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Background: APOE4 has broad effects, one of which is worsened cognitive outcomes in cancer survivors following chemotherapy treatment compared to APOE3. Method: 1‐2 month old female APOE3 and APOE4‐Targeted Replacement (TR) mice were used for whole cell patch‐clamp experiments in the entorhinal cortex. Chemotherapy was introduced via a single injection of doxorubicin (10 mg/kg) or saline (control) and treated APOE‐TR mice were euthanized 1 week post‐injection. 0.5% biocytin internal solution was used to visualize cell morphology post hoc under a confocal microscope. Results: Pyramidal cells in the entorhinal cortex of APOE4‐TR mice (4 mice, n = 26 cells) exhibit significantly decreased spontaneous excitatory and inhibitory postsynaptic current frequencies, thereby contributing to an elevated excitatory‐inhibitory balance compared to APOE3‐TR mice (4 mice, n = 23 cells). Doxorubicin‐treated APOE3‐TR mice (4 mice, n = 33 cells) show a significant increase in spontaneous excitatory and inhibitory postsynaptic current amplitudes compared to controls (2 mice, n = 16 cells), while doxorubicin‐treated APOE4‐TR mice (5 mice, n = 20 cells) display no such synaptic changes compared to controls (4 mice, n = 19 cells). Conclusion: APOE4 has baseline effects on entorhinal cortex circuit inhibition and the lack of response to chemotherapy may reflect reduced resilience to stressors. [ABSTRACT FROM AUTHOR]

Patient groups prone to polypharmacy and special subpopulations are susceptible to suboptimal treatment. Refined dosing in special populations is imperative to improve therapeutic response and/or lowering the risk of toxicity. Model-informed precision dosing (MIPD) may improve treatment outcomes by achieving the optimal dose for an individual patient. There is, however, relatively little published evidence of large-scale utility and impact of MIPD, where it is often implemented as local collaborative efforts between academia and healthcare. This article highlights some successful applications of bringing MIPD to clinical care and proposes strategies for wider integration in healthcare. Considerations are brought up herein that will need addressing to see MIPD become 'widespread clinical practice,' among those, wider interdisciplinary collaborations and the necessity for further evidence-based efficacy and cost-benefit analysis of MIPD in healthcare. The implications of MIPD on regulatory policies and pharmaceutical development are also discussed as part of the roadmap. [ABSTRACT FROM AUTHOR]

High throughput molecular and functional profiling of patients is a key driver of precision medicine. DNA and RNA characterization has been enabled at unprecedented cost and scale through rapid, disruptive progress in sequencing technology, but challenges persist in data management and interpretation. We analyze the state-of-the-art of large-scale unbiased sequencing in drug discovery and development, including technology, application, ethical, regulatory, policy and commercial considerations, and discuss issues of LUS implementation in clinical and regulatory practice. [ABSTRACT FROM AUTHOR]

A number of therapeutics have been developed or are under development aiming to modulate the coagulation network to treat various diseases. We used a systems model to better understand the effect of modulating various components on blood coagulation. A computational model of the coagulation network was built to match in-house in vitro thrombin generation and activated Partial Thromboplastin Time (aPTT) data with various concentrations of recombinant factor VIIa (FVIIa) or factor Xa added to normal human plasma or factor VIII-deficient plasma. Sensitivity analysis applied to the model revealed that lag time, peak thrombin concentration, area under the curve (AUC) of the thrombin generation profile, and aPTT show different sensitivity to changes in coagulation factors' concentrations and type of plasma used (normal or factor VIII-deficient). We also used the model to explore how variability in concentrations of the proteins in coagulation network can impact the response to FVIIa treatment. [ABSTRACT FROM AUTHOR]

