RESUMO
PURPOSE: Cardiac dysfunction risk associated with intravenous trastuzumab (H IV) treatment may differ in real-world practice versus randomized trials. We investigated cardiac events in patients with HER2-positive early breast cancer (EBC) treated with H IV as adjuvant therapy in routine practice. METHODS: The observational study of cardiac events in patients with HER2-positive EBC treated with Herceptin (OHERA; NCT01152606) enrolled patients with stage I-IIIb disease eligible for H IV in the adjuvant setting per the European Summary of Product Characteristics (SmPC). Primary outcomes were symptomatic congestive heart failure incidence (CHF; New York Heart Association class II-IV) and cardiac death. Patient visits/assessments were per local practice. RESULTS: 3733 Patients received ≥ 1 H IV dose per local practice; 88.9% received H IV for > 300 days (median follow-up: ~ 5 years). Prior to disease recurrence (if any), symptomatic CHF occurred in 106 patients (2.8%); 6 (0.2%) cardiac deaths occurred (5 in patients with cardiac disease history). Median time to symptomatic CHF onset was 5.7 months (95% CI 5.3-6.5); 77/106 (72.6%) patients with symptomatic CHF achieved resolution. CHF incidence was higher in patients ≥ 65 years, and those with pre-existing cardiac conditions, hypertension, or left ventricular ejection fraction ≤ 55% at baseline. CONCLUSIONS: OHERA is the largest prospective observational study to investigate the cardiac safety of H IV as adjuvant EBC therapy in a real-world setting. Symptomatic CHF and cardiac event incidences were consistent with randomized trials in this setting and baseline risk factors identified in the H IV European SmPC.
Assuntos
Antineoplásicos Imunológicos/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Cardiotoxicidade/epidemiologia , Trastuzumab/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Cardiotoxicidade/etiologia , Feminino , Coração/efeitos dos fármacos , Humanos , Incidência , Pessoa de Meia-Idade , Estudos Prospectivos , Receptor ErbB-2 , Adulto JovemRESUMO
Background: The phase III ALEX study in patients with treatment-naive advanced anaplastic lymphoma kinase mutation-positive (ALK+) non-small-cell lung cancer (NSCLC) met its primary end point of improved progression-free survival (PFS) with alectinib versus crizotinib. Here, we present detailed central nervous system (CNS) efficacy data from ALEX. Patients and methods: Overall, 303 patients aged ≥18 years underwent 1:1 randomization to receive twice-daily doses of alectinib 600 mg or crizotinib 250 mg. Brain imaging was conducted in all patients at baseline and every subsequent 8 weeks. End points (analyzed by subgroup: patients with/without baseline CNS metastases; patients with/without prior radiotherapy) included PFS, CNS objective response rate (ORR), and time to CNS progression. Results: In total, 122 patients had Independent Review Committee-assessed baseline CNS metastases (alectinib, n = 64; crizotinib, n = 58), 43 had measurable lesions (alectinib, n = 21; crizotinib, n = 22), and 46 had received prior radiotherapy (alectinib, n = 25; crizotinib, n = 21). Investigator-assessed PFS with alectinib was consistent between patients with baseline CNS metastases [hazard ratio (HR) 0.40, 95% confidence interval (CI): 0.25-0.64] and those without (HR 0.51, 95% CI: 0.33-0.80, P interaction = 0.36). Similar results were seen in patients regardless of prior radiotherapy. Time to CNS progression was significantly longer with alectinib versus crizotinib and comparable between patients with and without baseline CNS metastases (P < 0.0001). CNS ORR was 85.7% with alectinib versus 71.4% with crizotinib in patients who received prior radiotherapy and 78.6% versus 40.0%, respectively, in those who had not. Conclusion: Alectinib demonstrated superior CNS activity and significantly delayed CNS progression versus crizotinib in patients with previously untreated, advanced ALK+ NSCLC, irrespective of prior CNS disease or radiotherapy. Clinical trial registration: ClinicalTrials.gov NCT02075840.
