Further Considerations Towards an Effective and Efficient Oncology Drug Discovery DMPK Strategy

2020 ◽  
Vol 21 (2) ◽  
pp. 145-162 ◽  
Author(s):  
Beth Williamson ◽  
Nicola Colclough ◽  
Adrian John Fretland ◽  
Barry Christopher Jones ◽  
Rhys Dafydd Owen Jones ◽  
...  

Background: DMPK data and knowledge are critical in maximising the probability of developing successful drugs via the application of in silico, in vitro and in vivo approaches in drug discovery. Methods: The evaluation, optimisation and prediction of human pharmacokinetics is now a mainstay within drug discovery. These elements are at the heart of the ‘right tissue’ component of AstraZeneca’s ‘5Rs framework’ which, since its adoption, has resulted in increased success of Phase III clinical trials. With the plethora of DMPK related assays and models available, there is a need to continually refine and improve the effectiveness and efficiency of approaches best to facilitate the progression of quality compounds for human clinical testing. Results: This article builds on previously published strategies from our laboratories, highlighting recent discoveries and successes, that brings our AstraZeneca Oncology DMPK strategy up to date. We review the core aspects of DMPK in Oncology drug discovery and highlight data recently generated in our laboratories that have influenced our screening cascade and experimental design. We present data and our experiences of employing cassette animal PK, as well as re-evaluating in vitro assay design for metabolic stability assessments and expanding our use of freshly excised animal and human tissue to best inform first time in human dosing and dose escalation studies. Conclusion: Application of our updated drug-drug interaction and central nervous system drug exposure strategies are exemplified, as is the impact of physiologically based pharmacokinetic and pharmacokinetic-pharmacodynamic modelling for human predictions.

Cells ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 1378
Author(s):  
Peyton Gibler ◽  
Jeffrey Gimble ◽  
Katie Hamel ◽  
Emma Rogers ◽  
Michael Henderson ◽  
...  

Human adipose-derived stromal/stem cells (hASC) are widely used for in vitro modeling of physiologically relevant human adipose tissue. These models are useful for the development of tissue constructs for soft tissue regeneration and 3-dimensional (3D) microphysiological systems (MPS) for drug discovery. In this systematic review, we report on the current state of hASC culture and assessment methods for adipose tissue engineering using 3D MPS. Our search efforts resulted in the identification of 184 independent records, of which 27 were determined to be most relevant to the goals of the present review. Our results demonstrate a lack of consensus on methods for hASC culture and assessment for the production of physiologically relevant in vitro models of human adipose tissue. Few studies have assessed the impact of different 3D culture conditions on hASC adipogenesis. Additionally, there has been a limited use of assays for characterizing the functionality of adipose tissue in vitro. Results from this study suggest the need for more standardized culture methods and further analysis on in vitro tissue functionality. These will be necessary to validate the utility of 3D MPS as an in vitro model to reduce, refine, and replace in vivo experiments in the drug discovery regulatory process.


2020 ◽  
Vol 10 (7) ◽  
pp. 2376 ◽  
Author(s):  
Rob C. van Wijk ◽  
Rami Ayoun Alsoud ◽  
Hans Lennernäs ◽  
Ulrika S. H. Simonsson

The increasing emergence of drug-resistant tuberculosis requires new effective and safe drug regimens. However, drug discovery and development are challenging, lengthy and costly. The framework of model-informed drug discovery and development (MID3) is proposed to be applied throughout the preclinical to clinical phases to provide an informative prediction of drug exposure and efficacy in humans in order to select novel anti-tuberculosis drug combinations. The MID3 includes pharmacokinetic-pharmacodynamic and quantitative systems pharmacology models, machine learning and artificial intelligence, which integrates all the available knowledge related to disease and the compounds. A translational in vitro-in vivo link throughout modeling and simulation is crucial to optimize the selection of regimens with the highest probability of receiving approval from regulatory authorities. In vitro-in vivo correlation (IVIVC) and physiologically-based pharmacokinetic modeling provide powerful tools to predict pharmacokinetic drug-drug interactions based on preclinical information. Mechanistic or semi-mechanistic pharmacokinetic-pharmacodynamic models have been successfully applied to predict the clinical exposure-response profile for anti-tuberculosis drugs using preclinical data. Potential pharmacodynamic drug-drug interactions can be predicted from in vitro data through IVIVC and pharmacokinetic-pharmacodynamic modeling accounting for translational factors. It is essential for academic and industrial drug developers to collaborate across disciplines to realize the huge potential of MID3.


