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OBJECTIVES: The goal of the research was to assess the quantitative relationship between median progression-free survival (PFS) and median overall survival (OS) specifically among patients with relapsed/refractory multiple myeloma (RRMM) based on published randomized controlled trials (RCTs). METHODS: Two bibliographic databases (PubMed and Embase, 1970-2017) were systematically searched for RCTs in RRMM that reported OS and PFS, followed by an updated search of studies published between 2010 and 2022 in 3 databases (Embase, MEDLINE, and EBM Reviews, 2010-2022). The association between median PFS and median OS was assessed using the nonparametric Spearman rank and parametric Pearson correlation coefficients. Subsequently, the quantitative relationship between PFS and OS was assessed using weighted least-squares regression adjusted for covariates including age, sex, and publication year. Study arms were weighted by the number of patients in each arm. RESULTS: A total of 31 RCTs (56 treatment arms, 10,450 patients with RRMM) were included in the analysis. The average median PFS and median OS were 7.1 months (SD 5.5) and 28.1 months (SD 11.8), respectively. The Spearman and Pearson correlation coefficients between median PFS and median OS were 0.80 (P < 0.0001) and 0.79 (P < 0.0001), respectively. In individual treatment arms of RRMM trials, each 1-month increase in median PFS was associated with a 1.72-month (95% CI 1.26-2.17) increase in median OS. CONCLUSION: Analysis of the relationship between PFS and OS incorporating more recent studies in RRMM further substantiates the use of PFS to predict OS in RRMM.
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Mieloma Múltiplo , Intervalo Livre de Progressão , Ensaios Clínicos Controlados Aleatórios como Assunto , Mieloma Múltiplo/mortalidade , Mieloma Múltiplo/terapia , Mieloma Múltiplo/patologia , Humanos , Recidiva Local de Neoplasia/mortalidade , Feminino , MasculinoRESUMO
Aim: The correlation between response and survival has not been well-studied in relapsed or refractory multiple myeloma (RRMM). Materials & methods: A systematic literature review of Medline, Embase and Cochrane databases (2010-06/2020) and relevant congresses (2018-2020) was performed to identify randomized clinical trials in RRMM reporting median overall survival (mOS), progression-free survival and response end points. The relationship between mOS and response end points was analyzed using Pearson's product-moment correlation. Results: A total of 81 records for 65 original studies, representing 12,827 patients were included. The correlation was moderate for mOS with overall response rate (Pearson r = 0.79), very good partial response (r = 0.73) and duration of response (r = 0.78); all were statistically significant. In linear regression models, estimated mOS gain was 0.48, 0.47 and 1.94 months per percentage point of overall response rate, very good partial response and complete response, respectively (all p < 0.001). Significance was maintained after adjustment for age, relapsed versus refractory multiple myeloma and study year. The analysis was limited by small sample sizes and inconsistent reporting of study-level covariates. Conclusion: These findings support short-term response-based end points as surrogates to survival in RRMM.
Treatments for multiple myeloma may not work for every patient and the cancer may come back. In clinical trials, it is difficult to find out how well new treatments work in allowing patients to live longer. This is especially true when patients have advanced disease that has returned or has not responded to treatment. How well a patient responds to treatment (i.e., has a decreased extent of disease) could indicate whether the drug will help the patient live longer, but the relationship between response to treatment and survival is not fully understood. We conducted a systematic review and meta-analysis to better understand how response rates and survival are related. A systematic review collects all the published research on a specific subject, and a meta-analysis is a statistical method that creates a single finding from several separate studies. This study found a moderate relationship between how long patients live after receiving treatment for multiple myeloma and their response to treatment. This would allow response-to-treatment data from clinical trials to be used to predict better survival and show the drug can help patients.
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Mieloma Múltiplo , Humanos , Mieloma Múltiplo/tratamento farmacológico , Indução de Remissão , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Dexametasona/uso terapêuticoRESUMO
BACKGROUND: Digital therapeutics (DTx), a class of software-based clinical interventions, are promising new technologies that can potentially prevent, manage, or treat a spectrum of medical disorders and diseases as well as deliver unprecedented portability for patients and scalability for health care providers. Their adoption and implementation were accelerated by the need for remote care during the COVID-19 pandemic, and awareness about their utility has rapidly grown among providers, payers, and regulators. Despite this, relatively little is known about the capacity of DTx to provide economic value in care. OBJECTIVE: This study aimed to systematically review and summarize the published evidence regarding the cost-effectiveness of clinical-grade mobile app-based DTx and explore the factors affecting such evaluations. METHODS: A systematic review of economic evaluations of clinical-grade mobile app-based DTx was conducted following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 guidelines. Major electronic databases, including PubMed, Cochrane Library, and Web of Science, were searched for eligible studies published from inception to October 28, 2022. Two independent reviewers evaluated the eligibility of all the retrieved articles for inclusion in the review. Methodological quality and risk of bias were assessed for each included study. RESULTS: A total of 18 studies were included in this review. Of the 18 studies, 7 (39%) were nonrandomized study-based economic evaluations, 6 (33%) were model-based evaluations, and 5 (28%) were randomized clinical trial-based evaluations. The DTx intervention subject to assessment was found to be cost-effective in 12 (67%) studies, cost saving in 5 (28%) studies, and cost-effective in 1 (6%) study in only 1 of the 3 countries where it was being deployed in the final study. Qualitative deficiencies in methodology and substantial potential for bias, including risks of performance bias and selection bias in participant recruitment, were identified in several included studies. CONCLUSIONS: This systematic review supports the thesis that DTx interventions offer potential economic benefits. However, DTx economic analyses conducted to date exhibit important methodological shortcomings that must be addressed in future evaluations to reduce the uncertainty surrounding the widespread adoption of DTx interventions. TRIAL REGISTRATION: PROSPERO International Prospective Register of Systematic Reviews CRD42022358616; https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42022358616.