Assuntos
Quinase do Linfoma Anaplásico/genética , Neoplasias Encefálicas/terapia , Carbazóis/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/terapia , Crizotinibe/uso terapêutico , Neoplasias Pulmonares/terapia , Piperidinas/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Quinase do Linfoma Anaplásico/antagonistas & inibidores , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Encéfalo/efeitos da radiação , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/secundário , Carbazóis/farmacologia , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/secundário , Quimiorradioterapia/métodos , Crizotinibe/farmacologia , Progressão da Doença , Feminino , Humanos , Pulmão/diagnóstico por imagem , Pulmão/efeitos dos fármacos , Pulmão/efeitos da radiação , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Piperidinas/farmacologia , Resultado do Tratamento , Carga Tumoral/efeitos dos fármacos , Carga Tumoral/efeitos da radiação , Adulto JovemRESUMO
BACKGROUND: To summarize the available evidence on the effectiveness of psychological interventions for patients with post-traumatic stress disorder (PTSD). METHOD: We searched bibliographic databases and reference lists of relevant systematic reviews and meta-analyses for randomized controlled trials that compared specific psychological interventions for adults with PTSD symptoms either head-to-head or against control interventions using non-specific intervention components, or against wait-list control. Two investigators independently extracted the data and assessed trial characteristics. RESULTS: The analyses included 4190 patients in 66 trials. An initial network meta-analysis showed large effect sizes (ESs) for all specific psychological interventions (ESs between -1.10 and -1.37) and moderate effects of psychological interventions that were used to control for non-specific intervention effects (ESs -0.58 and -0.62). ES differences between various types of specific psychological interventions were absent to small (ES differences between 0.00 and 0.27). Considerable between-trial heterogeneity occurred (τ²= 0.30). Stratified analyses revealed that trials that adhered to DSM-III/IV criteria for PTSD were associated with larger ESs. However, considerable heterogeneity remained. Heterogeneity was reduced in trials with adequate concealment of allocation and in large-sized trials. We found evidence for small-study bias. CONCLUSIONS: Our findings show that patients with a formal diagnosis of PTSD and those with subclinical PTSD symptoms benefit from different psychological interventions. We did not identify any intervention that was consistently superior to other specific psychological interventions. However, the robustness of evidence varies considerably between different psychological interventions for PTSD, with most robust evidence for cognitive behavioral and exposure therapies.
Assuntos
Psicoterapia/normas , Transtornos de Estresse Pós-Traumáticos/terapia , Resultado do Tratamento , HumanosRESUMO
BACKGROUND: Erythropoiesis-stimulating agents (ESAs) reduce the need for red blood cell transfusions; however, they increase the risk of thromboembolic events and mortality. The impact of ESAs on quality of life (QoL) is controversial and led to different recommendations of medical societies and authorities in the USA and Europe. We aimed to critically evaluate and quantify the effects of ESAs on QoL in cancer patients. METHODS: We included data from randomised controlled trials (RCTs) on the effects of ESAs on QoL in cancer patients. Randomised controlled trials were identified by searching electronic data bases and other sources up to January 2011. To reduce publication and outcome reporting biases, we included unreported results from clinical study reports. We conducted meta-analyses on fatigue- and anaemia-related symptoms measured with the Functional Assessment of Cancer Therapy-Fatigue (FACT-F) and FACT-Anaemia (FACT-An) subscales (primary outcomes) or other validated instruments. RESULTS: We identified 58 eligible RCTs. Clinical study reports were available for 27% (4 out of 15) of the investigator-initiated trials and 95% (41 out of 43) of the industry-initiated trials. We excluded 21 RTCs as we could not use their QoL data for meta-analyses, either because of incomplete reporting (17 RCTs) or because of premature closure of the trial (4 RCTs). We included 37 RCTs with 10581 patients; 21 RCTs were placebo controlled. Chemotherapy was given in 27 of the 37 RCTs. The median baseline haemoglobin (Hb) level was 10.1 g dl(-1); in 8 studies ESAs were stopped at Hb levels below 13 g dl(-1) and in 27 above 13 g dl(-1). For FACT-F, the mean difference (MD) was 2.41 (95% confidence interval (95% CI) 1.39-3.43; P<0.0001; 23 studies, n=6108) in all cancer patients and 2.81 (95% CI 1.73-3.90; P<0.0001; 19 RCTs, n=4697) in patients receiving chemotherapy, which was below the threshold (≥ 3) for a clinically important difference (CID). Erythropoiesis-stimulating agents had a positive effect on anaemia-related symptoms (MD 4.09; 95% CI 2.37-5.80; P=0.001; 14 