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1.
Nat Methods ; 20(7): 1058-1069, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37248388

RESUMO

Highly multiplexed imaging holds enormous promise for understanding how spatial context shapes the activity of the genome and its products at multiple length scales. Here, we introduce a deep learning framework called CAMPA (Conditional Autoencoder for Multiplexed Pixel Analysis), which uses a conditional variational autoencoder to learn representations of molecular pixel profiles that are consistent across heterogeneous cell populations and experimental perturbations. Clustering these pixel-level representations identifies consistent subcellular landmarks, which can be quantitatively compared in terms of their size, shape, molecular composition and relative spatial organization. Using high-resolution multiplexed immunofluorescence, this reveals how subcellular organization changes upon perturbation of RNA synthesis, RNA processing or cell size, and uncovers links between the molecular composition of membraneless organelles and cell-to-cell variability in bulk RNA synthesis rates. By capturing interpretable cellular phenotypes, we anticipate that CAMPA will greatly accelerate the systematic mapping of multiscale atlases of biological organization to identify the rules by which context shapes physiology and disease.


Assuntos
RNA , Análise por Conglomerados
2.
Genes Dev ; 31(21): 2115-2120, 2017 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-29212661

RESUMO

Epigenetic maintenance of gene repression is essential for development. Polycomb complexes are central to this memory, but many aspects of the underlying mechanism remain unclear. LIKE HETEROCHROMATIN PROTEIN 1 (LHP1) binds Polycomb-deposited H3K27me3 and is required for repression of many Polycomb target genes in Arabidopsis Here we show that LHP1 binds RNA in vitro through the intrinsically disordered hinge region. By independently perturbing the RNA-binding hinge region and H3K27me3 (trimethylation of histone H3 at Lys27) recognition, we found that both facilitate LHP1 localization and H3K27me3 maintenance. Disruption of the RNA-binding hinge region also prevented formation of subnuclear foci, structures potentially important for epigenetic repression.


Assuntos
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Proteínas Cromossômicas não Histona/metabolismo , Repressão Epigenética/genética , Proteínas Cromossômicas não Histona/genética , Regulação da Expressão Gênica de Plantas/genética , Histonas/metabolismo , Mutação/genética , Proteínas do Grupo Polycomb/genética , Proteínas do Grupo Polycomb/metabolismo , Motivos de Ligação ao RNA/genética
3.
Emerg Infect Dis ; 30(3): 530-538, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38407144

RESUMO

Persons living in long-term care facilities (LTCFs) were disproportionately affected by COVID-19. We used wastewater surveillance to detect SARS-CoV-2 infection in this setting by collecting and testing 24-hour composite wastewater samples 2-4 times weekly at 6 LTCFs in Kentucky, USA, during March 2021-February 2022. The LTCFs routinely tested staff and symptomatic and exposed residents for SARS-CoV-2 using rapid antigen tests. Of 780 wastewater samples analyzed, 22% (n = 173) had detectable SARS-CoV-2 RNA. The LTCFs reported 161 positive (of 16,905) SARS-CoV-2 clinical tests. The wastewater SARS-CoV-2 signal showed variable correlation with clinical test data; we observed the strongest correlations in the LTCFs with the most positive clinical tests (n = 45 and n = 58). Wastewater surveillance was 48% sensitive and 80% specific in identifying SARS-CoV-2 infections found on clinical testing, which was limited by frequency, coverage, and rapid antigen test performance.


Assuntos
COVID-19 , Águas Residuárias , Humanos , Kentucky/epidemiologia , Vigilância Epidemiológica Baseada em Águas Residuárias , Assistência de Longa Duração , RNA Viral , COVID-19/diagnóstico , COVID-19/epidemiologia , SARS-CoV-2
4.
Oncologist ; 29(2): e259-e265, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-37740501

RESUMO

Financial toxicity (FT) describes either objective or perceived excess financial strain due to a cancer diagnosis on the well-being of patients, families, and society. The consequences of FT have been shown to span countries of varied economic tiers and diverse healthcare models. This study attempts to describe FT and its effects in a lower- to middle-income country delivering predominantly public nonfee-levying healthcare. This was a cross-sectional study involving 210 patients with breast cancer of any stage (I to IV), interviewed between 6 and 18 months from the date of diagnosis. Financial toxicity was highly prevalent with 81% reporting 3 or more on a scale of 1 to 5. Costs incurred for travelling (94%), out-of-hospital investigations (87%), and consultation fees outside the public system (81%) were the most common contributors to FT. Daily compromises for food and education were made by 30% and 20%, respectively, with loss of work seen in over one-third. Greater FT was seen with advanced cancer stage and increasing distance to the nearest radiotherapy unit (P = .008 and .01, respectively). Family and relatives were the most common form of financial support (77.6%). In conclusion, FT is substantial in our group, with many having to make daily compromises for basic needs. Many opt to visit the fee-levying private sector for at least some part of their care, despite the availability of an established public nonfee-levying healthcare.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/epidemiologia , Estresse Financeiro , Sri Lanka/epidemiologia , Estudos Transversais , Atenção à Saúde
5.
N Engl J Med ; 385(9): 790-802, 2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34351721

