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1.
J Headache Pain ; 24(1): 69, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37296378

RESUMO

Migraine is a debilitating disorder, and while the introduction of monoclonal antibodies (mAbs) has led to efficacious and tolerable responses, a substantial number of patients are so-called "non-responders". We introduce reasons for this insufficient response, including insufficient blockade of Calcitonin Gene-Related Peptide (CGRP) or its receptor. We present a clinical case, i.e. a female migraine patient who mistakenly administered supratherapeutic (three-fold higher) doses of erenumab leading to more efficacious clinical responses without any side-effects. This example illustrates that the initial dosages might have been too low, resulting in a remaining undesired increased effect of CGRP. While a capsaicin forearm model has repeatedly been used to evaluate the pharmacokinetic-pharmacodynamic relationship of mAbs, we provide directions to revisit or reconsider dose-finding and dose-ranging of these drugs. These directions include (i) refinement and application of a capsaicin forehead model (instead of a forearm model) to study trigeminovascular activity and improve dosing, and (ii) reconsideration of trial populations. Indeed, the dose-finding studies were mainly performed in relatively young and normal-weight males, while most phase III/IV trials are marked by a high female-to-male ratio, mainly consisting of overweight to obese females. Considering these aspects in future trials could optimize healthcare for a larger proportion of migraine patients.


Assuntos
Anticorpos Monoclonais , Transtornos de Enxaqueca , Humanos , Masculino , Feminino , Anticorpos Monoclonais/uso terapêutico , Peptídeo Relacionado com Gene de Calcitonina/uso terapêutico , Capsaicina , Receptores de Peptídeo Relacionado com o Gene de Calcitonina , Transtornos de Enxaqueca/tratamento farmacológico
2.
Stat Med ; 41(7): 1157-1171, 2022 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-34747043

RESUMO

Estimation of the dose-response curve for efficacy and subsequent selection of an appropriate dose in phase II trials are important processes in drug development. Various methods have been investigated to estimate dose-response curves. Generally, these methods are used with equal allocation of subjects for simplicity; nevertheless, they may not fully optimize performance metrics because of nonoptimal allocation. Optimal allocation methods, which include adaptive allocation methods, have been proposed to overcome the limitations of equal allocation. However, they rely on asymptotics, and thus sometimes cannot efficiently optimize the performance metric with the sample size in an actual clinical trial. The purpose of this study is to construct an adaptive allocation rule that directly optimizes a performance metric, such as power, accuracy of model selection, accuracy of the estimated target dose, or mean absolute error over the estimated dose-response curve. We demonstrate that deep reinforcement learning with an appropriately defined state and reward can be used to construct such an adaptive allocation rule. The simulation study shows that the proposed method can successfully improve the performance metric to be optimized when compared with the equal allocation, D-optimal, and TD-optimal methods. In particular, when the mean absolute error was set to the metric to be optimized, it is possible to construct a rule that is superior for many metrics.


Assuntos
Desenvolvimento de Medicamentos , Projetos de Pesquisa , Simulação por Computador , Relação Dose-Resposta a Droga , Humanos , Tamanho da Amostra
3.
Biom J ; 62(7): 1717-1729, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32529689

RESUMO

While there is recognition that more informative clinical endpoints can support better decision-making in clinical trials, it remains a common practice to categorize endpoints originally measured on a continuous scale. The primary motivation for this categorization (and most commonly dichotomization) is the simplicity of the analysis. There is, however, a long argument that this simplicity can come at a high cost. Specifically, larger sample sizes are needed to achieve the same level of accuracy when using a dichotomized outcome instead of the original continuous endpoint. The degree of "loss of information" has been studied in the contexts of parallel-group designs and two-stage Phase II trials. Limited attention, however, has been given to the quantification of the associated losses in dose-ranging trials. In this work, we propose an approach to estimate the associated losses in Phase II dose-ranging trials that is free of the actual dose-ranging design used and depends on the clinical setting only. The approach uses the notion of a nonparametric optimal benchmark for dose-finding trials, an evaluation tool that facilitates the assessment of a dose-finding design by providing an upper bound on its performance under a given scenario in terms of the probability of the target dose selection. After demonstrating how the benchmark can be applied to Phase II dose-ranging trials, we use it to quantify the dichotomization losses. Using parameters from real clinical trials in various therapeutic areas, it is found that the ratio of sample sizes needed to obtain the same precision using continuous and binary (dichotomized) endpoints varies between 70% and 75% under the majority of scenarios but can drop to 50% in some cases.