studies, n=2765) in all cancer patients and 4.50 (95% CI 2.55-6.45; P<0.0001; 11 RCTs, n=2436) in patients receiving chemotherapy, which was above the threshold (≥ 4) for a CID. Of note, this effect persisted when we restricted the analysis to placebo-controlled RCTs in patients receiving chemotherapy. There was some evidence that the MDs for FACT-F were above the threshold for a CID in RCTs including cancer patients receiving chemotherapy with Hb levels below 12 g dl(-1) at baseline and in RCTs stopping ESAs at Hb levels above 13 g dl(-1). However, these findings for FACT-F were not confirmed when we restricted the analysis to placebo-controlled RCTs in patients receiving chemotherapy. CONCLUSIONS: In cancer patients, particularly those receiving chemotherapy, we found that ESAs provide a small but clinically important improvement in anaemia-related symptoms (FACT-An). For fatigue-related symptoms (FACT-F), the overall effect did not reach the threshold for a CID.
Assuntos
Anemia/tratamento farmacológico , Fadiga/sangue , Hematínicos/uso terapêutico , Neoplasias/sangue , Anemia/sangue , Eritropoese/efeitos dos fármacos , Humanos , Neoplasias/tratamento farmacológico , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do TratamentoRESUMO
BACKGROUND: Chronic pain is associated with generalized hypersensitivity and impaired endogenous pain modulation (conditioned pain modulation; CPM). Despite extensive research, their prevalence in chronic pain patients is unknown. This study investigated the prevalence and potential determinants of widespread central hypersensitivity and described the distribution of CPM in chronic pain patients. METHODS: We examined 464 consecutive chronic pain patients for generalized hypersensitivity and CPM using pressure algometry at the second toe and cold pressor test. Potential determinants of generalized central hypersensitivity were studied using uni- and multivariate regression analyses. Prevalence of generalized central hypersensitivity was calculated for the 5th, 10th and 25th percentile of normative values for pressure algometry obtained by a previous large study on healthy volunteers. CPM was addressed on a descriptive basis, since normative values are not available. RESULTS: Depending on the percentile of normative values considered, generalized central hypersensitivity affected 17.5-35.3% of patients. 23.7% of patients showed no increase in pressure pain threshold after cold pressor test. Generalized central hypersensitivity was more frequent and CPM less effective in women than in men. Unclearly classifiable pain syndromes showed higher frequencies of generalized central hypersensitivity than other pain syndromes. CONCLUSIONS: Although prevalent in chronic pain, generalized central hypersensitivity is not present in every patient. An individual assessment is therefore required in order to detect altered pain processing. The broad basic knowledge about central hypersensitivity now needs to be translated into concrete clinical consequences, so that patients can be offered an individually tailored mechanism-based treatment.
Assuntos
Dor Crônica/fisiopatologia , Hiperalgesia/epidemiologia , Adulto , Idoso , Dor Crônica/complicações , Feminino , Humanos , Hiperalgesia/complicações , Masculino , Pessoa de Meia-Idade , Medição da Dor/métodos , Limiar da Dor/fisiologia , Pressão , PrevalênciaRESUMO
OBJECTIVES: Femoroacetabular impingement is proposed to cause early osteoarthritis (OA) in the non-dysplastic hip. We previously reported on the prevalence of femoral deformities in a young asymptomatic male population. The aim of this study was to determine the prevalence of both femoral and acetabular types of impingement in young females. METHODS: We conducted a population-based cross-sectional study of asymptomatic young females. All participants completed a set of questionnaires and underwent clinical examination of the hip. A random sample was subsequently invited to obtain magnetic resonance images (MRI) of the hip. All MRIs were read for cam-type deformities, increased acetabular depths, labral lesions, and impingement pits. Prevalence estimates of cam-type deformities and increased acetabular depths were estimated, and relationships between deformities and signs of joint damage were examined using logistic regression models. RESULTS: The study included 283 subjects, and 80 asymptomatic females with a mean age of 19.3 years attended MRI. Fifteen showed some evidence of cam-type deformities, but none were scored to be definite. The overall prevalence was therefore 0% [95% confidence interval (95% CI) 0-5%]. The prevalence of increased acetabular depth was 10% (95% CI 5-19). No association was found between increased acetabular depth and decreased internal rotation of the hip. Increased acetabular depth was not associated with signs of labral damage. CONCLUSIONS: Definite cam-type deformities in women are rare compared to men, whereas the prevalence of increased acetabular depth is higher, suggesting that femoroacetabular impingement has different gender-related biomechanical mechanisms.
