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1.
Eur Urol ; 78(2): 184-192, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32273183

RESUMO

BACKGROUND: External beam radiotherapy (EBRT) with neoadjuvant/adjuvant androgen deprivation therapy (ADT) is an established treatment option to prolong survival for patients with intermediate- and high-risk prostate cancer (PCa). Relugolix, an oral gonadotropin-releasing hormone (GnRH) receptor antagonist, was evaluated in this clinical setting in comparison with degarelix, an injectable GnRH antagonist. OBJECTIVE: To evaluate the safety and efficacy of relugolix to achieve and maintain castration. DESIGN, SETTING, AND PARTICIPANTS: A phase 2 open-label study was conducted in 103 intermediate-risk PCa patients undergoing primary EBRT and neoadjuvant/adjuvant ADT between June 2014 and December 2015. INTERVENTION: Patients randomly assigned (3:2) to 24-wk treatment with either daily oral relugolix or 4-wk subcutaneous depot degarelix (reference control). OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary endpoint was the rate of effective castration (testosterone <1.73nmol/l) in relugolix patients between 4 and 24 wk of treatment. Secondary endpoints included rate of profound castration (testosterone <0.7nmol/l), prostate-specific antigen (PSA) levels, prostate volume, quality of life (QoL) assessed using the Aging Males' Symptoms scale, and the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life (30-item EORTC core questionnaire [EORTC QLQ-C30] and 25-item EORTC prostate cancer module [EORTC QLQ-PR25]) questionnaires, and safety. No formal statistical comparisons with degarelix were planned. RESULTS AND LIMITATIONS: Castration rates during treatment were 95% and 82% with relugolix and 89% and 68% with degarelix for 1.73 and 0.7nmol/l thresholds, respectively. Median time to castration in the relugolix arm was 4 d. During treatment, PSA levels and prostate volumes were reduced in both groups. Three months after discontinuing treatment, 52% of men on relugolix and 16% on degarelix experienced testosterone recovery (statistical significance of differences not tested). Mean and median QoL scores improved following treatment discontinuation. The most common adverse event was hot flush (relugolix 57%; degarelix 61%). Lack of blinding was a potential limitation. CONCLUSIONS: Relugolix achieved testosterone suppression to castrate levels within days and maintained it over 24 wk with a safety profile consistent with its mechanism of action. PATIENT SUMMARY: Oral once-daily relugolix may be a novel oral alternative to injectable androgen deprivation therapies.


Assuntos
Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Compostos de Fenilureia/administração & dosagem , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/radioterapia , Pirimidinonas/administração & dosagem , Administração Oral , Idoso , Humanos , Masculino , Terapia Neoadjuvante , Neoplasias da Próstata/patologia , Medição de Risco
2.
Clin Pharmacol Drug Dev ; 5(3): 188-95, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27163497

RESUMO

This study aimed to determine the impact of food on the pharmacokinetics of orteronel, an investigational nonsteroidal, reversible selective inhibitor of 17,20-lyase. In this open-label, randomized crossover study, healthy subjects received single doses of orteronel 400 mg with a low-fat meal, a high-fat meal, and under fasting conditions in a randomized sequence. Plasma concentrations of orteronel and its primary M-I metabolite were determined by ultra-performance liquid chromatography, and pharmacokinetic parameters were evaluated using mixed-effects analysis of variance model. Compared with fasting conditions, the oral bioavailability of orteronel was increased under fed conditions. The least-squares mean ratio for area under the plasma concentration-time curve after a low-fat breakfast was 135% (90% confidence interval [CI], 126%-145%) compared with fasting conditions. Similarly, after a high-fat breakfast, the corresponding value was 142% (90%CI, 132%-152%). No unexpected safety concerns were raised with orteronel 400 mg administered in the fasted state or after either a high-fat or a low-fat meal; mild adverse events were experienced by 36% of the healthy male subjects.


