58 results on '"Alex Phipps"'
Search Results
2. Entrectinib dose confirmation in pediatric oncology patients: pharmacokinetic considerations
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Georgina Meneses-Lorente, Elena Guerini, Francois Mercier, Neil Parrott, Karey Kowalski, Edna Chow-Maneval, Vincent Buchheit, Guillaume Bergthold, Elizabeth Fox, Alex Phipps, and Nassim Djebli
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Pharmacology ,Cancer Research ,Oncology ,Pharmacology (medical) ,Toxicology - Abstract
Purpose Entrectinib is a central nervous system-active potent inhibitor of tropomyosin receptor kinase (TRK), with anti-tumor activity against neurotrophic NTRK gene fusion-positive tumors. This study investigates the pharmacokinetics of entrectinib and its active metabolite (M5) in pediatric patients and aims to understand whether the pediatric dose of 300 mg/m2 once daily (QD) provides an exposure that is consistent with the approved adult dose (600 mg QD). Methods Forty-three patients aged from birth to 22 years were administered entrectinib (250–750 mg/m2 QD) orally with food in 4-week cycles. Entrectinib formulations included capsules without acidulant (F1) and capsules with acidulant (F2B and F06). Results Although there was interpatient variability with F1, entrectinib and M5 exposures increased dose dependently. Lower systemic exposures were observed in pediatric patients receiving 400 mg/m2 QD entrectinib (F1) versus adults receiving either the same dose/formulation or the recommended flat dose of 600 mg QD (~ 300 mg/m2 for a 70 kg adult) due to suboptimal F1 performance in the pediatric study. The observed pediatric exposures following 300 mg/m2 QD entrectinib (F06) were comparable to those in adults receiving 600 mg QD. Conclusions Overall, the F1 formulation of entrectinib was associated with lower systemic exposure in pediatric patients compared with the commercial acidulant formulation (F06). Systemic exposures achieved in pediatric patients with the F06 recommended dose (300 mg/m2) were within the known efficacious range in adults, confirming the adequacy of the recommended dose regimen with the commercial formulation.
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- 2023
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3. The potential and pitfalls of artificial intelligence in clinical pharmacology
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Martin Johnson, Mishal Patel, Alex Phipps, Mihaela van der Schaar, Dave Boulton, and Megan Gibbs
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Modeling and Simulation ,Pharmacology (medical) - Published
- 2023
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4. A Consideration of Fixed Dosing Versus Body Size‐Based Dosing Strategies for Chimeric Antigen Receptor T‐Cell Therapies
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Jimmy Zhijian, He, Hechuan, Wang, KyoungSoo, Lim, Song, Ren, Fred, Rollins, Markus, Vallaster, Ryan, Wong, Richard, Stebbings, Nathan, Standifer, Robert, Keefe, Alex, Phipps, and Megan, Gibbs
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Receptors, Chimeric Antigen ,T-Lymphocytes ,Body Size ,Humans ,Pharmaceutical Science ,Pharmacology (medical) ,Immunotherapy, Adoptive - Published
- 2022
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5. Population Pharmacokinetics of Monalizumab in Patients With Advanced Solid Tumors
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Michael Hwang, Chunling Fan, Mun Sang Yue, Diansong Zhou, Carine Paturel, Pascale Andre, Lin‐Yang Cheng, Patrick Mitchell, Panagiotis Kourtesis, Dario Ruscica, Mayukh Das, Nassim Morsli, Song Ren, Megan Gibbs, Alex Phipps, and Xuyang Song
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Pharmacology ,Pharmacology (medical) - Published
- 2023
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6. Supplemental legend from Prediction of the Optimal Dosing Regimen Using a Mathematical Model of Tumor Uptake for Immunocytokine-Based Cancer Immunotherapy
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Volker Teichgräber, Pavel Pisa, Alex Phipps, Jean Eric Charoin, Jean Tessier, Christian Klein, Stefan Evers, Jehad Charo, Hans Peter Grimm, Tapan Nayak, Christophe Boetsch, and Benjamin Ribba
- Abstract
Supplemental legend
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- 2023
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7. Figure S1 from Prediction of the Optimal Dosing Regimen Using a Mathematical Model of Tumor Uptake for Immunocytokine-Based Cancer Immunotherapy
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Volker Teichgräber, Pavel Pisa, Alex Phipps, Jean Eric Charoin, Jean Tessier, Christian Klein, Stefan Evers, Jehad Charo, Hans Peter Grimm, Tapan Nayak, Christophe Boetsch, and Benjamin Ribba
- Abstract
Supplementary Figure S1: Left: CEA expression by immuno-histochemistry in the LS174T tumor mouse model: homogeneous cytoplasmic antigen distribution. Right: CEA expression in one of the treated patients (colorectal cancer): heterogeneous cytoplasmic antigen distribution with polarized apical accumulation.
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- 2023
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8. Data from Prediction of the Optimal Dosing Regimen Using a Mathematical Model of Tumor Uptake for Immunocytokine-Based Cancer Immunotherapy
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Volker Teichgräber, Pavel Pisa, Alex Phipps, Jean Eric Charoin, Jean Tessier, Christian Klein, Stefan Evers, Jehad Charo, Hans Peter Grimm, Tapan Nayak, Christophe Boetsch, and Benjamin Ribba
- Abstract
Purpose: Optimal dosing is critical for immunocytokine-based cancer immunotherapy to maximize efficacy and minimize toxicity. Cergutuzumab amunaleukin (CEA-IL2v) is a novel CEA-targeted immunocytokine. We set out to develop a mathematical model to predict intratumoral CEA-IL2v concentrations following various systemic dosing intensities.Experimental Design: Sequential measurements of CEA-IL2v plasma concentrations in 74 patients with solid tumors were applied in a series of differential equations to devise a model that also incorporates the peripheral concentrations of IL2 receptor–positive cell populations (i.e., CD8+, CD4+, NK, and B cells), which affect tumor bioavailability of CEA-IL2v. Imaging data from a subset of 14 patients were subsequently utilized to additionally predict antibody uptake in tumor tissues.Results: We created a pharmacokinetic/pharmacodynamic mathematical model that incorporates the expansion of IL2R-positive target cells at multiple dose levels and different schedules of CEA-IL2v. Model-based prediction of drug levels correlated with the concentration of IL2R-positive cells in the peripheral blood of patients. The pharmacokinetic model was further refined and extended by adding a model of antibody uptake, which is based on drug dose and the biological properties of the tumor. In silico predictions of our model correlated with imaging data and demonstrated that a dose-dense schedule comprising escalating doses and shortened intervals of drug administration can improve intratumoral drug uptake and overcome consumption of CEA-IL2v by the expanding population of IL2R-positive cells.Conclusions: The model presented here allows simulation of individualized treatment plans for optimal dosing and scheduling of immunocytokines for anticancer immunotherapy. Clin Cancer Res; 24(14); 3325–33. ©2018 AACR.See related commentary by Ruiz-Cerdá et al., p. 3236
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- 2023
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9. Figure S3 from Prediction of the Optimal Dosing Regimen Using a Mathematical Model of Tumor Uptake for Immunocytokine-Based Cancer Immunotherapy
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Volker Teichgräber, Pavel Pisa, Alex Phipps, Jean Eric Charoin, Jean Tessier, Christian Klein, Stefan Evers, Jehad Charo, Hans Peter Grimm, Tapan Nayak, Christophe Boetsch, and Benjamin Ribba
- Abstract
Supplementary Figure S3: Comparison of QW versus Q2W CEA-IL2v dosing schedule. Top panel: Predicted pharmacokinetic population profile from cycle 1 to 4 at 20 mg QW (left); Predicted corresponding tumor uptake (right). Bottom panel: same two graphics for Q2W schedule (pharmacokinetic - left, and tumor uptake - right).
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- 2023
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10. Table S2 from Prediction of the Optimal Dosing Regimen Using a Mathematical Model of Tumor Uptake for Immunocytokine-Based Cancer Immunotherapy
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Volker Teichgräber, Pavel Pisa, Alex Phipps, Jean Eric Charoin, Jean Tessier, Christian Klein, Stefan Evers, Jehad Charo, Hans Peter Grimm, Tapan Nayak, Christophe Boetsch, and Benjamin Ribba
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Supplemental Table S2: Model parameter estimates. For model equations, refer to supplemental material.
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- 2023
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11. Table S1 from Prediction of the Optimal Dosing Regimen Using a Mathematical Model of Tumor Uptake for Immunocytokine-Based Cancer Immunotherapy
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Volker Teichgräber, Pavel Pisa, Alex Phipps, Jean Eric Charoin, Jean Tessier, Christian Klein, Stefan Evers, Jehad Charo, Hans Peter Grimm, Tapan Nayak, Christophe Boetsch, and Benjamin Ribba
- Abstract
Supplementary Table S1: Characteristics in terms of CEA status, dose received and cancer indication of the 14 patients from the functional imaging study.
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- 2023
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12. Figure S2 from Prediction of the Optimal Dosing Regimen Using a Mathematical Model of Tumor Uptake for Immunocytokine-Based Cancer Immunotherapy
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Volker Teichgräber, Pavel Pisa, Alex Phipps, Jean Eric Charoin, Jean Tessier, Christian Klein, Stefan Evers, Jehad Charo, Hans Peter Grimm, Tapan Nayak, Christophe Boetsch, and Benjamin Ribba
- Abstract
Supplementary Figure S2: Values of the estimated uptake ratio of the expected extravasation/penetration parameter from [8] based on LST174 data across indications in the 8 CEA+ patients.