Assuntos
Impacto Femoroacetabular/epidemiologia , Acetábulo/patologia , Adolescente , Estudos Transversais , Feminino , Impacto Femoroacetabular/diagnóstico , Impacto Femoroacetabular/patologia , Impacto Femoroacetabular/fisiopatologia , Articulação do Quadril/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Prevalência , Amplitude de Movimento Articular , Fatores Sexuais , Suíça/epidemiologia , Adulto JovemRESUMO
The aim of this study was to investigate treatment failure (TF) in hospitalised community-acquired pneumonia (CAP) patients with regard to initial antibiotic treatment and economic impact. CAP patients were included in two open, prospective multicentre studies assessing the direct costs for in-patient treatment. Patients received treatment either with moxifloxacin (MFX) or a nonstandardised antibiotic therapy. Any change in antibiotic therapy after >72 h of treatment to a broadened antibiotic spectrum was considered as TF. Overall, 1,236 patients (mean ± SD age 69.6 ± 16.8 yrs, 691 (55.9%) male) were included. TF occurred in 197 (15.9%) subjects and led to longer hospital stay (15.4 ± 7.3 days versus 9.8 ± 4.2 days; p < 0.001) and increased median treatment costs (2,206 versus 1,284; p<0.001). 596 (48.2%) patients received MFX and witnessed less TF (10.9% versus 20.6%; p < 0.001). After controlling for confounders in multivariate analysis, adjusted risk of TF was clearly reduced in MFX as compared with ß-lactam monotherapy (adjusted OR for MFX 0.43, 95% CI 0.27-0.68) and was more comparable with a ß-lactam plus macrolide combination (BLM) (OR 0.68, 95% CI 0.38-1.21). In hospitalised CAP, TF is frequent and leads to prolonged hospital stay and increased treatment costs. Initial treatment with MFX or BLM is a possible strategy to prevent TF, and may thus reduce treatment costs.
Assuntos
Antibacterianos/uso terapêutico , Compostos Aza/uso terapêutico , Macrolídeos/uso terapêutico , Pneumonia/tratamento farmacológico , Quinolinas/uso terapêutico , beta-Lactamas/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/economia , Quimioterapia Combinada/economia , Feminino , Fluoroquinolonas , Custos de Cuidados de Saúde , Humanos , Tempo de Internação/economia , Masculino , Pessoa de Meia-Idade , Moxifloxacina , Pneumonia/economia , Falha de TratamentoRESUMO
OBJECTIVE: To determine the performance of a newly developed examination chair as compared with the clinical standard of assessing internal rotation (IR) of the flexed hip with a goniometer. METHODS: The examination chair allowed measurement of IR in a sitting position simultaneously in both hips, with hips and knees flexed 90 degrees, lower legs hanging unsupported and a standardized load of 5 kg applied to both ankles using a bilateral pulley system. Clinical assessment of IR was performed in supine position with hips and knees flexed 90 degrees using a goniometer. Within the framework of a population-based inception cohort study, we calculated inter-observer agreement in two samples of 84 and 64 consecutive, unselected young asymptomatic males using intra-class correlation coefficients (ICC) and determined the correlation between IR assessed with examination chair and clinical assessment. RESULTS: Inter-observer agreement was excellent for the examination chair (ICC right hip, 0.92, 95% confidence interval [CI] 0.89-0.95; ICC left hip, 0.90, 95% CI 0.86-0.94), and considerably higher than that seen with clinical assessment (ICC right hip, 0.65, 95% CI 0.49-0.77; ICC left hip, 0.69, 95% CI 0.54-0.80, P for difference in ICC between examination chair and clinical assessment Assuntos
Articulação do Quadril/fisiologia
, Quadril/anatomia & histologia
, Osteoartrite do Quadril/fisiopatologia
, Amplitude de Movimento Articular
, Fenômenos Biomecânicos
, Desenho de Equipamento
, Equipamentos e Provisões
, Humanos
, Masculino
, Valores de Referência
, Rotação
, Suíça
, Adulto Jovem
RESUMO
