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1.
Article in English | MEDLINE | ID: mdl-38493439

ABSTRACT

Non-Small Cell Lung Cancer (NSCLC) remains one of the main causes of cancer death worldwide. In the urge of finding an effective approach to treat cancer, enormous therapeutic targets and treatment combinations are explored in clinical studies, which are not only costly, suffer from a shortage of participants, but also unable to explore all prospective therapeutic solutions. Within the evolving therapeutic landscape, the combined use of radiotherapy (RT) and checkpoint inhibitors (ICIs) emerged as a promising avenue. Exploiting the power of quantitative system pharmacology (QSP), we undertook a study to anticipate the therapeutic outcomes of these interventions, aiming to address the limitations of clinical trials. After enhancing a pre-existing QSP platform and accurately replicating clinical data outcomes, we conducted an in-depth study, examining different treatment protocols with nivolumab and RT, both as monotherapy and in combination, by assessing their efficacy through clinical endpoints, namely time to progression (TTP) and duration of response (DOR). As result, the synergy of combined protocols showcased enhanced TTP and extended DOR, suggesting dual advantages of extended response and slowed disease progression with certain combined regimens. Through the lens of QSP modeling, our findings highlight the potential to fine-tune combination therapies for NSCLC, thereby providing pivotal insights for tailoring patient-centric therapeutic interventions.

2.
Nat Chem ; 16(4): 556-563, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38374455

ABSTRACT

The distribution, metabolism and ultimate fate of molecules within the body is central to the activity of pharmaceuticals. However, the introduction of radioisotopes into the metabolically stable carbon sites on drugs to probe these features typically requires toxic, radioactive gases such as [14C]CO and [14C]CO2. Here we describe an approach to directly carbon-label carboxylic-acid-containing pharmaceuticals via a metal-catalysed functional group exchange reaction, forming 14C-labelled carboxylic-acid-containing drugs without radioactive gases, in one pot, using an easily available and handled carboxylic acid 14C source. To enable this process, a functional group metathesis of carbon-carbon covalent bonds in acid chloride functionalities is developed, exploiting the ability of nickel catalysts to both reversibly activate carbon-chloride bonds and exchange functionalities between organic molecules. The drug development applicability is illustrated by the direct incorporation of the 14C label or 13C label into an array of complex aryl, alkyl, vinyl and heterocyclic carboxylic acid drugs or drug candidates without gases or a special apparatus, at ambient conditions and without loss of the radiolabel.

3.
Chaos ; 34(1)2024 Jan 01.
Article in English | MEDLINE | ID: mdl-38277131

ABSTRACT

Sophistication of mathematical models in the pharmacological context reflects the progress being made in understanding physiological, pharmacological, and disease relationships. This progress has illustrated once more the need for advanced quantitative tools able to efficiently extract information from these models. While dynamical systems theory has a long history in the analysis of systems biology models, as emphasized under the dynamical disease concept by Mackey and Glass [Science 197, 287-289 (1977)], its adoption in pharmacometrics is only at the beginning [Chae, Transl. Clin. Pharmacol. 28, 109 (2020)]. Using a quantitative systems pharmacology model of tumor immune dynamics as a case study [Kosinsky et al., J. Immunother. Cancer 6, 17 (2018)], we here adopt a dynamical systems analysis to describe, in an exhaustive way, six different statuses that refer to the response of the system to therapy, in the presence or absence of a tumor-free attractor. To evaluate the therapy success, we introduce the concept of TBA, related to the Time to enter the tumor-free Basin of Attraction, and corresponding to the earliest time at which the therapy can be stopped without jeopardizing its efficacy. TBA can determine the optimal time to stop drug administration and consequently quantify the reduction in drug exposure.


