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1.
Nephrol Dial Transplant ; 38(8): 1890-1897, 2023 07 31.
Artigo em Inglês | MEDLINE | ID: mdl-36565721

RESUMO

BACKGROUND: The prespecified on-treatment analysis of ASCEND-ND (NCT02876835) raised concerns about a higher relative risk of cancer-related adverse events (AEs) with daprodustat vs darbepoetin in patients with anaemia of CKD. This concern was not observed in dialysis patients in ASCEND-D (NCT02879305). METHODS: ASCEND-ND randomized 3872 patients to daprodustat or darbepoetin. ASCEND-D randomized 2964 patients to daprodustat or conventional erythropoiesis-stimulating agents (ESAs). In both studies ESA comparators used different dosing intervals (3/week, 1/week, every 2 or every 4 weeks). The prespecified on-treatment approach examined relative risks for cancer AEs up to the last dose date + 1 day. In these analyses, owing to different dosing intervals between arms, Cox models were used to estimate the daprodustat effect by various follow-up periods (censoring at last dose date, last dose date + dosing intervals, or end of study). RESULTS: In ASCEND-ND, the safety of daprodustat vs darbepoetin on cancer-related AEs depended on the duration of follow-up after last dose date: hazard ratio (HR) 1.04 [95% confidence interval (CI) 0.77, 1.40] at end of study [HR 1.12 (95% CI 0.81, 1.56) for last dose date + dosing interval; HR 1.50 (95% CI 1.04, 2.15) for last dose date + 1 day]. In ASCEND-D, no excess risk of cancer-related AEs was observed with any model examined. CONCLUSIONS: Prespecified on-treatment analyses for cancer-related AEs appeared to result in biased risk estimates in ASCEND-ND by preferentially under-counting events from patients assigned to darbepoetin. Analyses accounting for longer darbepoetin dosing intervals, or extending follow-up, resulted in attenuation of effect estimates towards neutrality, similar to ASCEND-D, where ESA comparator dosing intervals are closer to daprodustat. TRIAL REGISTRATION: The ASCEND-ND trial is registered with ClinicalTrials.gov (NCT02876835); the ASCEND-D trial is registered with ClinicalTrials.gov (NCT02879305).


Assuntos
Eritropoetina , Hematínicos , Neoplasias , Insuficiência Renal Crônica , Humanos , Hematínicos/efeitos adversos , Eritropoetina/efeitos adversos , Eritropoese , Diálise Renal , Darbepoetina alfa/efeitos adversos , Neoplasias/complicações , Neoplasias/epidemiologia , Neoplasias/induzido quimicamente , Insuficiência Renal Crônica/tratamento farmacológico , Hemoglobinas
2.
N Engl J Med ; 384(17): 1601-1612, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33913638

RESUMO

BACKGROUND: Vadadustat is an oral hypoxia-inducible factor prolyl hydroxylase inhibitor, a class of compounds that stimulate endogenous erythropoietin production. METHODS: We conducted two randomized, open-label, noninferiority phase 3 trials to evaluate the safety and efficacy of vadadustat, as compared with darbepoetin alfa, in patients with anemia and incident or prevalent dialysis-dependent chronic kidney disease (DD-CKD). The primary safety end point, assessed in a time-to-event analysis, was the first occurrence of a major adverse cardiovascular event (MACE, a composite of death from any cause, a nonfatal myocardial infarction, or a nonfatal stroke), pooled across the trials (noninferiority margin, 1.25). A key secondary safety end point was the first occurrence of a MACE plus hospitalization for either heart failure or a thromboembolic event. The primary and key secondary efficacy end points were the mean change in hemoglobin from baseline to weeks 24 to 36 and from baseline to weeks 40 to 52, respectively, in each trial (noninferiority margin, -0.75 g per deciliter). RESULTS: A total of 3923 patients were randomly assigned in a 1:1 ratio to receive vadadustat or darbepoetin alfa: 369 in the incident DD-CKD trial and 3554 in the prevalent DD-CKD trial. In the pooled analysis, a first MACE occurred in 355 patients (18.2%) in the vadadustat group and in 377 patients (19.3%) in the darbepoetin alfa group (hazard ratio, 0.96; 95% confidence interval [CI], 0.83 to 1.11). The mean differences between the groups in the change in hemoglobin concentration were -0.31 g per deciliter (95% CI, -0.53 to -0.10) at weeks 24 to 36 and -0.07 g per deciliter (95% CI, -0.34 to 0.19) at weeks 40 to 52 in the incident DD-CKD trial and -0.17 g per deciliter (95% CI, -0.23 to -0.10) and -0.18 g per deciliter (95% CI, -0.25 to -0.12), respectively, in the prevalent DD-CKD trial. The incidence of serious adverse events in the vadadustat group was 49.7% in the incident DD-CKD trial and 55.0% in the prevalent DD-CKD trial, and the incidences in the darbepoetin alfa group were 56.5% and 58.3%, respectively. CONCLUSIONS: Among patients with anemia and CKD who were undergoing dialysis, vadadustat was noninferior to darbepoetin alfa with respect to cardiovascular safety and correction and maintenance of hemoglobin concentrations. (Funded by Akebia Therapeutics and Otsuka Pharmaceutical; INNO2VATE ClinicalTrials.gov numbers, NCT02865850 and NCT02892149.).


