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CONTEXT: The effect of liraglutide in C-peptide-positive (C-pos) type 1 diabetes (T1D) patients during hypoglycemia remains unclear. OBJECTIVE: To investigate the effect of a 12-week liraglutide treatment on the body glucose fluxes during a hypoglycemic clamp in C-pos T1D patients and its impact on the alpha- and beta-cell responses during hypoglycemia. DESIGN: This was a randomized, double-blind, crossover study. Each C-pos T1D patient was allocated to the treatment sequence liraglutide/placebo or placebo/liraglutide with daily injections for 12 weeks adjunct to insulin treatment, separated by a 4-week washout period. SETTING AND PARTICIPANTS: Fourteen T1D patients with fasting C-peptideâ ≥â 0.1 nmol/L. INTERVENTION(S): All patients underwent a hyperinsulinemic-stepwise-hypoglycemic clamp with isotope tracer [plasma glucose (PG) plateaus: 5.5, 3.5, 2.5, and 3.9 mmol/L] after a 3-month liraglutide (1.2 mg) or placebo treatment. MAIN OUTCOME MEASURE(S): The responses of endogenous glucose production (EGP) and rate of peripheral glucose disposal (Rd) were similar for liraglutide and placebo treatment during the clamp. RESULTS: The numbers of hypoglycemic events were similar in both groups. At the clamp, mean glucagon levels were significantly lower at PG plateau 5.5 mmol/L in the liraglutide than in the placebo group but showed similar responses to hypoglycemia in both groups. Mean C-peptide levels were significantly higher at PG-plateaus 5.5 and 3.5 mmol/L after liraglutide treatment, but this effect was not reflected in EGP and Rd. Hemoglobin A1c and body weight were lower, and a trend for reduced insulin was seen after liraglutide treatment. CONCLUSIONS: The results indicate that 3 months of liraglutide treatment does not promote or prolong hypoglycemia in C-pos T1D patients.
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Diabetes Mellitus Tipo 1 , Hipoglicemia , Glicemia , Peptídeo C , Estudos Cross-Over , Diabetes Mellitus Tipo 1/tratamento farmacológico , Método Duplo-Cego , Glucose , Hemoglobinas Glicadas/análise , Humanos , Hipoglicemia/induzido quimicamente , Hipoglicemia/tratamento farmacológico , Hipoglicemiantes/efeitos adversos , Liraglutida/efeitos adversos , Resultado do TratamentoRESUMO
The aim was to evaluate whether an in vitro release test (IVRT) could differentiate the release rates from five pharmaceutically equivalent acyclovir cream products and one ointment compared to that from a reference product, Zovirax cream (USA), to identify a test product with an inequivalent drug release rate that could serve as negative control for bioequivalence (BE) in a separate in vivo study. The reference product showed equivalent drug release rates compared to itself. The six test products failed to show equivalent drug release rates compared to the reference product. Aciclovir 1A pharma cream was selected to serve as a negative control for subsequent BE studies, since it exhibited the greatest difference in release rate among all creams, compared to the reference product. The results of this study indicate that IVRT results can be highly sensitive and may discriminate clinically relevant differences between products. Results from an appropriately validated IVRT method can support a demonstration of BE by showing that the drug release rates from test and reference products are statistically equivalent, mitigating the risk that differences may exist between the products which may influence in vivo performance of the drug product.
