Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 35
Filtrar
1.
Cerebellum ; 22(4): 578-586, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35655106

RESUMO

Episodic ataxia type 1 (EA1) is a rare autosomal potassium channelopathy, due to mutations in KCNA1. Patients have childhood onset of intermittent attacks of ataxia, dizziness or imbalance. In order to quantify the natural history of EA1, its effect on quality of life and in preparation for future clinical trials, we set up an international multi-centre study of EA1. We recruited thirty-three participants with EA1: twenty-three completed 1-year follow-up and eighteen completed 2-year follow-up. There was very little accumulation of disability or impairment over the course of the 2 years of the study. The outcome measures of ataxia (SARA and functional rating of ataxia) and the activities of daily living scale were largely stable over time. Self-reported health-related quality of life (SF-36) scores were lower across all domains than controls, in keeping with a chronic condition. Physical subdomain scores appeared to deteriorate over time, which seems to be driven by the female participants in the study. This is an interesting finding and warrants further study. Attacks of EA1 reported by participants in real time via an interactive voice response system showed that symptoms were not stereotyped; however, attack duration and frequency was stable between individuals. This large prospective study is the first ever completed in subjects with EA1. We document the natural history of the disorder over 2 years. These data will enable the development of outcome measures for clinical trials of treatment.


Assuntos
Atividades Cotidianas , Qualidade de Vida , Humanos , Feminino , Criança , Estudos Prospectivos , Canal de Potássio Kv1.1/genética , Ataxia/diagnóstico
2.
N Engl J Med ; 381(7): 603-613, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31180194

RESUMO

BACKGROUND: Type 1 diabetes is a chronic autoimmune disease that leads to destruction of insulin-producing beta cells and dependence on exogenous insulin for survival. Some interventions have delayed the loss of insulin production in patients with type 1 diabetes, but interventions that might affect clinical progression before diagnosis are needed. METHODS: We conducted a phase 2, randomized, placebo-controlled, double-blind trial of teplizumab (an Fc receptor-nonbinding anti-CD3 monoclonal antibody) involving relatives of patients with type 1 diabetes who did not have diabetes but were at high risk for development of clinical disease. Patients were randomly assigned to a single 14-day course of teplizumab or placebo, and follow-up for progression to clinical type 1 diabetes was performed with the use of oral glucose-tolerance tests at 6-month intervals. RESULTS: A total of 76 participants (55 [72%] of whom were ≤18 years of age) underwent randomization - 44 to the teplizumab group and 32 to the placebo group. The median time to the diagnosis of type 1 diabetes was 48.4 months in the teplizumab group and 24.4 months in the placebo group; the disease was diagnosed in 19 (43%) of the participants who received teplizumab and in 23 (72%) of those who received placebo. The hazard ratio for the diagnosis of type 1 diabetes (teplizumab vs. placebo) was 0.41 (95% confidence interval, 0.22 to 0.78; P = 0.006 by adjusted Cox proportional-hazards model). The annualized rates of diagnosis of diabetes were 14.9% per year in the teplizumab group and 35.9% per year in the placebo group. There were expected adverse events of rash and transient lymphopenia. KLRG1+TIGIT+CD8+ T cells were more common in the teplizumab group than in the placebo group. Among the participants who were HLA-DR3-negative, HLA-DR4-positive, or anti-zinc transporter 8 antibody-negative, fewer participants in the teplizumab group than in the placebo group had diabetes diagnosed. CONCLUSIONS: Teplizumab delayed progression to clinical type 1 diabetes in high-risk participants. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT01030861.).


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Complexo CD3/antagonistas & inibidores , Diabetes Mellitus Tipo 1/prevenção & controle , Adolescente , Adulto , Anticorpos Monoclonais Humanizados/efeitos adversos , Criança , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Progressão da Doença , Método Duplo-Cego , Exantema/induzido quimicamente , Feminino , Teste de Tolerância a Glucose , Antígeno HLA-DR3 , Antígeno HLA-DR4 , Humanos , Contagem de Linfócitos , Linfopenia/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Linfócitos T/imunologia , Adulto Jovem
3.
Lancet ; 394(10205): 1286-1296, 2019 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-31533907

RESUMO

Over several decades, studies have described the progression of autoimmune diabetes, from the first appearance of autoantibodies until, and after, the diagnosis of clinical disease with hyperglycaemia and insulin dependence. Despite the improved management of type 1 diabetes with exogenous insulin, most patients do not meet clinical glycaemic goals, and diabetes remains an important medical problem that affects children and adults. Clinical and preclinical studies have suggested strategies to prevent the diagnosis of type 1 diabetes in people at risk, but the outcomes of previous clinical trials have not met their primary endpoints of disease prevention or delay. The results from the TN-10 teplizumab prevention trial show that the diagnosis of type 1 diabetes can be delayed by treatment with a FcR non-binding monoclonal antibody to CD3 in people at high risk for disease. This Series paper discusses how this clinical achievement raises new questions about for whom, and when, immunological strategies might be developed to prevent type 1 diabetes, and how to achieve this goal.