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- 2023
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13. Physiologically-Based Pharmacokinetic Modelling of Entrectinib Parent and Active Metabolite to Support Regulatory Decision-Making
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Li Yu, Elena Guerini, Georgina Meneses-Lorente, Alex Phipps, Vincent Buchheit, Nassim Djebli, Francois Mercier, Yumi Cleary, Stephen Fowler, Nicolas Frey, and Neil Parrott
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Pharmacology ,Physiologically based pharmacokinetic modelling ,Indazoles ,Efavirenz ,CYP3A4 ,Cytochrome P-450 CYP3A Inducers ,Entrectinib ,Carbamazepine ,chemistry.chemical_compound ,chemistry ,Pharmacokinetics ,Benzamides ,medicine ,Cytochrome P-450 CYP3A Inhibitors ,Humans ,Computer Simulation ,Drug Interactions ,Pharmacology (medical) ,Dosing ,Active metabolite ,medicine.drug - Abstract
Entrectinib is a selective inhibitor of ROS1/TRK/ALK kinases, recently approved for oncology indications. Entrectinib is predominantly cleared by cytochrome P450 (CYP) 3A4, and modulation of CYP3A enzyme activity profoundly alters the pharmacokinetics of both entrectinib and its active metabolite M5. We describe development of a combined physiologically based pharmacokinetic (PBPK) model for entrectinib and M5 to support dosing recommendations when entrectinib is co-administered with CYP3A4 inhibitors or inducers. A PBPK model was established in Simcyp® Simulator. The initial model based on in vitro–in vivo extrapolation was refined using sensitivity analysis and non-linear mixed effects modeling to optimize parameter estimates and to improve model fit to data from a clinical drug–drug interaction study with the strong CYP3A4 inhibitor, itraconazole. The model was subsequently qualified against clinical data, and the final qualified model used to simulate the effects of moderate to strong CYP3A4 inhibitors and inducers on entrectinib and M5 pharmacokinetics. The final model showed good predictive performance for entrectinib and M5, meeting commonly used predictive performance acceptance criteria in each case. The model predicted that co-administration of various moderate CYP3A4 inhibitors (verapamil, erythromycin, clarithromycin, fluconazole, and diltiazem) would result in an average increase in entrectinib exposure between 2.2- and 3.1-fold, with corresponding average increases for M5 of approximately 2-fold. Co-administration of moderate CYP3A4 inducers (efavirenz, carbamazepine, phenytoin) was predicted to result in an average decrease in entrectinib exposure between 45 and 79%, with corresponding average decreases for M5 of approximately 50%. The model simulations were used to derive dosing recommendations for co-administering entrectinib with CYP3A4 inhibitors or inducers. PBPK modeling has been used in lieu of clinical studies to enable regulatory decision-making.
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- 2021
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14. Characterization of the pharmacokinetics of entrectinib and its active M5 metabolite in healthy volunteers and patients with solid tumors
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Darren Bentley, Nassim Djebli, Andreas Brink, Edna Chow-Maneval, Elena Guerini, Karey Kowalski, Vincent Buchheit, Francois Mercier, Georgina Meneses-Lorente, Alex Phipps, and Li Yu
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Adult ,Male ,0301 basic medicine ,Indazoles ,Metabolite ,ADME Study ,Antineoplastic Agents ,Capsules ,Entrectinib ,Pharmacology ,Bioequivalence ,Feces ,Food-Drug Interactions ,Young Adult ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Pharmacokinetics ,Neoplasms ,Phase I Studies ,Humans ,Distribution (pharmacology) ,Medicine ,Pharmacology (medical) ,Protein Kinase Inhibitors ,Active metabolite ,Aged ,ADME ,Cross-Over Studies ,business.industry ,Fasting ,Middle Aged ,Food effect ,Healthy Volunteers ,030104 developmental biology ,Therapeutic Equivalency ,Oncology ,chemistry ,030220 oncology & carcinogenesis ,Benzamides ,Female ,business ,TRK/ROS1/ALK - Abstract
SummaryBackground: Entrectinib is an oral, CNS-active, potent inhibitor of tyrosine receptor kinases A/B/C, tyrosine kinase ROS proto-oncogene 1, and anaplastic lymphoma kinase approved for use in patients with solid tumors. We describe 3 clinical studies, including one investigating the single/multiple dose pharmacokinetics of entrectinib in patients and two studies in healthy volunteers investigating the absorption/distribution/metabolism/excretion (ADME) of entrectinib, its relative bioavailability, and effect of food on pharmacokinetics. Methods: The patient study is open-label with dose-escalation and expansion phases. Volunteers received entrectinib (100–400 mg/m2, and 600–800 mg) once daily with food in continuous 28-day cycles. In the ADME study, volunteers received a single oral dose of [14C]entrectinib 600 mg. In the third study, volunteers received single doses of entrectinib 600 mg as the research and marketed formulations in the fasted state (Part 1), and the marketed formulation in the fed and fasted states (Part 2). Entrectinib and its major active metabolite M5 were assessed in all studies. Results: Entrectinib was absorbed in a dose-dependent manner with maximum concentrations at ~4 h postdose and an elimination half-life of ~20 h. Entrectinib was cleared mainly through metabolism and both entrectinib and metabolites were eliminated mainly in feces (minimal renal excretion). At steady-state, the M5-to-entrectinib AUC ratio was 0.5 (with 600 mg entrectinib research formulation in patients). The research and marketed formulations were bioequivalent and food had no relevant effect on pharmacokinetics. Conclusions: Entrectinib is well absorbed, with linear PK that is suitable for once-daily dosing, and can be taken with or without food.
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- 2021
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15. From waterfall plots to spaghetti plots in early oncology clinical development
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Benjamin Ribba, Nicola Consalvo, Alex Phipps, Francois Mercier, and Nicolas Frey
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Statistics and Probability ,Oncology ,medicine.medical_specialty ,Time Factors ,Tumor burden ,Waterfall ,Drug Development ,Spaghetti plot ,Neoplasms ,Internal medicine ,medicine ,Humans ,Pharmacology (medical) ,Baseline (configuration management) ,Mathematics ,Pharmacology ,Clinical Trials as Topic ,geography ,geography.geographical_feature_category ,Tumor size ,Confounding ,Tumor Burden ,Treatment Outcome ,Research Design ,Data Interpretation, Statistical ,Time dynamics ,Radar chart - Abstract
Waterfall plots are used to describe changes in tumor size observed in clinical studies. They are frequently used to illustrate the overall drug response in oncology clinical trials because of its simple representation of results. Unfortunately, this visual display suffers a number of limitations including (1) potential misguidance by masking the time dynamics of tumor size, (2) ambiguous labelling of the y-axis, and (3) low data-to-ink ratio. We offer some alternatives to address these shortcomings and recommend moving away from waterfall plots to the benefit of plots showing the individual time profiles of sum of lesion diameters (according to RECIST). The spider plot presents the individual changes in tumor measurements over time relative to baseline tumor burden. Baseline tumor size is a well-known confounding factor of drug effect which has to be accounted for when analyzing data in early clinical trials. While spider plots are conveniently correct for baseline tumor size, they cannot be presented in isolation. Indeed, percentage change from baseline has suboptimal statistical properties (including skewed distribution) and can be overly optimistic in favor of drug efficacy. We argued that plots of raw data (referred to as spaghetti plots) should always accompany spider plots to provide an equipoised illustration of the drug effect on lesion diameters.
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- 2019
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16. Case report of a fatal rectal haemorrhage in a person with severe haemophilia A receiving emicizumab and high‐dose bypassing agents in the HAVEN 1 study
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Michael Pidcock, Tiffany Chang, Geoffrey Kershaw, Liane Khoo, Alex Phipps, Anna Kiialainen, and Stephen Matthews
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Emicizumab ,Pediatrics ,medicine.medical_specialty ,business.industry ,Rectal haemorrhage ,MEDLINE ,Medicine ,Severe haemophilia A ,Hematology ,General Medicine ,business ,Genetics (clinical) - Published
- 2020
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17. PK/PD Mediated Dose Optimization of Emactuzumab, a CSF1R Inhibitor, in Patients With Advanced Solid Tumors and Diffuse-Type Tenosynovial Giant Cell Tumor
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Dominik Rüttinger, Carola Ries, Ann-Marie E Bröske, Georgina Meneses-Lorente, Claudia Mueller, Alex Phipps, Kevin Smart, Monika Baehner, Michael A. Cannarile, and Antje-Christine Walz
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medicine.drug_class ,Cell ,Emactuzumab ,Giant Cell Tumor of Tendon Sheath ,Pharmacology ,Monoclonal antibody ,Antibodies, Monoclonal, Humanized ,030226 pharmacology & pharmacy ,Models, Biological ,Drug Administration Schedule ,Article ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,Antineoplastic Agents, Immunological ,law ,Medicine ,Humans ,Pharmacology (medical) ,Drug Dosage Calculations ,Dosing ,Molecular Targeted Therapy ,Receptor ,PK/PD models ,Clinical pharmacology ,Clinical Trials, Phase I as Topic ,business.industry ,Research ,Articles ,medicine.anatomical_structure ,Treatment Outcome ,Receptors, Granulocyte-Macrophage Colony-Stimulating Factor ,030220 oncology & carcinogenesis ,Pharmacodynamics ,business ,Signal Transduction - Abstract
Targeted biological therapies may achieve maximal therapeutic efficacy at doses below the maximum tolerated dose (MTD); therefore, the search for the MTD in clinical studies may not be ideal for these agents. Emactuzumab is an investigational monoclonal antibody that binds to and inhibits the activation of the cell surface colony-stimulating factor-1 receptor. Here, we show how modeling target-mediated drug disposition coupled with pharmacodynamic end points was used to optimize the dose of emactuzumab without defining an MTD. The model could be used to recommend doses across different disease indications. The approach recommended an optimal biological dose of emactuzumab for dosing every 2 weeks (q2w) ≥ 900 mg, approximately three-fold lower than the highest dose tested clinically. The model predicted that emactuzumab doses ≥ 900 mg q2w would achieve target saturation in excess of 90% over the entire dosing cycle. Subsequently, a dose of 1,000 mg q2w was used in the extension phase of a phase I study of emactuzumab in patients with advanced solid tumors or diffuse-type tenosynovial giant cell tumor. Clinical data from this study were consistent with model predictions. The model was also used to predict the optimum dose of emactuzumab for use with dosing every 3 weeks, enabling dosing flexibility with respect to comedications. In summary, this work demonstrates the value of quantitative clinical pharmacology approaches to dose selection in oncology as opposed to traditional MTD methods.
