FV-162 is a novel, orally bioavailable, irreversible proteasome inhibitor with improved pharmacokinetics displaying preclinical efficacy with continuous daily dosing

Approved proteasome inhibitors have advanced the treatment of multiple myeloma but are associated with serious toxicities, poor pharmacokinetics, and most with the inconvenience of intravenous administration. We therefore sought to identify novel orally bioavailable proteasome inhibitors with a continuous daily dosing schedule and improved therapeutic window using a unique drug discovery platform. We employed a fluorine-based medicinal chemistry technology to synthesize 14 novel analogs of epoxyketone-based proteasome inhibitors and screened them for their stability, ability to inhibit the chymotrypsin-like proteasome, and antimyeloma activity in vitro. The tolerability, pharmacokinetics, pharmacodynamic activity, and antimyeloma efficacy of our lead candidate were examined in NOD/SCID mice. We identified a tripeptide epoxyketone, FV-162, as a metabolically stable, potent proteasome inhibitor cytotoxic to human myeloma cell lines and primary myeloma cells. FV-162 had limited toxicity and was well tolerated on a continuous daily dosing schedule. Compared with the benchmark oral irreversible proteasome inhibitor, ONX-0192, FV-162 had a lower peak plasma concentration and longer half-life, resulting in a larger area under the curve (AUC). Oral FV-162 treatment induced rapid, irreversible inhibition of chymotrypsin-like proteasome activity in murine red blood cells and inhibited tumor growth in a myeloma xenograft model. Our data suggest that oral FV-162 with continuous daily dosing schedule displays a favorable safety, efficacy, and pharmacokinetic profile in vivo, identifying it as a promising lead for clinical evaluation in myeloma therapy.

Characteristics and Outcomes of Older Patients Attending an Acute Medical Assessment Unit

The care of older persons accounts for an increasing proportion of the unscheduled care workload for acute hospitals. The recent development of acute medical assessment units (AMAU) has provided an alternative model for acute unscheduled care for all medical patients. Screening instruments have been developed to capture the higher levels of clinical complexity and medical comorbidities that older patients present with. The aim of this study was to report on the characteristics and outcomes for older patients reviewed in the AMAU of a tertiary referral university teaching hospital. Data on 3071 patients attending the unit over one year was prospectively collected and information on characteristics and outcomes for older patients retrieved. Older patients represented over one third (1066/3071, 35%) of those attending AMAU, and had an admission rate of nearly twice that of younger patients (60.5% vs 32%), highlighting the increased complexity of this group. Gerontologically attuned AMAUs have great potential to enhance care for frail older patients from the time of their acute presentation to hospital.

Increased thrombin generation potential in symptomatic versus asymptomatic moderate or severe carotid stenosis and relationship with cerebral microemboli

INTRODUCTION

The importance of thrombin generation in the pathogenesis of TIA or stroke and its relationship with cerebral microembolic signals (MES) in asymptomatic and symptomatic carotid stenosis has not been comprehensively assessed.

METHODS

Plasma thrombin generation parameters from patients with moderate or severe (≥ 50%) asymptomatic carotid stenosis were compared with those from patients with symptomatic carotid stenosis in the early (≤ 4 weeks) and late phases (≥ 3 months) after TIA or stroke in this prospective, pilot observational study. Thrombin generation profile was longitudinally assessed in symptomatic patients with data at each time point. Bilateral transcranial Doppler ultrasound monitoring of the middle cerebral arteries was performed whenever possible to classify patients as MES-positive or MES-negative.

RESULTS

Data from 31 asymptomatic, 46 'early symptomatic' and 35 'late symptomatic' patients were analysed. Peak thrombin (344.2 nM vs 305.3 nM; p = 0.01) and endogenous thrombin potential (1772.4 vs 1589.7; p = 0.047) were higher in early symptomatic than asymptomatic patients. Peak thrombin production decreased in symptomatic patients followed up from the early to late phase after TIA or stroke (339.7 nM vs 308.6 nM; p = 0.02). Transcranial Doppler ultrasound data were available in 25 asymptomatic, 31 early symptomatic and 27 late symptomatic patients. Early symptomatic MES-positive patients had a shorter 'time-to-peak thrombin' than asymptomatic MES-positive patients (p=0.04), suggesting a more procoagulant state in this early symptomatic subgroup.

