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1.
J Am Chem Soc ; 146(18): 12595-12600, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38682306

RESUMO

Chemical reactions are often characterized by their transition state, which defines the critical geometry the molecule must pass through to move from reactants to products. Roaming provides an alternative picture, where in a dissociation reaction, the bond breaking is frustrated and a loosely bound intermediate is formed. Following bond breaking, the two partners are seen to roam around each other at distances of several Ångstroms, forming a loosely bound, and structurally ill-defined, intermediate that can subsequently lead to reactive or unreactive collisions. Here, we present a direct and time-resolved experimental measurement of roaming. By measuring the photoelectron spectrum of UV-excited acetaldehyde with a femtosecond extreme ultraviolet pulse, we captured spectral signatures of all of the key reactive structures, including that of the roaming intermediate. This provided a direct experimental measurement of the roaming process and allowed us to identify the time scales by which the roaming intermediate is formed and removed and the electronic potential surfaces upon which roaming proceeds.

2.
Value Health ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38852668

RESUMO

OBJECTIVES: Prior work identified 6 key value elements (attributes of treatment and desired outcomes) for individuals living with major depressive disorder (MDD) in managing their condition: mode of treatment, time to treatment helpfulness, MDD relief, quality of work, interaction with others, and affordability. The objective of our study was to identify whether previous cost-effectiveness analyses (CEAs) for MDD treatment addressed any of these value elements. A secondary objective was to identify whether any study engaged patients, family members, and caregivers in the model development process. METHODS: We conducted a systematic literature review to identify published model-based CEAs. We compared the elements of the published studies with the MDD patient value elements elicited in prior work to identify gaps and areas for future research. RESULTS: Of 86 published CEAs, we found that 7 included patient out-of-pocket costs, and 32 included measures of productivity, which were both priorities for individuals with MDD. We found that only 2 studies elicited measures from patients for their model, and 2 studies engaged patients in the modeling process. CONCLUSIONS: Published CEA models for MDD treatment do not regularly include value elements that are a priority for this patient population nor do they include patients in their modeling process. Flexible models that can accommodate elements consistent with patient experience are needed, and a multistakeholder engagement approach would help accomplish this.

3.
Value Health ; 26(6): 823-832, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36529422

RESUMO

OBJECTIVES: Nadofaragene firadenovec is a gene therapy for bacillus Calmette-Guérin (BCG)-unresponsive non-muscle-invasive bladder cancer (NMIBC) undergoing Food and Drug Administration review. Pembrolizumab is approved for treating patients with BCG-unresponsive NMIBC with carcinoma in situ (CIS). We evaluated the cost-effectiveness of these treatments compared with a hypothetical therapeutic alternative, at a willingness-to-pay threshold of $150 000 per quality-adjusted life-year (QALY) gained, in CIS and non-CIS BCG-unresponsive NMIBC populations. METHODS: We developed a Markov cohort simulation model with a 3-month cycle length and lifetime horizon to estimate the total costs, QALYs, and cost per additional QALY from the health sector perspective. Clinical inputs were informed by results of single-arm clinical trials evaluating the treatments, and systematic literature reviews were conducted to obtain other model inputs. Sensitivity analyses were conducted to assess uncertainty in model results. RESULTS: Nadofaragene firadenovec, at a placeholder price 10% higher than the price of pembrolizumab, had an incremental cost-effectiveness ratio of $263 000 and $145 000 per QALY gained in CIS and non-CIS populations, respectively. Pembrolizumab had an incremental cost-effectiveness ratio of $168 000 per QALY gained for CIS. A 5.4% reduction in pembrolizumab's price would make it cost-effective. The model was sensitive to many inputs, especially to the probabilities of disease progression, initial treatment response and durability, and drug price. CONCLUSIONS: The cost-effectiveness of nadofaragene firadenovec will depend upon its price. Pembrolizumab, although not cost-effective in our base-case analysis, is an important alternative in this population with an unmet medical need. Comparative trials of these treatments are warranted to better estimate cost-effectiveness.