Assuntos
Benchmarking , Relação Dose-Resposta a Droga , Projetos de Pesquisa , Ensaios Clínicos Fase II como Assunto , Simulação por Computador , Humanos , Probabilidade , Tamanho da Amostra
4.
J Stroke Cerebrovasc Dis ; 29(12): 105359, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33045625

RESUMO

INTRODUCTION: There is strong evidence that cardiorespiratory fitness (CRF) training improves fitness and mobility after stroke. Despite the large number of studies, the most efficacious dose is yet to be determined. Furthermore, the safety of early post-stroke training, while theoretically beneficial, remains uncertain. The aim of this study is to determine the maximum safe and tolerable intensity of CRF training early post-stroke. METHODS: This is a stratified (low to moderate exercise capacity), Phase I, 5+5 dose ranging trial protocol. Participants will be recruited within one month post-stroke and stratified by their exercise-capacity (i.e. low and moderate capacity). Cohorts of five participants will perform 12 interval-based training sessions for four-weeks at a pre-determined target-intensity. The intensity will increase in each consecutive cohort, in each stratum according to pre-defined rules until the maximum safe and tolerable intensity is reached, as determined by the occurrence of dose-limiting events and occurrence of adverse events. Dose-limiting events are defined as symptoms indicative of over-training including pain and inability to perform usual activities. STUDY OUTCOME: Maximum safe and tolerable intensity of CRF training in stroke survivors with low and moderate exercise capacity. DISCUSSION: This study is a first step in the systematic development of a CRF training intervention. We believe similar dose ranging designs may be useful for development of other rehabilitation interventions in different study populations.


Assuntos
Terapia por Exercício , Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral/terapia , Idoso , Idoso de 80 Anos ou mais , Ensaios Clínicos Fase I como Assunto , Terapia por Exercício/efeitos adversos , Tolerância ao Exercício , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Aptidão Física , Recuperação de Função Fisiológica , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/fisiopatologia , Reabilitação do Acidente Vascular Cerebral/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Vitória
5.
Stat Med ; 37(21): 3056-3077, 2018 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-29869347

RESUMO

Randomization designs for multiarm clinical trials are increasingly used in practice, especially in phase II dose-ranging studies. Many new methods have been proposed in the literature; however, there is lack of systematic, head-to-head comparison of the competing designs. In this paper, we systematically investigate statistical properties of various restricted randomization procedures for multiarm trials with fixed and possibly unequal allocation ratios. The design operating characteristics include measures of allocation balance, randomness of treatment assignments, variations in the allocation ratio, and statistical characteristics such as type I error rate and power. The results from the current paper should help clinical investigators select an appropriate randomization procedure for their clinical trial. We also provide a web-based R shiny application that can be used to reproduce all results in this paper and run simulations under additional user-defined experimental scenarios.


Assuntos
Modelos Estatísticos , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Projetos de Pesquisa , Simulação por Computador , Humanos
6.
Stat Med ; 37(22): 3244-3253, 2018 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-29926481

RESUMO

In Phase II clinical development of a new drug, the two most important deliverables are proof of concept (PoC) and dose ranging. Traditionally, a PoC study is designed as the first Phase II clinical trial. In this PoC, there are two treatment groups-a high dose of the study medication, against the placebo control. After the concept is proven, the next Phase II study is a dose-ranging design with many test doses. This paper proposes a two-stage design with the first stage attempting to generate an early signal of efficacy. If successful, the second stage will adopt a "Go Fast" plan to expand the current study and add lower study doses of the test drug to explore the efficacy dose range. Otherwise, a "Go Slow" strategy is triggered, and the study will stop at a reduced sample size with high dose and placebo only.


Assuntos
Ensaios Clínicos Fase II como Assunto , Modelos Estatísticos , Preparações Farmacêuticas/administração & dosagem , Estudo de Prova de Conceito , Humanos , Projetos de Pesquisa , Tamanho da Amostra
7.
J Am Acad Dermatol ; 79(2): 277-286.e10, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29609013