Assuntos
Inibidores das Enzimas do Citocromo P-450/administração & dosagem , Interações Alimento-Droga , Imidazóis/administração & dosagem , Naftalenos/administração & dosagem , Administração Oral , Adolescente , Adulto , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Inibidores das Enzimas do Citocromo P-450/efeitos adversos , Inibidores das Enzimas do Citocromo P-450/farmacocinética , Gorduras na Dieta , Jejum , Humanos , Imidazóis/efeitos adversos , Imidazóis/farmacocinética , Análise dos Mínimos Quadrados , Masculino , Pessoa de Meia-Idade , Naftalenos/efeitos adversos , Naftalenos/farmacocinética , Esteroide 17-alfa-Hidroxilase/antagonistas & inibidores , Adulto Jovem
3.
J Clin Endocrinol Metab ; 100(12): 4579-87, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26502357

RESUMO

CONTEXT: TAK-385 is a highly selective, oral, nonpeptide GnRH antagonist being investigated as a possible prostate cancer treatment. OBJECTIVE: The objectives were to evaluate safety, tolerability, pharmacokinetics, and pharmacodynamics of TAK-385 on LH and testosterone. DESIGN, SETTING, AND PARTICIPANTS: This was a three-part, randomized, double-blind, placebo-controlled, phase 1 dose-escalation study in 176 healthy male UK volunteers. INTERVENTIONS: Part 1, single doses of TAK-385 (0 [placebo], 80, 120, 180, or 360 mg). Part 2, 14-day TAK-385 (0, 20, 40, 80, or 180 mg) daily. Part 3, 28-day TAK-385 (40 [with loading dose], 60, 80, or 160 mg) or placebo daily. Parts 2 and 3 included men aged 40-75 years. MAIN OUTCOME MEASURES: Main outcome measures included plasma concentrations of TAK-385, LH, and testosterone. RESULTS: Oral TAK-385 was readily absorbed, and steady state was reached in ≤ 14 days. Food reduced TAK-385 systemic exposure by 47-52%. Mean serum testosterone levels declined ≤ 6 hours after TAK-385 administration. Loading doses up to 360 mg on day 1 or 360 mg on day 1 followed by 240 mg on day 2 reduced the time to achieve castrate testosterone levels from ≥ 7 to <3 days. TAK-385 doses ≥ 80 mg/d achieved sustained medical castration and trough TAK-385 concentrations >4 ng/mL. After discontinuation of TAK-385 on day 28, testosterone levels normalized in most subjects in ≤ 28 days. Common adverse events included bradycardia, headache, and hot flush (all grade ≤ 2). CONCLUSIONS: Oral TAK-385 (40-180 mg/d) was well tolerated and effectively lowered testosterone in healthy men. Planned phase 2 doses in men with hormone-sensitive prostate cancer are 80 and 120 mg/d.


Assuntos
Castração/métodos , Hormônio Liberador de Gonadotropina/antagonistas & inibidores , Compostos de Fenilureia/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Pirimidinonas/uso terapêutico , Adulto , Idoso , Relação Dose-Resposta a Droga , Método Duplo-Cego , Interações Alimento-Droga , Humanos , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Compostos de Fenilureia/efeitos adversos , Compostos de Fenilureia/farmacocinética , Pirimidinonas/efeitos adversos , Pirimidinonas/farmacocinética , Testosterona/sangue , Resultado do Tratamento , Adulto Jovem
4.
Lancet Oncol ; 16(3): 338-48, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25701170