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- 2020
18. Prediction of the Optimal Dosing Regimen Using a Mathematical Model of Tumor Uptake for Immunocytokine-Based Cancer Immunotherapy
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Jean Tessier, Jean Eric Charoin, Christian Klein, Jehad Charo, Pavel Pisa, Alex Phipps, Hans Peter Grimm, Tapan K. Nayak, Volker Teichgräber, Stefan Evers, Christophe Boetsch, and Benjamin Ribba
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0301 basic medicine ,Oncology ,Cancer Research ,medicine.medical_specialty ,medicine.medical_treatment ,Population ,Models, Biological ,03 medical and health sciences ,Antineoplastic Agents, Immunological ,0302 clinical medicine ,Pharmacokinetics ,Cancer immunotherapy ,Neoplasms ,Internal medicine ,medicine ,Humans ,Immunologic Factors ,Dosing ,education ,education.field_of_study ,business.industry ,Cancer ,Receptors, Interleukin-2 ,Immunotherapy ,Models, Theoretical ,Prognosis ,medicine.disease ,Molecular Imaging ,Bioavailability ,Treatment Outcome ,030104 developmental biology ,030220 oncology & carcinogenesis ,Pharmacodynamics ,Cytokines ,Interleukin-2 ,business ,Biomarkers - Abstract
Purpose: Optimal dosing is critical for immunocytokine-based cancer immunotherapy to maximize efficacy and minimize toxicity. Cergutuzumab amunaleukin (CEA-IL2v) is a novel CEA-targeted immunocytokine. We set out to develop a mathematical model to predict intratumoral CEA-IL2v concentrations following various systemic dosing intensities. Experimental Design: Sequential measurements of CEA-IL2v plasma concentrations in 74 patients with solid tumors were applied in a series of differential equations to devise a model that also incorporates the peripheral concentrations of IL2 receptor–positive cell populations (i.e., CD8+, CD4+, NK, and B cells), which affect tumor bioavailability of CEA-IL2v. Imaging data from a subset of 14 patients were subsequently utilized to additionally predict antibody uptake in tumor tissues. Results: We created a pharmacokinetic/pharmacodynamic mathematical model that incorporates the expansion of IL2R-positive target cells at multiple dose levels and different schedules of CEA-IL2v. Model-based prediction of drug levels correlated with the concentration of IL2R-positive cells in the peripheral blood of patients. The pharmacokinetic model was further refined and extended by adding a model of antibody uptake, which is based on drug dose and the biological properties of the tumor. In silico predictions of our model correlated with imaging data and demonstrated that a dose-dense schedule comprising escalating doses and shortened intervals of drug administration can improve intratumoral drug uptake and overcome consumption of CEA-IL2v by the expanding population of IL2R-positive cells. Conclusions: The model presented here allows simulation of individualized treatment plans for optimal dosing and scheduling of immunocytokines for anticancer immunotherapy. Clin Cancer Res; 24(14); 3325–33. ©2018 AACR. See related commentary by Ruiz-Cerdá et al., p. 3236
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- 2018
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19. Polymer electrolyte fuel cell (PEMFC) based power system for long-term operation of leave-in-place sensors in Navy and Marine Corps applications
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D. Hooper, Maxwell Kerber, Alex Phipps, Lewis Hsu, J. Oiler, and A. Higier
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Battery (electricity) ,Renewable Energy, Sustainability and the Environment ,020209 energy ,Controller (computing) ,Energy Engineering and Power Technology ,Proton exchange membrane fuel cell ,02 engineering and technology ,Chemical reactor ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Automotive engineering ,Electric power system ,Fuel Technology ,Hydrogen fuel ,Boost converter ,0202 electrical engineering, electronic engineering, information engineering ,Environmental science ,Hydrogen fuel enhancement ,0210 nano-technology - Abstract
We present the details of an autonomous power-on-demand fuel cell system for operating remote sensor packages currently being developed by the US Navy. The system is designed to extend mission lifetime six-fold by replacing non-rechargeable primary batteries with stored hydrogen and a fuel cell. This system utilizes hydrogen gas generated through a reaction between the solid chemical sodium borohydride and water. The chemical delivery mechanism utilizes feedback from the fuel cell output voltage in order to determine the amount of sodium borohydride to be metered into the reaction vessel. The fuel cell can power the load directly or indirectly through a small rechargeable battery. A boost converter is used to increase the voltage output and an integrated power path controller sets whether load power is delivered via the fuel cell or battery. Two methods for chemical delivery are currently under investigation. The deployed system will increase battlefield persistence by greatly extending the lifetime of existing sensors while reducing risk of harm to the warfighter.
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- 2017
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20. The role of clinical pharmacology across novel treatment modalities
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Karen Thudium Mueller, Chi-Chung Li, and Alex Phipps
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Pharmacology ,medicine.medical_specialty ,Vaccines ,Clinical pharmacology ,Dose-Response Relationship, Drug ,business.industry ,MEDLINE ,Genetic Therapy ,Risk Assessment ,law.invention ,Text mining ,law ,Treatment modality ,Pharmacology, Clinical ,Medicine ,Humans ,Pharmacology (medical) ,Drug Interactions ,Interdisciplinary Communication ,Immunotherapy ,business ,Intensive care medicine - Published
- 2019
21. Modeling Longitudinal Preclinical Tumor Size Data to Identify Transient Dynamics in Tumor Response to Antiangiogenic Drugs
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Eamonn A. Gaffney, Mueller Hj, Jonathan Wagg, Philip K. Maini, Helen M. Byrne, Christophe Boetsch, Benjamin Ribba, Alex Phipps, and L.G. Hutchinson
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0301 basic medicine ,Oncology ,medicine.medical_specialty ,Chemotherapy ,Bevacizumab ,business.industry ,medicine.medical_treatment ,medicine.disease ,3. Good health ,Radiation therapy ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Breast cancer ,Vanucizumab ,030220 oncology & carcinogenesis ,Modeling and Simulation ,Internal medicine ,Monoclonal ,medicine ,Combined Modality Therapy ,Pharmacology (medical) ,Transient (computer programming) ,business ,medicine.drug - Abstract
Experimental evidence suggests that antiangiogenic therapy gives rise to a transient window of vessel normalization, within which the efficacy of radiotherapy and chemotherapy may be enhanced. Preclinical experiments that measure components of vessel normalization are invasive and expensive. We have developed a mathematical model of vascular tumor growth from preclinical time-course data in a breast cancer xenograft model. We used a mixed-effects approach for model parameterization, leveraging tumor size data to identify a period of enhanced tumor growth that could potentially correspond to the transient window of vessel normalization. We estimated the characteristics of the window for mice treated with an anti-VEGF antibody (bevacizumab) or with a bispecific anti-VEGF/anti-angiopoietin-2 antibody (vanucizumab). We show how the mathematical model could theoretically be used to predict how to coordinate antiangiogenic therapy with radiotherapy or chemotherapy to maximize therapeutic effect, reducing the need for preclinical experiments that directly measure vessel normalization parameters.
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- 2016
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22. Effect of the Wetting Agent Sodium Lauryl Sulfate on the Pharmacokinetics of Alectinib: Results From a Bioequivalence Study in Healthy Subjects
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Peter N. Morcos, Meret Martin-Facklam, Carolina Sturm, Ali Zeaiter, Neil Parrott, Elena Guerini, Alex Phipps, Katrijn Bogman, Georgina Dall, Ludger Banken, Marc Lindenberg, and Carsten Timpe
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Alectinib ,Chromatography ,integumentary system ,business.industry ,Sodium ,Cmax ,Pharmaceutical Science ,chemistry.chemical_element ,Bioequivalence ,Pharmacology ,030226 pharmacology & pharmacy ,Crossover study ,03 medical and health sciences ,0302 clinical medicine ,Pharmacokinetics ,chemistry ,030220 oncology & carcinogenesis ,Medicine ,Pharmacology (medical) ,Geometric mean ,business ,Active metabolite - Abstract
The anaplastic lymphoma kinase (ALK) inhibitor alectinib is an effective treatment for ALK-positive non-small-cell lung cancer. This bioequivalence study evaluated the in vivo performance of test 3 formulations with the reduced wetting agent sodium lauryl sulfate (SLS) content. This randomized, 4-period, 4-sequence, crossover study compared alectinib (600 mg) as 25%, 12.5%, and 3% SLS hard capsule formulations with the reference 50% SLS clinical formulation in healthy subjects under fasted conditions (n = 49), and following a high-fat meal (n = 48). Geometric mean ratios and 90% confidence intervals (CIs) for Cmax , AUC0-last , and AUC0-∞ of alectinib, its major active metabolite, M4, and alectinib plus M4 were determined for the test formulations versus the reference formulation. Bioequivalence was concluded if the 90%CIs were within the 80% to 125% boundaries. The 25% SLS formulation demonstrated bioequivalence to the reference 50% SLS formulation for Cmax , AUC0-last , and AUC0-∞ of alectinib, M4, and alectinib plus M4 under both fasted and fed conditions. Further reductions in SLS content (12.5% and 3% SLS) did not meet the bioequivalence criteria. Cross-group comparisons showed an approximately 3-fold positive food effect. Reducing SLS to 25% resulted in a formulation that is bioequivalent to the current 50% SLS formulation used in alectinib pivotal trials.
