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Active projects

Active Projects

  • University of Washington - PK/PD modeling for anti-Shigella drug candidates

    Start : September 2017 | Status : Active

    The scientists:

    Dr. Samuel Arnold and Ms. McCloskey will focus their research on the setting up of an animal model of Shigella for assessing antibiotic efficacy and the integration of in vitro and in vivo data to generate a PBPK/PD model to enable the identification of novel anti-Shigella drug candidates. Samuel Arnold obtained his PhD in pharmaceutics from the University of Washington School of Pharmacy under the guidance of Dr. Nina Isoherranen. He has extensive background in pharmaceutical sciences including enzymology, pharmacology and clinical pharmacokinetics. He has recently contributed to the identification of gastrointestinal drug exposure as an important driver of anti-cryptosporidium drug efficacy.

    Molly McCloskey graduated with a Bachelor of Science in Biology from Saint Vincent College, Latrobe, Pennsylvania. Since then, she has studied cellular architecture and the molecular components involved in single cell wound healing. She currently works in the Van Voorhis lab at the University of Washington, working on developing therapies for cryptosporidiosis and aiding in research of other infectious diseases.

    The sponsor: University of Washington

    Foundation funding: The Foundation is providing £199,874 in support.

    GSK’s contribution: GSK will contribute its scientific expertise including DMPK support on lead drug candidates and access to PBPK/PD modeling resources.

    Project Description: The project focuses on drug discovery for Shigella. Main challenges in development of anti-shigella drugs are the lack of suitable animal models to evaluate compounds and the lack of information on PK/PD to anticipate in vivo efficacy and human dose.

    The first step in this project will be to test if the shigellosis B6 mouse model or other murine alternatives are suitable to evaluate antibiotics. Based on the localization of Shigella to the large intestine and the need to deliver antibiotics in GI tract, previous experience with PBPK-PD models to predict in vivo drug efficacy for anti-cryptosporidium drugs will be applied to predict in vivo efficacy of anti-Shigella compounds.

  • University of Melbourne - High throughput screening to identify selective proteasome inhibitors as new antimalarials with a novel mode of action

    Start : May 2017 | Status : Active

    The scientists:

    Dr. Stanley Xie is a postdoctoral researcher at the University of Melbourne, working under the supervision of Dr. Leann Tilley. He has extensive experience studying the P. falciparum proteasome and the mechanisms of action of and resistance to artemisinins. He will focus his research on identification and characterization ofnew hits acting through the P. falciparum proteasome.

    The sponsor: University of Melbourne

    Foundation funding: The Foundation is providing £198.239 in support.

    GSK’s contribution: GSK will support the project with its enzymology and high throughput screening platforms and contribute with its past experience working on the P. falciparum Ubiquitin Proteasome System. Additionally, GSK will also provide access to Biosafety Level 3 facilities and to GSK´s collection of proprietary compounds.

    Project Description: Current antimalarial control is highly dependent on Artemisinin-based Combination Therapies (ACTs), which makes the emergence of artemisinin (ART) resistance extremely concerning. This situation highlights the need to identify new drugs targeting different mechanisms in the parasite. The proteasome is a validated target for malaria. Inhibitors of the proteasome show parasiticidal activity against both ART sensitive and resistant parasites, and are active both against sexual and asexual intraerythroctyic stages, as well as liver stages. Moreover, the Leann Tilley lab has demonstrated that inhibitors of the proteasome strongly synergize ART-mediated killing of P. falciparum, being also suitable for combination therapies.

    The objective of this Open Lab project is to undertake a screening campaign to identify P. falciparum-specific proteasome inhibitors, thereby avoiding any toxicity associated with inhibition of the human proteasome. An extensive compound characterization will be performed, determining the parasitological profile and the mechanism of action applying tools developed in parallel during the project.

  • London School of Hygiene and Tropical Medicine - Optimization of imidazopyridine and thiazole scaffolds targeting plasmodial kinases to generate a fast killing compound to treat malaria infection and block transmission

    Start : January 2017 | Status : Active

    The scientists: Dr Alexios Matralis and Adnan Malik will work in the optimization of imidazopyridine and thiazole scaffolds targeting plasmodial kinases. Both researchers are medicinal/organic chemists with post-doctoral experience. Their main role will be the design, synthesis and characterization of the new compounds as well as the proposal of new ideas based on the acquired knowledge.

    The sponsor: London School of Hygiene & Tropical Medicine

    Foundation funding: The Foundation is providing £107,140 in support.

    GSK’s contribution: GSK will contribute its experience in phenotypic programs, medchem expertise, parasitology, in vitro assays, safety, and its in vivo humanized mouse model.

    Project Description: Starting from a set of compounds prepared by D. Baker’s group that showed activity in GSK phenotypic and dual gamete formation assays on top of its activity against P. falciparum cGMP-dependent protein kinase (PfPKG), this open lab will focus on improve the physchem profile of these families, increase their potency in the phenotypic/dual gamete formation assays, abolish toxicity issues, and gain knowledge of their in vitro killing profile in order to focus only in fast killing compounds. The aim of the project is to deliver compounds active in vivo in the P. falciparum mouse model, with physicochemical properties that allow developability and adequate safety profile.

  • University of Alabama at Birmingham - Self-poisoning of Mycobacterium tuberculosis by inhibiting siderophore secretion

    Start : July 2016 | Status : Active

    The scientists:

    Dr. Avishek Mitra, Bjorn Sunde and Prof. Michael Niederweis will focus their research on the identification of small molecules that kill Mycobacterium tuberculosis by inhibiting siderophore efflux. Dr. Mitra is a postdoctoral researcher working on iron acquisition by M. tuberculosis in the laboratory of Prof. Niederweis in the Department of Microbiology at the University of Alabama at Birmingham. Bjorn Sunde is a research assistant with experience in performing high-throughput screening assays in Biosafety Level 3 laboratories.

    The sponsor: University of Alabama at Birmingham, Department of Microbiology

    Foundation funding: The Foundation is providing £213,119 in support.

    GSK’s contribution: GSK will provide access to biosafety level 3 and high-throughput screening facilities, microbiology and drug discovery expertise as well as full access to antimycobacterial compound sets

    Project Description: Iron is an essential nutrient for M. tuberculosis which can acquire iron from heme and from its siderophores, mycobactin and carboxymycobactin. This project is based on the surprising finding that blocking siderophore secretion reduces the virulence of Mtb in mice by 10,000-fold. This is one of the strongest virulence defects observed for any Mtb mutant, probably due to the intracellular accumulation of siderophores. Externally added siderophores accumulate in the Mtb secretion mutant and are toxic at submicromolar concentrations. Importantly, this toxicity cannot be overcome by other iron sources such as heme in contrast to Mtb mutants deficient in siderophore biosynthesis. Since siderophore secretion spans both membranes, inhibitors might target this pathway from the outside of the cell and, thereby, might avoid the outer membrane permeability barrier of Mtb.

    We have developed a high-throughput screening assay that has identified inhibitors of Mtb whose activity depends on siderophores. These compounds are not detected in whole cell screens under standard conditions. Thus, siderophore secretion appears to be a valuable target for novel TB drugs that will be exploited in this project.

  • Structural Genomics Consortium - Identification of small molecule inhibitors targeting plasmodium methyltransferase SET1 and elongation factor 2

    Start : March 2016 | Status : Active

    The scientists:

    Dr. Cynthia Tallant is a Postdoctoral Researcher in the Chemical Biology Unit at the Structural Genomics Consortium (SGC), working under the supervision of Dr. Kilian Huber and Dr. Raymond Hui. She has a PhD in Structural Biology and Enzyme Kinetics and several years of experience as a PostDoc in these areas.

    The sponsor: The Structural Genomics Consortium, Structural and Chemical Parasitology lab (Oxford and Toronto).

    Foundation funding: The Foundation is providing £160,915 in support, including co-funding from the European Union through its FP7 COFUND programme.

    GSK’s contribution: GSK is providing scientific expertise in screening, enzymology, medicinal chemistry, in vitro parasite culture as well as access to Biosafety Level 3 facilities and to GSK´s collection of proprietary compounds.

    Project Description: The focus of the project will be the exploration of new antimalarial targets involved in parasite transcriptional regulation, such as the histone methyltransferase (HMT) SET1, and protein biosynthesis pathways controlled by the ribosomal translation elongation factor 2 (eEF2).

    A number of histone methyltransferase inhibitors have been shown to inhibit parasite growth in the intraerythrocytic cycle in both P. falciparum and P. vivax ex vivo experiments. Concomitantly, these same compounds were shown to reduce H3K4me3 methylation levels in parasites. Additional genetic studies in P. falciparum showed that some of these genes are essential for the parasite in the asexual blood stage.

    Recently, a novel antimalarial compound DDD107498 has been discovered and publicly discosed. This compound has excellent drug-like properties and exhibits a potent activity profile against multiple life-cycle stages of the parasite. Its molecular target has been identified as the translation elongation factor 2 (eEF2) using whole genome sequencing of resistant cell lines treated with DDD107498. This finding nominates PfEF2 as a novel antimalarial target.

    Together, the proposal aims to identify chemically diverse compounds targeting these two classes of enzymes, with activity against resistant mutants and inert to the human orthologues.

  • University of South Florida (USF), WRAIR and NIH - Antimalarial drug discovery targeting pre-erythrocytic stages of Plasmodium falciparum

    Start : TBD | Status : Set up ongoing

    The scientists: TBD

    The sponsor: University of South Florida (USF), WRAIR and NIH.

    Foundation funding: The Foundation is providing £352,939 in support.

    GSK’s contribution: GSK to share access to all generated data and provide access/use of compounds identified from the screen for further evaluation beyond the scope of this proposal. The Tres Cantos unit will provide in kind assay consumables and resources equivalent to two full-time personnel who will assist with gametocyte production, mosquito rearing and infections, dissections, imaging, data analysis, and support.

    Project Description: This project offers a major advance in antimalarial drug discovery by targeting pre-erythrocytic stages to block malaria infection. We have developed an innovative P. falciparum in vitro liver assay to evaluate drug toxicity and inhibitory efficacy of critical early phase of malaria infection in human hepatocytes. Consequently, this project can efficiently evaluate drug inhibition of the complete liver stage of the malaria life cycle. Central to this new screening strategy is a G384 microplate culture system using primary human hepatocytes (PHHs)(1) with modified P. falciparum sporozoite isolation procedures (2, 3). To enhance identification of the best lead compounds we will use quantitative functional assays of sporozoite entry into and egress from human hepatocytes along with transmission-blocking assays for mosquito infections. In developing our assays, we identified key microenvironmental triggers of infectivity that downstream can be used to elucidate target specificity and mechanisms of action.

    Altogether we provide a comprehensive new screening strategy for antimalaria drugs to block infection.

  • Sanger Institute - A chemogenomic overexpression screen to identify malaria liver stage targets

    Start : TBD | Status : Set up ongoing

    The scientists: TBD

    The sponsor: Sanger Institute.

    Foundation funding: The Foundation is providing £169,475 in support.