RESUMO

BACKGROUND: Orteronel is an investigational, partially selective inhibitor of CYP 17,20-lyase in the androgen signalling pathway, a validated therapeutic target for metastatic castration-resistant prostate cancer. We assessed orteronel in chemotherapy-naive patients with metastatic castration-resistant prostate cancer. METHODS: In this phase 3, double-blind, placebo-controlled trial, we recruited patients with progressive metastatic castration-resistant prostate cancer and no previous chemotherapy from 324 study centres (ie, hospitals or large urologic or group outpatient offices) in 43 countries. Eligible patients were randomly assigned in a 1:1 ratio to receive either 400 mg orteronel plus 5 mg prednisone twice daily or placebo plus 5 mg prednisone twice daily. Randomisation was done centrally with an interactive voice response system and patients were stratified by region (Europe, North America, and not Europe or North America) and the presence or absence of radiographic disease progression at baseline. The two primary endpoints were radiographic progression-free survival and overall survival, determined in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT01193244. FINDINGS: From Oct 31, 2010, to June 29, 2012, 2353 patients were assessed for eligibility. Of those, 1560 were randomly assigned to receive either orteronel plus prednisone (n=781) or placebo plus prednisone (n=779). The clinical cutoff date for the final analysis was Jan 15, 2014 (with 611 deaths). Median follow-up for radiographic progression-free survival was 8·4 months (IQR 3·7-16·6). Median radiographic progression-free survival was 13·8 months (95% CI 13·1-14·9) with orteronel plus prednisone and 8·7 months (8·3-10·9) with placebo plus prednisone (hazard ratio [HR] 0·71, 95% CI 0·63-0·80; p<0·0001). After a median follow-up of 20·7 months (IQR 14·2-25·4), median overall survival was 31·4 months (95% CI 28·6-not estimable) with orteronel plus prednisone and 29·5 months (27·0-not estimable) with placebo plus prednisone (HR 0·92, 95% CI 0·79-1·08; p=0·31). The most common grade 3 or worse adverse events were increased lipase (137 [17%] of 784 patients in the orteronel plus prednisone group vs 14 [2%] of 770 patients in the placebo plus prednisone group), increased amylase (77 [10%] vs nine [1%]), fatigue (50 [6%] vs 14 [2%]), and pulmonary embolism (40 [5%] vs 27 [4%]). Serious adverse events were reported in 358 [46%] patients receiving orteronel plus prednisone and in 292 [38%] patients receiving placebo plus prednisone. INTERPRETATION: In chemotherapy-naive patients with metastatic castration-resistant prostate cancer, radiographic progression-free survival was prolonged with orteronel plus prednisone versus placebo plus prednisone. However, no improvement was noted in the other primary endpoint, overall survival. Orteronel plus prednisone was associated with increased toxic effects compared with placebo plus prednisone. On the basis of these and other data, orteronel is not undergoing further development in metastatic castration-resistant prostate cancer. FUNDING: Millennium Pharmaceuticals, Inc, a wholly owned subsidiary of Takeda Pharmaceutical Company Limited.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias de Próstata Resistentes à Castração/tratamento farmacológico , Adenocarcinoma/enzimologia , Adenocarcinoma/mortalidade , Adenocarcinoma/secundário , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Ásia , Austrália , Inibidores das Enzimas do Citocromo P-450/administração & dosagem , Progressão da Doença , Intervalo Livre de Doença , Método Duplo-Cego , Europa (Continente) , Humanos , Imidazóis/administração & dosagem , Análise de Intenção de Tratamento , Estimativa de Kaplan-Meier , Masculino , Naftalenos/administração & dosagem , Nova Zelândia , América do Norte , Prednisona/administração & dosagem , Modelos de Riscos Proporcionais , Neoplasias de Próstata Resistentes à Castração/enzimologia , Neoplasias de Próstata Resistentes à Castração/mortalidade , Neoplasias de Próstata Resistentes à Castração/patologia , Fatores de Risco , Esteroide 17-alfa-Hidroxilase/antagonistas & inibidores , Esteroide 17-alfa-Hidroxilase/metabolismo , Fatores de Tempo , Resultado do Tratamento
5.
J Clin Endocrinol Metab ; 99(8): E1445-53, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24762108