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- 2016
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23. Effect of Food and Esomeprazole on the Pharmacokinetics of Alectinib, a Highly Selective ALK Inhibitor, in Healthy Subjects
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Elena Guerini, Steven Blotner, Bogdana Balas, Meret Martin-Facklam, Carolina Sturm, Peter N. Morcos, Alex Phipps, Katrijn Bogman, Georgina Dall, and Neil Parrott
- Subjects
Alectinib ,Crizotinib ,business.industry ,medicine.drug_class ,Cmax ,Pharmaceutical Science ,Pharmacology ,030226 pharmacology & pharmacy ,Crossover study ,Esomeprazole ,ALK inhibitor ,03 medical and health sciences ,0302 clinical medicine ,Pharmacokinetics ,030220 oncology & carcinogenesis ,medicine ,Pharmacology (medical) ,business ,Active metabolite ,medicine.drug - Abstract
Alectinib, an anaplastic lymphoma kinase (ALK) inhibitor, is approved for treatment of patients with ALK+ non-small cell lung cancer who have progressed, on or are intolerant to, crizotinib. This study assessed the effect of a high-fat meal and the proton pump inhibitor, esomeprazole, on the pharmacokinetics (PK) of alectinib. This was an open-label, 2-group study in healthy subjects. In group 1 (n = 18), subjects were randomly assigned to a 2-treatment (A, fasted conditions; B, following a high-fat meal), 2-sequence (AB or BA) crossover assessment, separated by a 10-day washout. In group 2 (n = 24), subjects were enrolled in a 2-period, fixed-sequence crossover assessment to evaluate the effect of esomeprazole. PK parameters were evaluated for alectinib, its major similarly active metabolite, M4, and the combined exposure of alectinib and M4. Administration of alectinib following a high-fat meal substantially increased the combined exposure of alectinib and M4 to 331% (90%CI, 279%-393%) and 311% (90%CI, 273%-355%) for Cmax and AUC0-∞ , respectively, versus fasted conditions. Coadministration of esomeprazole had no clinically relevant effect on the combined exposure of alectinib and M4. Alectinib should be administered under fed conditions to maximize its bioavailability, whereas no restrictions are required with antisecretory agents.
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- 2016
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24. Evaluation of Acid Accelerators for an Off-Grid PEM Fuel Cell Power Station Utilizing Solid Sodium Borohydride for Hydrogen Storage
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Maxwell Kerber, Alex Phipps, Arthur Rubio, Lewis Hsu, Mindy Huang, Greg Anderson, and Michael D. Putnam
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Sodium borohydride ,chemistry.chemical_compound ,Hydrogen storage ,chemistry ,Power station ,business.industry ,Nuclear engineering ,Electrical engineering ,Proton exchange membrane fuel cell ,Grid ,business - Abstract
In rural areas, networkable environmental monitoring equipment is often used to provide continuous, real-time information without the need for a dedicated operator for maintenance or monitoring. However, power and energy availability are often controlling factors for operational lifetime when these systems are put on location. In these situations, batteries are often used as the main energy storage medium and require servicing or replacement when exhausted. This can lead high costs related to man-power and logistics to return and maintain the equipment at those locations. Sodium borohydride hydrolysis was once looked at as a promising way to store hydrogen for use in PEM fuel cells. Concerns regarding hydrogen storage capacity and recyclability of reaction products have prevented its use in larger transportation or energy storage applications. However, the energy density of sodium borohydride still makes the reaction suitable for specific applications where reuse is not needed. As such, present here a system utilizing solid sodium borohydride as a storage medium to meet on demand power needs of these types of systems. The system utilizes a PEM fuel cell integrated with an electro-mechanical system to control chemical metering and power management. We have previously shown results from our initial testing with solid sodium borohydride using commercial-off-the-shelf tablets for generating hydrogen when added to a reaction vessel containing water. Conceptually, a tablet would be introduced to the reaction vessel whenever additional hydrogen gas would be required. Operating in this manner would require good stability and reproducibility over multiple tablet reaction events. Initial testing showed good reaction rates when a cobalt catalyst was employed, either pre-doped into the solid tablet mixture or when the catalyst was pre-mixed with the water in the reaction vessel. Analysis of the gas mixture showed high quality hydrogen gas flows could be produced and sent to the PEM fuel cell for power production. However, concerns with the stability, safety, and handling of the catalyst have led to a need to identify a more green chemistry approach. We present here an alternative approach using common mineral and organic acids as hydrolysis accelerators that could be considered a greener approach to hydrogen generation for remote power applications. These include hydrochloric acid, phosphoric acid, citric acid, and acetic acid. Initial testing shows good reproducibility over multiple hydrogen generation events and reasonable reaction control. A comparison of hydrogen yield and gas composition is also shown. Finally, cost comparison between these accelerators is performed in order to assess their suitability in practical application.
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- 2016
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25. Clinical Micro-Dose Studies to Explore the Human Pharmacokinetics of Four Selective Inhibitors of Human Nav1.7 Voltage-Dependent Sodium Channels
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Hannah J. Pearce, Ian Gurrell, Neil J. Flanagan, Alex Phipps, Hannah M. Jones, Jill Segelbacher, Bill Speed, Daniela Fraier, Tanya Hay, Rob Webster, Paweł Dżygiel, Richard P. Butt, Laura Iavarone, Kevin Beaumont, and Jacquelynn Luckwell
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Adult ,Male ,0301 basic medicine ,Physiologically based pharmacokinetic modelling ,Adolescent ,Metabolic Clearance Rate ,Biological Availability ,Pharmacology ,Bioinformatics ,Models, Biological ,030226 pharmacology & pharmacy ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Double-Blind Method ,MicroDose ,Pharmacokinetics ,medicine ,Humans ,Pharmacology (medical) ,IC50 ,Voltage-Gated Sodium Channel Blockers ,Volume of distribution ,Sulfonamides ,Dose-Response Relationship, Drug ,business.industry ,Phenyl Ethers ,Chronic pain ,Hydrogen-Ion Concentration ,Middle Aged ,medicine.disease ,Bioavailability ,Dose–response relationship ,030104 developmental biology ,Area Under Curve ,business - Abstract
The emergence of genetic data linking Nav1.7 sodium channel over- and under- expression to human pain signalling has led to an interest in the treatment of chronic pain through inhibition of Nav1.7 channels. We describe the pharmacokinetic (PK) results of a clinical microdose study performed with four potent and selective Nav1.7 inhibitors and the subsequent modelling resulting in the selection of a single compound to explore Nav1.7 pharmacology at higher doses. A clinical microdose study to investigate the intravenous and oral PK of four compounds (PF-05089771, PF-05150122, PF-05186462 and PF-05241328) was performed in healthy volunteers. PK parameters were derived via noncompartmental analysis. A physiologically-based PK (PBPK) model was used to predict exposure and multiples of Nav1.7 50 % inhibitory concentration (IC50) for each compound at higher doses. Plasma clearance, volume of distribution and bioavailability ranged from 45 to 392 mL/min/kg, 13 to 36 L/kg and 38 to 110 %, respectively. The PBPK model for PF-05089771 predicted a 1 g oral dose would be required to achieve exposures of approximately 12× Nav1.7 IC50 at maximum concentration (C max), and approximately 3× IC50 after 12 h (minimum concentration [C min] for a twice-daily regimen). Lower multiples of Nav1.7 IC50 were predicted with the same oral doses of PF-05150122, PF-05186462, and PF-05241328. In a subsequent single ascending oral dose clinical study, the predictions for PF-05089771 compared well with observed data. Based on the human PK data obtained from the microdose study and subsequent modelling, PF-05089771 provided the best opportunity to explore Nav1.7 blockade for the treatment of acute or chronic pain conditions.
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- 2016
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26. Therapeutically-induced stable disease in oncology early clinical trials
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Francois Mercier, Paul Grimsey, Francesca Michielin, Georgina Meneses-Lorente, and Alex Phipps
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Male ,0301 basic medicine ,Oncology ,Cancer Treatment ,Progressive Diseases ,Disease ,Pathology and Laboratory Medicine ,Diagnostic Radiology ,0302 clinical medicine ,Stable Disease ,Neoplasms ,Medicine and Health Sciences ,Medicine ,Doubling time ,Clinical Trials (Cancer Treatment) ,Young adult ,Tomography ,Aged, 80 and over ,Clinical Trials as Topic ,Multidisciplinary ,medicine.diagnostic_test ,Radiology and Imaging ,Middle Aged ,Magnetic Resonance Imaging ,Tumor Burden ,030220 oncology & carcinogenesis ,Female ,Research Article ,Adult ,medicine.medical_specialty ,Drug Research and Development ,Adolescent ,Imaging Techniques ,Science ,Neuroimaging ,Research and Analysis Methods ,Models, Biological ,Young Adult ,03 medical and health sciences ,Signs and Symptoms ,Diagnostic Medicine ,Internal medicine ,Humans ,Clinical Trials ,Aged ,Pharmacology ,Treatment Guidelines ,Health Care Policy ,business.industry ,Biology and Life Sciences ,Cancer ,Magnetic resonance imaging ,Guideline ,medicine.disease ,Computed Axial Tomography ,Health Care ,Clinical trial ,030104 developmental biology ,Lesions ,Clinical Medicine ,business ,Neuroscience - Abstract
Rationale The RECIST guideline defines four categories of response to treatment for cancer patients according to post-baseline changes in tumor burden, hence ignoring disease history. However, if left untreated, tumors grow exponentially, implying that pretreatment changes in tumor size are key to thoroughly assess efficacy. We present a model-based approach to estimate the rates of changes in tumor mass, before and after treatment onset. Methods Sixty-eight patients were eligible for the analysis of tumor size data from a Phase 1 study evaluating the effect of emactuzumab. In addition to tumor size measured at baseline and every six weeks during treatment, a pre-baseline measurement was gathered for each patient. A longitudinal regression model was used to estimate the rates of tumor size change before and after treatment onset. Results The median pre-treatment tumor growth exponential rate was equal to 0.022 month-1, corresponding to a tumor size doubling time of 4 months, and the on-treatment median tumor shrinkage exponential rate was equal to 0.001 month-1. Among sixteen patients categorized as stable disease per RECIST, only five had similar slopes before and after treatment while nine actually improved. One patient in particular had a therapeutically induced stabilization of the disease. Conclusion Our analysis emphasizes the importance of collecting pre-baseline scans to distinguish therapeutically induced stable disease from cases where the tumor growth is not perturbed by treatment.
