General practice pharmacist-led antipsychotic physical health monitoring: a prospective intervention scoping study

BACKGROUND

People with severe mental health illness die prematurely, often due to preventable cardiometabolic disease, which can be exacerbated by antipsychotic medicines that are effective for treating mental illness. Literature demonstrates that physical health monitoring, as recommended in guidelines, for people receiving antipsychotics is substandard. Therefore, we aimed to scope the potential of a general practice clinical pharmacist (GPCP)-led multidisciplinary intervention optimising adherence to cardiometabolic monitoring guidelines and delivering polypharmacy reviews.

METHOD

Prospective intervention scoping study in three urban general practices; one usual care, two intervention. Patients 18-65 years old prescribed oral antipsychotics were identified from records, and invited for cardiometabolic monitoring and GPCP medication review, from January to December 2022. Interventions and onward referrals were recorded and collated. Anonymised pre- and post-review data were analysed, and actions were graded for clinical importance.

RESULTS

In total 1.5% (210/14,159) of patients aged 18-65 years met inclusion criteria; usual care practice (n = 58); and intervention practices (n = 152). From baseline, the usual care practice achieved an absolute 7% increase in the cardiometabolic monitoring care bundle (glucose/glycosylated haemoglobin, lipids, blood pressure plus body mass index) versus 19-58% in the intervention practices. Two-thirds (92/152) of patients participated in medication reviews, requiring pharmacological and/or non-pharmacological clinical actions. The majority of actions were graded as moderate importance. Seven percentage of patients were identified as new pre-diabetic/diabetic and 6% were at high risk of cardiovascular disease requiring statin initiation.

CONCLUSION

A pharmacist-led multidisciplinary general practice-based approach may be effective at optimising cardiometabolic monitoring; identifying and treating diabetic and cardiovascular risk factors.

Greening procurement: Exploring evolving practices in an Irish university

Including green criteria in the public procurement of goods and services requires increased expertise, new methodologies, more significant monitoring efforts and more support towards innovation. These added complexities influence procurement professionals and their everyday practices. This article explores the under-researched issue of practitioner-led beliefs, attitudes, and their accounts of Green Public Procurement (GPP). We delve into a qualitative case study of University College Cork (UCC) in Ireland to explore the journey of procurement professionals in introducing GPP across the various sectors and departments of the university. We draw from interviews, a horizon scanning workshop, and secondary materials to capture and build on the expertise of a broad range of staff in UCC with experience in this area. We use this collective viewpoint to make sense of GPP and to position such views relative to ongoing policy priorities, looking at past, present, and future outlooks. The research shows that efforts have been made to introduce green criteria in new tenders. These gradually became wider opportunities to develop competencies, skills, and stimuli to implement more impactful strategies. The research also shows underdeveloped practices around supporting innovation, monitoring, and post-award evaluation. Overall, the paper offers a unique perspective based on the day-to-day practice of public procurement practitioners. While the case study is geographically bound and therefore presents difficulties in replicating findings, it provides a new lens for researching GPP adoption through interaction with practitioners.

A phase I/II study of the CXCR2 inhibitor, AZD5069, in combination with durvalumab, in patients (pts) with advanced hepatocellular carcinoma (HCC)

TPS631

Background: HCC is increasing rapidly in incidence worldwide driven by a rise in chronic liver disease including non-alcoholic steato-hepatitis (NASH). Most pts are not suitable for curative or loco-regional treatments and may be candidates for systemic therapies. Immune checkpoint inhibitors combined with VEGF inhibition is a standard of care in HCC. However, a meta-analysis of 3 phase III randomised trials of PD-1 or PDL-1 inhibitors (n > 1,600 pts) with HCC suggests that pts with NASH-related HCC treated with PD-1/PDL-1 inhibitors had reduced overall survival compared with other aetiologies. Neutrophils expressing the chemokine receptor CXCR2, crucial to neutrophil recruitment in acute-injury, are highly represented in NASH-HCC. In NASH-HCC murine models, lacking response to immune-checkpoint inhibitors, AZD5069 (CXCR2 inhibitor) in combination with anti-PDL-1 suppressed tumor burden and extended survival, accompanied by an increase in tumor-associated neutrophils which switched from a pro-tumor to anti-tumor progenitor-like neutrophil phenotype. We propose that inhibition of CXCR2 may potentiate the efficacy of anti-PDL-1 inhibition in pts with HCC. Methods: In this multi-centre (n = 10) study, pts with biopsy-confirmed HCC, PS ECOG < 1, Child-Pugh A, < 1 prior systemic therapies, receive 1 of escalating doses of AZD5069 (bid, po daily) with Durvalumab (1.5 gm iv on day 1) in 28-day cycles for up to 2 years to determine the recommended phase II dose using a Keyboard design, followed by an additional cohort of pts to determine the anti-tumor efficacy of this combination using a Simon’s two-stage design (min 18, max 35 pts; target objective response rate > 30%; unacceptable response rate < 10%). Dose limiting toxicities (DLTs) are assessed during cycle 1. Disease assessments are performed 8-weekly (12-weekly after 1 year). The 1st dose cohort has been completed with no DLTs. The 2nd dose cohort opened to recruitment in September 2022. Exploratory studies (blood; pre- & on-treatment tumor and non-malignant liver biopsies) include biomarkers of CXCR2 inhibition (blood); proof-of-mechanism (tumor: expression of CXCR2, PD-L1, PD-1, CD8, CD4, CD66b, CD69); proof-of-mechanism (blood: ctDNA); drug-induced changes of mRNA expression, CXCR2 ligands & signalling pathway genes, T-cell and myeloid cell pathways, neutrophil-associated genes; predictive biomarkers (blood and tumour) include biomarkers of the CXCR2/PD-L1 immune axis; aberrant CXCR2 signalling pathways; proliferation biomarkers and CD10 (neutrophils), CD68 (macrophages), CD103 (T-regs); tumour mutational status. This study is funded by a grant from Cancer Research UK (A29287) and is co-sponsored by University of Glasgow and NHS Greater Glasgow & Clyde. Study sites are supported by the Experimental Cancer Medicine Centre Network. AZD5069 and Durvalumab are provided by Astra Zeneca. Clinical trial information: 2020-003346-36 .

1317 A QUALITY IMPROVEMENT PROJECT AIMING TO ENHANCE THE RECOGNITION OF INPATIENT WEIGHT LOSS ON AN ELDERLY WARD

Background

Weight loss in the older adult is often multifactorial and can be associated with increased morbidity and mortality. Our quality improvement project focused on nutritional care of patients 75 years or older. This hospital has a standardised Nutrition and Hydration Policy based on NICE guidelines to prevent malnutrition in hospital inpatients including weighing patients every 72 hours, daily screening and food/hydration charts. Our project aimed to increase adherence, with a focus on increasing the percentage of patients being regularly weighed over a 6-month period to 90%.