RESUMO

BACKGROUND/OBJECTIVE: Kisspeptin-54, an endogenous naturally occurring ligand of the G protein-coupled receptor-54, stimulates GnRH-gonadotropin secretion and suppresses metastases in animal models of cancer but is subject to rapid degradation and inactivation. TAK-448 is an investigational oligopeptide analog of the fully active 10-amino acid C terminus of kisspeptin-54. This phase 1 study evaluated the safety, pharmacokinetics, and pharmacodynamics of TAK-448 in healthy subjects and patients with prostate cancer (PC). DESIGN: Healthy subjects aged 50 years or older received TAK-448 sc as a single-bolus or 2-hour infusion (0.01-6 mg/d; part A) and as a 14-day sc administration (0.01-1 mg/d; part B). In a subsequent, open-label, phase 1 study in PC patients aged 40-78 years, TAK-448 was given as a 1-month depot formulation. RESULTS: Eighty-two healthy subjects received TAK-448; 30 received placebo. Grades 1-2 adverse events were reported in 26% of subjects during TAK-448 treatment. All dosing regimens resulted in dose-proportional exposures. The maximum observed plasma concentration occurred after 0.25-0.5 hours, and median terminal elimination half-life was 1.4-5.3 hours. T increased approximately 1.3- to 2-fold by 48 hours after a single bolus or 2 hour injections, whereas during the 14-day infusion, at doses above 0.1 mg/d, T dropped to below-baseline values by 60 hours and reached a subsequently sustained below-castration level by day 8. In PC patients, T decreased to less than 20 ng/dL in four of five patients dosed with 12 or 24 mg TAK-448 sc-depot injections. The prostate-specific antigen decreased greater than 50% in all patients dosed with 24 mg. CONCLUSIONS: Continuous TAK-448 infusion was well tolerated by healthy males and resulted in sustained T suppression. Depot injection in patients with PC similarly reduced T and resulted in prostate-specific antigen responses.


Assuntos
Drogas em Investigação/administração & dosagem , Kisspeptinas/administração & dosagem , Orquiectomia , Neoplasias da Próstata/sangue , Testosterona/sangue , Adulto , Idoso , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Esquema de Medicação , Drogas em Investigação/efeitos adversos , Drogas em Investigação/farmacocinética , Saúde , Humanos , Kisspeptinas/efeitos adversos , Kisspeptinas/farmacocinética , Hormônio Luteinizante/sangue , Masculino , Pessoa de Meia-Idade , Placebos , Neoplasias da Próstata/metabolismo
6.
Stroke ; 42(6): 1631-7, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21493908

RESUMO

BACKGROUND AND PURPOSE: Chronic deficiencies in regional blood flow lead to cerebral cortical thinning without evidence of gross tissue loss at the same time as potentially negatively impacting on neurological and cognitive performance. This is most pronounced in patients with severe occlusive cerebrovascular disease in whom affected brain areas exhibit "steal physiology," a paradoxical reduction of cerebral blood flow in response to a global vasodilatory stimulus intended to increase blood flow. We tested whether surgical brain revascularization that eliminates steal physiology can reverse cortical thinning. METHODS: We identified 29 patients from our database who had undergone brain revascularization with pre- and postoperative studies of cerebrovascular reactivity using blood oxygen(ation) level-dependent MRI and whose preoperative study exhibited steal physiology without MRI-evident structural abnormalities. Cortical thickness in regions corresponding to steal physiology, and where applicable corresponding areas in the normal hemisphere, were measured using Freesurfer software. RESULTS: At an average of 11 months after surgery, cortical thickness increased in every successfully revascularized hemisphere (n=30). Mean cortical thickness in the revascularized regions increased by 5.1% (from 2.40 ± 0.03 to 2.53 ± 0.03; P<0.0001). CONCLUSIONS: Successful regional revascularization and reversal of steal physiology is followed by restoration of cortical thickness.


