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1.
Nat Genet ; 55(7): 1138-1148, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37308787

RESUMO

Human genetic studies of smoking behavior have been thus far largely limited to common variants. Studying rare coding variants has the potential to identify drug targets. We performed an exome-wide association study of smoking phenotypes in up to 749,459 individuals and discovered a protective association in CHRNB2, encoding the ß2 subunit of the α4ß2 nicotine acetylcholine receptor. Rare predicted loss-of-function and likely deleterious missense variants in CHRNB2 in aggregate were associated with a 35% decreased odds for smoking heavily (odds ratio (OR) = 0.65, confidence interval (CI) = 0.56-0.76, P = 1.9 × 10-8). An independent common variant association in the protective direction ( rs2072659 ; OR = 0.96; CI = 0.94-0.98; P = 5.3 × 10-6) was also evident, suggesting an allelic series. Our findings in humans align with decades-old experimental observations in mice that ß2 loss abolishes nicotine-mediated neuronal responses and attenuates nicotine self-administration. Our genetic discovery will inspire future drug designs targeting CHRNB2 in the brain for the treatment of nicotine addiction.


Assuntos
Nicotina , Tabagismo , Humanos , Animais , Camundongos , Fumar/genética , Tabagismo/genética , Fenótipo , Razão de Chances
2.
Eur J Prev Cardiol ; 30(17): 1874-1880, 2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-37314419

RESUMO

AIMS: Despite intensive lipid-lowering therapies (LLTs), most patients with homozygous familial hypercholesterolaemia (HoFH) do not achieve guideline recommended low-density lipoprotein cholesterol (LDL-C) targets and are at increased risk of premature cardiovascular death. This analysis aimed to predict the impact of evinacumab and standard-of-care LLTs on life expectancy in an HoFH population using mathematical modelling. METHODS AND RESULTS: Mathematical models were developed using efficacy data for evinacumab from the phase 3 ELIPSE HoFH trial plus efficacy data for standard-of-care LLTs from peer-reviewed publications. Treatment strategies evaluated included (i) untreated, (ii) high-intensity statin (HIS) only, (iii) HIS plus ezetimibe, (iv) HIS plus ezetimibe plus proprotein convertase subtilisin/kexin type 9 inhibitor (PCSK9i), and (v) HIS plus ezetimibe plus PCSK9i plus evinacumab. Markov analyses were used to assess differences in survival probability for different LLT strategies. The median survival for untreated HoFH patients was only 33-43 years, depending on different assumptions on baseline untreated LDL-C levels. In the most robust model, we estimated that HIS increased median survival by 9 years and ezetimibe further increased median survival by an additional 9 years. When PCSK9i was added on top of HIS plus ezetimibe, median survival was further improved by 14 years. Finally, the addition of evinacumab to standard-of-care LLTs was estimated to increase median survival by ∼12 years. CONCLUSION: In this mathematical modelling analysis, evinacumab treatment could potentially increase long-term survival vs. standard-of-care LLTs for patients with HoFH.


This mathematical modelling analysis demonstrated that evinacumab in addition to standard-of-care lipid-lowering treatments (LLTs; high-intensity statin plus ezetimibe plus proprotein convertase subtilisin/kexin type 9 inhibitor) could increase long-term survival to a median of 77 years vs. the 65 years achieved with only standard-of-care LLTs in patients with homozygous familial hypercholesterolaemia.