Methods

Our stakeholder analysis highlighted the multidisciplinary nature of our project, particularly involving the healthcare assistants. The percentage of patients weighed within 72 hours was recorded weekly. The first PDSA cycle introduced the project and gained buy-in from the MDT, highlighting required weights in MDT meetings/board rounds. The second cycle included an education session for doctors. The third cycle involved a poster in each bay aiming to act as a prompt and promote patient and family involvement.

Results

Our run chart shows that following our first two PDSA cycles eight consecutive results were higher than the baseline (40% of patients weighed). Results ranged from 70-90%. Following the third intervention compliance returned to baseline but coincided with significant disruption to the ward structure and team. Our successful intervention of nutritional teaching was then repeated as a fourth PDSA cycle and the mean returned to 80%.

Conclusions

Nutritional care requires multidisciplinary involvement. The educational session had the most impact and in future could be delivered to additional MDT members. Disappointingly the poster did not stimulate patient or family participation. We would like to create an ethos on elderly wards where nutrition routinely features in ward-based comprehensive geriatric assessments. Future plans hope to further engage patients and families as visiting restrictions eased.

Biomarkers of systemic inflammation predict survival with first-line immune checkpoint inhibitors in non-small-cell lung cancer

INTRODUCTION

Pembrolizumab is an established first-line option for patients with advanced non-small-cell lung cancer (NSCLC) expressing programmed death-ligand 1 ≥50%. Durable responses are seen in a subset of patients; however, many derive little clinical benefit. Biomarkers of the systemic inflammatory response predict survival in NSCLC. We evaluated their prognostic significance in patients receiving first-line pembrolizumab for advanced NSCLC.

METHODS

Patients treated with first-line pembrolizumab for advanced NSCLC with programmed death-ligand 1 expression ≥50% at two regional Scottish cancer centres were identified. Pretreatment inflammatory biomarkers (white cell count, neutrophil count, neutrophil/lymphocyte ratio, platelet/lymphocyte ratio, albumin, prognostic nutritional index) were recorded. The relationship between these and progression-free survival (PFS) and overall survival (OS) were examined.

RESULTS

Data were available for 219 patients. On multivariate analysis, albumin and neutrophil count were independently associated with PFS (P < 0.001, P = 0.002, respectively) and OS (both P < 0.001). A simple score combining these biomarkers was explored. The Scottish Inflammatory Prognostic Score (SIPS) assigned 1 point each for albumin <35 g/l and neutrophil count >7.5 × 10⁹/l to give a three-tier categorical score. SIPS predicted PFS [hazard ratio 2.06, 95% confidence interval (CI) 1.68-2.52 (P < 0.001)] and OS [hazard ratio 2.33, 95% CI 1.86-2.92 (P < 0.001)]. It stratified PFS from 2.5 (SIPS2), to 8.7 (SIPS1) to 17.9 months (SIPS0) (P < 0.001) and OS from 5.1 (SIPS2), to 12.4 (SIPS1) to 28.7 months (SIPS0) (P < 0.001). The relative risk of death before 6 months was 2.96 (95% CI 1.98-4.42) in patients with SIPS2 compared with those with SIPS0-1 (P < 0.001).

CONCLUSIONS

SIPS, a simple score combining albumin and neutrophil count, predicts survival in patients with NSCLC receiving first-line pembrolizumab. Unlike many proposed prognostic scores, SIPS uses only routinely collected pretreatment test results and provides a categorical score. It stratifies survival across clinically meaningful time periods that may assist clinicians and patients with treatment decisions. We advocate validation of the prognostic utility of SIPS in this and other immune checkpoint inhibitor treatment settings.

Workforce Planning Models for Oral Health Care: A Scoping Review

BACKGROUND

For health care services to address the health care needs of populations and respond to changes in needs over time, workforces must be planned. This requires quantitative models to estimate future workforce requirements that take account of population size, oral health needs, evidence-based approaches to addressing needs, and methods of service provision that maximize productivity. The aim of this scoping review was to assess whether and how these 4 elements contribute to existing models of oral health workforce planning.

METHODS

A scoping review was conducted. MEDLINE, Embase, HMIC, and EconLit were searched, all via OVID. Additionally, gray literature databases were searched and key bodies and policy makers contacted. Workforce planning models were included if they projected workforce numbers and were specific to oral health. No limits were placed on country. A single reviewer completed initial screening of abstracts; 2 independent reviewers completed secondary screening and data extraction. A narrative synthesis was conducted.

RESULTS

A total of 4,009 records were screened, resulting in 42 included articles detailing 47 models. The workforce planning models varied significantly in their use of data on oral health needs, evidence-based services, and provider productivity, with most models relying on observed levels of service utilization and demand.

CONCLUSIONS

This review has identified quantitative workforce planning models that aim to estimate future workforce requirements. Approaches to planning the oral health workforce are not always based on deriving workforce requirements from population oral health needs. In many cases, requirements are not linked to population needs, while in models where needs are included, they are constrained by the existence and availability of the required data. It is critical that information systems be developed to effectively capture data necessary to plan future oral health care workforces in ways that relate directly to the needs of the populations being served.

KNOWLEDGE TRANSFER STATEMENT

Policy makers can use the results of this study when making decisions about the planning of oral health care workforces and about the data to routinely collect within health services. Collection of suitable data will allow for the continual improvement of workforce planning, leading to a responsive health service and likely future cost savings.

Serum Proteomics and Plasma Fibulin-3 in Differentiation of Mesothelioma From Asbestos-Exposed Controls and Patients With Other Pleural Diseases

INTRODUCTION

Malignant pleural mesothelioma (MPM) is difficult to diagnose. An accurate blood biomarker could prompt specialist referral or be deployed in future screening. In earlier retrospective studies, SOMAscan proteomics (Somalogic, Boulder, CO) and fibulin-3 seemed highly accurate, but SOMAscan has not been validated prospectively and subsequent fibulin-3 data have been contradictory.

METHODS

A multicenter prospective observational study was performed in 22 centers, generating a large intention-to-diagnose cohort. Blood sampling, processing, and diagnostic assessment were standardized, including a 1-year follow-up. Plasma fibulin-3 was measured using two enzyme-linked immunosorbent assays (CloudClone [used in previous studies] and BosterBio, Pleasanton, CA). Serum proteomics was measured using the SOMAscan assay. Diagnostic performance (sensitivity at 95% specificity, area under the curve [AUC]) was benchmarked against serum mesothelin (Mesomark, Fujirebio Diagnostics, Malvern, PA). Biomarkers were correlated against primary tumor volume, inflammatory markers, and asbestos exposure.

RESULTS

A total of 638 patients with suspected pleural malignancy (SPM) and 110 asbestos-exposed controls (AECs) were recruited. SOMAscan reliably differentiated MPM from AECs (75% sensitivity, 88.2% specificity, validation cohort AUC 0.855) but was not useful in patients with differentiating non-MPM SPM. Fibulin-3 (by BosterBio after failed CloudClone validation) revealed 7.4% and 11.9% sensitivity at 95% specificity in MPM versus non-MPM SPM and AECs, respectively (associated AUCs 0.611 [0.557-0.664], p = 0.0015) and 0.516 [0.443-0.589], p = 0.671), both inferior to mesothelin. SOMAscan proteins correlated with inflammatory markers but not with asbestos exposure. Neither biomarker correlated with tumor volume.