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COVID-19 , Aplicativos Móveis , Humanos , Análise Custo-Benefício , Pandemias , Ensaios Clínicos como AssuntoRESUMO
Aims: To compare clinical trial results for crizotinib and entrectinib in ROS1-positive non-small-cell lung cancer and compare clinical trial data and real-world outcomes for crizotinib. Patients & methods: We analyzed four phase I-II studies using a simulated treatment comparison (STC). A STC of clinical trial versus real-world evidence compared crizotinib clinical data to real-world outcomes. Results: Adjusted STC found nonsignificant trends favoring crizotinib over entrectinib: objective response rate, risk ratio = 1.04 (95% CI: 0.85-1.28); median duration of response, mean difference = 16.11 months (95% CI: -1.57- 33.69); median progression-free survival, mean difference = 3.99 months (95% CI: -6.27-14.25); 12-month overall survival, risk ratio = 1.01 (95% CI: 0.90-1.12). Nonsignificant differences were observed between the trial end point values and the real-world evidence for crizotinib. Conclusions: Crizotinib and entrectinib have comparable efficacy in ROS1-positive non-small-cell lung cancer.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Inibidores de Proteínas Quinases , Benzamidas/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Ensaios Clínicos como Assunto , Crizotinibe/uso terapêutico , Humanos , Indazóis/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Inibidores de Proteínas Quinases/uso terapêutico , Proteínas Tirosina Quinases/genética , Proteínas Tirosina Quinases/uso terapêutico , Proteínas Proto-Oncogênicas/genética , Resultado do TratamentoRESUMO
BACKGROUND: Selinexor is an oral, selective nuclear export inhibitor. STORM was a phase 2b, single-arm, open-label, multicenter trial of selinexor with low dose dexamethasone in patients with penta-exposed relapsed/refractory multiple myeloma (RRMM) that met its primary endpoint, with overall response of 26% (95% confidence interval [CI], 19 to 35%). Health-related quality of life (HRQoL) was a secondary endpoint measured using the Functional Assessment of Cancer Therapy - Multiple Myeloma (FACT-MM). This study examines impact of selinexor treatment on HRQoL of patients treated in STORM and reports two approaches to calculate minimal clinically important differences for the FACT-MM. METHODS: FACT-MM data were collected at baseline, on day 1 of each 4-week treatment cycle, and at end of treatment (EOT). Changes from baseline were analyzed for the FACT-MM total score, FACT-trial outcome index (TOI), FACT-General (FACT-G), and the MM-specific domain using mixed-effects regression models. Two approaches for evaluating minimal clinically important differences were explored: the first defined as 10% of the instrument range, and the second based on estimated mean baseline differences between Eastern Cooperative Oncology Group performance status (ECOG PS) scores. Post-hoc difference analysis compared change in scores from baseline to EOT for treatment responders and non-responders. RESULTS: Eighty patients were included in the analysis; the mean number of prior therapies was 7.9 (standard deviation [SD] 3.1), and mean duration of myeloma was 7.6 years (SD 3.4). Each exploratory minimal clinically important difference threshold yielded consistent results whereby most patients did not experience HRQoL decline during the first six cycles of treatment (range: 53.9 to 75.7% for the first approach; range: 52.6 to 72.9% for the second). Treatment responders experienced less decline in HRQoL from baseline to EOT than non-responders, which was significant for the FACT-G, but not for other scores. CONCLUSION: The majority of patients did not experience decline in HRQoL based on minimal clinically important differences during early cycles of treatment with selinexor and dexamethasone in the STORM trial. An anchor-based approach utilizing patient-level data (ECOG PS score) to define minimal clinically important differences for the FACT-MM gave consistent results with a distribution-based approach. TRIAL REGISTRATION: This trial was registered on ClinicalTrials.gov under the trial-ID NCT02336815 on January 8, 2015.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Mieloma Múltiplo/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Qualidade de Vida , Adulto , Idoso , Idoso de 80 Anos ou mais , Dexametasona/administração & dosagem , Feminino , Seguimentos , Humanos , Hidrazinas/administração & dosagem , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/patologia , Recidiva Local de Neoplasia/patologia , Prognóstico , Taxa de Sobrevida , Triazóis/administração & dosagemRESUMO
Aim: Evaluate health-related quality of life (HRQoL) and health utility impact of single-agent selinexor in heavily pretreated patients with relapsed/refractory diffuse large B-cell lymphoma. Patients & methods: Functional Assessment of Cancer Therapy (FACT) - Lymphoma and EuroQoL five-dimensions five-levels data collected in the single-arm Phase IIb trial SADAL (NCT02227251) were analyzed with mixed-effects models. Results: Treatment responders maintained higher FACT - Lymphoma (p ≤ 0.05), FACT - General (p < 0.05) and EuroQoL five-dimensions five-levels index scores (p < 0.001) beginning in cycle 3. The estimated difference in health state utilities for treatment response and progressive disease was both statistically significant and clinically meaningful (mean difference: 0.07; p = 0.001). Conclusion: In patients with relapsed/refractory diffuse large B-cell lymphoma, objective response to selinexor was associated with HRQoL maintenance, reduction in disease-related HRQoL decrements and higher health utilities.