Assuntos
Diabetes Mellitus Tipo 1/prevenção & controle , Anticorpos Monoclonais Humanizados/uso terapêutico , Diabetes Mellitus Tipo 1/etiologia , Diabetes Mellitus Tipo 1/imunologia , Humanos
6.
Diabetes Metab Res Rev ; 32(8): 827-834, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26991448

RESUMO

BACKGROUND: The area under the curve C-peptide following a 2-h mixed meal tolerance test from 498 individuals enrolled on five prior TrialNet studies of recent onset type 1 diabetes from baseline to 12 months after enrolment were modelled to produce estimates of its rate of loss and variance. RESULTS: Age at diagnosis and baseline C-peptide were found to be significant predictors, and adjusting for these in an ANCOVA resulted in estimates with lower variance. CONCLUSIONS: Using these results as planning parameters for new studies results in a nearly 50% reduction in the target sample size. The modelling also produces an expected C-peptide that can be used in observed versus expected calculations to estimate the presumption of benefit in ongoing trials. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Biomarcadores/sangue , Diabetes Mellitus Tipo 1/fisiopatologia , Modelos Estatísticos , Adolescente , Adulto , Idade de Início , Área Sob a Curva , Peptídeo C/sangue , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Tamanho da Amostra , Adulto Jovem
7.
Brain ; 137(Pt 4): 1009-18, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24578548

RESUMO

Episodic ataxia type 1 is considered a rare neuronal ion channel disorder characterized by brief attacks of unsteadiness and dizziness with persistent myokymia. To characterize the natural history, develop outcome measures for future clinical trials, and correlate genotype with phenotype, we undertook an international, prospective, cross-sectional study. Thirty-nine individuals (51% male) were enrolled: median age 37 years (range 15-65 years). We identified 10 different pathogenic point mutations in KCNA1 that accounted for the genetic basis of 85% of the cohort. Participants with KCNA1 mutations were more likely to have a positive family history. Analysis of the total cohort showed that the first episode of ataxia occurred before age 20 in all but one patient, with an average age of onset of 7.9 years. Physical exertion, emotional stress and environmental temperature were the most common triggers for attacks. Attack frequency ranged from daily to monthly, even with the same KCNA1 genotype. Average attack duration was in the order of minutes. Ten participants (26%) developed permanent cerebellar signs, which were related to disease duration. The average Scale for the Assessment and Rating of Ataxia score (SARA, a standardized measure of cerebellar dysfunction on clinical examination, scores range from 0-40) was an average of 3.15 for all participants (range 0-14), but was only 2 in those with isolated episodic ataxia compared with 7.7 in those with progressive cerebellar ataxia in addition to episodic ataxia. Thirty-seven participants completed the SF-36, a quality of life survey; all eight domain norm-based average scores (mean=50) were below normal with mental health being the lowest (41.3) in those with mutation positive episodic ataxia type 1. Scores on SF-36 correlated negatively with attack frequency. Of the 39 participants in the study, 33 harboured mutations in KCNA1 whereas the remaining six had no mutation identified. Episodic ataxia type 1 phenocopies have not been described previously and we report their clinical features, which appear to be different to those with a KCNA1 mutation. This large prospective study of both genetically confirmed episodic ataxia type 1 and episodic ataxia type 1 phenocopies provides detailed baseline characteristics of these disorders and their impact on participants. We found that attacks had a significant effect on quality of life. Unlike previous studies, we found that a significant number of individuals with genetically confirmed episodic ataxia type 1 (21%) had accumulated persistent cerebellar symptoms and signs. These data will enable the development of outcome measures for clinical trials of treatment.


Assuntos
Ataxia/genética , Ataxia/psicologia , Estudos de Associação Genética , Mioquimia/genética , Mioquimia/psicologia , Qualidade de Vida , Adolescente , Adulto , Idade de Início , Idoso , Ataxia/complicações , Estudos Transversais , Feminino , Humanos , Canal de Potássio Kv1.1/genética , Masculino , Pessoa de Meia-Idade , Mioquimia/complicações , Mutação Puntual , Adulto Jovem
8.
Diabetes Care ; 47(6): 1048-1055, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38621411