CONCLUSIONS

SOMAscan may prove useful as a future screening test for MPM in asbestos-exposed persons. Neither fibulin-3 nor SOMAscan should be used for diagnosis or pathway stratification.

Durvalumab (MEDI 4736) in combination with extended neoadjuvant regimens in rectal cancer: a study protocol of a randomised phase II trial (PRIME-RT)

BACKGROUND

Advances in multi-modality treatment of locally advanced rectal cancer (LARC) have resulted in low local recurrence rates, but around 30% of patients will still die from distant metastatic disease. In parallel, there is increasing recognition that with radiotherapy and systemic treatment, some patients achieve a complete response and may avoid surgical resection, including in many cases, the need for a permanent stoma. Extended neoadjuvant regimes have emerged to address these concerns. The inclusion of immunotherapy in the neoadjuvant setting has the potential to further enhance this strategy by priming the local immune microenvironment and engaging the systemic immune response.

METHODS

PRIME-RT is a multi-centre, open label, phase II, randomised trial for patients with newly diagnosed LARC. Eligible patients will be randomised to receive either: short course radiotherapy (25 Gray in 5 fractions over one week) with concomitant durvalumab (1500 mg administered intravenously every 4 weeks), followed by FOLFOX (85 mg/m2 oxaliplatin, 350 mg folinic acid and 400 mg/m2 bolus 5-fluorouracil (5-FU) given on day 1 followed by 2400 mg/m2 5-FU infusion over 46-48 h, all administered intravenously every 2 weeks), and durvalumab, or long course chemoradiotherapy (50 Gray to primary tumour in 25 fractions over 5 weeks with concomitant oral capecitabine 825 mg/m2 twice per day on days of radiotherapy) with durvalumab followed by FOLFOX and durvalumab. The primary endpoint is complete response rate in each arm. Secondary endpoints include treatment compliance, toxicity, safety, overall recurrence, proportion of patients with a permanent stoma, and survival. The study is translationally rich with collection of bio-specimens prior to, during, and following treatment in order to understand the molecular and immunological factors underpinning treatment response. The trial opened and the first patient was recruited in January 2021. The main trial will recruit up to 42 patients with LARC and commence after completion of a safety run-in that will recruit at least six patients with LARC or metastatic disease.

DISCUSSION

PRIME-RT will explore if adding immunotherapy to neoadjuvant radiotherapy and chemotherapy for patients with LARC can prime the tumour microenvironment to improve complete response rates and stoma free survival. Sequential biopsies are a key component within the trial design that will provide new knowledge on how the tumour microenvironment changes at different time-points in response to multi-modality treatment. This expectation is that the trial will provide information to test this treatment within a large phase clinical trial. Trial registration Clinicaltrials.gov NCT04621370 (Registered 9th Nov 2020) EudraCT number 2019-001471-36 (Registered 6th Nov 2020).

SAPROCAN: Saracatinib (AZD0530) and docetaxel in metastatic,castrate-refractory prostate cancer (mCRPC)—A phase I/randomized phase II study by the United Kingdom National Cancer Research Institute Prostate Group

107

Background: Saracatinib is an orally-available, highly selective inhibitor of Abl and Src family members. It is an ATP-competitive tyrosine kinase inhibitor. Preclinical data suggested that the combination of a Src kinase inhibitor and docetaxel is synergistic, and Src kinase activity was also implicated in the bone’s metabolic response to cancer metastases. Methods: Patients with mCRPC were initially enrolled in an open-label, dose escalation phase I trial of oral saracatinib (cohorts of 50mg, 125mg and 175mg daily) with docetaxel (75mg/m2) in a 3+3 design. Subsequent patients were randomised 1:1 between saracatinib 175mg and placebo once daily. Pharmacokinetics (PK) of docetaxel were explored in phase I to exclude significant drug-drug interaction. The primary endpoint of phase II was biochemical or radiographic progression free survival (PFS). Secondary endpoints included overall survival (OS), safety and tolerability. Changes in circulating tumour cell (CTC) counts were also measured. The phase II was designed with a 1-sided alpha of 0.2 with 90% power to detect a hazard ratio (HR) for PFS of 0.67. Results: 10 patients were enrolled in phase I and 142 in the randomised phase II. No dose limiting toxicities or PK interactions were observed and the recommended dose for phase II was 175mg saracatinib daily and 75mg/m2docetaxel every 21 days. In phase II, the HR for PFS was 1.35 (80% confidence interval (CI) 1.07 to 1.70). The HR for OS was 1.42 (1.08 – 1.81). 41/71 and 29/71 experienced treatment related toxicities of grade 3 or above in the saracatinib and placebo arms respectively. 10/19 (53%) and 14/27 (52%) evaluable patients demonstrated a reduction in CTCs from ≥5 to < 5 /7.5ml blood at 6 weeks after starting saracatinib and placebo respectively. Conclusions: Saracatinib, in combination with docetaxel, adds toxicity and not efficacy in mCRPC. This combination should not be developed further in combination with docetaxel in the treatment of mCRPC. Clinical trial information: ISRCTN22566729.

Optimisation of an Electrochemical DNA Sensor for Measuring KRAS G12D and G13D Point Mutations in Different Tumour Types

Circulating tumour DNA (ctDNA) is widely used in liquid biopsies due to having a presence in the blood that is typically in proportion to the stage of the cancer and because it may present a quick and practical method of capturing tumour heterogeneity. This paper outlines a simple electrochemical technique adapted towards point-of-care cancer detection and treatment monitoring from biofluids using a label-free detection strategy. The mutations used for analysis were the KRAS G12D and G13D mutations, which are both important in the initiation, progression and drug resistance of many human cancers, leading to a high mortality rate. A low-cost DNA sensor was developed to specifically investigate these common circulating tumour markers. Initially, we report on some developments made in carbon surface pre-treatment and the electrochemical detection scheme which ensure the most sensitive measurement technique is employed. Following pre-treatment of the sensor to ensure homogeneity, DNA probes developed specifically for detection of the KRAS G12D and G13D mutations were immobilized onto low-cost screen printed carbon electrodes using diazonium chemistry and 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride/N-hydroxysuccinimide coupling. Prior to electrochemical detection, the sensor was functionalised with target DNA amplified by standard and specialist PCR methodologies (6.3% increase). Assay development steps and DNA detection experiments were performed using standard voltammetry techniques. Sensitivity (as low as 0.58 ng/μL) and specificity (>300%) was achieved by detecting mutant KRAS G13D PCR amplicons against a background of wild-type KRAS DNA from the representative cancer sample and our findings give rise to the basis of a simple and very low-cost system for measuring ctDNA biomarkers in patient samples. The current time to receive results from the system was 3.5 h with appreciable scope for optimisation, thus far comparing favourably to the UK National Health Service biopsy service where patients can wait for weeks for biopsy results.