Assuntos
Anticolesterolemiantes , Hipercolesterolemia Familiar Homozigota , Inibidores de Hidroximetilglutaril-CoA Redutases , Hiperlipoproteinemia Tipo II , Humanos , LDL-Colesterol , Anticolesterolemiantes/efeitos adversos , Hiperlipoproteinemia Tipo II/diagnóstico , Hiperlipoproteinemia Tipo II/tratamento farmacológico , Padrão de Cuidado , Ezetimiba/uso terapêutico
3.
J Mol Diagn ; 24(8): 901-914, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35688357

RESUMO

The study evaluated the diagnostic value and cost-effectiveness of next-generation sequencing (NGS)-based testing versus various combinations of single-gene tests (SGTs) for selection of first-line treatment for patients with advanced/metastatic non-squamous non-small-cell lung cancer in the United States. A dynamic decision analysis model was developed comparing NGS versus SGT from a payer perspective. Inputs were obtained from published sources and included diagnostic performance, biomarker-positive disease rates, biomarker-directed recommendations for treatment, and survival outcomes. Costs were reported in 2020 US dollars. In the base case, NGS improved the detection of actionable biomarkers by 74.4%, increased the proportion of patients receiving biomarker-driven therapy by 11.9%, and decreased the proportion of patients with biomarker-positive disease receiving non-biomarker-driven first-line treatment by 40.5%. The incremental cost-effectiveness ratio per life-year gained of NGS testing versus SGT was $7224 (excluding post-diagnostic costs); the incremental cost-effectiveness ratio for NGS-directed therapy was $148,786 versus SGT-directed therapy. Sensitivity analyses confirmed the robustness of these findings; survival outcomes and targeted therapy costs had the greatest impact on results. Testing strategies with NGS are more comprehensive in the detection of actionable biomarkers and can improve the proportion of patients receiving biomarker-driven therapies. NGS testing may provide a cost-effective strategy for advanced/metastatic non-squamous non-small-cell lung cancer; however, the value of NGS-directed therapy varies by the willingness-to-pay threshold of the decision-maker.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Análise Custo-Benefício , Testes Genéticos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Estados Unidos
4.
J Med Econ ; 24(1): 279-290, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33502905

RESUMO

OBJECTIVES: Tofacitinib is an oral, small molecule Janus kinase (JAK) inhibitor for the treatment of ulcerative colitis (UC). This study assessed the cost-effectiveness of tofacitinib versus other available treatments for patients with moderate to severe UC following an inadequate response to conventional treatment and who are either naïve to or have failed previous biologics in Germany. METHODS: A Markov cohort model was developed to evaluate the differences in long-term costs and outcomes between tofacitinib and its comparators from the perspective of German statutory health insurance (SHI) for patients either naïve or exposed to biologics. Tofacitinib was compared to infliximab, infliximab biosimilar, adalimumab, adalimumab biosimilar, golimumab, vedolizumab, ustekinumab, and conventional therapy. Health states modeled were remission, treatment response, active UC, and post-colectomy. Patients not responding to treatment could switch to a different treatment. Treatment efficacy for induction and maintenance phases were assessed by a systematic literature review (SLR) and network meta-analysis (NMA). The model included costs associated with drug administration, adverse events, and medical resource use. Extensive deterministic and probabilistic sensitivity analyses (DSA and PSA) were conducted. RESULTS: Over a life-time horizon, patients treated with tofacitinib gained 0.035-0.083 quality-adjusted life-years (QALYs) and had direct cost savings to the SHI of €4,228-€17,184 compared to biologic treatments other than adalimumab biosimilar. When compared to adalimumab biosimilar, treatment with tofacitinib resulted in an incremental cost-effectiveness ratio (ICER) of €17,497 per QALY gained and can be considered a cost-effective alternative. Compared with conventional therapy, tofacitinib resulted in a lower ICER than all other biologics. The DSA showed that the model results were most influenced by differences in treatment efficacy. The PSA suggested confidence in the base-case results considering uncertainty around parameters. CONCLUSIONS: The results of this economic model suggest tofacitinib is a cost-effective treatment option for patients with moderate to severe UC in Germany.