Subject(s)
Neoplasms , Humans , Neoplasms/drug therapy , Models, Theoretical
4.
Angew Chem Int Ed Engl ; 62(10): e202213297, 2023 Mar 01.
Article in English | MEDLINE | ID: mdl-36576428

ABSTRACT

We describe here the development of a visible light driven nickel carbonylation catalyst. The combination of the large bite-angle Xantphos ligand with nickel(0) generates a catalyst capable of activating alkyl halides toward carbonylation at ambient temperature in the presence of blue light irradiation, and the reductive elimination of high energy acid chloride products. Unlike classical carbonylations, where the coordination of carbon monoxide inhibits the reactivity of earth abundant nickel catalysts, a CO-associated nickel is found to be the active catalyst in the reaction. Coupling the build-up of acid chlorides with nucleophile addition can be used to access various amides, esters and thioesters, including those of sterically encumbered substrates or with metal-reactive functionalities.

5.
Cancer Chemother Pharmacol ; 88(6): 997-1007, 2021 12.
Article in English | MEDLINE | ID: mdl-34536094

ABSTRACT

PURPOSE: Entrectinib (ROZLYTREK®) is a CNS-active, potent, and selective inhibitor of ROS1, TRK A/B/C, and ALK kinase activity. It was recently approved for the treatment of ROS1-positive non-small cell lung cancer and NTRK gene fusion-positive solid tumors. The main objective of this analysis was to characterize the pharmacokinetics (PK) of entrectinib and its main active metabolite, M5. METHODS: A total of 276 cancer patients receiving oral entrectinib were included in the analysis. A model-based population approach was used to characterize the PK profiles of both entities using NONMEM® 7.4. A joint model captures the PK of both entrectinib and M5. The effects of pH modifiers, formulation, weight, age, and sex on model parameters were assessed. Model performance was evaluated using visual predictive checks (VPCs). RESULTS: The absorption of entrectinib was best described using a sequential zero- and first-order absorption model and the disposition with one-compartment model for each entity with linear elimination. Moderate-to-high between-patient variability was estimated in model parameters (from 30.8% for the apparent clearance of entrectinib to 122% for the first-order absorption rate constant). Theory-based allometric scaling using body weight on clearances and volumes and a 28% lower relative bioavailability of the F1 formulation in pediatric patients were retained in the model. The VPC confirmed the good predictive performance of the PopPK model. CONCLUSIONS: A robust population PK model was built and qualified for entrectinib and M5, describing linear PK for both entities. This model was used to support the ROZLYTREK® new drug application.


Subject(s)
Benzamides/administration & dosage , Benzamides/pharmacokinetics , Indazoles/administration & dosage , Indazoles/pharmacokinetics , Neoplasms/drug therapy , Protein Kinase Inhibitors/administration & dosage , Protein Kinase Inhibitors/pharmacokinetics , Adolescent , Adult , Aged , Aged, 80 and over , Female , Follow-Up Studies , Humans , Male , Maximum Tolerated Dose , Middle Aged , Neoplasms/pathology , Prognosis , Tissue Distribution , Young Adult
6.
J ECT ; 37(4): 291-297, 2021 12 01.
Article in English | MEDLINE | ID: mdl-34294652

ABSTRACT

ABSTRACT: Depression is a major mental health disorder, and its pathophysiology is still largely unknown, as is the action mechanism of electroconvulsive therapy (ECT). Some evidence suggests that inflammation might play a role in depression, and several studies have attempted to demonstrate a link between ECT and cytokines. This systematic review used a qualitative analysis to assess the effect of ECT on inflammatory markers as it relates to the clinical response of depressive symptoms in major depressive disorders. The bibliographic search engines CINAHL, Embase, PsychInfo, and PubMed were used to identify articles published up to July 2020. Search terms related to depression, ECT, and inflammation were used. Descriptive statistical analyses were performed to relate changes in inflammatory markers to clinical response to ECT. Twenty-five studies were included in the analysis. No systematic increases or decreases were found in a given inflammatory marker over the ECT; however, we observed that tumor necrosis factor α and interleukin-6 (IL-6) were more often found to be decreased after ECT, whereas IL-8 and IL-10 were more often found to be increased after treatment. No trend in correlation was found between the degree of clinical improvement of depressive symptoms and the variation of any inflammatory markers, despite positive clinical response to ECT. Great heterogeneity with regard to methodology used and lack of power of the studies included in this review could explain the lack of systematic change and correlation found in this study. Future research conducted on this subject should take into account these methodological limitations to allow subsequent meta-analysis.