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Aciclovir , Antivirais , Liberação Controlada de Fármacos , Pomadas , Equivalência TerapêuticaRESUMO
OBJECTIVE: To implement OFM-recirculation and OFM-suction capable of direct and absolute in-vivo quantification of albumin in the ISF of pigs. APPROACH: OFM-recirculation and OFM-suction were used to collect ISF in-vivo in pigs and lymph was collected from the same pigs after OFM sampling. Blood was collected before and after OFM sampling, plasma was isolated and mean albumin plasma concentrations per pig were used to yield albumin ISF-to-plasma ratios. We characterized the quality of the collected undiluted ISF via (1) stable albumin ISF-to-plasma ratio in OFM-recirculation and in OFM-suction samples, (2) comparison of albumin ISF-to-plasma ratios from OFM-recirculation and OFM-suction and (3) comparison of normalized albumin concentrations in the ISF and lymph. MAIN RESULTS: Both advanced OFM methods were successfully implemented and albumin was quantified from the collected ISF samples. OFM-recirculation reached stable albumin ISF-to-plasma ratios after 20 recirculation cycles. Absolute ISF albumin concentrations were 11.2 mg ml-1 (OFM-recirculation) and 14.2 mg ml-1 (OFM-suction). Albumin ISF-to-plasma ratios were 0.39 ± 0.04 (OFM -recirculation) and 0.47 ± 0.1 (OFM-suction). SIGNIFICANCE: Knowledge of the ISF protein content is of major importance when assessing PK/PD effects, especially of highly protein bound drugs. Up to now, only blood albumin values have been available to determine the degree of protein binding in several tissues. OFM-recirculation and OFM-suction allow direct, absolute quantification of albumin in ISF for the first time and enable investigation of the degree of protein binding of a drug directly in its target tissue.
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Albuminas , Líquido Extracelular , Perfusão , Animais , Sucção , SuínosRESUMO
Maintaining good glycaemic control with the same infusion set for longer than 3 days may improve the quality of life of insulin pump users. The aim of the current study was to assess the efficacy and safety of the novel, extended-wear infusion set over 7 days of wear in adults with type 1 diabetes. Sixteen participants completed three identical 8-hour euglycaemic clamp experiments on Days 1, 4 and 7 of infusion set wear. Between the experiments, the participants were discharged home for routine diabetes management while wearing the same extended-wear infusion set throughout the study. Time to reach the maximum glucose infusion rate (TGIRmax ) on Day 7 was reduced by 67% compared with Day 1 (p < .001). The corresponding area under the glucose infusion rate curve (AUCGIR ) was comparable for the first 2 h of the clamp (p = .891) but decreased by 28% over time (p < .008). While the extent of insulin absorption decreased with prolonged wear, it was accompanied by an increase in insulin absorption rate. The infusion set survival rate was 100% without leakages, occlusion alarms, severe hypoglycaemia or ketoacidosis. The extended-wear infusion set proved safe and effective during prolonged wear in real-life conditions.
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Diabetes Mellitus Tipo 1 , Adulto , Glicemia , Diabetes Mellitus Tipo 1/tratamento farmacológico , Técnica Clamp de Glucose , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Sistemas de Infusão de Insulina , Qualidade de Vida , TecnologiaRESUMO
OBJECTIVE: To investigate the pharmacokinetic and pharmacodynamic properties and safety of a novel formulation of insulin aspart (AT247) versus two currently marketed insulin aspart formulations (NovoRapid [IAsp] and Fiasp [faster IAsp]). RESEARCH DESIGN AND METHODS: This single-center, randomized, double-blind, three-period, crossover study was conducted in 19 men with type 1 diabetes, receiving single dosing of trial products (0.3 units/kg) in a random order on three visits. Pharmacokinetics and pharmacodynamics were assessed during a euglycemic clamp lasting up to 8 h. RESULTS: Onset of insulin appearance was earlier for AT247 compared with IAsp (-12 min [95% CI -14; -8], P = 0.0004) and faster IAsp (-2 min [-5; -2], P = 0.0003). Onset of action was accelerated compared with IAsp (-23 min [-37; -15], P = 0.0004) and faster IAsp (-9 min [-11; -3], P = 0.0006). Within the first 60 min, a higher exposure was observed for AT247 compared with IAsp by the area under the curve (AUC) glucose infusion rate (GIR) from 0 to 60 min (AUCAsp0-60min: treatment ratio vs. IAsp 2.3 [1.9; 2.9] vs. faster IAsp 1.5 [1.3; 1.8]), which was underpinned by a greater early glucose-lowering effect (AUCGIR,0-60min: treatment ratio vs. IAsp 2.8 [2.0; 5.5] vs. faster IAsp 1.7 [1.3; 2.3]). Furthermore, an earlier offset of exposure was observed for AT247 compared with IAsp (-32 min [-58; -15], P = 0.0015) and faster IAsp (-27 min [-85; -15], P = 0.0017), while duration of the glucose-lowering effect, measured by time to late half-maximum effect, did not differ significantly. CONCLUSIONS: AT247 exhibited an earlier insulin appearance, exposure, and offset, with corresponding enhanced early glucose-lowering effect compared with IAsp and faster IAsp. It therefore represents a promising candidate in the pursuit for second-generation prandial insulin analogs to improve postprandial glycemic control.