Assuntos
Colite Ulcerativa , Ustekinumab , Adalimumab , Anticorpos Monoclonais , Anticorpos Monoclonais Humanizados , Colite Ulcerativa/tratamento farmacológico , Análise Custo-Benefício , Humanos , Infliximab , Piperidinas , Pirimidinas , Anos de Vida Ajustados por Qualidade de Vida , Ustekinumab/uso terapêutico
5.
J Med Econ ; 22(9): 859-868, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31012362

RESUMO

Aims: To evaluate the cost differences between a treatment strategy including tofacitinib (TOFA) vs treatment strategies including adalimumab (ADA), golimumab (GOL), infliximab (IFX), and vedolizumab (VEDO) among all patients with moderate-to-severe ulcerative colitis (UC) (further stratified by patients naïve/exposed to tumor necrosis factor inhibitors [TNFis]). Materials and methods: An Excel-based decision-analytic model was developed to evaluate costs from the perspective of a third-party US payer over 2 years. Efficacy and safety parameters were taken from prescribing information and published trials. All patients started induction therapy on the first treatment in the strategy and continued if efficacy criteria were met and no major adverse event occurred (in which cases they proceeded to the next treatment in the strategy). Results: The cost per member per month (PMPM) of the TOFA->IFX->VEDO->GOL strategy ($1.11) was lower than that of the ADA->IFX->VEDO->GOL strategy ($1.34; Δ = $-0.23) among the TNFi-naïve population (n = 204 patients out of a plan of one million members). Similarly, the use of TOFA before ADA (i.e. TOFA->ADA->IFX-> VEDO) was also associated with lower PMPM costs than the use of ADA before TOFA (i.e. ADA->TOFA->IFX->VEDO): $1.15 vs $1.25 (Δ = $-0.10). Similar, and often larger, differences were observed in both the overall moderate-to-severe population and the TNFi-exposed population. Sensitivity analyses resulted in the same conclusions. Limitations: Our model relied on efficacy data from prescribing information and published trials, which were not head-to-head and slightly differed with respect to methods. Additionally, our model used representative minor and major ADRs (and the associated costs) to represent toxicity management, which was a simplifying assumption. Conclusions: This analysis, the first of its kind to evaluate TOFA vis-à-vis other advanced therapies in the US, suggests the early use of TOFA among both TNFi-naïve and TNFi-failure patients results in lower PMPM costs compared with other treatment alternatives.


Assuntos
Colite Ulcerativa/tratamento farmacológico , Fármacos Gastrointestinais/economia , Fármacos Gastrointestinais/uso terapêutico , Gastos em Saúde/estatística & dados numéricos , Piperidinas/economia , Piperidinas/uso terapêutico , Pirimidinas/economia , Pirimidinas/uso terapêutico , Pirróis/economia , Pirróis/uso terapêutico , Adalimumab/economia , Adalimumab/uso terapêutico , Anticorpos Monoclonais/economia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/economia , Anticorpos Monoclonais Humanizados/uso terapêutico , Análise Custo-Benefício , Fármacos Gastrointestinais/efeitos adversos , Recursos em Saúde/economia , Recursos em Saúde/estatística & dados numéricos , Serviços de Saúde/economia , Serviços de Saúde/estatística & dados numéricos , Humanos , Infliximab/economia , Infliximab/uso terapêutico , Modelos Econométricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Piperidinas/efeitos adversos , Pirimidinas/efeitos adversos , Pirróis/efeitos adversos , Índice de Gravidade de Doença , Fator de Necrose Tumoral alfa/agonistas , Estados Unidos
6.
Pharmacoecon Open ; 3(3): 321-331, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30617952