Subject(s)
Depressive Disorder, Major , Electroconvulsive Therapy , Biomarkers , Cytokines , Depression/therapy , Depressive Disorder, Major/therapy , Electroconvulsive Therapy/methods , Humans , Treatment Outcome
7.
Chaos ; 31(2): 023124, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33653032

ABSTRACT

Quantitative systems pharmacology (QSP) proved to be a powerful tool to elucidate the underlying pathophysiological complexity that is intensified by the biological variability and overlapped by the level of sophistication of drug dosing regimens. Therapies combining immunotherapy with more traditional therapeutic approaches, including chemotherapy and radiation, are increasingly being used. These combinations are purposed to amplify the immune response against the tumor cells and modulate the suppressive tumor microenvironment (TME). In order to get the best performance from these combinatorial approaches and derive rational regimen strategies, a better understanding of the interaction of the tumor with the host immune system is needed. The objective of the current work is to provide new insights into the dynamics of immune-mediated TME and immune-oncology treatment. As a case study, we will use a recent QSP model by Kosinsky et al. [J. Immunother. Cancer 6, 17 (2018)] that aimed to reproduce the dynamics of interaction between tumor and immune system upon administration of radiation therapy and immunotherapy. Adopting a dynamical systems approach, we here investigate the qualitative behavior of the representative components of this QSP model around its key parameters. The ability of T cells to infiltrate tumor tissue, originally identified as responsible for individual therapeutic inter-variability [Y. Kosinsky et al., J. Immunother. Cancer 6, 17 (2018)], is shown here to be a saddle-node bifurcation point for which the dynamical system oscillates between two states: tumor-free or maximum tumor volume. By performing a bifurcation analysis of the physiological system, we identified equilibrium points and assessed their nature. We then used the traditional concept of basin of attraction to assess the performance of therapy. We showed that considering the therapy as input to the dynamical system translates into the changes of the trajectory shapes of the solutions when approaching equilibrium points and thus providing information on the issue of therapy.


Subject(s)
Neoplasms , Humans , Immune System , Immunotherapy , Neoplasms/therapy , Systems Analysis , Tumor Microenvironment
8.
Int J Circumpolar Health ; 80(1): 1858605, 2021 12.
Article in English | MEDLINE | ID: mdl-33395372

ABSTRACT

In contrast to most Indigenous people in Canada, Inuit appeared until recently to have been protected from type 2 diabetes (T2D) related to obesity. We assessed the associations of metabolites (amino acids, acylcarnitines) with adiposity and biomarkers of T2D in school-aged Inuit children of Nunavik (Canada). Concentrations of metabolite were measured in plasma samples from a cross-sectional analysis of 248 children (mean age = 10.8 years). We assessed associations of plasma metabolites with adiposity measures (BMI, skinfold thicknesses) and T2D markers (insulin, glucose, adiponectin). Plasma concentrations of valine and tyrosine were higher in obese and overweight children compared to those of normal weight children (P < 0.05). An increment of 1-SD in BMI (SD = 3.3 kg/m2) was statistically associated with an increment of 0.21 (95% CI: 0.08, 0.33) for valine, 0.15 (95% CI: 0.02, 0.27) for isoleucine and 0.17 (95% CI: 0.04, 0.29) for tyrosine. Insulin concentration increased with concentrations of all amino acids (P < 0.05) except methionine. None of the acylcarnitines measured were statistically significantly associated with adiposity or T2D biomarkers A signature of metabolites, particularly higher levels of branched-chain amino acids, might allow for early detection of T2D among school-aged Inuit children.


Subject(s)
Adiposity , Diabetes Mellitus, Type 2 , Canada , Child , Cross-Sectional Studies , Diabetes Mellitus, Type 2/diagnosis , Glucose , Homeostasis , Humans , Inuit , Obesity/epidemiology , Quebec/epidemiology , Schools
9.
Dalton Trans ; 48(17): 5766-5772, 2019 Apr 23.
Article in English | MEDLINE | ID: mdl-30973572

ABSTRACT

We describe here the synthesis and structural characterization of two new classes of ambiphilic, N-boryl imine ligands, wherein boron is associated with a Lewis basic imine nitrogen. These ligands can be easily generated in two steps from the corresponding pyridinyl- and phosphinyl-tethered aldehydes. 11B NMR analysis suggests the association of the Lewis acidic boron to either the pyridine unit or via intermolecular acid/base interactions with the imine. Both of these ligands can coordinate to palladium, and their structures were confirmed by X-ray crystallography.