Author(s):  
Patrick A. Murphy ◽  
Noor Jailkhani ◽  
Sarah-Anne Nicholas ◽  
Amanda M. Del Rosario ◽  
Jeremy L. Balsbaugh ◽  
...  

Objective: Exposure of the arterial endothelium to low and disturbed flow is a risk factor for the erosion and rupture of atherosclerotic plaques and aneurysms. Circulating and locally produced proteins are known to contribute to an altered composition of the extracellular matrix at the site of lesions, and to contribute to inflammatory processes within the lesions. We have previously shown that alternative splicing of FN (fibronectin) protects against flow-induced hemorrhage. However, the impact of alternative splicing of FN on extracellular matrix composition remains unknown. Approach and Results: Here, we perform quantitative proteomic analysis of the matrisome of murine carotid arteries in mice deficient in the production of FN splice isoforms containing alternative exons EIIIA and EIIIB (FN-EIIIAB null) after exposure to low and disturbed flow in vivo. We also examine serum-derived and endothelial-cell contributions to the matrisome in a simplified in vitro system. We found flow-induced differences in the carotid artery matrisome that were impaired in FN-EIIIAB null mice. One of the most interesting differences was reduced recruitment of FBLN1 (fibulin-1), abundant in blood and not locally produced in the intima. This defect was validated in our in vitro assay, where FBLN1 recruitment from serum was impaired by the absence of these alternatively spliced segments. Conclusions: Our results reveal the extent of the dynamic alterations in the matrisome in the acute response to low and disturbed flow and show how changes in the splicing of FN, a common response in vascular inflammation and remodeling, can affect matrix composition.


Perfusion ◽  
2019 ◽  
Vol 35 (3) ◽  
pp. 209-216 ◽  
Author(s):  
Samantha H Dallefeld ◽  
Jennifer Sherwin ◽  
Kanecia O Zimmerman ◽  
Kevin M Watt

Background: Dexmedetomidine is a sedative administered to minimize distress and decrease the risk of life threatening complications in children supported with extracorporeal membrane oxygenation. The extracorporeal membrane oxygenation circuit can extract drug and decrease drug exposure, placing the patient at risk of therapeutic failure. Objective: To determine the extraction of dexmedetomidine by the extracorporeal membrane oxygenation circuit. Materials and methods: Dexmedetomidine was studied in three closed-loop circuit configurations to isolate the impact of the oxygenator, hemofilter, and tubing on circuit extraction. Each circuit was primed with human blood according to standard practice for Duke Children’s Hospital, and flow was set to 1 L/min. Dexmedetomidine was dosed to achieve a therapeutic concentration of ~600 pg/mL. Dexmedetomidine was added to a separate tube of blood to serve as a control and evaluate for natural drug degradation. Serial blood samples were collected over 24 hours and concentrations were quantified with a validated assay. Drug recovery was calculated at each time point. Results: Dexmedetomidine was highly extracted by the oxygenator evidenced by a mean recovery of 62-67% at 4 hours and 23-34% at 24 hours in circuits with an oxygenator in-line. In contrast, mean recovery with the oxygenator removed was 96% at 4 hours and 93% at 24 hours. Dexmedetomidine was stable over time with a mean recovery in the control samples of 102% at 24 hours. Conclusion: These results suggest dexmedetomidine is extracted by the oxygenator in the extracorporeal membrane oxygenation circuit which may result in decreased drug exposure in vivo.


