , Cloridrato de Fingolimode/farmacocinética , Coração/efeitos dos fármacos , Imunossupressores/farmacocinética , Linfócitos/efeitos dos fármacos , Naftalenos/farmacocinética , Adolescente , Adulto , Área Sob a Curva , Azetidinas/administração & dosagem , Azetidinas/sangue , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Cloridrato de Fingolimode/administração & dosagem , Cloridrato de Fingolimode/sangue , Meia-Vida , Humanos , Imunossupressores/administração & dosagem , Imunossupressores/sangue , Masculino , Pessoa de Meia-Idade , Naftalenos/administração & dosagem , Naftalenos/sangue , Adulto Jovem
10.
Int J Antimicrob Agents ; 45(4): 393-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25681068

RESUMO

Two hundred healthy subjects were enrolled in a randomised, partially double-blinded, single-centre, parallel design thorough QT study to demonstrate that dalbavancin had no clinical effect on the 12-lead ECG QTc. Fifty patients in each group received either dalbavancin 1000 mg intravenous (i.v.), dalbavancin 1500 mg i.v. or placebo i.v., each infused over 30 min, or 400 mg oral moxifloxacin. Ten replicate 12-lead ECGs were extracted at pre-defined time points before and up to 24 h post dosing and at corresponding time points during baseline. Dalbavancin did not have an effect on the QTcF interval, and an effect exceeding 10 ms could be excluded at all time points after a single i.v. dose of 1000 mg and 1500 mg. The largest placebo-corrected change-from-baseline QTcF (ΔΔQTcF) was 1.5 ms in the 1000 mg dalbavancin group at 6 h and 0.2 ms in the 1500 mg group at 24 h. A small concentration-dependent effect of dalbavancin on ΔΔQTcF was identified with an estimated negative population slope of -0.0051 ms per µg/mL. Assay sensitivity was demonstrated by the effect of 400 mg moxifloxacin, which peaked at 2 h at ΔΔQTcF of 12.9 ms, with the lower bound of the 90% CI of the effect exceeding 5 ms at all three pre-defined time points. Dalbavancin did not exert a relevant effect on heart rate or PR or QRS intervals. Dalbavancin in i.v. doses up to 1500 mg did not prolong the QTc interval and had no effect on heart rate or PR and QRS intervals.


Assuntos
Antibacterianos/efeitos adversos , Sistema de Condução Cardíaco/efeitos dos fármacos , Sistema de Condução Cardíaco/fisiologia , Dermatopatias Bacterianas/tratamento farmacológico , Teicoplanina/análogos & derivados , Administração Intravenosa , Adolescente , Adulto , Antibacterianos/administração & dosagem , Método Duplo-Cego , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placebos/administração & dosagem , Teicoplanina/administração & dosagem , Teicoplanina/efeitos adversos , Adulto Jovem
11.
Drug Des Devel Ther ; 9: 175-85, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25552906

RESUMO

The effects of selexipag and its active metabolite ACT-333679 on cardiac repolarization were assessed in a thorough QT study as per International Conference on Harmonisation E14 guidance. In this randomized, double-blind, placebo/positive-controlled, parallel-group study, healthy male and female subjects were randomized to receive escalating doses of selexipag (n=91) or placebo/moxifloxacin (n=68). Ascending multiple doses of selexipag in the range of 400-1,600 µg or placebo were administered twice daily for 21 days. Following a nested crossover design, subjects in the moxifloxacin/placebo treatment group received a single oral 400 mg dose of moxifloxacin on day 2 or 24. The primary endpoint (QT interval correction using individualized formula [QTcI]) was chosen based on a prospectively defined test applied to on-treatment data. The mean baseline-adjusted placebo-corrected ΔQTcI (ΔΔQTcI) for selexipag was small at all time points and never exceeded 1.4 msec (upper bound of 90% confidence interval [CI], 3.9 msec) on 800 µg or -0.7 msec (upper bound of 90% CI, 2.1 msec) on 1,600 µg. The mean ΔΔQTcI peak effect for moxifloxacin was 7.5 msec (lower bound of 90% CI, 4.8 msec). The exposure-response analysis did not demonstrate a relevant relationship between plasma concentrations of selexipag or ACT-333679 and ΔΔQTcI but, in contrast, a positive slope within the expected range for moxifloxacin. In conclusion, selexipag does not have an effect on cardiac repolarization.