RESUMO

BACKGROUND: Thrombosis and inflammation may contribute to the risk of death and complications among patients with coronavirus disease 2019 (Covid-19). We hypothesized that therapeutic-dose anticoagulation may improve outcomes in noncritically ill patients who are hospitalized with Covid-19. METHODS: In this open-label, adaptive, multiplatform, controlled trial, we randomly assigned patients who were hospitalized with Covid-19 and who were not critically ill (which was defined as an absence of critical care-level organ support at enrollment) to receive pragmatically defined regimens of either therapeutic-dose anticoagulation with heparin or usual-care pharmacologic thromboprophylaxis. The primary outcome was organ support-free days, evaluated on an ordinal scale that combined in-hospital death (assigned a value of -1) and the number of days free of cardiovascular or respiratory organ support up to day 21 among patients who survived to hospital discharge. This outcome was evaluated with the use of a Bayesian statistical model for all patients and according to the baseline d-dimer level. RESULTS: The trial was stopped when prespecified criteria for the superiority of therapeutic-dose anticoagulation were met. Among 2219 patients in the final analysis, the probability that therapeutic-dose anticoagulation increased organ support-free days as compared with usual-care thromboprophylaxis was 98.6% (adjusted odds ratio, 1.27; 95% credible interval, 1.03 to 1.58). The adjusted absolute between-group difference in survival until hospital discharge without organ support favoring therapeutic-dose anticoagulation was 4.0 percentage points (95% credible interval, 0.5 to 7.2). The final probability of the superiority of therapeutic-dose anticoagulation over usual-care thromboprophylaxis was 97.3% in the high d-dimer cohort, 92.9% in the low d-dimer cohort, and 97.3% in the unknown d-dimer cohort. Major bleeding occurred in 1.9% of the patients receiving therapeutic-dose anticoagulation and in 0.9% of those receiving thromboprophylaxis. CONCLUSIONS: In noncritically ill patients with Covid-19, an initial strategy of therapeutic-dose anticoagulation with heparin increased the probability of survival to hospital discharge with reduced use of cardiovascular or respiratory organ support as compared with usual-care thromboprophylaxis. (ATTACC, ACTIV-4a, and REMAP-CAP ClinicalTrials.gov numbers, NCT04372589, NCT04505774, NCT04359277, and NCT02735707.).


Assuntos
Anticoagulantes/administração & dosagem , Tratamento Farmacológico da COVID-19 , Heparina/administração & dosagem , Trombose/prevenção & controle , Adulto , Idoso , Anticoagulantes/efeitos adversos , Anticoagulantes/uso terapêutico , COVID-19/mortalidade , Feminino , Hemorragia/induzido quimicamente , Heparina/efeitos adversos , Heparina/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sobrevida
6.
Pharm Stat ; 2024 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-38676420

RESUMO

Inferentially seamless 2/3 designs are increasingly popular in clinical trials. It is important to understand their relative advantages compared with separate phase 2 and phase 3 trials, and to understand the consequences of design choices such as the proportion of patients included in the phase 2 portion of the design. Extending previous work in this area, we perform a simulation study across multiple numbers of arms and efficacy response curves. We consider a design space crossing the choice of a separate versus seamless design with the choice of allocating 0%-100% of available patients in phase 2, with the remainder in phase 3. The seamless designs achieve greater power than their separate trial counterparts. Importantly, the optimal seamless design is more robust than the optimal separate program, meaning that one range of values for the proportion of patients used in phase 2 (30%-50% of the total phase 2/3 sample size) is nearly optimal for a wide range of response scenarios. In contrast, a percentage of patients used in phase 2 for separate trials may be optimal for some alternative scenarios but decidedly inferior for other alternative scenarios. When operationally and scientifically viable, seamless trials provide superior performance compared with separate phase 2 and phase 3 trials. The results also provide guidance for the implementation of these trials in practice.