OBJECTIVE: To determine whether treatment with spinal manipulative therapy (SMT) administered in addition to standard care is associated with clinically relevant early reductions in pain and analgesic consumption. METHODS: 104 patients with acute low back pain were randomly assigned to SMT in addition to standard care (n = 52) or standard care alone (n = 52). Standard care consisted of general advice and paracetamol, diclofenac or dihydrocodeine as required. Other analgesic drugs or non-pharmacological treatments were not allowed. Primary outcomes were pain intensity assessed on the 11-point box scale (BS-11) and analgesic use based on diclofenac equivalence doses during days 1-14. An extended follow-up was performed at 6 months. RESULTS: Pain reductions were similar in experimental and control groups, with the lower limit of the 95% CI excluding a relevant benefit of SMT (difference 0.5 on the BS-11, 95% CI -0.2 to 1.2, p = 0.13). Analgesic consumptions were also similar (difference -18 mg diclofenac equivalents, 95% CI -43 mg to 7 mg, p = 0.17), with small initial differences diminishing over time. There were no differences between groups in any of the secondary outcomes and stratified analyses provided no evidence for potential benefits of SMT in specific patient groups. The extended follow-up showed similar patterns. CONCLUSIONS: SMT is unlikely to result in relevant early pain reduction in patients with acute low back pain.
Assuntos
Dor Lombar/reabilitação , Manipulação da Coluna , Doença Aguda , Adulto , Analgésicos não Narcóticos/administração & dosagem , Analgésicos não Narcóticos/uso terapêutico , Analgésicos Opioides/uso terapêutico , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/uso terapêutico , Terapia Combinada , Esquema de Medicação , Feminino , Humanos , Dor Lombar/tratamento farmacológico , Masculino , Manipulação da Coluna/efeitos adversos , Pessoa de Meia-Idade , Medição da Dor/métodos , Resultado do Tratamento , Adulto JovemRESUMO
The diffusion of drug substance in a closed three-compartment model through a mucus layer to equilibrium is simulated by available pharmacokinetic programs. The obtained curves conform very well to the values experimentally found. If mucus is replaced by buffer solution an explicit equation from the literature, the method used and the experimental findings give the same results. Examination of the rate constants k1 for the diffusion in, kD through and k2 from the mucus shows the significance of the relation k1/k2 > 1, = 1, < 1 as a measure for the affinity of the active agent to the mucus. The discussion of the kinetic parameters shows, as in previous results, no criterion for assuming specific mucus binding. Because of its unspecifity the usual term "mucus binding" should be replaced by "mucus retention".
Assuntos
Absorção Intestinal/fisiologia , Muco/fisiologia , Difusão , Modelos Biológicos , Pindolol/farmacocinética , SoftwareRESUMO
Drug level monitoring during routine clinical visits in the course of phase III trials provides a means to document pharmacokinetic variability in a patient population. Such a pharmacokinetic screen was performed for the new calcium antagonist isradipine. A total of 697 blood samples were collected at any time after the morning dose from 252 patients who had received oral doses of isradipine. Three approaches of data analysis based on exploratory (graphical and statistical) techniques were used to relate plasma level to patient demographic data and laboratory parameters. The pharamacokinetics of isradipine seemed to be influenced by the demographic variables of age (already detected in conventional studies) and weight, as well as by the blood serum levels of inorganic phosphorous, uric acid, alkaline phosphatase, and bilirubin, but only to a small, clinically irrelevant extent. The findings from the three approaches were complementary. They suggest that a pharmacokinetic screening in clinical trials is feasible at reasonable experimental cost and effort and provides useful data on interindividual and intraindividual pharmacokinetic variability in patients.