Assuntos
Acetamidas/administração & dosagem , Acetamidas/farmacologia , Síndrome do QT Longo , Pirazinas/administração & dosagem , Pirazinas/farmacologia , Receptores de Prostaglandina/agonistas , Acetamidas/efeitos adversos , Acetamidas/química , Administração Oral , Adolescente , Adulto , Método Duplo-Cego , Eletrocardiografia , Feminino , Fluoroquinolonas/administração & dosagem , Fluoroquinolonas/química , Fluoroquinolonas/farmacologia , Humanos , Síndrome do QT Longo/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Moxifloxacina , Placebos , Pirazinas/efeitos adversos , Pirazinas/química , Receptores de Epoprostenol , Adulto Jovem
12.
Basic Clin Pharmacol Toxicol ; 116(5): 429-37, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25287214

RESUMO

Ponesimod is an orally active selective sphingosine-1-phosphate receptor 1 modulator under investigation for the treatment of multiple sclerosis. This was a single-centre, double-blind, randomized, placebo- and positive-controlled parallel-group study investigating the effects of ponesimod on the QTc interval in healthy individuals. A nested cross-over comparison between moxifloxacin and placebo was included in the combined moxifloxacin/placebo treatment group. Subjects in group A received multiple doses of 10-100 mg ponesimod according to an uptitration regimen on days 2-23 and moxifloxacin-matching placebo on days 1 and 24. Subjects in group B received ponesimod-matching placebo on days 2-23 and were randomized to receive either a single dose of 400 mg moxifloxacin or matching placebo on days 1 and 24. The primary end-point was the baseline-adjusted, placebo-corrected effect on the individually corrected QT interval (QTcI) on days 12 (after 5 days of 40 mg ponesimod) and 23 (after 5 days of 100 mg ponesimod). Ponesimod caused a mild QTcI prolongation with a largest effect of 6.9 ms (90% two-sided confidence interval (CI): 2.5-11.3) and 9.1 ms (90% CI: 4.1-14.0) for doses of 40 mg and 100 mg, respectively. A concentration-effect analysis confirmed the QTcI-prolonging effect of ponesimod with a shallow slope of 0.0053 ms per ng/mL. Using the concentration-effect analysis, the QTc prolongation caused by 20 mg ponesimod and the current highest therapeutic dose was predicted to be below the level of clinical concern (i.e. an upper bound of the two-sided 90% CI of ≥10 ms).


Assuntos
Sistema de Condução Cardíaco/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Síndrome do QT Longo/induzido quimicamente , Receptores de Lisoesfingolipídeo/efeitos dos fármacos , Tiazóis/efeitos adversos , Potenciais de Ação , Adolescente , Adulto , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Esquema de Medicação , Eletrocardiografia , Feminino , Fluoroquinolonas/efeitos adversos , Voluntários Saudáveis , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Síndrome do QT Longo/fisiopatologia , Masculino , Pessoa de Meia-Idade , Moxifloxacina , Receptores de Lisoesfingolipídeo/metabolismo , Medição de Risco , Receptores de Esfingosina-1-Fosfato , Tiazóis/administração & dosagem , Tiazóis/farmacocinética , Fatores de Tempo , Adulto Jovem
13.
Ann Noninvasive Electrocardiol ; 20(4): 368-77, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25367715

RESUMO

BACKGROUND: ECG assessment with exposure response analysis applied to data from First-in-Man studies has been proposed to replace the thorough QT study for the detection of small QT effects. METHODS: Data from five thorough QT studies, three with moxifloxacin, one study with a drug with a large QTc effect (∼25 ms) and one with ketoconazole with a smaller QT effect (∼8 ms) were used. By subsampling, studies with 6-18 subjects on drug and six on placebo were simulated 1000 times per sample size to assess whether small QTc effects using ICH E14 criteria could be excluded and the impact of sample size on the estimate and variability of the slope of the concentration/QTc relation. RESULTS: With a sample size of nine or more on drug and six on placebo, the fraction of "false negative studies" was at or below 5% with data from the studies with moxifloxacin and from the drug with a large QTc effect. With the same sample size and no underlying QTc effect (placebo), the fraction of studies in which an effect above 10 ms could be excluded was above 85%. A treatment effect in the linear concentration-effect model resulted in a lower proportion of "false negatives." Sample size had little influence on the average slope estimate of the concentration/QTc relationship. CONCLUSIONS: For drugs with a QTc effect of around 12-14 ms, exposure response analysis applied to First-in-Man studies with careful ECG assessment can be used to replace the through QT study.