    GSK’s contribution: At early stages of the project GSK will provide significant input in shortlisting compounds for target identification and provide panels of compounds, as well as collaboratively prioritising targets of interest to be included in the screening panel of PACs. GSK will as well perform chemical re-synthesis of compounds if required. Later they will provide chemo-informatics expertise for data analysis. Targets for validation will be jointly decided. At a late stage of the project, targets with potential for cellular or recombinant enzyme screening will be selected. If compounds have the appropriate characteristics (solubility, DMPK properties, etc) validation work in mouse models will be done at Tres Cantos.

    Project Description: There is a widely recognised need for antimalarial drugs that target liver stages (1) but the paucity of suitable liver stage culture systems for human Plasmodium species has so far limited their development. Screening systems are now improving, and cellular screens have identified compounds that selectively kill this parasite stage, with the expectation that such compounds would have prophylactic potential. However, current screening assays have limited throughput. Identifying targets would allow target-based screens in a high-throughput format and explore millions of compounds. Because of the culture systems target ID cannot be achieved through conventional resistance selection approaches used so successfully with blood stage targets (2). In addition, the inefficiency (in the case of P. falciparum) or impossibility (in the case of P. vivax) of experimental genetics has so far prevented rational, target-led approaches to develop liver-active compounds. The strategy we propose here will therefore be potentially paradigm shifting, since it enables systematic screens for targets of liver-specific compounds for the first time.

    Genome-scale chemical-genetic interaction screens have successfully identified small molecule targets in libraries of diploid yeast (3-4) that carry heterozygous loss-of-function mutations in individual genes, sensitising their carriers to inhibitors of the same target or pathway. For malaria parasites, which are haploid, we here present evidence that chemical-genetic interaction screening can be used to identify targets not only at the blood stage but also in liver stages. Working with P. berghei, a parasite species that is uniquely suited to study liver stage biology in vitro, we have generated tools and methods to increase expression of parasite genes in a controlled and selective manner by introducing extra copies of the part of the genome that encodes them. We have created a library of Plasmodium artificial chromosomes (PACs) that can be transfected efficiently in pools during blood stages and are faithfully inherited through mosquito and liver stages. Our preliminary data show that treating cultured liver stages reproducibly shifts the relative abundance of individual PACs in accordance with known modes of action and modes of resistance, associating targets with compounds in an unbiased manner.

    Using this approach, we have defined the parameters for successful chemogenomic screening in liver stages. We propose here to apply the system to screen 24 liver-active compounds against 625 high priority targets. We will then work with GSK to select and follow up on the most interesting new targets by more detailed validation, cellular/recombinant protein assay development and target-based screens, which will be used to discover new chemical series for future development.

  • Seattle Children’s Research Institute & University of Washington - Identifying and inhibiting M. tuberculosis regulators that influence infection outcome

    Start : TBD | Status : Set up ongoing

    The scientists: TBD

    The sponsor: Seattle Children’s Research Institute.

    Foundation funding: TBD – just WP4 funded

    GSK’s contribution: In vivo and in vitro screening capacity available in Tres Cantos. Small molecule library for screening. Housing and lab space for one visiting scientist.

    Project Description: The goals of this project is to: 1) assess which M. tuberculosis (MTB) transcription factors (TFs) and regulons are important for survival during host infection; 2) define conditions under which these TFs are activated or deactivated; and 3) identify small molecules that inhibit their activity. To address these questions, we will: 1) screen for TFs that convey altered viability during infection when induced or disrupted in the chronic murine infection model; 2) develop screen based on reporter strains that will indicate TF-specific promoter activity; and 3) apply screen to a panel of conditions (including chemical inhibitors) to identify conditions that activate and deactivate individual TFs. The proposed approach is complementary to screens that have been run to date, as compounds with TF activity may be missed if MIC is the primary assay. TFs are a desirable target because their behavior is often switch-like, so successful targeting may be achieved with limited dosages and associated toxicities. Additionally, the known MTB transcription factors are structurally dissimilar to human TFs.

  • University of Washington - High Throughput Screening for Inhibitors of Shigella Virulence Determinants

    Start : TBD | Status : Set up ongoing

    The scientists: TBD

    The sponsor: University of Washington.

    Foundation funding: The Foundation is providing £145,204 in support.

    GSK’s contribution: Technical assistance with the inhibitor screen including help with instruments and software. Access to GSK’s small molecule libraries. Extensive communication and advice regarding screen design, execution, troubleshooting, and compound identification.

    Project Description: The primary goal of this proposed project is to test the hypothesis that small molecule inhibitors of Shigella transcription factors can promote the rapid resolution of infection. Previously, data collected from an in vivo transposon library screen (TN-Seq) using a guinea pig model of shigellosis was performed to provide a global view of genes and pathways that are critical for Shigella to survive and compete within the host.

    Disrupting the expression of these crucial genes and pathways with small molecule inhibitors is expected to result in severe defects in Shigella’s ability to colonize the host and cause disease. The proposed project will use high throughput assays to screen compound libraries for inhibition of pathways deemed to be essential for Shigella to survive in the host. Identified hits will be validated and tested for their capacity to functionally alter the course of Shigella infection using established in vivo models. If successful, this strategy could act as a blueprint for developing new drugs that target essential survival pathways in microorganisms, leading to an entire new class of treatments against infectious diseases.

  • University of California - Hit-to-Lead Development of the Kalihinol Scaffold for Malaria Treatment

    Start : TBD | Status : Set up ongoing

    The scientists: TBD

    The sponsor: University of California.

    Foundation funding: The Foundation is providing £172,190 in support.

    GSK’s contribution: The in-kind contributions from GSK will involve the characterization of simplified kalihinol analogues for their efficacy, safety, pharmacodynamics, and pharmacokinetics properties, initially to ensure that this series of compounds is as promising as our initial data suggest. In the medium term, further evaluations of these types will guide a medicinal chemistry effort for hit-to-lead development.

    Project Description: The ultimate goal of this collaborative research program is to identify antimalarial clinical candidates among analogues of the kalihinol family of isocyanoterpenes (Figure 1), an understudied class of natural products with potent activity against Plasmodium falciparum, the causative agent of the deadliest form of human malaria. Preliminary data generated in our laboratories support the premise of this research that the kalihinols could be developed as novel antimalarial agents. Our data demonstrate that (i) kalihinol natural products have potent activity against blood stages of both drug-sensitive and drug-resistant P. falciparum strains with IC50 values in the low nanomolar range; (ii) the synthetic route to these compounds has been simplified producing analogues that retain potent antimalarial activity, and there is a chemical plan in place for further synthetic simplification; (iii) the compounds have good HepG2 inhibition data and no major in silico safety alerts, and; (iv) they may exert their antimalarial activity through a novel mode of action. Building upon this body of data, we propose to delve deeply into the structure-activity relationship of these compounds, characterize their in vitro and in vivo efficacy and safety, and unravel their mode of action.

  • University of Zaragoza - TB antivirulence therapeutics: small molecule inhibitors against M. tuberculosis replication and persistence pathways as novel alternatives to classic antibiotics.

    Start : March 2019 | Status : Set up ongoing

    The scientists: TBD

    The sponsor: University of Zaragoza.

    Foundation funding: The Foundation is providing £153,435 in support.

    GSK’s contribution: The in-kind contributions from GSK will involve:

    • HTS using the GSK chemical library
    • Cytotoxicity, solubility, stability, …assays to define the value of identified compounds
    • Chemistry support for SAR and compound selection
    • Proteomics approaches
    • In vivo activity in a mouse model of TB virulence

    Project Description: Multidrug-resistant (MDR) and extensively drug-resistant (XDR) TB have alarmingly spread worldwide and make treatment difficult or even impossible. In addition, the one third of the human population latently infected with TB (LTBI) constitutes an enormous reservoir. Antivirulence therapies with small molecules that sabotage bacterial survival in the host may have advantages over traditional antibiotics because it targets factors required for pathogenesis, potentially reducing selection for resistance and limiting collateral damage to the resident microbiota (1, 2).

    Our project proposes a novel approach to disarm M. tuberculosis (Mtb), focused on searching antivirulence therapies against transcription factor PhoP as a paradigm regulon essential for Mtb virulence (3, 4). Recently, a small molecule inhibiting a transcription factor has been described to revert antibiotic resistance (5). We propose the construction of a reporter Mtb strain by placing strongly PhoP-regulated promoters (4) upstream GFP which will allow the screening of the complete GSK compound collection. Loss of GFP fluorescence upon treatment, indicative of selective virulence inhibition, can be easily monitored by high-throughput screening. Potential synergies between inhibitors, or between inhibitors and current anti-TB drugs will be assayed. We will confirm whether these compounds are active in macrophage and mouse models of TB and we also plan to assay the selected compounds against representative isolates of Mtb Complex lineages, which reflect the current genetic diversity of TB worldwide.

  • IBR-CONICET_UNR Instituto de Biología Molecular y Celular de Rosario - Trypanosoma cruzi bromodomains: druggable readers to look out!

    Start : March 2019 | Status : Set up ongoing

    The scientists: TBD

    The sponsor: Seattle Children’s Research Institute & University of Washington

    Foundation funding: The Foundation is providing £82,305 in support

    GSK’s contribution: GSK will give us access to a library of potential bromodomain inhibitors, as well to humans BRD proteins. On the other hand, GSK will let us introduce us in the field of high/medium throughput screening in which we lack expertise.

    Project Description: The discovery of new therapeutic options against Trypanosoma cruzi, the causative agent of Chagas disease stands as a fundamental need, since available drugs have significant toxic side effects and a variable efficacy against the life-threatening symptomatic chronic stage of the disease. Bromodomains are protein modules that bind to acetylated lysine residues. Their interaction with histone proteins suggests their role in interpreting the histone code. However, protein acetylation is not a phenomenon restricted to the nuclear proteins. Bromodomain-containing proteins are often found as components of larger protein complexes with roles in fundamental cellular process including transcription, cell cycle regulation, among others. In 2010 two BET bromodomains ligands were described demonstrating that small molecules could inhibit the bromodomain-acetyl-lysine interaction. These molecules display strong phenotypic effects in a number of cell lines and affect a range of cancers in vivo. Recent reports showed that bromodomain inhibitors affect T. cruzi viability and deregulate the expression of stage-specific proteins in T. brucei. The overall objective of this project is to search for bromodomain inhibitors in T. cruzi, by assaying essentials bromodomains previously established in a collaborative GSK-sponsored research project between Esteban Serra’s and Roberto Docampo’s labs. From this project three bromodomains from T. cruzi were selected as putative targets against Chagas disease.

  • University of Cambridge - High throughput small molecule screen for drugs that alter the shape of Campylobacter jejuni

    Start : TBD | Status : Set up ongoing

    The scientists: TBD

    The sponsor: University of Cambridge

    Foundation funding: The Foundation is providing £118,040 in support

    GSK’s contribution: GSK will contribute with high throughput screening expertise to miniaturize the assay. GSK will provide compounds for screening and access to Shigella animal models as well as drug discovery expertise to assess the potential of this approach to deliver a drug for patients.