RESUMO

BACKGROUND: Neutralizing interleukin (IL) 17F in addition to IL-17A might provide a more complete and specific approach to inhibiting inflammation. OBJECTIVE: Assess the efficacy and safety of bimekizumab, a monoclonal antibody that potently and selectively neutralizes IL-17A and IL-17F, in patients with moderate-to-severe plaque psoriasis. METHODS: Double-blinded, placebo-controlled phase 2b study (NCT02905006). Patients (randomized 1:1:1:1:1:1) received subcutaneous bimekizumab every 4 weeks at doses of 64 mg, 160 mg, 160 mg with 320 mg loading dose, 320 mg, 480 mg, or placebo. Primary endpoint was ≥90% reduction in Psoriasis Area Severity Index (PASI90) at week 12. RESULTS: There was a significant (P < .0001) dose-dependent response for PASI90 (week 12); more patients achieved PASI90 in the bimekizumab groups (46.2%-79.1%) than patients in the placebo group (0%; P < .0001 all doses). Across all doses, there were significant improvements from baseline for all secondary endpoints (PASI90 week 8, PASI75 week 12, PASI100 week 12, and Investigators Global Assessment clear or almost clear weeks 8 and 12; P ≤ .0003) compared with placebo. More bimekizumab-treated patients than placebo-treated patients achieved PASI100 (week 12) (27.9%-60.0% vs 0%; P ≤ .0002 all doses). Treatment-emergent adverse events were reported by 126 of 208 (61%) bimekizumab-treated patients and 15 of 42 (36%) placebo-treated patients. LIMITATIONS: No active comparator. CONCLUSION: Dual neutralization of IL-17A and IL-17F with bimekizumab provided rapid and substantial clinical improvements in patients with psoriasis, with no unexpected or dose-related safety findings.


Assuntos
Anticorpos Monoclonais Humanizados/administração & dosagem , Fármacos Dermatológicos/administração & dosagem , Interleucina-17/antagonistas & inibidores , Psoríase/tratamento farmacológico , Psoríase/imunologia , Adulto , Anticorpos Monoclonais Humanizados/efeitos adversos , Doença Crônica , Fármacos Dermatológicos/efeitos adversos , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Resultado do Tratamento
8.
Clin Infect Dis ; 65(3): 442-452, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28369211

RESUMO

BACKGROUND: GSK3532795 is a second-generation human immunodeficiency virus type 1 (HIV-1) maturation inhibitor that targets HIV-1 Gag, inhibiting the final protease cleavage between capsid protein p24 and spacer protein-1, producing immature, noninfectious virions. METHODS: This was a phase 2a, randomized, dose-ranging multipart trial. In part A, subtype B-infected subjects received 5-120 mg GSK3532795 (or placebo) once daily for 10 days. In part B, subtype B-infected subjects received 40 mg or 80 mg GSK3532795 once daily with atazanavir (ATV) with or without (±) ritonavir (RTV) or standard of care (SOC) (tenofovir disoproxil fumarate 300 mg, emtricitabine 200 mg, and ATV/RTV 300 mg/100 mg) for 28 days. In part C, subtype C-infected subjects received 40 mg or 120 mg GSK3532795 once daily (or placebo) for 10 days. Endpoints included change in HIV-1 RNA from baseline on day 11 (parts A/C) or day 29 (part B). RESULTS: A >1 log10 median decline in HIV-1 RNA was achieved by day 11 in parts A and C and day 29 in part B at GSK3532795 doses ≥40 mg; part B subjects receiving GSK3532795 and ATV ± RTV achieved similar declines to those receiving SOC. Median of the maximum declines in HIV-1 RNA were similar for the 40-120 mg once-daily dose groups regardless of baseline Gag polymorphisms. There were no deaths, adverse events leading to discontinuation, or serious adverse events. CONCLUSIONS: GSK3532795 demonstrated potent antiviral activity against subtype B (monotherapy or with ATV ± RTV) and subtype C, and was generally well tolerated, which supported continued development of GSK3532795 in subjects with HIV-1 subtype B or subtype C. CLINICAL TRIALS REGISTRATION: NCT01803074.


Assuntos
Sulfato de Atazanavir , Infecções por HIV/tratamento farmacológico , Inibidores da Protease de HIV , Ritonavir , Adulto , Sulfato de Atazanavir/administração & dosagem , Sulfato de Atazanavir/efeitos adversos , Sulfato de Atazanavir/uso terapêutico , Feminino , Inibidores da Protease de HIV/administração & dosagem , Inibidores da Protease de HIV/efeitos adversos , Inibidores da Protease de HIV/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade , RNA Viral/sangue , Ritonavir/administração & dosagem , Ritonavir/efeitos adversos , Ritonavir/uso terapêutico , Adulto Jovem
9.
J Allergy Clin Immunol ; 138(2): 451-458.e5, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27289490