Assuntos
Anemia/tratamento farmacológico , Darbepoetina alfa/uso terapêutico , Glicina/análogos & derivados , Hematínicos/uso terapêutico , Ácidos Picolínicos/uso terapêutico , Inibidores de Prolil-Hidrolase/uso terapêutico , Diálise Renal/efeitos adversos , Insuficiência Renal Crônica/complicações , Idoso , Anemia/sangue , Anemia/etiologia , Doenças Cardiovasculares/induzido quimicamente , Darbepoetina alfa/efeitos adversos , Feminino , Glicina/efeitos adversos , Glicina/uso terapêutico , Hematínicos/efeitos adversos , Hemoglobinas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Ácidos Picolínicos/efeitos adversos , Inibidores de Prolil-Hidrolase/efeitos adversos , Insuficiência Renal Crônica/mortalidade , Insuficiência Renal Crônica/terapia
3.
N Engl J Med ; 384(17): 1589-1600, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33913637

RESUMO

BACKGROUND: Vadadustat is an oral hypoxia-inducible factor (HIF) prolyl hydroxylase inhibitor, a class of drugs that stabilize HIF and stimulate erythropoietin and red-cell production. METHODS: In two phase 3, randomized, open-label, active-controlled, noninferiority trials, we compared vadadustat with the erythropoiesis-stimulating agent (ESA) darbepoetin alfa in patients with non-dialysis-dependent chronic kidney disease (NDD-CKD) not previously treated with an ESA who had a hemoglobin concentration of less than 10 g per deciliter and in patients with ESA-treated NDD-CKD and a hemoglobin concentration of 8 to 11 g per deciliter (in the United States) or 9 to 12 g per deciliter (in other countries). The primary safety end point, assessed in a time-to-event analysis, was the first major adverse cardiovascular event (MACE; a composite of death from any cause, nonfatal myocardial infarction, or nonfatal stroke), pooled across the two trials. Secondary safety end points included expanded MACE (MACE plus hospitalization for either heart failure or a thromboembolic event). The primary and key secondary efficacy end points in each trial were the mean change in hemoglobin concentration from baseline during two evaluation periods: weeks 24 through 36 and weeks 40 through 52. RESULTS: A total of 1751 patients with ESA-untreated NDD-CKD and 1725 with ESA-treated NDD-CKD underwent randomization in the two trials. In the pooled analysis, in which 1739 patients received vadadustat and 1732 received darbepoetin alfa, the hazard ratio for MACE was 1.17 (95% confidence interval [CI], 1.01 to 1.36), which did not meet the prespecified noninferiority margin of 1.25. The mean between-group differences in the change in the hemoglobin concentration at weeks 24 through 36 were 0.05 g per deciliter (95% CI, -0.04 to 0.15) in the trial involving ESA-untreated patients and -0.01 g per deciliter (95% CI, -0.09 to 0.07) in the trial involving ESA-treated patients, which met the prespecified noninferiority margin of -0.75 g per deciliter. CONCLUSIONS: Vadadustat, as compared with darbepoetin alfa, met the prespecified noninferiority criterion for hematologic efficacy but not the prespecified noninferiority criterion for cardiovascular safety in patients with NDD-CKD. (Funded by Akebia Therapeutics and Otsuka Pharmaceutical; PRO2TECT ClinicalTrials.gov numbers, NCT02648347 and NCT02680574.).