10.
Diabetes Res Clin Pract ; 140: 183-190, 2018 Jun.
Article in English | MEDLINE | ID: mdl-29626588

ABSTRACT

AIMS: Gestational diabetes mellitus (GDM) affects between 5 and 10% of all pregnancies in Canada and can lead to adverse health outcomes in both the mother and fetus. Amino acids (AA) and acylcarnitines (AC) have been identified as early biomarkers of type 2 diabetes but their usefulness in screening for GDM has yet to be demonstrated. METHODS: We conducted a nested case-control study involving 50 controls and 50 GDM cases diagnosed between the 24th and 28th week of gestation. Heparinized plasma samples were obtained during the first and early second trimester of pregnancy. Case and controls were matched according to date of recruitment, maternal age, gestational age at blood sampling as well as pre-pregnancy body mass index. Eight AA and eight AC were quantified using an ultra-high pressure liquid-chromatography quadrupole time-of-flight mass spectrometry platform. Conditional regression analyses adjusted for matching factors and smoking habits during pregnancy were performed to identify plasma metabolites associated with GDM risk. RESULTS: Odds ratio (OR) and 95% confidence interval (CI) for the prediction of GDM per one standard deviation increase of AA or AC in plasma levels were 0.25 (0.08-0.79) for butyrylcarnitine, 0.31 (0.12-0.79) for glutamic acid, 2.5 (1.2-5.3) for acetylcarnitine, 2.9 (1.3-6.8) for isobutyrylcarnitine and 5.3 (1.7-17.0) for leucine. These five metabolites were selected by stepwise conditional logistic regression to create a predictive model with an OR of 2.7 (1.5-4.9). CONCLUSION: Whether the identified metabolites can predict the risk of developing GDM requires additional studies in a larger sample of pregnant women.


Subject(s)
Amino Acids/adverse effects , Biomarkers/blood , Carnitine/analogs & derivatives , Diabetes, Gestational/blood , Adult , Carnitine/adverse effects , Case-Control Studies , Female , Humans , Pregnancy
11.
J Org Chem ; 82(22): 11891-11896, 2017 11 17.
Article in English | MEDLINE | ID: mdl-28770606

ABSTRACT

The role of hypervalent iodine reagents as oxidants has been widely recognized for more than 20 years. As electrophilic species, they could also play the role of Lewis acids. While not surprising, this aspect of these reagents has not been fully considered and exploited in the literature. The experimental quantification of the Lewis acidity of a small series of diaryliodonium salts was performed using the Gutmann-Beckett method. Validation of a theoretical model using the experimental data was done in order to predict the Lewis acidity of other cationic iodine(III) species. Comparison with known common Lewis acids is presented.

12.
Environ Res ; 156: 747-760, 2017 07.
Article in English | MEDLINE | ID: mdl-28482296

ABSTRACT

INTRODUCTION: Several populations are exposed to mercury (Hg) via their environment, occupation or diet. It is hypothesized that Hg exposure can lead to the development of diabetes mellitus (DM). Metabolic syndrome (MS) is also a possible outcome as its symptoms are closely linked to those of DM. METHOD: We conducted a systematic review of the literature by screening Web of Science, MEDLINE, SciFinder and Embase and we included original studies pertaining to the relationship of total Hg exposure (elemental, inorganic or organic) to DM, MS or insulin resistance. The studies were selected based on the PICOS (patients, intervention, comparator, outcomes and study design) criteria and their quality assessed using a nine-point scale. Study characteristics and results were extracted and presented in structured tables. We also extracted covariates entered as confounding factors to evaluate possible biases in selected studies. Finally, a weight of evidence approach was used to assess the causality of the relationship. RESULTS: A total of 34 studies were included in the present review. Epidemiological data assessment suggests a possible association between total Hg concentrations in different biological matrices and incidence of DM or MS, but the relationship is not consistent. In vivo and in vitro studies support the biological plausibility of the relation between Hg exposure and DM or MS. Five out of nine of Bradford Hill's criteria were fulfilled: strength, temporality, plausibility, coherence and analogy. CONCLUSION: Increased total Hg exposure may augment the risk of DM and MS, but the lack of consistency of the epidemiological evidence prevents inference of a causal relationship. Additional prospective cohort studies and careful consideration of confounding variables and interactions are required to conclude on the causal relationship of total Hg exposure on the development of DM or MS.