Assuntos
Antineoplásicos , Neoplasias não Músculo Invasivas da Bexiga , Neoplasias da Bexiga Urinária , Humanos , Vacina BCG/uso terapêutico , Análise Custo-Benefício , Neoplasias da Bexiga Urinária/tratamento farmacológico , Antineoplásicos/uso terapêutico , Imunoterapia , Anos de Vida Ajustados por Qualidade de Vida
4.
J Pharmacol Exp Ther ; 383(1): 103-116, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36507843

RESUMO

Treprostinil palmitil (TP), a long-acting inhaled pulmonary vasodilator prodrug of treprostinil (TRE), has beneficial effects in a Sugen5416/hypoxia (Su/Hx) rat model of pulmonary arterial hypertension (PAH) that compare favorably to the oral phosphodiesterase 5 inhibitor (PDE5) sildenafil. In this study in male Sprague-Dawley rats, a dry powder formulation of TP (TPIP) was compared with inhaled and intravenous TRE and oral selexipag to evaluate inhibition of hemodynamic and pathologic changes in the lungs and heart induced by Su/Hx challenge. Su (20 mg/kg) was injected subcutaneously followed by 3 weeks of Hx (10% O2/balance N2) and then initiation of test article administration over 5 weeks with room air breathing. Hemodynamics and histopathology were measured at the end of the study. Su/Hx challenge approximately doubled the mean pulmonary arterial blood pressure (mPAP) and the Fulton index, decreased cardiac output (CO), doubled the wall thickness and muscularization of the small (10-50 µm) and medium (51-100 µm) sized pulmonary arteries, and increased the percentage of obliterated pulmonary blood vessels. Even though inhaled TRE (65 µg/kg, 4× daily), intravenous TRE (810 ng/kg/min), and oral selexipag (30 mg/kg, twice daily) provided some beneficial effects against the Su/Hx challenge, the overall benefit was generally greater with TPIP at high dose (117 µg/kg, once daily). These results demonstrate that TPIP compares favorably to inhaled and intravenous TRE and oral selexipag with respect to inhibition of the pathophysiological changes induced by Su/Hx challenge in rats. SIGNIFICANCE STATEMENT: Treprostinil palmitil (TP) is a long-acting pulmonary vasodilator prodrug of treprostinil (TRE) formulated for inhaled administration by dry powder [treprostinil palmitil inhalation powder (TPIP)]. Comparison of the activity of TPIP, inhaled and intravenous TRE, and oral selexipag in a Sugen5416/hypoxia (Su/Hx) rat model of pulmonary arterial hypertension demonstrated that each of these drugs exert protection against the hemodynamic and histopathological changes induced by the Su/Hx challenge, with the greatest effect on these changes produced by TPIP.


Assuntos
Hipertensão Pulmonar , Pró-Fármacos , Hipertensão Arterial Pulmonar , Masculino , Ratos , Animais , Hipertensão Arterial Pulmonar/tratamento farmacológico , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Hipertensão Pulmonar/tratamento farmacológico , Ratos Sprague-Dawley , Administração por Inalação , Epoprostenol/farmacologia , Vasodilatadores , Hipóxia/tratamento farmacológico
5.
J Med Internet Res ; 24(7): e38584, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-35658098

RESUMO

BACKGROUND: Multiple types of biomedical associations of knowledge graphs, including COVID-19-related ones, are constructed based on co-occurring biomedical entities retrieved from recent literature. However, the applications derived from these raw graphs (eg, association predictions among genes, drugs, and diseases) have a high probability of false-positive predictions as co-occurrences in the literature do not always mean there is a true biomedical association between two entities. OBJECTIVE: Data quality plays an important role in training deep neural network models; however, most of the current work in this area has been focused on improving a model's performance with the assumption that the preprocessed data are clean. Here, we studied how to remove noise from raw knowledge graphs with limited labeled information. METHODS: The proposed framework used generative-based deep neural networks to generate a graph that can distinguish the unknown associations in the raw training graph. Two generative adversarial network models, NetGAN and Cross-Entropy Low-rank Logits (CELL), were adopted for the edge classification (ie, link prediction), leveraging unlabeled link information based on a real knowledge graph built from LitCovid and Pubtator. RESULTS: The performance of link prediction, especially in the extreme case of training data versus test data at a ratio of 1:9, demonstrated that the proposed method still achieved favorable results (area under the receiver operating characteristic curve >0.8 for the synthetic data set and 0.7 for the real data set), despite the limited amount of testing data available. CONCLUSIONS: Our preliminary findings showed the proposed framework achieved promising results for removing noise during data preprocessing of the biomedical knowledge graph, potentially improving the performance of downstream applications by providing cleaner data.


Assuntos
COVID-19 , Humanos , Conhecimento , Redes Neurais de Computação , Reconhecimento Automatizado de Padrão , Curva ROC
6.
Nano Lett ; 21(5): 1968-1975, 2021 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-33600187

RESUMO

The transition-metal dichalcogenide VSe2 exhibits an increased charge density wave transition temperature and an emerging insulating phase when thinned to a single layer. Here, we investigate the interplay of electronic and lattice degrees of freedom that underpin these phases in single-layer VSe2 using ultrafast pump-probe photoemission spectroscopy. In the insulating state, we observe a light-induced closure of the energy gap, which we disentangle from the ensuing hot carrier dynamics by fitting a model spectral function to the time-dependent photoemission intensity. This procedure leads to an estimated time scale of 480 fs for the closure of the gap, which suggests that the phase transition in single-layer VSe2 is driven by electron-lattice interactions rather than by Mott-like electronic effects. The ultrafast optical switching of these interactions in SL VSe2 demonstrates the potential for controlling phase transitions in 2D materials with light.

