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2.
Lancet Planet Health ; 8(9): e647-e656, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39243780

RESUMO

BACKGROUND: Health co-benefits are a key potential advantage of transport decarbonisation policy. However, health effects will occur in the context of existing transport-health inequities and decarbonisation policies will themselves affect inequities. This research examines the effects of national decarbonisation pathways for transport on population health, health inequity, and health-system costs in Aotearoa New Zealand. METHODS: We modelled the health, health-system, and environmental impacts of two pathways to net zero for transport developed by the New Zealand Climate Change Commission using a proportional multistate lifetable model. The behaviour pathway emphasises a mixed approach, including reduced driving, increased cycling and use of public transport, and light vehicle electrification, and the technology pathway focuses on vehicle electrification. We used data from transport, environmental, population health, and health-care sources to populate the model. We simulated changes in health effects through the pathways of physical activity, air pollution (PM2·5 and NO2), and injury for the Aotearoa New Zealand population from 2018 to 2050. We modelled impacts for Maori (the Indigenous People of Aotearoa) and non-Maori. For each pathway to net zero, we calculated changes in overall health-adjusted life-years (HALYs), age-standardised HALYs, and rate ratios for Maori and non-Maori. We also calculated changes in health-system costs and transport greenhouse gas emissions. 95% uncertainty intervals (95% UIs) were derived for all model outputs by use of a Monte Carlo simulation. FINDINGS: Both pathways show improvements in population health, reductions in health-system costs, and reduced lifecycle greenhouse gas emissions compared with baseline, although health gains were substantially larger in the behaviour pathway. For example, an extra 2100 HALYs (95% UI 1500-3100) were gained in the behaviour scenario compared with baseline. Health gains were 20-30% larger for Maori than non-Maori in both pathways, although more HALYs were gained by Maori in the behaviour pathway. For the cohort aged 0-4 years in 2018, healthy life expectancy differences between Maori and non-Maori reduced by 0·5% in the behaviour pathway over their lifetime. HALYs gained by Maori and non-Maori were altered substantially depending on assumptions about the equity of the implemented pathway. INTERPRETATION: Decarbonising transport might improve overall population health, save the health system money, and reduce health inequities between Maori and non-Maori. Pathways that increase physical activity have a larger effect on population health than those that rely on low-emission vehicles. The effects on inequity between Maori and non-Maori are larger in the behaviour pathway than in the technology pathway but dependent on how equitably policies supporting decarbonisation are implemented. FUNDING: Health Research Council of New Zealand and University of Otago.


Assuntos
Saúde da População , Humanos , Poluição do Ar , Mudança Climática , Modelos Teóricos , Nova Zelândia , Meios de Transporte/estatística & dados numéricos , Povo Maori
3.
Materials (Basel) ; 17(13)2024 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-38998384

RESUMO

This paper forms part of an ongoing investigation into the tools required in linear elastic fracture mechanics (LEFM) for evaluating the durability of components designed for limited life replacement. In this study, we demonstrate that the USAF 'Characteristic K' method, when combined with the Hartman-Schijve adaptation of the NASGRO crack growth formula, can predict the impact of underloads on the propagation of small cracks in aluminum alloy AA7050-T7451 with reasonable accuracy. The published da/dN versus ΔK small crack growth curves associated with five specific underload spectra are examined. It is found that, in each case, there is reasonably good agreement between the predicted and the measured curves. To the best of the author's knowledge, this paper is the first to highlight the ability of the USAF Characteristic K approach, when coupled with the Hartman-Schijve equation, to reasonably accurately predict the growth of small cracks subjected to a range of underload spectra.

4.
Materials (Basel) ; 17(11)2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38893923

RESUMO

This paper presents the results of an extensive investigation into the durability of cold spray repairs to corrosion damage in AA7075-T7351 aluminium alloy specimens where, prior to powder deposition, the surface preparation involved grit blasting. In this context, it is shown that the growth of small naturally occurring cracks in cold spray repairs to simulated corrosion damage can be accurately computed using the Hartman-Schijve crack growth equation in a fashion that is consistent with the requirements delineated in USAF Structures Bulletin EZ-SB-19-01, MIL-STD-1530D, and the US Joint Services Structural Guidelines JSSG2006. The relatively large variation in the da/dN versus ΔK curves associated with low values of da/dN highlights the fact that, before any durability assessment of a cold spray repair to an operational airframe is attempted, it is first necessary to perform a sufficient number of tests so that the worst-case small crack growth curve needed to perform the mandated airworthiness certification analysis can be determined.