Assuntos
Anemia/tratamento farmacológico , Darbepoetina alfa/uso terapêutico , Glicina/análogos & derivados , Hematínicos/uso terapêutico , Ácidos Picolínicos/uso terapêutico , Inibidores de Prolil-Hidrolase/uso terapêutico , Insuficiência Renal Crônica/complicações , Administração Oral , Idoso , Anemia/sangue , Anemia/etiologia , Doenças Cardiovasculares/induzido quimicamente , Darbepoetina alfa/efeitos adversos , Feminino , Glicina/efeitos adversos , Glicina/uso terapêutico , Hematínicos/efeitos adversos , Hemoglobinas/análise , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Ácidos Picolínicos/efeitos adversos , Inibidores de Prolil-Hidrolase/efeitos adversos , Insuficiência Renal Crônica/mortalidade
4.
Ophthalmology ; 126(9): 1273-1285, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31443789

RESUMO

PURPOSE: To report the durability of voretigene neparvovec-rzyl (VN) adeno-associated viral vector-based gene therapy for RPE65 mutation-associated inherited retinal dystrophy (IRD), including results of a phase 1 follow-on study at year 4 and phase 3 study at year 2. DESIGN: Open-label phase 1 follow-on clinical trial and open-label, randomized, controlled phase 3 clinical trial. PARTICIPANTS: Forty subjects who received 1.5×1011 vector genomes (vg) of VN per eye in at least 1 eye during the trials, including 11 phase 1 follow-on subjects and 29 phase 3 subjects (20 original intervention [OI] and 9 control/intervention [CI]). METHODS: Subretinal injection of VN in the second eye of phase 1 follow-on subjects and in both eyes of phase 3 subjects. MAIN OUTCOME MEASURES: End points common to the phase 1 and phase 3 studies included change in performance on the Multi-Luminance Mobility Test (MLMT) within the illuminance range evaluated, full-field light sensitivity threshold (FST) testing, and best-corrected visual acuity (BCVA). Safety end points included adverse event reporting, ophthalmic examination, physical examination, and laboratory testing. RESULTS: Mean (standard deviation) MLMT lux score change was 2.4 (1.3) at 4 years compared with 2.6 (1.6) at 1 year after administration in phase 1 follow-on subjects (n = 8), 1.9 (1.1) at 2 years, and 1.9 (1.0) at 1 year post-administration in OI subjects (n = 20), and 2.1 (1.6) at 1 year post-administration in CI subjects (n = 9). All 3 groups maintained an average improvement in FST, reflecting more than a 2 log10(cd.s/m2) improvement in light sensitivity at 1 year and subsequent available follow-up visits. The safety profile was consistent with vitrectomy and the subretinal injection procedure, and no deleterious immune responses occurred. CONCLUSIONS: After VN gene augmentation therapy, there was a favorable benefit-to-risk profile with similar improvement demonstrated in navigational ability and light sensitivity among 3 groups of subjects with RPE65 mutation-associated IRD, a degenerative disease that progresses to complete blindness. The safety profile is consistent with the administration procedure. These data suggest that this effect, which is nearly maximal by 30 days after VN administration, is durable for 4 years, with observation ongoing.


Assuntos
Dependovirus/genética , Terapia Genética/métodos , Vetores Genéticos , Mutação , Distrofias Retinianas/terapia , cis-trans-Isomerases/genética , Adolescente , Adulto , Criança , Feminino , Seguimentos , Humanos , Masculino , Atividade Motora/fisiologia , Desempenho Psicomotor , Distrofias Retinianas/genética , Distrofias Retinianas/fisiopatologia , Limiar Sensorial , Resultado do Tratamento , Baixa Visão/fisiopatologia , Visão Ocular , Acuidade Visual/fisiologia , Testes de Campo Visual , Campos Visuais/fisiologia , Adulto Jovem
5.
Lancet ; 390(10097): 849-860, 2017 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-28712537