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- 2020
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27. Model-Based Assessments of CYP-Mediated Drug-Drug Interaction Risk of Alectinib: Physiologically Based Pharmacokinetic Modeling Supported Clinical Development
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Michael Gertz, Peter N. Morcos, Li Yu, Kuresh Youdim, Alex Phipps, Yumi Cleary, Neil Parrott, and Stephen Fowler
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Alectinib ,Physiologically based pharmacokinetic modelling ,Breakthrough therapy ,Carbazoles ,Pharmacology ,030226 pharmacology & pharmacy ,Models, Biological ,Risk Assessment ,Substrate Specificity ,Activation, Metabolic ,Cytochrome P-450 CYP2C8 ,03 medical and health sciences ,0302 clinical medicine ,Pharmacokinetics ,Drug Development ,Piperidines ,Anaplastic lymphoma kinase ,Medicine ,Cytochrome P-450 CYP3A ,Humans ,heterocyclic compounds ,Pharmacology (medical) ,Computer Simulation ,Drug Interactions ,Drug Approval ,Protein Kinase Inhibitors ,Active metabolite ,CYP3A4 ,business.industry ,United States Food and Drug Administration ,virus diseases ,United States ,Clinical trial ,Cytochrome P-450 CYP2C8 Inhibitors ,030220 oncology & carcinogenesis ,Cytochrome P-450 CYP3A Inhibitors ,Patient Safety ,business - Abstract
Alectinib is a selective anaplastic lymphoma kinase (ALK) inhibitor approved for the treatment of ALK-positive non-small cell lung cancer. Alectinib and its major active metabolite M4 exhibited drug-drug interaction (DDI) potential through cytochrome P450 (CYP) enzymes CYP3A4 and CYP2C8 in vitro. Clinical relevance of the DDI risk was investigated as part of a rapid development program to fulfill the breakthrough therapy designation. Therefore, a strategy with a combination of physiologically based pharmacokinetic (PBPK) modeling and limited clinical trials focused on generating informative data for modeling was made to ensure extrapolation ability of DDI risk. The PBPK modeling has provided mechanistic insight into the low victim DDI risk of alectinib through CYP3A4 by a novel two-dimensional analysis for fmCYP3A4 and FG , and demonstrated negligible CYPs 2C8 and 3A4 enzyme-modulating effects at clinically relevant exposure. This work supports that alectinib can be prescribed without dose adjustment for CYP-mediated DDI liabilities.
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- 2017
28. Standards and methods of power control for variable power bidirectional wireless power transfer
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Alex Phipps and Graham Sanborn
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Engineering ,Switched-mode power supply ,010505 oceanography ,business.industry ,020209 energy ,Automatic frequency control ,Transmitter ,Electrical engineering ,02 engineering and technology ,01 natural sciences ,Power budget ,Power (physics) ,0202 electrical engineering, electronic engineering, information engineering ,Electronic engineering ,Wireless ,Wireless power transfer ,business ,0105 earth and related environmental sciences ,Power control - Abstract
Unmanned and autonomous systems are used extensively for Navy missions. While most of these systems are able to operate without human interaction, limitations in power capacity place a fundamental limit on overall system autonomy. Inductive wireless power transfer provides an effective way to enhance unmanned systems (vehicles, sensors, etc.). This report examines different methods for efficiently controlling power modulation and determining which side, transmitter or receiver, commands power needs. The need for charging a wide array of systems and bidirectional power capabilities are considered, which point toward a need of underwater wireless power standards, a framework of which is proposed.
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- 2017
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29. Design considerations for an active rectifier circuit for bidirectional wireless power transfer
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Alex Phipps, Bruce Offord, and Maxwell Kerber
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Engineering ,business.industry ,020208 electrical & electronic engineering ,Transistor ,Electrical engineering ,02 engineering and technology ,Power factor ,law.invention ,Footprint (electronics) ,Rectifier ,law ,0202 electrical engineering, electronic engineering, information engineering ,Electronic engineering ,Maximum power transfer theorem ,Power semiconductor device ,Wireless power transfer ,business ,Active rectification - Abstract
The capability of bi-directional, underwater power transfer (both sending and receiving power) increases the functionality of underwater vehicles by allowing them to be charged and provide charge wirelessly to other systems without leaving the water. To minimize the footprint of the charging circuitry, a single transistor-based full-bridge circuit can be used to either send or receive power. This work focuses on the operation of the circuit in power receive mode, as an active rectifier. An algorithm common for active rectification is presented, and the effects of non-idealities on the timing control and efficiency is presented through experimental results.
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- 2017
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30. Abstract 690: Optimization of biopsy scheduling in clinical studies of T cell bispecifics through an integrated modeling and simulation, digital pathology and machine learning approach
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Oliver Grimm, Lucy Hutchinson, Richard Peck, Antoine Soubret, Alex Phipps, Jean-Eric Charoin, and Benjamin Ribba
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Cancer Research ,Schedule ,medicine.diagnostic_test ,Computer science ,business.industry ,Clinical study design ,medicine.medical_treatment ,Digital pathology ,Machine learning ,computer.software_genre ,Clinical trial ,Workflow ,Oncology ,Cancer immunotherapy ,Biopsy ,medicine ,Artificial intelligence ,Time point ,business ,computer - Abstract
In the context of cancer immunotherapy clinical trials, baseline and on-treatment tumor biopsies may provide important insight into whether a treatment is working as expected, and furthermore whether efficacy is anticipated. For tumor-retained antibodies that perturb the behaviour of immune cells, such as T cell bispecific antibodies (TCBs), spatial information derived from biopsy images may be particularly insightful. On-treatment biopsies in clinical trials are usually scheduled at a time point that is considered convenient for the study design and when therapeutic effects, such as T cell infiltration, are expected to be distinguishable in tumor tissue. To our knowledge, there have been no attempts to investigate optimal scheduling of on-treatment biopsy sample collection using quantitative approaches due to lack of clinical data at a sufficiently diverse range of time points. Our integrated tissue pathology, disease modeling and machine learning workflow is designed to select the time point at which on-treatment biopsies could be most informative for making reliable predictions of response to treatment. Leveraging around 20 baseline and on-treatment digitized biopsy images from patients undergoing treatment with immune stimulating TCBs, we train a mathematical model to simulate tumor cell/T cell interactions in the tumor microenvironment. The mathematical model produces an enriched dataset of “virtual” biopsy images corresponding to predictions at intermediate time points. The virtual biopsies are evaluated based on their ability to predict treatment response. Specific mechanisms of action of bispecific antibodies, such as upregulation of T cell activation and/or proliferation, are taken into account in the structure of the mathematical model. The model is tuned and validated using machine learning techniques, and a reserved “test” dataset comprising images that were not used to estimate model parameters is used to evaluate model performance. Our workflow has the potential to inform clinical study design by promoting a scientific basis for the selection of an on-treatment biopsy schedule. Future applications of this workflow include identification of tissue properties that may contribute to inter-individual variability, and simulations of novel doses and schedules for combinations of immune-modulating cancer therapies. Citation Format: Lucy G. Hutchinson, Antoine Soubret, Benjamin Ribba, Jean-Eric Charoin, Alex Phipps, Richard Peck, Oliver Grimm. Optimization of biopsy scheduling in clinical studies of T cell bispecifics through an integrated modeling and simulation, digital pathology and machine learning approach [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 690.
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- 2019
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31. Challenges and Opportunities for Quantitative Clinical Pharmacology in Cancer Immunotherapy: Something Old, Something New, Something Borrowed, and Something Blue
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Mark Stroh, Saroja Ramanujan, Zhi‐Xin Xhu, John D. Davis, Jean-Eric Charoin, Alex Phipps, Peter N. Morcos, Jian Xu, Jonathan Wagg, Jin Jin, David Carlile, Chi-Chung Li, and Benjamin Ribba
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Clinical pharmacology ,Psychotherapist ,Cancer immunotherapy ,law ,business.industry ,Modeling and Simulation ,medicine.medical_treatment ,Immunology ,medicine ,Pharmacology (medical) ,business ,law.invention - Abstract
Cancer immunotherapy (CIT) initiates or enhances the host immune response against cancer. Following decades of development, patients with previously few therapeutic options may now benefit from CIT. Although the quantitative clinical pharmacology (qCP) of previous classes of anticancer drugs has matured during this time, application to CIT may not be straightforward since CIT acts via the immune system. Here we discuss where qCP approaches might best borrow or start anew for CIT.
