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1.
Circ Cardiovasc Interv ; 17(5): e014054, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38696284

RESUMO

BACKGROUND: XC001 is a novel adenoviral-5 vector designed to express multiple isoforms of VEGF (vascular endothelial growth factor) and more safely and potently induce angiogenesis. The EXACT trial (Epicardial Delivery of XC001 Gene Therapy for Refractory Angina Coronary Treatment) assessed the safety and preliminary efficacy of XC001 in patients with no option refractory angina. METHODS: In this single-arm, multicenter, open-label trial, 32 patients with no option refractory angina received a single treatment of XC001 (1×1011 viral particles) via transepicardial delivery. RESULTS: There were no severe adverse events attributed to the study drug. Twenty expected severe adverse events in 13 patients were related to the surgical procedure. Total exercise duration increased from a mean±SD of 359.9±105.55 seconds at baseline to 448.2±168.45 (3 months), 449.2±175.9 (6 months), and 477.6±174.7 (12 months; +88.3 [95% CI, 37.1-139.5], +84.5 [95% CI, 34.1-134.9], and +115.5 [95% CI, 59.1-171.9]). Total myocardial perfusion deficit on positron emission tomography imaging decreased by 10.2% (95% CI, -3.1% to 23.5%), 14.3% (95% CI, 2.8%-25.7%), and 10.2% (95% CI, -0.8% to -21.2%). Angina frequency decreased from a mean±SD 12.2±12.5 episodes to 5.2±7.2 (3 months), 5.1±7.8 (6 months), and 2.7±4.8 (12 months), with an average decrease of 7.7 (95% CI, 4.1-11.3), 6.6 (95% CI, 3.5-9.7), and 8.8 (4.6-13.0) episodes at 3, 6, and 12 months. Angina class improved in 81% of participants at 6 months. CONCLUSIONS: XC001 administered via transepicardial delivery is safe and generally well tolerated. Exploratory improvements in total exercise duration, ischemic burden, and subjective measures support a biologic effect sustained to 12 months, warranting further investigation. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04125732.


Assuntos
Angina Pectoris , Terapia Genética , Vetores Genéticos , Neovascularização Fisiológica , Fator A de Crescimento do Endotélio Vascular , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Angina Pectoris/terapia , Angina Pectoris/fisiopatologia , Terapia Genética/efeitos adversos , Idoso , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/genética , Fatores de Tempo , Tolerância ao Exercício , Adenoviridae/genética , Recuperação de Função Fisiológica
2.
RMD Open ; 10(2)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609322

RESUMO

OBJECTIVES: Compare the risk of extended major adverse cardiovascular (CV) event (MACE) composite outcomes and component events in patients with rheumatoid arthritis (RA) treated with tofacitinib versus tumour necrosis factor inhibitors (TNFi) in Oral Rheumatoid Arthritis Trial (ORAL) Surveillance. METHODS: Patients with RA aged ≥50 years and with ≥1 additional CV risk factor received tofacitinib 5 mg or 10 mg two times per day or TNFi. MACE (non-fatal myocardial infarction (MI), non-fatal stroke or CV death (MACE-3)) was extended by sequential addition of CV events (hospitalisation for unstable angina (MACE-4), coronary revascularisation (MACE-5), transient ischaemic attack (MACE-6), peripheral vascular disease (MACE-7)), heart failure (HF) hospitalisation (MACE-8) and venous thromboembolism (VTE; (MACE-8 plus VTE)). HRs (tofacitinib vs TNFi) were evaluated for MACE and individual components. RESULTS: HRs for MACE-4 to MACE-8 with combined and individual tofacitinib doses versus TNFi were similar. Risk of MACE-8 plus VTE appeared similar with tofacitinib 5 mg two times per day versus TNFi (HR 1.12 (0.82 to 1.52)), but higher with tofacitinib 10 mg two times per day versus TNFi (HR 1.38 (1.02 to 1.85)). Risk of MI was higher with tofacitinib versus TNFi, but difference in risk of other individual CV events was not suggested. Across extended MACE definitions, risk appeared higher with tofacitinib versus TNFi in those with atherosclerotic CV disease or age ≥65 years. CONCLUSION: In ORAL Surveillance, risk of composite CV endpoints combining all ischaemic CV events and HF did not appear different with tofacitinib versus TNFi. The totality of CV risk was higher with tofacitinib 10 mg two times per day versus TNFi, driven by an increase in VTE. TRIAL REGISTRATION NUMBER: NCT02092467.