RESUMO

OBJECTIVE: Mixed-meal tolerance test-stimulated area under the curve (AUC) C-peptide at 12-24 months represents the primary end point for nearly all intervention trials seeking to preserve ß-cell function in recent-onset type 1 diabetes. We hypothesized that participant benefit might be detected earlier and predict outcomes at 12 months posttherapy. Such findings would support shorter trials to establish initial efficacy. RESEARCH DESIGN AND METHODS: We examined data from six Type 1 Diabetes TrialNet immunotherapy randomized controlled trials in a post hoc analysis and included additional stimulated metabolic indices beyond C-peptide AUC. We partitioned the analysis into successful and unsuccessful trials and analyzed the data both in the aggregate as well as individually for each trial. RESULTS: Among trials meeting their primary end point, we identified a treatment effect at 3 and 6 months when using C-peptide AUC (P = 0.030 and P < 0.001, respectively) as a dynamic measure (i.e., change from baseline). Importantly, no such difference was seen in the unsuccessful trials. The use of C-peptide AUC as a 6-month dynamic measure not only detected treatment efficacy but also suggested long-term C-peptide preservation (R2 for 12-month C-peptide AUC adjusted for age and baseline value was 0.80, P < 0.001), and this finding supported the concept of smaller trial sizes down to 54 participants. CONCLUSIONS: Early dynamic measures can identify a treatment effect among successful immune therapies in type 1 diabetes trials with good long-term prediction and practical sample size over a 6-month period. While external validation of these findings is required, strong rationale and data exist in support of shortening early-phase clinical trials.


Assuntos
Peptídeo C , Diabetes Mellitus Tipo 1 , Imunoterapia , Diabetes Mellitus Tipo 1/terapia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 1/imunologia , Humanos , Peptídeo C/sangue , Peptídeo C/metabolismo , Imunoterapia/métodos , Feminino , Masculino , Adolescente , Resultado do Tratamento , Ensaios Clínicos Controlados Aleatórios como Assunto , Criança , Adulto , Área Sob a Curva
9.
J Clin Oncol ; 41(25): 4077-4083, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37643542

RESUMO

Purpose: In randomized trials the combination of cisplatin and paclitaxel was superior to cisplatin and cyclophosphamide in advanced-stage epithelial ovarian cancer. Although in nonrandomized trials, carboplatin and paclitaxel was a less toxic and highly active combination regimen, there remained concern regarding its efficacy in patients with small-volume, resected, stage III disease. Thus, we conducted a noninferiority trial of cisplatin and paclitaxel versus carboplatin and paclitaxel in this population.Patients and Methods: Patients with advanced ovarian cancer and no residual mass greater than 1.0 cm after surgery were randomly assigned to receive cisplatin 75 mg/m2 plus a 24-hour infusion of paclitaxel 135 mg/m2 (arm I), or carboplatin area under the curve 7.5 intravenously plus paclitaxel 175 mg/m2 over 3 hours (arm II).Results: Seven hundred ninety-two eligible patients were enrolled onto the study. Prognostic factors were similar in the two treatment groups. Gastrointestinal, renal, and metabolic toxicity, as well as grade 4 leukopenia, were significantly more frequent in arm I. Grade 2 or greater thrombocytopenia was more common in arm II. Neurologic toxicity was similar in both regimens. Median progression-free survival and overall survival were 19.4 and 48.7 months, respectively, for arm I compared with 20.7 and 57.4 months, respectively, for arm II. The relative risk (RR) of progression for the carboplatin plus paclitaxel group was 0.88 (95% confidence interval [CI], 0.75 to 1.03) and the RR of death was 0.84 (95% CI, 0.70 to 1.02).Conclusion: In patients with advanced ovarian cancer, a chemotherapy regimen consisting of carboplatin plus paclitaxel results in less toxicity, is easier to administer, and is not inferior, when compared with cisplatin plus paclitaxel.

10.
Diabetes Care ; 46(5): 1005-1013, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36920087

RESUMO

OBJECTIVE: Previous studies showed that inhibiting lymphocyte costimulation reduces declining ß-cell function in individuals newly diagnosed with type 1 diabetes. We tested whether abatacept would delay or prevent progression of type 1 diabetes from normal glucose tolerance (NGT) to abnormal glucose tolerance (AGT) or to diabetes and the effects of treatment on immune and metabolic responses. RESEARCH DESIGN AND METHODS: We conducted a phase 2, randomized, placebo-controlled, double-masked trial of abatacept in antibody-positive participants with NGT who received monthly abatacept/placebo infusions for 12 months. The end point was AGT or diabetes, assessed by oral glucose tolerance tests. RESULTS: A total of 101 participants received abatacept and 111 placebo. Of these, 81 (35 abatacept and 46 placebo) met the end point of AGT or type 1 diabetes diagnosis (hazard ratio 0.702; 95% CI 0.452, 1.09; P = 0.11) The C-peptide responses to oral glucose tolerance tests were higher in the abatacept arm (P < 0.03). Abatacept reduced the frequency of inducible T-cell costimulatory (ICOS)+ PD1+ T-follicular helper (Tfh) cells during treatment (P < 0.0001), increased naive CD4+ T cells, and also reduced the frequency of CD4+ regulatory T cells (Tregs) from the baseline (P = 0.0067). Twelve months after treatment, the frequency of ICOS+ Tfh, naive CD4+ T cells, and Tregs returned to baseline. CONCLUSIONS: Although abatacept treatment for 1 year did not significantly delay progression to glucose intolerance in at-risk individuals, it impacted immune cell subsets and preserved insulin secretion, suggesting that costimulation blockade may modify progression of type 1 diabetes.