Developing a Low-Cost, Simple-to-Use Electrochemical Sensor for the Detection of Circulating Tumour DNA in Human Fluids

It is well-known that two major issues, preventing improved outcomes from cancer are late diagnosis and the evolution of drug resistance during chemotherapy, therefore technologies that address these issues can have a transformative effect on healthcare workflows. In this work we present a simple, low-cost DNA biosensor that was developed specifically to detect mutations in a key oncogene (KRAS). The sensor employed was a screen-printed array of carbon electrodes, used to perform parallel measurements of DNA hybridisation. A DNA amplification reaction was developed with primers for mutant and wild type KRAS sequences which amplified target sequences from representative clinical samples to detectable levels in as few as twenty cycles. High levels of sensitivity were demonstrated alongside a clear exemplar of assay specificity by showing the mutant KRAS sequence was detectable against a significant background of wild type DNA following amplification and hybridisation on the sensor surface. The time to result was found to be 3.5 h with considerable potential for optimisation through assay integration. This quick and versatile biosensor has the potential to be deployed in a low-cost, point-of-care test where patients can be screened either for early diagnosis purposes or monitoring of response to therapy.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

A randomised phase II trial of hydroxychloroquine and imatinib versus imatinib alone for patients with chronic myeloid leukaemia in major cytogenetic response with residual disease

In chronic-phase chronic myeloid leukaemia (CP-CML), residual BCR-ABL1+ leukaemia stem cells are responsible for disease persistence despite TKI. Based on in vitro data, CHOICES (CHlorOquine and Imatinib Combination to Eliminate Stem cells) was an international, randomised phase II trial designed to study the safety and efficacy of imatinib (IM) and hydroxychloroquine (HCQ) compared with IM alone in CP-CML patients in major cytogenetic remission with residual disease detectable by qPCR. Sixty-two patients were randomly assigned to either arm. Treatment 'successes' was the primary end point, defined as ≥0.5 log reduction in 12-month qPCR level from trial entry. Selected secondary study end points were 24-month treatment 'successes', molecular response and progression at 12 and 24 months, comparison of IM levels, and achievement of blood HCQ levels >2000 ng/ml. At 12 months, there was no difference in 'success' rate (p = 0.58); MMR was achieved in 80% (IM) vs 92% (IM/HCQ) (p = 0.21). At 24 months, the 'success' rate was 20.8% higher with IM/HCQ (p = 0.059). No patients progressed. Seventeen serious adverse events, including four serious adverse reactions, were reported; diarrhoea occurred more frequently with combination. IM/HCQ is tolerable in CP-CML, with modest improvement in qPCR levels at 12 and 24 months, suggesting autophagy inhibition maybe of clinical value in CP-CML.

Discovery of [11C]MK-6884: A Positron Emission Tomography (PET) Imaging Agent for the Study of M4Muscarinic Receptor Positive Allosteric Modulators (PAMs) in Neurodegenerative Diseases

The measurement of receptor occupancy (RO) using positron emission tomography (PET) has been instrumental in guiding discovery and development of CNS directed therapeutics. We and others have investigated muscarinic acetylcholine receptor 4 (M4) positive allosteric modulators (PAMs) for the treatment of symptoms associated with neuropsychiatric disorders. In this article, we describe the synthesis, in vitro, and in vivo characterization of a series of central pyridine-related M4 PAMs that can be conveniently radiolabeled with carbon-11 as PET tracers for the in vivo imaging of an allosteric binding site of the M4 receptor. We first demonstrated its feasibility by mapping the receptor distribution in mouse brain and confirming that a lead molecule 1 binds selectively to the receptor only in the presence of the orthosteric agonist carbachol. Through a competitive binding affinity assay and a number of physiochemical properties filters, several related compounds were identified as candidates for in vivo evaluation. These candidates were then radiolabeled with ¹¹C and studied in vivo in rhesus monkeys. This research eventually led to the discovery of the clinical radiotracer candidate [¹¹C]MK-6884.

Pharmacological Characterization of the Novel and Selective α7 Nicotinic Acetylcholine Receptor-Positive Allosteric Modulator BNC375

Treatments for cognitive deficits associated with central nervous system (CNS) disorders such as Alzheimer disease and schizophrenia remain significant unmet medical needs that incur substantial pressure on the health care system. The α7 nicotinic acetylcholine receptor (nAChR) has garnered substantial attention as a target for cognitive deficits based on receptor localization, robust preclinical effects, genetics implicating its involvement in cognitive disorders, and encouraging, albeit mixed, clinical data with α7 nAChR orthosteric agonists. Importantly, previous orthosteric agonists at this receptor suffered from off-target activity, receptor desensitization, and an inverted U-shaped dose-effect curve in preclinical assays that limit their clinical utility. To overcome the challenges with orthosteric agonists, we have identified a novel selective α7 positive allosteric modulator (PAM), BNC375. This compound is selective over related receptors and potentiates acetylcholine-evoked α7 currents with only marginal effect on the receptor desensitization kinetics. In addition, BNC375 enhances long-term potentiation of electrically evoked synaptic responses in rat hippocampal slices and in vivo. Systemic administration of BNC375 reverses scopolamine-induced cognitive deficits in rat novel object recognition and rhesus monkey object retrieval detour (ORD) task over a wide range of exposures, showing no evidence of an inverted U-shaped dose-effect curve. The compound also improves performance in the ORD task in aged African green monkeys. Moreover, ex vivo ¹³C-NMR analysis indicates that BNC375 treatment can enhance neurotransmitter release in rat medial prefrontal cortex. These findings suggest that α7 nAChR PAMs have multiple advantages over orthosteric α7 nAChR agonists for the treatment of cognitive dysfunction associated with CNS diseases. SIGNIFICANCE STATEMENT: BNC375 is a novel and selective α7 nicotinic acetylcholine receptor (nAChR) positive allosteric modulator (PAM) that potentiates acetylcholine-evoked α7 currents in in vitro assays with little to no effect on the desensitization kinetics. In vivo, BNC375 demonstrated robust procognitive effects in multiple preclinical models across a wide exposure range. These results suggest that α7 nAChR PAMs have therapeutic potential in central nervous system diseases with cognitive impairments.

30 The Role of A Virtual Clinic in Reducing Waiting Times for Out-Patient Follow-Up

Topic

Hospital admissions for older people are increasing with subsequent pressure on out-patient (OP) clinics. By early 2018, 350 patients were waiting up to 6 months for follow-up, with limited capacity in existing clinics. There were concerns regarding potential harm to patients from delayed review of significant results.

Intervention

A working group considered options for managing the OP waiting list. We decided to pilot a fortnightly virtual clinic (VC) where cases were reviewed without the patient present. All patients awaiting results were listed for the VC rather than routine OP. Each VC had 50 patients listed. Patient’s GP received a clear action plan. Clinic rules were modified as issues were identified. Links with other specialities evolved reducing the number of missing results. Data was analysed for 50% of consultations between January 2018 and March 2019.

