Various Stages Of Drug Development Research Articles

Applications of Quantitative Systems Pharmacology in Model‐Informed Drug Discovery: Perspective on Impact and Opportunities

Quantitative systems pharmacology (QSP) approaches have been increasingly applied in the pharmaceutical since the landmark white paper published in 2011 by a National Institutes of Health working group brought attention to the discipline. In this perspective, we discuss QSP in the context of other modeling approaches and highlight the impact of QSP across various stages of drug development and therapeutic areas. We discuss challenges to the field as well as future opportunities.

Quorum-sensing system in Acinetobacter baumannii: a potential target for new drug development.

Acinetobacter baumannii causes several nosocomial infections and poses major threat when it is multidrug resistant. Even pan drug-resistant strains have been reported in some countries. The intensive care unit (ICU) mortality rate ranged from 45.6% to 60.9% and it is as high as 84.3% when ventilator-associated pneumonia was caused by XDR (extensively drug resistant) A. baumannii. Acinetobacter baumannii constituted 9.4% of all Gram-negative organisms throughout the hospital and 22.6% in the ICUs according to a study carried out in an Indian hospital. One of the major factors contributing to drug resistance in A. baumannii infections is biofilm development. Quorum sensing (QS) facilitates biofilm formation and therefore the search for 'quorum quenchers' has increased recently. Such compounds are expected to inhibit biofilm formation and hence reduce/prevent development of drug resistance in the bacteria. Some of these compounds also target synthesis of some virulence factors (VF). Several candidate drugs have been identified and are at various stages of drug development. Since quorum quenching, inhibition of biofilm formation and inhibition of VF synthesis do not pose any threat to the DNA replication and cell division of the bacteria, chances of resistance development to such compounds is presumably rare. Thus, these compounds ideally qualify as adjunct therapeutics and could be administered along with an antibiotic to reduce chances of resistance development and also to increase the effectiveness of antimicrobial therapy. This review describes the state-of-art in QS process in Gram-negative bacteria in general and in A. baumannii in particular. This article elaborates the nature of QS mediators, their characteristics, and the methods for their detection and quantification. Various potential sites in the QS pathway have been highlighted as drug targets and the candidate quorum quenchers which inhibit the mediator's synthesis or function are enlisted.

Development of a Korean-specific virtual population for physiologically based pharmacokinetic modelling and simulation.

Physiologically based pharmacokinetic (PBPK) modelling and simulation is a useful tool in predicting the PK profiles of a drug, assessing the effects of covariates such as demographics, ethnicity, genetic polymorphisms and disease status on the PK, and evaluating the potential of drug-drug interactions. We developed a Korean-specific virtual population for the SimCYP® Simulator (version 15 used) and evaluated the population's predictive performance using six substrate drugs (midazolam, S-warfarin, metoprolol, omeprazole, lorazepam and rosuvastatin) of five major drug metabolizing enzymes (DMEs) and two transporters. Forty-three parameters including the proportion of phenotypes in DMEs and transporters were incorporated into the Korean-specific virtual population. The simulated concentration-time profiles in Koreans were overlapped with most of the observed concentrations for the selected substrate drugs with a<2-fold difference in clearance. Furthermore, we found some drug models within the SimCYP® library can be improved, e.g., the minor allele frequency of ABCG2 and the fraction metabolized by UGT2B15 should be incorporated for rosuvastatin and lorazepam, respectively. The Korean-specific population can be used to evaluate the impact of ethnicity on the PKs of a drug, particularly in various stages of drug development.

Enzymatic Transition States and Drug Design.

Transition state theory teaches that chemically stable mimics of enzymatic transition states will bind tightly to their cognate enzymes. Kinetic isotope effects combined with computational quantum chemistry provides enzymatic transition state information with sufficient fidelity to design transition state analogues. Examples are selected from various stages of drug development to demonstrate the application of transition state theory, inhibitor design, physicochemical characterization of transition state analogues, and their progress in drug development.

New Drugs and Vaccines for Tuberculosis

Tuberculosis (TB) is an infectious disease that resulted in estimated 9.6 million new cases in 2014 and 1.5 million deaths. The available drug regimen for TB is time consuming which more often leads to the patient non compliance which then results in occurrence of drug resistant TB (Multi-drug and extremely drug resistant TB) in several portions of the world. The dangerous combinations of TB and HIV is taking its toll on human health. The foremost factor is non- profit associated with the development of anti TB drugs. There is almost 10 different drugs in various levels of trials whereas the vaccine development is focusing more on adult vaccine rather than a child vaccine. More than 15 vaccine candidate are in various stages of pipelines. Present compilation gives an account for various drug candidates and vaccine products in various stages of drug development. Also included is a recent collection of patents for assay methods, potential drug candidates/classes and vaccination products. The need is for improvement in the activity and chemical and biological description of under development compounds. Lastly the set up for clinical and appropriate uses for running a reliable clinical trial is a necessary prerequisite.

