Omics-Based Approaches for the Characterization of Pompe Disease Metabolic Phenotypes.

Lysosomal storage disorders (LSDs) constitute a large group of rare, multisystemic, inherited disorders of metabolism, characterized by defects in lysosomal enzymes, accessory proteins, membrane transporters or trafficking proteins. Pompe disease (PD) is produced by mutations in the acid alpha-glucosidase (GAA) lysosomal enzyme. This enzymatic deficiency leads to the aberrant accumulation of glycogen in the lysosome. The onset of symptoms, including a variety of neurological and multiple-organ pathologies, can range from birth to adulthood, and disease severity can vary between individuals. Although very significant advances related to the development of new treatments, and also to the improvement of newborn screening programs and tools for a more accurate diagnosis and follow-up of patients, have occurred over recent years, there exists an unmet need for further understanding the molecular mechanisms underlying the progression of the disease. Also, the reason why currently available treatments lose effectiveness over time in some patients is not completely understood. In this scenario, characterization of the metabolic phenotype is a valuable approach to gain insights into the global impact of lysosomal dysfunction, and its potential correlation with clinical progression and response to therapies. These approaches represent a discovery tool for investigating disease-induced modifications in the complete metabolic profile, including large numbers of metabolites that are simultaneously analyzed, enabling the identification of novel potential biomarkers associated with these conditions. This review aims to highlight the most relevant findings of recently published omics-based studies with a particular focus on describing the clinical potential of the specific metabolic phenotypes associated to different subgroups of PD patients.

Pharmacometric characterization of entero-hepatic circulation processes of orally administered formulations of amiodarone under complex binding kinetics.

AIMS: The aims of this work are (i) to characterize the absorption properties of orally administered formulations at different dose levels, and (ii) to evaluate the impact of entero-hepatic circulation on the time-course of amiodarone (AM) in rats in order to optimize the development of new oral (OR) formulations. METHODS: Intravenous (IV) formulation consisted on a solution of a commercial injectable of AM chlorhydrate. OR formulations included the IV commercial formulation (Trangorex®) (Solution I), an aqueous supramicellar solution of AM chlorhydrate with Polysorbate at 5% (Solution II) and a suspension from Trangorex® tablets (Tablet). Data from 96 male Wistar rats, including 985 AM observations, were analyzed using NONMEM v7.4. RESULTS: The population pharmacokinetic (PK) model assumes linear absorption processes, showing ka of AM from Solution II (Polysorbate 80, 5%) and Solution I increased by 2.5- and 1.62-fold compared to Tablet formulation. OR bioavailability of AM from Tablet, Solution I and Solution II was 37%, 40%, and 50%, respectively. The structural model of AM disposition was adapted from a previously population PK model and expanded by incorporating entero-hepatic reabsorption (EHR) processes, which estimated a 12.3% biliary excretion of AM and complete re-absorption from lumen. CONCLUSIONS: The current population PK model of AM demonstrated the absorption rate enhancement when AM is formulated with supramicellar concentrations of Polysorbate 80. The study design allowed to characterize the EHR of AM and its contribution in the overall AM disposition.

Impact of Pharmacokinetic and Pharmacodynamic Properties of Monoclonal Antibodies in the Management of Psoriasis.

The treatment of psoriasis has been revolutionized by the emergence of biological therapies. Monoclonal antibodies (mAb) generally have complex pharmacokinetic (PK) properties with nonlinear distribution and elimination. In recent years, several population pharmacokinetic/pharmacodynamic (PK/PD) models capable of describing different types of mAb have been published. This study aims to summarize the findings of a literature search about population PK/PD modeling and therapeutic drug monitoring (TDM) of mAb in psoriasis. A total of 22 articles corresponding to population PK/PD models of tumor necrosis factor (TNF)-α inhibitors (adalimumab and golimumab), interleukin (IL)-23 inhibitors (guselkumab, tildrakizumab, and risankizumab), IL-23/IL-12 inhibitor (ustekinumab), and IL-17 inhibitors (secukinumab, ixekizumab, and brodalumab) were collected. A summary of the clinical trials conducted so far in psoriasis was included, together with the current structural population PK and PD models. The most significant and clinical covariates were body weight (BW) and the presence of immunogenicity on clearance (CL). The lack of consensus on PK/PD relationships has prevented establishing an adequate dosage and, therefore, accentuates the need for TDM in psoriasis.