6.
Polymers (Basel) ; 16(9)2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38732768

RESUMO

Prior studies into fatigue crack growth (FCG) in fibre-reinforced polymer composites have shown that the two methodologies of Simple-Scaling and the Hartman-Schijve crack growth equation, which is based on relating the FCG rate to the Schwalbe crack driving force, Δκ, were able to account for differences observed in the measured delamination growth curves. The present paper reveals that these two approaches are also able to account for differences seen in plots of the rate of crack growth, da/dt, versus the range of the imposed stress intensity factor, ΔK, associated with fatigue tests on different grades of high-density polyethylene (HDPE) polymers, before and after electron-beam irradiation, and for tests conducted at different R ratios. Also, these studies are successfully extended to consider FCG in an acrylonitrile butadiene styrene (ABS) polymer that is processed using both conventional injection moulding and additive-manufactured (AM) 3D printing.

7.
CPT Pharmacometrics Syst Pharmacol ; 13(6): 994-1005, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38532525

RESUMO

Trastuzumab deruxtecan (T-DXd; DS-8201; ENHERTU®) is a human epithelial growth factor receptor 2 (HER2)-directed antibody drug conjugate (ADC) with demonstrated antitumor activity against a range of tumor types. Aiming to understand the relationship between antigen expression and downstream efficacy outcomes, T-DXd was administered in tumor-bearing mice carrying NCI-N87, Capan-1, JIMT-1, and MDA-MB-468 xenografts, characterized by varying HER2 levels. Plasma pharmacokinetics (PK) of total antibody, T-DXd, and released DXd and tumor concentrations of released DXd were evaluated, in addition to monitoring γΗ2AX and pRAD50 pharmacodynamic (PD) response. A positive relationship was observed between released DXd concentrations in tumor and HER2 expression, with NCI-N87 xenografts characterized by the highest exposures compared to the remaining cell lines. γΗ2AX and pRAD50 demonstrated a sustained increase over several days occurring with a time delay relative to tumoral-released DXd concentrations. In vitro investigations of cell-based DXd disposition facilitated the characterization of DXd kinetics across tumor cells. These outputs were incorporated into a mechanistic mathematical model, utilized to describe PK/PD trends. The model captured plasma PK across dosing arms as well as tumor PK in NCI-N87, Capan-1, and MDA-MB-468 models; tumor concentrations in JIMT-1 xenografts required additional parameter adjustments reflective of complex receptor dynamics. γΗ2AX longitudinal trends were well characterized via a unified PD model implemented across xenografts demonstrating the robustness of measured PD trends. This work supports the application of a mechanistic model as a quantitative tool, reliably projecting tumor payload concentrations upon T-DXd administration, as the first step towards preclinical-to-clinical translation.


Assuntos
Imunoconjugados , Receptor ErbB-2 , Trastuzumab , Ensaios Antitumorais Modelo de Xenoenxerto , Animais , Trastuzumab/farmacocinética , Trastuzumab/farmacologia , Receptor ErbB-2/metabolismo , Camundongos , Humanos , Imunoconjugados/farmacocinética , Imunoconjugados/farmacologia , Linhagem Celular Tumoral , Feminino , Camptotecina/análogos & derivados , Camptotecina/farmacocinética , Camptotecina/farmacologia , Antineoplásicos Imunológicos/farmacocinética , Antineoplásicos Imunológicos/farmacologia , Antineoplásicos Imunológicos/administração & dosagem , Camundongos Nus
8.
Environ Monit Assess ; 196(4): 379, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499718

