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1.
Clin Transl Sci ; 13(1): 57-66, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31343094

RESUMO

In the last decade, drug development has tackled substantial challenges to improve efficiency and facilitate access to innovative medicines. Integrated clinical protocols and the investigation of targeted oncology drugs in healthy volunteers (HVs) have emerged as modalities with an increase in scope and complexity of early clinical studies and first-in-human (FIH) studies in particular. However, limited work has been done to explore the impact of these two modalities, alone or in combination, on the scientific value and on the implementation of such articulated studies. We conducted an FIH study in HVs with an oncology targeted drug, an Mnk 1/2 small molecule inhibitor. In this article, we describe results, advantages, and limitations of an integrated clinical protocol with an oncology drug. We further discuss and indicate points to consider when designing and conducting similar scientifically and operationally demanding FIH studies.


Assuntos
Antineoplásicos/efeitos adversos , Doenças Cardiovasculares/diagnóstico , Protocolos Clínicos , Inibidores de Proteínas Quinases/efeitos adversos , Projetos de Pesquisa , Administração Oral , Adulto , Antineoplásicos/administração & dosagem , Doenças Cardiovasculares/induzido quimicamente , Eletrocardiografia , Voluntários Saudáveis , Neoplasias Hematológicas/tratamento farmacológico , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Masculino , Oncologia/métodos , Pessoa de Meia-Idade , Monitorização Ambulatorial/métodos , Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Adulto Jovem
2.
Heart Fail Rev ; 23(5): 667-691, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29736812

RESUMO

Acute heart failure (AHF) is a major burden disease, with a complex physiopathology, unsatisfactory diagnosis, treatment and a very poor prognosis. In the last two decades, a number of drugs have progressed from preclinical to early and late clinical development, but only a few of them have been approved and added to a stagnant pharmacological armamentarium. We have reviewed the data published on drugs developed for AHF since early 2000s, trying to recognise factors that have worked for a successful approval or for the stoppage of the program, in an attempt to delineate future trajectories for AHF drug development. Our review has identified limitations at both preclinical and clinical levels. At the preclinical level, the major shortcoming is represented by animal models looking at short-term endpoints which do not recapitulate the complexity of the human disease. At the clinical level, the main weakness is given by the disconnect between short-term endpoints assessed in the early stage of drug development, and medium-long-term endpoints requested in Phase 3 for regulatory approval. This is further amplified by the lack of validation and standardisation of short- and long-term endpoints; absence of predictive biomarkers; conduct of studies on heterogeneous populations; and use of different eligibility criteria, time of assessments, drug schedules and background therapies. Key goals remain a better understanding of AHF and the construction of a successful drug development program. A reasonable way to move forward resides in a strong collaboration between main stakeholders of therapeutic innovation: scientific community, industry and regulatory agencies.


Assuntos
Cardiotônicos/uso terapêutico , Desenvolvimento de Medicamentos/métodos , Insuficiência Cardíaca/tratamento farmacológico , Doença Aguda , Aprovação de Drogas , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Humanos , Peptídeo Natriurético Encefálico/uso terapêutico , Simendana/uso terapêutico
3.
Psychopharmacology (Berl) ; 197(3): 401-8, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18176855