Quantitative assessment of the exposure-efficacy relationship of glucocerebrosidase using Markovian elements in Gaucher patients treated with enzyme replacement therapy.

AIMS: The aims of this study are (i) to develop a population pharmacokinetic model of enzyme activity in Gaucher-type 1 (GD1) patients after intravenous administration of enzyme replacement therapy (ERT), and (ii) to establish an exposure-efficacy relationship for bone marrow infiltration to propose dose adjustments according to patient covariate values. METHODS: A prospective follow-up, semi-experimental multi-centre study was conducted in four hospitals to evaluate the pharmacokinetics, efficacy and safety of ERT in GD1 patients. Twenty-five individuals with 266 glucocerebrosidase (GCase) observations in plasma and leukocytes and 14 individuals with 68 Spanish magnetic resonance imaging (S-MRI) observations were enrolled. RESULTS: A two concatenated compartment model with zero-order endogenous production and first-order distribution (CL1 = 3.85 × 10-1 L/d) and elimination (CL2 = 1.25 L/d) allowed GCase observations in plasma and leukocytes to be described, respectively. An exponential time dependency (kT = 6.14 × 10-1 d-1 ) effect on CL1 was incorporated. The final exposure-efficacy model was a longitudinal logistic regression model with a first-order Markov element. An Emax function (EC50 = 15.73 U/L and Emax = 2.33) linked steady-state concentrations of GCase in leukocytes to the probability of transition across the different S-MRI stages. CONCLUSION: A population pharmacokinetic model successfully characterized the leukocyte activity-time profiles of GCase following intravenous administration of ERT in GD1 patients together with an exposure-efficacy relationship in bone marrow using Markovian elements. The information obtained from this study could be of high clinical relevance in individualization of ERT in GD1 patients, as this could lead to anticipative decision-making regarding clinical response in bone and optimal dosing strategy.

Physicochemical stability of binary admixtures of paracetamol and dexketoprofen-trometamol for patient-controlled analgesia use.

BACKGROUND: Intravenous admixtures of dexketoprofen-trometamol and paracetamol are frequently used in clinical practice due to synergism obtained administering both drugs concomitantly. Physicochemical stability of binary admixture containing both drugs is currently unknown. OBJECTIVE: To determine physicochemical stability of binary admixture containing dexketoprofen-trometamol 50 mg and paracetamol 1000 mg in a low-density polyethylene bottle at different storage conditions of light and temperature for advanced preparation. METHODS: Eight mixtures containing dexketoprofen-trometamol (Enantyum ampule 2 mL) 50 mg and paracetamol (Paracetamol B. Braun bottle 100 mL) 1000 mg were prepared and stored at: room temperature and exposed to light; room temperature and protected from light; refrigerated and exposed to light; and refrigerated and protected from light. From each mixture, aliquots were extracted at different times for 15 days. For physical compatibility, pH measure, gravimetric analysis and visual inspection were carried out. For chemical stability, concentrations of dexketoprofen-trometamol and paracetamol were simultaneously measured by high performance liquid chromatography. RESULTS: Only refrigerated mixtures showed incompatibility since white precipitation appeared at day 6, possibly due to paracetamol instability. Remaining drugs concentrations were in all cases≥90% after 15 days. CONCLUSION: Binary mixture containing paracetamol (100 mL) 1000 mg and dexketoprofen-trometamol (2 mL) 50 mg in a low-density polyethylene bottle is physicochemically stable for 5 days under refrigeration and 15 days at room temperature. By considering also microbial contamination, this mixture can be prepared in advance, 5 days stored refrigerated and 2 days stored at room temperature, being unnecessary protection from light.