RESUMO

OBJECTIVE: Our objective was to evaluate the cost effectiveness of the combination of nivolumab and ipilimumab, referred to as "Regimen", as a first-line treatment for patients with advanced melanoma from the perspective of Canada's public healthcare system. METHODS: We developed a partitioned-survival model (progression-free survival, post-progression survival, and death) to determine the clinical and economic outcomes of immunotherapy for advanced melanoma over a 20-year time horizon. Regimen was compared with nivolumab, ipilimumab, and pembrolizumab. Two treatment durations for pembrolizumab were considered: (1) maximum of 24 months or until progression or (2) no maximum duration, until progression. The model used data from CheckMate-067 (28 months' follow-up) for treatments involving nivolumab and ipilimumab. The efficacy of pembrolizumab was estimated using indirect comparisons. A scenario looking at the cost of subsequent treatments following disease progression was examined. RESULTS: Regimen had better outcomes and was cost effective compared with all other immunotherapies at a threshold of $CAN100,000 per quality-adjusted life-year (QALY) gained. Compared with nivolumab and ipilimumab, the incremental cost-effectiveness ratios (ICERs) were $CAN47,119 and 66,750 per QALY, respectively. Compared with pembrolizumab with a treatment duration cap, the ICER was $CAN85,436. When assuming no duration cap, Regimen dominated pembrolizumab. With the inclusion of subsequent treatment costs following progression, Regimen's ICER improved compared with all other comparators. CONCLUSIONS: Despite the advent of effective new therapies for advanced melanoma, prognosis remains poor for some patients. Compared with other immunotherapies, Regimen offers marked benefit and may be a cost-effective treatment option.

7.
BMC Health Serv Res ; 17(1): 74, 2017 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-28114939

RESUMO

BACKGROUND: Prior analyses beyond clinical trials are yet to evaluate the projected lifetime benefit of apixaban treatment compared to low-molecular-weight heparin (LMWH)/vitamin K antagonist (VKA) for treatment of venous thromboembolism (VTE) and prevention of recurrences. The objective of this study is to assess the cost-effectiveness of initial plus extended treatment with apixaban versus LMWH/VKA for either initial treatment only or initial plus extended treatment. METHODS: A Markov cohort model was developed to evaluate the lifetime clinical and economic impact of treatment of VTE and prevention of recurrences with apixaban (starting at 10 mg BID for 1 week, then 5 mg BID for 6 months, then 2.5 mg BID for an additional 12 months) versus LMWH/VKA for 6 months and either no further treatment or extended treatment with VKA for an additional 12 months. Clinical event rates to inform the model were taken from the AMPLIFY and AMPLIFY-EXT trials and a network meta-analysis. Background mortality rates, costs, and utilities were obtained from published sources. The analysis was conducted from the perspective of the United Kingdom National Health Service. The evaluated outcomes included the number of events avoided in a 1000-patient cohort, total costs, life-years, quality-adjusted life-years (QALYs), and cost per QALY gained. RESULTS: Initial plus extended treatment with apixaban was superior to both treatment durations of LMWH/VKA in reducing the number of bleeding events, and was superior to initial LMWH/VKA for 6 months followed by no therapy, in reducing VTE recurrences. Apixaban treatment was cost-effective compared to 6-month treatment with LMWH/VKA at an incremental cost-effectiveness ratio (ICER) of £6692 per QALY. When initial LMWH/VKA was followed by further VKA therapy for an additional 12 months (i.e., total treatment duration of 18 months), apixaban was cost-effective at an ICER of £8528 per QALY gained. Sensitivity analysis suggested these findings were robust over a wide range of inputs and scenarios for the model. CONCLUSIONS: In the UK, initial plus extended treatment with apixaban for treatment of VTE and prevention of recurrences appears to be economical and a clinically effective alternative to LMWH/VKA, whether used for initial or initial plus extended treatment.


