Extending infection prevention and control nursing (IPCN) provision to weekends at one National Health Service hospital in the United Kingdom: A feasibility and acceptability study.

Background: Hospital Infection Prevention and Control Teams (IPCTs) provide clinical cover during weekdays with on call support at weekends. We report the results of a 6-month pilot of extending infection prevention and control nursing (IPCN) clinical cover to weekends at one National Health Service trust in the United Kingdom. Methods: We examined daily episodes of infection prevention and control (IPC) clinical advice given before and during the pilot of extended IPCN to weekends. Stakeholders rated the value, impact, and their awareness of the new extended IPCN cover. Results: Episodes of clinical advice given were more evenly distributed across the weeks during the pilot. Advantages for infection management, patient flow, and clinical workload were seen. Conclusions: IPCN clinical cover at weekends is feasible and valued by stakeholders.

Optimization of an Imidazo[1,2-a]pyridine Series to Afford Highly Selective Type I1/2 Dual Mer/Axl Kinase Inhibitors with In Vivo Efficacy.

Inhibition of Mer and Axl kinases has been implicated as a potential way to improve the efficacy of current immuno-oncology therapeutics by restoring the innate immune response in the tumor microenvironment. Highly selective dual Mer/Axl kinase inhibitors are required to validate this hypothesis. Starting from hits from a DNA-encoded library screen, we optimized an imidazo[1,2-a]pyridine series using structure-based compound design to improve potency and reduce lipophilicity, resulting in a highly selective in vivo probe compound 32. We demonstrated dose-dependent in vivo efficacy and target engagement in Mer- and Axl-dependent efficacy models using two structurally differentiated and selective dual Mer/Axl inhibitors. Additionally, in vivo efficacy was observed in a preclinical MC38 immuno-oncology model in combination with anti-PD1 antibodies and ionizing radiation.

A multi-batch design to deliver robust estimates of efficacy and reduce animal use - a syngeneic tumour case study.

Phenotypic plasticity, the ability of a living organism to respond to the environment, can lead to conclusions from experiments that are idiosyncratic to a particular environment. The level of environmental responsiveness can result in difficulties in reproducing studies from the same institute with the same standardised environment. Here we present a multi-batch approach to in-vivo studies to improve replicability of the results for a defined environment. These multi-batch experiments consist of small independent mini-experiments where the data are combined in an integrated data analysis to appropriately assess the treatment effect after accounting for the structure in the data. We demonstrate the method on two case studies with syngeneic tumour models which are challenging due to high variability both within and between studies. Through simulations and discussions, we explore several data analysis options and the optimum design that balances practical constraints of working with animals versus sensitivity and replicability. Through the increased confidence from the multi-batch design, we reduce the need to replicate the experiment, which can reduce the total number of animals used.

Longitudinal immune characterization of syngeneic tumor models to enable model selection for immune oncology drug discovery.

BACKGROUND: The ability to modulate immune-inhibitory pathways using checkpoint blockade antibodies such as αPD-1, αPD-L1, and αCTLA-4 represents a significant breakthrough in cancer therapy in recent years. This has driven interest in identifying small-molecule-immunotherapy combinations to increase the proportion of responses. Murine syngeneic models, which have a functional immune system, represent an essential tool for pre-clinical evaluation of new immunotherapies. However, immune response varies widely between models and the translational relevance of each model is not fully understood, making selection of an appropriate pre-clinical model for drug target validation challenging. METHODS: Using flow cytometry, O-link protein analysis, RT-PCR, and RNAseq we have characterized kinetic changes in immune-cell populations over the course of tumor development in commonly used syngeneic models. RESULTS: This longitudinal profiling of syngeneic models enables pharmacodynamic time point selection within each model, dependent on the immune population of interest. Additionally, we have characterized the changes in immune populations in each of these models after treatment with the combination of α-PD-L1 and α-CTLA-4 antibodies, enabling benchmarking to known immune modulating treatments within each model. CONCLUSIONS: Taken together, this dataset will provide a framework for characterization and enable the selection of the optimal models for immunotherapy combinations and generate potential biomarkers for clinical evaluation in identifying responders and non-responders to immunotherapy combinations.

Discovery of a Thiadiazole-Pyridazine-Based Allosteric Glutaminase 1 Inhibitor Series That Demonstrates Oral Bioavailability and Activity in Tumor Xenograft Models.

Tumors have evolved a variety of methods to reprogram conventional metabolic pathways to favor their own nutritional needs, including glutaminolysis, the first step of which is the hydrolysis of glutamine to glutamate by the amidohydrolase glutaminase 1 (GLS1). A GLS1 inhibitor could potentially target certain cancers by blocking the tumor cell's ability to produce glutamine-derived nutrients. Starting from the known GLS1 inhibitor bis-2-(5-phenylacetamido-1,2,4-thiadiazol-2-yl)ethyl sulfide, we describe the medicinal chemistry evolution of a series from lipophilic inhibitors with suboptimal physicochemical and pharmacokinetic properties to cell potent examples with reduced molecular weight and lipophilicity, leading to compounds with greatly improved oral exposure that demonstrate in vivo target engagement accompanied by activity in relevant disease models.