7.
J Appl Res Intellect Disabil ; 35(2): 471-479, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34729880

RESUMO

BACKGROUND: Mental health conditions are common among individuals with intellectual disability. Under recognition of mental health disorders leading to unmet treatment needs is common in this population. This article addresses one major contributing factor, the lack of cognitively accessible self-report measures for individuals with intellectual disability. METHOD: In this literature-informed overview of the state of the field, we discuss the need for, and complexities of, including individuals with intellectual disability in mental health assessments. RESULTS: With appropriate supports, many individuals with intellectual disability can respond to mental health questions. We discuss evidence-based strategies to make mental health assessments more accessible. CONCLUSION: We highlight the need to engage individuals with intellectual disability to provide first-hand information about their health and well-being. New instruments and research procedures should be developed in partnership with individuals with intellectual disability. Self-report may be essential to advancing the science of mental health research.


Assuntos
Deficiência Intelectual , Saúde Mental , Autorrelato , Humanos , Deficiência Intelectual/psicologia
8.
Antimicrob Agents Chemother ; 65(7): e0031621, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-33941518

RESUMO

Chronic pulmonary methicillin-resistant Staphylococcus aureus (MRSA) disease in cystic fibrosis (CF) has a high probability of recurrence following treatment with standard-of-care antibiotics and represents an area of unmet need associated with reduced life expectancy. We developed a lipoglycopeptide therapy customized for pulmonary delivery that not only demonstrates potent activity against planktonic MRSA, but also against protected colonies of MRSA in biofilms and within cells, the latter of which have been linked to clinical antibiotic failure. A library of next-generation potent lipoglycopeptides was synthesized with an emphasis on attaining superior pharmacokinetics (PK) and pharmacodynamics to similar compounds of their class. Our strategy focused on hydrophobic modification of vancomycin, where ester and amide functionality were included with carbonyl configuration and alkyl length as key variables. Candidates representative of each carbonyl attachment chemistry demonstrated potent activity in vitro, with several compounds being 30 to 60 times more potent than vancomycin. Selected compounds were advanced into in vivo nose-only inhalation PK evaluations in rats, where RV94, a potent lipoglycopeptide that utilizes an inverted amide linker to attach a 10-carbon chain to vancomycin, demonstrated the most favorable lung residence time after inhalation. Further in vitro evaluation of RV94 showed superior activity to vancomycin against an expanded panel of Gram-positive organisms, cellular accumulation and efficacy against intracellular MRSA, and MRSA biofilm killing. Moreover, in vivo efficacy of inhaled nebulized RV94 in a 48 h acute model of pulmonary MRSA (USA300) infection in neutropenic rats demonstrated statistically significant antibacterial activity that was superior to inhaled vancomycin.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Antibacterianos/uso terapêutico , Lipoglicopeptídeos , Pulmão , Testes de Sensibilidade Microbiana , Ratos , Infecções Estafilocócicas/tratamento farmacológico , Vancomicina
9.
Pulm Pharmacol Ther ; 66: 101983, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33346142