Assuntos
Artrite Reumatoide , Insuficiência Cardíaca , Infarto do Miocárdio , Pirimidinas , Tromboembolia Venosa , Humanos , Artrite Reumatoide/complicações , Artrite Reumatoide/tratamento farmacológico , Infarto do Miocárdio/epidemiologia , Infarto do Miocárdio/etiologia , Piperidinas/efeitos adversos , Inibidores do Fator de Necrose Tumoral
3.
Arthritis Rheumatol ; 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38481002

RESUMO

OBJECTIVE: The ORAL Surveillance trial found a dose-dependent increase in venous thromboembolism (VTE) and pulmonary embolism (PE) events with tofacitinib versus tumor necrosis factor inhibitors (TNFi). We aimed to assess VTE incidence over time and explore risk factors of VTE, including disease activity, in ORAL Surveillance. METHODS: Patients with rheumatoid arthritis (RA) aged 50 years or older with at least one additional cardiovascular risk factor received tofacitinib 5 or 10 mg twice daily (BID) or TNFi. Post hoc, cumulative probabilities and incidence rates (patients with first events/100 patient-years) by 6-month intervals were estimated for adjudicated VTE, deep vein thrombosis, and PE. Cox regression models identified risk factors. Clinical Disease Activity Index leading up to the event was explored in patients with VTE. RESULTS: Cumulative probabilities for VTE and PE were higher with tofacitinib 10 mg BID, but not 5 mg BID, versus TNFi. Incidence rates were consistent across 6-month intervals within treatments. Across treatments, risk factors for VTE included prior VTE, body mass index greater than or equal to 35 kg/m2, older age, and history of chronic lung disease. At the time of the event, most patients with VTE had active disease as defined by Clinical Disease Activity Index. CONCLUSION: Incidences of VTE and PE were higher with tofacitinib (10 > 5 mg BID) versus TNFi and were generally consistent over time. Across treatments, VTE risk factors were aligned with previous studies in the general RA population. These data highlight the importance of assessing VTE risk factors, including age, body mass index, and VTE history, when considering initiation of tofacitinib or TNFi in patients with active RA.

4.
Ann Rheum Dis ; 82(1): 119-129, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36137735

RESUMO

OBJECTIVES: Evaluate risk of major adverse cardiovascular events (MACE) with tofacitinib versus tumour necrosis factor inhibitors (TNFi) in patients with rheumatoid arthritis (RA) with or without a history of atherosclerotic cardiovascular disease (ASCVD) in ORAL Surveillance. METHODS: Patients with RA aged ≥50 years with ≥1 additional CV risk factor received tofacitinib 5 mg or 10 mg two times per day or TNFi. Hazard rations (HRs) were evaluated for the overall population and by history of ASCVD (exploratory analysis). RESULTS: Risk of MACE, myocardial infarction and sudden cardiac death were increased with tofacitinib versus TNFi in ORAL Surveillance. In patients with history of ASCVD (14.7%; 640/4362), MACE incidence was higher with tofacitinib 5 mg two times per day (8.3%; 17/204) and 10 mg two times per day (7.7%; 17/222) versus TNFi (4.2%; 9/214). HR (combined tofacitinib doses vs TNFi) was 1.98 (95% confidence interval (CI) 0.95 to 4.14; interaction p values: 0.196 (for HR)/0.059 (for incidence rate difference)). In patients without history of ASCVD, MACE HRs for tofacitinib 5 mg two times per day (2.4%; 30/1251) and 10 mg two times per day (2.8%; 34/1234) versus TNFi (2.3%; 28/1237) were, respectively, 1.03 (0.62 to 1.73) and 1.25 (0.76 to 2.07). CONCLUSIONS: This post hoc analysis observed higher MACE risk with tofacitinib versus TNFi in patients with RA and history of ASCVD. Among patients without history of ASCVD, all with prevalent CV risk factors, MACE risk did not appear different with tofacitinib 5 mg two times per day versus TNFi. Due to the exploratory nature of this analysis and low statistical power, we cannot exclude differential MACE risk for tofacitinib 5 mg two times per day versus TNFi among patients without history of ASCVD, but any absolute risk excess is likely low. TRIAL REGISTRATION NUMBER: NCT02092467.


Assuntos
Antirreumáticos , Artrite Reumatoide , Aterosclerose , Doenças Cardiovasculares , Humanos , Antirreumáticos/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Aterosclerose/epidemiologia , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/epidemiologia , Inibidores do Fator de Necrose Tumoral/efeitos adversos , Pessoa de Meia-Idade
5.
N Engl J Med ; 386(4): 316-326, 2022 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-35081280