Improvement

311 VC appointments were reviewed: 207 in 2018 and 104 up to March 2019. Maximum 25 cases could be completed per clinic, additional sessions cleared initial backlog within 3 months. Completion time/case ranged from 2-15 minutes depending on complexity. Main reason for VC was test results: 82% in 2018, increasing to 93% in 2019. 61% in 2018, 80% in 2019 were discharged directly from VC. 20% required a 2nd VC for outstanding results. OP review post-VC fell from 16% in 2018 to just 2% in 2019. General OP requirements fell from 24hrs to 10 hours/ week as a result of VCs, releasing consultants for other clinical areas.

Discussion

VCs are an effective means of reviewing outstanding results from recent admissions and OP consultations. Routine listing of patients with outstanding investigations provides a safety net. Most results are normal and do not require follow-up. Repeat CXRs at 6 weeks continue to be requested for severely frail people who are unlikely to benefit.

A phase I study of olaparib in combination with capecitabine-based chemoradiation (CRT) in patients (pts) with locally advanced pancreatic cancer (LAPC)

709

Background: Olaparib is a potent inhibitor of PARP-1, which has a critical role in signalling DNA single strand breaks (SSB) as part of the base excision repair pathway, and may have radio-sensitizing effects due to impaired resolution of radiation induced SSB. We hypothesize that O may potentiate the effects of X-CRT in pts with LAPC. Methods: Eligible pts with LAPC, ECOG < 1, tumor diameter < 6cm, with stable disease (SD) or response after 12 weeks’ induction chemotherapy, were treated with 1 of 4 escalating doses of O given bid po starting on day -3, and then in combination with X (830 mg/m2 bid) and radiation (50·4 Gy in 28 fractions) all administered Mon-Fri. Dose limiting toxicities (DLT) were determined on clinical and lab toxicity assessments (NCI-CTC AE v4.03) performed weekly from the start of O until completion of O plus X-CRT (i.e. 6 weeks). Dose escalation continued with a rolling-six design until the Maximum Tolerated Dose (MTD) was reached. Blood samples for PK analyses of O and PD measurement (inhibition of PARP activity) were collected on day -3 (O monotherapy) and during week 1 of O + X-CRT. Results: 18 pts, (9 m, 9 f, ECOG 0/1 [n=6/12]), age range 49-81 (median=70) years, with histologic (14) or cytologic (4) proven LAPC, had received induction chemotherapy with gemcitabine [GEM] (n=2), GEM + X (12), or FOLFIRINOX (3) with partial response (n=4) or stable disease (14). Pts received 50 (3), 100 (4), 150 (6), or 200 (5) mgs bid of O with X+CRT. DLTs were observed in 2 pts (both at 200mgs bid): 1 pt with grade 3 nausea (on optimal anti-emetics) and grade 3 fatigue, 1 pt with grade 3 anorexia. 6 pts were subsequently recruited at 150mgs bid with no DLTs. No pts had complete response, 2 pts had partial response (1 pt each at 100 and 150 mgs bid) and 1 pt (at 100 mgs bid) had progressive disease; the remaining 14 pts had SD. Conclusions: The recommended dose (RP2) of O is 150mgs bid when given in combination with X + CRT in LAPC. Recruitment of up to 12 pts with borderline operable LAPC at the RP2 is ongoing. PK analyses of O, PD studies (PARP inhibition – PBMCs; cytokeratin 18 – serum; γH2AX foci – hair follicles), and exploratory predictive marker studies (tumor – NGS; RNA exome sequencing) are ongoing. Clinical trial information: ISRCTN10361292.

The Patient Concerns Inventory integrated as part of routine head and neck cancer follow-up consultations: frequency, case-mix, and items initiated by the patient

Introduction The National Institute for Health and Care Excellence guidance Improving Supportive and Palliative Care for Adults with Cancer (2004) and the Cancer Reform Strategy (2007) support the premise that assessment and discussion of patients' needs for physical, social, psychological, and spiritual wellbeing should be undertaken during oncology follow-up. We report the use of the Patient Concerns Inventory in a routine head and neck cancer clinic setting over a seven-year period, summarising the number of available clinics, the number of patients completing the inventory within a clinic, the range of clinical characteristics and the concerns they wanted to discuss. Methods The data were analysed from oncology follow-up clinics between 1 August 2007 and 10 December 2014. Audit approval was given by the Clinical Audit Department, University Hospital Aintree. Results There were 386 patients with 1198 inventories completed at 220 clinics, median 6 (range 4-7) per clinic. The most common concerns raised by patients across all the clinic consultations were dry mouth (34%), fear of recurrence (33%), sore mouth (26%), dental health (25%), chewing (22%) and fatigue/tiredness (21%). Conclusions The incorporation of the Patient Concerns Inventory as part of routine oncology clinics allows for a more patient initiated and focused consultation available to the majority of patients throughout their follow-up. The inventory allows for greater opportunity to provide holistic targeted multiprofessional intervention and support.

Tablet computers in assessing performance in a high stakes exam: opinion matters

Background Tablet computers have emerged as a tool to capture, process and store data in examinations, yet evidence relating to their acceptability and usefulness in assessment is limited. Methods We performed an observational study to explore opinions and attitudes relating to tablet computer use in recording performance in a final year objective structured clinical examination at a single UK medical school. Examiners completed a short questionnaire encompassing background, forced-choice and open questions. Forced choice questions were analysed using descriptive statistics and open questions by framework analysis. Results Ninety-two (97% response rate) examiners completed the questionnaire of whom 85% had previous use of tablet computers. Ninety per cent felt checklist mark allocation was 'very/quite easy', while approximately half considered recording 'free-type' comments was 'easy/very easy'. Greater overall efficiency of marking and resource savings were considered the main advantages of tablet computers, while concerns relating to technological failure and ability to record free type comments were raised. Discussion In a context where examiners were familiar with tablet computers, they were preferred to paper checklists, although concerns were raised. This study adds to the limited literature underpinning the use of electronic devices as acceptable tools in objective structured clinical examinations.