Background and Purpose The Eph receptor tyrosine kinases and their ephrin ligands are key players in tumorigenesis and many reports have correlated changes in their expression with a poor clinical prognosis in many solid tumours. Agents targeting the Eph-ephrin system might emerge as new tools useful for the inhibition of different components of cancer progression. Even if different classes of small molecules targeting Eph-ephrin interactions have been reported, their use is hampered by poor chemical stability and low potency. Stable and potent ligands are crucial to achieve robust pharmacological performance. Experimental Approach Uni PR129 (the L-homo- Trp conjugate of lithocholic acid) was designed by means of computational methods, synthetized and tested for its ability to inhibit the interaction between the Eph A2 receptor and the ephrin- A1 ligand in an elisa binding study. The ability of Uni PR129 to disrupt Eph A2-ephrin- A1 interaction was functionally evaluated in a prostate adenocarcinoma cell line and its anti-angiogenic effect was tested in vitro using cultures of HUVECs. Key Results Uni PR129 disrupted Eph A2-ephrin- A1 interaction with Ki = 370 nM in an elisa binding assay and with low micromolar potency in cellular functional assays, including inhibition of Eph A2 activation, inhibition of PC3 cell rounding and disruption of in vitro angiogenesis, without cytotoxic effects. Conclusions and Implications The discovery of Uni PR129 represents not only a major advance in potency compared with the existing Eph-ephrin antagonists but also an improvement in terms of cytotoxicity, making this molecule a useful pharmacological tool and a promising lead compound. [ABSTRACT FROM AUTHOR]

Background and Purpose: The Eph receptor tyrosine kinases and their ephrin ligands are key players in tumorigenesis and many reports have correlated changes in their expression with a poor clinical prognosis in many solid tumours. Agents targeting the Eph-ephrin system might emerge as new tools useful for the inhibition of different components of cancer progression. Even if different classes of small molecules targeting Eph-ephrin interactions have been reported, their use is hampered by poor chemical stability and low potency. Stable and potent ligands are crucial to achieve robust pharmacological performance.Experimental Approach: UniPR129 (the L-homo-Trp conjugate of lithocholic acid) was designed by means of computational methods, synthetized and tested for its ability to inhibit the interaction between the EphA2 receptor and the ephrin-A1 ligand in an elisa binding study. The ability of UniPR129 to disrupt EphA2-ephrin-A1 interaction was functionally evaluated in a prostate adenocarcinoma cell line and its anti-angiogenic effect was tested in vitro using cultures of HUVECs.Key Results: UniPR129 disrupted EphA2-ephrin-A1 interaction with Ki = 370 nM in an elisa binding assay and with low micromolar potency in cellular functional assays, including inhibition of EphA2 activation, inhibition of PC3 cell rounding and disruption of in vitro angiogenesis, without cytotoxic effects.Conclusions and Implications: The discovery of UniPR129 represents not only a major advance in potency compared with the existing Eph-ephrin antagonists but also an improvement in terms of cytotoxicity, making this molecule a useful pharmacological tool and a promising lead compound. [ABSTRACT FROM AUTHOR]

A commentary on "Enhancing Value of Clinical Pharmacodynamics in Oncology Drug Development: An Alliance Between Quantitative Pharmacology and Translational Science" which was published in the previous issue of the periodical is presented. It mentions important modern considerations for pharmacodynamic (PD) evaluation in oncology. The article adds the determination of the optimal biologic dose (OBD) along with the challenges of collecting paired tumor biopsies.

The theme of this month's issue of Clinical Pharmacology & Therapeutics is pharmacometrics. When looking back at the early days of pharmacometrics, current contributions to the drug development process look impressive. The questions are whether the original promise is being kept and how the impact can become even greater. [ABSTRACT FROM AUTHOR]