RESUMO

BACKGROUND: Increases in lipid levels and cancers with tofacitinib prompted a trial of major adverse cardiovascular events (MACE) and cancers in patients with rheumatoid arthritis receiving tofacitinib as compared with a tumor necrosis factor (TNF) inhibitor. METHODS: We conducted a randomized, open-label, noninferiority, postauthorization, safety end-point trial involving patients with active rheumatoid arthritis despite methotrexate treatment who were 50 years of age or older and had at least one additional cardiovascular risk factor. Patients were randomly assigned in a 1:1:1 ratio to receive tofacitinib at a dose of 5 mg or 10 mg twice daily or a TNF inhibitor. The coprimary end points were adjudicated MACE and cancers, excluding nonmelanoma skin cancer. The noninferiority of tofacitinib would be shown if the upper boundary of the two-sided 95% confidence interval for the hazard ratio was less than 1.8 for the combined tofacitinib doses as compared with a TNF inhibitor. RESULTS: A total of 1455 patients received tofacitinib at a dose of 5 mg twice daily, 1456 received tofacitinib at a dose of 10 mg twice daily, and 1451 received a TNF inhibitor. During a median follow-up of 4.0 years, the incidences of MACE and cancer were higher with the combined tofacitinib doses (3.4% [98 patients] and 4.2% [122 patients], respectively) than with a TNF inhibitor (2.5% [37 patients] and 2.9% [42 patients]). The hazard ratios were 1.33 (95% confidence interval [CI], 0.91 to 1.94) for MACE and 1.48 (95% CI, 1.04 to 2.09) for cancers; the noninferiority of tofacitinib was not shown. The incidences of adjudicated opportunistic infections (including herpes zoster and tuberculosis), all herpes zoster (nonserious and serious), and adjudicated nonmelanoma skin cancer were higher with tofacitinib than with a TNF inhibitor. Efficacy was similar in all three groups, with improvements from month 2 that were sustained through trial completion. CONCLUSIONS: In this trial comparing the combined tofacitinib doses with a TNF inhibitor in a cardiovascular risk-enriched population, risks of MACE and cancers were higher with tofacitinib and did not meet noninferiority criteria. Several adverse events were more common with tofacitinib. (Funded by Pfizer; ORAL Surveillance ClinicalTrials.gov number, NCT02092467.).


Assuntos
Antirreumáticos/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Doenças Cardiovasculares/induzido quimicamente , Inibidores de Janus Quinases/efeitos adversos , Neoplasias/induzido quimicamente , Piperidinas/efeitos adversos , Pirimidinas/efeitos adversos , Idoso , Antirreumáticos/uso terapêutico , Doenças Cardiovasculares/epidemiologia , Feminino , Fatores de Risco de Doenças Cardíacas , Humanos , Incidência , Inibidores de Janus Quinases/administração & dosagem , Inibidores de Janus Quinases/uso terapêutico , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Piperidinas/administração & dosagem , Piperidinas/uso terapêutico , Pirimidinas/administração & dosagem , Pirimidinas/uso terapêutico
6.
JGH Open ; 5(7): 740-749, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34263067

RESUMO

BACKGROUND AND AIM: Liver histology changes are the current gold standard for evaluating non-alcoholic steatohepatitis (NASH), but are limited by their invasiveness and variability for sampling and interpretation. We evaluated noninvasive biomarkers as an indication of histologic changes in NASH. METHODS: Associations between 12-month biomarker and NASH Clinical Research Network histologic score changes in 339 patients with NASH in the EMMINENCE trial was examined with multivariable models and partial canonical correlation. A meta-analysis of 17 NASH trials including 3717 patients examined associations between these same changes and histologic response within treatment groups, and treatment effects on biomarkers and on liver histology. Biopsy measures assessed were changes in ballooning, steatosis, inflammation, and fibrosis, NASH improvement without worsening of fibrosis, and fibrosis improvement without worsening of NASH. All analytic methods suggest that a combination of aspartate aminotransferase (AST), cytokeratin-18 (CK-18 [M30 or M65]), and hemoglobin A1C (HbA1c) changes best predicts overall liver biopsy changes in response to interventions. RESULTS: The weighted average of standardized mean changes (0.403 × AST, 0.314 × CK-18, 0.283 × HbA1c) facilitated comparisons of within-group responses and treatment effects among studies included in the meta-analysis. This composite in EMMINENCE discriminated between patients with and without NASH resolution without worsening fibrosis with area under the receiver-operator characteristic curve of 0.7880, and for fibrosis improvement without NASH worsening of 0.7553. CONCLUSION: A composite score based on changes in AST, HbA1c, and CK-18 could serve as a surrogate for liver histologic improvement and an effective objective, noninvasive tool for comparative assessment of treatment effects of novel interventions.