Lay abstract This work examined quality of life (QoL) among patients with relapsed/refractory diffuse large B-cell lymphoma with two to five prior therapies who received single-agent selinexor in the SADAL clinical trial. Analysis of patient-reported Functional Assessment of Cancer Therapy Lymphoma and EuroQoL five-dimensions five-levels data showed that patients who had objective clinical response to selinexor maintained their QoL over the course of treatment. Grade ≥3 adverse events and serious adverse events were not associated with clinically meaningful negative QoL impacts. Clinical trial registration: NCT02227251 (ClinicalTrials.gov).
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Hidrazinas/uso terapêutico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Triazóis/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Linfoma Difuso de Grandes Células B/patologia , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , RecidivaRESUMO
BACKGROUND: In the Phase 3 REFLECT trial in patients with unresectable hepatocellular carcinoma (uHCC), the multitargeted tyrosine kinase inhibitor, lenvatinib, was noninferior to sorafenib in the primary outcome of overall survival. Post-hoc review revealed imbalances in prognostic variables between treatment arms. Here, we re-analyse overall survival data from REFLECT to adjust for the imbalance in covariates. METHODS: Univariable and multivariable adjustments were undertaken for a candidate set of covariate values that a physician panel indicated could be prognostically associated with overall survival in uHCC. The values included baseline variables observed pre- and post-randomisation. Univariable analyses were based on a stratified Cox model. The multivariable analysis used a "forwards stepwise" Cox model. RESULTS: Univariable analysis identified alpha-fetoprotein (AFP) as the most influential variable. The chosen multivariable Cox model analysis resulted in an estimated adjusted hazard ratio for lenvatinib of 0.814 (95% CI: 0.699-0.948) when only baseline variables were included. Adjusting for post-randomisation treatment variables further increased the estimated superiority of lenvatinib. CONCLUSIONS: Covariate adjustment of REFLECT suggests that the original noninferiority trial likely underestimated the true effect of lenvatinib on overall survival due to an imbalance in baseline prognostic covariates and the greater use of post-treatment therapies in the sorafenib arm. TRIAL REGISTRATION: Trial number: NCT01761266 (Submitted January 2, 2013).
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Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Compostos de Fenilureia/uso terapêutico , Quinolinas/uso terapêutico , Sorafenibe/uso terapêutico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Fatores de RiscoRESUMO
BACKGROUND: The World Health Organisation recommended dolutegravir (DTG)-based antiretroviral therapy (ART) regimens are available but not reimbursed through the public reimbursement system in China. The objective of this analysis was to evaluate the cost-effectiveness of DTG (DTG + TDF/3TC) compared to efavirenz (EFV + TDF/3TC) in treatment-naive and ritonavir-boosted lopinavir (LPV/r + TDF/3TC) in first-line ART failure HIV-1-infected patients in China. METHODS: A dynamic Markov model comprising of 5 response states and 6 CD4+ count-based health states was used. Efficacy, estimated as probability of virologic suppression (HIV RNA < 50 copies/mL) at 48 weeks, was obtained from a published network meta-analysis for ART-naive patients and from the DAWNING study for patients failing first-line ART. Baseline cohort characteristics were informed using DTG phase 3 studies and the DAWNING study data, respectively. Health state utilities were derived from DTG phase 3 studies. A 5-year cost-effectiveness analyses was conducted using the societal perspective. Outcomes were quality-adjusted-life-years (QALYs), life-years (LYs), incremental cost per QALYs (ICER). RESULTS: The viral suppression rates for DTG + TDF/3TC were higher than EFV + TDF/3TC (75.3% vs 64.0%) in treatment-naive and LPV/r + TDF/3TC (74.8% vs 58.4%) in first-line ART failure patients. This resulted in higher QALYs for DTG + TDF/3TC in treatment-naive (4.232 vs 4.227) and first-line failure settings (4.224 vs 4.221). Total discounted cost for DTG + TDF/3TC patients (RMB 219.259 in treatment-naive and RMB 238,746 in first-line failures) were lower than comparators (EFV + TDF/3TC:RMB 221,605; LPV/r + TDF/3TC:RMB 244,364), thereby DTG dominated in both settings. Probabilistic sensitivity analyses indicated the probability of DTG + TDF/3TC being cost effective was 98.2% in treatment-naive setting and 100% in first-line failure setting at a willingness to pay threshold of RMB 100,000/QALY. CONCLUSIONS: With lower costs, higher response rates and higher QALYs, DTG + TDF/3TC can be considered as a cost-effective alternative for treatment naive and first-line failure patients in China.