7.
Lancet Oncol ; 24(6): 624-635, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37269843

RESUMO

BACKGROUND: Criticisms have emerged that cancer medicines offer modest benefits at increasingly high prices. Reimbursement decisions made by health technology assessment (HTA) agencies have become a complex endeavour for cancer medicines. Most high-income countries (HICs) use HTA criteria to identify high-value medicines for reimbursement under public drug coverage plans. We compared HTA criteria specific for cancer medicines in economically similar HICs, to understand how these criteria contribute to reimbursement decisions. METHODS: We did an international, cross-sectional analysis in collaboration with author investigators across eight HICs, from the Group of Seven (known as G7; Canada, England, France, Germany, Italy, and Japan) and Oceania (Australia and New Zealand). Publicly available data from HTA agency reports and official documentation were extracted and analysed between Aug 15, 2021, and July 31, 2022. We collected data pertaining to the decision-making criteria used by the national HTA agency; HTA reimbursement status for 34 medicine-indication pairs corresponding to 15 unique US top-selling cancer medicines; and HTA reimbursement status for 18 cancer medicine-indication pairs (13 unique medicines) with minimal clinical benefit (score of 1 on the European Society of Medical Oncology Magnitude of Clinical Benefit Scale). Descriptive statistics were used to compare HTA decision criteria and drug reimbursement recommendations (or for Germany and Japan, final reimbursement status) across the eight countries. FINDINGS: Therapeutic impact related to clinical outcomes of the new medicine was a uniform criterion across the eight countries, whereas quality of evidence (under the remit of therapeutic impact assessment) and equity were infrequently cited criteria. Only the German HTA agency mandated that surrogate endpoints be validated in therapeutic impact assessment. All countries except Germany included formal cost-effectiveness analyses within HTA reports. England and Japan were the only countries that specified a cost-effectiveness threshold. Of the 34 medicine-indication pairs corresponding to US top-selling cancer medicines, Germany reimbursed the maximum (34 [100%]), followed by Italy (32 [94%] recommended for reimbursement), Japan (28 [82%] reimbursed), Australia, Canada, England, and France (27 [79%] recommended for reimbursement), and New Zealand (12 [35%] recommended for reimbursement). Of the 18 cancer medicine-indication pairs with marginal clinical benefit, Germany reimbursed 15 (83%) and Japan reimbursed 12 (67%). France recommended nine (50%) for reimbursement, followed by Italy (seven [39%]), Canada (five [28%]), and Australia and England (three [17%] each). New Zealand did not recommend any medicine-indications with marginal clinical benefit for reimbursement. Considering the overall cumulative proportion across the eight countries, 58 (21%) of 272 indications for the US top-selling medicines and 90 (63%) of 144 marginally beneficial medicine-indications were not recommended for reimbursement or reimbursed. INTERPRETATION: Our findings indicate discordance in public reimbursement decisions across economically similar countries, despite overlapping HTA decision criteria. This suggests a need for improved transparency around the nuances of the criteria to ensure improved access to high-value cancer medicines, and deprioritisation of low-value cancer medicines. Health systems have opportunities to improve their HTA decision-making processes by learning from the systems in other countries. FUNDING: None.


Assuntos
Neoplasias , Avaliação da Tecnologia Biomédica , Humanos , Estudos Transversais , França , Neoplasias/tratamento farmacológico , Oceania
8.
J Biol Chem ; 298(3): 101649, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35104504

RESUMO

RNA-binding proteins (RBPs) regulate the expression of large cohorts of RNA species to produce programmatic changes in cellular phenotypes. To describe the function of RBPs within a cell, it is key to identify their mRNA-binding partners. This is often done by crosslinking nucleic acids to RBPs, followed by chemical release of the nucleic acid fragments for analysis. However, this methodology is lengthy, which involves complex processing with attendant sample losses, thus large amounts of starting materials and prone to artifacts. To evaluate potential alternative technologies, we tested "exclusion-based" purification of immunoprecipitates (IFAST or SLIDE) and report here that these methods can efficiently, rapidly, and specifically isolate RBP-RNA complexes. The analysis requires less than 1% of the starting material required for techniques that include crosslinking. Depending on the antibody used, 50% to 100% starting protein can be retrieved, facilitating the assay of endogenous levels of RBPs; the isolated ribonucleoproteins are subsequently analyzed using standard techniques, to provide a comprehensive portrait of RBP complexes. Using exclusion-based techniques, we show that the mRNA-binding partners for RBP IGF2BP1 in cultured mammary epithelial cells are enriched in mRNAs important for detoxifying superoxides (specifically glutathione peroxidase [GPX]-1 and GPX-2) and mRNAs encoding mitochondrial proteins. We show that these interactions are functionally significant, as loss of function of IGF2BP1 leads to destabilization of GPX mRNAs and reduces mitochondrial membrane potential and oxygen consumption. We speculate that this underlies a consistent requirement for IGF2BP1 for the expression of clonogenic activity in vitro.


Assuntos
Glândulas Mamárias Animais , Glândulas Mamárias Humanas , Proteínas de Ligação a RNA , Animais , Células Epiteliais/metabolismo , Feminino , Humanos , Imunoprecipitação , Glândulas Mamárias Animais/citologia , Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Humanas/citologia , Glândulas Mamárias Humanas/metabolismo , RNA/metabolismo , RNA Mensageiro , Proteínas de Ligação a RNA/metabolismo
9.
JAMA ; 329(13): 1066-1077, 2023 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-36942550