DISCUSSION

Thrombin generation potential is greater in patients with recently symptomatic than asymptomatic carotid stenosis, and decreases over time following TIA or stroke associated with carotid stenosis. These data improve our understanding of the haemostatic/thrombotic biomarker profile in moderate-severe carotid stenosis.

Characteristics and outcomes of older persons attending the emergency department: a retrospective cohort study

BACKGROUND

The analysis of routinely collected hospital data informs the design of specialist services for at-risk older people.

AIM

Describe the outcomes of a cohort of older emergency department (ED) attendees and identify predictors of these outcomes.

DESIGN

retrospective cohort study.

METHODS

All patients aged 65 years or older attending an urban university hospital ED in January 2012 were included (N = 550). Outcomes were retrospectively followed for 12 months. Statistical analyses were based on multivariate binary logistic regression models and classification trees.

RESULTS

Of N = 550, 40.5% spent ≤6 h in the ED, but the proportion was 22.4% among those older than 81 years and not presenting with musculoskeletal problems/fractures. N = 349 (63.5%) were admitted from the ED. A significant multivariate predictor of in-hospital mortality was Charlson comorbidity index [CCI; odds ratio = 1.19, 95% confidence interval: 1.07, 1.34, P = 0.002]. Among patients who were discharged from ED without admission or after their first in-patient admission (N = 499), 232 (46.5%) re-attended ED within 1 year, with CCI being the best predictor of re-attendance (CCI ≤ 4: 25.8%, CCI > 5: 60.4%). Among N = 499, 34 (6.8%) had died after 1 year of initial ED presentation. The subgroup (N = 114) with the highest mortality (17.5%) was composed by those aged >77 years and brought in by ambulance on initial presentation.

CONCLUSIONS

Advanced age and comorbidity are important drivers of outcomes among older ED attendees. There is a need to embed specialist geriatric services within frontline services to make them more gerontologically attuned. Our results predate the opening of an acute medical unit with specialist geriatric input.

Longitudinal assessment of von Willebrand factor antigen and von Willebrand factor propeptide in response to alteration of antiplatelet therapy after TIA or ischaemic stroke

The impact of commencing or changing antiplatelet therapy on von Willebrand factor antigen (VWF:Ag) and von Willebrand factor propeptide (VWF:Ag II) levels has not been comprehensively assessed following TIA or ischaemic stroke. In this pilot, longitudinal, observational analytical study, VWF:Ag and VWF:Ag II levels were simultaneously quantified in platelet poor plasma by ELISA in patients within 4 weeks of TIA or ischaemic stroke (baseline), and then 14 days (14d) and >90 days (90d) after altering antiplatelet therapy. Ninety-one patients were recruited. Eighteen were initially assessed on no antiplatelet therapy, and then after 14d (N = 17) and 90d (N = 8) on aspirin monotherapy; 21 patients were assessed on aspirin and after 14d and 90d on clopidogrel; 52 were assessed on aspirin monotherapy, and after 14d and 90d on aspirin and dipyridamole combination therapy. VWF:Ag, VWF:Ag II levels and VWF:Ag/VWF:Ag II ratio were unchanged at 14d and 90d in the overall study population (p ≥ 0.1). VWF:Ag and VWF:Ag II levels remained stable at 14d and 90d after commencing aspirin (p ≥ 0.054), and after changing from aspirin to clopidogrel (p ≥ 0.2). Following the addition of dipyridamole MR to aspirin, there was a significant reduction in VWF:Ag levels at 14d (p = 0.03) and 90d (p = 0.005), but not in VWF:Ag II levels (p ≥ 0.3). The addition of dipyridamole to aspirin led to a persistent reduction in VWF:Ag but not in VWF:Ag II levels, suggesting that dipyridamole may inhibit release of platelet-derived VWF:Ag following TIA or ischaemic stroke.