7.
J Hepatol ; 73(6): 1322-1332, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32610115

RESUMO

BACKGROUND & AIMS: Liver biopsies are a critical component of pivotal studies in non-alcoholic steatohepatitis (NASH), constituting inclusion criteria, risk stratification factors and endpoints. We evaluated the reliability of NASH Clinical Research Network scoring of liver biopsies in a NASH clinical trial. METHODS: Digitized slides of 678 biopsies from 339 patients with paired biopsies randomized into the EMMINENCE study - examining a novel insulin sensitizer (MSDC-0602K) in NASH - were read independently by 3 hepatopathologists blinded to treatment code and scored using the NASH CRN histological scoring system. Various endpoints were computed from these scores. RESULTS: Inter-reader linearly weighted kappas were 0.609, 0.484, 0.328, and 0.517 for steatosis, fibrosis, lobular inflammation, and ballooning, respectively. Inter-reader unweighted kappas were 0.400 for the diagnosis of NASH, 0.396 for NASH resolution without worsening fibrosis, and 0.366 for fibrosis improvement without worsening NASH. In the current study, 46.3% of the patients included in the study based on 1 hepatopathologist's qualifying reading were deemed not to meet the study's histologic inclusion criteria by at least 1 of the 3 hepatopathologists. The MSDC-0602K treatment effect was lowest for those histologic features with lower inter-reader reliability. Simulations show that the lack of reliability of endpoints and inclusion criteria can drastically reduce study power - from >90% in a well-powered study to as low as 40%. CONCLUSIONS: The reliability of hepatopathologists' liver biopsy evaluation using currently accepted criteria is suboptimal. This lack of reliability may affect NASH pivotal studies by introducing patients who do not meet NASH study entry criteria, misclassifying fibrosis subgroups, and attenuating apparent treatment effects. LAY SUMMARY: Since liver biopsy analysis plays such an important role in clinical studies of non-alcoholic steatohepatitis, it is important to understand the reliability of hepato-pathologist readings. We examined both inter- and intra-reader variability in a large data set of paired liver biopsies from a clinical trial. We found very poor inter-reader and modest intra-reader variability. This result has important implications for entry criteria, fibrosis stratification, and the ability to measure a treatment effect in clinical trials.


Assuntos
Biópsia , Diabetes Mellitus Tipo 2 , Cirrose Hepática/patologia , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Acetofenonas/farmacologia , Biópsia/métodos , Biópsia/normas , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Progressão da Doença , Feminino , Humanos , Hipoglicemiantes/farmacologia , Resistência à Insulina , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/terapia , Prognóstico , Reprodutibilidade dos Testes , Projetos de Pesquisa , Medição de Risco/métodos , Tiazolidinedionas/farmacologia
8.
Diabetes Care ; 42(9): 1708-1715, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31331907

RESUMO

OBJECTIVE: The Follow-Up Study of patients previously enrolled in Exubera controlled clinical trials (FUSE) was designed to evaluate whether patients previously treated with Exubera (EXU; insulin human [rDNA origin], inhaled powder) in controlled clinical trials died because of incident primary lung cancer at a substantially higher rate than patients treated with a comparator. RESEARCH DESIGN AND METHODS: FUSE is a hybrid, randomized, controlled trial/cohort study including participants of 17 prior EXU clinical trials. Pooled patient data from these trials were used, and the subset of patients enrolled in the follow-up cohort study was followed prospectively for 2 years in order to evaluate the incidence of fatal and nonfatal primary lung cancers and all-cause mortality. RESULTS: There were 24,409 person-years (PY) of observation among 7,439 trial patients, with 4,017 PY (16.5%) from the period after the trials but before the prospective follow-up and 5,299 PY (21.7%) from the prospective follow-up. Just over half of the 2,631 patients (51.6%) in the prospective follow-up were randomized to EXU in the original trial. The incidence density ratio was 2.8 (95% CI 0.5, 28.5) for lung cancer-related mortality and 3.7 (95% CI 1.0, 20.7) for incident primary lung cancer. The hazard ratio for all-cause mortality was 0.81 (95% CI 0.60, 1.10). CONCLUSIONS: These data cannot exclude an increased risk of lung cancer-related mortality associated with EXU use. If real, the absolute increased risk of lung cancer-related mortality was small (0.48 cases per 1,000 PY). For all-cause mortality-the most reliably measured end point with the clearest interpretation-EXU users did not experience an excess all-cause death rate (relative or absolute) compared with users of other diabetes treatments over the study period.


Assuntos
Diabetes Mellitus/mortalidade , Hipoglicemiantes/efeitos adversos , Insulina Regular Humana/efeitos adversos , Insulina/efeitos adversos , Neoplasias Pulmonares/mortalidade , Administração por Inalação , Adulto , Estudos de Coortes , Diabetes Mellitus/tratamento farmacológico , Feminino , Seguimentos , Humanos , Incidência , Neoplasias Pulmonares/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto
9.
Stat Med ; 35(20): 3537-48, 2016 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-26999553