Subject(s)
Diabetes Mellitus/epidemiology , Environmental Exposure , Environmental Pollutants , Insulin Resistance , Mercury , Metabolic Syndrome/epidemiology , Animals , Environmental Exposure/adverse effects , Environmental Pollutants/toxicity , Humans , Mercury/toxicity
13.
Br J Clin Pharmacol ; 83(6): 1240-1251, 2017 06.
Article in English | MEDLINE | ID: mdl-28035697

ABSTRACT

AIMS: The aim of this paper is to investigate the role of drug concentration samplings in the modelling of the dose-response relationship. METHODS: Using an initial PK/PD model, a reference dataset was simulated. PK and PD samples were extracted to create reduced datasets. PK/PD and K-PD models were fitted to theses reduced datasets. Post hoc estimates from both types of models were compared to the initial PK/PD model and performance was assessed. RESULTS: K-PD models were largely biased when the drug has a nonlinear elimination. PK/PD models with 1 PK and 2 PD samples were superior to K-PD models with 3 PD samples. PK/PD models with 1 or 2 PK samples and 3 PD samples proved to be superior to K-PD models with 4 PD samples. CONCLUSIONS: K-PD models should not be used when the drug has nonlinear elimination. K-PD models should not replace PK/PD modelling but are an alternative approach if the PD information is large enough.


Subject(s)
Dose-Response Relationship, Drug , Pharmacokinetics , Algorithms , Databases, Factual , Humans , Models, Statistical , Nonlinear Dynamics , Reference Standards , Reproducibility of Results , Software
14.
Article in English | MEDLINE | ID: mdl-27240302

ABSTRACT

Metabolomics is an "omic" technique being increasingly used in epidemiological and clinical studies. We developed a method combining untargeted metabolomics with the quantitative determination of eight amino acids (AA) and eight acylcarnitines (AC) in plasma using ultra-high pressure liquid chromatography (UHPLC), electrospray ionization (ESI) and quadrupole time-of-flight mass spectrometry (QTOFMS). Separation of metabolites is performed by ion-pair reverse phase UHPLC using a HSS T3 column (2.1×100mm, 100Å, 1.8µm particle size) and formic acid-ammonium acetate-heptafluorobutyric acid in water and formic acid-ammonium acetate in methanol as mobile phases. Metabolite identification and quantification are achieved using a QTOFMS operating in ESI-positive and full-scan mode along with MS(E) acquisition of fragmentation patterns. Targeted metabolites are quantified using the appropriate labeled standards and include branched-chain AA (leucine, isoleucine, valine), aromatic AA (phenylalanine, tyrosine) as well as acetylcarnitine and propionylcarnitine, which have been identified as biomarkers of future cardiometabolic disease risk. The inter-day precision (relative standard deviation) for the targeted method was <15% for all but one metabolite and accuracy (bias) of amino acids ranged from 0.5% to 13.9% using SRM 1950 as the external standard. Untargeted metabolomics in 30 plasma samples from the general Canadian population revealed 5018 features, of which 48 metabolites were identified using the MZmine 2.19 software including 23 by our in-house library that comprises 671 annotated metabolites. SRM 1950 analysis revealed 11,684 features, among which 154 metabolites were identified. Our method is currently applied in several epidemiological studies to better characterize cardiometabolic diseases and identify new biomarkers for disease prevention.