    Project Description: The world faces a major infectious disease challenge that is being made worse by antimicrobial resistance. We need new therapeutic modalities that overcome resistance and that do not affect the natural gastrointestinal flora, which is proven to be essential for gastrointestinal health. We contend that cell shape may be a targetable Achilles heel for enteric bacterial pathogens and has not yet been fully exploited for drug discovery applications. There is evidence that cell shape can affect the virulence of pathogens (e.g. Campylobacter spp. and Salmonella spp.). Through this Open Lab project, this characteristic will be exploited for high-throughput screens against Shigella spp. and other enteric bacteria.

  • Research Agency of Aragon (ARAID) & University of Zaragoza (UNIZAR) - Predicting optimal dosing schedules and clinical outcomes of beta‐lactams for TB therapy using PKPD and mechanistic models Carbapenem vs. cephem: the beta‐lactam paradigm

    Start : April 2018 | Status : Set up ongoing

    The scientists: Santiago Ramón y María Pilar Arenaz

    The sponsor: Research Agency of Aragon (ARAID) & University of Zaragoza (UNIZAR)

    Foundation funding: The Foundation is providing £116,500 in support

    GSK’s contribution: GSK’s in kind contributions would be critical for the following: (i) Access to time-lapse microscopy and micro-pumping system to mimic PK profiles; (ii) imaging and analytical modeling software and skills; (iii) access to clinical data for modeling. In addition, based on previous experience (RIFACEPH project), the excellent scientific and personal support provided by GSK scientists would greatly facilitate the successful outcome of this proposal.

    Project Description: This proposal aligns and complements with current clinical trials now being explored by GSK DDW clinical partners. It also comes with additional funding that the applicant, Dr. Ramón-García, recently secured from the European Community for a 2-year project to be performed at GSK DDW.

    Carbapenems and cephems are beta-lactam (BLMs) antibiotics with different anti-tuberculosis (TB) killing properties and phenotypic responses that might affect therapy design for optimal clinical outcomes (Figure 1). Understanding the pharmacokinetic (PK) and pharmacodynamic (PD) parameters of BLMs alone and in combination with synergistic partners is critical if they are to be used for TB therapy (Figure 2). Similarly, the molecular determinants underlying synergistic interactions of BLMs with synergistic partner drugs are currently unknown. Elucidating the synergistic mode of action of such combinations will allow the design of novel strategies for TB therapy and help counteract the emergence of future resistance.

    To answer these questions, time-lapse microscopy, in vitro microbiology assays and transcriptomic studies will be leveraged to provide high quality molecular and pre-clinical data that, through mathematical PKPD modeling based on completed and ongoing GSK DDW BLM-containing TB clinical trials, will inform the design of future human combination trials with BLM components.Campylobacter spp. and Salmonella spp.). Through this Open Lab project, this characteristic will be exploited for high-throughput screens against Shigella spp. and other enteric bacteria.

  • EMBL- Unravelling new combinatorial therapies against Shigellosis

    Start : July 2018 | Status : Active

    The scientists: 2 FTE at EMBL

    The sponsor: EMBL

    Foundation funding: The Foundation is providing £116,800 in support

    GSK’s contribution: GSK will provide expertise with high throughput screening set ups and compound screening, as well as with data analysis. GSK will provide compound libraries and drug discovery expertise to assist in the compound selection. Materials for the experimental part performed at GSK will be provided in kind. GSK pharmacologist experts will support this project to unravel the PK/PD of synergistic combinations.

    Project Description: Combinatorial treatments provide an untapped, cost-effective source for new antibacterial treatments at a time where new therapies are urgently needed. Here we propose to establish a high-content microscopy platform for systematically screening drug combinations against intracellular Shigella. Shigellosis is one of the leading causes of diarrhea worldwide, with infections being more frequent and deadly in the developing world. The microscopy platform set up will not only facilitate high-throughput screening at the intracellular context of infection, where this pathogen has to be targeted, but will also provide insights into the mechanism-of-action of single drug(s) and the combinatorial treatment by monitoring the stage of infection and the host process(es) they affect. Using this platform, we will evaluate the impact of ~5,000 drug combinations during the course of infection in epithelial cells and macrophages. Strong synergies will be further evaluated in detailed surface response measurements (inhibition and killing curves – intracellularly and extracellularly), resistant and persistent assays. Last, prominent candidates will be moved to animal models and PK/PD measurements.

  • University of Michigan - Targeting Virulence Regulators as a Novel Approach to Antibiotics for Shigellosis

    Start : Nov 2018 | Status : Active

    The scientists: Marija Miljkovic

    The sponsor: University of Michigan

    Foundation funding: The Foundation is providing £81,085 in support

    GSK’s contribution: GSK will provide compounds for screening, consumables and expertise to perform the HTS and to select and prioritize the most promising hits. Biology and pharmacology support will be provided as well.

    Project Description: Diarrheal diseases, such as shigellosis, are the second leading cause of death in children under five years old. Many strains of Shigella spp. are drug or multi-drug resistant. Genetic knock-out studies of the Shigella virulence pathway controlled by the AraC-family transcription factor VirF (required for infection, cell-to-cell spread and escape from macrophages) show that inactivation of VirF or other virulence factors eliminates, or significantly reduces, pathogenicity. Importantly, expression of virulence factors is not required for Shigella viability; therefore, targeting virulence factors is expected to lower the risk for resistance development in Shigella while not affecting normal, avirulent colonic microbiota. We have identified 5 hits from an HTS of ~150,000 small molecules that inhibit VirF expression of a reporter gene and reduce the invasion efficiency of Shigella in in vitro models of infection. One of these hits blocks VirF binding to DNA. Our goal in this proposal is to identify novel and potent chemical matter that block Shigella virulence to conduct a ‘hit-to-lead” campaign. We will screen compounds from GSK’s 1.7M compound library, perform confirmation and secondary assays probing mechanism of action, PK/Tox and in vitro efficacy. Compounds that inhibit VirF•DNA binding will be co-crystalized with the VirF DNA binding domain to enable a structure-based hit-to-lead campaign.

  • University of Georgia + Bioaster - Chagas AABLO (Chagas AcylAminoBenzothiazol Lead Optimization)

    Start : Janurary 2018 | Status : Active

    The scientists: Charlotte Fleau

    The sponsor: University of Georgia + Bioaster

    Foundation funding: The Foundation is providing £159,226 in support

    GSK’s contribution: Chemistry labs for synthesis, purification, structure analysis. Full Profiling of Development pre-Candidate (ADMET2 and early toxicology).

    Project Description: T. cruzi is a protozoan parasite that causes Chagas disease, the highest impact infectious disease in Latin America. Although the host immune response is highly effective at controlling T. cruzi, the infection persists in most infected hosts. Previous work between our groups at The University of Georgia (UGA), Sanofi and BIOASTER has identified several Acyl-AminoBenzothiazol (AAB) hits with potent in vitro and in vivo toxicity for T. cruzi. These related hits came from an initial in vitro screen of a ~300,000 small molecule library by the Broad Institute (Pubchem AID: 1885); 171 of the ~3500 in hits with in vitro activity were selected for in vivo screening based upon druglikeness, potential for oral delivery and ease of synthesis and novelty. In a rapid in vivo efficacy assay, 5 of the 171 compounds showed strong activity – 3 of those 5 were in this AAB group. Subsequent in vitro SAR of 240 analogues revealed 3 AAB compounds with IC50 of <80 nM and identified the steps needed to optimize this compound class. Herein we describe the med chem plan for this optimization as well as for identification of the mechanism of action of these compounds. Paired with our unparalleled combination of in vitro and in vivo screening assays, and the prior evidence of in vivo efficacy of this compound class, we have an excellent opportunity to identify one or more compounds capable of providing parasitological cure.

  • Oxford University - Structural biology and assays enabling β-lactams that target Mycobacteria tuberculosis

    Start : July 2017 | Status : Active

    The scientists: Jurgen Brem – Mariska de Munnik

    The sponsor:Oxford University

    Foundation funding: The Foundation is providing £162,000 in support

    GSK’s contribution:
    - Determination of anti Mtb activity in vitro and in vivo. Oxford University does not have the capacity required for this work, therefore a collaboration with GSK TC is essential for the project.
    - Supply of compounds for testing in assays and structural evaluation (Note initial work will focus on compounds already available, with focused medicinal chemistry being the subject of a new funding application.)
    - Expertise in mechanistic chemistry (including modeling) to be used in inhibitor design possibly coupled to modeling
    - Assistance in project management including via frequent (Skype / phone) meetings
    - Expertise in identifying routes to pre-clinical and clinical candidates
    - A desire to work together to secure future large-scale funding to develop -lactam / analogous compounds to be used for Mtb treatment
    - The ability to work collaboratively with Oxford to rapidly follow up breakthrough results on new types of inhibitor.

    Project Description: β-Lactams, including penicillins, cephalosporins and carbapenems, remain the most important antibiotics in use for treatment of Gram- and Gram+ bacteria, but their use is compromised by growing resistance, most importantly due to widespread β-lactamase dissemination. Mycobacteria tuberculosis (Mtb) has a higher mortality rate than any other infectious disease; however, β-lactams have traditionally not been effective in Mtb treatment. The paradigm that β-lactams are not useful for treatment of Mtb (including XDR Mtb) is based on the poor cell permeability/stability/oral use of ‘classical’ β-lactams (which poorly penetrate the cell-membrane) and the presence of a genetically encoded β-lactamase (BlaC) in Mtb. This paradigm is now being questioned [1-3], because: (i) Recent clinical trials shows that meropenem combined with amoxicillin–clavulanic acid has potential for treating Mtb; (ii) Carbapenems not only inhibit Mtb D,D-transpeptidases, but can also Mtb inhibit L,D-transpeptidases ; (iii) Clinically used cephalosporins in combination with clavulanic acid manifest synergistic effects in Mtb treatment; (iv) novel cephalosporins with C-2 carboxylate isosters have shown selective activity against non-replicating Mtb [3]. Thus, the timing is right for focused efforts to develop tailored β-lactams for Mtb treatment together BlaC inhibitors, the latter being the initial focus of our proposed work.

    Such work will be enabled by contemporary availability of: (i) New types of transpeptidase / β-lactamase inhibitors, including new acylating agents, such as those based on avibactam and lactivicins [9], and ‘transition state analogues’ e.g. cyclic boronates that display remarkable potency against β-lactamases [5]; such compounds have potential as transpeptidase inhibitors with very different PK/PD properties compared to classical β-lactams; (ii) Extensive new structural and mechanistic information on β-lactam mode of action and resistance mechanisms has emerged since the classical β-lactams were developed; (iv) New synthetic methodologies enable access to complex densely functionalised rings systems (e.g. functionalized oxapenems) previously unviable due to ‘cost of goods’ issues; (v) Knowledge of (Mtb infected) human cell biology will enable more rational targeting of β-lactams to Mtb in human cells. The focus of this OpenLab project will be structural, screening, and mechanistic work (including involving new inhibitors types) that will enable future medicinal chemistry efforts to enable clinically useful BlaC resistant PBP inhibitors for oral Mtb treatment.