RESUMO

Airborne metals and organic pollutants are linked to severe human health impacts, i.e. affecting the nervous system and being associated with cancer. Airborne metals and polycyclic aromatic hydrocarbons (PAHs) in urban environments are derived from diverse sources, including combustion and industrial and vehicular emissions, posing a threat to air quality and subsequently human health. A lichen biomonitoring approach was used to assess spatial variability of airborne metals and PAHs, identify potential pollution sources and assess human health risks across the City of Manchester (UK). Metal concentrations recorded in lichen samples were highest within the city centre area and along the major road network, and lichen PAH profiles were dominated by 4-ring PAHs (189.82 ng g-1 in Xanthoria parietina), with 5- and 6-ring PAHs also contributing to the overall PAH profile. Cluster analysis and pollution index factor (PIF) calculations for lichen-derived metal concentrations suggested deteriorated air quality being primarily linked to vehicular emissions. Comparably, PAH diagnostic ratios identified vehicular sources as a primary cause of PAH pollution across Manchester. However, local more complex sources (e.g. industrial emissions) were further identified. Human health risk assessment found a "moderate" risk for adults and children by airborne potential harmful element (PHEs) concentrations, whereas PAH exposure in Manchester is potentially linked to 1455 (ILCR = 1.45 × 10-3) cancer cases (in 1,000,000). Findings of this study indicate that an easy-to-use lichen biomonitoring approach can aid to identify hotspots of impaired air quality and potential human health impacts by airborne metals and PAHs across an urban environment, particularly at locations that are not continuously covered by (non-)automated air quality measurement programmes.


Assuntos
Poluentes Atmosféricos , Líquens , Neoplasias , Hidrocarbonetos Policíclicos Aromáticos , Adulto , Criança , Humanos , Hidrocarbonetos Policíclicos Aromáticos/análise , Emissões de Veículos/análise , Poluentes Atmosféricos/análise , Monitoramento Biológico , Monitoramento Ambiental , Metais/análise , Reino Unido , Medição de Risco
9.
Trials ; 25(1): 141, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38389089

RESUMO

BACKGROUND: Over 3000 young people under the age of 18 are admitted to Tier 4 Child and Adolescent Mental Health Services (CAMHS) inpatient units across the UK each year. The average length of hospital stay for young people across all psychiatric units in the UK is 120 days. Research is needed to identify the most effective and efficient ways to care for young people (YP) with psychiatric emergencies. This study aims to evaluate the clinical effectiveness and cost-effectiveness of intensive community care service (ICCS) compared to treatment as usual (TAU) for young people with psychiatric emergencies. METHODS: This is a multicentre two-arm randomized controlled trial (RCT) with an internal pilot phase. Young people aged 12 to < 18 considered for admission at participating NHS organizations across the UK will be randomized 1:1 to either TAU or ICCS. The primary outcome is the time to return to or start education, employment, or training (EET) at 6 months post-randomization. Secondary outcomes will include evaluations of mental health and overall well-being and patient satisfaction. Service use and costs and cost-effectiveness will also be explored. Intention-to-treat analysis will be adopted. The trial is expected to be completed within 42 months, with an internal pilot phase in the first 12 months to assess the recruitment feasibility. A process evaluation using visual semi-structured interviews will be conducted with 42 young people and 42 healthcare workers. DISCUSSION: This trial is the first well-powered randomized controlled trial evaluating the clinical and cost-effectiveness of ICCS compared to TAU for young people with psychiatric emergencies in Great Britain. TRIAL REGISTRATION: ISRCTN ISRCTN42999542, Registration on April 29, 2020.


Assuntos
Emergências , Saúde Mental , Criança , Adolescente , Humanos , Resultado do Tratamento , Satisfação do Paciente , Reino Unido , Análise Custo-Benefício , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
10.
Polymers (Basel) ; 16(3)2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38337324

RESUMO

The growth of cracks between plies, i.e., delamination, in continuous fibre polymer matrix composites under cyclic-fatigue loading in operational aircraft structures has always been a very important factor, which has the potential to significantly decrease the service life of such structures. Whilst current designs are based on a 'no growth' design philosophy, delamination growth can nevertheless arise in operational aircraft and compromise structural integrity. To this end, the present paper outlines experimental and data reduction procedures for continuous fibre polymer matrix composites, based on a linear elastic fracture mechanics approach, which are capable of (a) determining and computing the fatigue crack growth (FCG) rate, da/dN, curve; (b) providing two different methods for determining the mandated worst-case FCG rate curve; and (c) calculating the fatigue threshold limit, below which no significant FCG occurs. Two data reduction procedures are proposed, which are based upon the Hartman-Schijve approach and a novel simple-scaling approach. These two different methodologies provide similar worst-case curves, and both provide an upper bound for all the experimental data. The calculated FCG threshold values as determined from both methodologies are also in very good agreement.