RESUMO

BACKGROUND: Treprostinil palmitil (TP) is an inhaled long-acting pulmonary vasodilator prodrug of treprostinil (TRE) that has been formulated for delivery as a suspension (treprostinil palmitil inhalation suspension; TPIS) and as a dry powder (treprostinil palmitil inhalation powder; TPIP). In humans, tachyphylaxis is frequently observed with continuous intravenous (IV) or subcutaneous (SC) infusion of TRE and requires dosage escalation to maintain activity. The aim of the present study was to determine whether tachyphylaxis occurs with repeat daily administration of inhaled TPIS. METHODS: Experiments were performed in male Sprague-Dawley rats prepared with a telemetry probe implanted into the right ventricle to measure the change in right ventricular pulse pressure (ΔRVPP) induced by exposure to a 10% oxygen gas mixture. TPIS (6 mL) at concentrations of 0.25, 0.5, and 1 mM was given by nose-only inhalation using an Aeroneb Pro nebulizer, either as a single administration or daily for 16 or 32 consecutive days. In studies involving consecutive daily administrations of TPIS, the delivered TP dosage was 140.3 µg/kg at 1 mM and ranged from 40.2 to 72.2 µg/kg at 0.5 mM. A separate cohort of telemetered rats received continuous IV infusion of TRE via an Alzet mini-pump at a dosage rate of 250 ng/kg/min for 16 days. Blood and lung tissue samples were obtained, and the concentration of TRE in the plasma and TRE and TP in the lungs were measured approximately 1 h after TPIS administration. RESULTS: Dose-response studies with TPIS administered as a single administration inhibited the hypoxia-induced increase in RVPP in both a concentration-dependent (0.25, 0.5, and 1 mM) and time-dependent (1-24 h) manner. TPIS, given QD or BID at inhaled doses ranging from 40.2 to 140.3 µg/kg for 16 or 32 consecutive days, produced statistically significant (P < .05) inhibition of the increase of RVPP due to hypoxia over the full duration of the dosing periods. By contrast, the inhibition of the hypoxia-induced increase in RVPP observed with IV TRE infusion (250 ng/kg/min) disappeared after 16 days of infusion. The plasma concentrations of TRE were significantly higher after IV TRE (range, 2.85-13.35 ng/mL) compared to inhaled TPIS (range, 0.22-0.73 ng/mL) CONCLUSIONS: There was no evidence of tachyphylaxis with repeat daily dosing of TPIS for a period of up to 32 days. The absence of tachyphylaxis with TPIS is likely related to its local vasodilatory effects within the lungs, combined with an absence of sustained high plasma concentrations of TRE.


Assuntos
Taquifilaxia , Vasodilatadores , Animais , Anti-Hipertensivos/uso terapêutico , Epoprostenol/análogos & derivados , Pulmão , Masculino , Ratos , Ratos Sprague-Dawley , Vasodilatadores/farmacologia
10.
Value Health ; 24(6): 839-845, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34119082

RESUMO

OBJECTIVES: To evaluate alternative methods to calculate and/or attribute economic surplus in the cost-effectiveness analysis of single or short-term therapies. METHODS: We performed a systematic literature review of articles describing alternative methods for cost-effectiveness analysis of potentially curative therapies whose assessment using traditional methods may suggest unaffordable valuations owing to the magnitude of estimated long-term quality-adjusted life-year (QALY) gains or cost offsets. Through internal deliberation and discussion with staff at the Health Technology Assessment bodies in England and Canada, we developed the following 3 alternative methods for further evaluation: (1) capping annual costs in the comparator arm at $150 000 per year; (2) "sharing" the economic surplus with the health sector by apportioning only 50% of cost offsets or 50% of cost offsets and QALY gains to the value of the therapy; and (3) crediting the therapy with only 12 years of the average annual cost offsets or cost offsets and QALY gains over the lifetime horizon. The impact of each alternative method was evaluated by applying it in an economic model of 3 hypothetical condition-treatment scenarios meant to reflect a diversity of chronicity and background healthcare costs. RESULTS: The alternative with greatest impact on threshold price for the fatal pediatric condition spinal muscular atrophy type 1 was the 12-year cutoff scenario. For a hypothetical one-time treatment for hemophilia A, capping cost offsets at $150 000 per year had the greatest impact. For chimeric antigen receptor T-cell treatment of non-Hodgkin's lymphoma, capping cost offsets or using 12-year threshold had little impact, whereas 50% sharing of surplus including QALY gains and cost offsets greatly reduced threshold pricing. CONCLUSIONS: Health Technology Assessment bodies and policy makers will wrestle with how to evaluate single or short-term potentially curative therapies and establish pricing and payment mechanisms to ensure sustainability. Scenario analyses using alternative methods for calculating and apportioning economic surplus can provide starkly different assessment results. These methods may stimulate important societal dialogue on fair pricing for these novel treatments.


Assuntos
Tratamento Farmacológico/economia , Terapia Genética/economia , Custos de Cuidados de Saúde , Imunoterapia Adotiva/economia , Avaliação da Tecnologia Biomédica/economia , Anticorpos Biespecíficos/economia , Anticorpos Biespecíficos/uso terapêutico , Anticorpos Monoclonais Humanizados/economia , Anticorpos Monoclonais Humanizados/uso terapêutico , Produtos Biológicos/economia , Produtos Biológicos/uso terapêutico , Redução de Custos , Análise Custo-Benefício , Custos de Medicamentos , Terapia Genética/efeitos adversos , Hemofilia A/tratamento farmacológico , Hemofilia A/economia , Humanos , Imunoterapia Adotiva/efeitos adversos , Linfoma não Hodgkin/economia , Linfoma não Hodgkin/terapia , Modelos Econômicos , Anos de Vida Ajustados por Qualidade de Vida , Proteínas Recombinantes de Fusão/economia , Proteínas Recombinantes de Fusão/uso terapêutico , Indução de Remissão , Atrofias Musculares Espinais da Infância/economia , Atrofias Musculares Espinais da Infância/genética , Atrofias Musculares Espinais da Infância/terapia , Fatores de Tempo , Resultado do Tratamento
11.
Prostaglandins Other Lipid Mediat ; 152: 106486, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33011365