RESUMO

BACKGROUND: Phase 1 studies have shown potential benefit of gene replacement in RPE65-mediated inherited retinal dystrophy. This phase 3 study assessed the efficacy and safety of voretigene neparvovec in participants whose inherited retinal dystrophy would otherwise progress to complete blindness. METHODS: In this open-label, randomised, controlled phase 3 trial done at two sites in the USA, individuals aged 3 years or older with, in each eye, best corrected visual acuity of 20/60 or worse, or visual field less than 20 degrees in any meridian, or both, with confirmed genetic diagnosis of biallelic RPE65 mutations, sufficient viable retina, and ability to perform standardised multi-luminance mobility testing (MLMT) within the luminance range evaluated, were eligible. Participants were randomly assigned (2:1) to intervention or control using a permuted block design, stratified by age (<10 years and ≥10 years) and baseline mobility testing passing level (pass at ≥125 lux vs <125 lux). Graders assessing primary outcome were masked to treatment group. Intervention was bilateral, subretinal injection of 1·5 × 1011 vector genomes of voretigene neparvovec in 0·3 mL total volume. The primary efficacy endpoint was 1-year change in MLMT performance, measuring functional vision at specified light levels. The intention-to-treat (ITT) and modified ITT populations were included in primary and safety analyses. This trial is registered with ClinicalTrials.gov, number NCT00999609, and enrolment is complete. FINDINGS: Between Nov 15, 2012, and Nov 21, 2013, 31 individuals were enrolled and randomly assigned to intervention (n=21) or control (n=10). One participant from each group withdrew after consent, before intervention, leaving an mITT population of 20 intervention and nine control participants. At 1 year, mean bilateral MLMT change score was 1·8 (SD 1·1) light levels in the intervention group versus 0·2 (1·0) in the control group (difference of 1·6, 95% CI 0·72-2·41, p=0·0013). 13 (65%) of 20 intervention participants, but no control participants, passed MLMT at the lowest luminance level tested (1 lux), demonstrating maximum possible improvement. No product-related serious adverse events or deleterious immune responses occurred. Two intervention participants, one with a pre-existing complex seizure disorder and another who experienced oral surgery complications, had serious adverse events unrelated to study participation. Most ocular events were mild in severity. INTERPRETATION: Voretigene neparvovec gene replacement improved functional vision in RPE65-mediated inherited retinal dystrophy previously medically untreatable. FUNDING: Spark Therapeutics.


Assuntos
Terapia Genética/métodos , Distrofias Retinianas/terapia , cis-trans-Isomerases/genética , Adolescente , Feminino , Vetores Genéticos , Humanos , Masculino , Mutação/genética , Distrofias Retinianas/genética , Resultado do Tratamento , Estados Unidos
6.
Ophthalmology ; 123(6): 1287-96, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27086023

RESUMO

PURPOSE: To assess the safety and efficacy of epimacular brachytherapy (EMB) for patients with chronic, active, neovascular age-related macular degeneration (AMD). DESIGN: Phase 3 randomized controlled trial. PARTICIPANTS: Patients (n = 363) with neovascular AMD already receiving intravitreal ranibizumab injections. INTERVENTION: Either pars plana vitrectomy with 24-gray EMB and ongoing pro re nata (PRN) ranibizumab (n = 224) or ongoing PRN ranibizumab monotherapy (n = 119). MAIN OUTCOME MEASURES: The coprimary outcomes, at 12 months, were the number of PRN ranibizumab injections and Early Treatment of Diabetic Retinopathy Study (ETDRS) best-corrected visual acuity (VA). Secondary outcomes included the proportion of participants losing fewer than 15 ETDRS letters, angiographic total lesion size, choroidal neovascularization (CNV) size, and optical coherence tomography (OCT) foveal thickness. A predefined subgroup analysis tested the influence of baseline ocular characteristics on the response to EMB. RESULTS: The mean number of PRN ranibizumab injections was 4.8 in the EMB arm and 4.1 in the ranibizumab monotherapy arm (P = 0.068). The mean VA change was -4.8 letters in the EMB arm and -0.9 letters in the ranibizumab arm (95% confidence interval of difference between groups, -6.6 to -1.8 letters). The proportion of participants losing fewer than 15 letters was 84% in the EMB arm and 92% in the ranibizumab arm (P = 0.007). In the EMB arm, the mean total lesion size increased by 1.2 mm(2) versus 0.4 mm(2) in the ranibizumab arm (P = 0.27). The CNV size decreased by 0.5 mm(2) in the EMB arm and by 1.3 mm(2) in the ranibizumab arm (P = 0.27). The OCT foveal thickness decreased by 1.0 µm in the EMB arm and by 15.7 µm in the ranibizumab arm (P = 0.43). Most subgroups favored ranibizumab monotherapy, some significantly so. One participant showed retinal vascular abnormality attributed to radiation, but otherwise safety was acceptable. CONCLUSIONS: These results do not support the use of EMB for chronic, active, neovascular AMD. Safety is acceptable out to 12 months, but radiation retinopathy can occur later, so further follow-up is planned.


Assuntos
Braquiterapia/métodos , Radioisótopos de Estrôncio/uso terapêutico , Degeneração Macular Exsudativa/radioterapia , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/uso terapêutico , Braquiterapia/efeitos adversos , Doença Crônica , Feminino , Angiofluoresceinografia , Humanos , Injeções Intravítreas , Macula Lutea , Masculino , Pessoa de Meia-Idade , Lesões por Radiação/etiologia , Ranibizumab/uso terapêutico , Retina/efeitos da radiação , Terapia de Salvação , Radioisótopos de Estrôncio/efeitos adversos , Tomografia de Coerência Óptica , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Vitrectomia , Degeneração Macular Exsudativa/diagnóstico , Degeneração Macular Exsudativa/tratamento farmacológico
7.
Curr Opin Urol ; 25(5): 395-401, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26148069