Increased endothelial activation in recently symptomatic versus asymptomatic carotid artery stenosis and in cerebral microembolic-signal-negative patient subgroups

BACKGROUND AND PURPOSE

von Willebrand factor propeptide (VWF:Ag II) is potentially a more sensitive marker of acute endothelial activation than von Willebrand factor antigen (VWF:Ag). These biomarkers have not been simultaneously assessed in asymptomatic versus symptomatic carotid stenosis patients. The relationship between endothelial activation and cerebral microembolic signals (MESs) detected on transcranial Doppler ultrasound is unknown.

METHODS

In this multicentre observational analytical study, plasma VWF:Ag and VWF:Ag II levels in patients with ≥50% asymptomatic carotid stenosis were compared with those from patients with ≥50% symptomatic carotid stenosis in the 'early' (≤4 weeks) and 'late' (≥3 months) phases after transient ischaemic attack or ischaemic stroke. Endothelial activation was also longitudinally assessed in symptomatic patients during follow-up. Transcranial Doppler ultrasound monitoring classified patients as MES-positive or MES-negative.

RESULTS

Data from 31 asymptomatic patients were compared with those from 46 early symptomatic and 35 late phase symptomatic carotid stenosis patients, 23 of whom had undergone carotid intervention. VWF:Ag II levels were higher in early (12.8 μg/ml; P < 0.001), late (10.6 μg/ml; P = 0.01) and late post-intervention (10.6 μg/ml; P = 0.038) symptomatic patients than asymptomatic patients (8.9 μg/ml). VWF:Ag levels decreased in symptomatic patients followed up from the early to late phase after symptom onset (P = 0.048). Early symptomatic MES-negative patients had higher VWF: Ag II levels (13.3 vs. 9.0 μg/ml; P < 0.001) than asymptomatic MES-negative patients.

CONCLUSIONS

Endothelial activation is enhanced in symptomatic versus asymptomatic carotid stenosis patients, in early symptomatic versus asymptomatic MES-negative patients, and decreases over time in symptomatic patients. VWF:Ag II levels are a more sensitive marker of endothelial activation than VWF:Ag levels in carotid stenosis. The potential value of endothelial biomarkers and concurrent cerebral MES detection at predicting stroke risk in carotid stenosis warrants further study.

Nursing home residents attending the emergency department: clinical characteristics and outcomes

Nursing home (NH) residents represent the frailest group of older people, and providing gerontologically attuned care that addresses these frailties is often a challenge within the emergency department (ED). This study sought to prospectively profile acutely unwell NH residents in order to clarify some of the challenges of providing emergency care to this group. Over an 18-week period, we prospectively reviewed all NH residents presenting to the ED of an urban university teaching hospital. Relevant data were retrieved by direct physician review (as part of a comprehensive geriatric assessment in the ED), collateral history from NH staff and primary carers, and review of electronic records. There were 155 ED visits by 116 NH residents. Their mean age was 80.3 (±9.6) years. High pre-morbid levels of dependency were reflected by a mean Barthel Index of 34.1 (±20) and almost two-thirds had a pre-existing diagnosis of dementia. One-third of visits were during 'normal' working hours. Patients were reviewed by their regular NH doctor pre-transfer for 36% of visits. Using accepted international criteria, over half of the visits were deemed 'potentially preventable'. Unwell NH residents have complex medical needs. The decision to refer these patients to the ED is often made by 'out of hours' general practitioners and their initial care in the ED is directed by physicians with limited experience in geriatric medicine. Most referrals to the ED are potentially preventable but this would require enhancements to the package of care available in NHs.

Increased platelet activation in early symptomatic vs. asymptomatic carotid stenosis and relationship with microembolic status: results from the Platelets and Carotid Stenosis Study

BACKGROUND

Cerebral microembolic signals (MES) may predict increased stroke risk in carotid stenosis. However, the relationship between platelet counts or platelet activation status and MES in symptomatic vs. asymptomatic carotid stenosis has not been comprehensively assessed.