RESUMO

Importance: Randomized clinical trials (RCTs) of therapeutic-dose heparin in patients hospitalized with COVID-19 produced conflicting results, possibly due to heterogeneity of treatment effect (HTE) across individuals. Better understanding of HTE could facilitate individualized clinical decision-making. Objective: To evaluate HTE of therapeutic-dose heparin for patients hospitalized for COVID-19 and to compare approaches to assessing HTE. Design, Setting, and Participants: Exploratory analysis of a multiplatform adaptive RCT of therapeutic-dose heparin vs usual care pharmacologic thromboprophylaxis in 3320 patients hospitalized for COVID-19 enrolled in North America, South America, Europe, Asia, and Australia between April 2020 and January 2021. Heterogeneity of treatment effect was assessed 3 ways: using (1) conventional subgroup analyses of baseline characteristics, (2) a multivariable outcome prediction model (risk-based approach), and (3) a multivariable causal forest model (effect-based approach). Analyses primarily used bayesian statistics, consistent with the original trial. Exposures: Participants were randomized to therapeutic-dose heparin or usual care pharmacologic thromboprophylaxis. Main Outcomes and Measures: Organ support-free days, assigning a value of -1 to those who died in the hospital and the number of days free of cardiovascular or respiratory organ support up to day 21 for those who survived to hospital discharge; and hospital survival. Results: Baseline demographic characteristics were similar between patients randomized to therapeutic-dose heparin or usual care (median age, 60 years; 38% female; 32% known non-White race; 45% Hispanic). In the overall multiplatform RCT population, therapeutic-dose heparin was not associated with an increase in organ support-free days (median value for the posterior distribution of the OR, 1.05; 95% credible interval, 0.91-1.22). In conventional subgroup analyses, the effect of therapeutic-dose heparin on organ support-free days differed between patients requiring organ support at baseline or not (median OR, 0.85 vs 1.30; posterior probability of difference in OR, 99.8%), between females and males (median OR, 0.87 vs 1.16; posterior probability of difference in OR, 96.4%), and between patients with lower body mass index (BMI <30) vs higher BMI groups (BMI ≥30; posterior probability of difference in ORs >90% for all comparisons). In risk-based analysis, patients at lowest risk of poor outcome had the highest propensity for benefit from heparin (lowest risk decile: posterior probability of OR >1, 92%) while those at highest risk were most likely to be harmed (highest risk decile: posterior probability of OR <1, 87%). In effect-based analysis, a subset of patients identified at high risk of harm (P = .05 for difference in treatment effect) tended to have high BMI and were more likely to require organ support at baseline. Conclusions and Relevance: Among patients hospitalized for COVID-19, the effect of therapeutic-dose heparin was heterogeneous. In all 3 approaches to assessing HTE, heparin was more likely to be beneficial in those who were less severely ill at presentation or had lower BMI and more likely to be harmful in sicker patients and those with higher BMI. The findings illustrate the importance of considering HTE in the design and analysis of RCTs. Trial Registration: ClinicalTrials.gov Identifiers: NCT02735707, NCT04505774, NCT04359277, NCT04372589.


Assuntos
COVID-19 , Tromboembolia Venosa , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Heparina/efeitos adversos , Anticoagulantes/efeitos adversos , Teorema de Bayes , Tromboembolia Venosa/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto
10.
JAMA ; 330(18): 1745-1759, 2023 11 14.
Artigo em Inglês | MEDLINE | ID: mdl-37877585

RESUMO

Importance: The efficacy of vitamin C for hospitalized patients with COVID-19 is uncertain. Objective: To determine whether vitamin C improves outcomes for patients with COVID-19. Design, Setting, and Participants: Two prospectively harmonized randomized clinical trials enrolled critically ill patients receiving organ support in intensive care units (90 sites) and patients who were not critically ill (40 sites) between July 23, 2020, and July 15, 2022, on 4 continents. Interventions: Patients were randomized to receive vitamin C administered intravenously or control (placebo or no vitamin C) every 6 hours for 96 hours (maximum of 16 doses). Main Outcomes and Measures: The primary outcome was a composite of organ support-free days defined as days alive and free of respiratory and cardiovascular organ support in the intensive care unit up to day 21 and survival to hospital discharge. Values ranged from -1 organ support-free days for patients experiencing in-hospital death to 22 organ support-free days for those who survived without needing organ support. The primary analysis used a bayesian cumulative logistic model. An odds ratio (OR) greater than 1 represented efficacy (improved survival, more organ support-free days, or both), an OR less than 1 represented harm, and an OR less than 1.2 represented futility. Results: Enrollment was terminated after statistical triggers for harm and futility were met. The trials had primary outcome data for 1568 critically ill patients (1037 in the vitamin C group and 531 in the control group; median age, 60 years [IQR, 50-70 years]; 35.9% were female) and 1022 patients who were not critically ill (456 in the vitamin C group and 566 in the control group; median age, 62 years [IQR, 51-72 years]; 39.6% were female). Among critically ill patients, the median number of organ support-free days was 7 (IQR, -1 to 17 days) for the vitamin C group vs 10 (IQR, -1 to 17 days) for the control group (adjusted proportional OR, 0.88 [95% credible interval {CrI}, 0.73 to 1.06]) and the posterior probabilities were 8.6% (efficacy), 91.4% (harm), and 99.9% (futility). Among patients who were not critically ill, the median number of organ support-free days was 22 (IQR, 18 to 22 days) for the vitamin C group vs 22 (IQR, 21 to 22 days) for the control group (adjusted proportional OR, 0.80 [95% CrI, 0.60 to 1.01]) and the posterior probabilities were 2.9% (efficacy), 97.1% (harm), and greater than 99.9% (futility). Among critically ill patients, survival to hospital discharge was 61.9% (642/1037) for the vitamin C group vs 64.6% (343/531) for the control group (adjusted OR, 0.92 [95% CrI, 0.73 to 1.17]) and the posterior probability was 24.0% for efficacy. Among patients who were not critically ill, survival to hospital discharge was 85.1% (388/456) for the vitamin C group vs 86.6% (490/566) for the control group (adjusted OR, 0.86 [95% CrI, 0.61 to 1.17]) and the posterior probability was 17.8% for efficacy. Conclusions and Relevance: In hospitalized patients with COVID-19, vitamin C had low probability of improving the primary composite outcome of organ support-free days and hospital survival. Trial Registration: ClinicalTrials.gov Identifiers: NCT04401150 (LOVIT-COVID) and NCT02735707 (REMAP-CAP).