Assuntos
Eletrocardiografia/efeitos dos fármacos , Fluoroquinolonas/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Cetoconazol/farmacologia , Inibidores do Citocromo P-450 CYP3A/farmacologia , Relação Dose-Resposta a Droga , Humanos , Moxifloxacina , Inibidores da Topoisomerase II/farmacologia
14.
Br J Clin Pharmacol ; 79(3): 477-91, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25223836

RESUMO

AIM: Selisistat (SEN0014196), a first-in-class SirT1 inhibitor, is being developed as a disease-modifying therapy for Huntington's disease. This first-in-human study investigated the safety, pharmacokinetics and pharmacogenomics of single and multiple doses of selisistat in healthy male and female subjects. METHOD: In this double-blind, randomized, placebo-controlled study, seven cohorts of eight subjects received a single dose of selisistat at dose levels of 5, 25, 75, 150, 300 and 600 mg and four cohorts of eight subjects were administered 100, 200 and 300 mg once daily for 7 days. Blood sampling and safety assessments were conducted throughout the study. RESULTS: Selisistat was rapidly absorbed and systemic exposure increased in proportion to dose in the 5-300 mg range. Steady-state plasma concentrations were achieved within 4 days of repeated dosing. The incidence of drug related adverse events showed no correlation with dose level or number of doses received and was comparable with the placebo group. No serious adverse events were reported and no subjects were withdrawn due to adverse events. There were no trends in clinical laboratory parameters or vital signs. No trends in heart rate or ECG parameters, including the QTc interval and T-wave morphology, were observed. There were no findings in physical or neurological examinations or postural control. Transcriptional alteration was observed in peripheral blood. CONCLUSION: Selisistat was safe and well tolerated by healthy male and female subjects after single doses up to 600 mg and multiple doses up to 300 mg day(-1).


Assuntos
Carbazóis/efeitos adversos , Carbazóis/farmacocinética , Eletrocardiografia/efeitos dos fármacos , Sirtuína 1/antagonistas & inibidores , Transcriptoma/efeitos dos fármacos , Adolescente , Adulto , Área Sob a Curva , Disponibilidade Biológica , Carbazóis/administração & dosagem , Carbazóis/sangue , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Voluntários Saudáveis , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
15.
Ann Noninvasive Electrocardiol ; 19(6): 582-94, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25200912

RESUMO

BACKGROUND: Guanfacine (Intuniv) is a centrally active alpha-2A adrenergic agonist for the new indication of attention-deficit/hyperactivity disorder. QTc (QTcF and QTcNi) was prolonged at both therapeutic (4 mg) and supratherapeutic (8 mg) doses of a thorough QT study even though guanfacine has had a safe clinical history of over 3 million prescriptions for the treatment of hypertension. In an attempt to understand this disparity, retrospective evaluation of the continuous ECG data utilized dynamic beat-to-beat and ECG restitution analyses was performed. METHODS: Sixty healthy subjects using 24-hour Holters were examined in a 3-arm, placebo- and positive-controlled, double-blind crossover study for effects on beat-to-beat QT, TQ, and RR intervals. RESULTS: ECG restitution analyses indicated that, at all time points, a disproportionate effect to increase the TQ interval (rest) occurred more in relationship to each QT interval lengthening resulting in a placebo-adjusted reduced QT/TQ ratio of 21% after 4 mg and 31% after 8 mg (both antiarrhythmic responses). Additionally, the percentage of time and magnitude of stress on the heart, as measured by the upper limits of the QT/TQ ratio, were reduced with guanfacine by 22% to 24%. In contrast to guanfacine, moxifloxacin did not show a significant improvement in any restitution parameters but reflected a trend toward proarrhythmia with an increase in the QT/TQ ratio of up to 11%. CONCLUSION: These results indicate that guanfacine causes a stabilizing effect on cardiac restitution that helps reconcile the clinical evidence for a lack of arrhythmia liability despite apparent increases in typical QT/QTc prolongation measures.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/farmacologia , Arritmias Cardíacas/induzido quimicamente , Eletrocardiografia Ambulatorial/efeitos dos fármacos , Eletrocardiografia Ambulatorial/métodos , Guanfacina/farmacologia , Síndrome do QT Longo/induzido quimicamente , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Fluoroquinolonas/administração & dosagem , Humanos , Masculino , Moxifloxacina , Valores de Referência , Estudos Retrospectivos , Medição de Risco/métodos
17.
Cancer Chemother Pharmacol ; 73(6): 1109-17, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24658627