Objective To compare magnesium sulphate concentrations achieved by intramuscular and intravenous regimens used for the prevention of eclampsia. Setting Low-resource obstetric hospitals in Nagpur and Vellore, India. Population Pregnant women at risk for eclampsia due to hypertensive disease. Methods A pharmacokinetic study was performed as part of a randomised trial that enrolled 300 women comparing intramuscular and intravenous maintenance regimens of magnesium dosing. Data from 258 enrolled women were analysed in the pharmacokinetic study. A single sample was drawn per woman with the expectation of using samples in a pooled data analysis. Main outcome measures Pharmacokinetic parameters of magnesium distribution and clearance. Results Magnesium clearance was estimated to be 48.1 dl/hour, volume of distribution to be 156 dl and intramuscular bioavailability to be 86.2%. The intramuscular regimen produced higher initial serum concentrations, consistent with a substantially larger loading dose. At steady state, magnesium concentrations in the intramuscular and intravenous groups were comparable. With either regimen, a substantial number of women would be expected to have serum concentrations lower than those generally held to be therapeutic. Conclusions Clinical implications were that a larger loading dose for the intravenous regimen should be considered; where feasible, individualised dosing of magnesium sulphate would reduce the variability in serum concentrations and might result in more women with clinically effective magnesium concentrations; and lower dose magnesium suphate regimens should be considered with caution. [ABSTRACT FROM AUTHOR]

Modeling and simulation (M&S) is a diverse discipline that uses tools from mathematics, statistics, and computer science to arrive at quantitative predictions. Its application to biological systems has a checkered history with respect to success and failure. The instances of failure may reflect the heterogeneity of M&S approaches. In order to ensure a successful outcome, M&S must be fit for purpose and responsive; connecting with biological concepts is critical; sharing of results has to be done properly; buy-in is achieved in stages. These concepts are being applied in drug discovery and development and are yielding success. However, bottlenecks remain. [ABSTRACT FROM AUTHOR]

Several reports have demonstrated that the efficacy of latanoprost is influenced by the time of dosing. This model-based meta-analysis validates previous findings that evening dosing is superior to morning dosing and predicts the optimal time for dosing, based on the quantitative assessment of baseline and latanoprost-treated 24-h circadian intraocular pressure (IOP) curves. The results confirm the importance of the time of dosing as a factor that influences the extent of reduction in IOP and underline the need to take this factor into consideration in the design of glaucoma trials and therapy. [ABSTRACT FROM AUTHOR]

The purpose of this commentary is to place probability of trial success, or assurance, in the context of decision making in drug development, and to illustrate its properties in an intuitive manner for the readers of Clinical Pharmacology and Therapeutics. The hope is that this will stimulate a dialog on how assurance should be incorporated into a quantitative decision approach for clinical development and trial design that uses all available information. [ABSTRACT FROM AUTHOR]

This study investigates the efficacy and safety of personalized cyclophosphamide (CY) dosing in 50 patients receiving CY along with total body irradiation (TBI). Participants received CY 45 mg/kg with subsequent therapeutic drug monitoring using Bayesian parameter estimation to personalize the second CY dose to a target area under the curve (AUC) for carboxyethylphosphoramide mustard (CEPM) (a reporter molecule for CY-derived toxins) and for hydroxycyclophosphamide (to ensure engraftment). The mean second CY dose was 66 mg/kg; the total dose ranged from 45 to 145 mg/kg. After completion of this phase II study, we compared participants' clinical outcomes with those of concurrent controls (n = 100) who received TBI along with standard CY doses of 120 mg/kg. Patients receiving personalized CY dosing had significantly lower postconditioning peak total serum bilirubin (P = 0.03); a 38% reduction in the hazard of acute kidney injury (AKI) (P = 0.03); and nonrelapse and overall survival rates similar to those in the controls (P = 0.70 and 0.63, respectively) despite the lower doses of CY administered to most of the patients in the personalized dosage group.Clinical Pharmacology & Therapeutics (2009); 85, 6, 615–622 doi:10.1038/clpt.2009.27 [ABSTRACT FROM AUTHOR]