RESUMO

Treprostinil (TRE) is a potent pulmonary vasodilator with effects on other pathological aspects of pulmonary arterial hypertension. In this study, the prostanoid receptors involved in TRE-induced relaxation of isolated rat pulmonary arteries and TRE-induced inhibition of increased gene expression in collagen synthesis and contractility of human lung fibroblasts were determined. TRE (0.01-100 µM) relaxed prostaglandin F2α-precontracted rat pulmonary arteries which was attenuated by denudation of the vascular endothelium. TRE-induced relaxation was predominantly blocked by the IP receptor antagonist RO3244194 (1 µM), with slightly greater inhibition in endothelium-denuded tissue. At higher TRE concentrations (> 1 µM), the DP1 receptor antagonist BW A868C (1 µM) also inhibited relaxation reaching significance above 10 µM. In contrast, the EP3 receptor antagonist L798106 (1 µM) accentuated TRE-induced relaxation of pulmonary arteries with intact endothelium. In human lung fibroblasts, the EP2 receptor antagonist PF-04418948 (1 µM) blocked transforming growth factor ß1 (TGF-ß1)-increased expression of collagen synthesis (COL1A1 and COL1A2) and fibroblast contractility (ACTG2) genes in presence of TRE (0.1 µM). In conclusion, the IP receptor located on rat pulmonary vascular smooth muscle and endothelium is the primary receptor mediating vasorelaxation, while the DP1 receptor present on the rat endothelium is involved only at higher TRE concentrations. In human lung fibroblasts, the EP2 receptor is the dominant receptor subtype involved in suppression of increased collagen synthesis and fibroblast contractility gene expression induced by TGF-ß1 in the presence of TRE.


Assuntos
Colágeno , Epoprostenol/análogos & derivados , Fibroblastos , Pulmão , Artéria Pulmonar , Vasodilatação , Animais , Masculino , Ratos
12.
J Chem Phys ; 154(3): 034302, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33499612

RESUMO

The products formed following the photodissociation of UV (200 nm) excited CS2 are monitored in a time resolved photoelectron spectroscopy experiment using femtosecond XUV (21.5 eV) photons. By spectrally resolving the electrons, we identify separate photoelectron bands related to the CS2 + hν → S(1D) + CS and CS2 + hν → S(3P) + CS dissociation channels, which show different appearance and rise times. The measurements show that there is no delay in the appearance of the S(1D) product contrary to the results of Horio et al. [J. Chem. Phys. 147, 013932 (2017)]. Analysis of the photoelectron yield associated with the atomic products allows us to obtain a S(3P)/S(1D) branching ratio and the rate constants associated with dissociation and intersystem crossing rather than the effective lifetime observed through the measurement of excited state populations alone.

13.
Int J Mol Sci ; 22(2)2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33430435

RESUMO

Treprostinil palmitil (TP) is a prodrug of treprostinil (TRE), a pulmonary vasodilator that has been previously formulated for inhaled administration via a nebulizer. TP demonstrates a sustained presence in the lungs with reduced systemic exposure and prolonged inhibition of hypoxia-induced pulmonary vasoconstriction in vivo. Here, we report on re-formulation efforts to develop a more convenient solution-based metered-dose inhaler (MDI) formulation of TP, a treprostinil palmitil inhalation aerosol (TPIA) that matches the pharmacokinetic (PK) and efficacy profile of a nebulized TP formulation, treprostinil palmitil inhalation suspension (TPIS). MDI canisters were manufactured using a two-stage filling method. Aerosol performance, formulation solubility, and chemical stability assays were utilized for in vitro evaluation. For in vivo studies, TPIA formulations were delivered to rodents using an inhalation tower modified for MDI delivery. Using an iterative process involving evaluation of formulation performance in vitro (TP and excipient solubility, chemical stability, physical stability, and aerosol properties) and confirmatory testing in vivo (rat PK and efficacy, guinea pig cough), a promising formulation was identified. The optimized formulation, TPIA-W, demonstrates uniform in vitro drug delivery, a PK profile suitable for a once-daily administration, efficacy lasting at least 12 h in a hypoxic challenge model, and a significantly higher cough threshold than the parent drug treprostinil.