A phase I trial of the oral hedgehog inhibitor taladegib (LY2940680) in combination with weekly paclitaxel in patients with advanced, solid tumours

2594

Background: Aberrant Hedgehog (Hh) signaling is implicated in carcinogenesis and is associated with poor prognosis in multiple tumours types. Hh inhibitors increase sensitivity to paclitaxel in taxane-resistant cell lines. Taladegib is an orally bioavailable, potent inhibitor of Smoothened, a key Hh pathway component, with activity in basal cell carcinoma. The single agent recommended dose is 400mg od. We present the dose escalation phase of a phase I study of weekly paclitaxel with oral taladegib. Methods: Primary objective: determine the dose limiting toxicity (DLT) and maximum tolerated dose (MTD) of taladegib on a continuous oral daily dosing regimen in combination with paclitaxel (80mg/m2, iv, day 1, 8 and 15 q 28) in patients with advanced solid cancers. Secondary objectives: assess the safety and tolerability, determine the recommended phase II dose (RP2D), and evaluate the pharmacokinetics of taladegib and paclitaxel. Exploratory objective: assess preliminary efficacy. A standard 3 + 3 dose escalation design was used. All patients received up to 6 cycles of paclitaxel. In addition, successive cohorts received continuous oral taladegib continued until progression or unacceptable toxicity as follows: dose level 1: 100mg od; 2: 200mg od; 3: 400mg od. Results: No DLTs were seen at dose level 1 or in the first 3 patients at dose level 2. 3 DLTs of grade 2 neuropathy were seen at dose level 3 (400mg taladegib); therefore, dose level 2 was expanded to 6 patients. No DLT was seen in the fourth patient and 2 additional patients have started treatment. After the DLT period 2 patients developed G2 and 4 developed G1 neuropathy. Other non DLT, drug-related G3 toxicities: uncomplicated neutropenia x2, muscle cramp x1 and fatigue x1. To date, 3 patients have had partial responses. Conclusions: The combination of daily oral taladegib and weekly paclitaxel is feasible. DLT of G2 neuropathy was seen at 400mg. Promising activity has been seen in solid tumours. A dose expansion cohort is due to commence in high grade ovarian carcinoma. ISRCTN No:ISRCTN15903698 Eudract Ref:2014-004695-37 Funded by Cancer Research UK C8361/A18775 and Ignyta. Sponsored by NHS Greater Glasgow and Clyde. Clinical trial information: ISRCTN15903698.

Iterative Focused Screening with Biological Fingerprints Identifies Selective Asc-1 Inhibitors Distinct from Traditional High Throughput Screening

N-methyl-d-aspartate receptors (NMDARs) mediate glutamatergic signaling that is critical to cognitive processes in the central nervous system, and NMDAR hypofunction is thought to contribute to cognitive impairment observed in both schizophrenia and Alzheimer's disease. One approach to enhance the function of NMDAR is to increase the concentration of an NMDAR coagonist, such as glycine or d-serine, in the synaptic cleft. Inhibition of alanine-serine-cysteine transporter-1 (Asc-1), the primary transporter of d-serine, is attractive because the transporter is localized to neurons in brain regions critical to cognitive function, including the hippocampus and cortical layers III and IV, and is colocalized with d-serine and NMDARs. To identify novel Asc-1 inhibitors, two different screening approaches were performed with whole-cell amino acid uptake in heterologous cells stably expressing human Asc-1: (1) a high-throughput screen (HTS) of 3 M compounds measuring ³⁵S l-cysteine uptake into cells attached to scintillation proximity assay beads in a 1536 well format and (2) an iterative focused screen (IFS) of a 45 000 compound diversity set using a ³H d-serine uptake assay with a liquid scintillation plate reader in a 384 well format. Critically important for both screening approaches was the implementation of counter screens to remove nonspecific inhibitors of radioactive amino acid uptake. Furthermore, a 15 000 compound expansion step incorporating both on- and off-target data into chemical and biological fingerprint-based models for selection of additional hits enabled the identification of novel Asc-1-selective chemical matter from the IFS that was not identified in the full-collection HTS.

Diagnostic and Prognostic Biomarkers in the Rational Assessment of Mesothelioma (DIAPHRAGM) study: protocol of a prospective, multicentre, observational study

INTRODUCTION

Malignant pleural mesothelioma (MPM) is an asbestos-related cancer, which is difficult to diagnose. Thoracoscopy is frequently required but is not widely available. An accurate, non-invasive diagnostic biomarker would allow early specialist referral, limit diagnostic delays and maximise clinical trial access. Current markers offer insufficient sensitivity and are not routinely used. The SOMAmer proteomic classifier and fibulin-3 have recently demonstrated sensitivity and specificity exceeding 90% in retrospective studies. DIAPHRAGM (Diagnostic and Prognostic Biomarkers in the Rational Assessment of Mesothelioma) is a suitably powered, multicentre, prospective observational study designed to determine whether these markers provide clinically useful diagnostic and prognostic information.

METHODS AND ANALYSIS

Serum and plasma (for SOMAscan and fibulin-3, respectively) will be collected at presentation, prior to pleural biopsy/pleurodesis, from 83 to 120 patients with MPM, at least 480 patients with non-MPM pleural disease and 109 asbestos-exposed controls. Final numbers of MPM/non-MPM cases will depend on the incidence of MPM in the study population (estimated at 13-20%). Identical sampling and storage protocols will be used in 22 recruiting centres and histological confirmation sought in all cases. Markers will be measured using the SOMAscan proteomic assay (SomaLogic) and a commercially available fibulin-3 ELISA (USCN Life Science). The SE in the estimated sensitivity and specificity will be <5% for each marker and their performance will be compared with serum mesothelin. Blood levels will be compared with paired pleural fluid levels and MPM tumour volume (using MRI) in a nested substudy. The prognostic value of each marker will be assessed and a large bioresource created.

ETHICS AND DISSEMINATION

The study has been approved by the West of Scotland Research Ethics Committee (Ref: 13/WS/0240). A Trial Management Group meets on a monthly basis. Results will be published in peer-reviewed journals, presented at international meetings and disseminated to patient groups.

TRIAL REGISTRATION NUMBER

ISRCTN10079972, Pre-results.

Are we exposing patients with a mildly elevated faecal calprotectin to unnecessary investigations?

OBJECTIVE

Faecal calprotectin (FC) is a non-invasive marker used to differentiate irritable bowel syndrome from inflammatory bowel disease (IBD). However, false positives are common. We sought to determine the diagnostic yield of investigation in patients presenting with new lower gastrointestinal (GI) symptoms and a mildly elevated FC (100-200 µg/g).

DESIGN

Retrospective study of electronic patient records.

PATIENTS

Patients aged 16-50 years with new lower GI symptoms and an FC 100-200 µg/g were identified from our biochemistry laboratory database between September 2009 and 2011. Patients were excluded if they had a previous FC >200 µg/g, were taking non-steroidal anti-inflammatory drugs (NSAIDs), had IBD, positive stool cultures or 'alarm' symptoms.

SETTING

Secondary care gastroenterology clinics.

RESULTS

161 patients (103 female patients) were identified. Mean age was 37.3 years with a mean FC of 147 µg/g. 398 endoscopic, radiological and histological investigations were undertaken in 141 patients (an average of 2.8 investigations per patient). 131 colonoscopies were performed with abnormalities in only 24 (18.3%). In patients with a macroscopically normal upper GI endoscopy and colonoscopy, the diagnostic yield of any further investigation was only 7.3%. The negative predictive value (NPV) of an FC 100-200 µg/g was 86.7% for any pathology and 97.5% for significant luminal pathology (IBD, advanced adenoma or colorectal carcinoma). After a mean follow-up of 172.4 weeks, IBD was the final diagnosis in only 4 (2.5%) of patients.

CONCLUSIONS

In adult patients under 50 years old presenting with new lower GI symptoms, the NPV of an FC between 100 and 200 µg/g in excluding significant organic GI disease is high.