Evaluación de la eficacia de fosfomicina trometamol y gentamicina en la profilaxis de la cistoscopia flexible tras el estudio de los patógenos de nuestro entorno / Evaluation of the Efficacy of Fosfomycin Trometamol and Gentamicin in the Prophylaxis of Flexible Cystoscopy after the Study of Microflora in our Environment

Objetivo Optimizar el uso de antibióticos en la profilaxis de la cistoscopia flexible estudiando los patógenos más frecuentes de nuestro entorno y eligiendo el antibiótico según sus antibiogramas. Métodos Desde Enero del 2015 hasta Noviembre del 2015, se analizaron los urinocultivos de nuestra área, se eligió el antibiótico en función a su sensibilidad frente a los patógenos más frecuentes y se comparó con un antibiótico de amplio espectro. Desde Enero del 2016 hasta Diciembre del 2016, se realizaron las cistoscopias agrupando a los pacientes en: Grupo 1: Pacientes sin profilaxis; Grupo 2: Profilaxis con Gentamicina 240 mg; Grupo 3: Profilaxis con antibiótico seleccionado. Como variables principales se definieron la presencia de bacteriuria asintomática e ITU tras la realización de la cistoscopia flexible. Resultados Se analizaron 8.530 urinocultivos y se eligió la Fosfomicina Trometamol 3 gr como profilaxis. Se realizaron 244 cistoscopias distribuidas: Grupo 1: 86 (35%); Grupo 2: 72 (30%); Grupo 3: 86 (35%). Se detectó bacteriuria asintomática postcistoscopia en 6 pacientes (2,5%) en el Grupo 1, 7 pacientes (2,9%) en el grupo 2 y 5 pacientes (2%) en el grupo 3 no presentando diferencias significativas (p 0.120). Desarrollaron ITUs postcistoscopia 1 paciente (0,4%) en el Grupo 1, 5 pacientes (2%) en el Grupo 2 y 2 pacientes (0,8%) en el Grupo 3 sin diferencias significativas (p 0.105). Conclusión La Fosfomicina es tan efectiva como la Gentamicina en la profilaxis de la cistoscopia. Para un uso correcto de los antibióticos, se recomienda el estudio de los patógenos de nuestro entorno.

Objective To optimize the use of antibiotics in the prophylaxis of flexible cystoscopy by studying the most frequent pathogens in our environment and choosing the antibiotic according to its antibiograms. Method Between January 2015 and November 2015, urine cultures were analyzed in our area, the antibiotic was chosen based on its sensitivity to the most frequent pathogens and compared with a broad spectrum antibiotic. From January 2016 to December 2016, cystoscopy was performed by grouping patients into: Group 1 - Patients without prophylaxis, Group 2 - Prophylaxis with 240 mg gentamicin, Group 3 - Selected antibiotic prophylaxis. The main variables were the presence of asymptomatic bacteriuria and UTI after flexible cystoscopy. Results 8530 urine cultures were analyzed and 3 g of fosfomycin trometamol was chosen as the prophylactic. There were 244 cystoscopies: Group 1: 86 (35%); Group 2: 72 (30%); Group 3: 86 (35%). Asymptomatic bacteriuria was detected in 6 patients (2.5%) in Group 1, 7 patients (2.9%) in Group 2 and 5 patients (2%) in Group 3, showing no significant differences (p = 0.120). Post-cystoscopic urinary tract infection developed in 1 patient (0.4%) in Group 1, 5 patients (2%) in Group 2 and 2 patients (0.8%) in Group 3, which showed no significant differences (p 0.105). Conclusion Fosfomycin is as effective as Gentamicin as a prophylactic in cystoscopy. The study of the pathogens in each environment is recommended to correctly prescribe the antibiotic.

Relationship Between Glucocerebrosidase Activity and Clinical Response to Enzyme Replacement Therapy in Patients With Gaucher Disease Type I.