12.
J Pharm Sci ; 113(3): 826-835, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38042346

RESUMO

Tumor binding is an important parameter to derive unbound tumor concentration to explore pharmacokinetics (PK) and pharmacodynamics (PD) relationships for oncology disease targets. Tumor binding was evaluated using eleven matrices, including various commonly used ex vivo human and mouse xenograft and syngeneic tumors, tumor cell lines and liver as a surrogate tissue. The results showed that tumor binding is highly correlated among the different tumors and tumor cell lines except for the mouse melanoma (B16F10) tumor type. Liver fraction unbound (fu) has a good correlation with B16F10 tumor binding. Liver also demonstrates a two-fold equivalency, on average, with binding of other tumor types when a scaling factor is applied. Predictive models were developed for tumor binding, with correlations established with LogD (acids), predicted muscle fu (neutrals) and measured plasma protein binding (bases) to estimate tumor fu when experimental data are not available. Many approaches can be applied to obtain and estimate tumor binding values. One strategy proposed is to use a surrogate tumor tissue, such as mouse xenograft ovarian cancer (OVCAR3) tumor, as a surrogate for tumor binding (except for B16F10) to provide an early assessment of unbound tumor concentrations for development of PK/PD relationships.


Assuntos
Apoptose , Neoplasias Ovarianas , Humanos , Camundongos , Animais , Feminino , Linhagem Celular Tumoral , Proteínas Sanguíneas/metabolismo , Ligação Proteica , Descoberta de Drogas
13.
JCPP Adv ; 3(4): e12182, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38054049

RESUMO

Background: Parental depression increases risk for anxiety and depression in offspring. The transition from adolescence to adulthood is a common risk period for onset of such disorders. However, relatively few studies have considered development of these disorders from childhood to adulthood including multiple assessments during this transition period. Method: Offspring of depressed parents aged 9-17 years at baseline were followed prospectively for 13 years (n = 337). Average length of follow-up was 16 months between the first and second waves, 13 months between the second and third, and 8 years between the third and fourth. Current (3-month) psychopathology was assessed at each wave using diagnostic interviews. We derived estimates of 3-month prevalence, age at first diagnosis, course and comorbidity of disorders. Social functioning in adult life was assessed at the final wave and we assessed how prior and current disorder impacted adult functioning. Results: A quarter of young people met criteria for a mood disorder and a third for anxiety disorder at least once. Mood and anxiety disorder prevalence increased from 4.5% and 15.8% respectively in childhood (9-11 years) to 22.3% and 20.9% respectively by age 23-28. Increased prevalence across the transition from adolescence to adulthood was particularly marked in males, while prevalence increased earlier in adolescence in females. Age at first diagnosis varied widely (mood disorder mean = 16.5 years (range 9-26); anxiety disorder mean = 14.5 years (range 9-28)). Over half (52%) reported functional impairment in early adulthood, 31% harmful alcohol use, and 10% self-harm or a suicide attempt. Both previous and current mood or anxiety disorder were associated with functional impairment in early adulthood. Conclusions: There is a prolonged risk period for mood and anxiety disorders in this group, with prevalence peaking in early adulthood. This highlights the need for prolonged vigilance and effective targeted interventions in the offspring of depressed parents.

14.
Clin Ophthalmol ; 17: 3177-3187, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37901284

RESUMO

Purpose: To assess the "real world" utility of repeated injection with the dexamethasone intravitreal implant (DEX) in routine practice. Methods: This was a retrospective, single-center analysis of consecutive patients with diabetic macular edema, or macular edema following retinal vein occlusion, treated with DEX. None had received prior intravitreal steroid treatment. DEX was implanted as per the manufacturer's instructions. Results: Seventy-eight individuals (95 eyes) were included (50.0% female; mean age: 68.1 ± 12.4 years; mean duration of macular edema: 13.2 ± 12.9 months). Thirty-three eyes (34.7%) had received previous treatment with an anti-vascular endothelial growth factor (anti-VEGF) and/or laser. Thirty eyes (31.6%) underwent one round of DEX implantation; the remainder received 2-5 cycles (total: 225 cycles). Initial DEX treatment led to significant increases in visual acuity (VA) at 6 weeks (mean change: 4.6 letters; P=0.004). Greater VA improvements during the first treatment cycle were associated with inferior baseline VA (P=0.02), borderline associated with baseline central macular thickness (CMT; P=0.06), and independent of prior anti-VEGF treatment (P=0.39). In an analysis of all DEX injections, VA improvements were robust across cycles 1 and 2 but reduced in cycle 3 (P=0.03). CMT improvements did not differ based on injection number (P=0.20). Increases in intraocular pressure (IOP) were largest over the first 6 weeks (but rebounded towards baseline more rapidly) in cycle 1 versus cycles 2 and 3 (P<0.001). IOP rises were typically manageable with topical medications. Conclusion: This analysis confirms the broad utility of DEX and may inform decision-making in routine practice.