RESUMO

PURPOSE OF REVIEW: In patients with metastatic renal cell carcinoma and favourable or intermediate risk, sunitinib, pazopanib, and bevacizumab along with interferon have been recommended with identical evidence level I, recommendation grade A. In clinical practice, most physicians and patients are likely to favour an oral treatment (i.e., sunitinib or pazopanib). Choosing between those two tyrosine kinase inhibitors may prove challenging. Two randomized trials have been conducted to facilitate treatment choices, COMPARZ, and PISCES. We discuss below the design of these trials, their results, their potential interpretation, and their clinical implications for selecting treatment. RECENT FINDINGS: Both trials were reported to meet the primary endpoint (i.e., noninferiority of pazopanib versus sunitinib) and patient's preference of pazopanib over sunitinib. However, several methodological aspects have raised doubts about the reliability of these conclusions. Pitfalls include the patients selected for the final analysis, discrepancies of results between the per protocol and intention-to-treat populations, the time points at which quality of life and disease were assessed. SUMMARY: A rigorous head-to-head comparison of pazopanib versus sunitinib is yet to be performed. Clinical considerations and physicans' experience, rather than the reported results of these trials, may continue to influence treatment choices.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/secundário , Indóis/uso terapêutico , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/patologia , Inibidores de Proteínas Quinases/uso terapêutico , Pirimidinas/uso terapêutico , Pirróis/uso terapêutico , Sulfonamidas/uso terapêutico , Antineoplásicos/efeitos adversos , Carcinoma de Células Renais/enzimologia , Carcinoma de Células Renais/mortalidade , Humanos , Indazóis , Indóis/efeitos adversos , Neoplasias Renais/enzimologia , Neoplasias Renais/mortalidade , Terapia de Alvo Molecular , Seleção de Pacientes , Inibidores de Proteínas Quinases/efeitos adversos , Pirimidinas/efeitos adversos , Pirróis/efeitos adversos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/efeitos adversos , Sunitinibe , Fatores de Tempo , Resultado do Tratamento
8.
Chin Clin Oncol ; 3(3): 40, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25841466

RESUMO

BACKGROUND: An independent data safety monitoring committee (IDMC) that is established to monitor the safety of participants in a clinical trial has, as its primary purpose, the protection of participants in the trial and the maintenance of the integrity of the trial. The IDMC should operate under a clear charter, with expectations understood by all its members. The investigators and sponsors should trust their IDMCs and give the IDMC the tools that it needs to operate effectively. The need to separate the investigators of randomized clinical trials from ongoing data has become widely appreciated. Especially when the study in question is a so-called 'phase III', or confirmatory, trial, knowledge of ongoing results can subtly or explicitly affect the care of participants in the trial, the methods of data collection, and the recruitment of new participants into the trial. These changes, if data-driven, can induce bias and therefore affect the scientific integrity of the trial. Failure to monitor the ongoing data, however, may put patients at undesirable risk, especially if emerging data indicate an unknown adverse consequence of therapy. The use of IDMCs has increased perhaps in response to the growing sophistication of the community of clinical trialists, the US Food and Drug Administration (FDA) draft guidance on data monitoring committees, the US National Institutes of Health (NIH)'s current rules for data monitoring plans, and the Data Monitoring Committees: Lessons, Ethics, Statistics Study Group from the UK National Health Service (DAMOCLES) recommendations. METHODS: This article summarizes and describes the design and operations of IDMCs in oncology. RESULTS: IDMCs in oncology share many similarities with IDMCs in other disease areas, but the particular nature of cancer patients affects the operation of these committees. COMMENTS: IDMC are important in oncology clinical trials because of the severity of illness and the often toxic effects of treatments.

11.
Pharm Stat ; 10(3): 213-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20568099

RESUMO

Evaluation (or assessment)-time bias can arise in oncology trials that study progression-free survival (PFS) when randomized groups have different patterns of timing of assessments. Modelling or computer simulation is sometimes used to explore the extent of such bias; valid results require building such simulations under realistic assumptions concerning the timing of assessments. This paper considers a trial that used a logrank test where computer simulations were based on unrealistic assumptions that severely overestimated the extent of potential bias. The paper shows that seemingly small differences in assumptions can lead to dramatic differences in the apparent operating characteristics of logrank tests.