Assuntos
Diabetes Mellitus Tipo 1 , Humanos , Abatacepte/uso terapêutico , Abatacepte/farmacologia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Imunossupressores , Linfócitos T Reguladores , Glucose/uso terapêutico
11.
Muscle Nerve ; 46(4): 482-9, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22987687

RESUMO

INTRODUCTION: Non-dystrophic myotonia (NDM) is characterized by myotonia without muscle wasting. A standardized quantitative myotonia assessment (QMA) is important for clinical trials. METHODS: Myotonia was assessed in 91 individuals enrolled in a natural history study using a commercially available computerized handgrip myometer and automated software. Average peak force and 90% to 5% relaxation times were compared with historical normal controls studied with identical methods. RESULTS: Thirty subjects had chloride channel mutations, 31 had sodium channel mutations, 6 had DM2 mutations, and 24 had no identified mutation. Chloride channel mutations were associated with prolonged first handgrip relaxation times and warm-up on subsequent handgrips. Sodium channel mutations were associated with prolonged first handgrip relaxation times and paradoxical myotonia or warm-up, depending on underlying mutations. DM2 subjects had normal relaxation times but decreased peak force. Sample size estimates are provided for clinical trial planning. CONCLUSION: QMA is an automated, non-invasive technique for evaluating myotonia in NDM.


Assuntos
Teste de Esforço/métodos , Força da Mão/fisiologia , Debilidade Muscular/diagnóstico , Debilidade Muscular/fisiopatologia , Miotonia/diagnóstico , Miotonia/fisiopatologia , Adulto , Idoso , Canais de Cloreto/genética , Diagnóstico por Computador/métodos , Diagnóstico por Computador/normas , Teste de Esforço/normas , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Debilidade Muscular/genética , Mutação , Miotonia/genética , Canais de Sódio/genética , Adulto Jovem
12.
JAMA ; 308(13): 1357-65, 2012 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-23032552

RESUMO

CONTEXT: Nondystrophic myotonias (NDMs) are rare diseases caused by mutations in skeletal muscle ion channels. Patients experience delayed muscle relaxation causing functionally limiting stiffness and pain. Mexiletine-induced sodium channel blockade reduced myotonia in small studies; however, as is common in rare diseases, larger studies of safety and efficacy have not previously been considered feasible. OBJECTIVE: To determine the effects of mexiletine for symptoms and signs of myotonia in patients with NDMs. DESIGN, SETTING, AND PARTICIPANTS: A randomized, double-blind, placebo-controlled 2-period crossover study at 7 neuromuscular referral centers in 4 countries of 59 patients with NDMs conducted between December 23, 2008, and March 30, 2011, as part of the National Institutes of Health-funded Rare Disease Clinical Research Network. INTERVENTION: Oral 200-mg mexiletine or placebo capsules 3 times daily for 4 weeks, followed by the opposite intervention for 4 weeks, with 1-week washout in between. MAIN OUTCOME MEASURES: Patient-reported severity score of stiffness recorded on an interactive voice response (IVR) diary (scale of 1 = minimal to 9 = worst ever experienced). Secondary end points included IVR-reported changes in pain, weakness, and tiredness; clinical myotonia assessment; quantitative measure of handgrip myotonia; and Individualized Neuromuscular Quality of Life summary quality of life score (INQOL-QOL, percentage of maximal detrimental impact). RESULTS: Mexiletine significantly improved patient-reported severity score stiffness on the IVR diary. Because of a statistically significant interaction between treatment and period for this outcome, primary end point is presented by period (period 1 means were 2.53 for mexiletine and 4.21 for placebo; difference, -1.68; 95% CI, -2.66 to -0.706; P < .001; period 2 means were 1.60 for mexiletine and 5.27 for placebo; difference, -3.68; 95% CI, -3.85 to -0.139; P = .04). Mexiletine improved the INQOL-QOL score (mexiletine, 14.0 vs placebo, 16.7; difference, -2.69; 95% CI, -4.07 to -1.30; P < .001) and decreased handgrip myotonia on clinical examination (mexiletine, 0.164 seconds vs placebo, 0.494 seconds; difference, -0.330; 95% CI, -0.633 to -0.142; P < .001). The most common adverse effect was gastrointestinal (9 mexiletine and 1 placebo). Two participants experienced transient cardiac effects that did not require stopping the study (1 in each group). One serious adverse event was determined to be not study related. CONCLUSION: In this preliminary study of patients with NDMs, the use of mexiletine compared with placebo resulted in improved patient-reported stiffness over 4 weeks of treatment, despite some concern about the maintenance of blinding. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00832000.