RESUMO

RATIONALE: Ketamine induces effects resembling both positive and negative psychotic symptoms of schizophrenia. These are thought to arise through its action as an uncompetitive antagonist of the N-methyl-D-aspartate (NMDA) receptor. OBJECTIVES: We used [(123)I]CNS-1261 to study ketamine binding to NMDA receptors in healthy human controls in vivo and its relationship to positive and negative psychotic symptom induction. MATERIALS AND METHODS: Ten healthy controls underwent two single-photon emission tomography scans with [(123)I]CNS-1261. On each occasion, they received a bolus infusion of either ketamine or saline. The Brief Psychiatric Rating Scale (BPRS) was administered at the end of each scan. Predefined regions of interest were used to estimate change in volume of distribution of [(123)I]CNS-1261 following ketamine administration. Two normalised-to-cortex binding indices were also used in order to study effects of ketamine on NMDA receptor availability by region, after correction for global and nonspecific effects. RESULTS: Ketamine-induced reduction in [(123)I]CNS-1261 volume of distribution in all regions showed the strongest correlation with BPRS negative subscale (p < 0.01). With the normalised-to-cortex measures, NMDA receptor binding in middle inferior frontal cortex showed a significant correlation with BPRS negative subscale (BI1 r = 0.88, BI2 r = 95.9, p < 0.001). CONCLUSIONS: [(123)I]CNS-1261 binding was modulated by ketamine, a drug known to compete for the same site on the NMDA receptor in vitro. Ketamine may induce negative symptoms through direct inhibition of the NMDA receptor, and positive symptoms may arise through a different neurochemical pathway.


Assuntos
Guanidinas , Radioisótopos do Iodo , Ketamina/toxicidade , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/diagnóstico por imagem , Psicoses Induzidas por Substâncias/diagnóstico por imagem , Psicoses Induzidas por Substâncias/fisiopatologia , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Esquizofrenia/induzido quimicamente , Esquizofrenia/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Escalas de Graduação Psiquiátrica Breve , Relação Dose-Resposta a Droga , Guanidinas/farmacocinética , Humanos , Infusões Intravenosas , Radioisótopos do Iodo/farmacocinética , Ketamina/administração & dosagem , Ketamina/farmacocinética , Masculino , Receptores de N-Metil-D-Aspartato/metabolismo , Método Simples-Cego
4.
Psychopharmacology (Berl) ; 183(1): 1-12, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16160876

RESUMO

RATIONALE: Sustained-release (SR) bupropion enhances quit rates of smokers, generally decreases tobacco withdrawal, and in some studies, reduces craving. OBJECTIVE: Investigate the effects of SR bupropion on craving and withdrawal during cigarette abstinence. METHODS: Twenty three smokers participated in three 17-day periods composed of 14 out-patient days followed by 3 (72 h) in-patient days. During the out-patient days, subjects received SR bupropion, placebo, or no drug. During the in-patient days, subjects were abstinent from cigarettes on two occasions while receiving either SR bupropion or placebo and smoked freely during the other occasion. SR bupropion was titrated over the first three out-patient days followed by a fixed dose (300 mg/day) for 14 days (including the three in-patient abstinence days). Cigarette craving, withdrawal, and selected physiological measures were assessed repeatedly over the 72-h periods. RESULTS: During the 72-h periods, craving intensity was significantly lower with free smoke and SR bupropion than with placebo, and significantly lower during free smoke than during SR bupropion. Overall withdrawal symptoms were significantly lower with free smoke than with either placebo or SR bupropion. Among individual withdrawal symptoms (excluding craving), appetite increase was significantly reduced during SR bupropion compared to placebo. During placebo and SR bupropion, craving intensity displayed a circadian pattern that was different from that observed during free smoke. CONCLUSIONS: SR bupropion reduced craving and appetite increase during smoking abstinence. These findings support the hypothesis that craving and withdrawal symptoms may be controlled by distinct central nervous system pathways.


Assuntos
Antidepressivos de Segunda Geração/uso terapêutico , Bupropiona/uso terapêutico , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Adulto , Antidepressivos de Segunda Geração/administração & dosagem , Apetite/efeitos dos fármacos , Bupropiona/administração & dosagem , Ritmo Circadiano , Estudos Cross-Over , Preparações de Ação Retardada , Método Duplo-Cego , Feminino , Humanos , Masculino , Nicotina/metabolismo , Troca Gasosa Pulmonar/efeitos dos fármacos , Saliva/efeitos dos fármacos , Saliva/metabolismo , Abandono do Hábito de Fumar/métodos , Síndrome de Abstinência a Substâncias/metabolismo , Inquéritos e Questionários , Fatores de Tempo
5.
Pharmacol Biochem Behav ; 77(1): 103-9, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14724047