Assuntos
Aerossóis/farmacologia , Epoprostenol/análogos & derivados , Pró-Fármacos/farmacologia , Hipertensão Arterial Pulmonar/tratamento farmacológico , Administração por Inalação , Animais , Modelos Animais de Doenças , Composição de Medicamentos , Epoprostenol/química , Epoprostenol/farmacologia , Cobaias , Humanos , Nanopartículas/química , Pró-Fármacos/química , Hipertensão Arterial Pulmonar/patologia , Ratos , Vasoconstrição/efeitos dos fármacos , Vasodilatadores/química , Vasodilatadores/farmacologia
14.
Pulm Pharmacol Ther ; 65: 102002, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33596473

RESUMO

Treprostinil (TRE) is a prostanoid analog pulmonary vasodilator drug marketed with subcutaneous, intravenous (i.v.), oral, and inhaled routes of administration for the treatment of pulmonary arterial hypertension (PAH). Due to its short half-life, TRE requires either continuous infusion or multiple dosing, which exacerbates its side effects. Therefore, a long-acting prostanoid analog that maintains the positive attributes of TRE but has fewer TRE-related side effects could be of clinical benefit. In this report, we describe the discovery, preclinical development, and biology of the TRE ester prodrug, treprostinil palmitil (TP), which is formulated in a lipid nanoparticle (LNP) for administration as a nebulized inhaled suspension (TPIS). In screening assays focused on the conversion of prodrug to TRE, TP (16 carbon alkyl chain) had the slowest rate of conversion compared with short-alkyl chain TRE prodrugs (i.e., 2-8 carbon alkyl chain). Furthermore, TP is a pure prodrug and possesses no inherent binding to G-protein coupled receptors including prostanoid receptors. Pharmacokinetic studies in rats and dogs demonstrated that TPIS maintained relatively high concentrations of TP in the lungs yet had a low maximum plasma concentrations (Cmax) of both TP and, more importantly, the active product, TRE. Efficacy studies in rats and dogs demonstrated inhibition of pulmonary vasoconstriction induced by exposure to hypoxic air or i.v.-infused U46619 (thromboxane mimetic) over 24 h with TPIS. Cough was not observed with TPIS at an equivalent dose at which TRE caused cough in guinea pigs and dogs, and there was no evidence of desensitization to the inhibition of pulmonary vasoconstriction in rats with repeat inhaled dosing. TPIS was also more efficacious than i.v.-infused TRE in a sugen/hypoxia rat model of PAH to inhibit pulmonary vascular remodeling, an effect likely driven by local activities of TRE within the lungs. TPIS also demonstrated antifibrotic and anti-inflammatory activity in the lungs in rodent models of pulmonary fibrosis and asthma. In a phase 1 study in healthy human participants, TPIS (referred to as INS1009) had a lower plasma TRE Cmax and fewer respiratory-related side effects at equimolar doses compared with inhaled TRE. We have now formulated TP as an aerosol powder for delivery by a dry powder inhaler (referred to as treprostinil palmitil inhalation powder-TPIP), and as an aerosol solution in a fluorohydrocarbon solvent for delivery by a metered dose inhaler. These options may reduce drug administration time and involve less device maintenance compared with delivery by nebulization.


Assuntos
Pró-Fármacos , Animais , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Biologia , Cães , Epoprostenol/análogos & derivados , Cobaias , Ratos
15.
Value Health ; 23(10): 1332-1339, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33032777

RESUMO

OBJECTIVES: Cystic fibrosis (CF) is a rare genetic disease with no cure. Until recently, treatment has targeted symptoms of the disease and not the disease-causing genetic defect. Ivacaftor is included in a new class of breakthrough drugs targeting the genetic defects of CF. We sought to estimate the long-term cost-effectiveness of ivacaftor from a US payer perspective. METHODS: We developed an individual-level microsimulation model that followed a cohort of heterogeneous US CF patients over a lifetime. The primary outcome of interest was quality-adjusted life years (QALYs). We also compared unadjusted life years, count of acute pulmonary exacerbations, and count of lung transplants over a lifetime between patients treated with ivacaftor plus best supportive care and patients treated with best supportive care alone. We conducted one-way and probabilistic sensitivity analyses to test the impact of various model inputs and uncertainties. RESULTS: We found a substantial increase in QALYs, life years, and treatment costs over a lifetime for patients treated with ivacaftor plus best supportive care versus best supportive care alone. Discounted results for ivacaftor were 22.92 QALYs and $8 797 840 in total lifetime costs compared to 16.12 QALYs and $2 336 366 lifetime costs for best supportive care alone. The incremental cost-effectiveness ratios (ICERs) were $950 217 per QALY. Results from the probabilistic sensitivity analysis indicated a 0% chance that ivacaftor was cost-effective at a willingness-to-pay (WTP) threshold of $500 000 per QALY. CONCLUSIONS: Treatment with ivacaftor plus best supportive care versus best supportive care alone is not cost-effective at or near commonly accepted WTP thresholds.