SETTING

University teaching hospitals.

METHODS

This prospective, pilot observational study assessed platelet counts and platelet activation status, and the relationship between platelet activation and MES in asymptomatic vs. early (≤ 4 weeks after TIA/stroke) and late phase (≥ 3 months) symptomatic moderate or severe (≥ 50%) carotid stenosis patients. Full blood count measurements were performed, and whole blood flow cytometry was used to quantify platelet surface activation marker expression (CD62P and CD63) and circulating leucocyte-platelet complexes. Bilateral simultaneous transcranial Doppler ultrasound monitoring of the middle cerebral arteries was performed for 1 h to classify patients as MES positive or MES negative.

RESULTS

Data from 31 asymptomatic patients were compared with 46 symptomatic patients in the early phase, and 35 of these patients were followed up to the late phase after symptom onset. The median platelet count (211 vs. 200 × 10(9)  L(-1) ; P = 0.03) and the median percentage of lymphocyte-platelet complexes was higher in early symptomatic than asymptomatic patients (2.8 vs. 2.4%; P = 0.001). The percentage of lymphocyte-platelet complexes was higher in early symptomatic than in asymptomatic patients with ≥ 70% carotid stenosis (P = 0.0005) and symptomatic patients recruited within 7 days of symptom onset (P = 0.028). Complete TCD data were available in 25 asymptomatic, 31 early phase symptomatic and 27 late phase symptomatic patients. Twelve per cent of asymptomatic vs. 32% of early phase symptomatic (P = 0.02) and 19% of late phase symptomatic patients (P = 0.2) were MES positive. Early symptomatic MES-negative patients had a higher percentage of lymphocyte-platelet complexes than asymptomatic MES-negative patients (2.8 vs. 2.3%; P = 0.0085).

DISCUSSION

Recently, symptomatic carotid stenosis patients have had higher platelet counts (potentially reflecting increased platelet production, mobilization or reduced clearance) and platelet activation status than asymptomatic patients. MES were more frequently detected in early symptomatic than asymptomatic patients, but the differences between late symptomatic and asymptomatic groups were not significant. Increased lymphocyte-platelet complex formation in recently symptomatic vs. asymptomatic MES-negative patients indicates enhanced platelet activation in this early symptomatic subgroup. Platelet biomarkers, in combination with TCD, have the potential to aid risk-stratification in asymptomatic and symptomatic carotid stenosis patients.

Baltes' SOC model of successful ageing as a potential framework for stroke rehabilitation

AIM

The aim of this paper is to explore approaches used to address some stroke rehabilitation interventions and to examine the potential use of one of the life-span theories called the Baltes' model of selective optimisation with compensation (SOC) as a potential framework.

KEY FINDINGS AND IMPLICATIONS

Some of the key considerations for a stroke rehabilitation intervention framework are highlighted including accommodating for the life management changes post stroke, alterations in self-regulation, acknowledge losses and focusing on a person-centred approach for transition from acute rehabilitation to the home or community setting. The Baltes' SOC model is then described in terms of these considerations for a stroke rehabilitation intervention framework.

CONCLUSIONS AND RECOMMENDATIONS

The Baltes' SOC model may offer further insights, including ageing considerations, for stroke rehabilitation approaches and interventions. It has potential to facilitate some of the necessary complexities of adjustment required in stroke rehabilitation. However, further development in terms of empirical support is required for using the model as a framework to structure stroke rehabilitation intervention. Implications for Rehabilitation There is a scarcity of theoretical frameworks that can facilitate and be inclusive for all the necessary complexities of adjustment, required in stroke rehabilitation. In addition to motor recovery post stroke, rehabilitation intervention frameworks should be goal orientated; address self-regulatory processes; be person-centred and use a common language for goal planning, setting and attainment. The Baltes' SOC model is one such framework that may address some of the considerations for stroke rehabilitation, including motor recovery and other life management aspects.