  • Oxford University Clinical Research Unit - Hit discovery for new antimicrobials against Shigella spp.

    Start : April 2017 | Status : Active

    The scientists: Andrew Lim – Phat Voong Vinh

    The sponsor:Oxford University Clinical Research Unit

    Foundation funding: The Foundation is providing £174,038 in support

    GSK’s contribution: GSK will provide facilities for HTS and compound collections to be screened. In addition, GSK will provide resources in kind for DMPK and safety profiling of the interesting hits identified.

    Project Description: Our ultimate aim is to develop new drugs for the treatment of infections caused by Shigella spp. (a major cause of diarrhea in low-income countries) that work through novel mechanisms of action. Within this open-lab application we aim to carry out the following:

    • Phenotypic screening against Shigella sonnei and Shigella flexneri 2a using chemically diverse compound libraries under a variety of conditions aiming, where possible, to mimic physiological conditions
    • Screening compound libraries against AMR isolates in the presence of antimicrobials to which they are resistant, aiming to identify compounds that restore antimicrobial activity
    • Compound hits will be validated through assay against panels of clinical isolates, including newly emergent MDR strains
    • Validated hits will be profiled in various in vitro DMPK assays, such as solubility and metabolic stability. Preliminary safety assessment in silico and in vitro will be additionally performed, as well as hit expansion

  • Biomedical Primate Research Centre - Optimization of hepatocyte culture to support drug screening for malaria hypnozoites

    Start : May 2017 | Status : Active

    The scientists: Anke Harupa – Lars Vermaat

    The sponsor:Biomedical Primate Research Centre

    Foundation funding: The Foundation is providing £141,552 in support

    GSK’s contribution: We envisage GSK’s contribution in the field of hepatocyte culture, which will be of great value to the project. The Open Lab scientist will perform part of the hepatocyte culture optimization at GSK facilities, GSK will provide consumables for these periods in kind as well as mentoring from experienced researchers.

    Project Description: The BPRC P. cynomolgi in vitro liver stage drug assay, enabling drug screening on developing- and dormant liver stages (hypnozoites), may be biased towards prophylactic compound activity, rather than radical curative activity. The assay is performed with primary rhesus monkey hepatocytes and drug exposure from day 0 to 6 days post sporozoite infection. We are currently developing an assay that may be more predictive for radical curative activity, by applying compound exposure from day 5 to 9 post infection. Primaquine (PQ), the only positive control with known radical curative activity in vivo, has variable activity in the standard assay and no activity in the radical cure type assay. Thus, we are lacking a positive control in the assay. As PQ needs to be metabolized to display anti-hypnozoite activity, it is likely that declining metabolic activity over time of the primary hepatocytes causes this variable activity in the standard assay and absence of activity in the radical cure type assay. We plan to address this by first fully characterizing hepatocytes during culture and in the liver prior to isolation. This includes typical hepatocyte markers as well as the metabolism capacity. We will then apply alternative culture methods and monitor PQ metabolism over time. Finally, we will monitor parasite invasion and growth and PQ anti-parasite activity over time, and adapt culture conditions further to arrive at an optimal radical cure type assay. Once the radical cure assay is optimized, a set of compounds will be screened, using PQ as the positive control, aiming to identify novel compounds with radical cure activity.

  • Utrecht University - Attacking Shigella by blocking its disease causing Toxin

    Start : October 2017 | Status : Active

    The scientists: Jie Shi – Torben Heise

    The sponsor: University of Utrecht

    Foundation funding: The Foundation is providing £152,256 in support.

    GSK’s contribution:

    • Use of premises (space), associated site costs and shared service support
    • Lab supplies at GSK
    • Pre-clinical development services (in vivo studies, Chem Dev, Pharm Dev)
    • Access and support from a “GSK mentor” throughout the duration of the project
    • Support from other scientists as project needs.

    Project Description: Our approach towards Shigella involves the Shiga toxin as its target. This toxin causes serious disease,and is clearly on the rise in the dominant Shigella species in the developing world. It is an AB5 toxin that binds to multiple copies of a carbohydrate moiety expressed on the cell surface. We intend to design and synthesize the optimal binding moieties for toxin binding. These designs are based on our previously successful rigid spacer design for bridging binding sites and on our approach to inhibit the related Cholera AB5 toxin at picomolar concentrations. The focus is on intercepting the toxin in the blood stream. The Shiga toxin is an excellent target as it should be amenable to very potent inhibition and a demonstration of in vivo susceptibility has already been made. We intend to design and synthesize the compounds in Utrecht (UU) and explore their potency and activity at OL.

  • University of Georgia - Rapid selection of in vivo active anti-Trypanosoma cruzi compounds

    Start : July 2016 | Status : Active

    The scientists: Dr. Alba Gigante is an organic/ medicinal chemist by training, with experience working in neglected diseases. Currently she is a Postdoctoral Researcher working with Prof. Rick Tarleton from the University of Georgia. Her primary role in this project is to identify novel phenotypic leads against Trypanosoma cruzi from the TCAKS_CHAGAS set (Tres Cantos Anti Kinetoplastid Set). During her stay in Tres Cantos she will perform analog searches within GSK library for the in vivo active hits as well as the design of convergent synthetic routes for further SAR enrichment.

    The sponsor: University of Georgia

    Foundation funding: The Foundation is providing £189,705 in support.

    GSK’s contribution: GSK will contribute with solid availability for compounds in the TCAKS_CHAGAS set (Tres Cantos Anti Kinetoplastid Set) as well as analogue searching within the GSK collection. GSK will contribute in-kind its drug discovery expertise supporting the design of new analogues as well as completing preliminary compound profiling (in vitro T.cruzi, in vitro ADMET)

    Project Description: T. cruzi is a protozoan parasite that causes Chagas disease, the highest impact infectious disease in Latin America. Previous work at Tres Cantos has identified a total of 222 small molecule prioritized according to their potency against T.cruzi, cytotoxicity, and physico-chemical properties, called TCAKS-Chagas. The purpose of this project is to determine which among these prioritized in vitro-active compounds also has substantial in vivo activity on T. cruzi, and thus promise as a hit for lead compound development.

    The investigators from University of Georgia, led by Prof. Rick L. Tarleton, have developed a facile and rapid assay that makes use of transgenic T. cruzi lines expressing fluorescent proteins, which allows imaging the establishment and expansion of these tagged parasites after a single administration of compound, and hence determine in vivo efficacy of a number of compounds (up to 30 at a time) in < 1 week. This rapid in vivo assay seems to be an excellent predictor of long-term efficacy and is thus a potent screening method for selection of candidates for subsequent studies.

  • Research and Development Agency of Aragon (ARAID) Foundation - Shortening and improving compliance to Buruli ulcer therapy- Four weeks daily triple betalactam (Europe)

    Start : June 2020 | Status : Active

    The sponsor: Research and Development Agency of Aragon (ARAID) Foundation

    Foundation funding: The Foundation is providing £507,601 in support.

    GSK’s contribution: GSK will provide in-kind scientific and statistical support in the development and delivery of the project; dependent on the needs identified by the investigators and the available GSK expertise.

    Project Description: T. cruzi is a protozoan parasite that causes Chagas disease, the highest impact infectious disease in Latin America. Previous work at Tres Cantos has identified a total of 222 small molecule prioritized according to their potency against T.cruzi, cytotoxicity, and physico-chemical properties, called TCAKS-Chagas. The purpose of this project is to determine which among these prioritized in vitro-active compounds also has substantial in vivo activity on T. cruzi, and thus promise as a hit for lead compound development.

    Buruli ulcer (BU) is a chronic debilitating skin and soft tissue mycobacterial infection that without treatment frequently progresses to massive ulceration. The greatest burden falls on children under the age of 15 years in sub-Saharan Africa. This neglected tropical disease generally affects poor communities in remote rural areas with limited access to health services. Although mortality is low, permanent disfigurement and disability are high, affecting up to 25% of the cases. Before 2004, surgical excision and skin grafting remained the mainstay of BU treatment until clinical evidence showed the effectiveness of rifampicin-streptomycin; however, serious adverse events associated to the injectable streptomycin and the lack of an efficacious oral treatment remained one of the main obstacles to decentralizing care in rural areas. Today, WHO recommends an 8-week full oral daily combination therapy of rifampicin-clarithromycin; however, access to medicines is difficult, and the need of hospitalization for treatment impacts household’s income and compromises patients’ adherence to the 8-weeks antibiotic course. A shortened, highly effective, all-oral regimen based on already approved drugs is urgently needed to improve care for this neglected tropical disease by reducing both duration of treatment and time to healing for all type of lesions after therapy completion; this would in addition reduce indirect costs and barriers to access therapy. Similar to Tuberculosis (TB), rifampicin is the cornerstone drug for BU therapy, showing a direct relation between dose increase and therapy efficacy due to its bactericidal and sterilizing activity. High-dose rifampicin studies suggested that BU treatment could be shortened if rifampicin dose was increased. However, this approach raises concerns due to high-dose rifampicin-related hepatotoxicity and public health implementation. It would be then desirable to maintain current dose and potentiate the activity of rifampicin avoiding its side effects. In addition, TB chemotherapy teaches us that combination therapy is critical for optimal cure outcomes and treatment shortening, suggesting that at least a three-drug regimen might be needed to improve and shorten BU treatment. In fact, synergistic partners could improve rifampicin efficacy without compromising tolerability and toxicity. Beta-lactams are one of the largest groups of antibiotics with an exceptional record of clinical safety. Recent studies from partners of this Clinical Study Protocol (CSP) provided evidence of their anti-mycobacterial clinical potential, opening a new avenue to optimize current BU therapy. We thus took advantage of knowledge gathered in TB Research and Development (R&D) repurposing programs and showed in in vitro preclinical studies that beta-lactams strongly increased the activity of rifampicin and clarithromycin against Mycobacterium ulcerans (Mul). We further confirmed these observations by time-kill kinetics. Among all beta-lactams, we focused on amoxicillin/clavulanate: oral, suitable for the treatment of children, pregnant women and adults and with a long track record of clinical pedigree. First launched in the UK in 1981, today it is clinically available in various formulations in over 150 countries around the world. The addition of amoxicillin/clavulanate to current WHO recommended therapy could contribute to treatment shortening in several ways:

    • The median time to healing is directly proportional to the bacterial load in BU lesions at the beginning of therapy. Typically, healing occurs within 25 weeks from the start of treatment but for some BU patients this can take up to one year. One of the reasons for this slow healing could be a high initial bacterial load, since bacteria have been found in slowly healing lesions despite the recommended 8- week antibiotic therapy.
    • Despite antibiotic efficacy, the most common treatment complication of BU patients in Africa is paradoxical reaction, a phenomenon observed following an initial period of clinical improvement characterized by worsening of existing lesion(s) and occurrence of new ones during or after antibiotic therapy due to unspecific immune responses. Importantly, fast bacterial clearance reduces the rate of paradoxical responses. Due to its rapid bactericidal activity, amoxicillin/clavulanate would be extremely effective at targeting extracellular bacteria; thus, reducing initial bacterial burden, paradoxical responses, local levels of the immune-suppressive mycolactone toxin, and allowing recovery of the host immune response to clear remaining bacteria.
    • What is more, in vitro studies have demonstrated the sterilizing activity of synergistic combinations of beta-lactams and rifampicin, these could target the remaining persistent populations having a positive impact in treatment and healing periods.