Glyburide's pharmacokinetics (PK) and pharmacodynamics have not been studied in women with gestational diabetes mellitus (GDM). The objective of this study was to assess steady-state PK of glyburide, as well as insulin sensitivity, β-cell responsivity, and overall disposition indices after a mixed-meal tolerance test (MMTT) in women with GDM (n = 40), nonpregnant women with type 2 diabetes mellitus (T2DM) (n = 26), and healthy pregnant women (n = 40, MMTT only). At equivalent doses, glyburide plasma concentrations were ~50% lower in pregnant women than in nonpregnant subjects. The average umbilical cord/maternal plasma glyburide concentration ratio at the time of delivery was 0.7 ± 0.4. Insulin sensitivity was approximately fivefold lower in women with GDM as compared with healthy pregnant women. Despite comparable β-cell responsivity indices, the average β-cell function corrected for insulin resistance was more than 3.5-fold lower in women with glyburide-treated GDM than in healthy pregnant women. Women with GDM in whom glyburide treatment has failed may benefit from alternative medication or dosage escalation; however, fetal safety should be kept in mind.Clinical Pharmacology & Therapeutics (2009); 85, 6, 607–614 doi:10.1038/clpt.2009.5 [ABSTRACT FROM AUTHOR]

Cyclophosphamide-based regimens are front-line treatment for numerous pediatric malignancies; however, current dosing methods result in considerable interpatient variability in tumor response and toxicity. In this pediatric population, the authors' objectives were (1) to quantify and explain the pharmacokinetic variability of cyclophosphamide and 2 of its metabolites, hydroxycyclophosphamide (HCY) and carboxyethylphosphoramide mustard (CEPM), and (2) to apply a population pharmacokinetic model to describe the disposition of cyclophosphamide and these metabolites. A total of 196 blood samples were obtained from 22 children with neuroblastoma receiving intravenous cyclophosphamide (400 mg/m[2]/d) and topotecan. Blood samples were quantitated for concentrations of cyclophosphamide, HCY, and CEPM using liquid chromatography-mass spectrometry and analyzed using nonlinear mixed-effects modeling with the NONMEM software system. After model building was complete, the area under the concentration-time curve (AUC) was computed using NONMEM. Cyclophosphamide elimination was described by noninducible and inducible routes, with the latter producing HCY. Glomerular filtration rate was a covariate for the fractional elimination of HCY and its conversion to CEPM. Considerable interpatient variability was observed in the AUC of cyclophosphamide, HCY, and CEPM. These results represent a critical first step in developing pharmacokinetic-linked pharmacodynamic studies in children receiving cyclophosphamide to determine the clinical relevance of the pharmacokinetic variability in cyclophosphamide and its metabolites. [ABSTRACT FROM AUTHOR]

The article discusses the morphological analysis of paper images through scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The materials are segmented into individual fibers to determine their digital measurements using secondary electron detector. Calcium carbonate particles resulted to the formation of fillers characterized by large amounts of coarse edge fibers and irregular granules. Furthermore, fiber borders with small size width are accidentally identified, however, they represent flat and peak directions.

Amoxicillin is recommended for anthrax prevention in pregnancy. The objective of this study was to evaluate the pharmacokinetics of amoxicillin during pregnancy and postpartum (PP). Sixteen women received amoxicillin during gestation (18–22 weeks (T2) and 30–34 weeks (T3)) as well as 3 months postpartum (PP) to evaluate single-dose pharmacokinetics. Amoxicillin compartmental pharmacokinetic parameters were used to simulate amoxicillin concentration–time profiles following different dosage strategies. Amoxicillin CLrenal (T2: 24.8±6.7 l/h, P<0.001; T3: 24.0±3.9 l/h, P<0.001; and PP: 15.3±2.6 l/h) and renal CLsecretion (T2: 280±105 ml/min, P<0.002; T3: 259±54 ml/min, P<0.001; and PP: 167±47 ml/min) were higher during pregnancy than postpartum. Simulations suggest that amoxicillin concentrations adequate to prevent anthrax may be difficult to achieve during pregnancy and postpartum. Increases in amoxicillin CLrenal and renal CLsecretion reflect increases in filtration and secretory transport or diminished reabsorption in the kidneys. Amoxicillin may not be an appropriate antibiotic for post-anthrax exposure prophylaxis.Clinical Pharmacology & Therapeutics (2007) 81, 547–556. doi:10.1038/sj.clpt.6100126; published online 28 February 2007. [ABSTRACT FROM AUTHOR]