Assuntos
Bloqueadores dos Canais de Cálcio/farmacocinética , Piridinas/farmacocinética , Adulto , Idoso , Envelhecimento/metabolismo , Análise de Variância , Disponibilidade Biológica , Estatura , Peso Corporal , Bloqueadores dos Canais de Cálcio/sangue , Feminino , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Isradipino , Masculino , Pessoa de Meia-Idade , Piridinas/sangue , Fatores SexuaisRESUMO
A new radioimmunoassay (RIA) for the specific measurement of dihydroergotamine (DHE), sufficiently sensitive for the determination of low plasma concentrations, has been used to investigate the pharmacokinetics of unchanged DHE. In a randomized cross-over trial, eight healthy male volunteers received single doses of DHE 5 mg, 10 mg and 20 mg orally and 0.1 mg and 0.5 mg intravenously. It was possible to determine plasma concentrations and urinary excretion of DHE over the following 48 h. A long terminal plasma elimination phase of unchanged DHE (half-life 15 h) was found. A similar terminal elimination half-life was also calculated from urine data. The multi-exponential decline in plasma DHE with a long terminal half-life suggests that distribution into a deep compartment contributes to the long-lasting effect of the drug. Plasma protein binding was 93%. Despite extensive tissue distribution (Vz = 33 l/kg) and a high plasma clearance (CLP = 2 l/min), dose-independent linear pharmacokinetics was observed. The present assay was at least 20-times more specific than the polyvalent RIA used previously and appears suitable to explore the pharmacokinetics of unchanged DHE in patients on low-dose therapy. The long terminal elimination half-life of DHE only reported previously in studies using 3H-labelled drug, and considered to be due to metabolites, was also true for the parent compound. This, in addition to the sustained pharmacological activity of the 8'-hydroxy metabolite already shown, provides a further explanation for the long duration of action of DHE in animals and man.
Assuntos
Di-Hidroergotamina/farmacocinética , Administração Oral , Adulto , Di-Hidroergotamina/administração & dosagem , Di-Hidroergotamina/efeitos adversos , Meia-Vida , Humanos , Injeções Intravenosas , Masculino , Taxa de Depuração Metabólica , Ligação Proteica/efeitos dos fármacos , Radioimunoensaio , Distribuição TecidualRESUMO
Steady-state pharmacokinetic parameters of the new, long-acting beta-adrenoceptor blocker bopindolol have been measured in 17 young and 20 elderly healthy men. The t 1/2 beta and the AUC(0----24 h) of hydrolysed bopindolol (the active metabolite) were both increased (40% and 26%, respectively) in the elderly subjects but tmax, Cmax and CL/f were not altered. However, after adjusting the parameters to allow for the different average body weights of the two groups, Cmax and CL/f became significantly different (+29% and -30%, respectively). AUC(0----24 h) was increased by 41%. The changes of up to 41% in pharmacokinetic parameters were smaller than the alterations of 50-100% usually seen when titrating doses of antihypertensive drugs. The clinical relevance of the effects was not examined, but similar changes have been reported for other beta-blockers which did not appear to be clinically relevant and did not affect the dosage required to treat hypertension.