Subject(s)
Amino Acids/blood , Carnitine/analogs & derivatives , Chromatography, High Pressure Liquid/methods , Metabolomics/methods , Aged , Amino Acids/metabolism , Biomarkers/blood , Biomarkers/metabolism , Carnitine/blood , Carnitine/metabolism , Female , Humans , Limit of Detection , Male , Middle Aged , Spectrometry, Mass, Electrospray Ionization/methods
15.
AAPS J ; 18(1): 217-27, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26553482

ABSTRACT

The objective of this study was to characterize the baseline circadian rhythm of testosterone levels in hypogonadal men. A total of 859 baseline profiles of testosterone from hypogonadal men were included in this analysis. The circadian rhythm of the testosterone was described by a stretched cosine function. Model parameters were estimated using NONMEM(®) 7.3. The effect of different covariates on the testosterone levels was investigated. Model evaluation was performed using non-parametric bootstrap and predictive checks. A stretched cosine function deeply improved the data goodness of fit compared to the standard trigonometric function (p < 0.001; ΔOFV = -204). The effect of the age and the semester, defined as winter and spring versus summer and fall, were significantly associated with the baseline levels of testosterone (p < 0.001, ΔOFV = -15.6, and p < 0.001, ΔOFV = -47.0). Model evaluation procedures such as diagnostic plots, visual predictive check, and non-parametric bootstrap evidenced that the proposed stretched cosine function was able to model the time course of the diurnal testosterone levels in hypogonadal males with accuracy and precision. The circadian rhythm of the testosterone levels was better predicted by the proposed stretched cosine function than a standard cosine function. Testosterone levels decreased by 5.74 ng/dL (2.4%) every 10 years and were 19.3 ng/dL (8.1%) higher during winter and spring compared to summer and fall.


Subject(s)
Aging/blood , Circadian Rhythm , Hypogonadism/blood , Testosterone/blood , Adult , Aged , Algorithms , Humans , Male , Middle Aged , Models, Statistical , Seasons , Software , Young Adult
16.
Int Rev Psychiatry ; 27(5): 367-85, 2015.
Article in English | MEDLINE | ID: mdl-26552495

ABSTRACT

Many studies, reviews, and meta-analyses have reported elevated mental health problems for sexual minority (SM) individuals. This systematic review provides an update by including numerous recent studies, and explores whether SM individuals are at increased risk across selected mental health problems as per dimensions of sexual orientation (SO), genders, life-stages, geographic regions, and in higher quality studies. A systematic search in PubMed produced 199 studies appropriate for review. A clear majority of studies reported elevated risks for depression, anxiety, suicide attempts or suicides, and substance-related problems for SM men and women, as adolescents or adults from many geographic regions, and with varied SO dimensions (behaviour, attraction, identity), especially in more recent and higher quality studies. One notable exception is alcohol-related problems, where many studies reported zero or reversed effects, especially for SM men. All SM subgroups were at increased risk, but bisexual individuals were at highest risk in the majority of studies. Other subgroup and gender differences are more complex and are discussed. The review supports the long-standing mental health risk proposition for SM individuals, overall and as subgroups.


Subject(s)
Anxiety/epidemiology , Bisexuality/statistics & numerical data , Depression/epidemiology , Homosexuality/statistics & numerical data , Substance-Related Disorders/epidemiology , Suicide/statistics & numerical data , Female , Humans , Male
17.
J Pharmacokinet Pharmacodyn ; 42(3): 287-99, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25895899

ABSTRACT

The objective of this analysis was to characterize the time course of selected pharmacodynamic (PD) markers of tesamorelin: growth hormone (GH) and insulin-like growth factor (IGF-1) concentrations in HIV-infected patients and healthy volunteers. A total of 41 subjects in Phase I trials receiving subcutaneous daily doses of 1 or 2 mg of tesamorelin during 14 consecutive days were included in this analysis. A previous pharmacokinetic (PK) model of tesamorelin was used as the input function for the PD model of GH. Tesamorelin was hypothesized to stimulate the secretion of GH in an "episodic" manner, i.e., for a finite duration of time. The resulting PK/PD model of GH was used to describe the time course of IGF-1. The effect of age, body weight, body mass index, sex, race, and health status on the model parameters was evaluated. The model was qualified using predictive checks and non-parametric bootstrap. Within the range of the values evaluated no covariates were significantly associated with GH or IGF-1 model parameters. Model evaluation procedures indicated accurate prediction of the selected pharmacodynamic markers. The time course of GH and IGF-1 concentrations following multiple doses of tesamorelin were well predicted by the sequential PK/PD model developed using Phase I data.