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- 2015
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32. Effect of Food and Esomeprazole on the Pharmacokinetics of Alectinib, a Highly Selective ALK Inhibitor, in Healthy Subjects
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Peter N, Morcos, Elena, Guerini, Neil, Parrott, Georgina, Dall, Steven, Blotner, Katrijn, Bogman, Carolina, Sturm, Bogdana, Balas, Meret, Martin-Facklam, and Alex, Phipps
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Adult ,Male ,Cross-Over Studies ,Carbazoles ,Esomeprazole ,Middle Aged ,Diet, High-Fat ,Healthy Volunteers ,Random Allocation ,Young Adult ,Piperidines ,Area Under Curve ,Humans ,Drug Interactions ,Female ,Protein Kinase Inhibitors - Abstract
Alectinib, an anaplastic lymphoma kinase (ALK) inhibitor, is approved for treatment of patients with ALK+ non-small cell lung cancer who have progressed, on or are intolerant to, crizotinib. This study assessed the effect of a high-fat meal and the proton pump inhibitor, esomeprazole, on the pharmacokinetics (PK) of alectinib. This was an open-label, 2-group study in healthy subjects. In group 1 (n = 18), subjects were randomly assigned to a 2-treatment (A, fasted conditions; B, following a high-fat meal), 2-sequence (AB or BA) crossover assessment, separated by a 10-day washout. In group 2 (n = 24), subjects were enrolled in a 2-period, fixed-sequence crossover assessment to evaluate the effect of esomeprazole. PK parameters were evaluated for alectinib, its major similarly active metabolite, M4, and the combined exposure of alectinib and M4. Administration of alectinib following a high-fat meal substantially increased the combined exposure of alectinib and M4 to 331% (90%CI, 279%-393%) and 311% (90%CI, 273%-355%) for C
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- 2016
33. Absorption, distribution, metabolism and excretion (ADME) of the ALK inhibitor alectinib: results from an absolute bioavailability and mass balance study in healthy subjects
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David J Moore, Li Yu, Peter N. Morcos, Mika Sato, Meret Martin-Facklam, Matt Whayman, Katja Heinig, Elena Guerini, Dieter Muri, Alex Phipps, Kosuke Kawashima, Katrijn Bogman, Keith Nieforth, and Hisakazu Chugai Seiyaku Kabushiki Kaisha Katsuki
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Alectinib ,Adult ,Male ,Health, Toxicology and Mutagenesis ,Carbazoles ,Biological Availability ,Pharmacology ,Toxicology ,030226 pharmacology & pharmacy ,Biochemistry ,Excretion ,03 medical and health sciences ,0302 clinical medicine ,MicroDose ,Pharmacokinetics ,Piperidines ,Humans ,Anaplastic Lymphoma Kinase ,Tissue Distribution ,Protein Kinase Inhibitors ,Active metabolite ,ADME ,Volume of distribution ,Cross-Over Studies ,Chemistry ,Receptor Protein-Tyrosine Kinases ,General Medicine ,Middle Aged ,Crossover study ,Healthy Volunteers ,030220 oncology & carcinogenesis - Abstract
1. Alectinib is a highly selective, central nervous system-active small molecule anaplastic lymphoma kinase inhibitor. 2. The absolute bioavailability, metabolism, excretion and pharmacokinetics of alectinib were studied in a two-period single-sequence crossover study. A 50 μg radiolabelled intravenous microdose of alectinib was co-administered with a single 600 mg oral dose of alectinib in the first period, and a single 600 mg/67 μCi oral dose of radiolabelled alectinib was administered in the second period to six healthy male subjects. 3. The absolute bioavailability of alectinib was moderate at 36.9%. Geometric mean clearance was 34.5 L/h, volume of distribution was 475 L and the hepatic extraction ratio was low (0.14). 4. Near-complete recovery of administered radioactivity was achieved within 168 h post-dose (98.2%) with excretion predominantly in faeces (97.8%) and negligible excretion in urine (0.456%). Alectinib and its major active metabolite, M4, were the main components in plasma, accounting for 76% of total plasma radioactivity. In faeces, 84% of dose was excreted as unchanged alectinib with metabolites M4, M1a/b and M6 contributing to 5.8%, 7.2% and 0.2% of dose, respectively. 5. This novel study design characterised the full absorption, distribution, metabolism and excretion properties in each subject, providing insight into alectinib absorption and disposition in humans.
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- 2016
34. Clinical Drug-Drug Interactions Through Cytochrome P450 3A (CYP3A) for the Selective ALK Inhibitor Alectinib
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Li Yu, Luigi De Petris, Meret Martin-Facklam, Yumi Cleary, Peter N. Morcos, Alex Phipps, Santiago Viteri, Walter Bordogna, Elena Guerini, Katrijn Bogman, and Georgina Dall
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Alectinib ,Adult ,Male ,Lung Neoplasms ,medicine.drug_class ,CYP3A ,Midazolam ,Carbazoles ,Pharmaceutical Science ,Pharmacology ,030226 pharmacology & pharmacy ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Pharmacokinetics ,Piperidines ,Carcinoma, Non-Small-Cell Lung ,Cytochrome P-450 CYP3A ,Medicine ,Anaplastic lymphoma kinase ,Humans ,Pharmacology (medical) ,Anaplastic Lymphoma Kinase ,Active metabolite ,Crizotinib ,Dose-Response Relationship, Drug ,business.industry ,Receptor Protein-Tyrosine Kinases ,Middle Aged ,Triazoles ,ALK inhibitor ,Treatment Outcome ,030220 oncology & carcinogenesis ,Female ,Rifampin ,business ,medicine.drug - Abstract
The efficacy and safety of alectinib, a central nervous system-active and selective anaplastic lymphoma kinase (ALK) inhibitor, has been demonstrated in patients with ALK-positive (ALK+) non-small cell lung cancer (NSCLC) progressing on crizotinib. Alectinib is mainly metabolized by cytochrome P450 3A (CYP3A) to a major similarly active metabolite, M4. Alectinib and M4 show evidence of weak time-dependent inhibition and small induction of CYP3A in vitro. We present results from 3 fixed-sequence studies evaluating drug-drug interactions for alectinib through CYP3A. Studies NP28990 and NP29042 enrolled 17 and 24 healthy subjects, respectively, and investigated potent CYP3A inhibition with posaconazole and potent CYP3A induction through rifampin, respectively, on the single oral dose pharmacokinetics (PK) of alectinib. A substudy of the global phase 2 NP28673 study enrolled 15 patients with ALK+ NSCLC to determine the effect of multiple doses of alectinib on the single oral dose PK of midazolam, a sensitive substrate of CYP3A. Potent CYP3A inhibition or induction resulted in only minor effects on the combined exposure of alectinib and M4. Multiple doses of alectinib did not influence midazolam exposure. These results suggest that dose adjustments may not be needed when alectinib is coadministered with CYP3A inhibitors or inducers or for coadministered CYP3A substrates.
- Published
- 2016
35. Effect of the Wetting Agent Sodium Lauryl Sulfate on the Pharmacokinetics of Alectinib: Results From a Bioequivalence Study in Healthy Subjects
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Peter N, Morcos, Neil, Parrott, Ludger, Banken, Carsten, Timpe, Marc, Lindenberg, Elena, Guerini, Georgina, Dall, Katrijn, Bogman, Carolina, Sturm, Ali, Zeaiter, Meret, Martin-Facklam, and Alex, Phipps
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Adult ,Male ,Cross-Over Studies ,Carbazoles ,Sodium Dodecyl Sulfate ,Capsules ,Fasting ,Middle Aged ,Diet, High-Fat ,Healthy Volunteers ,Surface-Active Agents ,Young Adult ,Piperidines ,Therapeutic Equivalency ,Humans ,Female - Abstract
The anaplastic lymphoma kinase (ALK) inhibitor alectinib is an effective treatment for ALK-positive non-small-cell lung cancer. This bioequivalence study evaluated the in vivo performance of test 3 formulations with the reduced wetting agent sodium lauryl sulfate (SLS) content. This randomized, 4-period, 4-sequence, crossover study compared alectinib (600 mg) as 25%, 12.5%, and 3% SLS hard capsule formulations with the reference 50% SLS clinical formulation in healthy subjects under fasted conditions (n = 49), and following a high-fat meal (n = 48). Geometric mean ratios and 90% confidence intervals (CIs) for C
- Published
- 2016
36. System Modeling of Piezoelectric Energy Harvesters
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Toshikazu Nishida and Alex Phipps
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Vibration ,Engineering ,Transducer ,Cantilever ,business.industry ,Acoustics ,PMUT ,Electrical and Electronic Engineering ,business ,Energy harvesting ,Piezoelectricity ,Beam (structure) ,Power (physics) - Abstract
For piezoelectric-based, vibration energy harvesting systems, a simplified resonant model is typically used to represent the piezoelectric transducer. Furthermore, the total amount of harvested power is calculated assuming an ideal and lossless power converter. A coupled, system-level model is developed that includes parasitic losses in the power converter for a system comprised of a cantilevered transducer beam and pulsed resonant converter. The accuracy of the system-level model is validated with experimental data, and it is shown that the simplified resonant model underpredicts the total harvested power by approximately 30% for the implemented system. In addition to capturing the electrical domain behavior of the system, the system-level model is also shown to accurately predict the effect of energy harvesting on the beam mechanics.
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- 2012
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37. Pregabalin Assay in a Patient with Widespread Neuropathic Pain and Late Onset Gluten Intolerance: Table 1
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Alex Phipps, Jon H. Raphael, and Dalvina Hanu-Cernat
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medicine.medical_specialty ,Malabsorption ,business.industry ,Pregabalin ,Gluten intolerance ,General Medicine ,Disease ,Phlebotomy ,medicine.disease ,Anesthesiology and Pain Medicine ,Pharmacokinetics ,Anesthesia ,Internal medicine ,Neuropathic pain ,medicine ,Neurology (clinical) ,business ,Blood sampling ,medicine.drug - Abstract
Objective. The aim of this study was to determine the pharmacokinetics of pregabalin in a patient with malabsorption secondary to celiac disease and compare the findings with the data available from pre-existing studies in healthy volunteer controls. Methods. A 39-year-old man consented to a 24-hour pregabalin assay with sequential pre and post-dose blood sampling. Results. The blood levels measured in this subject were no different to healthy male volunteers enrolled in previous studies. Conclusion. Although the results obtained are encouraging, the wide spectrum of effects and interactions of various drugs in malabsorption would suggest that therapy of any kind should be considered at individual level and monitored with blood assays. Wiley Periodicals, Inc.