Ten-minute chat

Fiona Thomson took time away from Pets'n'Vets, Blantyre, South Lanarkshire, to spend two weeks volunteering in Blantyre, Malawi, as part of Mission Rabies' first trip to Africa. She spoke to Vet Record Careers just before departing for Malawi on May 14.

Emergency management of paediatric status epilepticus in Australia and New Zealand: practice patterns in the context of clinical practice guidelines

AIMS

To establish current acute seizure management through a review of clinical practice guidelines (CPGs) and reported physician management in the 11 largest paediatric emergency departments in Australia (n= 9) and New Zealand (n= 2) within the Paediatric Research in Emergency Departments International Collaborative (PREDICT) network, and to compare this with Advanced Paediatric Life Support (APLS) guidelines and existing evidence.

METHODS

(i) Review of CPGs for acute seizure management at PREDICT sites. (ii) A standardised anonymous survey of senior emergency doctors at PREDICT sites investigating management of status epilepticus (SE).

RESULTS

Ten sites used seven different seizure CPGs. One site had no seizure CPG. First line management was with benzodiazepines (10 sites). Second line and subsequent management included phenytoin (10), phenobarbitone (10), thiopentone (9), paraldehyde (6) and midazolam infusion (5). Of 83 available consultants, 78 (94%) responded. First line management of SE without intravenous (IV) access included diazepam per rectum (PR) (49%), and midazolam intramuscular (41%) and via the buccal route (9%). First line management of SE with IV access included midazolam IV (50%) and diazepam IV (44%). The second line agent was phenytoin (88%); third line agents were phenobarbitone (33%), thiopentone and intubation (32%), paraldehyde PR (22%) and midazolam infusion (6%). Fourth line agents were thiopentone and intubation (60%), phenobarbitone (16%), midazolam infusion (13%) and paraldehyde (9%).

CONCLUSIONS

Initial seizure management by CPG recommendations and reported physician practice was broadly similar across PREDICT sites and consistent with APLS guidelines. Practice was variable for second/third line SE management. Areas of controversy would benefit from multi-centred trials.

Blockade of the V(1b) receptor reduces ACTH, but not corticosterone secretion induced by stress without affecting basal hypothalamic-pituitary-adrenal axis activity

Vasopressin (AVP), produced in parvocellular neurons of the hypothalamic paraventricular nucleus, regulates, together with CRH, pituitary ACTH secretion. The pituitary actions of AVP are mediated through the G protein receptor V(1b) (V(1b)|R). In man, hyperactivity of the hypothalamic-pituitary-adrenal axis has been associated with depression and other stress-related conditions. There are also clinical data suggesting a role for AVP in the dysfunctional HPA axis described in some depressed patients. In this study, we have investigated the effect of a recently synthesised selective antagonist of the V(1b)R both on exogenous AVP-induced ACTH and corticosterone secretion, and on basal and stress-induced pituitary-adrenal activity. Adult male Sprague-Dawley rats treated with the V(1b)R antagonist (Org, 30 mg/kg, s.c.) or vehicle (5% mulgofen in 0.9% saline, 2 ml/kg, s.c.). We found that blockade of the V(1b)R reduced the increase in both ACTH and corticosterone secretion induced by AVP (100 ng, i.v.). The same treatment had no effect either on basal ACTH and corticosterone levels or on the ultradian or diurnal rhythms of corticosterone secretion. Acute administration of the V(1b)R antagonist reduced ACTH secretion following both restraint and lipopolysaccharide, but did not antagonise the ACTH response to noise. The same treatment did not reduce corticosterone secretion in response to any of the three stressors used in this study. Our results confirm that this compound is an antagonist of the V(1b)R in the rat, and that its ability to reduce stress-induced ACTH responses is stressor dependent with differential modulation of pituitary and adrenal responses.

Paediatric acute asthma management in Australia and New Zealand: practice patterns in the context of clinical practice guidelines

OBJECTIVES

To compare clinical practice guideline (CPG) recommendations and reported physician management of acute paediatric asthma in the 11 largest paediatric emergency departments, all of which have CPGs, in Australia (n = 9) and New Zealand (n = 2). All 11 sites participate in the Paediatric Research in Emergency Departments International Collaborative (PREDICT) research network.

METHODS

(a) A review of CPGs for acute childhood asthma from all PREDICT sites. (b) A standardised anonymous survey of senior emergency doctors at PREDICT sites investigating management of acute childhood asthma.

RESULTS

CPGs for mild to moderate asthma were similar across sites and based on salbutamol delivery by metered dose inhaler with spacer and oral prednisolone. In severe to critical asthma, differences between sites were common and related to recommendations for: ipratropium use; metered-dose inhaler versus nebulised delivery of salbutamol in severe asthma; use of intravenous aminophylline, intravenous magnesium and dosing of intravenous salbutamol in critical asthma. The questionnaire (78 of 83 doctors responded) also revealed significant differences between doctors in the treatment of moderate to severe asthma. Ipratropium was used for moderate asthma by 42%. For severe to critical asthma, nebulised delivery of salbutamol was preferred by 79% of doctors over metered dose inhalers. For critical asthma, doctors reported using intravenous aminophylline in 45%, intravenous magnesium in 55%, and intravenous salbutamol in 87% of cases. Thirty-nine different dosing regimens for intravenous salbutamol were reported.

CONCLUSIONS

CPG recommendations and reported physician practice for mild to moderate paediatric asthma management were broadly similar across PREDICT sites and consistent with national guidelines. Practice was highly variable for severe to critical asthma and probably reflects limitations of available evidence. Areas of controversy, in particular the comparative efficacy of intravenous bronchodilators, would benefit from multi-centre trials. Collaborative development of CPGs should be considered.

Effect of the glucocorticoid receptor antagonist Org 34850 on basal and stress-induced corticosterone secretion

The activity of the hypothalamic-pituitary-adrenal (HPA) axis is characterised both by an ultradian pulsatile pattern of glucocorticoid secretion and an endogenous diurnal rhythm. Glucocorticoid feedback plays a major role in regulating HPA axis activity and this mechanism occurs via two different receptors: mineralocorticoid (MR) and glucocorticoid receptors (GR). In the present study, the effects of both acute and subchronic treatment with the GR antagonist Org 34850 on basal and stress-induced HPA axis activity in male rats were evaluated. To investigate the effect of Org 34850 on basal diurnal corticosterone rhythm over the 24-h cycle, an automated blood sampling system collected samples every 10 min. Acute injection of Org 34850 (10 mg/kg, s.c.) did not affect basal or stress-induced corticosterone secretion, but was able to antagonise the inhibitory effect of the glucocorticoid agonist methylprednisolone on stress-induced corticosterone secretion. However, 5 days of treatment with Org 34850 (10 mg/kg, s.c., two times a day), compared to rats treated with vehicle (5% mulgofen in 0.9% saline, 1 ml/kg, s.c.), increased corticosterone secretion over the 24-h cycle and resulted in changes in the pulsatile pattern of hormone release, but had no significant effect on adrenocorticotrophic hormone secretion or on stress-induced corticosterone secretion. Subchronic treatment with Org 34850 did not alter GR mRNA expression in the hippocampus, paraventricular nucleus of the hypothalamus or anterior-pituitary, or MR mRNA expression in the hippocampus. Our data suggest that a prolonged blockade of GRs is required to increase basal HPA axis activity. The changes observed here with ORG 34850 are consistent with inhibition of GR-mediated negative feedback of the HPA axis. In light of the evidence showing an involvement of dysfunctional HPA axis in the pathophysiology of depression, Org 34850 could be a potential treatment for mood disorders.