RESUMO

BACKGROUND: In a natural field study, sublingual tablets of house dust mite (HDM) allergen extracts (STG320) were efficacious in treating HDM-associated allergic rhinitis. OBJECTIVES: We sought to assess the efficacy and safety of 3 doses of STG320 in an environmental exposure chamber. METHODS: In this randomized, double-blind study, adults with HDM-associated allergic rhinitis were given a daily sublingual tablet containing placebo or STG320 at a dose of 500IR, 300IR, or 100IR (IR, index of reactivity) for 6 months. Participants recorded their rhinitis symptoms during 4-hour HDM EEC challenges at randomization and months 1, 2, 4, and 6. The primary efficacy end point was the change from baseline to end of treatment in the area under the curve of the rhinitis total symptom score (ChBLAUCRTSS 0-4h). Differences from the placebo group were analyzed by analysis of covariance. Adverse events (AEs) and routine safety parameters were recorded. RESULTS: A total of 355 subjects were randomized to 1 of 4 groups: 500IR (n = 93), 300IR (n = 86), 100IR (n = 89), or placebo (n = 87). The least squares mean differences from placebo in ChBLAUCRTSS 0-4h for the 500IR, 300IR, and 100IR groups indicated a dose-dependent effect, with reductions in symptom scores of 33%, 29%, and 20%, respectively. The most frequent AEs were throat irritation and oral pruritus. There were no reports of anaphylaxis or reports consistent with severe laryngopharyngeal disorders and no use of epinephrine. AEs leading to premature discontinuations were more common in the 500IR group. CONCLUSIONS: A dose-dependent effect of sublingual HDM immunotherapy was demonstrated in this environmental exposure chamber study, supporting further development of this treatment.


Assuntos
Antígenos de Dermatophagoides/imunologia , Rinite Alérgica/imunologia , Rinite Alérgica/terapia , Imunoterapia Sublingual , Adulto , Antígenos de Dermatophagoides/administração & dosagem , Área Sob a Curva , Exposição Ambiental , Feminino , Volume Expiratório Forçado , Humanos , Imunoglobulina E/imunologia , Imunoglobulina G/imunologia , Masculino , Rinite Alérgica/diagnóstico , Imunoterapia Sublingual/efeitos adversos , Imunoterapia Sublingual/métodos , Resultado do Tratamento , Adulto Jovem
10.
Artigo em Inglês | MEDLINE | ID: mdl-26979830

RESUMO

BACKGROUND: Filorexant (MK-6096) is an orexin receptor antagonist; here, we evaluate the efficacy of filorexant in the treatment of insomnia in adults. METHODS: A double-blind, placebo-controlled, randomized, two 4-week-period, adaptive crossover polysomnography study was conducted at 51 sites worldwide. Patients (18 to <65 years) with insomnia received 1 of 4 doses of oral filorexant (2.5, 5, 10, 20mg) once daily at bedtime during one period and matching placebo in the other period in 1 of 8 possible treatment sequences. Polysomnography was performed on night 1 and end of week 4 of each period. The primary endpoint was sleep efficiency at night 1 and end of week 4. Secondary endpoints included wakefulness after persistent sleep onset and latency to onset of persistent sleep. RESULTS: A total of 324 patients received study treatment, 315 received ≥1 dose of placebo, and 318 ≥1 dose of filorexant (2.5mg, n=79; 5mg, n=78; 10mg, n=80; 20mg, n=81). All filorexant doses (2.5/5/10/20mg) were significantly superior to placebo in improving sleep among patients with insomnia as measured by sleep efficiency and wakefulness after persistent sleep onset on night 1 and end of week 4. The 2 higher filorexant doses (10/20mg) were also significantly more effective than placebo in improving sleep onset as measured by latency to onset of persistent sleep at night 1 and end of week 4. Filorexant was generally well tolerated. CONCLUSIONS: Orexin receptor antagonism by filorexant significantly improved sleep efficiency in nonelderly patients with insomnia. Dose-related improvements in sleep onset and maintenance outcomes were also observed with filorexant.


Assuntos
Piperidinas/uso terapêutico , Pirimidinas/uso terapêutico , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Adolescente , Adulto , Estudos Cross-Over , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Antagonistas dos Receptores de Orexina/efeitos adversos , Antagonistas dos Receptores de Orexina/uso terapêutico , Piperidinas/efeitos adversos , Polissonografia , Pirimidinas/efeitos adversos , Resultado do Tratamento , Adulto Jovem
11.
Clin Infect Dis ; 61 Suppl 1: S18-24, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26224768

RESUMO

BACKGROUND: The hollow fiber system model of tuberculosis (HFS-TB) is designed to perform pharmacokinetics/pharmacodynamics (PK/PD) experiments, and hence the design of optimal doses and dose schedules for the treatment of tuberculosis. To determine if this model is useful for deriving PK/PD data relevant to clinical outcomes, we compared its quantitative output to that from clinical trials. METHODS: We performed a PubMed search to identify clinical studies performed with antituberculosis therapy in which PK/PD data and/or parameters were documented or a dose-scheduling study design was employed. The search period was from January 1943 to December 2012. All clinical studies were published prior to HFS-TB experiments. Bias minimization was done according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. Clinical publications were scored for quality of evidence, with 1 as the highest score (randomized controlled trials or meta-analyses of such studies), and 4 as the lowest score. RESULTS: We identified 17 studies that examined the same parameters as in 8 HFS-TB studies. Fifteen of 17 studies had a quality-of-evidence score of 1. The sterilizing and bactericidal effect rates for isoniazid, rifampin, pyrazinamide, and ethambutol were the same in the HFS-TB as in patients. Time to emergence of resistance for monotherapy was the same as in patients. The PK/PD indices associated with efficacy were the same in HFS-TB as in patients for all drugs examined. CONCLUSIONS: The HFS-TB model is highly accurate at identifying optimal drug exposures, doses, and dosing schedules for use in the clinic.


