Trial of Solanezumab for Mild Dementia Due to Alzheimer's Disease.

BACKGROUND: Alzheimer's disease is characterized by amyloid-beta (Aß) plaques and neurofibrillary tangles. The humanized monoclonal antibody solanezumab was designed to increase the clearance from the brain of soluble Aß, peptides that may lead to toxic effects in the synapses and precede the deposition of fibrillary amyloid. METHODS: We conducted a double-blind, placebo-controlled, phase 3 trial involving patients with mild dementia due to Alzheimer's disease, defined as a Mini-Mental State Examination (MMSE) score of 20 to 26 (on a scale from 0 to 30, with higher scores indicating better cognition) and with amyloid deposition shown by means of florbetapir positron-emission tomography or Aß1-42 measurements in cerebrospinal fluid. Patients were randomly assigned to receive solanezumab at a dose of 400 mg or placebo intravenously every 4 weeks for 76 weeks. The primary outcome was the change from baseline to week 80 in the score on the 14-item cognitive subscale of the Alzheimer's Disease Assessment Scale (ADAS-cog14; scores range from 0 to 90, with higher scores indicating greater cognitive impairment). RESULTS: A total of 2129 patients were enrolled, of whom 1057 were assigned to receive solanezumab and 1072 to receive placebo. The mean change from baseline in the ADAS-cog14 score was 6.65 in the solanezumab group and 7.44 in the placebo group, with no significant between-group difference at week 80 (difference, -0.80; 95% confidence interval, -1.73 to 0.14; P=0.10). As a result of the failure to reach significance with regard to the primary outcome in the prespecified hierarchical analysis, the secondary outcomes were considered to be descriptive and are reported without significance testing. The change from baseline in the MMSE score was -3.17 in the solanezumab group and -3.66 in the placebo group. Adverse cerebral edema or effusion lesions that were observed on magnetic resonance imaging after randomization occurred in 1 patient in the solanezumab group and in 2 in the placebo group. CONCLUSIONS: Solanezumab at a dose of 400 mg administered every 4 weeks in patients with mild Alzheimer's disease did not significantly affect cognitive decline. (Funded by Eli Lilly; EXPEDITION3 ClinicalTrials.gov number, NCT01900665 .).

Adaptation of the robust method to large distributions of reference values: program modifications and comparison of alternative computational methods.

The objective of this research was to compute reference limits using reference values from patients entering pharmaceutical development clinical trials by the nonparametric method and the robust method of Horn and Pesce, with and without outlier exclusion, and compare the methods with respect to influence on the limits. Reference limits were computed for 38 analytes with over 130,000 subjects contributing reference values. Subjects were partitioned into 10 demographic strata for limit computation. Limits were computed for both 95- and 98-percentile reference intervals by both methods. For each reference interval and method, the limits were calculated with and without outliers. Outliers were excluded by the Horn algorithm. Irrespective of method, reference limits were expanded with the 98-percentile interval, but some expansions were small. Outlier exclusion contracted limits with more influence on the upper limit. The robust method contracted the upper limit to a meaningful degree and slightly expanded the lower limit for many analytes. Outlier exclusion and computation by the robust method have an increasing influence on analytes with right-skewed distributions of reference values from large populations not screened to exclude common, stable diseases and environmental factors that might affect analyte variability. The method has advantages for computation of reference limits used in clinical trial analyses.

The impact of preanalytical variables on measuring cerebrospinal fluid biomarkers for Alzheimer's disease diagnosis: A review.

INTRODUCTION: Cerebrospinal fluid (CSF) biomarkers have the potential to improve the diagnostic accuracy of Alzheimer's disease, yet there is a lack of harmonized preanalytical CSF handling protocols. METHODS: This systematic review summarizes the current literature on the influence of preanalytical variables on CSF biomarker concentration. We evaluated the evidence for three core CSF biomarkers: ß-amyloid 42, total tau, and phosphorylated tau. RESULTS: The clinically important variables with the largest amount of conflicting data included the temperature at which samples are stored, the time nonfrozen samples can be stored, and possible effects of additives such as detergents, blood contamination, and centrifugation. Conversely, we discovered that there is consensus that tube material has a significant effect. DISCUSSION: A unified CSF handling protocol is recommended to reduce preanalytical variability and facilitate comparison of CSF biomarkers across studies and laboratories. In future, experiments should use a gold standard with fresh CSF collected in low binding tubes.

The potent BACE1 inhibitor LY2886721 elicits robust central Aß pharmacodynamic responses in mice, dogs, and humans.

BACE1 is a key protease controlling the formation of amyloid ß, a peptide hypothesized to play a significant role in the pathogenesis of Alzheimer's disease (AD). Therefore, the development of potent and selective inhibitors of BACE1 has been a focus of many drug discovery efforts in academia and industry. Herein, we report the nonclinical and early clinical development of LY2886721, a BACE1 active site inhibitor that reached phase 2 clinical trials in AD. LY2886721 has high selectivity against key off-target proteases, which efficiently translates in vitro activity into robust in vivo amyloid ß lowering in nonclinical animal models. Similar potent and persistent amyloid ß lowering was observed in plasma and lumbar CSF when single and multiple doses of LY2886721 were administered to healthy human subjects. Collectively, these data add support for BACE1 inhibition as an effective means of amyloid lowering and as an attractive target for potential disease modification therapy in AD.