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- 2011
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38. Evaluation of ventricular arrhythmias in early clinical pharmacology trials and potential consequences for later development
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Robert Kleiman, Jay W. Mason, Peter R. Kowey, J. Rick Turner, Kathleen Uhl, Mitchell W. Krucoff, Sherene S. Min, Christopher Newton-Cheh, John Finkle, Robert Pordy, Ivo Hynie, Alex Phipps, Adel Nada, Tara L. Dimino, Shari L. Targum, and Colette Strnadova
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medicine.medical_specialty ,Cost-Benefit Analysis ,Risk Assessment ,law.invention ,Toxicology ,Electrocardiography ,law ,Drug Discovery ,Prevalence ,medicine ,Humans ,Telemetry ,cardiovascular diseases ,Intensive care medicine ,Monitoring, Physiologic ,Electrocardiographic monitoring ,Clinical pharmacology ,Clinical Trials, Phase I as Topic ,business.industry ,Patient Selection ,Arrhythmias, Cardiac ,Clinical trial ,Drug development ,cardiovascular system ,Cardiology and Cardiovascular Medicine ,Early phase ,Risk assessment ,business - Abstract
This white paper, prepared by members of the Cardiac Safety Research Consortium, discusses several important issues regarding the evaluation of ventricular arrhythmias in early clinical pharmacology trials and their potential consequences for later clinical drug development. Ventricular arrhythmias are infrequent but potentially important medical events whose occurrence in early clinical pharmacology trials can dramatically increase safety concerns. Given the increasing concern with all potential safety signals and the resultant more extensive electrocardiographic monitoring of subjects participating in early phase trials, an important question must be addressed: Are relatively more frequent observations of ventricular arrhythmias related simply to more extensive monitoring, or are they genuinely related to the drug under development? The discussions in this paper provide current thinking and suggestions for addressing this question.
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- 2010
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39. Comparison of Different Algorithms for Predicting Clinical Drug-Drug Interactions, Based on the Use of CYP3A4 in Vitro Data: Predictions of Compounds as Precipitants of Interaction
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Alex Phipps, Jack Cook, Amanda Darekar, Kuresh Youdim, Susan Hurst, Feng Guo, David R. Plowchalk, R. Scott Obach, Odette A. Fahmi, Maurice Dickins, and Ruth Hyland
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Drug ,Midazolam ,media_common.quotation_subject ,Population ,Pharmaceutical Science ,Pharmacology ,Models, Biological ,Risk Assessment ,Substrate Specificity ,Structure-Activity Relationship ,Pharmacokinetics ,In vivo ,Cytochrome P-450 CYP3A ,Humans ,Computer Simulation ,Drug Interactions ,Enzyme Inhibitors ,education ,media_common ,education.field_of_study ,Molecular Structure ,biology ,CYP3A4 ,Chemistry ,Reproducibility of Results ,Cytochrome P450 ,Drug interaction ,Intestines ,Liver ,Enzyme Induction ,biology.protein ,Cytochrome P-450 CYP3A Inhibitors ,Algorithms ,Drug metabolism - Abstract
Cytochrome P450 3A4 (CYP3A4) is the most important enzyme in drug metabolism and because it is the most frequent target for pharmacokinetic drug-drug interactions (DDIs) it is highly desirable to be able to predict CYP3A4-based DDIs from in vitro data. In this study, the prediction of clinical DDIs for 30 drugs on the pharmacokinetics of midazolam, a probe substrate for CYP3A4, was done using in vitro inhibition, inactivation, and induction data. Two DDI prediction approaches were used, which account for effects at both the liver and intestine. The first was a model that simultaneously combines reversible inhibition, time-dependent inactivation, and induction data with static estimates of relevant in vivo concentrations of the precipitant drug to provide point estimates of the average magnitude of change in midazolam exposure. This model yielded a success rate of 88% in discerning DDIs with a mean -fold error of 1.74. The second model was a computational physiologically based pharmacokinetic model that uses dynamic estimates of in vivo concentrations of the precipitant drug and accounts for interindividual variability among the population (Simcyp). This model yielded success rates of 88 and 90% (for "steady-state" and "time-based" approaches, respectively) and mean -fold errors of 1.59 and 1.47. From these findings it can be concluded that in vivo DDIs for CYP3A4 can be predicted from in vitro data, even when more than one biochemical phenomenon occurs simultaneously.
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- 2009
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40. Demonstration of a wireless, self-powered, electroacoustic liner system
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Alex Phipps, Toshikazu Nishida, Mark Sheplak, Fei Liu, and Louis N. Cattafesta
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Ceramics ,Materials science ,Aircraft ,Acoustics and Ultrasonics ,Acoustics ,Flyback transformer ,Equipment Design ,Models, Theoretical ,Vibration ,law.invention ,Power (physics) ,Noise ,Electricity ,Energy Transfer ,Arts and Humanities (miscellaneous) ,Noise, Transportation ,law ,Pressure ,Sound pressure ,Acoustic impedance ,Energy harvesting ,Electrical impedance ,Helmholtz resonator - Abstract
This paper demonstrates the system operation of a self-powered active liner for the suppression of aircraft engine noise. The fundamental element of the active liner system is an electromechanical Helmholtz resonator (EMHR), which consists of a Helmholtz resonator with one of its rigid walls replaced with a circular piezoceramic composite plate. For this system demonstration, two EMHR elements are used, one for acoustic impedance tuning and one for energy harvesting. The EMHR used for acoustic impedance tuning is shunted with a variable resistive load, while the EMHR used for energy harvesting is shunted to a flyback power converter and storage element. The desired acoustic impedance conditions are determined externally, and wirelessly transmitted to the liner system. The power for the receiver and the impedance tuning circuitry in the liner are supplied by the harvested energy. Tuning of the active liner is demonstrated at three different sound pressure levels (148, 151, and 153 dB) in order to show the robustness of the energy harvesting and storage system. An acoustic tuning range of approximately 200 Hz is demonstrated for each of the three available power levels.
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- 2009
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41. A hydrogen leakage detection system using self-powered wireless hydrogen sensor nodes
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Anurag Kasyap, D. Johnson, B. Chou, Li-Chia Tien, X. Shengwen, J. Jun, Fan Ren, Toshikazu Nishida, Hung-Ta Wang, Lars F. Voss, Jenshan Lin, B. S. Kang, David P. Norton, Khai D. T. Ngo, Steve Pearton, P.W. Sadik, and Alex Phipps
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Engineering ,Hydrogen ,business.industry ,Amplifier ,Transmitter ,Electrical engineering ,chemistry.chemical_element ,Condensed Matter Physics ,Hydrogen sensor ,Electronic, Optical and Magnetic Materials ,chemistry ,Sensor node ,Low-power electronics ,Materials Chemistry ,Electronic engineering ,Wireless ,Electrical and Electronic Engineering ,business ,Energy harvesting - Abstract
A self-powered wireless hydrogen sensor node has been designed and developed from a system level approach. By using multi-source energy harvesting circuitry such as scavenged or “reclaimed” energy from light emitting and vibrational sources as the source of power for commercial low power microcontrollers, amplifiers, and RF transmitters, the sensor node is capable of conditioning and deciphering the output of hydrogen sensitive ZnO nanorods sensors. Upon the detection of a discernible amount of hydrogen, the system will ‘wake’ from an idle state to create a wireless data communication link to relay the detection of hydrogen to a central monitoring station. Two modes of operation were designed for the use of hydrogen detection. The first mode would sense for the presence of hydrogen above a set threshold, and alert a central monitoring station of the detection of significant levels of hydrogen. In the second mode of operation, actual hydrogen concentrations starting as low as 10 ppm are relayed to the receiver to track the amount of hydrogen present.
- Published
- 2007
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- View/download PDF
42. Thermal and biofouling effects on underwater wireless power transfer
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J. Oiler, Alex Phipps, John D. Rockway, Viktor Bana, Greg Anderson, and Maxwell Kerber
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Resistive touchscreen ,Materials science ,Fouling ,business.industry ,Nuclear engineering ,Electrical engineering ,engineering.material ,law.invention ,Coating ,law ,Heat transfer ,engineering ,Wireless ,Maximum power transfer theorem ,Wireless power transfer ,Resistor ,business - Abstract
This paper presents a characterization of the thermal effects and marine fouling on an undersea wireless power transfer system. The coils used in wireless power transfer experience elevated temperatures due to the resistive losses in the wire. Several different coating strategies to both protect the coils against seawater and dissipate the generated heat are investigated. In addition, the rise in temperature can increase the likelihood of marine bio-fouling on the exposed surfaces of the coils. A study of bio-fouling on the wireless power transfer coils and whether there might be increased microbial growth as a result of the power transfer is also explored.
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- 2015
- Full Text
- View/download PDF
43. Underwater wireless power transfer for maritime applications
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Alex Phipps, Maxwell Kerber, Greg Anderson, Viktor Bana, and John D. Rockway
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Electric power system ,Engineering ,Switched-mode power supply ,business.industry ,Power electronics ,Power module ,Electrical engineering ,Maximum power transfer theorem ,Wireless power transfer ,Underwater ,business ,Power budget - Abstract
This paper presents the development and implementation of an inductive, underwater wireless power transfer system for use with unmanned underwater vehicles (UUVs). Specifically, the design and fabrication of power transfer coils and power electronics is provided for a system capable of providing 75W to a load. At small standoff distances (
- Published
- 2015
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- View/download PDF
44. Marine Fouling and Thermal Dissipation of Undersea Wireless Power Transfer
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Viktor Bana, Greg Anderson, Maxwell Kerber, Alex Phipps, and John D. Rockway
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Biofouling ,Engineering ,Fouling ,business.industry ,Thermal insulation ,Electromagnetic coil ,Heat transfer ,Maximum power transfer theorem ,Electric power ,Wireless power transfer ,business ,Marine engineering - Abstract
This report describes the thermal effects and marine fouling on an undersea wireless power transfer system. The coils used in this wireless power transfer (WPT) experience elevated temperatures because of the resistive losses in the wire. Urethane and epoxy prevent water intrusion, but are thermal insulators and can lead to coil failure. Several different coating strategies to both protect the coils against seawater and dissipate the generated heat are investigated. In addition, the rise in temperature can increase the likelihood of marine biofouling on the exposed coil surfaces. A biofouling study on the wireless power transfer coils and whether there might be increased microbial growth as a result of the power transfer is also explored. The main benefit to the study provided here is to begin to gain an understanding of the effects thermal and marine fouling would have on WPT efficiency. The analysis will show that handling the heat should be a priority when implementing a high-power WPT system for unmanned underwater vehicles (UUVs). Coils must be carefully designed to dissipate the heat buildup but still maintain good transfer efficiency. Fortunately, the analysis will also show that the elevated temperatures on the coils is at a biocidal level, effectively killing off any marine microbes.