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Diabetes Mellitus Tipo 1 , Insulina Aspart , Glicemia , Estudos Cross-Over , Diabetes Mellitus Tipo 1/tratamento farmacológico , Método Duplo-Cego , Humanos , Hipoglicemiantes/efeitos adversos , Insulina , Insulina Aspart/efeitos adversos , MasculinoRESUMO
PURPOSE: Dermal open flow microperfusion (dOFM) has previously demonstrated its utility to assess the bioequivalence (BE) of topical drug products in a clinical study. We aimed to characterize the sources of variability in the dermal pharmacokinetic data from that study. METHODS: Exploratory statistical analyses were performed with multivariate data from a clinical dOFM-study in 20 healthy adults evaluating the BE, or lack thereof, of Austrian test (T) and U.S. reference (R) acyclovir cream, 5% products. RESULTS: The overall variability of logAUC values (CV: 39% for R and 45% for T) was dominated by inter-subject variability (R: 82%, T: 91%) which correlated best with the subject's skin conductance. Intra-subject variability was 18% (R) and 9% (T) of the overall variability; skin treatment sites or methodological factors did not significantly contribute to that variability. CONCLUSIONS: Inter-subject variability was the major component of overall variability for acyclovir, and treatment site location did not significantly influence intra-subject variability. These results support a dOFM BE study design with T and R products assessed simultaneously on the same subject, where T and R treatment sites do not necessarily need to be next to each other. Localized variation in skin microstructure may be primarily responsible for intra-subject variability.
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Aciclovir/farmacocinética , Perfusão/métodos , Pele/efeitos dos fármacos , Pele/metabolismo , Aciclovir/administração & dosagem , Administração Cutânea , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Absorção Cutânea , Equivalência TerapêuticaRESUMO
Understanding the isomeric behavior of active ingredients in the soil and water environment is the first and a major part of deriving an exposure assessment. Whilst a variety of approaches have been taken previously, with the new regulatory framework for the risk assessment of isomeric plant protection compounds recently published by EFSA, (European Food Safety Authority) there will in future be a more consistent approach which has been taken here. For indaziflam (IAF), the alkylazine, cross spectrum residual herbicide which has a cellulose biosynthesis inhibition mode of action, there was no published data on the isomeric degradation behavior in soil and water. The results of measuring the isomeric stability of [14C]-radiolabeled 437-IAF, the major stereoisomer of indaziflam (AE 1170437, [1R,2S,6R] configuration) during its degradation in an aerobic soil metabolism study with four EU soils, an aerobic aquatic metabolism study with two natural water/sediment test systems, as well as an aqueous photolysis study are reported. To sum up, it was shown that in the different environmental conditions under abiotic as well as biotic degradation processes, indaziflam was not subject to isomeric interconversion to diastereoisomers 435-IAF (RRR), 438-IAF (RSS), or 439-IAF (SSR). Thus, all three chiral centers of indaziflam can be considered isomerically stable. In addition, no isomeric interconversion was observed at the 1-fluoroethyl position for the major degradation products IAF-indanone and IAF-carboxylic acid to the RSS-configuration as well as IAF-diaminotriazine from the R- to the S-configuration.