Phase 3 solanezumab trials: Secondary outcomes in mild Alzheimer's disease patients.

INTRODUCTION: EXPEDITION and EXPEDITION2 were identically designed placebo-controlled phase 3 studies assessing effects of solanezumab, an antiamyloid monoclonal antibody binding soluble amyloid-ß peptide, on cognitive and functional decline over 80 weeks in patients with mild-to-moderate Alzheimer's disease (AD). Primary findings for both studies have been published. METHODS: Secondary analyses of efficacy, biomarker, and safety endpoints in the pooled (EXPEDTION + EXPEDITION2) mild AD population were performed. RESULTS: In the mild AD population, less cognitive and functional decline was observed with solanezumab (n = 659) versus placebo (n = 663), measured by Alzheimer's Disease Assessment Scale Cognitive subscale, Mini-Mental State Examination, and Alzheimer's Disease Cooperative Study-Activities of Daily Living functional scale Instrumental ADLs. Baseline-to-endpoint changes did not differ between treatment groups for Alzheimer's Disease Cooperative Study-Activities of Daily Living functional scale, basic items of the ADCS-ADL, and Clinical Dementia Rating Sum of Boxes. Plasma/cerebrospinal fluid biomarker findings indicated target engagement by solanezumab. Solanezumab demonstrated acceptable safety. Efficacy findings for the moderate AD population are also provided. DISCUSSION: These findings describe solanezumab effects on efficacy/safety measures in a mild AD population. Another phase 3 study, EXPEDITION3, will investigate solanezumab's effects in a mild AD population.

Florbetapir positron emission tomography and cerebrospinal fluid biomarkers.

BACKGROUND: We evaluated the relationship between florbetapir-F18 positron emission tomography (FBP PET) and cerebrospinal fluid (CSF) biomarkers. METHODS: Alzheimer's Disease Neuroimaging Initiative-Grand Opportunity and Alzheimer's Disease Neuroimaging Initiative 2 (GO/2) healthy control (HC), mild cognitive impairment (MCI), and Alzheimer's disease (AD) dementia subjects with clinical measures and CSF collected ±90 days of FBP PET data were analyzed using correlation and logistic regression. RESULTS: In HC and MCI subjects, FBP PET anterior and posterior cingulate and composite standard uptake value ratios correlated with CSF amyloid beta (Aß1-42) and tau/Aß1-42 ratios. Using logistic regression, Aß1-42, total tau (t-tau), phosphorylated tau181P (p-tau), and FBP PET composite each differentiated HC versus AD. Aß1-42 and t-tau distinguished MCI versus AD, without additional contribution by FBP PET. Total tau and p-tau added discriminative power to FBP PET when classifying HC versus AD. CONCLUSION: Based on cross-sectional diagnostic groups, both amyloid and tau measures distinguish healthy from demented subjects. Longitudinal analyses are needed.

The Alzheimer's Disease Neuroimaging Initiative 2 Biomarker Core: A review of progress and plans.

INTRODUCTION: We describe Alzheimer's Disease Neuroimaging Initiative (ADNI) Biomarker Core progress including: the Biobank; cerebrospinal fluid (CSF) amyloid beta (Aß1-42), t-tau, and p-tau181 analytical performance, definition of Alzheimer's disease (AD) profile for plaque, and tangle burden detection and increased risk for progression to AD; AD disease heterogeneity; progress in standardization; and new studies using ADNI biofluids. METHODS: Review publications authored or coauthored by ADNI Biomarker core faculty and selected non-ADNI studies to deepen the understanding and interpretation of CSF Aß1-42, t-tau, and p-tau181 data. RESULTS: CSF AD biomarker measurements with the qualified AlzBio3 immunoassay detects neuropathologic AD hallmarks in preclinical and prodromal disease stages, based on CSF studies in non-ADNI living subjects followed by the autopsy confirmation of AD. Collaboration across ADNI cores generated the temporal ordering model of AD biomarkers varying across individuals because of genetic/environmental factors that increase/decrease resilience to AD pathologies. DISCUSSION: Further studies will refine this model and enable the use of biomarkers studied in ADNI clinically and in disease-modifying therapeutic trials.

Effects of duloxetine on norepinephrine and serotonin transporter activity in healthy subjects.