Clinical Pharmacology Considerations for Development of β Lactamase Inhibitor Combination with Antibiotics

The shrinking drug pipeline for antibacterial drugs has made it very precious to discover and develop novel drugs in this space. In this context, the recent approvals of β lactamase inhibitors with either cephalosporin or penem as combination drugs are welcome news to the community. There are number of β lactamase inhibitors with suggested partnered drugs that are currently in various stages of drug development. The focus of this manuscript is to provide some perspectives on clinical pharmacology considerations that may aid in the successful development of such combination drugs. In this regard, a broad framework which includes pharmacokinetics (PK), pharmacodynamics (PD) and PK/PD guided surrogate strategies are provided to enable an informed dosing decision of the combination agent.

An Evaluation of 20 Years of EU Framework Programme-Funded Immune-Mediated Inflammatory Translational Research in Non-Human Primates.

Aging western societies are facing an increasing prevalence of chronic inflammatory and degenerative diseases for which often no effective treatments exist, resulting in increasing health-care expenditure. Despite high investments in drug development, the number of promising new drug candidates decreases. We propose that preclinical research in non-human primates can help to bridge the gap between drug discovery and drug prescription. Translational research covers various stages of drug development of which preclinical efficacy tests in valid animal models is usually the last stage. Preclinical research in non-human primates may be essential in the evaluation of new drugs or therapies when a relevant rodent model is not available. Non-human primate models for life-threatening or severely debilitating diseases in humans are available at the Biomedical Primate Research Centre (BPRC). These have been instrumental in translational research for several decades. In order to stimulate European health research and innovation from bench to bedside, the European Commission has invested heavily in access to non-human primate research for more than 20 years. BPRC has hosted European users in a series of transnational access programs covering a wide range of research areas with the common theme being immune-mediated inflammatory disorders. We present an overview of the results and give an account of the studies performed as part of European Union Framework Programme (EU FP)-funded translational non-human primate research performed at the BPRC. These data illustrate the value of translational non-human primate research for the development of new therapies and emphasize the importance of EU FP funding in drug development.

Untapped Potential of Disordered Proteins in Current Druggable Human Proteome.

Current efforts in design and characterization of drugs often rely on the structure of their protein targets. However, a large fraction of proteins lack unique 3-D structures and exist as highly dynamic structural ensembles. These intrinsically disordered proteins are involved in pathogenesis of various human diseases and are highly abundant in eukaryotes. Based on a comprehensive analysis of the current druggable human proteome covering 12 drug classes and 18 major classes of drug targets we show a significant bias toward high structural coverage and low abundance of intrinsic disorder. We review reasons for this bias including widespread use of the structural information in various stages of drug development and characterization process and difficulty with attaining structures for the intrinsically disordered proteins. We also discuss future of intrinsically disordered proteins as drug targets. Given the overall high disorder content of the human proteome and current bias of the druggable human proteome toward structural proteins, it is inevitable that disordered proteins will have to raise up on the list of prospective drug targets. The protein disorder-assisted drug design can draw from current rational drug design techniques and would also need novel approaches that no longer rely on a unique protein structure.

Pharmacogenomics – The New Trend for Personalized Medicine

Pharmacogenetics and pharmacogenomics are two major emerging trends in medical sciences, which influence the success of drug development and therapeutics. In current times, though pharmacogenetic studies are being done extensively for research, its application for drug development needs to get started on a large scale. Pharmacogenetic studies can be used at various stages of drug development. The effect of drug target polymorphisms on drug response can be assessed and identified. In clinical studies, pharmacogenetic tests can be used for stratification of patients based on their genotype, which corresponds to their metabolizing capacity. This prevents the occurrence of severe adverse drug reactions and helps in better outcome of clinical trials. This can also reduce attrition of drug compounds. Recognition of inter-individual differences in drug response is an essential step towards optimizing therapy. Over the past decades, much evidence has emerged indicating that a substantial portion of variability in drug response is genetically determined, with age, nutrition, health status, environmental exposure, and concurrent therapy playing important contributory roles. To achieve individual drug therapy with a reasonably predictive outcome, one must further account for different patterns of drug response among geographically and ethnically distinct populations.