Assuntos
COVID-19 , Sepse , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Ácido Ascórbico/uso terapêutico , Estado Terminal/terapia , Estado Terminal/mortalidade , Mortalidade Hospitalar , Teorema de Bayes , Ensaios Clínicos Controlados Aleatórios como Assunto , Vitaminas/uso terapêutico , Sepse/tratamento farmacológico
11.
Clin Trials ; 19(5): 490-501, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35993547

RESUMO

BACKGROUND: Multi-arm platform trials investigate multiple agents simultaneously, typically with staggered entry and exit of experimental treatment arms versus a shared control arm. In such settings, there is considerable debate whether to limit analyses for a treatment arm to concurrent randomized control subjects or to allow comparisons to both concurrent and non-concurrent (pooled) control subjects. The potential bias from temporal drift over time is at the core of this debate. METHODS: We propose time-adjusted analyses, including a "Bayesian Time Machine," to model potential temporal drift in the entire study population, such that primary analyses can incorporate all randomized control subjects from the platform trial. We conduct a simulation study to assess performance relative to utilizing concurrent or pooled controls. RESULTS: In multi-arm platform trials with staggered entry, analyses adjusting for temporal drift (either Bayesian or frequentist) have superior estimation of treatment effects and favorable testing properties compared to analyses using either concurrent or pooled controls. The Bayesian Time Machine generally provides estimates with greater precision and smaller mean square error than alternative approaches, at the risk of small bias and small Type I error inflation. CONCLUSIONS: The Bayesian Time Machine provides a compromise between bias and precision by smoothing estimates across time and leveraging all available data for the estimation of treatment effects. Prior distributions controlling the behavior of dynamic smoothing across time must be pre-specified and carefully calibrated to the unique context of each trial, appropriately accounting for the population, disease, and endpoints.


Assuntos
Projetos de Pesquisa , Teorema de Bayes , Viés , Protocolos Clínicos , Simulação por Computador , Humanos
12.
JAMA ; 327(3): 227-236, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-35040887

RESUMO

Importance: Platelets represent a potential therapeutic target for improved clinical outcomes in patients with COVID-19. Objective: To evaluate the benefits and risks of adding a P2Y12 inhibitor to anticoagulant therapy among non-critically ill patients hospitalized for COVID-19. Design, Setting, and Participants: An open-label, bayesian, adaptive randomized clinical trial including 562 non-critically ill patients hospitalized for COVID-19 was conducted between February 2021 and June 2021 at 60 hospitals in Brazil, Italy, Spain, and the US. The date of final 90-day follow-up was September 15, 2021. Interventions: Patients were randomized to a therapeutic dose of heparin plus a P2Y12 inhibitor (n = 293) or a therapeutic dose of heparin only (usual care) (n = 269) in a 1:1 ratio for 14 days or until hospital discharge, whichever was sooner. Ticagrelor was the preferred P2Y12 inhibitor. Main Outcomes and Measures: The composite primary outcome was organ support-free days evaluated on an ordinal scale that combined in-hospital death (assigned a value of -1) and, for those who survived to hospital discharge, the number of days free of respiratory or cardiovascular organ support up to day 21 of the index hospitalization (range, -1 to 21 days; higher scores indicate less organ support and better outcomes). The primary safety outcome was major bleeding by 28 days as defined by the International Society on Thrombosis and Hemostasis. Results: Enrollment of non-critically ill patients was discontinued when the prespecified criterion for futility was met. All 562 patients who were randomized (mean age, 52.7 [SD, 13.5] years; 41.5% women) completed the trial and 87% received a therapeutic dose of heparin by the end of study day 1. In the P2Y12 inhibitor group, ticagrelor was used in 63% of patients and clopidogrel in 37%. The median number of organ support-free days was 21 days (IQR, 20-21 days) among patients in the P2Y12 inhibitor group and was 21 days (IQR, 21-21 days) in the usual care group (adjusted odds ratio, 0.83 [95% credible interval, 0.55-1.25]; posterior probability of futility [defined as an odds ratio <1.2], 96%). Major bleeding occurred in 6 patients (2.0%) in the P2Y12 inhibitor group and in 2 patients (0.7%) in the usual care group (adjusted odds ratio, 3.31 [95% CI, 0.64-17.2]; P = .15). Conclusions and Relevance: Among non-critically ill patients hospitalized for COVID-19, the use of a P2Y12 inhibitor in addition to a therapeutic dose of heparin, compared with a therapeutic dose of heparin only, did not result in an increased odds of improvement in organ support-free days within 21 days during hospitalization. Trial Registration: ClinicalTrials.gov Identifier: NCT04505774.