RESUMO

We investigated resting EEG and auditory P300 during free smoking and 36 h of enforced smoking abstinence in 12 healthy volunteers. Resting EEG was recorded on 19 scalp leads and auditory P300 was obtained by an oddball paradigm task. Spectral analysis of EEG (absolute and relative power, mean frequency), latency and amplitude of auditory P300 were considered for statistical analysis. EEG changes were not significant during free smoking but were significant during smoking abstinence. Theta absolute power increased by +57% (P<.001), whereas alpha and delta absolute power increased by +26% (P<.01) and +19% (P<.01), respectively; theta absolute power change was delayed and prolonged. Alpha mean frequency reduced by -0.31 Hz (P<.001), whereas delta, theta and beta1 mean frequency increased by +0.13 Hz (P<.05), +0.09 Hz (P<.05) and +0.23 Hz (P<.01), respectively. Auditory P300 amplitude and latency were unaffected by smoking abstinence. Resting EEG, but not auditory P300, was sufficiently sensitive to detect changes during enforced smoking abstinence, and EEG bands had different temporal changes.


Assuntos
Eletroencefalografia , Potenciais Evocados P300/fisiologia , Potenciais Evocados Auditivos/fisiologia , Abandono do Hábito de Fumar , Fumar/fisiopatologia , Adulto , Análise de Variância , Estudos Cross-Over , Método Duplo-Cego , Eletroencefalografia/estatística & dados numéricos , Humanos , Masculino , Sensibilidade e Especificidade , Abandono do Hábito de Fumar/estatística & dados numéricos
6.
Eur J Nucl Med Mol Imaging ; 30(4): 572-80, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12552334

RESUMO

The quantitative determination of regional cerebral blood flow (rCBF) is important in certain clinical and research applications. The disadvantage of most quantitative methods using H(2)(15)O positron emission tomography (PET) is the need for arterial blood sampling. In this study a new non-invasive method for rCBF quantification was evaluated. The method is based on the washout rate of H(2)(15)O following intravenous injection. All results were obtained with Alpert's method, which yields maps of the washin parameter K(1) (rCBF(K1)) and the washout parameter k(2) (rCBF(k2)). Maps of rCBF(K1) were computed with measured arterial input curves. Maps of rCBF(k2*) were calculated with a standard input curve which was the mean of eight individual input curves. The mean of grey matter rCBF(k2*) (CBF(k2*)) was then compared with the mean of rCBF(K1) (CBF(K1)) in ten healthy volunteer smokers who underwent two PET sessions on day 1 and day 3. Each session consisted of three serial H(2)(15)O scans. Reproducibility was analysed using the rCBF difference scan 3-scan 2 in each session. The perfusion reserve (PR = rCBF(acetazolamide)-rCBF(baseline)) following acetazolamide challenge was calculated with rCBF(k2*) (PR(k2*)) and rCBF(K1) (PR(K1)) in ten patients with cerebrovascular disease. The difference CBF(k2*)-CBF(K1) was 5.90+/-8.12 ml/min/100 ml (mean+/-SD, n=55). The SD of the scan 3-scan 1 difference was 6.1% for rCBF(k2*) and rCBF(K1), demonstrating a high reproducibility. Perfusion reserve values determined with rCBF(K1) and rCBF(k2*) were in high agreement (difference PR(k2*)-PR(K1)=-6.5+/-10.4%, PR expressed in percentage increase from baseline). In conclusion, a new non-invasive method for the quantitative determination of rCBF is presented. The method is in good agreement with Alpert's original method and the reproducibility is high. It does not require arterial blood sampling, yields quantitative voxel-by-voxel maps of rCBF, and is computationally efficient and easy to implement.