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AIMS: Midostaurin (MIDO) has been proposed for the treatment of newly-diagnosed adult patients with FMS-like tyrosine kinase 3 mutation-positive (FLT3+) acute myeloid leukemia (AML) in combination with standard chemotherapy. The cost-effectiveness of MIDO and standard of care (SOC) followed by MIDO monotherapy was compared to SOC alone for newly-diagnosed FLT3+ AML in the UK. METHODS: A partitioned survival model was developed from a UK public healthcare system perspective to compare the cost-effectiveness of MIDO plus SOC and SOC over a lifetime horizon. The model included the following health states/partitions: induction, consolidation, monotherapy, complete remission (CR), relapse, stem cell transplantation (SCT), SCT recovery, and post-SCT recovery. Data on CR, overall survival, and adverse events were obtained from a Phase III clinical trial. Overall survival was extrapolated beyond the trial horizon using a 'cure model' approach and data from the Office for National Statistics. Utilities were identified via a systematic review. Routine care utilization was obtained from the National Institute for Health and Care Excellence single technology appraisal for azacitidine in AML (TA399). The costs of drugs and administration, adverse events, hospitalizations, physician visits, and end-of-life care were incorporated. RESULTS: Incremental life years (LYs) and quality-adjusted life years (QALYs) gained by patients on MIDO and SOC versus SOC were 1.67 and 1.47, respectively. At an incremental cost of £54,072 over a lifetime horizon, the ICER was £32,465 per LY and £36,826 per QALY. Sensitivity analyses were generally consistent with the base case findings. CONCLUSIONS: With limited treatments in FLT3+ AML, MIDO represents a clinically significant advance in the management of newly-diagnosed AML. Using a threshold of £50,000 per QALY for end-of-life treatment, MIDO was shown to be a cost-effective option for newly-diagnosed FLT3+ AML.
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BACKGROUND: Persistent seizures are associated with physical injury, reduced quality of life, and psychosocial impairment. Perampanel is approved for the adjunctive treatment of primary generalized tonic-clonic seizures (PGTCS). OBJECTIVE: This study aimed to determine the cost-effectiveness of perampanel as adjunctive therapy to other antiepileptic drugs (AED) compared with AED maintenance therapy alone for the treatment of PGTCS. METHODS: We developed a Markov model for PGTCS where transitions were based on treatment response rates. The analysis was conducted over a 33-year time horizon from the Spanish National Health Service (NHS) and societal perspectives. Efficacy data were derived from clinical studies. Resource use, market shares, costs, and utilities were obtained from Kantar Health's National Health and Wellness Survey. Drug costs were obtained from the Consejo General de Colegios Oficiales de Farmacéuticos. One-way and probabilistic sensitivity analyses were performed. RESULTS: In the base case analysis from the NHS perspective, perampanel was associated with an incremental cost-effectiveness ratio (ICER) of 16,557/quality-adjusted life year (QALY) relative to AED maintenance therapy for the treatment of PGTCS. Incremental costs were 5475 and incremental QALYs were 0.33. In one-way sensitivity analyses, the ICERs were strongly influenced by discounting rate for costs and health effects, with little influence of other parameters, including perampanel cost and utilities. In probabilistic sensitivity analyses, the probability of perampanel being cost-effective at a willingness-to-pay threshold of 30,000/QALY was 89.3%. From the societal perspective, perampanel provided a cost-savings of 5288 per patient compared with AED maintenance therapy alone. CONCLUSION: Our study demonstrates that perampanel is likely to be a cost-effective option.