Assuntos
Anticoagulantes/administração & dosagem , Tratamento Farmacológico da COVID-19 , Heparina/administração & dosagem , Pacientes Internados , Antagonistas do Receptor Purinérgico P2Y/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/efeitos adversos , COVID-19/sangue , COVID-19/mortalidade , Clopidogrel/administração & dosagem , Clopidogrel/efeitos adversos , Comorbidade , Oxigenação por Membrana Extracorpórea/estatística & dados numéricos , Feminino , Hemorragia/induzido quimicamente , Heparina/efeitos adversos , Mortalidade Hospitalar , Humanos , Masculino , Futilidade Médica , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Oxigenoterapia/estatística & dados numéricos , Ativação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/efeitos adversos , Antagonistas do Receptor Purinérgico P2Y/efeitos adversos , Receptores Purinérgicos P2Y12 , Respiração Artificial/estatística & dados numéricos , Trombose/epidemiologia , Ticagrelor/administração & dosagem , Ticagrelor/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
13.
Gut ; 70(10): 1894-1903, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-32933947

RESUMO

OBJECTIVE: To describe the clinical, pathological and genomic characteristics of pancreatic cancer with DNA mismatch repair deficiency (MMRD) and proficiency (MMRP). DESIGN: We identified patients with MMRD and MMRP pancreatic cancer in a clinical cohort (N=1213, 519 with genetic testing, 53 with immunohistochemistry (IHC)) and a genomic cohort (N=288 with whole-genome sequencing (WGS)). RESULTS: 12 out of 1213 (1.0%) in the clinical cohort were MMRD by IHC or WGS. Of the 14 patients with Lynch syndrome, 3 (21.4%) had an MMRP pancreatic cancer by IHC, and 4 (28.6%) were excluded because tissue was unavailable for testing. MMRD cancers had longer overall survival after surgery (weighted HR after coarsened exact matching 0.11, 95% CI 0.02 to 0.78, p=0.001). One patient with an unresectable MMRD cancer has an ongoing partial response 3 years after starting treatment with PD-L1/CTLA-4 inhibition. This tumour showed none of the classical histopathological features of MMRD. 9 out of 288 (3.1%) tumours with WGS were MMRD. Despite markedly higher tumour mutational burden and neoantigen loads, MMRD cancers were significantly less likely to have mutations in usual pancreatic cancer driver genes like KRAS and SMAD4, but more likely to have mutations in genes that drive cancers with microsatellite instability like ACV2RA and JAK1. MMRD tumours were significantly more likely to have a basal-like transcriptional programme and elevated transcriptional markers of immunogenicity. CONCLUSIONS: MMRD pancreatic cancers have distinct clinical, pathological and genomic profiles. Patients with MMRD pancreatic cancer should be considered for basket trials targeting enhanced immunogenicity or the unique genomic drivers in these malignancies.


Assuntos
Adenocarcinoma/genética , Distúrbios no Reparo do DNA/genética , Neoplasias Pancreáticas/genética , Adenocarcinoma/patologia , Neoplasias Colorretais Hereditárias sem Polipose/genética , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Distúrbios no Reparo do DNA/patologia , Feminino , Testes Genéticos , Genômica , Humanos , Masculino , Instabilidade de Microssatélites , Mutação , Ontário , Neoplasias Pancreáticas/patologia , Estudos Retrospectivos , Sequenciamento Completo do Genoma
14.
Genet Med ; 23(11): 2067-2075, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34257421

RESUMO

PURPOSE: To evaluate the safety and efficacy of N-acetylmannosamine (ManNAc) in GNE myopathy, a genetic muscle disease caused by deficiency of the rate-limiting enzyme in N-acetylneuraminic acid (Neu5Ac) biosynthesis. METHODS: We conducted an open-label, phase 2, single-center (NIH, USA) study to evaluate oral ManNAc in 12 patients with GNE myopathy (ClinicalTrials.gov NCT02346461). Primary endpoints were safety and biochemical efficacy as determined by change in plasma Neu5Ac and sarcolemmal sialylation. Clinical efficacy was evaluated using secondary outcome measures as part of study extensions, and a disease progression model (GNE-DPM) was tested as an efficacy analysis method. RESULTS: Most drug-related adverse events were gastrointestinal, and there were no serious adverse events. Increased plasma Neu5Ac (+2,159 nmol/L, p < 0.0001) and sarcolemmal sialylation (p = 0.0090) were observed at day 90 compared to baseline. A slower rate of decline was observed for upper extremity strength (p = 0.0139), lower extremity strength (p = 0.0006), and the Adult Myopathy Assessment Tool (p = 0.0453), compared to natural history. Decreased disease progression was estimated at 12 (γ = 0.61 [95% CI: 0.09, 1.27]) and 18 months (γ = 0.55 [95% CI: 0.12, 1.02]) using the GNE-DPM. CONCLUSION: ManNAc showed long-term safety, biochemical efficacy consistent with the intended mechanism of action, and preliminary evidence clinical efficacy in patients with GNE myopathy.