Assuntos
Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular , Transtornos Cerebrovasculares/diagnóstico , Radioisótopos de Oxigênio , Técnica de Diluição de Radioisótopos , Adulto , Coleta de Amostras Sanguíneas , Encéfalo/fisiopatologia , Transtornos Cerebrovasculares/sangue , Transtornos Cerebrovasculares/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Tomografia Computadorizada de Emissão/métodos , Água
7.
Psychopharmacology (Berl) ; 164(2): 177-87, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12404080

RESUMO

RATIONALE: Research on the effects of nicotine abstinence and nicotine replacement has not provided consistent information about the impact of replacement therapies on tobacco withdrawal and craving. OBJECTIVE: . This study investigated craving and withdrawal symptoms over a 72-h period of abstinence from cigarettes. METHODS: . Twenty-four healthy volunteers, not intending to quit smoking, were housed in an experimental unit during three 72-h conditions, consisting of either free smoking, enforced smoking cessation with nicotine replacement therapy (NRT) patches, or enforced smoking cessation with placebo patches. The conditions were adhered to using a randomized crossover design, each separated by at least 10 days of washout. Patches, administered in a double-blind fashion, were given as nicotine (21 mg/24 h) and placebo every 24 h. Self-reported cigarette craving and withdrawal were assessed using multi-item scales at fixed intervals over each condition period. Urinary and plasma cortisol levels were also assayed at fixed intervals over each period. RESULTS: Craving intensity was significantly lower with free smoke than with placebo and with NRT patches than with placebo. No difference in craving levels was found between those who smoked or those who had NRT patches. Withdrawal symptoms were significantly lower with free smoke than with either placebo or NRT patches, but there was no difference in levels of withdrawal between those on NRT patches and those on placebo. During the placebo and NRT patch periods, craving intensity displayed a circadian rhythm, with craving levels lowest in the morning and peaking in the evening. Nicotine delivered via the patch had no impact on these circadian variations in craving. There was no evidence of systematic temporal variations in craving levels during the free smoking period. CONCLUSIONS: The data suggested that craving and withdrawal symptoms may be sustained by different physiological pathways, and that only selected components of cigarette craving are influenced by NRT.


Assuntos
Nicotina/uso terapêutico , Abandono do Hábito de Fumar , Fumar/tratamento farmacológico , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Administração Cutânea , Adulto , Pressão Sanguínea/efeitos dos fármacos , Monóxido de Carbono/metabolismo , Cotinina/química , Estudos Cross-Over , Método Duplo-Cego , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Hidrocortisona/sangue , Hidrocortisona/metabolismo , Hidrocortisona/urina , Masculino , Nicotina/administração & dosagem , Distribuição Aleatória , Saliva/efeitos dos fármacos , Saliva/metabolismo , Fumar/fisiopatologia , Fumar/psicologia , Síndrome de Abstinência a Substâncias/fisiopatologia , Síndrome de Abstinência a Substâncias/psicologia , Inquéritos e Questionários
8.
Br J Clin Pharmacol ; 54(4): 407-14, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12392589

RESUMO

AIMS: To investigate whether saliva is a useful alternative to plasma for routine monitoring of nicotine and evaluate the predictive performances of saliva and plasma concentration on craving estimated by a Tiffany Questionnaire on Smoking Urge-Brief Form. METHODS: Thirteen healthy smokers were enrolled in a randomized, two period, crossover trial. Linear and power models were evaluated to predict the plasma nicotine concentrations from the saliva measurements, whereas a population PK/PD indirect response model was used to predict craving using either saliva or plasma nicotine concentration as the independent variable. RESULTS: The results of the analysis revealed that the power model was preferred over the linear one. The bias on the predicted plasma concentrations was of 0.47 ng ml-1 with a 95% confidence interval of [-0.57, 1.52] and a precision of 5.68 ng ml-1. The placebo effect model was initially fitted to data, then the indirect response approach (with inhibition in k(in)) was used to model the craving scores using plasma and saliva nicotine concentrations as independent variables. The two indirect response PK/PD models based on saliva and plasma nicotine concentrations, adequately described the onset, extent, and duration of craving. The maximal inhibition I(max) was 0.722 and 1 for saliva and plasma concentrations while the estimated nicotine concentrations giving 50% of the maximal inhibition were 269 ng ml-1 and 24.3 ng ml-1 for saliva and plasma, respectively. CONCLUSIONS: A good correlation between plasma and saliva nicotine concentrations has been found using a power model. Comparable values of bias and precision on the model-predicted craving indicate that plasma and saliva concentration can equally well be used to predict the onset of tobacco withdrawal induced craving. Analysis of saliva definitely offers a potentially more attractive way to assess nicotine concentration values, as samples can be collected easily and noninvasively. In addition, saliva sampling avoids the pain and discomfort involved in venepuncture. In studies that assess psychological measures, such as subjective mood, blood collection could present a possible confounding factor because of the anxiety and pain that accompanies it. For these reasons saliva can reasonably be considered as the ideal sampling site for all clinical studies conducted for the evaluation of the potential activity of drugs on nicotine deprivation symptoms.