The quantification of enzyme activity in the patient treated with enzyme replacement therapy (ERT) has been suggested as a tool for dosage individualization, so we conducted a study to evaluate the relationship between glucocerebrosidase activity and clinical response in patients with Gaucher disease type I (GD1) to ERT. The study included patients diagnosed with GD1, who were being treated with ERT, and healthy individuals. Markers based on glucocerebrosidase activity measurement in patients' leucocytes were studied: enzyme activity at 15 min. post-infusion (Act75 ) reflects the amount of enzyme that is distributed in the body post-ERT infusion, and accumulated glucocerebrosidase activity during ERT infusion (Act75-0 ) indicates the total drug exposure during infusion. The clinical response was evaluated based on criteria established by Pastores et al. and Gaucher Severity Score Index. Statistical analysis included ROC analysis and area under the curve test. Act75 and Act75-0 were found to be moderate predictive markers of an optimal clinical response (area under the ROC of Act75 was 0.733 and Act75-0 was 0.817). Act75-0 showed statistical significance in its discriminative capacity (p < 0.05) for obtaining an optimal response to ERT. The cut-off point was 58% (RR = 1.800; 95% CI: 1.003-3.229; p < 0.05). Moreover, Act75 showed a significant and inverse correlation with the Gaucher Severity Score Index, and Act75 and Act75-0 presented a significant correlation with residual enzyme activity at diagnosis. Markers based on glucocerebrosidase activity have a good correlation with clinical response to ERT. Therefore, it could provide supporting clinical data for dose management in GD1 patients.

Cellular Uptake of Glucocerebrosidase in Gaucher Patients Receiving Enzyme Replacement Treatment.

BACKGROUND: Enzyme replacement therapy (ERT) is currently the standard treatment for patients with Gaucher disease type I (GD1), but the pharmacokinetics have hardly been studied. This study aimed to quantify in vivo enzyme activity in peripheral leukocytes from patients receiving long-term treatment with imiglucerase or velaglucerase for GD1, and set out to assess the process of enzymatic uptake by peripheral leukocytes. METHODS: A prospective semi-experimental study was conducted. Four time points for blood withdrawal were planned per patient to quantify the intra-leukocyte enzymatic activity. In order to assess the uptake process, the rate of enzyme uptake by leukocytes (Rupt) and the rate of enzyme disappearance from the plasma (Rdis) were estimated. RESULTS: Eight GD1 patients were included. Intra-leukocyte activity was 24.31 mU/mL [standard deviation (SD) 6.32 mU/mL; coefficient of variation (CV) 25.96 %] at baseline and 27.14 mU/mL (SD  6.96 mU/mL; CV 25.65 %) at 15 min post-perfusion. The relationships with the administered dose were linear. The Rupt value was 37.73 mU/mL/min [95 % confidence interval (CI) 25.63-49.84] and showed a linear correlation with the administered enzyme dose (p < 0.05), and the Rdis value was 189.43 mU/mL/min (95 % CI 80.31-298.55) and also showed a linear correlation with the dose (p < 0.05). CONCLUSION: This was the first in vivo study to quantify the accumulated enzymatic activity in patients receiving ERT for GD1. It showed that intra-leukocyte activity at baseline and at 15 min post-perfusion could be used as a possible marker for therapeutic individualization in patients receiving ERT for GD1.

Consensus on the criteria needed for creating a rare-disease patient registry. A Delphi study.

BACKGROUND: Patient registries (PRs) are important tools for public-health surveillance and rare-disease research. The purpose of this study is to identify the most important criteria for the creation of a rare-disease PR that could be used by public-health authorities to develop health policies. METHODS: A consensus-development Delphi study was used, with participants selected for their expertize in rare diseases and registries. Participants were asked to complete a questionnaire on the most important criteria for creating PRs. Three rounds were performed. RESULTS: Agreement was reached on half the questions in the first round and on 89% of questions in the final round, with a total expert participation rate of around 60% by the final stage. This study made it possible to reach a broader consensus starting from experts' initial assessment of the features that should be considered for the creation of a rare-disease PR. CONCLUSION: The consensus method used made it possible to define the characteristics of a PR based on expert opinion within a rare-disease framework. This study may serve as a guide for helping other researchers plan and build a rare-disease PR.