16.
Bioresour Technol ; 388: 129726, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37690217

RESUMO

Production of volatile fatty acids from food waste and lignocellulosic materials has potential to avoid emissions from their production from petrochemicals and provide valuable feedstocks. Techno-economic and life cycle assessments of using food waste and grass to produce volatile fatty acids through anaerobic digestion have been conducted. Uncertainty and sensitivity analysis for both assessments were done to enable a robust forecast of key-aspects of the technology deployment at industrial scale. Results show low environmental impact of volatile fatty acid with food wastes being the most beneficial feedstock with global warming potential varying from -0.21 to 0.01 CO2 eq./kg of product. Food wastes had the greatest economic benefit with a breakeven selling price of 1.11-1.94 GBP/kg (1.22-2.33 USD) of volatile fatty acids in the product solution determined through sensitivity analysis. Anaerobic digestion of wastes is therefore a promising alternative to traditional volatile fatty acid production routes, providing economic and environmental benefits.

17.
Vet Parasitol ; 322: 110026, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37713957

RESUMO

Targeted Selective Treatment (TST) is a gastrointestinal nematode (GIN) control strategy where anthelmintic treatment decisions are made at an individual animal level. TST has been proven to reduce anthelmintic use and subsequently slow down anthelmintic resistance development, however questions remain regarding optimal TST methods and their applicability across farms. In this study, the influence of Mineral and Vitamin (MV) supplementation on optimal energy utilisation (EU) TST thresholds was assessed on three Welsh farms. In total, 360 lambs were split into two groups, MV supplemented and control, and were treated with an anthelmintic against GIN at the midway point of the experiment. Lambs that improved their EU efficiency post treatment were deemed to have benefited from anthelmintic treatment. Optimal EU TST thresholds was determined for each treatment group per farm using Youden's J statistic where the treatment threshold retrospectively exhibiting the greatest combined sensitivity and specificity in correctly identifying lambs benefiting from treatment was deemed to be optimal. Results demonstrated that the optimal EU TST threshold was higher in MV supplemented groups at 0.72, 0.71 and 0.56 versus 0.58, 0.67, 0.51 for control groups on each respective farm. Identification of lambs for TST was more effective when using an optimised EU TST threshold, compared to when using the standard EU TST threshold of 0.66. The study highlights that applying standard EU TST thresholds may not be appropriate on all commercial farms with factors including MV status as noted in this study likely to influence optimal EU TST thresholds. Additional refinement of TST systems can further strengthen their applicability across sheep flocks.


Assuntos
Anti-Helmínticos , Nematoides , Infecções por Nematoides , Doenças dos Ovinos , Animais , Ovinos , Vitaminas/uso terapêutico , Estudos Retrospectivos , Anti-Helmínticos/uso terapêutico , Vitamina A , Strongyloides , Vitamina K/uso terapêutico , Minerais/uso terapêutico , Suplementos Nutricionais , Doenças dos Ovinos/tratamento farmacológico , Doenças dos Ovinos/prevenção & controle , Fezes , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/prevenção & controle , Infecções por Nematoides/veterinária , Contagem de Ovos de Parasitas/veterinária
18.
Cell Chem Biol ; 30(10): 1191-1210.e20, 2023 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-37557181