Assuntos
Viés , Modelos Teóricos , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Antineoplásicos/uso terapêutico , Antineoplásicos Alquilantes/uso terapêutico , Simulação por Computador , Dacarbazina/uso terapêutico , Intervalo Livre de Doença , Humanos , Estimativa de Kaplan-Meier , Melanoma/tratamento farmacológico , Melanoma/epidemiologia , Avaliação de Processos e Resultados em Cuidados de Saúde , Reprodutibilidade dos Testes , Tionucleotídeos/uso terapêutico , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , United States Food and Drug Administration
12.
Ophthalmology ; 116(10 Suppl): S8-14, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19800537

RESUMO

In a clinical trial of age-related macular degeneration (AMD), the outcome measure chosen to assess the efficacy of treatment should reflect the purpose of the trial and the stage of development of the treatment. This article considers 3 classes of outcomes: continuous variables, such as mean change in best visual acuity; binary (2-category) variables, such as experiencing a 15-letter loss; or 3-category variables, such as experiencing either a 15-letter loss or 15-letter gain. Each type of outcome has advantages and disadvantages. Trials using outcomes based on means require much smaller sample sizes than trials based on 2- or 3-category variables, but means do not address the experience of individuals. Two- and 3-category variables show what happens to individuals, but they are subject to misclassification and are statistically inefficient. The authors recommend considering continuous measures for early stage trials and for trials studying various dose regimens when a treatment has been well characterized. However, 2- and 3-category outcomes are particularly useful in confirmatory phase 3 trials of a new therapy. A new graphical method is proposed to provide insight into the distribution of the time course of changes in acuity on an individual patient basis.


Assuntos
Degeneração Macular/terapia , Avaliação de Resultados em Cuidados de Saúde , Visão Ocular/fisiologia , Acuidade Visual/fisiologia , Inibidores da Angiogênese/uso terapêutico , Animais , Progressão da Doença , Seguimentos , Humanos , Degeneração Macular/fisiopatologia , Tamanho da Amostra , Fatores de Tempo , Resultado do Tratamento
13.
J Urol ; 181(4): 1642-57, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19249063

RESUMO

PURPOSE: To develop an evidence-based guideline on the use of 5-alpha-reductase inhibitors (5-ARIs) for prostate cancer chemoprevention. METHODS: The American Society of Clinical Oncology (ASCO) Health Services Committee (HSC), ASCO Cancer Prevention Committee, and the American Urological Association Practice Guidelines Committee jointly convened a Panel of experts, who used the results from a systematic review of the literature to develop evidence-based recommendations on the use of 5-ARIs for prostate cancer chemoprevention. RESULTS: The systematic review completed for this guideline identified 15 randomized clinical trials that met the inclusion criteria, nine of which reported prostate cancer period prevalence. CONCLUSION: Asymptomatic men with a prostate-specific antigen (PSA)

Assuntos
Colestenona 5 alfa-Redutase/antagonistas & inibidores , Neoplasias da Próstata/prevenção & controle , Quimioprevenção , Humanos , Masculino
14.
J Clin Oncol ; 27(9): 1502-16, 2009 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-19252137

RESUMO

PURPOSE To develop an evidence-based guideline on the use of 5-alpha-reductase inhibitors (5-ARIs) for prostate cancer chemoprevention. METHODS The American Society of Clinical Oncology (ASCO) Health Services Committee (HSC), ASCO Cancer Prevention Committee, and the American Urological Association Practice Guidelines Committee jointly convened a Panel of experts, who used the results from a systematic review of the literature to develop evidence-based recommendations on the use of 5-ARIs for prostate cancer chemoprevention. Results The systematic review completed for this guideline identified 15 randomized clinical trials that met the inclusion criteria, nine of which reported prostate cancer period prevalence. CONCLUSION Asymptomatic men with a prostate-specific antigen (PSA)

Assuntos
Inibidores de 5-alfa Redutase , Inibidores Enzimáticos/uso terapêutico , Neoplasias da Próstata/prevenção & controle , Humanos , Masculino , Neoplasias da Próstata/enzimologia
17.
Clin Trials ; 4(3): 218-34, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17715247

RESUMO

Data Safety Monitoring Committees (DSMB) for large, long-term randomized trials of agents in common use face challenging problems especially when the emerging data indicate unanticipated effects. The DSMB for the Women's Health Initiative Clinical Trials, on observing early indication of a surprising adverse cardiovascular effect of post-menopausal hormones, spent several years deliberating what recommendations it should make. This paper describes the dilemmas faced by the DSMB and the considerations it made over the course of its existence. The paper concludes with some recommendations for other DSMBs.


Assuntos
Comitês de Monitoramento de Dados de Ensaios Clínicos/organização & administração , Terapia de Reposição de Estrogênios , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Saúde da Mulher , Cálcio/uso terapêutico , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/prevenção & controle , Interpretação Estatística de Dados , Suplementos Nutricionais , Estrogênios/uso terapêutico , Feminino , Humanos , Congêneres da Progesterona/uso terapêutico , Projetos de Pesquisa , Medição de Risco , Vitamina D/uso terapêutico
18.
Circulation ; 114(10): 1028-35, 2006 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-16943394

RESUMO

BACKGROUND: Cyclooxygenase-2 (COX-2) inhibitors have been shown to reduce colorectal adenomas but have been associated with increased cardiovascular risk. METHODS AND RESULTS: The Adenoma Prevention With Celecoxib (APC) trial studied celecoxib 200 mg twice daily and 400 mg twice daily and the Prevention of Spontaneous Adenomatous Polyps (PreSAP) trial used 400 mg once daily totest the efficacy and safety of celecoxib against placebo in reducing colorectal adenoma recurrence after polypectomy. An independent safety committee for both studies adjudicated and categorized serious cardiovascular events and then combined individual patient data from these long-term trials to improve the estimate of the cardiovascular risk and blood pressure changes associated with celecoxib compared with placebo. For adjudicated cardiovascular events, 77% and 54% in APC and PreSAP, respectively, had 37 months of follow-up. For APC and PreSAP combined, 83 patients experienced cardiovascular death, nonfatal myocardial infarction, nonfatal stroke, or heart failure. The hazard ratio for this prespecified composite end point was 2.6 (95% confidence interval [CI], 1.1 to 6.1) in patients taking 200 mg twice daily, 3.4 (95% CI, 1.5 to 7.9) in patients taking 400 mg twice daily in APC, and 1.3 (95% CI, 0.6 to 2.6) in patients taking 400 mg once daily in PreSAP (P for heterogeneity = 0.13 comparing the combined doses in APC with the dose in PreSAP). The overall hazard ratio for this composite end point was 1.9 (95% CI, 1.1 to 3.1). Both dose groups in APC showed significant systolic blood pressure elevations at 1 and 3 years (200 mg twice daily: 1 year, 2.0 mm Hg; 3 years,2.6 mm Hg; 400 mg twice daily: 1 year, 2.9 mm Hg; 3 years, 5.2 mm Hg); however, the 400 mg once daily group inPreSAP did not (P0.0001 between studies). CONCLUSIONS: Celecoxib at 200 or 400 mg twice daily or 400 mg once daily showed a nearly 2-fold-increased cardiovascular risk. The trend for a dose-related increase in cardiovascular events and blood pressure raises the possibility that lower doses or other dose intervals may be associated with less cardiovascular risk.


Assuntos
Adenoma/prevenção & controle , Anti-Inflamatórios não Esteroides/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Neoplasias Colorretais/prevenção & controle , Pirazóis/uso terapêutico , Sulfonamidas/uso terapêutico , Adenoma/epidemiologia , Idoso , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/mortalidade , Fenômenos Fisiológicos Cardiovasculares , Celecoxib , Neoplasias Colorretais/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Medição de Risco , Segurança
19.
N Engl J Med ; 355(9): 873-84, 2006 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-16943400

RESUMO

BACKGROUND: Studies showing that drugs that inhibit cyclooxygenase-2 (COX-2) reduce the number of colorectal adenomas in animals and patients with familial adenomatous polyposis suggest that COX-2 inhibitors may also prevent sporadic colorectal neoplasia. METHODS: We randomly assigned patients who had adenomas removed before study entry to receive placebo (679 patients) or 200 mg (685 patients) or 400 mg (671 patients) of celecoxib twice daily. Randomization was stratified for the use of low-dose aspirin. Follow-up colonoscopies were performed at one and three years after randomization. The occurrence of newly detected colorectal adenomas was compared among the groups with the life-table extension of the Mantel-Haenszel test. RESULTS: Follow-up colonoscopies were completed at year 1 in 89.5 percent of randomized patients, and at year 3 in 75.7 percent. The estimated cumulative incidence of the detection of one or more adenomas by year 3 was 60.7 percent for patients receiving placebo, as compared with 43.2 percent for those receiving 200 mg of celecoxib twice a day (risk ratio, 0.67; 95 percent confidence interval, 0.59 to 0.77; P<0.001) and 37.5 percent for those receiving 400 mg of celecoxib twice a day (risk ratio, 0.55; 95 percent confidence interval, 0.48 to 0.64; P<0.001). Serious adverse events occurred in 18.8 percent of patients in the placebo group, as compared with 20.4 percent of those in the low-dose celecoxib group (risk ratio, 1.1; 95 percent confidence interval, 0.9 to 1.3; P=0.5) and 23.0 percent of those in the high-dose group (risk ratio, 1.2; 95 percent confidence interval, 1.0 to 1.5; P=0.06). As compared with placebo, celecoxib was associated with an increased risk of cardiovascular events (risk ratio for the low dose, 2.6; 95 percent confidence interval, 1.1 to 6.1; and risk ratio for the high dose, 3.4; 95 percent confidence interval, 1.5 to 7.9). CONCLUSIONS: These findings indicate that celecoxib is an effective agent for the prevention of colorectal adenomas but, because of potential cardiovascular events, cannot be routinely recommended for this indication. (ClinicalTrials.gov number, NCT00005094 [ClinicalTrials.gov].).


Assuntos
Adenoma/prevenção & controle , Neoplasias Colorretais/prevenção & controle , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Pirazóis/uso terapêutico , Sulfonamidas/uso terapêutico , Adenoma/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios não Esteroides/administração & dosagem , Aspirina/administração & dosagem , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/mortalidade , Celecoxib , Neoplasias Colorretais/tratamento farmacológico , Inibidores de Ciclo-Oxigenase 2/administração & dosagem , Inibidores de Ciclo-Oxigenase 2/efeitos adversos , Quimioterapia Combinada , Feminino , Gastroenteropatias/induzido quimicamente , Humanos , Nefropatias/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Pirazóis/administração & dosagem , Pirazóis/efeitos adversos , Prevenção Secundária , Sulfonamidas/administração & dosagem , Sulfonamidas/efeitos adversos
20.
N Engl J Med ; 355(9): 885-95, 2006 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-16943401

RESUMO

BACKGROUND: Overexpression of cyclooxygenase 2 (COX-2) has been associated with colorectal adenomatous polyps and cancer, prompting researchers to propose its inhibition as a chemopreventive intervention. METHODS: The Prevention of Colorectal Sporadic Adenomatous Polyps trial was a randomized, placebo-controlled, double-blind study of the COX-2 inhibitor celecoxib given daily in a single 400-mg dose. At 107 centers in 32 countries, we randomly assigned 1561 subjects who had had adenomas removed before enrollment to receive celecoxib (933 subjects) or placebo (628 subjects) daily, after stratification according to the use or nonuse of low-dose aspirin. The primary outcome was detection of adenomas at either year 1 or year 3 by colonoscopy and was compared among the groups with the use of the Mantel-Cox test. RESULTS: Colonoscopies were performed at year 1 on 88.7 percent of the subjects who had undergone randomization and at year 3 on 79.2 percent. Of the 557 subjects in the placebo group and the 840 subjects in the celecoxib group who were included in the efficacy analysis, 264 and 270, respectively, were found to have at least one adenoma at year 1, at year 3, or both. The cumulative rate of adenomas detected through year 3 was 33.6 percent in the celecoxib group and 49.3 percent in the placebo group (relative risk, 0.64; 95 percent confidence interval, 0.56 to 0.75; P<0.001). The cumulative rate of advanced adenomas detected through year 3 was 5.3 percent in the celecoxib group and 10.4 percent in the placebo group (relative risk, 0.49; 95 percent confidence interval, 0.33 to 0.73; P<0.001). Adjudicated serious cardiovascular events occurred in 2.5 percent of subjects in the celecoxib group and 1.9 percent of those in the placebo group (relative risk, 1.30; 95 percent confidence interval, 0.65 to 2.62). CONCLUSIONS: The use of 400 mg of celecoxib once daily significantly reduced the occurrence of colorectal adenomas within three years after polypectomy. (ClinicalTrials.gov number, NCT00141193 [ClinicalTrials.gov].).


Assuntos
Adenoma/prevenção & controle , Pólipos Adenomatosos/tratamento farmacológico , Neoplasias Colorretais/prevenção & controle , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Pirazóis/uso terapêutico , Sulfonamidas/uso terapêutico , Adenoma/tratamento farmacológico , Pólipos Adenomatosos/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios não Esteroides/administração & dosagem , Aspirina/administração & dosagem , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/mortalidade , Celecoxib , Neoplasias Colorretais/tratamento farmacológico , Inibidores de Ciclo-Oxigenase 2/administração & dosagem , Inibidores de Ciclo-Oxigenase 2/efeitos adversos , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Gastroenteropatias/induzido quimicamente , Humanos , Nefropatias/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Pirazóis/administração & dosagem , Pirazóis/efeitos adversos , Prevenção Secundária , Sulfonamidas/administração & dosagem , Sulfonamidas/efeitos adversos
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