Assuntos
Antagonistas Adrenérgicos beta/farmacocinética , Envelhecimento/metabolismo , Pindolol/análogos & derivados , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Meia-Vida , Humanos , Hidrólise , Masculino , Pessoa de Meia-Idade , Pindolol/farmacocinética , Ensaio RadioliganteRESUMO
The pharmacokinetics of the dihydropyridine calcium antagonist isradipine has been examined in 8 healthy volunteers, 7 patients with non-cirrhotic chronic liver disease (CLD), and 8 patients with biopsy-proven cirrhosis (CIR). Isradipine was simultaneously given orally (12C 5 mg) and i.v. (13C 1 mg). Systemic availability was significantly increased from 17% to 16% in controls and CLD, respectively, to 37% in CIR. The corresponding systemic clearances averaged 1.1, 0.9 and 0.6 l.min-1, the reduction in cirrhotics being significant. Both aminopyrine demethylation capacity, a measure of hepatic microsomal function, and indocyanine green disappearance, a measure of hepatic perfusion, were correlated with the reduction in systemic clearance, and the reduction in oral clearance was correlated with the reciprocal of the serum bile acid concentration. The loss of first-pass extraction should be considered when this calcium antagonist is given perorally in patients with hepatic cirrhosis.
Assuntos
Hepatopatias/metabolismo , Piridinas/farmacocinética , Administração Oral , Adulto , Aminopirina/metabolismo , Ácidos e Sais Biliares/metabolismo , Biotransformação , Doença Crônica , Hepatite/metabolismo , Humanos , Verde de Indocianina , Injeções Intravenosas , Isradipino , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Modelos Biológicos , Piridinas/administração & dosagem , Piridinas/efeitos adversosRESUMO
The method of Loo and Riegelman is often used to calculate the relative amount absorbed as a function of time from plasma concentration data which follow a two-compartment open model. The method, however, is applicable only to single-dose data, whereas there is sometimes interest in the absorption-time profile at steady state after multiple doses. The method is modified here so that it can be applied to steady-state data and its use with a practical example is illustrated.
Assuntos
Farmacocinética , Pressão Sanguínea/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Humanos , Absorção Intestinal , Isradipino , Modelos Biológicos , Piridinas/farmacologia , Estatística como AssuntoRESUMO
1. DPI 201-106 (DPI) is a novel inotropic agent, with Na+ channel agonistic action combined with a sensitization of contractile proteins to Ca++. In a double-blind trial in healthy volunteers (n = 20) cardiovascular effects (blood pressure, heart rate, ECG) of single oral doses were studied. In addition systolic time intervals (STIs) were assessed in 10 of these subjects. DPI plasma concentrations were measured by h.p.l.c. 2. Preejection period was shortened by 14 ms (P less than 0.01) and 30 ms (P less than 0.01) 1 h after 30 and 60 mg, respectively, suggesting a dose-dependent inotropic effect. Heart rate was slightly reduced after both doses. Mean blood pressure remained unchanged. 3. Corrected QT interval duration (QTc) was prolonged by a mean of 7 ms (NS) and 22 ms (P less than 0.001) 1 h after 30 and 60 mg, respectively. PQ and QRS intervals remained unaffected. 4. Peak plasma levels were attained at 1-2 h and the terminal elimination half-life was approximately 15 h. 5. It is concluded that DPI has positive inotropic and negative chronotropic properties which make it potentially useful for the treatment of heart failure.