RESUMO

Propensity score (PS) methods have been used extensively to adjust for confounding factors in the statistical analysis of observational data in comparative effectiveness research. There are four major PS-based adjustment approaches: PS matching, PS stratification, covariate adjustment by PS, and PS-based inverse probability weighting. Though covariate adjustment by PS is one of the most frequently used PS-based methods in clinical research, the conventional variance estimation of the treatment effects estimate under covariate adjustment by PS is biased. As Stampf et al. have shown, this bias in variance estimation is likely to lead to invalid statistical inference and could result in erroneous public health conclusions (e.g., food and drug safety and adverse events surveillance). To address this issue, we propose a two-stage analytic procedure to develop a valid variance estimator for the covariate adjustment by PS analysis strategy. We also carry out a simple empirical bootstrap resampling scheme. Both proposed procedures are implemented in an R function for public use. Extensive simulation results demonstrate the bias in the conventional variance estimator and show that both proposed variance estimators offer valid estimates for the true variance, and they are robust to complex confounding structures. The proposed methods are illustrated for a post-surgery pain study. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Fatores de Confusão Epidemiológicos , Pontuação de Propensão , Viés , Humanos , Estudos Observacionais como Assunto
10.
J Med Chem ; 59(5): 2205-21, 2016 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-26881291

RESUMO

Anthracyclines are a class of antitumor compounds that are successful and widely used but suffer from cardiotoxicity and acquired tumor resistance. Formaldehyde interacts with anthracyclines to enhance antitumor efficacy, bypass resistance mechanisms, improve the therapeutic profile, and change the mechanism of action from a topoisomerase II poison to a DNA cross-linker. Contrary to current dogma, we show that both efficient DNA cross-linking and potent synergy in combination with formaldehyde correlate with the anthracycline's ability to form cyclic formaldehyde conjugates as oxazolidine moieties and that the cyclic conjugates are better cross-linking agents and cytotoxins than acyclic conjugates. We also provide evidence that suggests that the oxazolidine forms in situ, since cotreatment with doxorubicin and formaldehyde is highly cytotoxic to dox-resistant tumor cell lines, and that this benefit is absent in combinations of formaldehyde and epirubicin, which cannot form stable oxazolidines. These results have potential clinical implications in the active field of anthracycline prodrug design and development.


Assuntos
Antineoplásicos/farmacologia , Reagentes de Ligações Cruzadas/farmacologia , DNA de Neoplasias/química , Doxorrubicina/farmacologia , Formaldeído/farmacologia , Oxazóis/farmacologia , Pró-Fármacos/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Reagentes de Ligações Cruzadas/síntese química , Reagentes de Ligações Cruzadas/química , DNA de Neoplasias/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/análogos & derivados , Doxorrubicina/biossíntese , Doxorrubicina/química , Ensaios de Seleção de Medicamentos Antitumorais , Esterases/metabolismo , Formaldeído/química , Humanos , Fígado/enzimologia , Estrutura Molecular , Oxazóis/síntese química , Oxazóis/química , Pró-Fármacos/síntese química , Pró-Fármacos/química , Relação Estrutura-Atividade , Suínos , Células Tumorais Cultivadas
11.
Eur Respir J ; 46(1): 243-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25900377

RESUMO

The past decade has seen substantial progress in understanding the pathobiology, natural history, and clinical significance of idiopathic pulmonary fibrosis (IPF), culminating in the establishment of two effective medical therapies. Now seems an important time to reconsider the design and conduct of future IPF clinical trials. Building on lessons learned over the past decade, we use this perspective to lay out four key considerations for moving forward effectively and efficiently with the next generation of clinical trials in IPF. These are: development of a coordinated IPF clinical trials network; establishment of expectations for early phase proof of concept studies; adaptation of late-phase efficacy trial designs to the emergence of approved therapies, and; agreement on primary end-points for late phase clinical trials. Continued progress in the field of IPF will require creativity and collaboration on the part of all stakeholders. We believe that addressing these four considerations will encourage and enable investment in this new era of drug development in IPF, and will lead to more rapid development of effective therapies.


Assuntos
Ensaios Clínicos como Assunto , Fibrose Pulmonar Idiopática/terapia , Biomarcadores/sangue , Progressão da Doença , Humanos , Fibrose Pulmonar Idiopática/tratamento farmacológico , Pneumologia/tendências , Projetos de Pesquisa , Resultado do Tratamento
12.
J Biopharm Stat ; 25(6): 1161-78, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25331097

RESUMO

Substantial heterogeneity in treatment effects across subgroups can cause significant findings in the overall population to be driven predominantly by those of a certain subgroup, thus raising concern on whether the treatment should be prescribed for the least benefitted subgroup. Because of its low power, a nonsignificant interaction test can lead to incorrectly prescribing treatment for the overall population. This article investigates the power of the interaction test and its implications. Also, it investigates the probability of prescribing the treatment to a nonbenefitted subgroup on the basis of a nonsignificant interaction test and other recently proposed criteria.