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BACKGROUND: Acute hospitals are generally not designed for people with dementia. Behavioral issues pose the greatest challenge. This article reports on the results of a prospective controlled study designed to assess whether dementia patients benefit from a remobilization strategy in a memory clinic (IG-MA) following hospital discharge. METHODS: Between January and September 2018 patients with moderate to severe dementia discharged from hospital following acute episodes were admitted to an IG-MA for remobilization. The IG-MA unit provides specially qualified personnel and an adapted environment. Control groups were formed from the standard remobilization unit (KG1-AGR) and four care homes (KG2-PWH). RESULTS: Patients in the IG-MA (nâ¯= 22) had a worse functional status at admission according to the Barthel index (BI), the timed "up and go" test (TUG) and the Esslinger transfer scale (ETS) than patients in the KG1-AGR (nâ¯= 59). Outcomes significantly improved in both groups (IG-MA and KG1-AGR) without a clear difference between groups: IG-MA (BI from 35 to 57.8 points, TUG from 30.8â¯s to 23â¯s, ETS from 2.1 to 1.1 points) vs. KG1-AGR (BI from 44.7 to 62.4 points, TUG from 28.6â¯s to 20.2â¯s, ETS from 1.7 to 0.9 points). There were differences in cognitive ability at admission (mini mental state examination, MMSE: IG-MA 13.6 points vs. KG1-AGR 20 points). The length of stay in the IG-MA was on average 5 days longer. Early discharge was mostly the result of complications and transfer to acute hospitals in the IG-MA group (22.7%) and in the KG1-AGR group this was mostly due to care issues (27.1%). The KG2-PWH group did not show any significant functional improvements in the first 4 weeks as measured by the BI. CONCLUSION: Moderate to severely affected dementia patients with behavioral problems benefited from treatment in a specially designed remobilization unit following hospital discharge after an acute event.
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Demência/reabilitação , Pacientes Internados , Alta do Paciente , Modalidades de Fisioterapia , Hospitalização , Humanos , Estudos Prospectivos , Recuperação de Função Fisiológica , Resultado do TratamentoRESUMO
Background: This two-center pilot study combined for the first time an intra-arterial glucose sensor with a decision support system for insulin dosing (SGCplus system) in critically ill patients with hyperglycemia. Methods: Twenty-two patients who were equipped with an arterial line and required iv insulin therapy were managed by the SGCplus system during their medical treatment at the intensive care unit. Results: Time to target was 111 ± 195 min (80-150 mg/dL) and 135 ± 267 min (100-160 mg/dL) in the lower and higher glucose target group. Mean blood glucose (BG) was 142 ± 32 mg/dL with seven BG values <70 mg/dL. Mean daily insulin dose was 62 ± 38 U and mean daily carbohydrate intake 148 ± 50 g/day (enteral nutrition) and 102 ± 58 g/day (parenteral nutrition). Acceptance of SGCplus suggestions was high (93%). Conclusions: The SGCplus system can be safely applied in critically ill patients with hyperglycemia and enables good glycemic control.
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Glicemia/análise , Cuidados Críticos/métodos , Estado Terminal , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Idoso , Algoritmos , Confiabilidade dos Dados , Diabetes Mellitus/tratamento farmacológico , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos PilotoRESUMO
OBJECTIVE: The aim of this study was to determine a potential benefit of the specific psychoeducational intervention "Learning to Live with Cancer" (LTLWC) for patients with operated nonmetastatic breast cancer, with respect to psychological variables and endocrine and immune parameters. METHODS: Fifty-two postmenopausal women with operated stage I to III breast cancer were randomized to either a breast cancer intervention group (BCIG, n = 30) who immediately began participating in the LTLWC intervention program or to a breast cancer control group (BCCG, n = 22). Matched healthy women were asked to participate as a noncancer comparison group (n = 26). All participants were evaluated at three different time points (t1-t3) using a set of standardized questionnaires and blood samples were taken to analyze immune cell subsets and stress hormone levels. RESULTS: A significant reduction in trait anxiety/State Trait Anxiety Inventory score was observed in the BCIG (t1: median = 35.0 [interquartile range = 28.0-38.0] versus t3: median = 26.0 [interquartile range = 18.5-37.0], p = .0001) compared with the BCCG (t1: median = 41.0 [interquartile range =32.75-49.0]; t3: median = 38.5 [interquartile range = 30.75-46.5], p = .01524; p interaction = .001). In parallel, a significant rise of serotonin levels (t1: median = 66.5 ng/ml [interquartile range = 11.50-106.00] versus t3: median = 80.5 ng/ml [interquartile range =59.00-118.00], p = .00008) as well as a significant reduction of the elevated number of Treg cells at baseline (t1: median = 4.45% [interquartile range = 4.00-5.33] versus t3: median = 2.80% [interquartile range = 2.68-3.13], p < .00001) were observed in the BCIG versus no change in the BCCG. A significant statistical association between reduced trait anxiety and decreased Treg cell number could be demonstrated in the BCIG (r = .62, p < .01). CONCLUSIONS: The observed results of this study provide preliminary support for the efficacy of the LTLWC program in significantly improving psychoneuroimmunological parameters in patients with nonmetastatic breast cancer.