Assuntos
Antituberculosos/farmacologia , Antituberculosos/farmacocinética , Descoberta de Drogas , Mycobacterium tuberculosis/efeitos dos fármacos , Tuberculose/tratamento farmacológico , Antituberculosos/administração & dosagem , Antituberculosos/uso terapêutico , Ensaios Clínicos como Assunto , Relação Dose-Resposta a Droga , Farmacorresistência Bacteriana , Humanos , Testes de Sensibilidade Microbiana , Modelos Biológicos , Rifampina/administração & dosagem , Rifampina/farmacocinética , Rifampina/farmacologia , Rifampina/uso terapêutico , Fatores de Tempo
12.
Artif Organs ; 38(8): 691-701, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24749976

RESUMO

The intensity of ischemia-reperfusion injury of the donor organ during the preservation phase and after anastomosis is acknowledged as being a key factor for long-term graft outcome. We previously showed that the addition of 5 g/L of the natural oxygen carrier HEMO2 Life was beneficial for the cold static preservation of kidney grafts in both University of Wisconsin (UW) and histidine-tryptophan-ketoglutarate solutions. Herein, we refined these findings by evaluating HEMO2 Life at various dose levels in UW, both in vitro with endothelial cells and in vivo in a pig kidney autotransplantation preclinical model. We showed in vitro that cells were significantly better preserved with HEMO2 Life in a dose-dependent manner, with benefits in terms of survival, metabolic activity, and cellular integrity. In vivo, serum creatinine measurements at reperfusion confirmed the important benefits of HEMO2 Life treatment on function recovery at the dose levels of 1, 2, and 5 g/L. Likewise, histological analysis of kidney parenchyma biopsies from day 7 confirmed the superiority of HEMO2 Life-supplemented UW over UW alone, and there was no difference between the doses. Three months' follow-up confirmed the trend of the first 2 weeks, with creatinine and fibrosis levels similar to those in pretransplant kidneys.


Assuntos
Transplante de Rim/métodos , Rim/patologia , Soluções para Preservação de Órgãos/química , Preservação de Órgãos/métodos , Oxigênio/metabolismo , Animais
13.
Vaccine ; 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39025698

RESUMO

Despite current polysaccharide and conjugate vaccine use, pneumococcal diseases remain prevalent in older adults. VAX-24 is a 24-valent pneumococcal conjugate vaccine (PCV) containing eCRM, a proprietary carrier protein with non-native amino acids (para-azidomethyl-L-phenylalanine) that undergo site-specific conjugation to pneumococcal polysaccharides that have been activated with a small-molecule linker (dibenzocyclooctyne). Site-specific conjugation utilizing click chemistry enables consistent exposure of T-cell epitopes, reduction in carrier protein to pneumococcal polysaccharide ratio, and enhances manufacturing process consistency to improve PCVs by increasing serotype coverage while minimizing carrier suppression. Healthy adults aged 65 or older were randomized in a 1:1:1:1 ratio to receive a single injection of VAX-24 at 1 of 3 dose levels (1.1, 2.2, or a mixed dose of 2.2 or 4.4 mcg) or Prevnar 20® (PCV20) in a phase 2, blinded study. Primary outcome measures were solicited local and systemic events within 7 days post-vaccination, unsolicited adverse events (AEs) within 1 month, and serious AEs, medically attended AEs, or new onset of chronic disease within 6 months of vaccination. Serotype-specific opsonophagocytic activity (OPA) and immunoglobulin G (IgG) were measured pre-vaccination and at 1 month post-vaccination. Of 207 participants enrolled, 200 completed the trial. Safety profiles were comparable across the three VAX-24 doses and PCV20. Robust OPA and IgG immune responses were seen for all 24 serotypes. On average, immune responses to VAX-24 2.2 mcg dose were similar or higher compared to PCV20. In adults ≥ 65 years, VAX-24 had a safety profile similar to PCV20 through six months post-vaccination and induced robust OPA and IgG responses to all 24 serotypes, supporting prior data showing that site-specific conjugation allows for increased serotype coverage with similar or higher immune response vs other PCVs. The outcome of this phase 2 study further supports use of VAX-24 2.2 mcg dose in phase 3 trials. Clinicaltrials.gov: NCT05297578.