Assuntos
Anticoagulantes/economia , Heparina de Baixo Peso Molecular/economia , Heparina de Baixo Peso Molecular/uso terapêutico , Pirazóis/economia , Pirazóis/uso terapêutico , Piridonas/economia , Piridonas/uso terapêutico , Tromboembolia Venosa/tratamento farmacológico , Tromboembolia Venosa/prevenção & controle , Vitamina K/antagonistas & inibidores , Anticoagulantes/uso terapêutico , Análise Custo-Benefício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anos de Vida Ajustados por Qualidade de Vida , Recidiva , Prevenção Secundária , Medicina Estatal/economia , Resultado do Tratamento , Reino Unido , Tromboembolia Venosa/economia
8.
Clin Ther ; 38(3): 478-93.e1-16, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26922297

RESUMO

PURPOSE: To assess the cost-effectiveness of apixaban versus rivaroxaban, low-molecular-weight heparin (LMWH)/dabigatran, and LMWH/vitamin K antagonist (VKA) for the initial treatment and prevention of recurrent thromboembolic events in patients with venous thromboembolism (VTE). METHODS: A Markov model was developed to evaluate the pharmacoeconomic effect of 6 months of treatment with apixaban versus other anticoagulants over a lifetime horizon. Network meta-analyses were conducted using the results of the Apixaban after the Initial Management of Pulmonary Embolism and Deep Vein Thrombosis with First-Line Therapy (AMPLIFY), EINSTEIN-pooled, and RE-COVER I and II trials for the following end points: recurrent VTE, major bleeds, clinically relevant non-major bleeds, and treatment discontinuations. The analysis was conducted from the perspective of the United Kingdom National Health Service. The outcomes evaluated were the number of events avoided in a 1000-patient cohort, total costs, life years, quality-adjusted life years (QALYs), and cost per QALY gained over a patient's lifetime. FINDINGS: Treatment for 6 months with apixaban was projected to result in fewer recurrent VTE and bleeding events in comparison to rivaroxaban, LMWH/dabigatran, and LMWH/VKA. Apixaban was cost-effective compared with LMWH/VKA at an incremental cost-effectiveness ratio of £2520 per QALY gained and was a dominant (ie, lower costs and higher QALYs) alternative to either rivaroxaban or LMWH/dabigatran. Sensitivity analysis indicated that results were robust over a wide range of inputs. IMPLICATIONS: The assessment of the effects and costs of apixaban in this study predicted that apixaban is a dominant alternative to rivaroxaban and LMWH/dabigatran and a cost-effective alternative to LMWH/VKA for 6 months of treatment of VTE and the prevention of recurrence.


Assuntos
Anticoagulantes/economia , Dabigatrana/economia , Heparina de Baixo Peso Molecular/economia , Pirazóis/economia , Piridonas/economia , Rivaroxabana/economia , Tromboembolia Venosa/tratamento farmacológico , Anticoagulantes/uso terapêutico , Análise Custo-Benefício , Dabigatrana/uso terapêutico , Feminino , Hemorragia/induzido quimicamente , Heparina de Baixo Peso Molecular/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , Pirazóis/uso terapêutico , Piridonas/uso terapêutico , Anos de Vida Ajustados por Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Recidiva , Rivaroxabana/uso terapêutico , Prevenção Secundária/economia , Reino Unido , Tromboembolia Venosa/prevenção & controle
9.
J Med Econ ; 19(6): 557-67, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26761644

RESUMO

Background and objective Venous thromboembolism (VTE) is associated with long-term clinical and economic burden. Clinical guidelines generally recommend at least 3 months of anticoagulation, but, in clinical practice, concerns over bleeding risk often limit extended treatment. Apixaban was studied for extended VTE treatment in the AMPLIFY-EXT trial, demonstrating superiority to placebo in VTE reduction without increasing risk of major bleeding. This study assessed the long-term clinical and economic benefits of extending treatment with apixaban when clinical equipoise exists compared to standard of care with enoxaparin/warfarin and other novel oral anti-coagulants (NOACs) for the treatment and prevention of recurrent VTE in Canada. Methods A Markov model was developed to follow patients with VTE over their lifetimes. Efficacy and safety for apixaban and enoxaparin/warfarin were based on AMPLIFY and AMPLIFY-EXT, while relative efficacy to other NOACs was synthesized by network meta-analysis (NMA). Dosages for NOACs and enoxaparin/warfarin were based on their respective trials and were given up to 18 months and up to 6 months, followed by no treatment, respectively. Patient quality adjusted life years (QALYs) were based on published studies, and costs for resource utilization were from a Ministry of Health perspective, expressed as 2014 CAD ($). Results Extended treatment with apixaban compared to enoxaparin/warfarin resulted in fewer recurrent VTEs, VTE-related deaths, and bleeding events, but at slightly increased cost. The incremental cost-effectiveness ratio was $4828 per QALY gained. Compared to other NOACs, apixaban had the fewest bleeding events, similar recurrent VTE events, and the lowest overall cost, which was driven by the strong bleeding profile. In scenario analyses of acute and lifetime treatments, apixaban was cost-effective against all strategies. Conclusions Extended treatment with apixaban can offer substantial clinical benefits and is a cost-effective alternative to enoxaparin/warfarin and other NOACs.