Assuntos
Eletrocardiografia , Frequência Cardíaca/efeitos dos fármacos , Piperazinas/farmacologia , Adulto , Pressão Sanguínea/efeitos dos fármacos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Hemodinâmica/efeitos dos fármacos , Humanos , Masculino , Piperazinas/farmacocinética , Distribuição AleatóriaRESUMO
The pharmacokinetics and the endocrine profile of a new low molecular somatostatin derivative, SMS 201-995, were investigated in a group of 35 normal subjects. Clearance studies (n = 6) for this peptide showed a prolonged half-life in plasma, 113 min, following single sc injections of 50 or 100 micrograms. Arginine stimulation tests (n = 6) were conducted immediately and 180 min after sc injection of 50 micrograms of SMS 201-995. The stimulatory effect of arginine on GH and insulin was counteracted by the peptide at the P less than 0.001 and P less than 0.02 significance level, respectively. Delayed arginine stimulation revealed a persistent blockade of the GH release (P less than 0.02), whereas a recovery of the insulin response was observed. Plasma glucagon increments following a standard protein meal (n = 10) were significantly (P less than 0.001) inhibited by previous sc injection of 50 micrograms of SMS 202-995. Pretreatment with 50 and 100 micrograms of SMS 202-995 sc (n = 9) inhibited (P less than 0.001) the stimulatory effect of TRH (200 micrograms iv) on TSH without modifying basal levels. The injection of 100 micrograms/h during sleep completely abolished the nocturnal GH peak in 4 volunteers. No rebound rise after decline of the suppressive action on GH was recorded in any of the trials. Safety chemistries and blood coagulation studies remained normal and no side-effects or untoward reactions were recorded throughout the investigation.(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Somatostatina/análogos & derivados , Adulto , Arginina/farmacologia , Glicemia/metabolismo , Proteínas Alimentares/administração & dosagem , Glucagon/sangue , Hormônio do Crescimento/sangue , Meia-Vida , Humanos , Injeções Subcutâneas , Insulina/sangue , Masculino , Octreotida , Sono/fisiologia , Somatostatina/administração & dosagem , Somatostatina/sangue , Tireotropina/metabolismo , Hormônio Liberador de Tireotropina/farmacologiaRESUMO
The pharmacokinetics of a new somatostatin derivative, SMS 201-995, was investigated in a group of eight healthy subjects. SMS 201-995 was given intravenously in doses of 25 micrograms, 50 micrograms, 100 micrograms, and 200 micrograms and also subcutaneously in doses of 50 micrograms, 100 micrograms, 200 micrograms, and 400 micrograms in accordance with a randomized Latin-square design. Blood samples were taken up to 8 h. The tolerability of SMS 201-995 was very good. Routine blood chemistry variables remained normal. After intravenous administration of SMS 201-995 initial half-lives ranging from 9 +/- 2 min to 14 +/- 4 min and second half-lives of from 72 +/- 22 min to 98 +/- 37 min were calculated for the different doses. SMS 201-995 was rapidly absorbed after subcutaneous injection with a half-life ranging from 5.3 +/- 2.2 min to 11.7 +/- 7.6 min. The disposition half-life was from 88 +/- 20 min to 102 +/- 16 min for the different doses. Cp(tmax) and AUC (0 - infinity) increased dose-dependently after both routes of administration, pointing to linear pharmacokinetics for SMS 201-995. On the basis of its good tolerability, slow plasma clearance, and long action, SMS 201-995 represents a valuable tool for further clinical studies.
Assuntos
Somatostatina/análogos & derivados , Adulto , Disponibilidade Biológica , Sistema Digestório/efeitos dos fármacos , Tolerância a Medicamentos , Feminino , Meia-Vida , Humanos , Injeções Intravenosas , Injeções Subcutâneas , Cinética , Masculino , Octreotida , Somatostatina/administração & dosagem , Somatostatina/efeitos adversos , Somatostatina/metabolismoRESUMO
Bopindolol, an esterified beta-adrenoceptor blocking drug, was administered to nine healthy male volunteers in oral (1 mg and 4 mg) and intravenous (1 mg) doses. Plasma concentrations determined using a radio-receptor assay (RRA) and high pressure liquid chromatography (h.p.l.c.) yielded almost identical results, indicating that hydrolysed bopindolol, the major metabolite, is responsible for the pharmacological activity of the drug. After intravenous administration the half-life for the formation of the hydrolysis product was about 0.3 h. The elimination of hydrolysed bopindolol from the plasma, determined with a one-compartment model occurred with a half-life of about 4 h. There were indications for a longer beta phase of elimination with a half-life of about 8 h, which, owing to the relative insensitivity of the method for concentrations present after more than 24 h, could not be determined exactly. The absolute bioavailability of the active compound is about 70%. Cardiac beta-adrenoceptor blockade was determined as the reduction in exercise-induced tachycardia. With oral doses the maximum effect was reached after 3 h (-29 beats min-1 after 1 mg, -40 beats min-1 after 4 mg). After intravenous administration most of the effect was present after 0.5 h but the maximum effect (-33 beats min-1) was only reached at 3 h. Bopindolol possesses a long duration of action: after 48 h 33% of the maximum effect of the oral dose of 4 mg was still present.(ABSTRACT TRUNCATED AT 250 WORDS)