14.
Mol Ther Methods Clin Dev ; 32(1): 101201, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38374962

RESUMO

Mucopolysaccharidosis type II (MPS II) is an X-linked recessive lysosomal disease caused by iduronate-2-sulfatase (IDS) deficiency, leading to accumulation of glycosaminoglycans (GAGs) and the emergence of progressive disease. Enzyme replacement therapy is the only currently approved treatment, but it leaves neurological disease unaddressed. Cerebrospinal fluid (CSF)-directed administration of AAV9.CB7.hIDS (RGX-121) is an alternative treatment strategy, but it is unknown if this approach will affect both neurologic and systemic manifestations. We compared the effectiveness of intrathecal (i.t.) and intravenous (i.v.) routes of administration (ROAs) at a range of vector doses in a mouse model of MPS II. While lower doses were completely ineffective, a total dose of 1 × 109 gc resulted in appreciable IDS activity levels in plasma but not tissues. Total doses of 1 × 1010 and 1 × 1011 gc by either ROA resulted in supraphysiological plasma IDS activity, substantial IDS activity levels and GAG reduction in nearly all tissues, and normalized zygomatic arch diameter. In the brain, a dose of 1 × 1011 gc i.t. achieved the highest IDS activity levels and the greatest reduction in GAG content, and it prevented neurocognitive deficiency. We conclude that a dose of 1 × 1010 gc normalized metabolic and skeletal outcomes, while neurologic improvement required a dose of 1 × 1011 gc, thereby suggesting the prospect of a similar direct benefit in humans.

15.
Diabetes Obes Metab ; 15(8): 750-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23464532

RESUMO

AIM: To investigate the effect of glucokinase activator AZD1656 on glycated haemoglobin (HbA1c) as an add-on to metformin in patients with type 2 diabetes. METHODS: This randomized, double-blind, placebo-controlled study (NCT01020123) was conducted over 4 months with an optional 2-month extension. Patients (n = 458) with HbA1c 7.5-10% were randomized to AZD1656 20 mg (n = 40) or 40 mg (n = 52) fixed doses or 10-140 mg (n = 91) or 20-200 mg (n = 93) titrated doses, placebo (n = 88) or glipizide 5-20 mg titrated (n = 94). Patients (n = 72) with HbA1c >10 and ≤12% received open-label AZD1656 (20-200 mg titrated). Primary outcome was placebo-corrected change in HbA1c from baseline to 4 months of treatment. RESULTS: Significant reductions in HbA1c from baseline to 4 months were observed with blinded AZD1656 10-140 and 20-200 mg versus placebo [mean (95% CI) changes: -0.80 (-1.14; -0.46) and -0.81 (-1.14; -0.47) %, respectively), with similar reductions observed with glipizide. A higher percentage of patients on AZD1656 than on placebo achieved HbA1c ≤7.0 or ≤6.5 % after 4 months. Mean (s.d.) change in HbA1c for open-label AZD1656 (20-200 mg) was -2.8 (1.19) % after 4 months. AZD1656 was well tolerated, with less hypoglycaemia than glipizide. In the extension population, HbA1c was still reduced with AZD1656 versus placebo after 6 months, but the effect of AZD1656 on glucose control was not sustained over time. CONCLUSION: Addition of AZD1656 (individually titrated) to metformin gave significant improvements in glycaemic control up to 4 months, although efficacy diminished over time.


Assuntos
Azetidinas/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Reativadores Enzimáticos/uso terapêutico , Glucoquinase/metabolismo , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Pirazinas/uso terapêutico , Análise de Variância , Glicemia/metabolismo , Índice de Massa Corporal , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Método Duplo-Cego , Quimioterapia Combinada , Ativação Enzimática/efeitos dos fármacos , Europa (Continente)/epidemiologia , Jejum , Feminino , Glucoquinase/efeitos dos fármacos , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Resultado do Tratamento , Triglicerídeos/sangue
16.
Clin Ther ; 45(12): 1284-1288, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37872059