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Ansiedade/terapia , Neoplasias da Mama , Avaliação de Resultados em Cuidados de Saúde , Educação de Pacientes como Assunto/métodos , Psicoterapia/métodos , Linfócitos T Reguladores , Idoso , Neoplasias da Mama/sangue , Neoplasias da Mama/imunologia , Neoplasias da Mama/psicologia , Neoplasias da Mama/terapia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Projetos Piloto , PsiconeuroimunologiaRESUMO
To compare the performance of a professional continuous glucose monitoring (proCGM) and a personal continuous glucose monitoring (persCGM) system worn in parallel under standardized conditions in individuals with type 1 diabetes (T1D), two CGM systems (iPro2 - proCGM; Minimed 640G - persCGM) worn in parallel using the same sensor (Enlite 2) were compared. Ten people with T1D were included in this single-centre, open-label study in which CGM performance was evaluated. The study consisted of a 24-hours inpatient phase (meals, exercise, glycaemic challenges) and a 4-day home phase. Analyses included fulfilment of ISO 15197:2013 criteria, mean absolute relative difference (MARD), Parkes Error Grid and Bland-Altman plots. During the inpatient stay, ISO 15197:2013 criteria fulfilment was 58.4% (proCGM) and 57.8% (persCGM). At home, the systems met ISO 15197:2013 criteria by 66.5% (proCGM) and 65.3% (persCGM). No difference of MARD in inpatient phase (19.1 ± 16.7% vs. 19.0 ± 19.6; P = 0.83) and home phase (18.6 ± 26.8% vs. 17.4 ± 21.3%, P = 0.87) was observed. All sensors performed less accurately during hypoglycaemia. ProCGM and persCGM showed similar performance during daytime and night-time for the inpatient and the home phase. However, sensor performance was reduced during hypoglycaemia for both systems.
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Automonitorização da Glicemia/instrumentação , Glicemia/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Hiperglicemia/diagnóstico , Hipoglicemia/diagnóstico , Monitorização Ambulatorial/instrumentação , Adulto , Diabetes Mellitus Tipo 1/tratamento farmacológico , Feminino , Humanos , Hiperglicemia/metabolismo , Hipoglicemia/metabolismo , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Masculino , Monitorização Fisiológica/instrumentação , Adulto JovemRESUMO
Context: Complete loss of ß-cell function in patients with type 1 diabetes mellitus (T1DM) may lead to an increased risk of severe hypoglycemia. Objective: We aimed to determine the impact of C-peptide status on glucagon response and endogenous glucose production (EGP) during hypoglycemia in patients with T1DM. Design and Setting: We conducted an open, comparative trial. Patients: Ten C-peptide positive (C-pos) and 11 matched C-peptide negative (C-neg) patients with T1DM were enrolled. Intervention: Plasma glucose was normalized over the night fast, and after a steady-state (baseline) plateau all patients underwent a hyperinsulinemic, stepwise hypoglycemic clamp with glucose plateaus of 5.5, 3.5, and 2.5 mmol/L and a recovery phase of 4.0 mmol/L. Blood glucagon was measured with a specific and highly sensitive glucagon assay. EGP was determined with a stable isotope tracer technique. Main Outcome Measure: Impact of C-peptide status on glucagon response and EGP during hypoglycemia. Results: Glucagon concentrations were significantly lower in C-pos and C-neg patients than previously reported. At baseline, C-pos patients had higher glucagon concentrations than C-neg patients (8.39 ± 4.6 vs 4.19 ± 2.4 pmol/L, P = 0.016, mean ± standard deviation) but comparable EGP rates (2.13 ± 0.2 vs 2.04 ± 0.3 mg/kg/min, P < 0.391). In both groups, insulin suppressed glucagon levels, but hypoglycemia revealed significantly higher glucagon concentrations in C-pos than in C-neg patients. EGP was significantly higher in C-pos patients at hypoglycemia (2.5 mmol/L) compared with C-neg patients. Conclusions: Glucagon concentrations and EGP during hypoglycemia were more pronounced in C-pos than in C-neg patients, which indicates that preserved ß-cell function may contribute to counterregulation during hypoglycemia in patients with T1DM.