    In this study, we propose the combination of amoxicillin/clavulanate with current oral BU therapy, rifampicin and clarithromycin as a new anti-BU treatment with the potential of treatment shortening and readily implementation in the field.

  • Research and Development Agency of Aragon (ARAID) Foundation - Designing optimal regimes for tuberculosis therapy using one-step high content dynamic in vitro kill kinetic assay linked to hollow fiber studies (Europe)

    Start : June 2020 | Status : Active

    The scientists: Maria Pilar Arenaz (2nd scientist: TBD)

    The sponsor: Research and Development Agency of Aragon (ARAID) Foundation

    Foundation funding: The Foundation is providing £174,142 in support.

    GSK’s contribution: GSK R&D contribution has been, so far, critical for the successful development of the former TC256 project, leading to this current proposal. We envision GSK R&D contribution to this new project as a continuation of current scientific and operational support that can be structured within several main activities:

    • Access to compounds and screening infrastructure: the microplate reader EnVision is critical to meet the throughput requirements of the project in a timely manner.
    • Mass spectroscopy analytical capacity to characterize the medium degradation kinetics of drugs used in the OPTIKA screening and drug concentrations in the different hollow fiber compartments.
    • Data analysis and modeling support to integrate PD (in vitro activity) and PK (drug degradation) drug’s parameters.
    • Data analysis and modeling support to integrate data generated under this project proposal with currently available preclinical and clinical data and to develop a machine learning/AI model to predict up to 4-way drug interactions.
    • Capacity to perform murine in vivo models of Mtb infection to evaluate drug combinations.

    Project Description: Recent years have seen a resurgence of new drug-like chemical entities with anti-ycobacterial activity, a number of which progressing into clinical trials. Understanding how to develop these compounds into therapeutically effective multi-drug regimens remains, however, an unresolved question. Traditional efforts to identify new potential drug combinations involve empirical phenotypic screening for in vitro synergies at the microbiological level. This is typically done by checkerboard assays (CBA) able to interrogate 2-way drug interactions but with limited power to identify 3-way or higher order drug interactions. A new technology called DiaMOND (diagonal measurement of n-way drug interactions) has overcome this limitation by reducing the number of interactions that require testing and vastly simplified the ability to identify favourable combinations of 3, 4 or even higher number of drugs. However, both CBA and DiaMOND remain inherently rooted in the use of the Fractional Inhibitory Concentration Index (FICI), a measurement of growth inhibition, as the metric of drug activity, rather than bacterial killing, which remains unmeasured. In addition, any synergistic combinations identified by FICI-based readouts require secondary validation by time kill assays (TKA) that significantly, and in some cases prohibitively, increase the complexity and duration of combination testing. TKAs are the most valuable assay in static in vitro pharmacokinetic (PK) and harmacodynamics (PD) studies and rely on Colony Forming Unit (CFU) enumeration at different time points (instead of a fixed time point as in the case of CBA or DiaMOND). TKAs are also the basis of mathematical modelling of antimicrobial drug action; however, TKA throughput in Mtb is typically limited to the working capacity of the technical operator, ca. 30 samples; this limited throughput capacity creates a barrier when it comes to validate 3 or higher n-way interactions. During the course of project TC256, we developed a new methodology named OPTIKA (Optimized Time Kill Assays, described below) that increased the capacity of traditional TKAs by more than 30-fold. OPTIKA allows facile high throughput interrogation of n-way drug interactions that are also dynamic and include direct measures of cidality. In doing so, we can now more rapidly and rigorously identify new potential triple drug interactions by coupling OPTIKA to in vivo studies and dynamic PKPD models using the Hollow Fibre System for Tuberculosis. The goal of this project is thus to provide robust preclinical evidence to suggest new therapeutic regimen options for TB treatment.

  • Public Health England - Optimisation of a screen for antimicrobials that enhance pyrazinamide activity against Mycobacterium tuberculosis (Europe)

    Start : June 2020 | Status : Active

    The scientists: Jordan Pascoe

    The sponsor: Public Health England

    Foundation funding: The Foundation is providing £95,787 in support.

    GSK’s contribution: GSK provide expertise on the development of antibiotics for the TB drug pipeline and also expertise in HTS, the screening of compound libraries, and staff time in training and supervising the project work to be completed at GSK. GSK provide the compound libraries for us to screen in the project and will test the efficacy of the selected candidates in vivo and enable a pathway to development of successful candidates. GSK will provide all the consumables, supervision, and equipment required for the screening, toxicity, and murine studies to be carried out at GSK.

    Project Description: An important aim for improving TB treatment is to shorten the period of antibiotic therapy without increasing relapse rates or encouraging the development of antibiotic-resistant strains. PZA is a key component of front-line chemotherapy against Mycobacterium tuberculosis. It plays an essential role in the shortened 6-month treatment course [due to its ability to act upon the non-replicating/slow-growing or antibiotic resistant organisms that emerge following treatment with the other front-line drugs, isoniazid (INH) and rifampicin (RIF). Although new combinations of antibiotics with novel modes of action are being evaluated, optimal dosing and treatment duration can be investigated further for existing antibiotics. Potentiation of frontline drugs is an approach that can extend the life of existing antibiotics, such as PZA. PZA has no detectable early bactericidal activity (EBA) in the first 2 days of treatment [3]. However, despite this lack of efficacy, PZA exerts an effect by shortening treatment only during the first 2 months of treatment and not beyond this. Extending the duration of treatment with PZA has no additional benefit in either humans or murine models. Can we be sure that PZA is not active during the early stages of treatment? It has always been assumed that INH clears the fast-growing population during EBA leaving non-replicating/slow growing drug-tolerant bacteria that need to be cleared by other drugs such as PZA. However, in a recent study we showed that both fast and slow growing cells persist through INH exposure and via different growth rate-specific genotypic and phenotypic mechanisms. Therefore, we cannot generalise that fast-growing bacteria are sterilised during EBA and slow growing cells are sterilised later during treatment. The contribution of PZA to the clearance of actively-dividing bacteria during the first phase of treatment has not been fully explored but it may be having hidden and profound effects such as controlling bacterial numbers or preventing antibiotic resistance from arising. Could the activity of PZA be improved during the first phase of treatment by using it in combination with other antibiotics that boost its activity; thereby further shortening treatment times? The goal for PHE is to discover potentiators that enhance the activity of PZA and have the potential to shorten TB treatment.

    Aims

    1) Identify candidate potentiators from compound libraries that enhance PZA activity

    2) Further characterise these candidates for specificity in their potentiation of PZA

    3) Select compounds for in vivo assessment that show PZA-specific potentiation, low mutant frequency, activity against a range of relevant bacterial phenotypes, reversion of PZA resistance in clinical strains, low toxicity

    4) Perform in vivo assessment of efficacy

  • IMM Lisboa - Generation, characterization and in vivo evaluation of a novel live malaria vaccine (Europe)

    Start : December 2019 | Status : Active

    The scientists: Patricia dos Santos

    The sponsor: Instituto de Medicina Molecular Lisboa

    Foundation funding: The Foundation is providing £147,121 in support.

    GSK’s contribution: GSK contribution to the project will include providing the humanized mouse models to be employed in the project, as well as the technical expertise, equipment and reagents to assess the parasite’s ability to infect and develop in human and mouse red blood cells. This project will synergize with ongoing efforts of the GSK-DDW group, as the liver stage of Plasmodium infection has been considered a strategy priority of the unit. A follow up of the successful open Lab TC111 is planned for 1Q19 in order to transfer and implement an optimized pseudo liver-mouse model.

    Project Description: Malaria remains the most prevalent parasitic disease for which a vaccine is still not available. So far, whole-sporozoite (Wsp) vaccines have shown most success among current candidates. The applicant’s lab has defined and established the proof-of-concept of a novel approach to Wsp malaria vaccination, based on the use of non-pathogenic rodent malaria parasites, genetically engineered to express antigens of their human-infective counterparts. PbVac, a Plasmodium berghei (Pb) parasite that expresses the P. falciparum (Pf) circumsporozoite protein is the first member of this new class of vaccine candidates. PbVac has demonstrated high safety profile and significant immunizing efficacy in recent phase I/IIa clinical trials. Stemming from these encouraging results, we now propose to generate and evaluate a new transgenic Pb parasite with enhanced immunogenicity and efficacy against Pf infection. To this end, we will engineer a Pb parasite line that expresses multiple antigens of the human-infective Pf parasite, we will characterize the expression of the inserted transgenes, and we will define its infectivity both in the mosquito vector and in the mammalian host. In order to ensure the safety and regulatory compliance of the newly generated Pb-based immunization agent, we will make use of GSK-DDW’s blood-humanized (BH) mouse model to pre-clinically assess lack of infection of human (Hu) red blood cells (RBC) by these parasites. This is a pivotal step in the definition of the parasite’s safety profile and a crucial requirement for the regulatory approval of its clinical use.

  • University of Dundee - Design of novel inhibitors of Shigella LpxC (Europe)

    Start : October 2019 | Status : Active

    The scientists: Pending

    The sponsor: University of Dundee

    Foundation funding: The Foundation is providing £293,009 in support.

    GSK’s contribution: GSK has developed both extra-cellular assays for Shigella and also intracellular assays, both in Caco2 cells and macrophages (THP1 cells). These assays will be used to assay compounds for whole cell activity. In addition, GSK has the possibility to run most promising hits in a panel of enteric bacteria (E.g. Salmonella, E. coli, Campylobacter) including drug-sensitive and MDR organisms. For key compounds, screening against a panel fo Gram-negative and Gram-positive bacteria. GSK has already identified LpxC inhibitors with activity against Shigella, and they can provide this expertise. The in-kind contributions from GSK will also be involve in the characterization of promising hits (in vitro profiling). In the medium term, further evaluations of these types will guide a medicinal chemistry effort for hit-to-lead development.