Incorporating clinical knowledge and experience in the evaluation of drug development projects using the analytic hierarchy process

Resource limitations require balancing factors such as efficacy, safety, market urgency, etc. to reach objective and consistent decisions at the various stages of drug development. Decisions about pursuing, delaying, or terminating a potential drug depend on the knowledge and experience of the product development team and the findings from completed experiments and trials. We describe how the analytic hierarchy process can be used to inform decisions, and illustrate its application to an actual development project. The dimensions of the decisions, the rankings of the possible outcomes for each dimension, and the rules for combining the components are determined by the key stakeholders before obtaining the determinative data. Laying out the rules before a product reaches a decision point facilitates exploration of the sensitivity of potential decisions to various assumptions. The process can be applied at any stage of clinical development. Its statistical properties can be evaluated using standard statistical decision analysis methods.

A Review of Biologic Therapies Targeting IL-23 and IL-17 for Use in Moderate-to-Severe Plaque Psoriasis.

The development of several highly effective biologic drugs in the past decade has revolutionized the treatment of moderate-to-severe plaque psoriasis. With increased understanding of the immunopathogenesis of psoriasis, the emphasis has turned toward more specific targets for psoriasis drugs. Although the complex immunological pathway of psoriasis is not yet completely understood, current models emphasize the significant importance of interleukin (IL)-23 and IL-17. Several biologic drugs targeting these cytokines are now in various stages of drug development. Drugs targeting IL-23 include BI-655066, briakinumab, guselkumab, tildrakizumab, and ustekinumab. Drugs targeting IL-17 include brodalumab, ixekizumab, and secukinumab. While many of these have shown safety and good efficacy in clinical trials of moderate-to-severe plaque psoriasis, long-term safety is still to be established.Electronic supplementary materialThe online version of this article (doi:10.1007/s13555-015-0092-3) contains supplementary material, which is available to authorized users.

The Cellular Thermal Shift Assay: A Novel Biophysical Assay for In Situ Drug Target Engagement and Mechanistic Biomarker Studies.

A drug must engage its intended target to achieve its therapeutic effect. However, conclusively measuring target engagement (TE) in situ is challenging. This complicates preclinical development and is considered a key factor in the high rate of attrition in clinical trials. Here, we discuss a recently developed, label-free, biophysical assay, the cellular thermal shift assay (CETSA), which facilitates the direct assessment of TE in cells and tissues at various stages of drug development. CETSA also reveals biochemical events downstream of drug binding and therefore provides a promising means of establishing mechanistic biomarkers. The implementation of proteome-wide CETSA using quantitative mass spectrometry represents a novel strategy for defining off-target toxicity and polypharmacology and for identifying downstream mechanistic biomarkers. The first year of CETSA applications in the literature has focused on TE studies in cell culture systems and has confirmed the broad applicability of CETSA to many different target families. The next phase of CETSA applications will likely encompass comprehensive animal and patient studies, and CETSA will likely serve as a very valuable tool in many stages of preclinical and clinical drug development.

Role of marine bioprospecting contracts in developing access and benefit sharing mechanism for marine traditional knowledge holders in the pharmaceutical industry

The remarkable growth of bio-based industry has led to a rapid increase in the bioprospecting activities. The marine biomes are a rich reservoir of unique life systems making them an attractive target for bioprospecting for identification and development of potential drug molecules for human therapeutics. Many of the drug molecules such as ara-c, trabecetidin and eribulin have been discovered from marine organisms. It is noteworthy that indigenous communities have developed, preserved as well as evolved the marine traditional knowledge from one generation to next. Pharmaceutical companies utilize marine life based traditional knowledge developed by the communities at various stages of drug development, unfortunately, many a times without having a mechanism of access and benefit sharing in place. One such example is the marine bioprospecting Fiji contract that illustrates the role played by Fijian community and the lacuna in access and benefit sharing mechanisms. The present study is an attempt to explore the mechanism of fair and equitable sharing of the benefits arising from use of marine bioresources with the local communities as marine traditional knowledge holders in marine areas. It briefly describes the various international conventions and protocols that emphasize on the development of fair and equitable benefit sharing mechanisms. The study proposes marine bioprospecting contracts that are based on mutually agreed terms among the key stakeholders (the State with the genetic resources, traditional knowledge holders and marine bioprospectors). Marine bioprospecting contracts eventually will need to be customized as per the legislation of a country because of territorial nature of law. Also, the marine bioprospecting contracts will differ from other bioprospecting contracts due to various unique parameters associated with the activity such as economics of deep sea explorations (expensive processes of exploration and sample extraction), continuous supply of sample, the jurisdiction of marine areas and traditional knowledge associated. The present study elucidates the concept of marine bioprospecting contracts by considering India as a case study emphasizing sharing of benefits with traditional knowledge holders as well as ensuring sustainable use of marine genetic resources by the pharmaceutical sector.