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Glicemia/biossíntese , Peptídeo C/fisiologia , Diabetes Mellitus Tipo 1/sangue , Glucagon/biossíntese , Hipoglicemia/sangue , Adulto , Conscientização , Peptídeo C/sangue , Diabetes Mellitus Tipo 1/tratamento farmacológico , Esquema de Medicação , Epinefrina/sangue , Feminino , Glucagon/sangue , Técnica Clamp de Glucose/métodos , Humanos , Hipoglicemia/psicologia , Insulina/administração & dosagem , Insulina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Norepinefrina/sangue , Adulto JovemRESUMO
We evaluated a standard subcutaneous microdialysis technique for glucose monitoring in two critically ill patient populations and tested whether a prolonged run-in period improves the quality of the interstitial glucose signal. 20 surgical patients after major cardiac surgery (APACHE II score: 10.1 ± 3.2) and 10 medical patients with severe sepsis (APACHE II score: 31.1 ± 4.3) were included in this investigation. A microdialysis catheter was inserted in the subcutaneous adipose tissue of the abdominal region. Interstitial fluid and arterial blood were sampled in hourly intervals to analyse glucose concentrations. Subcutaneous adipose tissue glucose was prospectively calibrated to reference arterial blood either at hour 1 or at hour 6. Median absolute relative difference of glucose (MARD), calibrated at hour 6 (6.2 (2.6; 12.4) %) versus hour 1 (9.9 (4.2; 17.9) %) after catheter insertion indicated a significant improvement in signal quality in patients after major cardiac surgery (p < 0.001). Prolonged run-in period revealed no significant improvement in patients with severe sepsis, but the number of extreme deviations from the blood plasma values could be reduced. Improved concurrence of glucose readings via a 6-hour run-in period could only be achieved in patients after major cardiac surgery.
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Glicemia/metabolismo , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Microdiálise/normas , Monitorização Fisiológica/normas , Complicações Pós-Operatórias/sangue , Sepse/sangue , Idoso , Ensaios Clínicos como Assunto , Estado Terminal , Líquido Extracelular/metabolismo , Feminino , Humanos , Masculino , Microdiálise/métodos , Pessoa de Meia-Idade , Monitorização Fisiológica/métodosRESUMO
The rate of release of an active pharmaceutical ingredient (API) from a topical semisolid dosage form can be influenced by its physical and structural properties. An In Vitro Release Test (IVRT) is an established method to characterize this rate of API release and compare the underlying sameness in product quality characteristics. The purpose of this work was to validate an IVRT method to compare acyclovir cream, 5% products. However, despite widespread use of the IVRT since 1997, there has been no established approach to validate an IVRT method. Our approach included: 1) qualification of the diffusion cell apparatus, 2) qualification of the laboratory, 3) validation of the HPLC analytical method, and 4) validation of numerous critical parameters of the IVRT method, itself, and resulted in a comprehensive and successful IVRT method validation. Subsequent to the IVRT validation work described here, the U.S. Food and Drug Administration (FDA) drafted a guidance on the development and validation of an IVRT method for acyclovir cream, 5%. Although there are notable differences between our approach and the approach in that guidance, this report illustrates how many of the same essential qualification parameters and validation concepts were considered and systematically addressed in our approach to IVRT validation.