    Project Description: Shigellosis is a major cause of diarrhea in Low and Middle Income Countries and is responsible for hundreds of thousands of deaths each year. Drug resistance is a major problem and there is a need for new drugs with novel modes of action to tackle this terrible disease. Furthermore, the complex array of Shigella species and serotypes may make vaccine development challenging. The aim of this project is to develop novel inhibitors of LpxC as potential agents for the treatment of shigellosis. A recent screen carried out in GSK against whole cell bacteria has validated this as a drug target in Shigella. LpxC is a zinc metalloprotein responsible for de-acetylation of an advanced precursor to Lipid A. A number of different organizations have worked on LpxC inhibitors; the majority of disclosed inhibitors of LpxC are based on hydroxamic acid analogues, which suffer from poor pharmacokinetics and toxicity issues. No hydroxamate based LpxC inhibitor has reached the clinic. Our aim is to use a structure-based approach to find non-hydroxamate-based inhibitors of Shigella LpxC. To achieve this, we will screen with a series of Zn binders, identified from the literature and protein data bank (pdb). We aim to explore a wide range of zinc binding groups. We wil also explore the possibility to use benzoxaboroles as new Zn binders (exploiting the ability of zinc to activate a water molecule to generate active Zn binders as reported in DDU recent publication: PNAS, 2018, vol. 115,no. 38, 9616–9621). As well as finding non-hydroxamate Zn binders, we also aim to exploit the relatively weakly explored UDP-binding region of the enzyme, which should allow us to develop novel scaffolds. We will screen using our fragment library. There is a lot of structural information from the literature and the pdb we could then utilize to guide optimization. Final goal for this proposal is to find a non-hydroxamate zinc binding motif for LpxC and to carry out a fragment-based optimization to find inhibitors that are active in a cellular model.

  • University Hospital Tübingen - Microbiome restoration therapeutics for environmental enteric dysfunction (EED) and associated stunted childhood growth

    Start : November 2019 | Status : Active

    The scientists: Nermin Akduman

    The sponsor: University Hospital Tübingen

    Foundation funding: The Foundation is providing £215,576 in support.

    GSK’s contribution: The project would immensely benefit from the exceptional setting of the Tres Cantos Open Lab Foundation, allowing access to topnotch expertise in screening and drug development and connections to a network of experts in the EED field. Furthermore, an ‘Open Lab’ collaboration would offer a unique opportunity to conduct a pioneering and innovative study on microbiome modulating therapeutics with broader impact, as the presence of members of the oral microbiome at distant body sites is not restricted to EED alone but also typical for other inflammatory diseases including colorectal cancer and rheumatoid arthritis.

    Project Description: Environmental enteric dysfunction (EED) is a poorly understood inflammatory syndrome characterized by reduced absorptive capacity and barrier function in the small intestine. It is widespread among children in low-income countries and impairs child growth and development (stunting). Although various infectious agents have been suggested to cause EED, recent evidence supports the idea that a “decompartmentalization” of intrinsic throat microbes towards the small intestine combined with a depletion of beneficial butyrate-producing microbes sustains inflammatory conditions. Effective treatment strategies such as microbiome modulation to revert this imbalance are still missing. The overarching goal of this study is to identify lead compounds, drugs or drug/food combinations that modulate the gastrointestinal microbiome in stunted children towards a healthy microbial community. To this end, we propose screening for inhibitors of EED-related taxa from the oropharynx and for growth enhancers of protective microbes. This endeavor will profit from both, GSK’s compound libraries, expertise and screening platforms as well as from our recently established anaerobic high-throughput platform that is perfectly geared towards the needs of fastidious EED-related microbes. Promising candidates/combinations will be followed up in vitro with EED-mimetic microbial communities and in vivo using EED gnotobiotic mouse models. Successful microbiome modulators have tremendous potential to resolve EED’s inflammatory conditions with crucial impact on growth and development of young children around the world.

  • University of Washington - PK/PD modeling for anti-Shigella drug candidates (America)

    Start : September 2017 | Status : Active

    The scientists: Dr. Samuel Arnold and Ms. McCloskey will focus their research on the setting up of an animal model of Shigella for assessing antibiotic efficacy and the integration of in vitro and in vivo data to generate a PBPK/PD model to enable the identification of novel anti-Shigella drug candidates. Samuel Arnold obtained his PhD in pharmaceutics from the University of Washington School of Pharmacy under the guidance of Dr. Nina Isoherranen. He has extensive background in pharmaceutical sciences including enzymology, pharmacology and clinical pharmacokinetics. He has recently contributed to the identification of gastrointestinal drug exposure as an important driver of anti-cryptosporidium drug efficacy. Molly McCloskey graduated with a Bachelor of Science in Biology from Saint Vincent College, Latrobe, Pennsylvania. Since then, she has studied cellular architecture and the molecular components involved in single cell wound healing. She currently works in the Van Voorhis lab at the University of Washington, working on developing therapies for cryptosporidiosis and aiding in research of other infectious diseases.

    The sponsor: University of Washington

    Foundation funding: The Foundation is providing £199,874 in support.

    GSK’s contribution: GSK will contribute with its scientific expertise including DMPK support on lead drug candidates and access to PBPK/PD modeling resources.

    Project Description: The project focuses on drug discovery for Shigella. Main challenges in development of anti-shigella drugs are the lack of suitable animal models to evaluate compounds and the lack of information on PK/PD to anticipate in vivo efficacy and human dose. The first step in this project will be to test if the shigellosis B6 mouse model or other murine alternatives are suitable to evaluate antibiotics. Based on the localization of Shigella to the large intestine and the need to deliver antibiotics in GI tract, previous experience with PBPK-PD models to predict in vivo drug efficacy for anti-cryptosporidium drugs will be applied to predict in vivo efficacy of anti-Shigella compounds.

  • University of Melbourne - High throughput screening to identify selective proteasome inhibitors as new antimalarials with a novel mode of action (Oceanía)

    Start : May 2017 | Status : Active

    The scientists: Dr. Stanley Xie is a postdoctoral researcher at the University of Melbourne, working under the supervision of Dr. Leann Tilley. He has extensive experience studying the P. falciparum proteasome and the mechanisms of action of and resistance to artemisinins. He will focus his research on identification and characterization ofnew hits acting through the P. falciparum proteasome.

    The sponsor: University of Melbourne

    Foundation funding: The Foundation is providing £198.239 in support.

    GSK’s contribution: GSK will support the project with its enzymology and high throughput screening platforms and contribute with its past experience working on the P. falciparum Ubiquitin Proteasome System. Additionally, GSK will also provide access to Biosafety Level 3 facilities and to GSK´s collection of proprietary compounds.

    Project Description: Current antimalarial control is highly dependent on Artemisinin-based Combination Therapies (ACTs), which makes the emergence of artemisinin (ART) resistance extremely concerning. This situation highlights the need to identify new drugs targeting different mechanisms in the parasite. The proteasome is a validated target for malaria. Inhibitors of the proteasome show parasiticidal activity against both ART sensitive and resistant parasites, and are active both against sexual and asexual intraerythroctyic stages, as well as liver stages. Moreover, the Leann Tilley lab has demonstrated that inhibitors of the proteasome strongly synergize ART-mediated killing of P. falciparum, being also suitable for combination therapies. The objective of this Open Lab project is to undertake a screening campaign to identify P. falciparum-specific proteasome inhibitors, thereby avoiding any toxicity associated with inhibition of the human proteasome. An extensive compound characterization will be performed, determining the parasitological profile and the mechanism of action applying tools developed in parallel during the project.

  • University of Alabama at Birmingham - Self-poisoning of Mycobacterium tuberculosis by inhibiting siderophore secretion (America)

    Start : July 2016 | Status : Active

    The scientists: Dr. Avishek Mitra, Bjorn Sunde and Prof. Michael Niederweis will focus their research on the identification of small molecules that kill Mycobacterium tuberculosis by inhibiting siderophore efflux. Dr. Mitra is a postdoctoral researcher working on iron acquisition by M. tuberculosis in the laboratory of Prof. Niederweis in the Department of Microbiology at the University of Alabama at Birmingham. Bjorn Sunde is a research assistant with experience in performing high-throughput screening assays in Biosafety Level 3 laboratories.

    The sponsor:University of Alabama at Birmingham, Department of Microbiology

    Foundation funding: The Foundation is providing £263,119 in support.

    GSK’s contribution: GSK will provide access to biosafety level 3 and high-throughput screening facilities, microbiology and drug discovery expertise as well as full access to antimycobacterial compound sets.

    Project Description: Iron is an essential nutrient for M. tuberculosis which can acquire iron from heme and from its siderophores, mycobactin and carboxymycobactin. This project is based on the surprising finding that blocking siderophore secretion reduces the virulence of Mtb in mice by 10,000-fold. This is one of the strongest virulence defects observed for any Mtb mutant, probably due to the intracellular accumulation of siderophores. Externally added siderophores accumulate in the Mtb secretion mutant and are toxic at submicromolar concentrations. Importantly, this toxicity cannot be overcome by other iron sources such as heme in contrast to Mtb mutants deficient in siderophore biosynthesis. Since siderophore secretion spans both membranes, inhibitors might target this pathway from the outside of the cell and, thereby, might avoid the outer membrane permeability barrier of Mtb. We have developed a high-throughput screening assay that has identified inhibitors of Mtb whose activity depends on siderophores. These compounds are not detected in whole cell screens under standard conditions. Thus, siderophore secretion appears to be a valuable target for novel TB drugs that will be exploited in this project.

  • University of South Florida (USF), WRAIR and NIH - Antimalarial drug discovery targeting pre-erythrocytic stages of Plasmodium falciparum (America)

    Start : September 2019 | Status : Set up ongoing

    The scientists: Ana Lisa Valenciano

    The sponsor: University of South Florida (USF), WRAIR and NIH

    Foundation funding: The Foundation is providing £394,606 in support.

    GSK’s contribution: GSK to share access to all generated data and provide access/use of compounds identified from the screen for further evaluation beyond the scope of this proposal. The Tres Cantos unit will provide in kind assay consumables and resources equivalent to two full-time personnel who will assist with gametocyte production, mosquito rearing and infections, dissections, imaging, data analysis, and support.

    Project Description: This project offers a major advance in antimalarial drug discovery by targeting pre-erythrocytic stages to block malaria infection. We have developed an innovative P. falciparum in vitro liver assay to evaluate drug toxicity and inhibitory efficacy of critical early phase of malaria infection in human hepatocytes. Consequently, this project can efficiently evaluate drug inhibition of the complete liver stage of the malaria life cycle. Central to this new screening strategy is a G384 microplate culture system using primary human hepatocytes (PHHs)(1) with modified P. falciparum sporozoite isolation procedures (2, 3). To enhance identification of the best lead compounds we will use quantitative functional assays of sporozoite entry into and egress from human hepatocytes along with transmission-blocking assays for mosquito infections. In developing our assays, we identified key microenvironmental triggers of infectivity that downstream can be used to elucidate target specificity and mechanisms of action. Altogether we provide a comprehensive new screening strategy for antimalaria drugs to block infection.

  • Sanger Institute - A chemogenomic overexpression screen to identify malaria liver stage targets (Europe)

    Start : May 2019 | Status : Active

    The scientists: Cindy Smidt – 2nd openlab fellow pending on recruitment

    The sponsor: Sanger Institute

    Foundation funding: The Foundation is providing £181,975 in support.

    GSK’s contribution: At early stages of the project GSK will provide significant input in shortlisting compounds for target identification and provide panels of compounds, as well as collaboratively prioritising targets of interest to be included in the screening panel of PACs. GSK will as well perform chemical re-synthesis of compounds if required. Later they will provide chemo-informatics expertise for data analysis. Targets for validation will be jointly decided. At a late stage of the project, targets with potential for cellular or recombinant enzyme screening will be selected. If compounds have the appropriate characteristics (solubility, DMPK properties, etc) validation work in mouse models will be done at Tres Cantos.