Assuntos
Miopatias Distais , Doenças Musculares , Adulto , Hexosaminas , Humanos , Doenças Musculares/induzido quimicamente , Doenças Musculares/tratamento farmacológico , Doenças Musculares/genética , Ácido N-Acetilneuramínico
15.
Stat Med ; 40(19): 4167-4184, 2021 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-33960507

RESUMO

A Bayesian adaptive design is proposed for a clinical trial in Duchenne muscular dystrophy. The trial was designed to demonstrate treatment efficacy on an ambulatory-based clinical endpoint and to identify early success on a biomarker (dystrophin protein levels) that can serve as a basis for accelerated approval in the United States. The trial incorporates placebo augmentation using placebo data from past clinical trials. A thorough simulation study was conducted to understand the operating characteristics of the trial. This trial design was selected for the US FDA Complex Innovative Trial Design Pilot Meeting Program and the experience in that program is summarized.


Assuntos
Distrofia Muscular de Duchenne , Teorema de Bayes , Distrofina , Humanos , Distrofia Muscular de Duchenne/tratamento farmacológico , Projetos de Pesquisa , Resultado do Tratamento
16.
BMC Infect Dis ; 21(1): 1170, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34800996

RESUMO

BACKGROUND: Convalescent plasma has been widely used to treat COVID-19 and is under investigation in numerous randomized clinical trials, but results are publicly available only for a small number of trials. The objective of this study was to assess the benefits of convalescent plasma treatment compared to placebo or no treatment and all-cause mortality in patients with COVID-19, using data from all available randomized clinical trials, including unpublished and ongoing trials (Open Science Framework, https://doi.org/10.17605/OSF.IO/GEHFX ). METHODS: In this collaborative systematic review and meta-analysis, clinical trial registries (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform), the Cochrane COVID-19 register, the LOVE database, and PubMed were searched until April 8, 2021. Investigators of trials registered by March 1, 2021, without published results were contacted via email. Eligible were ongoing, discontinued and completed randomized clinical trials that compared convalescent plasma with placebo or no treatment in COVID-19 patients, regardless of setting or treatment schedule. Aggregated mortality data were extracted from publications or provided by investigators of unpublished trials and combined using the Hartung-Knapp-Sidik-Jonkman random effects model. We investigated the contribution of unpublished trials to the overall evidence. RESULTS: A total of 16,477 patients were included in 33 trials (20 unpublished with 3190 patients, 13 published with 13,287 patients). 32 trials enrolled only hospitalized patients (including 3 with only intensive care unit patients). Risk of bias was low for 29/33 trials. Of 8495 patients who received convalescent plasma, 1997 died (23%), and of 7982 control patients, 1952 died (24%). The combined risk ratio for all-cause mortality was 0.97 (95% confidence interval: 0.92; 1.02) with between-study heterogeneity not beyond chance (I2 = 0%). The RECOVERY trial had 69.8% and the unpublished evidence 25.3% of the weight in the meta-analysis. CONCLUSIONS: Convalescent plasma treatment of patients with COVID-19 did not reduce all-cause mortality. These results provide strong evidence that convalescent plasma treatment for patients with COVID-19 should not be used outside of randomized trials. Evidence synthesis from collaborations among trial investigators can inform both evidence generation and evidence application in patient care.


Assuntos
COVID-19 , COVID-19/terapia , Humanos , Imunização Passiva , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2 , Resultado do Tratamento , Soroterapia para COVID-19
17.
Cancer ; 126(7): 1530-1540, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31860138

RESUMO

BACKGROUND: Globally, the rising cost of anticancer therapy has motivated efforts to quantify the overall value of new cancer treatments. Multicriteria decision analysis offers a novel approach to incorporate multiple criteria and perspectives into value assessment. METHODS: The authors recruited a diverse, multistakeholder group who identified and weighted key criteria to establish the drug assessment framework (DAF). Construct validity assessed the degree to which DAF scores were associated with past pan-Canadian Oncology Drug Review (pCODR) funding recommendations and European Society for Medical Oncology Magnitude of Clinical Benefit Scale (ESMO-MCBS; version 1.1) scores. RESULTS: The final DAF included 10 criteria: overall survival, progression-free survival, response rate, quality of life, toxicity, unmet need, equity, feasibility, disease severity, and caregiver well-being. The first 5 clinical benefit criteria represent approximately 64% of the total weight. DAF scores ranged from 0 to 300, reflecting both the expected impact of the drug and the quality of supporting evidence. When the DAF was applied to the last 60 drugs (with reviewers blinded) reviewed by pCODR (2015-2018), those drugs with positive pCODR funding recommendations were found to have higher DAF scores compared with drugs not recommended (103 vs 63; Student t test P = .0007). DAF clinical benefit criteria mildly correlated with ESMO-MCBS scores (correlation coefficient, 0.33; 95% CI, 0.009-0.59). Sensitivity analyses that varied the criteria scores did not change the results. CONCLUSIONS: Using a structured and explicit approach, a criterion-based valuation framework was designed to provide a transparent and consistent method with which to value and prioritize cancer drugs to facilitate the delivery of affordable cancer care.