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Anticonvulsivantes/economia , Anticonvulsivantes/uso terapêutico , Epilepsia Generalizada/tratamento farmacológico , Epilepsia Generalizada/economia , Epilepsia Tônico-Clônica/tratamento farmacológico , Epilepsia Tônico-Clônica/economia , Piridonas/economia , Piridonas/uso terapêutico , Convulsões/tratamento farmacológico , Convulsões/economia , Anticonvulsivantes/efeitos adversos , Análise Custo-Benefício , Epilepsia Generalizada/mortalidade , Epilepsia Tônico-Clônica/mortalidade , Humanos , Cadeias de Markov , Modelos Econômicos , Programas Nacionais de Saúde , Nitrilas , Piridonas/efeitos adversos , Qualidade de Vida , Anos de Vida Ajustados por Qualidade de Vida , Espanha/epidemiologiaRESUMO
PURPOSE: To evaluate the budget impact (BI) of adopting perampanel for adjunctive treatment of partial-onset seizures (POS), with or without secondarily generalized seizures, and the adjunctive treatment of primary generalized tonic-clonic seizures (PGTCS) in patients 12years or older in the United States. METHODS: A BI model was developed to estimate the potential BI of adopting adjunctive perampanel from a US payer (direct costs only) and societal (direct and indirect costs) perspective over a 5-year period. Efficacy data for perampanel and antiepileptic drug (AED) maintenance therapy were obtained from perampanel phase III clinical trials. Drug, direct medical (healthcare provider, emergency room, and hospitalizations), and indirect (productivity loss) costs were obtained from appropriate sources (e.g., AnalySource® Online [wholesale acquisition costs], 2013 Optum Insight Clinformatics Database [market share percentages, direct medical costs per unit], and 2011-2013 National Health and Wellness Survey [NHWS; healthcare resource utilization, overall work impairment, and baseline distribution of patients across the 4 health states]). Mapping of seizure frequency to medical resource utilization and work impairment was obtained from Kantar Health's NHWS. RESULTS: In a hypothetical health plan of 1 million members, 660 (0.066%) members ≥12years old had uncontrolled POS (395 [59.8%]) or PGTCS (265 [40.2%]). During the first 5years of adoption of perampanel, absolute BI (including drug, direct medical, and indirect costs) was $852, $2124, $3855, $5318, and $6397, respectively, for a cumulative absolute BI of $18,545. Drug cost was estimated to increase by $13,888, $34,646, $62,863, $86,728, and $104,326, respectively; however, this cost would be mostly offset by decreases in direct medical ($5041, $12,576, $22,818, $31,481, and $37,869, respectively) and indirect ($7995, $19,946, $36,190, $49,929, and $60,060, respectively) costs. Total per-member-per-month cost (drug and direct medical costs) was estimated to increase by $0.0007, $0.0018, $0.0033, $0.0046, and $0.0055 from years 1 to 5. CONCLUSIONS: Based on results of this BI model, increased cost of adopting perampanel in a health plan of 1 million members would be minimal for payers, and societal costs would be close to neutral.
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Anticonvulsivantes/economia , Modelos Econômicos , Piridonas/economia , Convulsões/tratamento farmacológico , Anticonvulsivantes/uso terapêutico , Bases de Dados Factuais , Quimioterapia Combinada , Feminino , Inquéritos Epidemiológicos , Hospitalização , Humanos , Masculino , Nitrilas , Piridonas/uso terapêutico , Estados UnidosRESUMO
Homogalacturonan pectin domains are synthesized in a highly methyl-esterified form that later can be differentially demethyl esterified by pectin methyl esterase (PME) to strengthen or loosen plant cell walls that contain pectin, including seed coat mucilage, a specialized secondary cell wall of seed coat epidermal cells. As a means to identify the active PMEs in seed coat mucilage, we identified seven PMEs expressed during seed coat development. One of these, HIGHLY METHYL ESTERIFIED SEEDS (HMS), is abundant during mucilage secretion, peaking at 7 d postanthesis in both the seed coat and the embryo. We have determined that this gene is required for normal levels of PME activity and homogalacturonan methyl esterification in the seed. The hms-1 mutant displays altered embryo morphology and mucilage extrusion, both of which are a consequence of defects in embryo development. A significant decrease in the size of cells in the embryo suggests that the changes in embryo morphology are a consequence of lack of cell expansion. Progeny from a cross between hms-1 and the previously characterized PME inhibitor5 overexpression line suggest that HMS acts independently from other cell wall-modifying enzymes in the embryo. We propose that HMS is required for cell wall loosening in the embryo to facilitate cell expansion during the accumulation of storage reserves and that its role in the seed coat is masked by redundancy.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/embriologia , Arabidopsis/enzimologia , Hidrolases de Éster Carboxílico/metabolismo , Sementes/embriologia , Sementes/enzimologia , Anticorpos/metabolismo , Arabidopsis/genética , Fenômenos Biomecânicos , Tamanho Celular , Esterificação , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Mutagênese Insercional , Pectinas/metabolismo , Fenótipo , Mucilagem Vegetal/metabolismo , Plantas Geneticamente Modificadas , Sementes/genética , Sementes/ultraestruturaRESUMO
The secretion of cell wall polysaccharides through the trans-Golgi network (TGN) is required for plant cell elongation. However, the components mediating the post-Golgi secretion of pectin and hemicellulose, the two major cell wall polysaccharides, are largely unknown. We identified evolutionarily conserved YPT/RAB GTPase Interacting Protein 4a (YIP4a) and YIP4b (formerly YIP2), which form a TGN-localized complex with ECHIDNA (ECH) in Arabidopsis thaliana. The localization of YIP4 and ECH proteins at the TGN is interdependent and influences the localization of VHA-a1 and SYP61, which are key components of the TGN. YIP4a and YIP4b act redundantly, and the yip4a yip4b double mutants have a cell elongation defect. Genetic, biochemical, and cell biological analyses demonstrate that the ECH/YIP4 complex plays a key role in TGN-mediated secretion of pectin and hemicellulose to the cell wall in dark-grown hypocotyls and in secretory cells of the seed coat. In keeping with these observations, Fourier transform infrared microspectroscopy analysis revealed that the ech and yip4a yip4b mutants exhibit changes in their cell wall composition. Overall, our results reveal a TGN subdomain defined by ECH/YIP4 that is required for the secretion of pectin and hemicellulose and distinguishes the role of the TGN in secretion from its roles in endocytic and vacuolar trafficking.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Parede Celular/metabolismo , Polissacarídeos/metabolismo , Rede trans-Golgi/metabolismo , Sequência de Aminoácidos , Arabidopsis/genética , Proteínas de Arabidopsis/classificação , Proteínas de Arabidopsis/genética , Parede Celular/genética , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microscopia Confocal , Dados de Sequência Molecular , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Mutação , Filogenia , Plantas Geneticamente Modificadas , Ligação Proteica , Homologia de Sequência de Aminoácidos , Técnicas do Sistema de Duplo-HíbridoRESUMO