RESUMO

PURPOSE: This study evaluates the efficacy and tolerability of cyclosporine A cationic emulsion (CsA-CE) in patients ≥4 years of age with moderate-to-severe vernal keratoconjunctivitis (VKC). METHODS: This Phase II/III, multicenter, double-masked, dose-ranging study had 2 treatment periods: a 4-week, randomized, vehicle-controlled period in which patients received 0.05% CsA-CE, 0.1% CsA-CE, or vehicle eye drops 4 times daily (period 1) and a 3-month period in which patients received 0.05% CsA-CE or 0.1% CsA-CE 2 or 4 times daily (period 2). The primary efficacy end point was rating of subjective symptoms at day 28 in period 1 per the BenEzra scale. FINDINGS: All groups showed improvement in subjective VKC symptoms at day 28, without a statistically significant difference between 0.05% or 0.1% CsA-CE vs vehicle. Both CsA-CE doses produced statistically significant improvements in corneal fluorescein staining scores vs vehicle at day 28; improvements were evident as early as week 1 and continued through month 1. Progressive reduction in subjective itching was evident after week 1 and continued through month 1. Treatment for an additional 3 months further improved subjective symptoms and objective signs of VKC in both CsA-CE groups. Improvement was most notable with 0.1% CsA-CE in patients with severe keratitis. The safety and tolerability profile is favorable. IMPLICATIONS: Although treatment with 0.05% and 0.1% CsA-CE showed clinical efficacy in alleviating keratitis and itching as early as week 1, with sustained benefit through 1 month, the primary efficacy end point was not met. These findings informed the design of the Phase III trial of 0.1% CsA-CE (Vernal Keratoconjunctivitis Study). CLINICALTRIALS: gov identifier: NCT00328653.


Assuntos
Conjuntivite Alérgica , Ciclosporina , Ceratite , Humanos , Conjuntivite Alérgica/tratamento farmacológico , Ciclosporina/uso terapêutico , Método Duplo-Cego , Emulsões/uso terapêutico , Ceratite/tratamento farmacológico , Soluções Oftálmicas/uso terapêutico , Prurido , Resultado do Tratamento
17.
Int J Chron Obstruct Pulmon Dis ; 16: 1637-1646, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34113095

RESUMO

Background: Management of acute exacerbations of chronic obstructive pulmonary disease (COPD) is sometimes inadequate leading to either prolonged duration and/or an increased risk of recurrent exacerbations in the period following the initial event. Objective: To evaluate the safety and efficacy of inhaled nemiralisib, a phosphoinositide 3-kinase δ inhibitor, in patients experiencing an acute exacerbation of COPD. Patients and Methods: In this double-blind, placebo-controlled study, COPD patients (40-80 years, ≥10 pack-year smoking history, current moderate/severe acute exacerbation of COPD requiring standard-of-care treatment) were randomized to placebo or nemiralisib 12.5 µg, 50 µg, 100 µg, 250 µg, 500 µg, or 750 µg (ratio of 3:1:1:1:1:1:3; N=938) for 12 weeks with an exploratory 12-week follow-up period. The primary endpoint was change from baseline in post-bronchodilator FEV1 at week 12. Key secondary endpoints were rate of re-exacerbations, patient-reported outcomes (Exacerbations of Chronic Pulmonary Disease Tool, COPD Assessment Test, St George's Respiratory Questionnaire-COPD), plasma pharmacokinetics (PK) and safety/tolerability. Results: There was no difference in change from baseline FEV1 at week 12 between the nemiralisib and placebo treatment groups (posterior adjusted median difference, nemiralisib 750 µg and placebo: -0.004L (95% CrI: -0.051L to 0.042L)). Overall, there were also no differences between nemiralisib and placebo in secondary endpoints, including re-exacerbations. Plasma PK increased in a dose proportional manner. The most common adverse event for nemiralisib was post-inhalation cough which appeared to be dose-related. Conclusion: The addition of nemiralisib to standard-of-care treatment for 12 weeks did not improve lung function or re-exacerbations in patients with, and following an acute exacerbation of COPD. However, this study demonstrated that large clinical trials recruiting acutely exacerbating patients can successfully be conducted.


Assuntos
Fosfatidilinositol 3-Quinases , Doença Pulmonar Obstrutiva Crônica , Broncodilatadores/uso terapêutico , Método Duplo-Cego , Volume Expiratório Forçado , Humanos , Indazóis , Indóis , Oxazóis/farmacologia , Oxazóis/uso terapêutico , Fosfatidilinositol 3-Quinases/farmacologia , Fosfatidilinositol 3-Quinases/uso terapêutico , Piperazinas , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico
18.
Contemp Clin Trials ; 111: 106605, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34743987