Assuntos
Antiarrítmicos/uso terapêutico , Mexiletina/uso terapêutico , Miotonia/tratamento farmacológico , Administração Oral , Adolescente , Adulto , Idoso , Antiarrítmicos/efeitos adversos , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Mexiletina/efeitos adversos , Pessoa de Meia-Idade , Músculo Esquelético/fisiopatologia , Dor/tratamento farmacológico , Dor/etiologia , Qualidade de Vida , Índice de Gravidade de Doença , Canais de Sódio/efeitos dos fármacos , Adulto Jovem
13.
J Clin Endocrinol Metab ; 107(10): 2784-2792, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-35880956

RESUMO

CONTEXT: HbA1c from ≥ 5.7% to < 6.5% (39-46 mmol/mol) indicates prediabetes according to American Diabetes Association guidelines, yet its identification of prediabetes specific for type 1 diabetes has not been assessed. A composite glucose and C-peptide measure, Index60, identifies individuals at high risk for type 1 diabetes. OBJECTIVE: We compared Index60 and HbA1c thresholds as markers for type 1 diabetes risk. METHODS: TrialNet Pathway to Prevention study participants with ≥ 2 autoantibodies (GADA, IAA, IA-2A, or ZnT8A) who had oral glucose tolerance tests and HbA1c measurements underwent 1) predictive time-dependent modeling of type 1 diabetes risk (n = 2776); and 2) baseline comparisons between high-risk mutually exclusive groups: Index60 ≥ 2.04 (n = 268) vs HbA1c ≥ 5.7% (n = 268). The Index60 ≥ 2.04 threshold was commensurate in ordinal ranking with the standard prediabetes threshold of HbA1c ≥ 5.7%. RESULTS: In mutually exclusive groups, individuals exceeding Index60 ≥ 2.04 had a higher cumulative incidence of type 1 diabetes than those exceeding HbA1c ≥ 5.7% (P < 0.0001). Appreciably more individuals with Index60 ≥ 2.04 were at stage 2, and among those at stage 2, the cumulative incidence was higher for those with Index60 ≥ 2.04 (P = 0.02). Those with Index60 ≥ 2.04 were younger, with lower BMI, greater autoantibody number, and lower C-peptide than those with HbA1c ≥ 5.7% (P < 0.0001 for all comparisons). CONCLUSION: Individuals with Index60 ≥ 2.04 are at greater risk for type 1 diabetes with features more characteristic of the disorder than those with HbA1c ≥ 5.7%. Index60 ≥ 2.04 is superior to the standard HbA1c ≥ 5.7% threshold for identifying prediabetes in autoantibody-positive individuals. These findings appear to justify using Index60 ≥ 2.04 as a prediabetes criterion in this population.


Assuntos
Diabetes Mellitus Tipo 1 , Estado Pré-Diabético , Autoanticorpos , Glicemia/metabolismo , Peptídeo C , Diabetes Mellitus Tipo 1/diagnóstico , Diabetes Mellitus Tipo 1/epidemiologia , Diabetes Mellitus Tipo 1/metabolismo , Hemoglobinas Glicadas/análise , Humanos , Estado Pré-Diabético/diagnóstico , Estado Pré-Diabético/epidemiologia
14.
Sci Transl Med ; 13(583)2021 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-33658358

RESUMO

We analyzed the effects of a single 14-day course of teplizumab treatment on metabolic function and immune cells among participants in a previously reported randomized controlled trial of nondiabetic relatives at high risk for type 1 diabetes (T1D). In an extended follow-up (923-day median) of a previous report of teplizumab treatment, we found that the median times to diagnosis were 59.6 and 27.1 months for teplizumab- and placebo-treated participants, respectively (HR = 0.457, P = 0.01). Fifty percent of teplizumab-treated but only 22% of the placebo-treated remained diabetes-free. Glucose tolerance, C-peptide area under the curve (AUC), and insulin secretory rates were calculated, and relationships to T cell subsets and function were analyzed. Teplizumab treatment improved beta cell function, reflected by average on-study C-peptide AUC (1.94 versus 1.72 pmol/ml; P = 0.006). Drug treatment reversed a decline in insulin secretion before enrollment, followed by stabilization of the declining C-peptide AUC seen with placebo treatment. Proinsulin:C-peptide ratios after drug treatment were similar between the treatment groups. The changes in C-peptide with teplizumab treatment were associated with increases in partially exhausted memory KLRG1+TIGIT+CD8+ T cells (r = 0.44, P = 0.014) that showed reduced secretion of IFNγ and TNFα. A single course of teplizumab had lasting effects on delay of T1D diagnosis and improved beta cell function in high-risk individuals. Changes in CD8+ T cell subsets indicated that partially exhausted effector cells were associated with clinical response. Thus, this trial showed improvement in metabolic responses and delay of diabetes with immune therapy.