PI3Kα/δ inhibition promotes anti-tumor immunity through direct enhancement of effector CD8+ T-cell activity.

PI3K inhibitors with differential selectivity to distinct PI3K isoforms have been tested extensively in clinical trials, largely to target tumor epithelial cells. PI3K signaling also regulates the immune system and inhibition of PI3Kδ modulate the tumor immune microenvironment of pre-clinical mouse tumor models by relieving T-regs-mediated immunosuppression. PI3K inhibitors as a class and PI3Kδ specifically are associated with immune-related side effects. However, the impact of mixed PI3K inhibitors in tumor immunology is under-explored. Here we examine the differential effects of AZD8835, a dual PI3Kα/δ inhibitor, specifically on the tumor immune microenvironment using syngeneic models. Continuous suppression of PI3Kα/δ was not required for anti-tumor activity, as tumor growth inhibition was potentiated by an intermittent dosing/schedule in vivo. Moreover, PI3Kα/δ inhibition delivered strong single agent anti-tumor activity, which was associated with dynamic suppression of T-regs, improved CD8+ T-cell activation and memory in mouse syngeneic tumor models. Strikingly, AZD8835 promoted robust CD8+ T-cell activation dissociated from its effect on T-regs. This was associated with enhancing effector cell viability/function. Together these data reveal novel mechanisms by which PI3Kα/δ inhibitors interact with the immune system and validate the clinical compound AZD8835 as a novel immunoncology drug, independent of effects on tumor cells. These data support further clinical investigation of PI3K pathway inhibitors as immuno-oncology agents.

Pre-clinical pharmacology of AZD3965, a selective inhibitor of MCT1: DLBCL, NHL and Burkitt's lymphoma anti-tumor activity.

Tumors frequently display a glycolytic phenotype with increased flux through glycolysis and concomitant synthesis of lactate. To maintain glycolytic flux and prevent intracellular acidification, tumors efflux lactate via lactate transporters (MCT1-4). Inhibitors of lactate transport have the potential to inhibit glycolysis and tumor growth. We developed a small molecule inhibitor of MCT1 (AZD3965) and assessed its activity across a panel of cell lines. We explored its antitumor activity as monotherapy and in combination with doxorubicin or rituximab. AZD3965 is a potent inhibitor of MCT1 with activity against MCT2 but selectivity over MCT3 and MCT4. In vitro, AZD3965 inhibited the growth of a range of cell lines especially haematological cells. Inhibition of MCT1 by AZD3965 inhibited lactate efflux and resulted in accumulation of glycolytic intermediates. In vivo, AZD3965 caused lactate accumulation in the Raji Burkitt's lymphoma model and significant tumor growth inhibition. Moreover, AZD3965 can be combined with doxorubicin or rituximab, components of the R-CHOP standard-of-care in DLBCL and Burkitt's lymphoma. Finally, combining lactate transport inhibition by AZD3965 with GLS1 inhibition in vitro, enhanced cell growth inhibition and cell death compared to monotherapy treatment. The ability to combine AZD3965 with novel, and standard-of-care inhibitors offers novel combination opportunities in haematological cancers.

Identification of Pharmacodynamic Transcript Biomarkers in Response to FGFR Inhibition by AZD4547.

The challenge of developing effective pharmacodynamic biomarkers for preclinical and clinical testing of FGFR signaling inhibition is significant. Assays that rely on the measurement of phospho-protein epitopes can be limited by the availability of effective antibody detection reagents. Transcript profiling enables accurate quantification of many biomarkers and provides a broader representation of pathway modulation. To identify dynamic transcript biomarkers of FGFR signaling inhibition by AZD4547, a potent inhibitor of FGF receptors 1, 2, and 3, a gene expression profiling study was performed in FGFR2-amplified, drug-sensitive tumor cell lines. Consistent with known signaling pathways activated by FGFR, we identified transcript biomarkers downstream of the RAS-MAPK and PI3K/AKT pathways. Using different tumor cell lines in vitro and xenografts in vivo, we confirmed that some of these transcript biomarkers (DUSP6, ETV5, YPEL2) were modulated downstream of oncogenic FGFR1, 2, 3, whereas others showed selective modulation only by FGFR2 signaling (EGR1). These transcripts showed consistent time-dependent modulation, corresponding to the plasma exposure of AZD4547 and inhibition of phosphorylation of the downstream signaling molecules FRS2 or ERK. Combination of FGFR and AKT inhibition in an FGFR2-mutated endometrial cancer xenograft model enhanced modulation of transcript biomarkers from the PI3K/AKT pathway and tumor growth inhibition. These biomarkers were detected on the clinically validated nanoString platform. Taken together, these data identified novel dynamic transcript biomarkers of FGFR inhibition that were validated in a number of in vivo models, and which are more robustly modulated by FGFR inhibition than some conventional downstream signaling protein biomarkers. Mol Cancer Ther; 15(11); 2802-13. ©2016 AACR.