Assuntos
Antineoplásicos/economia , Análise Custo-Benefício/métodos , Oncologia/economia , Canadá , Humanos
18.
Clin Trials ; 17(5): 491-500, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32815416

RESUMO

BACKGROUND: Mortality from COVID-19 is high among hospitalized patients and effective therapeutics are lacking. Hypercoagulability, thrombosis and hyperinflammation occur in COVID-19 and may contribute to severe complications. Therapeutic anticoagulation may improve clinical outcomes through anti-thrombotic, anti-inflammatory and anti-viral mechanisms. Our primary objective is to evaluate whether therapeutic-dose anticoagulation with low-molecular-weight heparin or unfractionated heparin prevents mechanical ventilation and/or death in patients hospitalized with COVID-19 compared to usual care. METHODS: An international, open-label, adaptive randomized controlled trial. Using a Bayesian framework, the trial will declare results as soon as pre-specified posterior probabilities for superiority, futility, or harm are reached. The trial uses response-adaptive randomization to maximize the probability that patients will receive the more beneficial treatment approach, as treatment effect information accumulates within the trial. By leveraging a common data safety monitoring board and pooling data with a second similar international Bayesian adaptive trial (REMAP-COVID anticoagulation domain), treatment efficacy and safety will be evaluated as efficiently as possible. The primary outcome is an ordinal endpoint with three possible outcomes based on the worst status of each patient through day 30: no requirement for invasive mechanical ventilation, invasive mechanical ventilation or death. CONCLUSION: Using an adaptive trial design, the Anti-Thrombotic Therapy To Ameliorate Complications of COVID-19 trial will establish whether therapeutic anticoagulation can reduce mortality and/or avoid the need for mechanical ventilation in patients hospitalized with COVID-19. Leveraging existing networks to recruit sites will increase enrollment and mitigate enrollment risk in sites with declining COVID-19 cases.


Assuntos
Antivirais/uso terapêutico , Betacoronavirus , Infecções por Coronavirus/tratamento farmacológico , Heparina/administração & dosagem , Pneumonia Viral/tratamento farmacológico , Trombose/prevenção & controle , Adolescente , Adulto , Anticoagulantes/administração & dosagem , COVID-19 , Infecções por Coronavirus/complicações , Infecções por Coronavirus/epidemiologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , SARS-CoV-2 , Trombose/etiologia , Resultado do Tratamento , Adulto Jovem
19.
Anal Chem ; 91(18): 11848-11855, 2019 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-31411020

RESUMO

The extraction of bioanalytes is the first step in many diagnostic and analytical assays. However, most bioanalyte extraction methods require extensive dilution-based washing processes that are not only time-consuming and laborious but can also result in significant sample loss, limiting their applications in rare sample analyses. Here, we present a method that enables the efficient extraction of multiple different bioanalytes from rare samples (down to 10 cells) without washing-centrifugation-assisted immiscible fluid filtration (CIFF). CIFF utilizes centrifugal force to drive the movement of analyte-bound glass microbeads from an aqueous sample into an immiscible hydrophobic solution to perform an efficient, simple, and nondilutive extraction. The method can be performed using conventional polymerase chain reaction (PCR) tubes with no requirement of specialized devices, columns, or instruments, making it broadly accessible and cost-effective. The CIFF process can effectively remove approximately 99.5% of the aqueous sample in one extraction with only 0.5% residual carryover, whereas a traditional "spin-down and aspirate" operation results in a higher 3.6% carryover. Another unique aspect of CIFF is its ability to perform two different solid-phase bioanalytes extractions simultaneously within a single vessel without fractionating the sample or performing serial extractions. Here we demonstrate efficient mRNA and DNA extraction from low-input samples (down to 10 cells) with slightly higher to comparable recovery compared to a traditional column-based extraction technique and the simultaneous extraction of two different proteins in the same tube using CIFF.


Assuntos
Centrifugação/métodos , Fracionamento Químico/métodos , DNA/isolamento & purificação , Filtração/métodos , RNA Mensageiro/isolamento & purificação , Fracionamento Químico/instrumentação , Humanos , Reação em Cadeia da Polimerase/instrumentação , Proteínas/isolamento & purificação , Propriedades de Superfície , Células THP-1
20.
Stat Med ; 38(17): 3123-3138, 2019 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-31070807

RESUMO

A primary goal of a phase II dose-ranging trial is to identify a correct dose before moving forward to a phase III confirmatory trial. A correct dose is one that is actually better than control. A popular model in phase II is an independent model that puts no structure on the dose-response relationship. Unfortunately, the independent model does not efficiently use information from related doses. One very successful alternate model improves power using a pre-specified dose-response structure. Past research indicates that EMAX models are broadly successful and therefore attractive for designing dose-response trials. However, there may be instances of slight risk of nonmonotone trends that need to be addressed when planning a clinical trial design. We propose to add hierarchical parameters to the EMAX model. The added layer allows information about the treatment effect in one dose to be "borrowed" when estimating the treatment effect in another dose. This is referred to as the hierarchical EMAX model. Our paper compares three different models (independent, EMAX, and hierarchical EMAX) and two different design strategies. The first design considered is Bayesian with a fixed trial design, and it has a fixed schedule for randomization. The second design is Bayesian but adaptive, and it uses response adaptive randomization. In this article, a randomized trial of patients with severe traumatic brain injury is provided as a motivating example.


Assuntos
Ensaios Clínicos Fase II como Assunto , Relação Dose-Resposta a Droga , Oxigenoterapia Hiperbárica , Modelos Estatísticos , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Teorema de Bayes , Humanos , Estudos Multicêntricos como Assunto , Estudos Prospectivos
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