Assuntos
Linfócitos T CD8-Positivos , Diabetes Mellitus Tipo 1 , Anticorpos Monoclonais Humanizados , Peptídeo C , Diabetes Mellitus Tipo 1/tratamento farmacológico , Humanos , Insulina
15.
Lancet Diabetes Endocrinol ; 9(8): 502-514, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34214479

RESUMO

BACKGROUND: Type 1 diabetes results from autoimmune-mediated destruction of ß cells. The tyrosine kinase inhibitor imatinib might affect relevant immunological and metabolic pathways, and preclinical studies show that it reverses and prevents diabetes. Our aim was to evaluate the safety and efficacy of imatinib in preserving ß-cell function in patients with recent-onset type 1 diabetes. METHODS: We did a multicentre, randomised, double-blind, placebo-controlled, phase 2 trial. Patients with recent-onset type 1 diabetes (<100 days from diagnosis), aged 18-45 years, positive for at least one type of diabetes-associated autoantibody, and with a peak stimulated C-peptide of greater than 0·2 nmol L-1 on a mixed meal tolerance test (MMTT) were enrolled from nine medical centres in the USA (n=8) and Australia (n=1). Participants were randomly assigned (2:1) to receive either 400 mg imatinib mesylate (4 × 100 mg film-coated tablets per day) or matching placebo for 26 weeks via a computer-generated blocked randomisation scheme stratified by centre. Treatment assignments were masked for all participants and study personnel except pharmacists at each clinical site. The primary endpoint was the difference in the area under the curve (AUC) mean for C-peptide response in the first 2 h of an MMTT at 12 months in the imatinib group versus the placebo group, with use of an ANCOVA model adjusting for sex, baseline age, and baseline C-peptide, with further observation up to 24 months. The primary analysis was by intention to treat (ITT). Safety was assessed in all randomly assigned participants. This study is registered with ClinicalTrials.gov, NCT01781975 (completed). FINDINGS: Patients were screened and enrolled between Feb 12, 2014, and May 19, 2016. 45 patients were assigned to receive imatinib and 22 to receive placebo. After withdrawals, 43 participants in the imatinib group and 21 in the placebo group were included in the primary ITT analysis at 12 months. The study met its primary endpoint: the adjusted mean difference in 2-h C-peptide AUC at 12 months for imatinib versus placebo treatment was 0·095 (90% CI -0·003 to 0·191; p=0·048, one-tailed test). This effect was not sustained out to 24 months. During the 24-month follow-up, 32 (71%) of 45 participants who received imatinib had a grade 2 severity or worse adverse event, compared with 13 (59%) of 22 participants who received placebo. The most common adverse events (grade 2 severity or worse) that differed between the groups were gastrointestinal issues (six [13%] participants in the imatinib group, primarily nausea, and none in the placebo group) and additional laboratory investigations (ten [22%] participants in the imatinib group and two [9%] in the placebo group). Per the trial protocol, 17 (38%) participants in the imatinib group required a temporary modification in drug dosing and six (13%) permanently discontinued imatinib due to adverse events; five (23%) participants in the placebo group had temporary modifications in dosing and none had a permanent discontinuation due to adverse events. INTERPRETATION: A 26-week course of imatinib preserved ß-cell function at 12 months in adults with recent-onset type 1 diabetes. Imatinib might offer a novel means to alter the course of type 1 diabetes. Future considerations are defining ideal dose and duration of therapy, safety and efficacy in children, combination use with a complimentary drug, and ability of imatinib to delay or prevent progression to diabetes in an at-risk population; however, careful monitoring for possible toxicities is required. FUNDING: Juvenile Research Diabetes Foundation.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Mesilato de Imatinib/uso terapêutico , Inibidores de Proteínas Quinases/uso terapêutico , Adolescente , Adulto , Biomarcadores/análise , Glicemia/análise , Diabetes Mellitus Tipo 1/patologia , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Adulto Jovem
16.
Endocrinol Diabetes Metab ; 3(3): e00143, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32704564