Assuntos
Anticoagulantes/economia , Pirazóis/economia , Piridonas/economia , Tromboembolia Venosa/tratamento farmacológico , Tromboembolia Venosa/prevenção & controle , Anticoagulantes/uso terapêutico , Canadá , Análise Custo-Benefício , Enoxaparina/economia , Enoxaparina/uso terapêutico , Feminino , Hemorragia/induzido quimicamente , Humanos , Coeficiente Internacional Normatizado , Masculino , Cadeias de Markov , Pessoa de Meia-Idade , Pirazóis/uso terapêutico , Piridonas/uso terapêutico , Anos de Vida Ajustados por Qualidade de Vida , Varfarina/economia , Varfarina/uso terapêutico
10.
P T ; 38(2): 109-15, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23599678

RESUMO

OBJECTIVE: We assessed the potential clinical and economic impact of coronary heart disease (CHD) and diabetes arising after the use of second-generation ("atypical") antipsychotic agents for the treatment of chronic schizophrenia. We compared the use of these medications in patients with a higher risk of cardiometabolic adverse events (in a higher-risk scenario) and in patients with a lower risk (in a lower-risk scenario). Our U.S.-based analysis estimated the costs of CHD and diabetes arising from antipsychotic medication-related cardiometabolic effects. METHODS: We constructed a health economic model to predict the 5-year incidence of CHD and diabetes and associated costs after treatment. In this cost-consequence model, we used CHD risk functions derived from the Framingham Heart Study and diabetes risk functions derived from the Atherosclerosis Risk in Communities (ARIC) study. Patient characteristics and treatment effects on cardiometabolic risk factors were estimated from the Clinical Trials of Antipsychotic Treatment Effectiveness (CATIE) study. We evaluated two cost-consequence scenarios: the incidence of CHD and diabetes predicted for 1,000 patients with chronic schizophrenia in a higher-risk scenario based on data from CATIE associated with olanzapine (Zyprexa) and in a lower-risk scenario with ziprasidone (Geodon). We evaluated rates of adverse outcomes for each scenario and the cost of treatment for CHD and diabetes. All costs were reported in 2011 U.S. dollars. Because Medicaid is often the payer for patients with chronic schizophrenia, all costs in this analysis were derived from the perspective of Medicaid. RESULTS: Over a period of 5 years in 1,000 patients with chronic schizophrenia, the higher-risk scenario with olanzapine showed a 9% increased incidence of CHD and a 59% increased incidence of diabetes, compared with no change in treatment from baseline. By contrast, the lower-risk scenario with ziprasidone showed a 9% reduced incidence of CHD and a 10% reduced incidence of diabetes. The higher-risk scenario led to increased CHD-related costs of $83,206 and to increased diabetes-related costs of $456,399. CONCLUSION: Our study underscores the importance of monitoring the established risk factors for CHD and diabetes in patients using second-generation antipsychotic drugs. Lower-risk agents from this class may lead to substantially decreased costs in the management of CHD and diabetes when compared with higher-risk agents.