RESUMO

PURPOSE: QT assessment of oncology drugs is generally challenging because they are genotoxic and, of necessity,they require multisite evaluation in cancer patients. Lenvatinib is not genotoxic, therefore, this thorough QT (TQT)study with lenvatinib, a multityrosine kinase inhibitor, was undertaken utilizing healthy volunteers and concentration effect modeling to project the TQT effect at high plasma levels. METHODS: Fifty-two healthy subjects randomly received single doses of lenvatinib 32 mg, placebo, or moxifloxacin 400 mg in a three-way crossover study. Serial electrocardiograms were recorded, and the effect on placebo corrected change-from-baseline QTcF (ΔΔQTcF) was evaluated. The relationship between lenvatinib plasma concentrations and QTcF was analyzed with linear mixed effects modeling. RESULTS: L envatinib mildly lowered the heart rate by 5­8 bpm during the first 12 h after dosing. ΔΔQTcF was shortened with a peak effect of −5.72 ms (90 % confidence interval (90 % CI) −7.76 to −3.69 ms) at 6 h postdosing.The upper bound of mean ΔΔQTcF did not exceed 2 ms at any time point postdosing. A concentration-dependent effect of lenvatinib on ΔΔQTcF was identified with an estimated population intercept of −2.96 ms (90 % CI −4.49 to−1.43 ms; P = 0.0016) and a negative slope of −0.0045(90 % CI −4.49 to −1.43) ms per ng/mL, respectively. The safety profile after a single dose of lenvatinib was acceptable,with adverse events (AEs) of mild-to-moderate severity and no serious AEs. CONCLUSIONS: L envatinib had no clinically relevant effect on the QTc interval. Concentration-effect modeling supports the lack of QTc prolongation at high plasma concentrations.


Assuntos
Eletrocardiografia/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Compostos de Fenilureia/farmacologia , Quinolinas/farmacologia , Adulto , Estudos Cross-Over , Feminino , Fluoroquinolonas/farmacologia , Voluntários Saudáveis , Humanos , Síndrome do QT Longo/induzido quimicamente , Masculino , Moxifloxacina , Compostos de Fenilureia/efeitos adversos , Quinolinas/efeitos adversos , Adulto Jovem
18.
Diabetes Ther ; 5(1): 141-53, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24510375

RESUMO

INTRODUCTION: Albiglutide, a selective once-weekly glucagon-like peptide-1 receptor agonist, is being developed for the treatment of type 2 diabetes mellitus. Albiglutide's effect on cardiac repolarization (QTc interval) was assessed in a randomized, double-blind, placebo-controlled, parallel-group study in healthy subjects with a nested crossover comparison for moxifloxacin. METHODS: Subjects were randomized to albiglutide (n = 85) or placebo (n = 89) and received injections of 30 mg albiglutide or placebo on Days 1 and 8 and 50 mg albiglutide or placebo on Days 15, 22, 29, and 36. In the placebo group, moxifloxacin was administered on Day -1 in half the subjects and on Day 40 in the other half. Blood samples for albiglutide plasma concentration were drawn on Days 4 and 39 and serial ECGs were extracted from continuous recordings on Days -2 (baseline), -1, 4, 39, and 40. RESULTS: Demographics were generally similar between albiglutide and placebo subjects: mean age was 29 years and BMI 25 kg/m(2). Mean change-from-baseline QTcI (∆QTcI, which was corrected for individual heart rate) on Day 4 after a single dose of albiglutide 30 mg and on Day 39 after repeat dosing with albiglutide 50 mg once weekly was similar to the placebo response. The placebo-corrected ΔQTcI (ΔΔQTcI) on both albiglutide doses was small with the largest ΔΔQTcI of 1.1 ms (upper bound of 90% CI 3.8 ms) on Day 4 and -0.6 ms (upper bound of CI 1.8 ms) on Day 39. Moxifloxacin caused the largest mean effect on ΔΔQTcI of 10.9 ms and the lower bound of the CI was above 5 ms at all preselected timepoints, thereby demonstrating assay sensitivity. Albiglutide was well tolerated and there were no clinically relevant differences in safety data between albiglutide and placebo. CONCLUSION: Albiglutide at doses up to 50 mg in healthy subjects did not prolong the QTc interval.