Designing of peptides with desired half-life in intestine-like environment.

BackgroundIn past, a number of peptides have been reported to possess highly diverse properties ranging from cell penetrating, tumor homing, anticancer, anti-hypertensive, antiviral to antimicrobials. Owing to their excellent specificity, low-toxicity, rich chemical diversity and availability from natural sources, FDA has successfully approved a number of peptide-based drugs and several are in various stages of drug development. Though peptides are proven good drug candidates, their usage is still hindered mainly because of their high susceptibility towards proteases degradation. We have developed an in silico method to predict the half-life of peptides in intestine-like environment and to design better peptides having optimized physicochemical properties and half-life.ResultsIn this study, we have used 10mer (HL10) and 16mer (HL16) peptides dataset to develop prediction models for peptide half-life in intestine-like environment. First, SVM based models were developed on HL10 dataset which achieved maximum correlation R/R2 of 0.57/0.32, 0.68/0.46, and 0.69/0.47 using amino acid, dipeptide and tripeptide composition, respectively. Secondly, models developed on HL16 dataset showed maximum R/R2 of 0.91/0.82, 0.90/0.39, and 0.90/0.31 using amino acid, dipeptide and tripeptide composition, respectively. Furthermore, models that were developed on selected features, achieved a correlation (R) of 0.70 and 0.98 on HL10 and HL16 dataset, respectively. Preliminary analysis suggests the role of charged residue and amino acid size in peptide half-life/stability. Based on above models, we have developed a web server named HLP (Half Life Prediction), for predicting and designing peptides with desired half-life. The web server provides three facilities; i) half-life prediction, ii) physicochemical properties calculation and iii) designing mutant peptides.ConclusionIn summary, this study describes a web server ‘HLP’ that has been developed for assisting scientific community for predicting intestinal half-life of peptides and to design mutant peptides with better half-life and physicochemical properties. HLP models were trained using a dataset of peptides whose half-lives have been determined experimentally in crude intestinal proteases preparation. Thus, HLP server will help in designing peptides possessing the potential to be administered via oral route (http://www.imtech.res.in/raghava/hlp/).Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2105-15-282) contains supplementary material, which is available to authorized users.

Innovations in Epilepsy Management – An Overview

In the past twenty years, thirteen new antiepileptic drugs (AEDs) have been introduced, each differing in their efficacy spectrum, mechanism of action, pharmacokinetics, safety and tolerability profiles. These newer AEDs symbolize a welcoming future in the management of epilepsy because they are able to produce a remarkable reduction in seizure frequency in up to 40% to 50% of the patients who had been refractory to old generation drugs. Despite the current availability of these new drugs, only a few patients with truly refractory seizures can be made seizure free. Although the newer agents are not superior to that of the older drugs, some have been shown to be non-inferior in terms of their efficacy. They offer additional advantages like better tolerability, ease of use, reduced interaction profile. Even though in most situations the older generation drugs still represent the best choice, advancing studies show that in many conditions, new generation drugs may be entirely vindicated for initial therapy. This urges a need for the search of novel and more efficacious new antiepileptic drugs in the management of uncontrollable seizures. More direct comparisons of newer versus newer and newer versus older drugs in clinical trials, both for monotherapy and adjunctive therapy must be conducted. More than 20 compounds with promising antiepileptic and neuroprotective properties have been discovered and are under various stages of drug development. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.

Effective visualization of integrated knowledge and data to enable informed decisions in drug development and translational medicine