Longitudinal assessment of thrombin generation potential in response to alteration of antiplatelet therapy after TIA or ischaemic stroke

The impact of changing antiplatelet therapy on thrombin generation potential in patients with ischaemic cerebrovascular disease (CVD) is unclear. We assessed patients within 4 weeks of TIA or ischaemic stroke (baseline), and then 14 days (14d) and >90 days (90d) after altering antiplatelet therapy. Thrombin generation was assessed in platelet poor plasma. Ninety-one patients were recruited. Twenty-four were initially assessed on no antiplatelet therapy, and then after 14d (N = 23) and 90d (N = 8) on aspirin monotherapy; 52 were assessed on aspirin monotherapy, and after 14 and 90 days on aspirin and dipyridamole combination therapy; 21 patients were assessed on aspirin and after 14 days (N = 21) and 90 days (N = 19) on clopidogrel. Peak thrombin generation and endogenous thrombin potential were reduced at 14 and 90 days (p ≤ 0.04) in the overall cohort. We assessed the impact of individual antiplatelet regimens on thrombin generation parameters to investigate the cause of this effect. Lag time and time-to-peak thrombin generation were unchanged at 14 days, but reduced 90 days after commencing aspirin (p ≤ 0.009). Lag time, peak thrombin generation and endogenous thrombin potential were reduced at both 14 and 90 days after adding dipyridamole to aspirin (p ≤ 0.01). Lag time was reduced 14 days after changing from aspirin to clopidogrel (p = 0.045), but this effect was not maintained at 90 days (p = 0.2). This pilot study did not show any consistent effects of commencing aspirin, or of changing from aspirin to clopidogrel on thrombin generation potential during follow-up. The addition of dipyridamole to aspirin led to a persistent reduction in peak and total thrombin generation ex vivo, and illustrates the diverse, potentially beneficial, newly recognised 'anti-coagulant' effects of dipyridamole in ischaemic CVD.

Effects of abdominal fat distribution parameters on severity of acute pancreatitis

BACKGROUND

Obesity is a well-established risk factor for acute pancreatitis. Increased visceral fat has been shown to exacerbate the pro-inflammatory milieu experienced by patients. This study aimed to investigate the relationship between the severity of acute pancreatitis and abdominal fat distribution parameters measured on computed tomography (CT) scan.

METHODS

Consecutive patients admitted to Cork University Hospital with acute pancreatitis between January 2005 and December 2010 were evaluated for inclusion in the study. An open source image analysis software (Osirix, v 3.9) was used to calculate individual abdominal fat distribution parameters from CT scans by segmentation of abdominal tissues.

RESULTS

A total of 214 patients were admitted with pancreatitis between January 2005 and December 2010. Sixty-two of these patients underwent a CT scan and were thus eligible for inclusion. Visceral fat volume was the volumetric fat parameter that had the most significant association with severe acute pancreatitis (P = 0.003). There was a significant association between visceral fat volume and subsequent development of systemic complications of severe acute pancreatitis (P = 0.003). There was a strong association between mortality and visceral fat volume (P = 0.019). Multivariate regression analysis, adjusted for gender, did not identify any individual abdominal fat distribution index as an independent risk factor for severe acute pancreatitis.

CONCLUSIONS

Overall, estimation of abdominal fat distribution parameters from CT scans performed on patients with acute pancreatitis indicates a strong association between visceral fat, severe acute pancreatitis, and the subsequent development of systemic complications. These data suggest that visceral fat volume should be incorporated into future predictive scoring systems.