2019 ◽  
Vol 20 (2) ◽  
pp. 91-102 ◽  
Author(s):  
Li Di

Background:Carboxylesterases (CES) play a critical role in catalyzing hydrolysis of esters, amides, carbamates and thioesters, as well as bioconverting prodrugs and soft drugs. The unique tissue distribution of CES enzymes provides great opportunities to design prodrugs or soft drugs for tissue targeting. Marked species differences in CES tissue distribution and catalytic activity are particularly challenging in human translation.Methods:Review and summarization of CES fundamentals and applications in drug discovery and development.Results:Human CES1 is one of the most highly expressed drug metabolizing enzymes in the liver, while human intestine only expresses CES2. CES enzymes have moderate to high inter-individual variability and exhibit low to no expression in the fetus, but increase substantially during the first few months of life. The CES genes are highly polymorphic and some CES genetic variants show significant influence on metabolism and clinical outcome of certain drugs. Monkeys appear to be more predictive of human pharmacokinetics for CES substrates than other species. Low risk of clinical drug-drug interaction is anticipated for CES, although they should not be overlooked, particularly interaction with alcohols. CES enzymes are moderately inducible through a number of transcription factors and can be repressed by inflammatory cytokines.Conclusion:Although significant advances have been made in our understanding of CESs, in vitro - in vivo extrapolation of clearance is still in its infancy and further exploration is needed. In vitro and in vivo tools are continuously being developed to characterize CES substrates and inhibitors.


2020 ◽  
Vol 15 (2) ◽  
pp. 92-112 ◽  
Author(s):  
Katerina I. Slavova ◽  
Lozan T. Todorov ◽  
Nataliya P. Belskaya ◽  
Mauricio A. Palafox ◽  
Irena P. Kostova

Background: The impact of cancer on modern society cannot be emphasized enough in terms of both economic and human costs. Cancer treatments are known, unfortunately, for their side effects – frequently numerous and severe. Drug resistance is another issue medical professionals have to tackle when dealing with neoplastic illnesses. Cancer rates are rising worldwide due to various factors - low-quality nutrition, air and water pollution, tobacco use, etc. For those and many other reasons, drug discovery in the field of oncology is a top priority in modern medical science. Objective: To present the reader with the latest in cancer drug discovery with regard to 1,2,3-triazole- containing molecules in a clear, concise way so as to make the present review a useful tool for researchers. Methods: Available information present on the role of 1,2,3-triazoles in cancer treatment was collected. Data was collected from scientific literature, as well as from patents. Results: A vast number of triazole-containing molecules with antiproliferative properties have been proposed, synthesized and tested for anticancer activity both in vitro and in vivo. The substances vary greatly when considering molecular structure, proposed mechanisms of action and affected cancer cell types. Conclusion: Triazole-containing molecules with anticancer activity are being widely synthesized and extensively tested. They vary significantly in terms of both structure and mechanism of action. The methods for their preparation and administration are well established and with proven reproducibility. These facts suggest that triazoles may play an important role in the discovery of novel antiproliferative medications with improved effectiveness and safety profile.


Parasitology ◽  
2011 ◽  
Vol 139 (2) ◽  
pp. 208-220 ◽  
Author(s):  
CHRISTIAN KROPF ◽  
KARIM DEBACHE ◽  
CHRISTOPH RAMPA ◽  
FABIENNE BARNA ◽  
MICHELLE SCHORER ◽  
...  

SUMMARYThe impact of di-cationic pentamidine-analogues againstToxoplama gondii(Rh- and Me49-background) was investigated. The 72 h-growth assays showed that the arylimidamide DB750 inhibited the proliferation of tachyzoites ofT. gondii RhandT. gondii Me49with an IC50of 0·11 and 0·13μm, respectively. Pre-incubation of fibroblast monolayers with 1μmDB750 for 12 h and subsequent culture in the absence of the drug also resulted in a pronounced inhibiton of parasite proliferation. However, upon 5–6 days of drug exposure,T. gondiitachyzoites adapted to the compound and resumed proliferation up to a concentration of 1·2μm. Out of a set of 32 di-cationic compounds screened forin vitroactivity againstT. gondii,the arylimidamide DB745, exhibiting an IC50of 0·03μmand favourable selective toxicity was chosen for further studies. DB745 also inhibited the proliferation of DB750-adaptedT. gondii(IC50=0·07μm). In contrast to DB750, DB745 also had a profound negative impact on extracellular non-adaptedT. gondiitachyzoites, but not on DB750-adaptedT. gondii. Adaptation ofT. gondiito DB745 (up to a concentration of 0·46μm) was much more difficult to achieve and feasible only over a period of 110 days. In cultures infected with DB750-adaptedT. gondiiseemingly intact parasites could occasionally be detected by TEM. This illustrates the astonishing capacity ofT. gondiitachyzoites to adapt to environmental changes, at least underin vitroconditions, and suggests that DB745 could be an interesting drug candidate for further assessments in appropriatein vivomodels.