11.
G3 (Bethesda) ; 1(4): 247-58, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22384336

RESUMO

Though highly efficient at fermenting hexose sugars, Saccharomyces cerevisiae has limited ability to ferment five-carbon sugars. As a significant portion of sugars found in cellulosic biomass is the five-carbon sugar xylose, S. cerevisiae must be engineered to metabolize pentose sugars, commonly by the addition of exogenous genes from xylose fermenting fungi. However, these recombinant strains grow poorly on xylose and require further improvement through rational engineering or evolutionary adaptation. To identify unknown genes that contribute to improved xylose fermentation in these recombinant S. cerevisiae, we performed genome-wide synthetic interaction screens to identify deletion mutants that impact xylose utilization of strains expressing the xylose isomerase gene XYLA from Piromyces sp. E2 alone or with an additional copy of the endogenous xylulokinase gene XKS1. We also screened the deletion mutant array to identify mutants whose growth is affected by xylose. Our genetic network reveals that more than 80 nonessential genes from a diverse range of cellular processes impact xylose utilization. Surprisingly, we identified four genes, ALP1, ISC1, RPL20B, and BUD21, that when individually deleted improved xylose utilization of both S. cerevisiae S288C and CEN.PK strains. We further characterized BUD21 deletion mutant cells in batch fermentations and found that they produce ethanol even the absence of exogenous XYLA. We have demonstrated that the ability of laboratory strains of S. cerevisiae to utilize xylose as a sole carbon source is suppressed, which implies that S. cerevisiae may not require the addition of exogenous genes for efficient xylose fermentation.

12.
Pharmacoeconomics ; 28(9): 751-64, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20623994

RESUMO

BACKGROUND: Bipolar I disorder (BPD I) is a recurrent illness that affects 1% of the US population and constitutes a large economic burden. However, few studies have investigated the cost effectiveness of maintenance treatment options for BPD I. OBJECTIVE: To determine the cost effectiveness of maintenance treatment with quetiapine fumarate extended-release (XR) tablets in combination with mood stabilizers (lithium or divalproex) in comparison with the following treatments: placebo in combination with lithium or divalproex; no maintenance treatment; lithium monotherapy; lamotrigine monotherapy; olanzapine monotherapy; and aripiprazole monotherapy. METHODS: The analysis was conducted from the societal and payer perspectives in the US, using a Markov model. The model simulated a cohort of 1000 stabilized BPD I patients and estimated the quarterly risk in three health states: euthymia, mania and depression. Efficacy data were derived from two randomized, double-blind trials comparing quetiapine + lithium/divalproex with placebo + lithium/divalproex for up to 2 years, as well as other published literature. Resource data were extracted from published literature. Drug costs, hospitalizations and physician visits were among the direct costs. Indirect costs included absenteeism, and mortality rates included suicide. Benefits and costs were discounted at 3% and the price reference year was 2009. Endpoints included number of acute mood episodes, hospitalizations due to an acute mood event and costs per QALY. Probabilistic sensitivity analysis (PSA) was conducted to evaluate uncertainty in the model inputs. RESULTS: Treatment with quetiapine XR + lithium/divalproex was associated with reductions in acute mania (46%), acute depression (41%) and related hospitalizations (44%) compared with placebo + lithium/divalproex, and similar reductions in events were observed relative to lithium monotherapy. In the base-case analysis from the payer perspective, the discounted incremental cost per QALY for quetiapine XR + lithium/divalproex compared with placebo + lithium/divalproex was $US22 959, and compared with lithium monotherapy was $US100 235, while all other comparators were dominated. PSA showed these results to be robust to select assumptions. CONCLUSIONS: Quetiapine XR + lithium/divalproex may be a cost-effective maintenance treatment option for patients with BPD I.