The AMFm and Medicine Diversion: Good intent enabling corrupt practices.

Increased donated and subsidised medicines for malaria are saving countless lives in Africa, but there is probably increasing theft and diversion of those medicines. The impact of medicine diversion is unknown but potentially dangerous and may bolster criminal networks and increase medicine stock outs (1,2). This study demonstrates that diversion is widespread; diverted subsidised medicines were found in 11 of 14 cities investigated, and in four of those, over half the pharmacies researchers visited had diverted subsidised malaria products.

Anti-infective medicine quality: analysis of basic product quality by approval status and country of manufacture.

BACKGROUND: Some medicines for sale in developing countries are approved by a stringent regulatory authority (SRA) or the World Health Organization (WHO) prequalification program; many of these are global brands. This study ascertains whether medicines approved by SRAs or the WHO perform better in simple quality tests than those that have not been approved by either. METHODS: Over the past 4 years, 2652 essential drugs (products to treat malaria, tuberculosis, and bacterial infections) were procured by covert shoppers from eleven African cities and eight cities in a variety of mid-income nations. All samples were assessed using the Global Pharma Health Fund eV Minilab® protocol to identify whether they were substandard, degraded, or counterfeit. RESULTS: The failure rate among SRA-approved products was 1.01%, among WHO-approved products was 6.80%, and 13.01% among products that were not approved by either. African cities had a greater proportion of SRA- or WHO-approved products (31.50%) than Indian cities (26.57%), but they also experienced a higher failure rate (14.21%) than Indian cities (7.83%). The remainder of cities tested had both the highest proportion of approved products at 34.46% and the lowest failure rate at 2.70%. Products made in Africa had the highest failure rate at 25.77%, followed by Chinese products at 15.74%, Indian products at 3.70%, and European/US products, which failed least often, at 1.70%. Most worrying is that 17.65% of Chinese products approved by the WHO failed. CONCLUSION: The results strongly indicate that approval by either an SRA or the WHO is correlated with higher medicine quality at a statistically significant level. The comparatively high failure rates among WHO-approved products suggest there may be some weakness in post-marketing surveillance of these products, especially of Chinese-made WHO-approved products. The discrepancy between the failure rate of WHO-approved products from India (2.39%) and China (17.65%) is cause for concern. It is possible that more of the failures originating in China are counterfeit products, but this cannot be ascertained without greater help from the manufacturers themselves.

Subsidizing artemisinin-based combination therapies: a preliminary investigation of the Affordable Medicines Facility - malaria.

BACKGROUND: The Affordable Medicines Facility - malaria (AMFm) is a subsidy mechanism to lower the price of, and hence increase access to, the best antimalarial medicines, artemisinin-based combination therapies (ACTs). While the AMFm stipulates that only quality-approved products are eligible for subsidy, it is not known whether those products, when actually supplied, are of good quality and comport with established pharmacopeial guidance on formulation and content of active ingredients. This study aimed to assess price and quality of AMFm ACTs, to compare AMFm ACTs with non-AMFm ACTs and artemisinin monotherapies, and to assess whether AMFm ACTs have been pilfered and diverted to a nearby country. METHODS: In all, 140 artemisinin-based antimalarial drugs were acquired from 37 pharmacies in Lagos, Nigeria, and Accra, Ghana. An additional ten samples of AMFm ACTs were collected from Lomé, Togo (not participating in the AMFm). Samples were analyzed using high-performance liquid chromatography. RESULTS: The AMFm ACTs were lower in price than many of the other drugs collected, but by less than anticipated or stipulated by the participating governments of Nigeria and Ghana. The quality of the AMFm ACTs was not universally good: overall, 7.7% had too little active pharmaceutical ingredient (API) and none had too much - these results are not likely to be as a result of random chance. AMFm ACTs were also found to have been diverted, both to pharmacies in Lagos not participating in the AMFm and to a foreign city (Lomé) where the AMFm is not operational. CONCLUSION: The AMFm is at best imperfectly displacing undesirable monotherapies, some portion of which are replaced by ACTs lacking sufficient API, which are often sold at prices exceeding government authorization. ACTs sold at a lower price with low-dose API, potentially extrapolated to approximately 100 million treatments ordered under the AMFm for Nigeria and Ghana, represent a possible concern to public health and the promotion of drug resistance.