Assuntos
Aminofenóis/uso terapêutico , Agonistas dos Canais de Cloreto/uso terapêutico , Fibrose Cística/economia , Custos de Cuidados de Saúde/estatística & dados numéricos , Quinolonas/uso terapêutico , Aminofenóis/economia , Agonistas dos Canais de Cloreto/economia , Análise Custo-Benefício , Fibrose Cística/tratamento farmacológico , Fibrose Cística/genética , Custos de Medicamentos , Feminino , Humanos , Masculino , Mutação/genética , Anos de Vida Ajustados por Qualidade de Vida , Quinolonas/economia , Fatores de Tempo
16.
Cost Eff Resour Alloc ; 18: 41, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33041673

RESUMO

BACKGROUND: Patients with infantile-onset spinal muscular atrophy (SMA), a rare, genetic neuromuscular disease, do not achieve key motor function milestones (e.g., sitting) and have short life expectancy in the absence of treatment. Nusinersen is a disease-modifying therapy for patients with SMA. OBJECTIVE: The aim of this study was to estimate the cost-effectiveness of nusinersen compared to best supportive care (BSC) in patients diagnosed with infantile-onset SMA in the US. METHODS: A de novo economic model was developed with the following health states: "permanent ventilation", "not sitting", "sitting", "walking", and "death". Short-term data were sourced from the pivotal clinical trials and studies of nusinersen (ENDEAR and SHINE). Motor function milestones achieved at the end of follow-up in the clinical trials were assumed to be sustained until death. Mortality risks were based on survival modelling of relevant published Kaplan-Meier data. Costs, life years (LYs), and quality-adjusted life years (QALYs) were discounted at 3% per annum, and the analyses were performed from a US health care sector perspective. Scenario analyses and sensitivity analyses were conducted to assess the robustness of the results to key parameters. RESULTS: In our base-case analysis, nusinersen treatment achieves greater QALYs and more LYs (3.24 and 7.64, respectively) compared with BSC (0.46 QALYs and 2.40 LYs, respectively), resulting in an incremental cost per QALY gained of approximately $1,112,000 and an incremental cost per LY gained of $590,000 for nusinersen compared to BSC. The incremental cost effectiveness ratios did not fall below $990,000 per QALY gained in scenario and sensitivity analyses. Results were most sensitive to the length of survival, background health care costs, and utility in the "not sitting" and "sitting" health states. CONCLUSIONS: The estimated incremental cost-effectiveness of nusinersen from a US health care sector perspective exceeded traditional cost-effectiveness thresholds. Cost-effectiveness was dependent on assumptions made regarding survival, costs, utilities, and whether the motor function milestones were sustained over lifetime. Given the relatively short-term effectiveness data available for the treatment, a registry to collect long-term data of infantile-onset SMA patients is recommended.

17.
Phys Chem Chem Phys ; 22(44): 25695-25703, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33146165

RESUMO

Femtosecond pump-probe photoelectron spectroscopy measurements using an extreme ultraviolet probe have been made on the photodissociation dynamics of UV (269 nm) excited CH3I. The UV excitation leads to population of the 3Q0 state which rapidly dissociates. The dissociation is manifested as shifts in the measured photoelectron kinetic energy that map the extending C-I bond. The increased energy available in the XUV probe relative to a UV probe means the dynamics are followed over the chemically important region as far as C-I bond lengths of approximately 4 Å.

18.
Value Health ; 22(6): 656-660, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31198182

RESUMO

Evaluating different approaches to assessing the clinical effectiveness and value of potential cures will be essential to arm the policymaker, payer, and manufacturer communities with a platform that can reward innovation while supporting a sustainable health insurance system. Potential cures will accentuate concerns about substantial uncertainty in long-term outcomes. They will also focus attention on whether broader elements of value need to be incorporated and whether specific social values have a special place in evaluations of potential cures. In addition, the large magnitudes of potential health gain and cost offsets may require new methods before translation into value-based price recommendations. This article analyzes the challenges and presents several options to modify the conduct and presentation of cost-effectiveness analyses to ensure they provide policy-relevant assessments of the value of potential cures.