Subject(s)
Growth Hormone-Releasing Hormone/analogs & derivatives , HIV Infections/metabolism , Models, Biological , Adult , Dose-Response Relationship, Drug , Female , Growth Hormone-Releasing Hormone/pharmacokinetics , Growth Hormone-Releasing Hormone/therapeutic use , HIV Infections/drug therapy , Healthy Volunteers , Human Growth Hormone/metabolism , Humans , Insulin-Like Growth Factor I/metabolism , Male , Middle Aged
18.
Clin Pharmacokinet ; 54(3): 285-94, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25358450

ABSTRACT

BACKGROUND AND OBJECTIVES: Tesamorelin is a synthetic analogue of growth hormone-releasing factor (GRF), which increases basal and pulsatile growth hormone (GH) secretion and subsequently increases insulin-like growth factor (IGF)-1. Limited information is available about the pharmacokinetics of this compound. Consequently, the aim of this study was to characterize the population pharmacokinetics of tesamorelin in HIV-infected patients and healthy subjects. METHODS: A total of 38 HIV-infected patients and healthy subjects receiving subcutaneous tesamorelin doses of 1 or 2 mg administered daily during 14 consecutive days were included in the analysis. An open one-compartment model with first- and zero-order absorption and first-order elimination was developed to best describe the data using NONMEM(®) VII. The effect of different covariates on tesamorelin pharmacokinetics was investigated. Model evaluation was performed using predictive checks and non-parametric bootstrap. RESULTS: Plasma clearance and its interindividual variability [% coefficient of variation (CV)] was estimated to be 1,060 L/h (33.6 %). Volume of distribution was calculated to be 200 L (17.7 %). Age, body size measures, race and health status were not related to tesamorelin pharmacokinetic parameters within the range of covariates studied. The fraction of tesamorelin absorbed by a first-order process is 13.1 % higher on day 14 compared with day 1. Predictive checks and non-parametric bootstrap demonstrated that the model is appropriate in describing the time course of tesamorelin plasma concentrations in both HIV-infected patients and healthy subjects. CONCLUSIONS: An open one-compartment model with first and zero order absorption processes and linear elimination is suitable to characterize the pharmacokinetics of tesamorelin. The fraction of tesamorelin absorbed by a first-order process evolves with time. No clinically relevant covariates were identified as predictors of tesamorelin pharmacokinetics.


Subject(s)
Growth Hormone-Releasing Hormone/analogs & derivatives , HIV Infections/drug therapy , HIV Infections/metabolism , Body Mass Index , Female , Growth Hormone-Releasing Hormone/administration & dosage , Growth Hormone-Releasing Hormone/blood , Growth Hormone-Releasing Hormone/pharmacokinetics , HIV Infections/blood , Humans , Male , Middle Aged
19.
Inorg Chem ; 53(19): 10039-41, 2014 Oct 06.
Article in English | MEDLINE | ID: mdl-25247489

ABSTRACT

A molecular triangle, based on the self-assembly of 4,7-phenanthroline by a neutral palladium complex, has been synthesized and characterized by a combination of techniques: (1)H NMR and UV-vis absorption spectroscopies, mass spectrometry, elemental analysis, and gel permeation chromatography. This new neutral metallocavitand has demonstrated the capacity to host both anionic and cationic guests, thus acting as an open-shaped heteroditopic receptor. Density functional theory calculations have shown that (i) there is no overtension in the assembly of the discrete triangle, which is more stable than open-chain oligomers, (ii) the adducts formed between the triangle and some salts (modeled in the gas phase) are thermodynamically stable, and (iii) two types of cavities coexist in the triangle, which host ions and ion pairs. This easily accessible triangular unit extends further the rational design of model nanoarchitectures in host-guest chemistry with applications in analytical chemistry and multifunctional molecular materials.

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