Systems pharmacology is an emerging approach that sets out to use quantitative concepts rooted in the synergy between modeling and simulation on one hand and large-scale data collection and analysis on the other to investigate biological systems and design therapeutic interventions. Interest in this field has recently increased substantially, but so have perceived challenges and misunderstandings, especially related to implementation. This Commentary explores the opportunities and challenges in the rapidly evolving area of systems pharmacology from a drug discovery and development perspective. [ABSTRACT FROM AUTHOR]

Objective: To compare magnesium sulphate concentrations achieved by intramuscular and intravenous regimens used for the prevention of eclampsia., Setting: Low-resource obstetric hospitals in Nagpur and Vellore, India., Population: Pregnant women at risk for eclampsia due to hypertensive disease., Methods: A pharmacokinetic study was performed as part of a randomised trial that enrolled 300 women comparing intramuscular and intravenous maintenance regimens of magnesium dosing. Data from 258 enrolled women were analysed in the pharmacokinetic study. A single sample was drawn per woman with the expectation of using samples in a pooled data analysis., Main Outcome Measures: Pharmacokinetic parameters of magnesium distribution and clearance., Results: Magnesium clearance was estimated to be 48.1 dl/hour, volume of distribution to be 156 dl and intramuscular bioavailability to be 86.2%. The intramuscular regimen produced higher initial serum concentrations, consistent with a substantially larger loading dose. At steady state, magnesium concentrations in the intramuscular and intravenous groups were comparable. With either regimen, a substantial number of women would be expected to have serum concentrations lower than those generally held to be therapeutic., Conclusions: Clinical implications were that a larger loading dose for the intravenous regimen should be considered; where feasible, individualised dosing of magnesium sulphate would reduce the variability in serum concentrations and might result in more women with clinically effective magnesium concentrations; and lower dose magnesium sulphate regimens should be considered with caution., (© 2013 The Authors BJOG An International Journal of Obstetrics and Gynaecology © 2013 RCOG.)

Physiological changes during pregnancy may alter drug pharmacokinetics. Therefore, mechanistic understanding of these changes and, ultimately, clinical studies in pregnant women are necessary to determine if and how dosing regimens should be adjusted. Because of the typically limited number of patients who can be recruited in this patient group, efficient design and analysis of these studies is of special relevance. This paper is a summary of a conference session organized at the American Conference of Pharmacometrics in April 2011, around the topic of applying pharmacometric methodology to this important problem. The discussion included both design and analysis of clinical studies during pregnancy and in silico predictions. An overview of different pharmacometric methods relevant to this subject was given. The impact of pharmacometrics was illustrated using a range of case examples of studies around pregnancy., (© 2012 The Authors. British Journal of Clinical Pharmacology © 2012 The British Pharmacological Society.)

In the title compound, C(19)H(12)Cl(2)N(2)O(5)S(3), the benzene rings of the chloro-phenyl-sulfonyl groups form a dihedral angle of 35.85 (8)° and are inclined at angles of 23.51 (6) and 59.22 (6)° with respect to the essentially planar benzisothia-zole ring system [maximum deviation = 0.030 (2) Å]. The mol-ecular conformation is stabilized by an intra-molecular C-H⋯O hydrogen bond. In the crystal packing, mol-ecules are linked into chains parallel to the a axis by inter-molecular C-H⋯O hydrogen bonds and π-π stacking inter-actions, with centroid-centroid distances of 3.592 (5) Å.

In the title mol-ecule, C(14)H(12)N(2)O(3)S(2), the benzisothia-zolone ring system is essentially planar and forms a dihedral angle of 67.37 (6)° with the plane of the benzene ring. In the crystal structure, mol-ecules are linked via inter-molecular N-H⋯O and C-H⋯O hydrogen bonds to form chains parallel to the b axis.