Assuntos
Antimaníacos/economia , Antimaníacos/uso terapêutico , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/economia , Dibenzotiazepinas/economia , Dibenzotiazepinas/uso terapêutico , Modelos Econômicos , Absenteísmo , Antimaníacos/administração & dosagem , Antipsicóticos/administração & dosagem , Antipsicóticos/economia , Antipsicóticos/uso terapêutico , Aripiprazol , Benzodiazepinas/administração & dosagem , Benzodiazepinas/economia , Benzodiazepinas/uso terapêutico , Transtorno Bipolar/mortalidade , Análise Custo-Benefício , Preparações de Ação Retardada/economia , Dibenzotiazepinas/administração & dosagem , Quimioterapia Combinada/economia , Honorários Farmacêuticos , Custos de Cuidados de Saúde , Preços Hospitalares , Humanos , Lamotrigina , Compostos de Lítio/administração & dosagem , Compostos de Lítio/economia , Compostos de Lítio/uso terapêutico , Cadeias de Markov , Olanzapina , Piperazinas/administração & dosagem , Piperazinas/economia , Piperazinas/uso terapêutico , Anos de Vida Ajustados por Qualidade de Vida , Fumarato de Quetiapina , Quinolonas/administração & dosagem , Quinolonas/economia , Quinolonas/uso terapêutico , Risco , Comprimidos , Triazinas/administração & dosagem , Triazinas/economia , Triazinas/uso terapêutico , Estados Unidos , Ácido Valproico/administração & dosagem , Ácido Valproico/economia , Ácido Valproico/uso terapêutico
13.
J Med Econ ; 12(4): 259-68, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19769548

RESUMO

BACKGROUND: Bipolar I disorder is a recurrent illness that affects 1% of the US population and constitutes a large economic burden. Few studies have investigated the cost-effectiveness of maintenance treatment options. The objective of this analysis was to assess the cost-effectiveness of quetiapine (QTP) in combination with lithium (Li) or divalproex (DVP) compared with that of Li or DVP alone for maintenance treatment of bipolar disorder. METHODS: The cost-effectiveness of maintenance treatment with QTP in combination with Li or DVP was compared with placebo (PBO) in combination with Li or DVP from a US direct costs perspective using a Markov model. The model simulated a cohort of 1,000 stabilized patients with bipolar I disorder and estimated the quarterly risk in three health states: euthymia, mania, and depression. Efficacy data were derived from two randomized, double-blind, placebo-controlled trials comparing QTP + Li/DVP with PBO + Li/DVP for up to 2 years. Resource data were obtained from published literature. Direct costs included drug costs, hospitalizations, and physician visits. Outcomes and costs were discounted at 3% and the price reference year was 2007. Endpoints included the number of acute mood episodes, hospitalizations due to an acute mood event, and costs per quality-adjusted life-years. A probabilistic sensitivity analysis (PSA) was conducted to evaluate uncertainty. RESULTS: In the base-case analysis, QTP + Li/DVP dominated PBO + Li/DVP. The PSA showed these results to be robust. In addition, treatment with QTP + Li/DVP was associated with reductions in acute manic episodes (46%), acute depressive episodes (41%), and related hospitalizations (44%) compared with PBO + Li/DVP. CONCLUSIONS: These analyses, based on two randomized clinical trials, suggest that QTP + Li/DVP is a cost-effective maintenance treatment option for patients with bipolar I disorder compared with Li or DVP alone.


Assuntos
Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/economia , Dibenzotiazepinas/economia , Compostos de Lítio/economia , Ácido Valproico/economia , Adolescente , Adulto , Idoso , Anticonvulsivantes/economia , Anticonvulsivantes/uso terapêutico , Antipsicóticos/economia , Antipsicóticos/uso terapêutico , Análise Custo-Benefício , Dibenzotiazepinas/uso terapêutico , Quimioterapia Combinada/economia , Feminino , Humanos , Compostos de Lítio/uso terapêutico , Masculino , Cadeias de Markov , Pessoa de Meia-Idade , Fumarato de Quetiapina , Índice de Gravidade de Doença , Ácido Valproico/uso terapêutico , Adulto Jovem
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