MAIN CONCLUSION: Recent publications have increased our knowledge of how pectin composition and the degree of homogalacturonan methylesterification impact the biochemical and biomechanical properties of plant cell walls, plant development, and plants' interactions with their abiotic and biotic environments. Experimental observations have shown that the relationships between the DM, the pattern of de-methylesterificaton, its effect on cell wall elasticity, other biomechanical parameters, and growth are not straightforward. Working towards a detailed understanding of these relationships at single cell resolution is one of the big tasks of pectin research. Pectins are highly complex polysaccharides abundant in plant primary cell walls. New analytical and microscopy techniques are revealing the composition and mechanical properties of the cell wall and increasing our knowledge on the topic. Progress in plant physiological research supports a link between cell wall pectin modifications and plant development and interactions with the environment. Homogalacturonan pectins, which are major components of the primary cell wall, have a potential for modifications such as methylesterification, as well as an ability to form cross-linked structures with divalent cations. This contributes to changing the mechanical properties of the cell wall. This review aims to give a comprehensive overview of the pectin component homogalacturonan, including its synthesis, modification, regulation and role in the plant cell wall.
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Parede Celular/metabolismo , Pectinas/metabolismo , Fenômenos Biomecânicos , EsterificaçãoRESUMO
The methylesterification status of cell wall homogalacturonans, mediated through the action of pectin methylesterases (PMEs), influences the biophysical properties of plant cell walls such as elasticity and porosity, important parameters for cell elongation and water uptake. The completion of seed germination requires cell wall extensibility changes in both the radicle itself and in the micropylar tissues surrounding the radicle. In wild-type seeds of Arabidopsis (Arabidopsis thaliana), PME activities peaked around the time of testa rupture but declined just before the completion of germination (endosperm weakening and rupture). We overexpressed an Arabidopsis PME inhibitor to investigate PME involvement in seed germination. Seeds of the resultant lines showed a denser methylesterification status of their cell wall homogalacturonans, but there were no changes in the neutral sugar and uronic acid composition of the cell walls. As compared with wild-type seeds, the PME activities of the overexpressing lines were greatly reduced throughout germination, and the low steady-state levels neither increased nor decreased. The most striking phenotype was a significantly faster rate of germination, which was not connected to altered testa rupture morphology but to alterations of the micropylar endosperm cells, evident by environmental scanning electron microscopy. The transgenic seeds also exhibited an apparent reduced sensitivity to abscisic acid with respect to its inhibitory effects on germination. We speculate that PME activity contributes to the temporal regulation of radicle emergence in endospermic seeds by altering the mechanical properties of the cell walls and thereby the balance between the two opposing forces of radicle elongation and mechanical resistance of the endosperm.
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Arabidopsis/enzimologia , Hidrolases de Éster Carboxílico/metabolismo , Parede Celular/metabolismo , Germinação , Pectinas/metabolismo , Sementes/crescimento & desenvolvimento , Ácido Abscísico/metabolismo , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fenômenos Biomecânicos , Hidrolases de Éster Carboxílico/genética , Tamanho Celular , Ativação Enzimática , Esterificação , Flores/enzimologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Microscopia Eletrônica de Varredura , Fenótipo , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/genética , Sementes/enzimologia , Sementes/ultraestrutura , Ácidos Urônicos/metabolismoRESUMO
INTRODUCTION: Immunocompromised host pneumonia (ICHP) is an important cause of morbidity and mortality, yet usual care (UC) diagnostic tests often fail to identify an infectious etiology. A US-based, multicenter study (PICKUP) among ICHP patients with hematological malignancies, including hematological cell transplant recipients, showed that plasma microbial cell-free DNA (mcfDNA) sequencing provided significant additive diagnostic value. AIM: The objective of this study was to perform a cost-effectiveness analysis (CEA) of adding mcfDNA sequencing to UC diagnostic testing for hospitalized ICHP patients. METHODS: A semi-Markov model was utilized from the US third-party payer's perspective such that only direct costs were included, using a lifetime time horizon with discount rates of 3% for costs and benefits. Three comparators were considered: (1) All UC, which included non-invasive (NI) and invasive testing and early bronchoscopy; (2) All UC & mcfDNA; and (3) NI UC & mcfDNA & conditional UC Bronch (later bronchoscopy if the initial tests are negative). The model considered whether a probable causative infectious etiology was identified and if the patient received appropriate antimicrobial treatment through expert adjudication, and if the patient died in-hospital. The primary endpoints were total costs, life-years (LYs), equal value life-years (evLYs), quality-adjusted life-years (QALYs), and the incremental cost-effectiveness ratio per QALY. Extensive scenario and probabilistic sensitivity analyses (PSA) were conducted. RESULTS: At a price of $2000 (2023 USD) for the plasma mcfDNA, All UC & mcfDNA was more costly ($165,247 vs $153,642) but more effective (13.39 vs 12.47 LYs gained; 10.20 vs 9.42 evLYs gained; 10.11 vs 9.42 QALYs gained) compared to All UC alone, giving a cost/QALY of $16,761. NI UC & mcfDNA & conditional UC Bronch was also more costly ($162,655 vs $153,642) and more effective (13.19 vs 12.47 LYs gained; 9.96 vs 9.42 evLYs gained; 9.96 vs 9.42 QALYs gained) compared to All UC alone, with a cost/QALY of $16,729. The PSA showed that above a willingness-to-pay threshold of $50,000/QALY, All UC & mcfDNA was the preferred scenario on cost-effectiveness grounds (as it provides the most QALYs gained). Further scenario analyses found that All UC & mcfDNA always improved patient outcomes but was not cost saving, even when the price of mcfDNA was set to $0. CONCLUSIONS: Based on the evidence available at the time of this analysis, this CEA suggests that mcfDNA may be cost-effective when added to All UC, as well as in a scenario using conditional bronchoscopy when NI testing fails to identify a probable infectious etiology for ICHP. Adding mcfDNA testing to UC diagnostic testing should allow more patients to receive appropriate therapy earlier and improve patient outcomes.