RESUMO

INTRODUCTION: This paper develops a methodology and defines a measure that can be used to separate subjects that received an experimental therapy into those that benefitted from those that did not in recent-onset type 1 diabetes. Benefit means a slowing (or arresting) the decline in beta-cell function over time. The measure can be applied to comparing treatment arms from a clinical trial or to response at the individual level. METHODS: An analysis of covariance model was fitted to the 12-month area under the curve C-peptide following a 2-hour mixed meal tolerance test from 492 individuals enrolled on five TrialNet studies of recent-onset type 1 diabetes. Significant predictors in the model were age and C-peptide at study entry. The observed minus the model-based expected C-peptide value (quantitative response, QR) is defined to reflect the effect of the therapy. RESULTS: A comparison of the primary hypothesis test for each study included and a t test of the QR value by treatment group were comparable. The results were also confirmed for a new TrialNet study, independent of the set of studies used to derive the model. With our proposed analytical method and using QR as the end-point, we conducted simulation studies, to estimate statistical power in detecting a biomarker that expresses differential treatment effect. The QR in its continuous form provided the greatest statistical power when compared to several ways of defining responder/non-responder using various QR thresholds. CONCLUSIONS: This paper illustrates the use of the QR, as a measure of the magnitude of treatment effect at the aggregate and subject-level. We show that the QR distribution by treatment group provides a better sense of the treatment effect than simply giving the mean estimates. Using the QR in its continuous form is shown to have higher statistical power in comparison with dichotomized categorization.

17.
Diabetes Care ; 43(8): 1836-1842, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32457058

RESUMO

OBJECTIVE: Insulin secretion declines rapidly after diagnosis of type 1 diabetes, followed by a slower rate of change. Previous studies have demonstrated that the C-peptide decline begins before the clinical diagnosis. Changes in insulin secretion in the same individuals studied from preclinical stages through and after clinical diagnosis have not been previously reported. RESEARCH DESIGN AND METHODS: Antibody-positive relatives undergo sequential oral glucose tolerance testing (OGTT) as part of TrialNet's Pathway to Prevention study and continue both OGTT and mixed-meal tolerance testing (MMTT) as part of the Long-term Investigational Follow-up in TrialNet study if they develop type 1 diabetes. We analyzed glucose and C-peptide data obtained from 80 TrialNet subjects who had OGTT before and after clinical diagnosis. Separately, we compared C-peptide response to OGTT and MMTT in 127 participants after diagnosis. RESULTS: C-peptide did not change significantly until 6 months before the clinical diagnosis of type 1 diabetes and continued to decline postdiagnosis, and the rates of decline for the first 6 months postdiagnosis were similar to the 6 months prediagnosis. There were no significant differences in MMTT and OGTT C-peptide responses in paired tests postdiagnosis. CONCLUSIONS: This is the first analysis of C-peptide levels in longitudinally monitored patients with type 1 diabetes studied from before diagnosis and continuing to the postdiagnosis period. These data highlight the discordant timing between accelerated ß-cell dysfunction and the current glucose thresholds for clinical diagnosis. To preserve ß-cell function, disease-modifying therapy should start at or before the acute decline in C-peptide.


Assuntos
Peptídeo C/sangue , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/diagnóstico , Adolescente , Adulto , Glicemia/metabolismo , Peptídeo C/análise , Criança , Pré-Escolar , Estudos de Coortes , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/patologia , Técnicas de Diagnóstico Endócrino , Progressão da Doença , Feminino , Seguimentos , Teste de Tolerância a Glucose , Humanos , Secreção de Insulina/fisiologia , Estudos Longitudinais , Masculino , Refeições , Pessoa de Meia-Idade , Monitorização Fisiológica , Adulto Jovem
18.
Diabetes Technol Ther ; 22(12): 948-953, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32833543

RESUMO

Several immunotherapies have demonstrated endogenous insulin preservation in recent-onset type 1 diabetes (T1D). We considered the primary results of rituximab, abatacept, teplizumab, alefacept, high-dose antithymocyte globulin (ATG), low-dose ATG, and low-dose ATG ± granulocyte-colony-stimulating factor trials in an attempt to rank the effectiveness of the agents studied. C-peptide 2-h area under the curve means were modeled using analysis of covariance. The experimental treatment group effect for each study, compared with its internal control, was estimated after adjusting for baseline C-peptide and age. Percentage increase in C-peptide over placebo and the absolute difference within study were calculated to compare and contrast effect size among interventions. Low-dose ATG (55% and 103%) and teplizumab (48% and 63%) ranked highest in C-peptide preservation at 1 and 2 years, respectively. Low-dose ATG and teplizumab show the greatest impact on C-peptide preservation among recent new-onset T1D studies; these should be further explored as core immunotherapies in the T1D prevention setting.