Assuntos
Nicotina/análise , Agonistas Nicotínicos/análise , Saliva/química , Fumar/metabolismo , Síndrome de Abstinência a Substâncias/metabolismo , Adulto , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nicotina/sangue , Nicotina/farmacocinética , Agonistas Nicotínicos/sangue , Agonistas Nicotínicos/farmacocinética , Valor Preditivo dos Testes , Sensibilidade e Especificidade
9.
J Cereb Blood Flow Metab ; 22(9): 1149-56, 2002 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12218421

RESUMO

While H2(15)O positron emission tomography (PET) is still the gold standard in the quantitative assessment of cerebral perfusion (rCBF), its technical challenge, limited availability, and radiation exposure are disadvantages of the method. Recent work demonstrated the feasibility of magnetic resonance (MR) for quantitative cerebral perfusion imaging. There remain open questions, however, especially regarding reproducibility. The main purpose of this study was to assess the accuracy and reproducibility of MR-derived flow values to those derived from H2(15)O PET. Positron emission tomography and MR perfusion imaging was performed in 20 healthy male volunteers, who were chronic smokers, on day 1 and day 3 of a 4-day hospitalization. Subjects were randomly assigned to one of two groups, each with 10 subjects. One group was allowed to smoke as usual during the hospitalization, while the other group stopped smoking from day 2. Positron emission tomography and MR images were coregistered and rCBF was determined in two regions of interest, defined over gray matter (gm) and white matter (wm), yielding rCBF(PET)gm, rCBF(MR)gm, rCBF(PET)wm, and rCBF(MR)wm. Bland-Altman analysis was used to investigate reproducibility by assessing the difference rCBFday3 - rCBFday1 in eight continual-smoker volunteers. The analysis showed a good reproducibility for PET, but not for MR. Mean +/- SD of the difference rCBFday3 - rCBFday1 in gray matter was 6.35 +/- 21.06 and 0.49 +/- 5.27 mL x min(-1) x 100 g(-1) for MR and PET, respectively; the corresponding values in white matter were 2.60 +/- 15.64 and -1.14 +/- 4.16 mL x min(-1) x 100 g(-1). The Bland-Altman analysis was also used to assess MRI and PET agreement comparing rCBF measured on day 1. The analysis demonstrated a reasonably good agreement of MR and PET in white matter (rCBF(PET)wm - rCBF(MR)wm; -0.09 +/- 7.23 mL x min(-1) x 100 g(-1)), while in gray matter a reasonable agreement was only achieved after removing vascular artifacts in the MR perfusion maps (rCBF(PET)gm - rCBF(MR)gm; -11.73 +/- 14.52 mL x min(-1) x 100 g(-1)). In line with prior work, these results demonstrate that reproducibility was overall considerably better for PET than for MR. Until reproducibility is improved and vascular artifacts are efficiently removed, MR is not suitable for reliable quantitative perfusion measurements.


Assuntos
Circulação Cerebrovascular/fisiologia , Imageamento por Ressonância Magnética , Radioisótopos de Oxigênio , Tomografia Computadorizada de Emissão , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Reprodutibilidade dos Testes , Fumar , Fatores de Tempo
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