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AIM: Insufficient adherence to colorectal cancer (CRC) screening impedes individual and population health benefits, with about one-third of individuals non-adherent to available screening options. The impact of poor adherence is inadequately considered in most health economics models, limiting the evaluation of real-world population-level screening outcomes. This study introduces the CAN-SCREEN (Colorectal cANcer SCReening Economics and adherENce) model, utilizing real-world adherence scenarios to assess the effectiveness of a blood-based test (BBT) compared to existing strategies. MATERIALS AND METHODS: The CAN-SCREEN model evaluates various CRC screening strategies per 1,000 screened individuals for ages 45-75. Adherence is modeled in two ways: (1) full adherence and (2) longitudinally declining adherence. BBT performance is based on recent pivotal trial data while existing strategies are informed using literature. The full adherence model is calibrated using previously published Cancer Intervention and Surveillance Modeling Network (CISNET) models. Outcomes, including life-years gained (LYG), CRC cases averted, CRC deaths averted, and colonoscopies, are compared to no screening. RESULTS: Longitudinal adherence modeling reveals differences in the relative ordering of health outcomes and resource utilization, as measured by the number of colonoscopies performed per 1,000, between screening modalities. BBT outperforms the fecal immunochemical test (FIT) and the multitarget stool DNA (mtsDNA) test with more CRC deaths averted (13) compared to FIT and mtsDNA (7, 11), more CRC cases averted (27 vs. 16, 22) and higher LYG (214 vs. 157, 199). BBT yields fewer CRC deaths averted compared to colonoscopy (13, 15) but requires fewer colonoscopies (1,053 vs. 1,928). LIMITATIONS: Due to limited data, the CAN-SCREEN model with longitudinal adherence leverages evidence-informed assumptions for the natural history and real-world longitudinal adherence to screening. CONCLUSIONS: The CAN-SCREEN model demonstrates that amongst non-invasive CRC screening strategies, those with higher adherence yield more favorable health outcomes as measured by CRC deaths averted, CRC cases averted, and LYG.
This study explored the impact of poor adherence to colorectal cancer (CRC) screening, where about one-third of people face barriers to screening. Common models don't consider real-world adherence, so we introduced the CAN-SCREEN model. It uses real-world data to determine how well a blood-based test (BBT) could work compared to existing tests. We studied people starting CRC screening at age 45. The model looked at two adherence scenarios: assuming everyone follows guidelines, and using real-world data about how people follow screening guidelines over time. The BBT's performance was based on a recent study, and we compared it to existing methods using data from the literature. Results per 1,000 simulated patients showed that the BBT outperforms two guideline-recommended stool-based tests, fecal immunochemical test (FIT) and the multitarget stool DNA (mtsDNA) test, with more CRC deaths averted (13) compared to FIT and mtsDNA (7, 11), more CRC cases averted (27 vs. 16, 22) and higher LYG (214 vs. 157, 199). BBT prevents less CRC deaths than colonoscopy (13 vs. 15), but it leads to fewer colonoscopies (1,053 compared to 1,928). Despite some limitations due to limited data, our model relies on informed assumptions for the natural history of CRC and real-world adherence. In conclusion, our CAN-SCREEN model shows that CRC screening strategies combining good test performance with high adherence give better health outcomes. Adding a blood test, which could be easier for people to use, could save lives and reduce the number of colonoscopies needed.