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Aciclovir/química , Antivirais/química , Química Farmacêutica/métodos , Cromatografia Líquida de Alta Pressão , Liberação Controlada de Fármacos , Pomadas/química , Reprodutibilidade dos TestesRESUMO
OBJECTIVE: Pharmacokinetic and pharmacodynamic studies of topically applied drugs are commonly performed by sampling of interstitial fluid with dermal open flow microperfusion and subsequent analysis of the samples. However, the reliability of results from the measured concentration-time profile of the penetrating drug suffers from highly variable skin permeability to topically applied drugs that is mainly caused by inter- and intra-subject variations of the stratum corneum. Thus, statistically significant results can only be achieved by performing high numbers of experiments. To reduce the expenditures needed for such high experiment numbers we aimed to assess the correlation between skin permeability and skin impedance/skin admittance. APPROACH: We performed an ex vivo drug penetration study with human skin, based on the hypothesis that inter-subject variations of the respective concentration-time profiles can be correlated with variations of the passive electrical properties of the skin. Therefore, skin impedance and skin admittance were related to the skin permeability to the model drug Clobetasol-17-proprionate. MAIN RESULTS: The measured low frequency skin impedance and the skin admittance correlated linearly with the drug concentration-time profiles from dermal sampling. SIGNIFICANCE: Skin permeability can be assessed by measuring the passive electrical properties of the skin, which enables correction of skin permeability variations. This allows reduction of experiment numbers in future pharmacokinetic and pharmacodynamic studies with human skin ex vivo and in vivo and leads to diminished study costs.
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Clobetasol/administração & dosagem , Clobetasol/metabolismo , Impedância Elétrica , Pele/metabolismo , Administração Cutânea , Humanos , Modelos Biológicos , PermeabilidadeRESUMO
BACKGROUND: Diabetes management requires complex and interdisciplinary cooperation of health care professionals (HCPs). To support this complex process, IT-support is recommended by clinical guidelines. The aim of this article is to report on results from a clinical feasibility study testing the prototype of a mobile, tablet-based client-server system for computerized decision and workflow support (GlucoTab®) and to discuss its impact on hypoglycemia prevention. METHODS: The system was tested in a monocentric, open, noncontrolled intervention study in 30 patients with type 2 diabetes mellitus (T2DM). The system supports HCPs in performing a basal-bolus insulin therapy. Diabetes therapy, adverse events, software errors and user feedback were documented. Safety, efficacy and user acceptance of the system were investigated. RESULTS: Only 1.3% of blood glucose (BG) measurements were <70 mg/dl and only 2.6% were >300 mg/dl. The availability of the system (97.3%) and the rate of treatment activities documented with the system (>93.5%) were high. Only few suggestions from the system were overruled by the users (>95.7% adherence). Evaluation of the 3 anonymous questionnaires showed that confidence in the system increased over time. The majority of users believed that treatment errors could be prevented by using this system. CONCLUSIONS: Data from our feasibility study show a significant reduction of hypoglycemia by implementing a computerized system for workflow and decision support for diabetes management, compared to a paper-based process. The system was well accepted by HCPs, which is shown in the user acceptance analysis and that users adhered to the insulin dose suggestions made by the system.