    Project Description: There is a widely recognised need for antimalarial drugs that target liver stages (1) but the paucity of suitable liver stage culture systems for human Plasmodium species has so far limited their development. Screening systems are now improving, and cellular screens have identified compounds that selectively kill this parasite stage, with the expectation that such compounds would have prophylactic potential. However, current screening assays have limited throughput. Identifying targets would allow target-based screens in a high-throughput format and explore millions of compounds. Because of the culture systems target ID cannot be achieved through conventional resistance selection approaches used so successfully with blood stage targets (2). In addition, the inefficiency (in the case of P. falciparum) or impossibility (in the case of P. vivax) of experimental genetics has so far prevented rational, target-led approaches to develop liver-active compounds. The strategy we propose here will therefore be potentially paradigm shifting, since it enables systematic screens for targets of liver-specific compounds for the first time.

    Genome-scale chemical-genetic interaction screens have successfully identified small molecule targets in libraries of diploid yeast (3-4) that carry heterozygous loss-of-function mutations in individual genes, sensitising their carriers to inhibitors of the same target or pathway. For malaria parasites, which are haploid, we here present evidence that chemical-genetic interaction screening can be used to identify targets not only at the blood stage but also in liver stages. Working with P. berghei, a parasite species that is uniquely suited to study liver stage biology in vitro, we have generated tools and methods to increase expression of parasite genes in a controlled and selective manner by introducing extra copies of the part of the genome that encodes them. We have created a library of Plasmodium artificial chromosomes (PACs) that can be transfected efficiently in pools during blood stages and are faithfully inherited through mosquito and liver stages. Our preliminary data show that treating cultured liver stages reproducibly shifts the relative abundance of individual PACs in accordance with known modes of action and modes of resistance, associating targets with compounds in an unbiased manner.

    Using this approach, we have defined the parameters for successful chemogenomic screening in liver stages. We propose here to apply the system to screen 24 liver-active compounds against 625 high priority targets. We will then work with GSK to select and follow up on the most interesting new targets by more detailed validation, cellular/recombinant protein assay development and target-based screens, which will be used to discover new chemical series for future development.

  • University of Washington - High Throughput Screening for Inhibitors of Shigella Virulence Determinants (America)

    Start : June 2019 | Status : Active

    The scientists: Mayumi Holly

    The sponsor: University of Washington

    Foundation funding: The Foundation is providing £166,037 in support.

    GSK’s contribution: Technical assistance with the inhibitor screen including help with instruments and software. Access to GSK’s small molecule libraries. Extensive communication and advice regarding screen design, execution, troubleshooting, and compound identification.

    Project Description: The primary goal of this proposed project is to test the hypothesis that small molecule inhibitors of Shigella transcription factors can promote the rapid resolution of infection. Previously, data collected from an in vivo transposon library screen (TN-Seq) using a guinea pig model of shigellosis was performed to provide a global view of genes and pathways that are critical for Shigella to survive and compete within the host. Disrupting the expression of these crucial genes and pathways with small molecule inhibitors is expected to result in severe defects in Shigella’s ability to colonize the host and cause disease. The proposed project will use high throughput assays to screen compound libraries for inhibition of pathways deemed to be essential for Shigella to survive in the host. Identified hits will be validated and tested for their capacity to functionally alter the course of Shigella infection using established in vivo models. If successful, this strategy could act as a blueprint for developing new drugs that target essential survival pathways in microorganisms, leading to an entire new class of treatments against infectious diseases.

  • University of California - Hit-to-Lead Development of the Kalihinol Scaffold for Malaria Treatment (America)

    Start : June 2019 | Status : Active

    The scientists: Ramakrishna Kankanala - Milandip Karak

    The sponsor: University of California

    Foundation funding: The Foundation is providing £197,190 in support.

    GSK’s contribution:The in-kind contributions from GSK will involve the characterization of simplified kalihinol analogues for their efficacy, safety, pharmacodynamics, and pharmacokinetics properties, initially to ensure that this series of compounds is as promising as our initial data suggest. In the medium term, further evaluations of these types will guide a medicinal chemistry effort for hit-to-lead development.

    Project Description: The ultimate goal of this collaborative research program is to identify antimalarial clinical candidates among analogues of the kalihinol family of isocyanoterpenes (Figure 1), an understudied class of natural products with potent activity against Plasmodium falciparum, the causative agent of the deadliest form of human malaria. Preliminary data generated in our laboratories support the premise of this research that the kalihinols could be developed as novel antimalarial agents. Our data demonstrate that (i) kalihinol natural products have potent activity against blood stages of both drug-sensitive and drug-resistant P. falciparum strains with IC50 values in the low nanomolar range; (ii) the synthetic route to these compounds has been simplified producing analogues that retain potent antimalarial activity, and there is a chemical plan in place for further synthetic simplification; (iii) the compounds have good HepG2 inhibition data and no major in silico safety alerts, and; (iv) they may exert their antimalarial activity through a novel mode of action. Building upon this body of data, we propose to delve deeply into the structure-activity relationship of these compounds, characterize their in vitro and in vivo efficacy and safety, and unravel their mode of action.

  • University of Zaragoza- TB antivirulence therapeutics: small molecule inhibitors against M. tuberculosis replication and persistence pathways as novel alternatives to classic antibiotics. (Europe)

    Start : March 2019 | Status : Active

    The scientists: Stefan Prior - Irene Pérez

    The sponsor: University of Zaragoza

    Foundation funding: The Foundation is providing £174,268 in support.

    GSK’s contribution:The in-kind contributions from GSK will involve:

    • HTS using the GSK chemical library
    • Cytotoxicity, solubility, stability, …assays to define the value of identified compounds
    • Chemistry support for SAR and compound selection
    • Proteomics approaches
    • In vivo activity in a mouse model of TB virulence

    Project Description: Multidrug-resistant (MDR) and extensively drug-resistant (XDR) TB have alarmingly spread worldwide and make treatment difficult or even impossible. In addition, the one third of the human population latently infected with TB (LTBI) constitutes an enormous reservoir. Antivirulence therapies with small molecules that sabotage bacterial survival in the host may have advantages over traditional antibiotics because it targets factors required for pathogenesis, potentially reducing selection for resistance and limiting collateral damage to the resident microbiota (1, 2).

    Our project proposes a novel approach to disarm M. tuberculosis (Mtb), focused on searching antivirulence therapies against transcription factor PhoP as a paradigm regulon essential for Mtb virulence (3, 4). Recently, a small molecule inhibiting a transcription factor has been described to revert antibiotic resistance (5). We propose the construction of a reporter Mtb strain by placing strongly PhoP-regulated promoters (4) upstream GFP which will allow the screening of the complete GSK compound collection. Loss of GFP fluorescence upon treatment, indicative of selective virulence inhibition, can be easily monitored by high-throughput screening. Potential synergies between inhibitors, or between inhibitors and current anti-TB drugs will be assayed. We will confirm whether these compounds are active in macrophage and mouse models of TB and we also plan to assay the selected compounds against representative isolates of Mtb Complex lineages, which reflect the current genetic diversity of TB worldwide.

  • IBR-CONICET_UNR Instituto de Biología Molecular y Celular de Rosario - Trypanosoma cruzi bromodomains: druggable readers to look out! (America)

    Start : March 2019 | Status : Active

    The scientists: Luis Emilio Tavernelli

    The sponsor: IBR-CONICET_UNR Instituto de Biología Molecular y Celular de Rosario

    Foundation funding: The Foundation is providing £101,055 in support

    GSK’s contribution: GSK will give us access to a library of potential bromodomain inhibitors, as well to humans BRD proteins. On the other hand, GSK will let us introduce us in the field of high/medium throughput screening in which we lack expertise.

    Project Description: The discovery of new therapeutic options against Trypanosoma cruzi, the causative agent of Chagas disease stands as a fundamental need, since available drugs have significant toxic side effects and a variable efficacy against the life-threatening symptomatic chronic stage of the disease. Bromodomains are protein modules that bind to acetylated lysine residues. Their interaction with histone proteins suggests their role in interpreting the histone code. However, protein acetylation is not a phenomenon restricted to the nuclear proteins. Bromodomain-containing proteins are often found as components of larger protein complexes with roles in fundamental cellular process including transcription, cell cycle regulation, among others. In 2010 two BET bromodomains ligands were described demonstrating that small molecules could inhibit the bromodomain-acetyl-lysine interaction. These molecules display strong phenotypic effects in a number of cell lines and affect a range of cancers in vivo. Recent reports showed that bromodomain inhibitors affect T. cruzi viability and deregulate the expression of stage-specific proteins in T. brucei. The overall objective of this project is to search for bromodomain inhibitors in T. cruzi, by assaying essentials bromodomains previously established in a collaborative GSK-sponsored research project between Esteban Serra’s and Roberto Docampo’s labs. From this project three bromodomains from T. cruzi were selected as putative targets against Chagas disease.

  • University of Cambridge - High throughput small molecule screen for drugs that alter the shape of Campylobacter jejuni (Europe)

    Start : June 2020 | Status : Active

    The scientists: TBD

    The sponsor: University of Cambridge

    Foundation funding: The Foundation is providing £143,040 in support

    GSK’s contribution: GSK will contribute with high throughput screening expertise to miniaturize the assay. GSK will provide compounds for screening and access to Shigella animal models as well as drug discovery expertise to assess the potential of this approach to deliver a drug for patients.

    Project Description: The world faces a major infectious disease challenge that is being made worse by antimicrobial resistance. We need new therapeutic modalities that overcome resistance and that do not affect the natural gastrointestinal flora, which is proven to be essential for gastrointestinal health. We contend that cell shape may be a targetable Achilles heel for enteric bacterial pathogens and has not yet been fully exploited for drug discovery applications. There is evidence that cell shape can affect the virulence of pathogens (e.g. Campylobacter spp. and Salmonella spp.). Through this Open Lab project, this characteristic will be exploited for high-throughput screens against Shigella spp. and other enteric bacteria.

  • Research Agency of Aragon (ARAID) & University of Zaragoza (UNIZAR)- Predicting optimal dosing schedules and clinical outcomes of beta‐lactams for TB therapy using PKPD and mechanistic models Carbapenem vs. cephem: the beta‐lactam paradigm (Europe)

    Start : April 2018 | Status : Active

    The scientists: Santiago Ramón - María Pilar Arenaz

    The sponsor: Research Agency of Aragon (ARAID) & University of Zaragoza (UNIZAR)

    Foundation funding: The Foundation is providing £141,500 in support

    GSK’s contribution: GSK’s in kind contributions would be critical for the following: (i) Access to time-lapse microscopy and micro-pumping system to mimic PK profiles; (ii) imaging and analytical modeling software and skills; (iii) access to clinical data for modeling. In addition, based on previous experience (RIFACEPH project), the excellent scientific and personal support provided by GSK scientists would greatly facilitate the successful outcome of this proposal.