Assuntos
Ensaios Clínicos como Assunto/estatística & dados numéricos , Algoritmos , Antibióticos Antineoplásicos/uso terapêutico , Antineoplásicos/uso terapêutico , Aspirina/uso terapêutico , Ensaios Clínicos Fase III como Assunto/estatística & dados numéricos , Clopidogrel , Doxorrubicina/uso terapêutico , Feminino , Humanos , Isquemia/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Reprodutibilidade dos Testes , Projetos de Pesquisa/estatística & dados numéricos , Tamanho da Amostra , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêutico , Topotecan/uso terapêutico
13.
J Med Chem ; 52(23): 7678-88, 2009 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-19634903

RESUMO

Doxazolidine (Doxaz) is a functionally distinct formaldehyde conjugate of doxorubicin (Dox) that induces cancer cell death in Dox-sensitive and resistant cells. Pentyl PABC-Doxaz (PPD) is a prodrug of Doxaz that is activated by carboxylesterase 2 (CES2), which is expressed by liver, non-small-cell lung, colon, pancreatic, renal, and thyroid cancer cells. Here, we demonstrate that in two murine models, PPD was effective at slowing tumor growth and demonstrated markedly reduced cardiotoxic and nephrotoxic effects, as well as better tolerance, relative to Dox. Hepatotoxicity, consistent with liver expression of the murine CES2 homologue, was induced by PPD. Unlike irinotecan, a clinical CES2-activated prodrug, PPD produced no visible gastrointestinal damage. Finally, we demonstrate that cellular response to PPD may be predicted with good accuracy using CES2 expression and Doxaz sensitivity, suggesting that these metrics may be useful as clinical biomarkers for sensitivity of a specific tumor to PPD treatment.


Assuntos
Carbamatos/metabolismo , Carbamatos/farmacologia , Carboxilesterase/metabolismo , Doxorrubicina/análogos & derivados , Oxazóis/metabolismo , Pró-Fármacos/metabolismo , Pró-Fármacos/farmacologia , Animais , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Western Blotting , Carbamatos/química , Carbamatos/toxicidade , Carboxilesterase/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/metabolismo , Doxorrubicina/farmacologia , Doxorrubicina/toxicidade , Avaliação Pré-Clínica de Medicamentos , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Miócitos Cardíacos/efeitos dos fármacos , Neoplasias/enzimologia , Neoplasias/patologia , Oxazóis/farmacologia , Pró-Fármacos/química , Pró-Fármacos/toxicidade , Ratos , Análise de Regressão
14.
J Periodontol ; 78(7 Suppl): 1400-6, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17610397

RESUMO

BACKGROUND: The goal of public health research often involves estimating clinical outcomes for a broad target population. The gold standard for the basis of such inference is a nationally representative survey that includes a clinical component. The cost of this gold standard can be prohibitive, and alternative approaches are needed. We propose a statistical methodology for projecting estimates from a clinical subsample to a larger survey population that has utility in periodontal research. METHODS: The statistical methodology consists of fitting prediction models to clinical outcome variables that are available only for a subset of the survey population. Variables measured on the larger survey population are included in the model as predictors. The resulting prediction equations are applied to the entire survey population to produce estimates of prevalence for the clinical outcomes of interest. Methods for computing variance estimates for the model-based predictions also are proposed. RESULTS: This projection methodology was developed originally for use with a nationally representative sample of the veteran population in the United States as part of the National Vietnam Veterans Readjustment Study. Details of the projection methodology and illustration of its use are provided. Issues associated with the application of this methodology to periodontal research are discussed. CONCLUSIONS: The proposed projection methodology supports valid inference about clinical outcomes to a broad population using data from a more narrowly defined clinical subsample. This approach is useful in addressing important public health questions until such time as a nationally representative clinical study can be undertaken.


Assuntos
Epidemiologia/estatística & dados numéricos , Modelos Estatísticos , Vigilância da População , Algoritmos , Distúrbios de Guerra/epidemiologia , Previsões , Humanos , Modelos Logísticos , Programas de Rastreamento/métodos , Doenças Periodontais/epidemiologia , Vigilância da População/métodos , Prevalência , Probabilidade , Saúde Pública , Autoavaliação (Psicologia) , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Estados Unidos/epidemiologia , Veteranos/estatística & dados numéricos
15.
Am J Epidemiol ; 163(9): 838-48, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16554352

RESUMO

This study investigated the relation between weekly levels of influenza activity and the risk of acute influenza-like illness episodes among 8,323 healthy pregnant and postpartum women enrolled in a Puget Sound region, Washington, health maintenance organization, Group Health Cooperative, between June 1991 and December 1997. The authors classified weeks between October and May for isolate activity level based on surveillance data for influenza, respiratory syncytial virus, parainfluenza, and adenovirus infection. Influenza-like illness episodes were identified from medical encounters assigned a diagnostic code consistent with a symptomatic influenza infection. The authors compared the occurrence of influenza-like illness episodes within each pregnancy stage for periods with varying levels of influenza isolate detection in the community. Repeated-measures logistic regression methods accounted for time-dependent factors. The adjusted strength of association between influenza exposure and influenza-like illness episodes increased as the pregnancy stage progressed (first trimester odds ratio = 1.12, 95% confidence interval: 0.79, 1.59; second trimester odds ratio = 1.30, 95% confidence interval: 0.97, 1.73; third trimester odds ratio = 1.84, 95% confidence interval: 1.31, 2.59; postpartum period odds ratio = 2.28, 95% confidence interval: 1.42, 3.68). Pregnancy stage modified the association between influenza activity and influenza-like illness episodes. Findings estimate that 20-43 pregnant/postpartum women would need to be vaccinated with an 80% effective vaccine to prevent one influenza-like illness episode.