Assuntos
Diabetes Mellitus Tipo 1 , Imunoterapia , Células Secretoras de Insulina , Abatacepte , Alefacept , Anticorpos Monoclonais Humanizados , Soro Antilinfocitário , Peptídeo C , Ensaios Clínicos como Assunto , Diabetes Mellitus Tipo 1/tratamento farmacológico , Fator Estimulador de Colônias de Granulócitos , Humanos , Insulina/uso terapêutico , Rituximab
19.
Diabetes ; 68(6): 1267-1276, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30967424

RESUMO

A three-arm, randomized, double-masked, placebo-controlled phase 2b trial performed by the Type 1 Diabetes TrialNet Study Group previously demonstrated that low-dose anti-thymocyte globulin (ATG) (2.5 mg/kg) preserved ß-cell function and reduced HbA1c for 1 year in new-onset type 1 diabetes. Subjects (N = 89) were randomized to 1) ATG and pegylated granulocyte colony-stimulating factor (GCSF), 2) ATG alone, or 3) placebo. Herein, we report 2-year area under the curve (AUC) C-peptide and HbA1c, prespecified secondary end points, and potential immunologic correlates. The 2-year mean mixed-meal tolerance test-stimulated AUC C-peptide, analyzed by ANCOVA adjusting for baseline C-peptide, age, and sex (n = 82) with significance defined as one-sided P < 0.025, was significantly higher in subjects treated with ATG versus placebo (P = 0.00005) but not ATG/GCSF versus placebo (P = 0.032). HbA1c was significantly reduced at 2 years in subjects treated with ATG (P = 0.011) and ATG/GCSF (P = 0.022) versus placebo. Flow cytometry analyses demonstrated reduced circulating CD4:CD8 ratio, increased regulatory T-cell:conventional CD4 T-cell ratios, and increased PD-1+CD4+ T cells following low-dose ATG and ATG/GCSF. Low-dose ATG partially preserved ß-cell function and reduced HbA1c 2 years after therapy in new-onset type 1 diabetes. Future studies should determine whether low-dose ATG might prevent or delay the onset of type 1 diabetes.


Assuntos
Soro Antilinfocitário/uso terapêutico , Diabetes Mellitus Tipo 1/tratamento farmacológico , Fatores Imunológicos/uso terapêutico , Adolescente , Adulto , Peptídeo C/metabolismo , Relação CD4-CD8 , Criança , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/metabolismo , Método Duplo-Cego , Feminino , Citometria de Fluxo , Hemoglobinas Glicadas/metabolismo , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Humanos , Masculino , Linfócitos T Reguladores/imunologia , Adulto Jovem
20.
Int J Cancer ; 123(6): 1376-84, 2008 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-18567002

RESUMO

We have previously shown that ovarian tumors express prostate-derived Ets transcription factor (PDEF). However, the precise role of PDEF in the prognosis of ovarian cancer is unknown. In our study, we report for the first time that expression of PDEF in tumor lesions of patients with ovarian cancer is associated with favorable prognosis. Evaluation of samples from 40 patients with ovarian cancer showed that early stage (IA) and borderline (IIB, III) ovarian tumors expressed higher levels of PDEF mRNA and protein and lower levels of survivin compared to late stage ovarian tumors (IIIC and IV, p < 0.05). Normal ovarian tissues expressed the highest levels of PDEF mRNA and protein when compared to tumor tissues (p < 0.05). A Log-Rank test showed that overall survival of patients with PDEF-positive and survivin-negative ovarian tumors was significantly longer than those with PDEF-negative and survivin-positive tumors (p < 0.01). Forced expression of PDEF in PDEF-negative ovarian tumor cells inhibited tumor cell growth, induced apoptosis, downregulated survivin expression and its promoter activity. Furthermore, treatment of ovarian cancer cells with vitamin D or a selenium compound resulted in re-expression of PDEF, downregulation of survivin, induction of apoptosis and inhibition of tumor cell growth when compared to untreated controls (p < 0.05). Together, these observations showed an inverse correlation between PDEF and survivin expression and suggested that increased PDEF expression along with reduced survivin was associated with prolonged survival of patients with ovarian cancer.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Proteínas Proto-Oncogênicas c-ets/biossíntese , Antineoplásicos/farmacologia , Western Blotting , Linhagem Celular Tumoral , Feminino , Humanos , Imuno-Histoquímica , Proteínas Inibidoras de Apoptose , Estimativa de Kaplan-Meier , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas de Neoplasias/metabolismo , Estadiamento de Neoplasias , Neoplasias Ovarianas/mortalidade , Prognóstico , Proteínas Proto-Oncogênicas c-ets/efeitos dos fármacos , RNA Mensageiro/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Survivina
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA