Preclinical trials in autosomal dominant AD: implementation of the DIAN-TU trial

The Dominantly Inherited Alzheimer's Network Trials Unit (DIAN-TU) was formed to direct the design and management of interventional therapeutic trials of international DIAN and autosomal dominant Alzheimer's disease (ADAD) participants. The goal of the DIAN-TU is to implement safe trials that have the highest likelihood of success while advancing scientific understanding of these diseases and clinical effects of proposed therapies. The DIAN-TU has launched a trial design that leverages the existing infrastructure of the ongoing DIAN observational study, takes advantage of a variety of drug targets, incorporates the latest results of biomarker and cognitive data collected during the observational study, and implements biomarkers measuring Alzheimer's disease (AD) biological processes to improve the efficiency of trial design. The DIAN-TU trial design is unique due to the sophisticated design of multiple drugs, multiple pharmaceutical partners, academics servings as sponsor, geographic distribution of a rare population and intensive safety and biomarker assessments. The implementation of the operational aspects such as home health research delivery, safety magnetic resonance imagings (MRIs) at remote locations, monitoring clinical and cognitive measures, and regulatory management involving multiple pharmaceutical sponsors of the complex DIAN-TU trial are described.

The roles of cell surface attachment molecules and coagulation Factor X in adenovirus 5-mediated gene transfer in pancreatic cancer cells

Transduction of 11 pancreatic cancer cell lines with a replication-deficient adenovirus 5 expressing enhanced green fluorescent protein (Ad5EGFP) was analyzed and variable EGFP levels were observed, ranging from <1% to ∼40% of cells transduced, depending on the cell line. Efficient Ad5EGFP transduction was associated mainly with higher levels of cell surface Coxsackie and adenovirus receptor (CAR) but not with expression of α(v)β(3) and α(v)β(5) integrins and was fiber dependent. Reduction of CAR by RNA interference resulted in a corresponding decrease in Ad5EGFP transduction. Pre-treatment of Ad5EGFP with blood coagulation Factor X increased virus entry even in the presence of low CAR levels generated by RNA interference, suggesting a potential alternative route of Ad5 entry into pancreatic cancer cells. Immunohistochemistry carried out on 188 pancreatic ductal adenocarcinomas and 68 matched controls showed that CAR was absent in 102 (54%) of adenocarcinomas, whereas moderate and strong staining was observed in 58 (31%) and 28 (15%) cases, respectively. Weak or absent CAR immunolabeling correlated with poor histological differentiation of pancreatic cancer. In normal tissue, strong immunolabeling was detected in islet cells and in the majority of inter- and intralobular pancreatic ducts.

Phase Ib study of mapatumumab in combination with sorafenib in patients with advanced hepatocellular carcinoma (HCC) and chronic viral hepatitis

261

Background: Mapatumumab is a fully human agonist monoclonal antibody to the tumor necrosis factor-related apoptosis-inducing ligand receptor 1 (TRAIL-R1). Sorafenib targets Mcl-1, a key TRAIL resistance protein, and accordingly could enhance mapatumumab's pro-apoptotic activity. Based on this and on preclinical data on mapatumumab in HCC cell lines, the current dose-escalation study is evaluating mapatumumab in combination with sorafenib in patients with advanced HCC.

Methods: Eligible patients had advanced HCC, Child-Pugh A or Model for End-Stage Liver Disease score < 15, and were positive for hepatitis B surface antigen or hepatitis C antibody. Intravenous mapatumumab was administered at 3, 10 or 30 mg/kg every 21 days with sorafenib (400 mg twice daily) until disease progression or unacceptable toxicity. Dose-limiting toxicities (DLTs) included events considered at least possibly related to mapatumumab and/or its interaction with sorafenib. Tumor measurements were performed every 2 cycles. Dose escalation required at least 3 patients in a cohort to receive >= 50% of full-dose sorafenib in the first 2 cycles.

Results: To date, 19 patients have been enrolled in the 3 mg/kg (n=6), 10 mg/kg (n=9) and 30 mg/kg (n=4) cohorts and have received a median of 4 cycles (range 1 to 24 cycles); 4 patients have received >= 11 cycles. The maximum tolerated dose has not been reached. DLTs that prompted expansion of the 3 mg/kg and 10 mg/kg cohorts were elevations of amylase and/or lipase (1 at 3 mg/kg, 1 at 10 mg/kg). Other Grade 3-4 events considered at least possibly related to mapatumumab and/or its interaction with sorafenib included hepatic pain (1/17), thrombocytopenia (1/17), increased aspartate aminotransferase (1/17), increased lipase (1/17), and increased gamma-glutamyltransferase (1/17). Two patients have had a partial response and 4 patients have had stable disease lasting > 12 weeks, based on investigator assessment.

Conclusions: Mapatumumab was well-tolerated at doses up to 30 mg/kg in combination with sorafenib in patients with HCC and viral hepatitis. A randomized phase II study of this combination in patients with advanced HCC is planned.

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A randomized phase II trial of mapatumumab, a TRAIL-R1 agonist monoclonal antibody, in combination with carboplatin and paclitaxel in patients with advanced NSCLC

LBA7501

Background: Mapatumumab, a fully human agonist monoclonal antibody, targets and activates the death receptor TRAIL-R1. We conducted this randomized, controlled phase II trial to evaluate mapatumumab in combination with carboplatin and paclitaxel as first-line therapy in advanced non-small call lung cancer (NSCLC).

Methods: Patients were required to have histologically or cytologically confirmed Stage IIIB or IV advanced primary NSCLC with measurable disease by RECIST. Patients were randomly assigned to Arm A, paclitaxel 200 mg/m2 + carboplatin AUC 6.0 (PC); Arm B, PC + mapatumumab 10 mg/kg; or Arm C, PC + mapatumumab 30 mg/kg. Cycles were repeated every 21 days; patients completed up to 6 cycles in the absence of evidence of disease progression or unacceptable toxicity. Patients in Arms B and C could receive additional cycles of mapatumumab in the absence of disease progression. The co-primary endpoints were response rate (RR; complete response + partial response) and progression-free survival (PFS). Images were read by independent radiologists blinded to treatment group assignment, as well as locally.

Results: 111 patients were enrolled at 22 sites in 4 countries. Addition of mapatumumab to PC did not improve RR or PFS. RR and PFS, based on the independent read, and overall survival results are summarized below. The results based on local reading also showed no benefit from the addition of mapatumumab to PC. Adverse events were generally balanced across treatment groups; there was no evidence that mapatumumab exacerbated toxicities associated with PC.

Conclusions: The results do not support further evaluation of mapatumumab in combination with PC in patients with advanced NSCLC. Additional trials of mapatumumab in other indications are ongoing.

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Using the Lomb periodogram for non-contact estimation of respiration rates

We describe a contact-less method for measurement of respiration rate during sleep using a 5.8GHz radio-frequency bio-motion sensor. The sensor operates by sensing phase shifts in reflected radio waves from the torso caused by respiratory movements and other bodily movements such as twitches, positional changes etc. These non-respiratory motion artefacts can obscure reliable estimation of breathinig rates if conventional spectral analysis is used. This paper reports on the accuracy of the respiration rate estimates obtained via algorithmic approaches using Lomb-periodogram based analysis (which can deal with missing or corrupted data), as compared to conventional spectral analysis. Gold-standard respiration rates are derived by expert scoring of respiration rates measured through polysomnography (PSG) from sensors (Respiratory Inductance Plethysmography (RIP) belts) in contact with the subject in an accredited sleep laboratory. Specifically, respiration rates for 15-minute segments chosen from 10 subjects free of Sleep-Disorded Breathing (AHI〈5) were selected for analysis in this paper. Comparison to the expert annotation indicates strong agreement, with the Lomb-periodogram respiration rates with the average error between the measurements being less than 0.4 breaths/min and a standard deviation of 0.3 breaths/minute. Moreover, we showed that the proposed algorithm could track respiration rate over the complete night's recordings for those 10 subjects. We conclude that the non-contact biomotion sensor may provide a promising approach to continuous respiration rate monitoring of reasonable accuracy.

Detection of cardiac activity using a 5.8 GHz radio frequency sensor

A 5.8-GHz ISM-Band radio-frequency sensor has been developed for non-contact measurement of respiration and heart rate from stationary and semi-stationary subjects at a distance of 0.5 to 1.5 meters. We report on the accuracy of the heart rate measurements obtained using two algorithmic approaches, as compared to a reference heart rate obtained using a pulse oximeter. Simultaneous Photoplethysmograph (PPG) and non-contact sensor recordings were recorded over fifteen minute periods for ten healthy subjects (8M/2F, ages 29.6 + or - 5.6 yrs) One algorithm is based on automated detection of individual peaks associated with each cardiac cycle; a second algorithm extracts a heart rate over a 60-second period using spectral analysis. Peaks were also extracted manually for comparison with the automated method. The peak-detection methods were less accurate than the spectral methods, but suggest the possibility of acquiring beat by beat data; the spectral algorithms measured heart rate to within + or -10% for the ten subjects chosen. Non-contact measurement of heart rate will be useful in chronic disease monitoring for conditions such as heart failure and cardiovascular disease.

Microglial activation and amyloid deposition in mild cognitive impairment: a PET study

BACKGROUND

Activated microglia may play a role in the pathogenesis of Alzheimer disease (AD) as they cluster around beta-amyloid (Abeta) plaques. They are, therefore, a potential therapeutic target in both AD and its prodrome amnestic mild cognitive impairment (MCI).

OBJECTIVE

To characterize in vivo with (11)C-(R)-PK11195 and (11)C-PIB PET the distribution of microglial activation and amyloid deposition in patients with amnestic MCI.

METHODS

Fourteen subjects with MCI had (11)C-(R)-PK11195 and (11)C-PIB PET with psychometric tests.

RESULTS

Seven out of 14 (50%) patients with MCI had increased cortical (11)C-PIB retention (p < 0.001) while 5 out of 13 (38%) subjects with MCI showed increased (11)C-(R)-PK11195 uptake. The MCI subgroup with increased (11)C-PIB retention also showed increased cortical (11)C-(R)-PK11195 binding (p < 0.036) though this increase only remained significant in frontal cortex after a correction for multiple comparisons. There was no correlation between regional levels of (11)C-(R)-PK11195 and (11)C-PIB binding in individual patients with MCI: only three of the five MCI cases with increased (11)C-(R)-PK11195 binding had increased levels of (11)C-PIB retention.

CONCLUSIONS

Our findings indicate that, while amyloid deposition and microglial activation can be detected in vivo in around 50% of patients with mild cognitive impairment (MCI), these pathologies can occur independently. The detection of microglial activation in patients with MCI suggests that anti-inflammatory therapies may be relevant to the prevention of AD.

Mitogen-induced responses in lymphocytes from platypus, the Tasmanian devil and the eastern barred bandicoot

OBJECTIVE

As the platypus (Ornithorhynchus anatinus), the Tasmanian devil (Sarcophilus harrisi) and the eastern barred bandicoot (Perameles gunni) are currently at risk of serious population decline or extinction from fatal diseases in Tasmania, the goal of the present study was to describe the normal immune response of these species to challenge using the lymphocyte proliferation assay, to give a solid basis for further studies.

METHODS

For this preliminary study, we performed lymphocyte proliferation assays on peripheral blood mononuclear cells (PBMC) from the three species. We used the common mitogens phytohaemagglutinin (PHA), concanavalin A (ConA), lipopolysaccharide (LPS) and pokeweed mitogen (PWM).

RESULTS

All three species recorded the highest stimulation index (SI) with the T-cell mitogens PHA and ConA. Tasmanian devils and bandicoots had greater responses than platypuses, although variability between individual animals was high.

CONCLUSION

For the first time, we report the normal cellular response of the platypus, the Tasmanian devil and the eastern barred bandicoot to a range of commonly used mitogens.

Amnestic mild cognitive impairment: structural MR imaging findings predictive of conversion to Alzheimer disease

BACKGROUND AND PURPOSE

Mild cognitive impairment (MCI) is considered by many to be a prodromal phase of Alzheimer disease (AD). We used voxel-based morphometry (VBM) to find out whether structural differences on MR imaging could offer insight into the development of clinical AD in patients with amnestic MCI at 3-year follow-up.

MATERIALS AND METHODS

Twenty-four amnestic patients with MCI were included. After 3 years, 46% had progressed to AD (n = 11; age, 72.7 +/- 4.8 years; women/men, 8/3). For 13 patients (age, 72.4 +/- 8.6 years; women/men, 10/3), the diagnosis remained MCI. Baseline MR imaging at 1.5T included a coronal heavily T1-weighted 3D gradient-echo sequence. Localized gray matter differences were assessed with VBM.

RESULTS

The converters had less gray matter volume in medial (including the hippocampus) and lateral temporal lobe, parietal lobe, and lateral temporal lobe structures. After correction for age, sex, total gray matter volume, and neuropsychological evaluation, left-sided atrophy remained statistically significant. Specifically, converters had more left parietal atrophy (angular gyrus and inferior parietal lobule) and left lateral temporal lobe atrophy (superior and middle temporal gyrus) than stable patients with MCI.

CONCLUSION

By studying 2 MCI populations, converters versus nonconverters, we found atrophy beyond the medial temporal lobe to be characteristic of patients with MCI who will progress to dementia. Atrophy of structures such as the left lateral temporal lobe and left parietal cortex may independently predict conversion.

Risk and severity of motor vehicle crashes in patients with obstructive sleep apnoea/hypopnoea

BACKGROUND

Obstructive sleep apnoea/hypopnoea (OSAH) appears to be associated with an increased risk of motor vehicle crashes (MVCs). However, its impact on crash patterns, particularly the severity of crashes, has not been well described. A study was undertaken to determine whether OSAH severity influenced crash severity in patients referred for investigation of suspected sleep-disordered breathing.

METHODS

Objective crash data (including the nature of crashes) for 783 patients with suspected OSAH for the 3 years prior to polysomnography were obtained from provincial insurance records and compared with data for 783 age- and sex-matched controls. The patient group was 71% male with a mean age of 50 years, a mean apnoea-hypopnoea index (AHI) of 22 events/h and a mean Epworth Sleepiness Scale score of 10.

RESULTS

There were 375 crashes in the 3-year period, 252 in patients and 123 in controls. Compared with controls, patients with mild, moderate and severe OSAH had an increased rate of MVCs with relative risks of 2.6 (95% CI 1.7 to 3.9), 1.9 (95% CI 1.2 to 2.8) and 2.0 (95% CI 1.4 to 3.0), respectively. Patients with suspected OSAH and normal polysomnography (AHI 0-5) did not have an increased rate of MVC (relative risk 1.5 (95% CI 0.9 to 2.5), p = 0.21). When the impact of OSAH on MVC associated with personal injury was examined, patients with mild, moderate and severe OSAH had a substantially higher rate of MVCs than controls with relative risks of 4.8 (95% CI 1.8 to 12.4), 3.0 (95% CI 1.3 to 7.0) and 4.3 (95% CI 1.8 to 8.9), respectively, whereas patients without OSAH had similar crash rates to controls with a relative risk of 0.6 (95% CI 0.2 to 2.5). Very severe MVCs (head-on collisions or those involving pedestrians or cyclists) were rare, but 80% of these occurred in patients with OSAH (p = 0.06).

CONCLUSION

Patients with OSAH have increased rates of MVCs, and disproportionately increased rates of MVCs are associated with personal injury.

The impact of obstructive sleep apnea and daytime sleepiness on work limitation

BACKGROUND

Many patients with obstructive sleep apnea (OSA) participate in the work force. However, the impact of OSA and sleepiness on work performance is unclear.

METHODS

To address this issue, we administered the Epworth Sleepiness Scale (ESS), the Work Limitations Questionnaire (WLQ), and an occupational survey to patients undergoing full-night polysomnography for the investigation of sleep-disordered breathing. Of 498 patients enrolled in the study, 428 (86.0%) completed the questionnaires. Their mean age+/-standard deviation (SD) was 49+/-12 years, mean body mass index (BMI) was 31+/-7 kg/m(2) mean apnea hypopnea index (AHI) was 21+/-22 events/h, and mean ESS score was 10+/-5. Subjects worked a mean of 39+/-18 h per week. The first 100 patients to complete the survey were followed up at two years.

RESULTS

In the group as a whole, there was no significant relationship between severity of OSA and the four dimensions of work limitation. However, in blue-collar workers, significant differences were detected between patients with mild OSA (AHI 5-15/h) and those with severe OSA (AHI>30/h) with respect to time management (limited 23.1% of the time vs. 43.8%, p=0.05) and mental/personnel interactions (17.9% vs. 33.0%, p=0.05). In contrast, there were strong associations between subjective sleepiness (as assessed by the ESS) and three of the four scales of work limitation. That is, patients with an ESS of 5 had much less work limitation compared to those with an ESS 18 in terms of time management (19.7% vs. 38.6 %, p<0.001), mental-interpersonal relationships (15.5% vs. 36.0%, p<0.001) and work output (16.8% vs. 36.0%; p<0.001). Of the group followed up, 49 returned surveys and 33 who were using continuous positive airway pressure (CPAP) showed significant improvements between the initial and second follow-up in time management (26% vs. 9%, p=0.0005), mental-interpersonal relationships (16% vs. 11.0%, p=0.014) and work output (18% vs. 10%; p<0.009).

CONCLUSION

We have demonstrated a clear relationship between excessive sleepiness and decreased work productivity in a population referred for suspected sleep-disordered breathing. Screening for sleepiness and sleep-disordered breathing in the workplace has the potential to identify a reversible cause of low work productivity.

A Systematic Review and Meta-Analysis of CSF Neurofilament Protein Levels as Biomarkers in Dementia

BACKGROUND

Loss of cortical neurons is a key pathological feature in neurodegenerative dementias. Cerebrospinal fluid (CSF) neurofilaments (Nf) are a biomarker for neuronal death and axonal loss.

OBJECTIVE

To perform a meta-analysis to investigate the value of CSF Nf levels for the laboratory-supported differential diagnosis of neurodegenerative dementias.

METHODS

A systematic review and meta-analysis of studies on CSF Nf heavy (NfH) and light (NfL) levels in patients with dementia. The dementia subgroups analysed were Alzheimer (AD), frontotemporal lobe dementia (FTLD), vascular dementia (SVD), minimal cognitive deficit (MCI).

RESULTS

We identified 12 studies on CSF NfH and NfL levels which met the inclusion criteria and 11 were of a quality good enough to be used in this meta-analysis. CSF data was available on 818 patients (306 AD, 106 SVD, 98 FTLD, 25 MCI, 283 controls). Overall CSF NfH and NfL levels were higher in patients with AD, FTLD and SVD when compared to controls. The size of the effect ranged from 0.71 to 1.38. The strongest effect was observed for the comparison of FTLD patients with controls, both for NfL (1.38) and NfH (0.74). CSF NfL were also able to separate patients with FTLD from those with AD.

CONCLUSION

At present we cannot recommend CSF NfH and NfL levels for use as a screening test in the diagnosis of dementia because of the rather small effect size. However, both neurofilament proteins may be of value for targeted investigation of some patients with FTLD, SVD and AD.

Amyloid, hypometabolism, and cognition in Alzheimer disease: an [11C]PIB and [18F]FDG PET study

OBJECTIVE

To investigate the association between brain amyloid load in Alzheimer disease (AD) measured by [11C]PIB-PET, regional cerebral glucose metabolism (rCMRGlc) measured by [18F]FDG-PET, and cognition.

METHODS

Nineteen subjects with AD and 14 controls had [11C]PIB-PET and underwent a battery of psychometric tests. Twelve of those subjects with AD and eight controls had [18F]FDG-PET. Parametric images of [11C]PIB binding and rCMRGlc were interrogated with a region-of-interest atlas and statistical parametric mapping. [11C]PIB binding and rCMRGlc were correlated with scores on psychometric tests.

RESULTS

AD subjects showed twofold increases in mean [11C]PIB binding in cingulate, frontal, temporal, parietal, and occipital cortical areas. Higher cortical amyloid load correlated with lower scores on facial and word recognition tests. Two patients fulfilling the clinical criteria for AD had normal [11C]PIB at baseline. Over 20 months this remained normal in one but increased in the cingulate of the other. Mean levels of temporal and parietal rCMRGlc were reduced by 20% in AD and these correlated with mini mental scores, immediate recall, and recognition memory test for words. Higher [11C]PIB uptake correlated with lower rCMRGlc in temporal and parietal cortices.

CONCLUSION

[11C]PIB-PET detected an increased amyloid plaque load in 89% of patients with clinically probable Alzheimer disease (AD). The high frontal amyloid load detected by [11C]PIB-PET in AD in the face of spared glucose metabolism is of interest and suggests that amyloid plaque formation may not be directly responsible for neuronal dysfunction in this disorder.

HGS-ETR2—A fully human monoclonal antibody to TRAIL-R2: Results of a phase I trial in patients with advanced solid tumors

3012

Background: HGS-ETR2 is a fully-human high-affinity monoclonal antibody that is agonistic to the Tumor Necrosis Factor-Related Apoptosis-Inducing Ligand Receptor 2 (TRAIL-R2, DR5). TRAIL-R2 is expressed more widely on the surface of tumor cells than normal cells; binding of HGS-ETR2 to TRAIL-R2 leads to activation of the extrinsic apoptosis pathway. HGS-ETR2 shows anti-tumor activity at doses ≥ 0.3 mg/kg in xenograft models, both as a single agent and in combination with chemotherapeutic agents. Methods: This phase 1, dose-escalation study assessed the safety, tolerability, pharmacokinetics and immunogenicity of HGS-ETR2 administered IV every 14 days in patients with advanced solid tumors. Patients received HGS-ETR2 until disease progression or unacceptable toxicity. Tumor measurements were repeated every 2 months. Results: To date, 31 patients have received 167 courses of HGS-ETR2 over 5 dose levels: 0.1, 0.3, 1.0, 3.0 and 10.0 mg/kg q14 days. The majority (26 of 31) received at least 4 courses. One patient experienced a dose-limiting toxicity of grade 3 hyperamylasemia at the 10 mg/kg dose level. The event was determined to be possibly related to HGS-ETR2 and also possibly related to a nutritional supplement. Stable disease was achieved in 10 patients for 4 to 16 cycles. One patient with chemotherapy-refractive Hodgkin’s disease had a tumor regression of abdominal disease. HGS-ETR2 pharmacokinetics were linear up to 10 mg/kg. At the 10 mg/kg dose, the pharmacokinetics were characterized by a mean (SD) t1/2β of 11 (4) days, CL of 6.0 (0.7) mL/day, and V1 of 47 (8) mL/kg, slightly larger than the plasma volume. The 1.8-fold larger Vss of 85 (27) mL/kg indicates that HGS-ETR2 distributes outside the plasma compartment. Human anti-human antibody formation has not been detected. Conclusions: HGS-ETR2 can be safely administered every 14 days at doses up to and including 10 mg/kg. Further evaluation of HGS-ETR2 is planned, including studies of HGS-ETR2 in combination with chemotherapeutic agents.

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