AZD4547: an orally bioavailable, potent, and selective inhibitor of the fibroblast growth factor receptor tyrosine kinase family.

The fibroblast growth factor (FGF) signaling axis is increasingly implicated in tumorigenesis and chemoresistance. Several small-molecule FGF receptor (FGFR) kinase inhibitors are currently in clinical development; however, the predominant activity of the most advanced of these agents is against the kinase insert domain receptor (KDR), which compromises the FGFR selectivity. Here, we report the pharmacologic profile of AZD4547, a novel and selective inhibitor of the FGFR1, 2, and 3 tyrosine kinases. AZD4547 inhibited recombinant FGFR kinase activity in vitro and suppressed FGFR signaling and growth in tumor cell lines with deregulated FGFR expression. In a representative FGFR-driven human tumor xenograft model, oral administration of AZD4547 was well tolerated and resulted in potent dose-dependent antitumor activity, consistent with plasma exposure and pharmacodynamic modulation of tumor FGFR. Importantly, at efficacious doses, no evidence of anti-KDR-related effects were observed, confirming the in vivo FGFR selectivity of AZD4547. Taken together, our findings show that AZD4547 is a novel selective small-molecule inhibitor of FGFR with potent antitumor activity against FGFR-deregulated tumors in preclinical models. AZD4547 is under clinical investigation for the treatment of FGFR-dependent tumors.

Pilot study of essential drug quality in two major cities in India.

BACKGROUND: India is an increasingly influential player in the global pharmaceutical market. Key parts of the drug regulatory system are controlled by the states, each of which applies its own standards for enforcement, not always consistent with others. A pilot study was conducted in two major cities in India, Delhi and Chennai, to explore the question/hypothesis/extent of substandard and counterfeit drugs available in the market and to discuss how the Indian state and federal governments could improve drug regulation and more importantly regulatory enforcement to combat these drugs. METHODOLOGY/PRINCIPAL FINDINGS: Random samples of antimalarial, antibiotic, and antimycobacterial drugs were collected from pharmacies in urban and peri-urban areas of Delhi and Chennai, India. Semi-quantitative thin-layer chromatography and disintegration testing were used to measure the concentration of active ingredients against internationally acceptable standards. 12% of all samples tested from Delhi failed either one or both tests, and were substandard. 5% of all samples tested from Chennai failed either one or both tests, and were substandard. Spatial heterogeneity between pharmacies was observed, with some having more or less substandard drugs (30% and 0% respectively), as was product heterogeneity, with some drugs being more or less frequently substandard (12% and 7% respectively). CONCLUSIONS/SIGNIFICANCE: In a study using basic field-deployable techniques of lesser sensitivity rather than the most advanced laboratory-based techniques, the prevalence of substandard drugs in Delhi and Chennai is confirmed to be roughly in accordance with the Indian government's current estimates. However, important spatial and product heterogeneity exists, which suggests that India's substandard drug problem is not ubiquitous, but driven by a subset of manufacturers and pharmacies which thrive in an inadequately regulated environment. It is likely that the drug regulatory system in India needs to be improved for domestic consumption, and because India is an increasingly important exporter of drugs for both developed and developing countries. Some poor countries with high burdens of disease have weak drug regulatory systems and import many HIV/AIDS, tuberculosis and malaria drugs from India.

Docking interactions in the c-Jun N-terminal kinase pathway.

The c-Jun N-terminal kinase (JNK) signaling pathway is a major mediator of stress responses in cells. Similar to other mitogen-activated protein kinases (MAPKs), JNK activity is controlled by a cascade of protein kinases and by protein phosphatases, including dual-specificity MAPK phosphatases. Components of the JNK pathway associate with scaffold proteins that modulate their activities and cellular localization. The JNK-interacting protein-1 (JIP-1) scaffold protein specifically binds JNK, MAPK kinase 7 (MKK7), and members of the mixed lineage kinase (MLK) family, and regulates JNK activation in neurons. In this study we demonstrate that distinct regions within the N termini of MKK7 and the MLK family member dual leucine zipper kinase (DLK) mediate their binding to JIP-1. We have also identified amino acids in JNK required for: (a) binding to JIP-1 and for JIP-1-mediated JNK activation, (b) docking to MAPK kinase 4 (MKK4) and efficient phosphorylation by MKK4, and (c) docking to its substrate c-Jun and efficient c-Jun phosphorylation. None of the amino acids identified were essential for JNK docking to MKK7 or the dual-specificity phosphatase MAPK phosphatase 7 (MKP7). These findings uncover molecular determinants of JIP-1 scaffold complex assembly and demonstrate that there are overlapping, but also distinct, binding determinants within JNK that mediate interactions with scaffold proteins, activators, phosphatases, and substrates.