Assuntos
Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/patologia , Córtex Cerebral/cirurgia , Revascularização Cerebral/métodos , Circulação Cerebrovascular/fisiologia , Transtornos Cerebrovasculares/patologia , Adolescente , Adulto , Idoso , Córtex Cerebral/fisiopatologia , Transtornos Cerebrovasculares/fisiopatologia , Feminino , Hemodinâmica , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Fluxo Sanguíneo Regional , Adulto Jovem
7.
Brain Res ; 1020(1-2): 1-11, 2004 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-15312781

RESUMO

A steroidal glycoside with anorectic activity in animals, termed P57AS3 (P57), was isolated from Hoodia gordonii and found to have homologies to the steroidal core of cardiac glycosides. Intracerebroventricular (i.c.v.) injections of the purified P57AS3 demonstrated that the compound has a likely central (CNS) mechanism of action. There is no evidence of P57AS3 binding to or altering activity of known receptors or proteins, including Na/K-ATPase, the putative target of cardiac glycosides. The studies demonstrated that the compound increases the content of ATP by 50-150% in hypothalamic neurons. In addition, third ventricle (i.c.v.) administration of P57, which reduces subsequent 24-h food intake by 40-60%, also increases ATP content in hypothalamic slice punches removed at 24 h following the i.c.v. injections. In related studies, in pair fed rats fed a low calorie diet for 4 days, the content of ATP in the hypothalami of control i.c.v. injected animals fell by 30-50%, which was blocked by i.c.v. injections of P57AS3. With growing evidence of metabolic or nutrient-sensing by the hypothalamus, ATP may be a common currency of energy sensing, which in turn may trigger the appropriate neural, endocrine and appetitive responses as similar to other fundamental hypothalamic homeostatic centers for temperature and osmolarity.


Assuntos
Trifosfato de Adenosina/metabolismo , Depressores do Apetite/farmacologia , Regulação do Apetite/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Glicosídeos/farmacologia , Hipotálamo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Esteroides/farmacologia , Animais , Anorexia/induzido quimicamente , Regulação do Apetite/fisiologia , Células Cultivadas , Relação Dose-Resposta a Droga , Metabolismo Energético/fisiologia , Privação de Alimentos/fisiologia , Hipotálamo/citologia , Hipotálamo/metabolismo , Injeções Intraventriculares , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Resposta de Saciedade/efeitos dos fármacos , Resposta de Saciedade/fisiologia
8.
Brain Res ; 973(2): 233-9, 2003 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-12738067

RESUMO

The effects of thyroid hormone on whole body energy metabolism and compensatory effects on food intake are well established. However, the hypothalamic mechanisms that translate perceived whole body energy demands into subsequent appetitive behavior are incompletely understood. In order to address this question, we tested the effects of T3 on food intake and body weight in rats and measured neuronal Na/K ATPase activity and ATP content in the hypothalamus. Intraperitoneal T3 (100 microg/kg BW) administered for 6 consecutive days increased 24-h rat food intake from control, 26.6+/-1.2, to T3-treated 33.2+/-1.6 g (P<0.01). In T3-treated rats, rubidium-86 (86Rb) uptake (measured as a marker of Na/K ATPase activity) in ex vivo hypothalamic tissue increased (P<0.01) while the content of ATP in the ventral hypothalamus declined following T3 treatment (P<0.01). In another model of energy deficit, which was induced by a very low calorie diet, ATP content was also reduced in the hypothalamus compared to rats fed ad libitum. In summary, increased food intake in response to T3 may be secondary to decreased hypothalamic ATP content, perhaps resulting from both increased Na/K ATPase activity in the hypothalamus and metabolic signaling induced by whole body caloric deficit.


Assuntos
Trifosfato de Adenosina/análise , Ingestão de Alimentos/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , ATPase Trocadora de Sódio-Potássio/metabolismo , Hormônios Tireóideos/farmacologia , Tri-Iodotironina Reversa/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Comportamento Animal , Peso Corporal/efeitos dos fármacos , Cerebelo/metabolismo , Córtex Cerebral/metabolismo , Dieta , Relação Dose-Resposta a Droga , Hipotálamo/enzimologia , Hipotálamo/metabolismo , Técnicas In Vitro , Fígado/metabolismo , Masculino , Ratos , Ratos Endogâmicos , Radioisótopos de Rubídio/metabolismo , Hormônios Tireóideos/administração & dosagem , Fatores de Tempo , Tri-Iodotironina Reversa/administração & dosagem
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