    Project Description: This proposal aligns and complements with current clinical trials now being explored by GSK DDW clinical partners. It also comes with additional funding that the applicant, Dr. Ramón-García, recently secured from the European Community for a 2-year project to be performed at GSK DDW.

    Carbapenems and cephems are beta-lactam (BLMs) antibiotics with different anti-tuberculosis (TB) killing properties and phenotypic responses that might affect therapy design for optimal clinical outcomes (Figure 1). Understanding the pharmacokinetic (PK) and pharmacodynamic (PD) parameters of BLMs alone and in combination with synergistic partners is critical if they are to be used for TB therapy (Figure 2). Similarly, the molecular determinants underlying synergistic interactions of BLMs with synergistic partner drugs are currently unknown. Elucidating the synergistic mode of action of such combinations will allow the design of novel strategies for TB therapy and help counteract the emergence of future resistance.

    To answer these questions, time-lapse microscopy, in vitro microbiology assays and transcriptomic studies will be leveraged to provide high quality molecular and pre-clinical data that, through mathematical PKPD modeling based on completed and ongoing GSK DDW BLM-containing TB clinical trials, will inform the design of future human combination trials with BLM components.Campylobacter spp. and Salmonella spp.). Through this Open Lab project, this characteristic will be exploited for high-throughput screens against Shigella spp. and other enteric bacteria.

  • EMBL- Unravelling new combinatorial therapies against Shigellosis

    Start : July 2018 | Status : Active (Europe)

    The scientists: 2 FTE at EMBL

    The sponsor: EMBL

    Foundation funding: The Foundation is providing £131,383 in support

    GSK’s contribution: GSK will provide expertise with high throughput screening set ups and compound screening, as well as with data analysis. GSK will provide compound libraries and drug discovery expertise to assist in the compound selection. Materials for the experimental part performed at GSK will be provided in kind. GSK pharmacologist experts will support this project to unravel the PK/PD of synergistic combinations.

    Project Description: Combinatorial treatments provide an untapped, cost-effective source for new antibacterial treatments at a time where new therapies are urgently needed. Here we propose to establish a high-content microscopy platform for systematically screening drug combinations against intracellular Shigella. Shigellosis is one of the leading causes of diarrhea worldwide, with infections being more frequent and deadly in the developing world. The microscopy platform set up will not only facilitate high-throughput screening at the intracellular context of infection, where this pathogen has to be targeted, but will also provide insights into the mechanism-of-action of single drug(s) and the combinatorial treatment by monitoring the stage of infection and the host process(es) they affect. Using this platform, we will evaluate the impact of ~5,000 drug combinations during the course of infection in epithelial cells and macrophages. Strong synergies will be further evaluated in detailed surface response measurements (inhibition and killing curves – intracellularly and extracellularly), resistant and persistent assays. Last, prominent candidates will be moved to animal models and PK/PD measurements.

  • University of Michigan - Targeting Virulence Regulators as a Novel Approach to Antibiotics for Shigellosis (America)

    Start : Nov 2018 | Status : Active

    The scientists: Marija Miljkovic

    The sponsor: University of Michigan

    Foundation funding: The Foundation is providing £93,585 in support

    GSK’s contribution: GSK will provide compounds for screening, consumables and expertise to perform the HTS and to select and prioritize the most promising hits. Biology and pharmacology support will be provided as well.

    Project Description: Diarrheal diseases, such as shigellosis, are the second leading cause of death in children under five years old. Many strains of Shigella spp. are drug or multi-drug resistant. Genetic knock-out studies of the Shigella virulence pathway controlled by the AraC-family transcription factor VirF (required for infection, cell-to-cell spread and escape from macrophages) show that inactivation of VirF or other virulence factors eliminates, or significantly reduces, pathogenicity. Importantly, expression of virulence factors is not required for Shigella viability; therefore, targeting virulence factors is expected to lower the risk for resistance development in Shigella while not affecting normal, avirulent colonic microbiota. We have identified 5 hits from an HTS of ~150,000 small molecules that inhibit VirF expression of a reporter gene and reduce the invasion efficiency of Shigella in in vitro models of infection. One of these hits blocks VirF binding to DNA. Our goal in this proposal is to identify novel and potent chemical matter that block Shigella virulence to conduct a ‘hit-to-lead” campaign. We will screen compounds from GSK’s 1.7M compound library, perform confirmation and secondary assays probing mechanism of action, PK/Tox and in vitro efficacy. Compounds that inhibit VirF•DNA binding will be co-crystalized with the VirF DNA binding domain to enable a structure-based hit-to-lead campaign

  • University of Georgia + Bioaster- Chagas AABLO (Chagas AcylAminoBenzothiazol Lead Optimization) (Europe)

    Start : January 2018 | Status : Active

    The scientists: Charlotte Fleau

    The sponsor: University of Georgia + Bioaster

    Foundation funding: The Foundation is providing £159,226 in support

    GSK’s contribution: Chemistry labs for synthesis, purification, structure analysis. Full Profiling of Development pre-Candidate (ADMET2 and early toxicology).

    Project Description: T. cruzi is a protozoan parasite that causes Chagas disease, the highest impact infectious disease in Latin America. Although the host immune response is highly effective at controlling T. cruzi, the infection persists in most infected hosts. Previous work between our groups at The University of Georgia (UGA), Sanofi and BIOASTER has identified several Acyl-AminoBenzothiazol (AAB) hits with potent in vitro and in vivo toxicity for T. cruzi. These related hits came from an initial in vitro screen of a ~300,000 small molecule library by the Broad Institute (Pubchem AID: 1885); 171 of the ~3500 in hits with in vitro activity were selected for in vivo screening based upon druglikeness, potential for oral delivery and ease of synthesis and novelty. In a rapid in vivo efficacy assay, 5 of the 171 compounds showed strong activity – 3 of those 5 were in this AAB group. Subsequent in vitro SAR of 240 analogues revealed 3 AAB compounds with IC50 of < 80 nM and identified the steps needed to optimize this compound class. Herein we describe the med chem plan for this optimization as well as for identification of the mechanism of action of these compounds. Paired with our unparalleled combination of in vitro and in vivo screening assays, and the prior evidence of in vivo efficacy of this compound class, we have an excellent opportunity to identify one or more compounds capable of providing parasitological cure.

  • Oxford University - Structural biology and assays enabling β-lactams that target Mycobacteria tuberculosis (Europe)

    Start : July 2017 | Status : Active

    The scientists: Jurgen Brem – Mariska de Munnik

    The sponsor: Oxford University

    Foundation funding: The Foundation is providing £177,625 in support

    GSK’s contribution: - Determination of anti Mtb activity in vitro and in vivo. Oxford University does not have the capacity required for this work, therefore a collaboration with GSK TC is essential for the project.

    - Supply of compounds for testing in assays and structural evaluation (Note initial work will focus on compounds already available, with focused medicinal chemistry being the subject of a new funding application.)

    - Expertise in mechanistic chemistry (including modeling) to be used in inhibitor design possibly coupled to modeling

    - Assistance in project management including via frequent (Skype / phone) meetings

    - Expertise in identifying routes to pre-clinical and clinical candidates

    - A desire to work together to secure future large-scale funding to develop -lactam / analogous compounds to be used for Mtb treatment

    - The ability to work collaboratively with Oxford to rapidly follow up breakthrough results on new types of inhibitor.

    Project Description: β-Lactams, including penicillins, cephalosporins and carbapenems, remain the most important antibiotics in use for treatment of Gram- and Gram+ bacteria, but their use is compromised by growing resistance, most importantly due to widespread β-lactamase dissemination. Mycobacteria tuberculosis (Mtb) has a higher mortality rate than any other infectious disease; however, β-lactams have traditionally not been effective in Mtb treatment. The paradigm that β-lactams are not useful for treatment of Mtb (including XDR Mtb) is based on the poor cell permeability/stability/oral use of ‘classical’ β-lactams (which poorly penetrate the cell-membrane) and the presence of a genetically encoded β-lactamase (BlaC) in Mtb. This paradigm is now being questioned [1-3], because: (i) Recent clinical trials shows that meropenem combined with amoxicillin–clavulanic acid has potential for treating Mtb; (ii) Carbapenems not only inhibit Mtb D,D-transpeptidases, but can also Mtb inhibit L,D-transpeptidases ; (iii) Clinically used cephalosporins in combination with clavulanic acid manifest synergistic effects in Mtb treatment; (iv) novel cephalosporins with C-2 carboxylate isosters have shown selective activity against non-replicating Mtb [3]. Thus, the timing is right for focused efforts to develop tailored β-lactams for Mtb treatment together BlaC inhibitors, the latter being the initial focus of our proposed work.

    Such work will be enabled by contemporary availability of: (i) New types of transpeptidase / β-lactamase inhibitors, including new acylating agents, such as those based on avibactam and lactivicins [9], and ‘transition state analogues’ e.g. cyclic boronates that display remarkable potency against β-lactamases [5]; such compounds have potential as transpeptidase inhibitors with very different PK/PD properties compared to classical β-lactams; (ii) Extensive new structural and mechanistic information on β-lactam mode of action and resistance mechanisms has emerged since the classical β-lactams were developed; (iv) New synthetic methodologies enable access to complex densely functionalised rings systems (e.g. functionalized oxapenems) previously unviable due to ‘cost of goods’ issues; (v) Knowledge of (Mtb infected) human cell biology will enable more rational targeting of β-lactams to Mtb in human cells. The focus of this OpenLab project will be structural, screening, and mechanistic work (including involving new inhibitors types) that will enable future medicinal chemistry efforts to enable clinically useful BlaC resistant PBP inhibitors for oral Mtb treatment.

  • Oxford University Clinical Research Unit- Hit discovery for new antimicrobials against Shigella spp. (Europe)

    Start : April 2017 | Status : Active

    The scientists: Andrew Lim – Phat Voong Vinh

    The sponsor: Oxford University Clinical Research Unit

    Foundation funding: The Foundation is providing £174,038 in support

    GSK’s contribution: GSK will provide facilities for HTS and compound collections to be screened. In addition, GSK will provide resources in kind for DMPK and safety profiling of the interesting hits identified.

    Project Description: Our ultimate aim is to develop new drugs for the treatment of infections caused by Shigella spp. (a major cause of diarrhea in low-income countries) that work through novel mechanisms of action. Within this open-lab application we aim to carry out the following:

    • Phenotypic screening against Shigella sonnei and Shigella flexneri 2a using chemically diverse compound libraries under a variety of conditions aiming, where possible, to mimic physiological conditions.
    • Screening compound libraries against AMR isolates in the presence of antimicrobials to which they are resistant, aiming to identify compounds that restore antimicrobial activity
    • Compound hits will be validated through assay against panels of clinical isolates, including newly emergent MDR strains.
    • Validated hits will be profiled in various in vitro DMPK assays, such as solubility and metabolic stability. Preliminary safety assessment in silico and in vitro will be additionally performed, as well as hit expansion.