RESUMO

KAT6A, and its paralog KAT6B, are histone lysine acetyltransferases (HAT) that acetylate histone H3K23 and exert an oncogenic role in several tumor types including breast cancer where KAT6A is frequently amplified/overexpressed. However, pharmacologic targeting of KAT6A to achieve therapeutic benefit has been a challenge. Here we describe identification of a highly potent, selective, and orally bioavailable KAT6A/KAT6B inhibitor CTx-648 (PF-9363), derived from a benzisoxazole series, which demonstrates anti-tumor activity in correlation with H3K23Ac inhibition in KAT6A over-expressing breast cancer. Transcriptional and epigenetic profiling studies show reduced RNA Pol II binding and downregulation of genes involved in estrogen signaling, cell cycle, Myc and stem cell pathways associated with CTx-648 anti-tumor activity in ER-positive (ER+) breast cancer. CTx-648 treatment leads to potent tumor growth inhibition in ER+ breast cancer in vivo models, including models refractory to endocrine therapy, highlighting the potential for targeting KAT6A in ER+ breast cancer.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Neoplasias da Mama/genética , Histonas/metabolismo , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Transdução de Sinais , Linhagem Celular Tumoral
19.
PLoS One ; 18(7): e0288882, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37467238

RESUMO

Emotional disorders are common in childhood, and their prevalence sharply increases during adolescence. The Strengths and Difficulties Questionnaire (SDQ) is widely used for screening emotional and behavioural difficulties in children and young people, but little is known about the accuracy of the emotional subscale (SDQ-E) in detecting emotional disorders, and whether this changes over development. Such knowledge is important in determining whether symptom changes across age are due to developmental or measurement differences. This study assessed the validity of the SDQ-E and two individual items (low mood and general worry) in differentiating between cases and non-cases of Major Depressive Disorder (MDD), Generalised Anxiety Disorder (GAD), and other anxiety disorders across ages 7, 10, 13, 15, and 25 years in a UK population cohort. Analyses showed moderate accuracy of the subscale in discriminating cases of MDD (AUC = 0.67-0.85), and high accuracy for discriminating cases of GAD (AUC = 0.80-0.93) and any anxiety disorder (AUC = 0.74-0.83) compared to non-cases. The SDQ-E performed well across ages and sex, and generally performed better than the two individual items. Together our findings validate the SDQ-E as a screen for emotional disorders during childhood, adolescence, and early adulthood, and as a tool for longitudinal research on depression and anxiety disorders.


Assuntos
Depressão , Transtorno Depressivo Maior , Criança , Adolescente , Humanos , Adulto , Depressão/diagnóstico , Depressão/psicologia , Transtorno Depressivo Maior/diagnóstico , Inquéritos e Questionários , Ansiedade/diagnóstico , Ansiedade/psicologia , Transtornos de Ansiedade/diagnóstico , Psicometria
20.
Drug Metab Dispos ; 51(10): 1419-1427, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37429728

RESUMO

The metabolism of lufotrelvir, a novel phosphate prodrug of PF-00835231 for the treatment of COVID-19, was evaluated in healthy human volunteers and clinical trial participants with COVID-19 following intravenous infusion. The prodrug was completely converted to PF-00835231 that was subsequently cleared by hydrolysis, hydroxylation, ketoreduction, epimerization, renal clearance, and secretion into the feces. The main circulating metabolite was a hydrolysis product (M7) that was present at concentrations greater than PF-00835231, and this was consistent between healthy volunteers and participants with COVID-19. On administration of [14C]lufotrelvir, only 63% of the dose was obtained in excreta over 10 days and total drug-related material demonstrated a prolonged terminal phase half-life in plasma. A considerable portion of the labeled material was unextractable from fecal homogenate and plasma. The position of the carbon-14 atom in the labeled material was at a leucine carbonyl, and pronase digestion of the pellet derived from extraction of the fecal homogenate showed that [14C]leucine was released. SIGNIFICANCE STATEMENT: Lufotrelvir is an experimental phosphate prodrug intravenous therapy investigated for the potential treatment of COVID-19 in a hospital setting. The overall metabolism of lufotrelvir was determined in human healthy volunteers and clinical trial participants with COVID-19. Conversion of the phosphate prodrug to the active drug PF-00835231 was complete and the subsequent metabolic clearance of the active drug was largely via amide bond hydrolysis. Substantial drug-related material was not recovered due to loss of the carbon-14 label to endogenous metabolism.


Assuntos
COVID-19 , Pró-Fármacos , Humanos , Radioisótopos de Carbono/análise , Infusões Intravenosas , RNA Viral/análise , Leucina , SARS-CoV-2 , Administração Intravenosa , Fosfatos , Fezes/química
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