19.
Ann Noninvasive Electrocardiol ; 19(1): 82-9, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24460808

RESUMO

BACKGROUND: Standing invoked change in QT interval has been identified as a promising autonomic maneuver for the assessment of QT/QTc prolongation in patients with underlying heart abnormalities or as a positive control in healthy volunteers for drug studies. Criticism for its more widespread use is the high variability in reported results and the need for a more standardized methodology with defined normal ranges. METHODS: Forty healthy male subjects underwent continuous ECG collection on the day before dosing in a double-blind, placebo-controlled, randomized, single ascending dose trial. A brisk supine to standing (3 minutes) response was conducted at three time points. Results were grouped by treatment cohort or assessed as a pooled group at each time point. Maximum time and median change from baseline (ΔTmax QTcF, ΔQTcF) were calculated for each individual over sequential 30-second periods staggered by 5 seconds. RESULTS: Maximum ΔQTcF at all time points and in all groups was significant (i.e., the lower bound of 90% CI was > 5 milliseconds) which is the ICH E14 regulatory requirement for a positive control. Variability of the time to maximum response was also reduced 9-fold by the third time period. CONCLUSIONS: Standing invoked ΔQTcF can be utilized to validate the sensitivity of a study for assessment of the QT interval effect of drugs in early development. The methodology may be used to further improve its diagnostic use of long QT syndromes by reducing the variability and allowing adequate definition of normal limits.


Assuntos
Antiarrítmicos/farmacologia , Eletrocardiografia Ambulatorial/efeitos dos fármacos , Eletrocardiografia Ambulatorial/métodos , Frequência Cardíaca/fisiologia , Postura , Adolescente , Adulto , Estudos de Coortes , Relação Dose-Resposta a Droga , Método Duplo-Cego , Humanos , Masculino , Pessoa de Meia-Idade , Decúbito Dorsal , Fatores de Tempo , Adulto Jovem
20.
Ann Noninvasive Electrocardiol ; 18(6): 577-89, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24118671

RESUMO

BACKGROUND: The aim of this study was to assess the effect of high plasma levels of lomitapide and its main metabolite on ECG parameters. METHODS: In this randomized five-way cross-over thorough QT study, 56 healthy subjects were enrolled. Study treatments were administered orally for 3 days in five separate periods in which subjects were dosed with (1) a single dose of 75 mg lomitapide on Day 1 followed by a single dose of 200 mg on Day 3; (2) ketoconazole 200 mg BID; (3) ketoconazole with a single dose of 75 mg lomitapide on Day 3; (4) a single dose of 400 mg moxifloxacin on Day 3 and (5) placebo. RESULTS: Single doses of 75 and 200 mg lomitapide alone or in combination with ketoconazole caused minor changes in the change-from-baseline QTcI (ΔQTcI), whereas moxifloxacin and ketoconazole caused an increase of ΔQTcI with a peak effect at 1 and 3 hours postdosing, respectively. The largest mean placebo-corrected ΔQTcI (ΔΔQTcI) for lomitapide did not exceed 3 ms (upper bound of 90% CI: 4.7 ms) at any time points postdosing. Ketoconazole caused mild QT prolongation with mean ΔΔQTcI of 5.9 and 6.5 ms at 2 and 3 hours postdosing, and exposure-response analysis demonstrated a significantly positive slope of 1.3 ms per µg/mL (90% CI: 1.0-1.7). Moxifloxacin met the criteria for assay sensitivity. CONCLUSIONS: Lomitapide does not have an effect on cardiac repolarization. The study's ability to detect small QTc changes was demonstrated with both moxifloxacin and ketoconazole.


Assuntos
Compostos Aza/farmacologia , Benzimidazóis/sangue , Benzimidazóis/farmacologia , Eletrocardiografia/efeitos dos fármacos , Cetoconazol/farmacologia , Quinolinas/farmacologia , Inibidores de 14-alfa Desmetilase/farmacologia , Adolescente , Adulto , Benzimidazóis/administração & dosagem , Estudos Cross-Over , Relação Dose-Resposta a Droga , Esquema de Medicação , Eletrocardiografia/métodos , Feminino , Fluoroquinolonas , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Pessoa de Meia-Idade , Moxifloxacina , Valores de Referência , Fatores de Tempo , Inibidores da Topoisomerase II/farmacologia , Adulto Jovem
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