Innovative approaches for the treatment of depression: targeting the HPA axis

Altered activity of the hypothalamic pituitary adrenal (HPA) axis is one of the most commonly observed neuroendocrine abnormalities in patients suffering from major depressive disorder (MDD). Altered cortisol secretion can be found in as many as 80% of depressed patients. This observation has led to intensive clinical and preclinical research aiming to better understand the molecular mechanisms which underlie the alteration of the HPA axis responsiveness in depressive illness. Dysfunctional glucocorticoid receptor (GR) mediated negative feedback regulation of cortisol levels and changes in arginine vasopressin (AVP)/vasopressin V1b receptor and corticotrophin-releasing factor/CRF1 receptor regulation of adrenocotricotrophin (ACTH) release have all been implicated in over-activity of the HPA axis. Agents that intervene with the mechanisms involved in (dys)regulation of cortisol synthesis and release are under investigation as possible therapeutic agents. The current status of some of these approaches is described in this review.

Allosteric modulation of the cannabinoid CB1 receptor

We investigated the pharmacology of three novel compounds, Org 27569 (5-chloro-3-ethyl-1H-indole-2-carboxylic acid [2-(4-piperidin-1-yl-phenyl)-ethyl]-amide), Org 27759 (3-ethyl-5-fluoro-1H-indole-2-carboxylic acid [2-94-dimethylamino-phenyl)-ethyl]-amide), and Org 29647 (5-chloro-3-ethyl-1H-indole-2-carboxylic acid (1-benzyl-pyrrolidin-3-yl)-amide, 2-enedioic acid salt), at the cannabinoid CB1 receptor. In equilibrium binding assays, the Org compounds significantly increased the binding of the CB1 receptor agonist [3H]CP 55,940 [(1R,3R,4R)-3-[2-hydroxy-4-(1,1-dimethylheptyl)phenyl]-4-(3-hydroxypropyl)cyclohexan-1-ol], indicative of a positively cooperative allosteric effect. The same compounds caused a significant, but incomplete, decrease in the specific binding of the CB1 receptor inverse agonist [3H]SR 141716A [N-(piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboximide hydrochloride], indicative of a limited negative binding cooperativity. Analysis of the data according to an allosteric ternary complex model revealed that the estimated affinity of each Org compound was not significantly different when the radioligand was [3H]CP 55,940 or [3H]SR 141716A. However, the estimated cooperatively factor for the interaction between modulator and radioligand was greater than 1 when determined against [3H]CP 55,940 and less than 1 when determined against [3H]SR 141716A. [3H]CP 55,940 dissociation kinetic studies also validated the allosteric nature of the Org compounds, because they all significantly decreased radioligand dissociation. These data suggest that the Org compounds bind allosterically to the CB1 receptor and elicit a conformational change that increases agonist affinity for the orthosteric binding site. In contrast to the binding assays, however, the Org compounds behaved as insurmountable antagonists of receptor function; in the reporter gene assay, the guanosine 5'-O-(3-[35S]thio)triphosphate binding assay and the mouse vas deferens assay they elicited a significant reduction in the Emax value for CB1 receptor agonists. The data presented clearly demonstrate, for the first time, that the cannabinoid CB1 receptor contains an allosteric binding site that can be recognized by synthetic small molecule ligands.

Obstetric outcome in women with subfertility

BACKGROUND

It has been suggested that a history of subfertility is associated with increased obstetric and perinatal risks. It is unclear if the cause is inherent characteristics in the women or the fertility treatment.

OBJECTIVES

To compare the obstetric and perinatal risks of singleton pregnancies in women with a history of subfertility in comparison with the general population.

DESIGN

Population cohort.

SETTING

Aberdeen, Scotland.

POPULATION

Cases were women attending the Fertility Clinic between 1989 and 1999 who subsequently went on to have singleton pregnancies. Controls included the general population of women who delivered singletons over the same period.

METHODS

We performed a retrospective cohort study to investigate the obstetric outcome of singleton pregnancies in women with subfertility. The general population of women who delivered singletons over the same period served as controls.

MAIN OUTCOME MEASURES

Obstetric and perinatal complications in singleton pregnancies.

RESULTS

Maternity records were available for a total of 1437 subfertile women and 21,688 controls. Subfertile women were older [mean (SD) age: 31 (4.7) years vs 27 (5.4) years, P < 0.01] and more likely to be primiparous (70% vs 65%, P < 0.001). After adjusting for age and parity, subfertile women were at increased risk of pre-eclampsia (OR 1.9, 95% CI 1.5-2.5), placenta praevia (OR 3.9, 95% CI 2.2-7.0) and placental abruption (OR 1.8, 95% CI 1.1-3.0), and more likely to undergo induction of labour (OR 1.5, 95% CI 1.3-1.6), caesarean section (OR 2.1, 95% CI 1.8-2.4) and instrumental delivery (OR 2.2, 95% CI 1.8-2.6), and deliver low birthweight (OR 1.4, 95% CI 1.3-1.7) and preterm (OR 1.7, 95% CI 1.2-2.2) infants. There were no differences between treatment-related and treatment-independent pregnancies.

CONCLUSION

Subfertile women are at higher risk of obstetric complications, which persist after adjusting for age and parity.

Persistent cough in children and the overuse of medications

OBJECTIVE

Children referred for persistent cough were evaluated for the referring and final diagnosis, and the extent of the use of medications prior to referral and the side effects encountered.

METHODS

Data on children seen by respiratory paediatricians for persistent cough (> or =4 weeks) in a tertiary respiratory setting were collected prospectively over 12 months.

RESULTS

Of the 49 children, 61.2% were diagnosed with asthma at referral, with similar referral rates from general practitioners and paediatricians. Children with isolated cough were just as likely to have been diagnosed with asthma as children with cough and wheeze. Medication use (asthma, gastro-oesophageal reflux and antibiotics) prior to referral was high, asthma medications were most common, and of these 12.9% had significant steroid side effects. The most common abnormality found (46.9%) was a bronchoscopically defined airway lesion, and in 56.5% of these children, another diagnosis (aspiration, achalasia, gastro-oesophageal reflux) existed. No children had a sole final diagnosis of asthma and pre-referral medications were weaned in all children.

CONCLUSION

Over diagnosis of asthma and the overuse of asthma treatments with significant side effects is common in children with persistent cough referred to a tertiary respiratory clinic. Children with persistent cough deserve careful evaluation to minimize the use of unnecessary medications and, if medications are used, assessment of response to treatment is important.