Assuntos
Análise Custo-Benefício/métodos , Seguro de Saúde Baseado em Valor/economia , Análise Custo-Benefício/tendências , Humanos , Estados Unidos
19.
Value Health ; 22(4): 416-422, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30975392

RESUMO

OBJECTIVE: Opioid abuse is a significant public health problem in the United States. We evaluate the clinical effectiveness and economic impact of abuse-deterrent formulations (ADF) of opioids relative to non-ADF opioids in preventing abuse. METHODS: We developed a cost-effectiveness model simulating 2 cohorts of 100 000 noncancer, chronic-pain patients newly prescribed either ADF or non-ADF extended-release (ER) opioids and followed them over 5 years, tracking new events of opioid abuse and opioid-related overdose deaths in addition to tracking 5-year cumulative costs of therapeutic use and abuse of ADF and non-ADF opioids. Patients in each cohort entered the model for therapeutic opioid use from where they could continue in that pathway, discontinue opioid use, or abuse opioids or die of opioid overdose-related or unrelated causes. In addition, one-way sensitivity and scenario analysis were conducted. RESULTS: Over a 5-year time period, using ADF opioids prevented an additional 2300 new cases of opioid abuse at an additional cost of approximately $535 million to the healthcare sector. Threshold analyses showed that a 40% decrease in ADF opioid costs was required to attain cost neutrality between the 2 cohorts, whereas a 100% effectiveness in abuse reduction still did not result in cost neutrality. A 43% decrease in diversion with ADFs relative to non-ADFs was required to attain cost neutrality. Including a societal perspective produced results directionally similar to the base-case analysis findings. CONCLUSION: ADF opioids have the potential to prevent new cases of opioid abuse, but at substantially higher costs to the health system.


Assuntos
Formulações de Dissuasão de Abuso/economia , Analgésicos Opioides/economia , Analgésicos Opioides/uso terapêutico , Dor Crônica/tratamento farmacológico , Dor Crônica/economia , Custos de Medicamentos , Transtornos Relacionados ao Uso de Opioides/economia , Transtornos Relacionados ao Uso de Opioides/prevenção & controle , Uso Indevido de Medicamentos sob Prescrição/economia , Uso Indevido de Medicamentos sob Prescrição/prevenção & controle , Formulações de Dissuasão de Abuso/efeitos adversos , Analgésicos Opioides/efeitos adversos , Dor Crônica/epidemiologia , Análise Custo-Benefício , Composição de Medicamentos , Humanos , Incidência , Modelos Econômicos , Transtornos Relacionados ao Uso de Opioides/epidemiologia , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Estados Unidos/epidemiologia
20.
Value Health ; 22(2): 161-167, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30711060

RESUMO

OBJECTIVE: The gene therapy voretigene neparvovec (VN) is the first Food and Drug Administration-approved treatment for vision loss owing to the ultra-rare RPE65-mediated inherited retinal disorders. We modeled the cost-utility of VN compared with standard of care (SoC). STUDY DESIGN: A 2-state Markov model, alive and dead, with a lifetime horizon. METHODS: Visual acuity (VA) and visual field (VF) were tracked to model quality-adjusted life-years (QALYs). VN led to an improvement in VA and VF that we assumed was maintained for 10 years followed by a 10-year waning period. The cost of VN was $850 000, and other direct medical costs for depression and trauma were included for a US healthcare system perspective. A modified societal perspective also included direct nonmedical costs and indirect costs. RESULTS: VN provided an additional 1.3 QALYs over the remaining lifetime of an individual. The average total lifetime direct medical cost for individuals treated with VN was $1 039 000 compared with $213 400 for SoC, leading to an incremental cost-effectiveness ratio (ICER) of $643 800/QALY from the US healthcare system perspective. Direct nonmedical costs totalled $1 070 900 for VN and $1 203 300 for SoC, and indirect costs totalled $405 400 for VN and $482 900 for SoC, leading to an ICER of $480 100/QALY from the modified societal perspective. CONCLUSIONS: At the current price, VN was unlikely to reach traditional cost-effectiveness standards compared with SoC. VN has important implications for both development and pricing of future gene therapies; therefore clinical and economic analyses must be carefully considered.


Assuntos
Alelos , Análise Custo-Benefício , Terapia Genética/economia , Doenças Retinianas/economia , Doenças Retinianas/terapia , cis-trans-Isomerases/economia , Adolescente , Adulto , Idoso , Análise Custo-Benefício/métodos , Feminino , Terapia Genética/métodos , Humanos , Masculino , Cadeias de Markov , Pessoa de Meia-Idade , Doenças Retinianas/genética , Transtornos da Visão/economia , Transtornos da Visão/genética , Transtornos da Visão/terapia , Adulto Jovem , cis-trans-Isomerases/administração & dosagem , cis-trans-Isomerases/genética
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