2014 ◽  
Vol 59 (1) ◽  
pp. 622-632 ◽  
Author(s):  
Arnold Louie ◽  
Michael T. Boyne ◽  
Vikram Patel ◽  
Clayton Huntley ◽  
Weiguo Liu ◽  
...  

ABSTRACTA recent report found that generic parenteral vancomycin products may not havein vivoefficacies equivalent to those of the innovator in a neutropenic murine thigh infection model despite having similarin vitromicrobiological activities and murine serum pharmacokinetics. We compared thein vitroandin vivoactivities of six of the parenteral vancomycin products available in the United States. Thein vitroassessments for the potencies of the vancomycin products included MIC/minimal bactericidal concentration (MBC) determinations, quantifying the impact of human and murine serum on the MIC values, and time-kill studies. Also, the potencies of the vancomycin products were quantified with a biological assay, and the human and mouse serum protein binding rates for the vancomycin products were measured. Thein vivostudies included dose-ranging experiments with the 6 vancomycin products for three isolates ofStaphylococcus aureusin a neutropenic mouse thigh infection model. The pharmacokinetics of the vancomycin products were assessed in infected mice by population pharmacokinetic modeling. No differences were seen across the vancomycin products with regard to anyin vitroevaluation. Inhibitory sigmoid maximal bacterial kill (Emax) modeling of the relationship between vancomycin dosage and the killing of the bacteria in micein vivoyielded similarEmaxand EC50(drug exposure driving one-halfEmax) values for bacterial killing. Further, there were no differences in the pharmacokinetic clearances of the 6 vancomycin products from infected mice. There were no important pharmacodynamic differences in thein vitroorin vivoactivities among the six vancomycin products evaluated.


2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S485-S485
Author(s):  
Sarah McGuffin ◽  
Steven Mullen ◽  
Julie Early ◽  
Tanya Parish

Abstract Background Nontuberculous mycobacteria (NTM), particularly Mycobacterium avium complex and Mycobacterium abscessus complex, cause significant morbidity and mortality in patients with impaired host immunity or pre-existing structural lung conditions. NTM infections are increasing at an alarming rate worldwide and there is a dearth of progress in regard to the development of efficacious and tolerable drugs to treat such infections. Traditional drug discovery screens do not account for the diverse physiological conditions, microenvironments, and compartments that the bacilli encounter during human infection. In order to help populate the NTM drug pipeline, and explore the disconnect between in vitro activity, in vivo activity, and clinical outcomes, we are developing a high throughput in vitro assay platform that will more closely model the unique infection-relevant conditions encountered by NTM. Methods We are developing and validating a suite of in vitro assays that screen compounds for activity against extracellular planktonic bacteria, extracellular bacteria within biofilms, intracellular bacteria, and nutrient-starved non-replicating bacteria. Results We are using both the smooth and rough morphotypes of M. abscessus and M. avium. We have validated high throughput assays to pharmaceutical standards for replicating and non-replicating M. abscessus. We have also tested a panel of 18 known anti-mycobacterial compounds. Assay development is currently underway to test compounds for activity against NTM in biofilm and inside macrophages as well. Conclusion To enhance hit identification for scaffolds to use as starting points for NTM drug development, focused libraries of compounds that have undergone significant preclinical profiling and/or compounds with known activity against M. tuberculosis (TB) will be screened. Such a “piggyback” approach usurps advances made in TB drug development and leverages them for NTM drug discovery. This will help expedite novel drug development, reduce attrition rate, and offer a shorter route to clinical use as it exploits the prior investment in medicinal chemistry, pharmacology, and toxicology. Disclosures All authors: No reported disclosures.


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