RESUMO

The use of backfill in early phase dose-finding trials is a relatively recent practice. It consists of assigning patients to dose levels below the level where the study is at. The main reason for backfilling is to collect additional pharmacokinetic, pharmacodynamic and response data, in order to assess whether a plateau may exist on the dose-efficacy curve. This is a possibility in oncology with molecularly targeted agents or immunotherapy. Recommending for further study a dose level lower than the maximum tolerated dose could be supported in such situations. How to best allocate backfill patients to dose levels is not yet established. In this paper we propose to randomise backfill patients below the dose level where the study is at. A refinement of this would be to stop backfilling to lower dose levels when these show insufficient efficacy compared to higher levels, starting at dose level 1 and repeating this process sequentially. At study completion, data from all patients (both backfill patients and dose-finding patients) is used to estimate the dose-response curve. The fit from a change point model is compared to the fit of a monotonic model to identify a potential plateau. Using simulations, we show that this approach can identify the plateau on the dose-response curve when such a plateau exists, allowing the recommendation of a dose level lower than the maximum tolerated dose for future studies. This contribution provides a methodological framework for backfilling, from the perspective of both design and analysis in early phase oncology trials.


Assuntos
Neoplasias , Projetos de Pesquisa , Simulação por Computador , Relação Dose-Resposta a Droga , Humanos , Dose Máxima Tolerável , Oncologia , Neoplasias/tratamento farmacológico
19.
Brain Res ; 1727: 146587, 2020 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-31811838

RESUMO

Alzheimer's disease (AD) is a neurodegenerative disease mainly affecting old people. According to the "amyloid cascade hypothesis", the accumulation of Aß oligomers could lead to kinase activation and Tau phosphorylation. Activated kinases include c-Jun N-terminal kinase (JNK) and previous studies highlighted the beneficial effects of the JNK-specific inhibitor Brimapitide (10 mg/kg) in 5xFAD transgenic mice. Our aim was to evaluate the effects of decreasing doses of Brimapitide on cognition and neurodegeneration in early treated 5xFAD mice. Three month-old 5xFAD were intravenously treated for 6 months with either Brimapitide (3 mg/kg or 0.3 mg/kg) or Nacl. Cognition and amyloid burden, neuronal and synaptic impairments were evaluated. Low doses of Brimapitide (0.3 mg/kg) reduced neuronal degeneration and improved cognition in treated mice compared to non-treated mice. Amyloid burden and synaptic degeneration only decreased with the 3 mg/kg dose. This JNK inhibitor can afford neuroprotection but with a differential effect on amyloid deposition in 5xFAD mice. Brimapitide might partially prevent ongoing neurodegeneration in 5xFAD mice.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Hipocampo/efeitos dos fármacos , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Memória de Curto Prazo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/metabolismo , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Hipocampo/metabolismo , Hipocampo/patologia , Camundongos Transgênicos , Neurônios/metabolismo , Neurônios/patologia , Fármacos Neuroprotetores/administração & dosagem , Fragmentos de Peptídeos/metabolismo
20.
World Allergy Organ J ; 13(9): 100462, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32994855

RESUMO

BACKGROUND: Data on mepolizumab in patients with severe eosinophilic asthma (EA) and comorbidities are needed to assess whether randomized controlled trial results are applicable in the real world. OBJECTIVE: To evaluate real-life effectiveness and the presence/absence of predictors of treatment response in patients with one or more comorbidities (nasal polyps, allergic rhinitis, gastro-esophageal reflux disease, nonallergic rhinitis with eosinophilia syndrome, obesity, bronchiectasis) who received mepolizumab (MEPO) for the treatment of severe EA. METHODS: We performed a single-center retrospective study in patients with severe asthma and presence of comorbidities treated with mepolizumab at the respiratory outpatient clinic, Policlinico-Vittorio Emanuele, Catania, Italy. Health records of 31 severe asthmatic patients were retrieved and analyzed. Asthma control test (ACT) score, blood eosinophil count, forced expiratory volume in 1 s (FEV1), FEV1% of predicted and FEV1/FVC (Forced Vital Capacity) ratio, oral corticosteroid (OCS) dosage, and exacerbations were recorded at baseline (T0), after 3 (T1), 6 (T3), 9 (T6), and 12 months (T12). Clinical response was defined when 3 of these 4 criteria were fulfilled: i) 30% exacerbation decrease; ii) 80% blood eosinophilia reduction; iii) 3 point ACT increase; iv) FEV1 increase ≥200 mL. RESULTS: 83.87% of patients were classified as responsive to MEPO treatment. Substantial depletion of the blood eosinophils (>80%) was found in 87.1% of patients, FEV1 > 200 mL was seen in 54.84% of patients, a 3-point ACT improvement from baseline was recorded in 80.65% 25 of patients and a 30% reduction of exacerbations rates was seen in 96.77% of patients. Moreover, the majority 38.71% of patients met 3/4 parameters after 12 months. Neither the comorbidities nor other characteristics (sex, BMI, age, smoking) influenced treatment response. CONCLUSIONS: MEPO in patients with severe EA is effective regardless of the presence of comorbidities.

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