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- 2014
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45. Energy harvesting with coupled magnetostrictive resonators
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Alex Phipps, Antonio Palacios, Peyton Cavaroc, Antonio Matus-Vargas, Suketu Naik, Hugo G. Gonzalez-Hernandez, and Visarath In
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Vibration ,Resonator ,Coupling (physics) ,Materials science ,Cantilever ,Transducer ,Acoustics ,Magnetostriction ,Energy harvesting ,Galfenol - Abstract
We report the investigation of an energy harvesting system composed of coupled resonators with the magnetostrictive material Galfenol (FeGa). A coupled system of meso-scale (1-10 cm) cantilever beams for harvesting vibration energy is described for powering and aiding the performance of low-power wireless sensor nodes. Galfenol is chosen in this work for its durability, compared to the brittleness often encountered with piezoelectric materials, and high magnetomechanical coupling. A lumped model, which captures both the mechanical and electrical behavior of the individual transducers, is first developed. The values of the lumped element parameters are then derived empirically from fabricated beams in order to compare the model to experimental measurements. The governing equations of the coupled system lead to a system of differential equations with all-to-all coupling between transducers. An analysis of the system equations reveals different patterns of collective oscillations. Among the many different patterns, a synchronous state appears to yield the maximum energy that can be harvested by the system. Experiments on coupled system shows that the coupled system exhibits synchronization and an increment in the output power. Discussion of the required power converters is also included.
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- 2014
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46. Population pharmacokinetics (popPK) and exposure-response (ER) analyses to confirm alectinib 600 mg BID dose selection in a crizotinib-progressed or intolerant population
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Ronan Carnac, Elena Guerini, Bogdana Balas, Joy C. Hsu, Ali Zeaiter, Volkmar Henschel, Meret Martin-Facklam, Peter N. Morcos, Alex Phipps, Katrijn Bogman, and Nicolas Frey
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Alectinib ,Cancer Research ,education.field_of_study ,Crizotinib ,business.industry ,medicine.drug_class ,Population ,Population pharmacokinetics ,Pharmacology ,030226 pharmacology & pharmacy ,respiratory tract diseases ,ALK inhibitor ,03 medical and health sciences ,0302 clinical medicine ,Oncology ,hemic and lymphatic diseases ,030220 oncology & carcinogenesis ,Medicine ,Accelerated approval ,business ,education ,Exposure response ,medicine.drug ,Dose selection - Abstract
e20598Background: Alectinib, a potent and selective CNS-active ALK inhibitor, which has received FDA accelerated approval for treatment of patients with ALK+ NSCLC who have progressed on, or are in...
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- 2016
- Full Text
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47. Modeling tumor size time course in platinum resistant/refractory ovarian cancer patients treated with vanucizumab
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Vincent Buchheit, Angelika Lahr, Francois Mercier, Christophe Boetsch, Benjamin Ribba, Alex Phipps, Kevin Smart, and Oliver Krieter
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Tumor angiogenesis ,Cancer Research ,Tumor size ,biology ,business.industry ,medicine.disease ,Oncology ,Refractory ,Vanucizumab ,Time course ,medicine ,Cancer research ,biology.protein ,Antibody ,Ovarian cancer ,business ,Platinum resistant - Abstract
e17042Background: Vanucizumab is a novel bi-specific IgG-like antibody which is directed against both VEGF-A and ANG2, two key factors in tumor angiogenesis. As such, vanucizumab represents an enco...
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- 2016
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48. Case studies addressing human pharmacokinetic uncertainty using a combination of pharmacokinetic simulation and alternative first in human paradigms
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Mark Savage, Alex Phipps, Tanya Hay, Marie Simpson, Rachelle Christian, Anthony Harrison, Louise Taylor, Kevin Beaumont, Ian Gurrell, Sarah Kempshall, Jonathan Duckworth, Mark Seymour, Maurice Dickins, Gill Allan, Lynn Purkins, Paul Turnpenny, and Iain Gardner
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Adult ,Male ,Physiologically based pharmacokinetic modelling ,Pyrrolidines ,Health, Toxicology and Mutagenesis ,Statistics as Topic ,Drug Evaluation, Preclinical ,Computational biology ,Population based ,Pharmacology ,Toxicology ,Animal Testing Alternatives ,Biochemistry ,Models, Biological ,Young Adult ,Dogs ,Pharmacokinetics ,MicroDose ,In vivo ,Drug Discovery ,Retrospective analysis ,Medicine ,Animals ,Humans ,Anilides ,Naphthyridines ,Human studies ,business.industry ,General Medicine ,First in human ,Rats ,Microsomes, Liver ,business ,Selective Serotonin Reuptake Inhibitors - Abstract
PF-184298 ((S)-2,3-dichloro-N-isobutyl-N-pyrrolidin-3-ylbenzamide) and PF-4776548 ((3-(4-fluoro-2-methoxy-benzyl)-7-hydroxy-8,9-dihydro-3H,7H-pyrrolo[2,3-c][1,7]naphthyridin-6-one)) are novel compounds which were selected to progress to human studies. Discordant human pharmacokinetic predictions arose from pre-clinical in vivo studies in rat and dog, and from human in vitro studies, resulting in a clearance prediction range of 3 to >20 mL min⁻¹ kg⁻¹ for PF-184298, and 5 to >20 mL min⁻¹ kg⁻¹ for PF-4776548. A package of work to investigate the discordance for PF-184298 is described. Although ultimately complementary to the human pharmacokinetic data in characterising the disposition of PF-184298 in humans, these data did not provide any further confidence in pharmacokinetic prediction. A fit for purpose human pharmacokinetic study was conducted for each compound, with an oral pharmacologically active dose for PF-184298, and an intravenous and oral microdose for PF-4776548. This provided a relatively low cost, clear decision making approach, resulting in the termination of PF-4776548 and further progression of PF-184298. A retrospective analysis of the data showed that, if the tools had been available at the time, the pharmacokinetics of PF-184298 in human could have been predicted from a population based simulation tool in combination with physicochemical properties and in vitro human intrinsic clearance.
- Published
- 2011
49. Development of kinetic energy harvesting systems for vehicle applications
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Alicia Powers, Maxwell Kerber, Dung Phung, Alex Phipps, Richard L. Waters, and Brian Dick
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Acceleration ,Engineering ,Transducer ,business.industry ,Power electronics ,Electronic engineering ,Wireless ,Electronics ,business ,Energy harvesting ,Wireless sensor network ,Power (physics) - Abstract
This work demonstrates the implementation of a functional kinetic energy harvester designed to power wireless sensor electronics used in vehicular applications. The design, fabrication, and experimental characterization of a complete electrodynamic (magnetic) energy harvesting system capable of delivering in excess of 10 mW from 100 milli-g's of acceleration is presented. Unlike previous energy harvesting research, which typically focuses on individual components for proof-of-concept testing, the system implemented for this work includes the integration of a low-frequency transducer, power electronics circuitry, and a rechargeable storage element, all of which are required for a functional system. The design trade-offs, which result from the integration of these system components are examined and design rules for maximizing efficiency are given. Finally, field testing is presented, which demonstrates the ability of the system to operate over a range of different vehicle speeds.
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- 2011
50. Development of MEMS-based Piezoelectric Vibration Energy Harvesters
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Mark Sheplak, Toshikazu Nishida, Alex Phipps, Anurag Kasyap, and Lou Cattafesta
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Microelectromechanical systems ,Vibration ,Engineering ,Cantilever ,business.industry ,Electric potential energy ,Electronic engineering ,Mechanical engineering ,Dissipation ,Proof mass ,business ,Piezoelectricity ,Energy (signal processing) - Abstract
In this paper, the development of a first generation MEMS-based piezoelectric energy harvester capable of converting ambient vibrations into storable electrical energy is presented. The energy harvester is designed using a validated analytical electromechanical Lumped Element Model (LEM) that accurately predicts the behavior of a piezoelectric composite structure. The MEMS device is fabricated using standard sol gel PZT and conventional surface and bulk micro processing techniques. It consists of a piezoelectric composite cantilever beam (Si/SiO 2 /Ti/Pt/PZT/Pt/Au) with a proof mass at one end. A prototype device packaged in a 5 mm2 area produces 0.98 µW rms power into an optimal resistive load when excited with an acceleration of 1 m/s2 at its resonant frequency of 129 Hz. Although the model predicts the general behavior of the device accurately, knowledge of the overall system damping is critical to accurately predict the power output, and therefore individual dissipation mechanisms in the system must be investigated. This effort lays the foundation for future development of MEMS piezoelectric energy harvester arrays as a potential power solution for self sustaining wireless embedded systems. The electromechanical model further enables intelligent and optimal design of these energy harvesters for specific applications minimizing prototype test runs.
- Published
- 2011
- Full Text
- View/download PDF
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