Integrative understanding of preclinical and clinical data is imperative to enable informed decisions and reduce the attrition rate during drug development. The volume and variety of data generated during drug development have increased tremendously. A new information model and visualization tool was developed to effectively utilize all available data and current knowledge. The Knowledge Plot integrates preclinical, clinical, efficacy and safety data by adding two concepts: knowledge from the different disciplines and protein binding.Internal and public available data were gathered and processed to allow flexible and interactive visualizations. The exposure was expressed as the unbound concentration of the compound and the treatment effect was normalized and scaled by including expert opinion on what a biologically meaningful treatment effect would be.The Knowledge Plot has been applied both retrospectively and prospectively in project teams in a number of different therapeutic areas, resulting in closer collaboration between multiple disciplines discussing both preclinical and clinical data. The Plot allows head to head comparisons of compounds and was used to support Candidate Drug selections and differentiation from comparators and competitors, back translation of clinical data, understanding the predictability of preclinical models and assays, reviewing drift in primary endpoints over the years, and evaluate or benchmark compounds in due diligence comparing multiple attributes.The Knowledge Plot concept allows flexible integration and visualization of relevant data for interpretation in order to enable scientific and informed decision-making in various stages of drug development. The concept can be used for communication, decision-making, knowledge management, and as a forward and back translational tool, that will result in an improved understanding of the competitive edge for a particular project or disease area portfolio. In addition, it also builds up a knowledge and translational continuum, which in turn will reduce the attrition rate and costs of clinical development by identifying poor candidates early.

SGLT Inhibitors: a Novel Target for Diabetes

Inhibiting sodium-glucose co-transporters (SGLT1/SGLT2), which have a key role in the absorption of glucose in the kidney and/or GI tract has been proposed as a novel therapeutic strategy for diabetes. Thus, screening and patenting of chemical compounds for SGLT1/SGLT2 gets more importance in the development of new drugs in diabetes. Several companies are developing SGLT inhibitors, some of which are now in various stages of clinical development. Some molecules in the pipeline, including dapagliflozin, canagliflozin, ASP1941, BI10773, LX4211, RG7201 and TS071, are at various stages of drug development. This patent review presents the overall progress carried out in the development of SGLT inhibitors over the last decade with the active participation of various pharmaceutical companies. This class of drug is anticipated to have a large impact on diabetes field and predicting to attain a blockbuster status.

Selective VEGFR Inhibitors for Anticancer Therapeutics in Clinical Use and Clinical Trials

Angiogenesis and vasculogenesis, regulated by VEGF/VEGFR signaling pathways, play key roles in tumor growth and metastasis. Selective inhibition of VEGFR kinase has been explored as a highly successful clinical strategy in cancer treatment. A number of VEGFR inhibitors have been approved in clinical use and many more are in various stages of drug development. This paper reviews selective small-molecule VEGFR inhibitors in clinical uses and in clinical trials, with particular focus on in vitro, in vivo and clinical trial results of these inhibitors. The VEGF/VEGFR genes and signaling pathways involved in tumor angiogenesis, and the strategies for accessing and improving the therapeutic efficacy of VEGFR inhibitors are also discussed.

Multistage investment, systematic risk premium and CAPM beta: empirical evidence from product development

Recent theoretical literature suggests that the magnitude of the systematic risk premium for a multistage investment project is subject to various forces that may cause the premium to change across stages. To test this hypothesis, I investigate whether Capital Asset Pricing Model (CAPM) beta differs by product development stage in the biotechnology industry. To this end I estimate CAPM beta for various stages of drug development using Full-Information Beta (FIB) technique. Findings indicate that early stage drug development projects have higher CAPM beta than drugs in later stages of development or in production and marketing. The beta appears to decrease monotonically as a project approaches completion.

Dabigatran Etexilate in Clinical Practice: Confronting Challenges to Improve Safety and Effectiveness

A number of novel anticoagulants are moving through various stages of drug development. Recently, the United States Food and Drug Administration approved the oral direct thrombin inhibitor dabigatran etexilate to reduce the risk of stroke and systemic embolism in patients with nonvalvular atrial fibrillation. Although dabigatran offers a number of advantages over existing oral and parenteral anticoagulants, challenges exist for clinicians who must ensure its safe and effective use. Limited data are available on dabigatran use in patients with renal dysfunction and in obese patients, or in combination with other drugs. Clinical experience is lacking in populations for whom anticoagulants are routinely used, such as patients with a previous stroke, acute coronary syndromes, or pregnancy-associated thrombosis, or those requiring ablation therapy. More important, clinicians will be faced with incorporating dabigatran into hospital guidelines for transitioning between oral and parenteral anticoagulants, measuring anticoagulant intensity, managing anticoagulant-related hemorrhage, ensuring safe use around neuraxial anesthesia, and implementing computer-based alert or warning systems. Since anticoagulants are ubiquitously used in the prevention or treatment of venous and arterial thrombosis, both clinicians and patients must be provided structured education on dabigatran's benefits and limitations. In this article, our goal was to provide practical advice to enhance clinician understanding of dabigatran, identify clinical and operational challenges to its use, and offer system improvements that can ensure safe and effective use of dabigatran.