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Colonoscopia , Neoplasias Colorretais , Detecção Precoce de Câncer , Sangue Oculto , Cooperação do Paciente , Humanos , Neoplasias Colorretais/diagnóstico , Pessoa de Meia-Idade , Idoso , Detecção Precoce de Câncer/métodos , Masculino , Feminino , Análise Custo-BenefícioRESUMO
During cell wall biosynthesis, the Golgi apparatus is the platform for cell wall matrix biosynthesis and the site of packaging, of both matrix polysaccharides and proteins, into secretory vesicles with the correct targeting information. The objective of this study was to dissect the post-Golgi trafficking of cell wall polysaccharides using echidna as a vesicle traffic mutant of Arabidopsis thaliana and the pectin-secreting cells of the seed coat as a model system. ECHIDNA encodes a trans-Golgi network (TGN)-localized protein, which was previously shown to be required for proper structure and function of the secretory pathway. In echidna mutants, some cell wall matrix polysaccharides accumulate inside cells, rather than being secreted to the apoplast. In this study, live cell imaging of fluorescent protein markers as well as transmission electron microscopy (TEM)/immunoTEM of cryofixed seed coat cells were used to examine the consequences of TGN disorganization in echidna mutants under conditions of high polysaccharide production and secretion. While in wild-type seed coat cells, pectin is secreted to the apical surface, in echidna, polysaccharides accumulate in post-Golgi vesicles, the central lytic vacuole and endoplasmic reticulum-derived bodies. In contrast, proteins were partially mistargeted to internal multilamellar membranes in echidna. These results suggest that while secretion of both cell wall polysaccharides and proteins at the TGN requires ECHIDNA, different vesicle trafficking components may mediate downstream events in their secretion from the TGN.
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Arabidopsis/metabolismo , Pectinas/metabolismo , Polissacarídeos/metabolismo , Vesículas Transportadoras/metabolismo , Vacúolos/metabolismo , Rede trans-Golgi/metabolismo , Arabidopsis/genética , Arabidopsis/ultraestrutura , Transporte Biológico , Membrana Celular/metabolismo , Parede Celular/metabolismo , Retículo Endoplasmático/metabolismo , Complexo de Golgi/metabolismo , Mutação , Fenótipo , Mucilagem Vegetal/metabolismo , Sementes/genética , Sementes/metabolismo , Sementes/ultraestruturaRESUMO
Purpose: To estimate the cost-effectiveness of Nefecon in addition to the best supportive care (BSC) vs BSC in a hypothetical cohort of commercially insured adult patients with primary immunoglobulin A nephropathy (IgAN) from a United States (US) societal perspective. Methods: A lifetime horizon, semi-Markov model was developed that consisted of nine health states: chronic kidney disease (CKD) stage 1, 2, 3a, 3b, 4, end-stage renal disease (ESRD) with dialysis, ESRD without dialysis, post-kidney transplant, and death. Health state occupancy was estimated from individual patient-level data from the Phase 3 randomized controlled trial NefIgArd Part A (NCT03643965). Additional scenarios evaluated the impact of varying the time horizon, discounting, costs included, rounds of treatment, and the method used to calculate transition probabilities. Results: In the deterministic base case analysis over a lifetime horizon, Nefecon plus BSC (hereafter Nefecon) had an incremental cost of $3,810 vs BSC. Nefecon resulted in a mean survival gain of 0.247 quality-adjusted life years (QALYs), 0.195 life years (LYs), and 0.244 equal value life years (evLYs) vs BSC alone - this resulted in incremental cost-effectiveness ratios (ICERs) of $15,428 per QALY, $19,502 per LY, and $15,611 per evLY gained. Probabilistic sensitivity analyses estimated that with willingness to pay thresholds of $100,000, $150,000, and $250,000 per QALY gained, Nefecon would be cost-effective over BSC in 66.70%, 75.02%, and 86.82% of cases, respectively. In the scenario analysis, Nefecon remained cost-effective with 4 rounds of treatment. Conclusion: Nefecon was associated with LY and QALY gains vs BSC, with an incremental cost of $3,810. Based on these values, with a willingness to pay threshold of $100,000 per QALY gained, Nefecon was found to be a cost-effective treatment for US adults with primary IgAN.
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Aim: This research evaluated standard Weibull mixture cure (WMC) network meta-analysis (NMA) with Bayesian hierarchical (BH) WMC NMA to inform long-term survival of therapies. Materials & methods: Four trials in previously treated metastatic non-small-cell lung cancer with PD-L1 >1% were used comparing docetaxel with nivolumab, pembrolizumab and atezolizumab. Cure parameters related to a certain treatment class were assumed to share a common distribution. Results: Standard WMC NMA predicted cure rates were 0.03 (0.01; 0.07), 0.18 (0.12; 0.24), 0.07 (0.02; 0.15) and 0.03 (0.00; 0.09) for docetaxel, nivolumab, pembrolizumab and atezolizumab, respectively, with corresponding incremental life years (LY) of 3.11 (1.65; 4.66), 1.06 (0.41; 2.37) and 0.42 (-0.57; 1.68). The Bayesian hierarchical-WMC-NMA rates were 0.06 (0.03; 0.10), 0.17 (0.11; 0.23), 0.12 (0.05; 0.20) and 0.12 (0.03; 0.23), respectively, with incremental LY of 2.35 (1.04; 3.93), 1.67 (0.68; 2.96) and 1.36 (-0.05; 3.64). Conclusion: BH-WMC-NMA impacts incremental mean LYs and cost-effectiveness ratios, potentially affecting reimbursement decisions.