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Sistemas de Apoio a Decisões Clínicas , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemia/prevenção & controle , Hipoglicemiantes/administração & dosagem , Insulina/administração & dosagem , Aplicativos Móveis , Computadores de Mão , Diabetes Mellitus Tipo 2/sangue , Estudos de Viabilidade , Feminino , Humanos , Masculino , Fluxo de TrabalhoRESUMO
BACKGROUND: The availability of generic topical dermatological drug products is constrained by the limited methods established to assess topical bioequivalence (BE). A novel cutaneous pharmacokinetic approach, dermal open-flow microperfusion (dOFM), can continuously assess the rate and extent to which a topical drug becomes available in the dermis, to compare in vivo dermal bioavailability (BA) and support BE evaluations for topical products. OBJECTIVE: To evaluate whether dOFM is an accurate, sensitive, and reproducible in vivo method to characterize the intradermal BA of acyclovir from 5 % acyclovir creams, comparing a reference (R) product either to itself or to a different test (T) product. METHODS: In a single-center clinical study, R or T products were applied to six randomized treatment sites on the skin of 20 healthy human subjects. Two dOFM probes were inserted in each treatment site to monitor the intradermal acyclovir concentration for 36 h. Comparative BA (of R vs. R and T vs. R) was evaluated based on conventional BE criteria for pharmacokinetic endpoints (area under the curve and maximum dermal concentration) where the 90 % confidence interval of the geometric mean ratio between the T and R falls within 0.80-1.25. RESULTS: The positive control products (R vs. R) were accurately and reproducibly confirmed to be bioequivalent, while the negative control products (T vs. R) were sensitively discriminated not to be bioequivalent. CONCLUSIONS: dOFM accurately, sensitively, and reproducibly characterized the dermal BA in a manner that can support BE evaluations for topical acyclovir 5 % creams in a study with n = 40 (20 subjects in this study).
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Aciclovir/farmacocinética , Antivirais/farmacocinética , Microdiálise/métodos , Creme para a Pele/farmacocinética , Aciclovir/administração & dosagem , Administração Cutânea , Adulto , Antivirais/administração & dosagem , Área Sob a Curva , Feminino , Humanos , Masculino , Creme para a Pele/administração & dosagem , Equivalência TerapêuticaRESUMO
PURPOSE: To evaluate the kinetics of topically applied clobetasol-17-propionate (CP-17) in lesional and non-lesional psoriatic skin when released from a commercially available low-strength cream using in vivo dermal open-flow microperfusion (dOFM). METHODS: Twelve patients received Dermovate® cream (CP-17, 0.05%) on small lesional and non-lesional skin test sites for 14 days, once daily. On day 1 and 14, dOFM samples were continuously taken in the dermis for 24 h post-dose and analyzed by LC-MS/MS. Probe depths were assessed by 50 MHz ultrasound scanning. RESULTS: Mixed-effects modelling identified skin condition, treatment duration and probe-depth as kinetics determining variables. The time- and depth-resolved intradermal data revealed (i) slower penetration of CP-17 into lesional than into non-lesional skin, (ii) normalized (faster) skin penetration after repeated dosing, and (iii) no CP-17 accumulation within the dermis independently of the skin condition. CONCLUSIONS: Intradermal investigation of a highly lipophilic drug released from low-strength cream was successfully performed by using dOFM and timely and spatially, i.e., probe-depth dependent, resolved kinetic data were delivered. These data support the assumption that the thickened psoriatic stratum corneum might act as trap compartment which lowers the skin penetration rate for lipophilic topical drugs.
Assuntos
Clobetasol/administração & dosagem , Clobetasol/farmacocinética , Pele/efeitos dos fármacos , Pele/metabolismo , Administração Cutânea , Adulto , Cromatografia Líquida/métodos , Feminino , Humanos , Cinética , Masculino , Perfusão/métodos , Absorção Cutânea/fisiologia , Espectrometria de Massas em Tandem/métodosRESUMO
In recent years, genome-wide association studies (GWAS) have identified many loci that are shared among common disorders and this has raised interest in pleiotropy. For performing appropriate analysis, several methods have been proposed, e.g. conducting a look-up in external sources or exploiting GWAS results by meta-analysis based methods. We recently proposed the Compare & Contrast Meta-Analysis (CCMA) approach where significance thresholds were obtained by simulation. Here we present analytical formulae for the density and cumulative distribution function of the CCMA test statistic under the null hypothesis of no pleiotropy and no association, which, conveniently for practical reasons, turns out to be exponentially distributed. This allows researchers to apply the CCMA method without having to rely on simulations. Finally, we show that CCMA demonstrates power to detect disease-specific, agonistic and antagonistic loci comparable to the frequently used Subset-Based Meta-Analysis approach, while better controlling the type I error rate.