Assuntos
Influenza Humana/epidemiologia , Período Pós-Parto , Complicações Infecciosas na Gravidez/epidemiologia , Doença Aguda , Feminino , Humanos , Incidência , Influenza Humana/prevenção & controle , Razão de Chances , Gravidez , Complicações Infecciosas na Gravidez/prevenção & controle , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Vacinação , Washington/epidemiologia
16.
Diabetes Care ; 28(1): 20-6, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15616228

RESUMO

OBJECTIVE: To assess the effects of antidiabetic drugs on the risk of heart failure in patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: We conducted a retrospective cohort study with a newly diagnosed diabetes cohort of 25,690 patients registered in the U.K. General Practice Research Database, 1988-1999. We categorized person-time drug exposures to monotherapies in insulin, sulfonylureas (SUs), metformins, and other oral hypoglycemic agents (i.e., acarbose, guar gum) and combination therapy including insulin, combination therapy without insulin, and triple combination therapy with or without insulin. A drug-free time interval served as a reference category. Cox interval-wise (piece-wise) regression analyses were used. The main outcome was incident heart failure. RESULTS: Among 43,390 drug exposure intervals for 25,690 patients who had a mean follow-up period of 2.5 years, 1,409 patients developed heart failure. Heart failure occurred most frequently in SU monotherapy exposure. After adjusting for duration of diabetes, the timing and order of treatments received, and known risk factors for heart failure, we found no differential effects among type-specific therapies. Patients with any drug use within the first year after diabetes diagnosis had a 4.75-fold higher risk (hazard ratio) for heart failure than those with drug-free status but had no increased risk during subsequent years. CONCLUSIONS: In conclusion, the use of any pharmacological therapy for type 2 diabetes appears to be associated with an increased risk of heart failure. This risk does not persist beyond the first year after diagnosis of diabetes and does not appear to differ among the types of drug therapy examined. This observation suggests that the severity of diabetes or the preclinical duration of diabetes and the need for drug therapy, and not the therapy itself, is an explanation for heart failure in patients with type 2 diabetes.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Insuficiência Cardíaca/epidemiologia , Hipoglicemiantes/efeitos adversos , Adulto , Idoso , Índice de Massa Corporal , Estudos de Coortes , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/epidemiologia , Medicina de Família e Comunidade , Feminino , Humanos , Insulina/efeitos adversos , Insulina/uso terapêutico , Masculino , Metformina/efeitos adversos , Metformina/uso terapêutico , Pessoa de Meia-Idade , Atenção Primária à Saúde , Estudos Retrospectivos , Fatores de Risco , Fumar , Reino Unido/epidemiologia
17.
J Biopharm Stat ; 14(2): 415-37, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15206537

RESUMO

Double-blind placebo-controlled clinical trials in metastatic bone disease considered counts of morbid events as the clinical outcome measure. These (recurrent) skeletal events were derived from a composite endpoint based on the necessity of medical interventions against bone pain or incident fractures. The trials were conducted for regulatory approval of therapy with bisphosphonates and were intended to demonstrate that an active treatment reduces the occurrence of skeletal events. The advanced morbidity of the patients led to a substantial amount of premature discontinuations, because of early death or because of progression of the basic disease. In some trials the discontinuations were unbalanced between treatment arms, where there were more dropouts under placebo. These effects contribute to a high portion of patients with no morbidity events. This background presents difficulties for the task of defining statistics that validly quantify skeletal morbidity in these trials while keeping the necessary simplicity so as to be accepted by health authorities and a clinical audience. Guided by this regulatory context, this paper compares the performance of five (simple) approaches to quantifying skeletal morbidity. Key criteria are bias and validity under different dropout scenarios, as well as the capability to demonstrate treatment effects. Based on theoretical considerations, two simulation studies, and real data results, a morbidity measure in the form of a smoothed rate was favored: this is a rate estimate in the individual patient of the form (y + c)(T + d)(-1), where y is the count of events, T is the patient's observation time, and c, d are constants to be appropriately chosen. This morbidity measure performed well in the simulation studies and showed a wanted insensitivity to dropout patterns. It outperforms the simple rate y/T due to the high portion of patients without events. Rates of this type were used before in the quantal bioassay and have a strong relationship to Bayesian approaches. Hence, these measures represent a good approach to handle the inherent difficulties of morbid event data in severely diseased patient populations, still offering sufficient simplicity.


Assuntos
Neoplasias Ósseas/epidemiologia , Neoplasias Ósseas/secundário , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Humanos , Recidiva
18.
Stat Med ; 23(7): 1075-93, 2004 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-15057879

RESUMO

This paper addresses the problem of combining information from independent clinical trials which compare survival distributions of two treatment groups. Current meta-analytic methods which take censoring into account are often not feasible for meta-analyses which synthesize summarized results in published (or unpublished) references, as these methods require information usually not reported. The paper presents methodology which uses the log(-log) survival function difference, (i.e. log(-logS2(t))-log(-logS1(t)), as the contrast index to represent the multiplicative treatment effect on survival in independent trials. This article shows by the second mean value theorem for integrals that this contrast index, denoted as theta, is interpretable as a weighted average on a natural logarithmic scale of hazard ratios within the interval [0,t] in a trial. When the within-trial proportional hazards assumption is true, theta is the logarithm of the proportionality constant for the common hazard ratio for the interval considered within the trial. In this situation, an important advantage of using theta as a contrast index in the proposed methodology is that the estimation of theta is not affected by length of follow-up time. Other commonly used indices such as the odds ratio, risk ratio and risk differences do not have this invariance property under the proportional hazard model, since their estimation may be affected by length of follow-up time as a technical artefact. Thus, the proposed methodology obviates problems which often occur in survival meta-analysis because trials do not report survival at the same length of follow-up time. Even when the within-trial proportional hazards assumption is not realistic, the proposed methodology has the capability of testing a global null hypothesis of no multiplicative treatment effect on the survival distributions of two groups for all studies. A discussion of weighting schemes for meta-analysis is provided, in particular, a weighting scheme based on effective sample sizes is suggested for the meta-analysis of time-to-event data which involves censoring. A medical example illustrating the methodology is given. A simulation investigation suggested that the methodology performs well in the presence of moderate censoring.


Assuntos
Ensaios Clínicos como Assunto/métodos , Metanálise como Assunto , Análise de Sobrevida , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Resultado do Tratamento
19.
Ann Surg Oncol ; 9(9): 847-54, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12417505

RESUMO

BACKGROUND: Recent publications suggest an inverse relationship between mortality rates in the Whipple procedure for periampullary cancer and hospital volume/teaching status. METHODS: The Nationwide Inpatient Sample database from 1988 to 1995, containing 24926 patients undergoing pancreatectomy for periampullary cancer, was used. RESULTS: The mean number of procedures per hospital per year was 1.5, and the overall mortality was 14%. The volume of procedures per year increased from the rural to the urban nonteaching hospitals to the urban teaching hospitals (.6, 1.1, and 2.7, respectively), with a steady decrease in mortality among the three hospital types (18%, 15%, and 11%). A multiple logistic regression model with mortality odds ratios (ORs) showed that male sex (OR, 1.3), increasing age (OR, 1.6 to 6.7 in decades from 50 to > or=80 vs. <50 years), emergency admission (OR, 1.5), and hospital volume (less than one vs. one or more cases per year; OR, 1.5) were significantly predictive for increased in-hospital mortality. CONCLUSIONS: In-hospital mortality in the low-volume hospital setting is prohibitive, and review of each institution's mortality rates must occur before these procedures are performed in those institutions. In addition, patients over the age of 60 years, male patients, and those with an urgent admission are at a significant risk of in-hospital death, and consideration should be given toward transfer to an experienced institution.


Assuntos
Pancreaticoduodenectomia/mortalidade , Fatores Etários , Idoso , Competência Clínica , Feminino , Mortalidade Hospitalar , Hospitais/estatística & dados numéricos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Pancreaticoduodenectomia/estatística & dados numéricos , Medição de Risco , Estados Unidos/epidemiologia
20.
Prev Sci ; 3(1): 35-42, 2002 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12002557

RESUMO

Reducing the prevalence of adolescent cigarette smoking and alcohol drinking are public health goals of the United States. Although families have strong influence on their children, few randomized studies have examined whether family-directed programs influence those behaviors in general universal populations. This paper reports findings from an evaluation of a family program that features the mailing of four booklets to adult family members with follow-up telephone calls by health educators. A national sample of adolescent-parent pairs and a randomized experimental design were used to evaluate the program. Baseline users and nonusers of those substances were considered simultaneously in analyses so that program influences on smoking and drinking prevalence could be examined. The findings suggest that the program significantly reduced the prevalence of smoking cigarettes and drinking alcohol among adolescents. These findings are discussed in the context of earlier reports of research on the family program and implications for public health.


Assuntos
Consumo de Bebidas Alcoólicas/prevenção & controle , Relações Profissional-Família , Avaliação de Programas e Projetos de Saúde , Prevenção do Hábito de Fumar , Adolescente , Consumo de Bebidas Alcoólicas/epidemiologia , Feminino , Seguimentos , Humanos , Masculino , Prevalência , Fumar/epidemiologia
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