Ageism and clinical research

Despite being the most significant consumers of health care resources and medications worldwide, recent international research has highlighted the under-representation of older participants from clinical trials. This creates problems for physicians as the patients seen in clinical practice are not representative of those on which medical treatments and interventions have been trialled, and we need to consider whether results (both negative and positive) from these trials are applicable to these patients. Our aim was to gauge whether exclusion of older people was prevalent in research proposals submitted to Dublin teaching hospitals. We audited all clinical research proposals submitted to the Research Ethics committee (REC) covering the teaching hospitals attached to Trinity College Dublin (TCD) from July 2008 to July 2011 inclusive, recording exclusion of patients based on an arbitrary upper age limit. Of the 226 relevant trials studied, 31(13.7%) excluded participants based solely on an arbitrary upper age limit. 22 (9.8%) of the relevant trials were submitted by geriatricians, none of which excluded patients based solely on age. Over 50% (12 of 22) trials submitted by neurology/psychiatry excluded patients based on an upper age limit. The mean upper age limit used over all trials as a cut-off was 69.2 years of age. As well as this, the majority of the remaining trials also contained other exclusion criteria, especially those based on cognitive function which further limited participation of older people. While we found that a significant proportion of clinical trials submitted to the TCD REC still excluded patients based arbitrarily on an upper age limit, participation rates of older people seem to be higher in this Irish centre than that seen in international trials. Significant room for improvement still remains however and there needs to be a promotion of greater awareness of the need for developing, testing and licensing medicines so that it mirrors the consumer groups in which they will be used. Increased input from geriatricians around the testing and licensing of medicines, and in licensing agencies, would greatly help in this regard. It is both unhelpful for optimal healthcare as well as fundamentally unjust to exclude participants from clinical research based solely on an arbitrary age limit.

Subjective memory complaints in community dwelling healthy older people: the influence of brain and psychopathology

OBJECTIVES

Subjective memory complaints (SMC) are common. We aimed to characterize the relationship between psychiatric illness and white matter disease to SMC in a sample of healthy older people.

MEASUREMENTS

Cognitively normal subjects between 55 and 90 years had age-adjusted and education-adjusted Consortium to Establish a Registry for Alzheimer's disease (CERAD) scores ≤1.5 SD from standard mean. ApoE genotyping was performed using polymerase chain reaction. Sixty subjects (30 SMC, 30 controls) underwent 3T MRI, which was rated by two raters blinded to the diagnosis, for periventricular (PVH) and deep white matter hyperintensities (DWMH) using the Fazekas scale. Subjective memory was assessed by asking the participant, Do you feel like your memory or thinking is becoming worse?

RESULTS

Two hundred and fifteen volunteers were assessed. Ninety-six were cognitively normal (mean age 62.5 years). SMC were reported by 52/96 subjects (54%). These were compared with subjects who denied SMC. Participants with a history of depression or anxiety were more likely to have SMC (p = 0.02). The frequency distribution of ApoE4 allele and CERAD scores were similar. White matter load was similar (p ≤ 0.47), with a high prevalence of PVH and DWMH seen (100% and 88% of scans, respectively).

CONCLUSION

Both SMC and white matter disease were common. SMC were associated with a history of depression or anxiety but not with white matter disease. Evaluation for a history of depression and anxiety in people with SMC is supported by these findings.

Adaptation to stroke using a model of successful aging

The process of adaptation to the physical and psychosocial consequences after stroke is a major challenge for many individuals affected. The aim of this study was to examine if stroke patients within 1 month of admission (n = 153) and followed up at 1 year (n = 107) engage in selection, optimization, and compensation (SOC) adaptive strategies and the relationship of these strategies with functional ability, health-related quality of life (HRQOL) and depression 1 year later. Adaptive strategies were measured using a 15-item SOC questionnaire. Internal and external resources were assessed including recovery locus of control, stroke severity, and socio-demographics. Outcome measures were the Stroke Specific Quality of Life Questionnaire (SS-QoL), the Nottingham Extended Activities of Daily Living Scale and the Depression Subscale of the Hospital Anxiety and Depression Scale. Findings indicated that stroke patients engaged in the use of SOC strategies but the use of these strategies were not predictive of HRQOL, functional ability or depression 1 year after stroke. The use of SOC strategies were not age specific and were consistent over time, with the exception of the compensation subscale. Results indicate that SOC strategies may potentially be used in response to loss regulation after stroke and that an individual's initial HRQOL functional ability, levels of depression and socio-economic status that are important factors in determining outcome 1 year after stroke. A stroke-specific measure of SOC may be warranted in order to detect significant differences in determining outcomes for a stroke population.