Duloxetine selectively inhibits the serotonin (5-HT) and norepinephrine (NE) transporters (5-HTT and NET, respectively), as demonstrated in vitro and in preclinical studies; however, transporter inhibition has not been fully assessed in vivo at the approved dose of 60 mg/d. Here, the in vivo effects of dosing with duloxetine 60 mg once daily for 11 days in healthy subjects were assessed in 2 studies: (1) centrally (n = 11), by measuring concentrations of 5-hydroxyindoleacetic acid, 3,4-dihydroxyphenylglycol (DHPG), and NE in cerebrospinal fluid, and (2) versus escitalopram 20 mg/d (n = 32) in a 2-period crossover study by assessing the ΔDHPG/ΔNE ratio in plasma during orthostatic testing and by pharmacokinetic/pharmacodynamic modeling of reuptake inhibition using subjects' serum in cell lines expressing cloned human 5-HTT or NET. At steady state, duloxetine significantly reduced concentrations of DHPG and 5-hydroxyindoleacetic acid (P < 0.05), but not NE, in cerebrospinal fluid; DHPG was also decreased in plasma and urine. The ΔDHPG/ΔNE ratio in plasma decreased significantly more with duloxetine than escitalopram (65% and 21%, respectively; P < 0.0001). Ex vivo reuptake inhibition of 5-HTT was comparable (EC50 = 44.5 nM) for duloxetine and escitalopram, but duloxetine inhibited NET more potently (EC50 = 116 nM and 1044 nM, respectively). Maximal predicted reuptake inhibition for 5-HTT was 84% for duloxetine and 80% for escitalopram, and that for NET was 67% and 14%, respectively. In summary, duloxetine significantly affected 5-HT and NE turnover in the central nervous system and periphery; these effects presumably occurred via inhibition of reuptake by the 5-HTT and NET, as indicated by effects on functional reuptake inhibition ex vivo.

A phase 2, placebo-controlled study of the opioid receptor antagonist LY2196044 for the treatment of alcohol dependence.

BACKGROUND: Endogenous opioid-mediated reward pathways may play a role in the development and maintenance of alcohol dependence. This study tested whether LY2196044, an opioid receptor antagonist, in combination with medical management would reduce drinking in alcohol-dependent patients. METHODS: This was a multicenter, outpatient, randomized, double-blind, parallel, and placebo-controlled trial with a 16-week treatment period. Patients (N = 375) were alcohol-dependent, treatment-seeking adults. Patients were randomly assigned to once-daily LY2196044 (final doses of 125 or 250 mg/d) or placebo. DNA samples were collected at baseline. At each visit, patients underwent safety assessments, laboratory testing, efficacy measures, and medical management. Blood samples were also obtained for pharmacokinetic testing. The primary measure was the change from baseline in the percent heavy drinking days (HDD). Secondary efficacy measures were percent days abstinent per month and number of drinks per day. RESULTS: The treatment difference in change from baseline in % HDD between LY2196044 and placebo was not statistically significant (-43.02 vs. -38.72%, respectively; p = 0.12). There was a trend toward greater change from baseline in the percent days abstinent per month for the LY2196044 group compared with the placebo group (33.49 vs. 28.12%, respectively; p = 0.051). The decrease from baseline for mean number of drinks per day was statistically significantly greater in the LY2196044 group compared with the placebo group (-5.37 vs. -4.66 drinks per day, respectively; p = 0.013). LY2196044-treated patients who were dopamine receptor type 4-variable number tandem repeat L carriers had greater reductions in % HDD (p = 0.0565), increased percent days abstinent (p = 0.0496), and reduced drinks per day (p = 0.0069) than placebo-treated L carriers. The safety profile for LY2196044 appeared similar to that of other opioid antagonists. CONCLUSIONS: The results from this proof-of-concept clinical trial warrant further evaluation of LY2196044 for the treatment of alcohol dependence.

Revisiting the framework of the National Institute on Aging-Alzheimer's Association diagnostic criteria.

In 2011, the National Institute on Aging and the Alzheimer's Association (NIA-AA) proposed revising the criteria for diagnosing Alzheimer's disease (AD), which had been established more than 25 years earlier by the National Institute on Neurologic and Communicative Disorders and Stroke (NINCDS) and the Alzheimer's Disease and Related Disorders Association (ADRDA), now called the Alzheimer's Association. The NIA-AA initiative also built upon research criteria for AD proposed by the International Working Group (IWG) in 2007 and updated in 2010. These efforts to revise the criteria reflect the need to improve diagnostic accuracy, facilitate clinical trials, and establish a common set of criteria that are universally accepted across domains of clinical practice, research, and drug development. To ensure that the proposed NIA-AA criteria remain as current as possible, the Alzheimer's Association Research Roundtable convened a meeting in Washington, DC, on October 1 and 2, 2012, bringing together international stakeholders from industry, academia, and regulatory agencies to identify areas of agreement and research gaps respective of NIA-AA criteria and IWG recommendations.

Robust central reduction of amyloid-ß in humans with an orally available, non-peptidic ß-secretase inhibitor.

According to the amyloid cascade hypothesis, cerebral deposition of amyloid-ß peptide (Aß) is critical for Alzheimer's disease (AD) pathogenesis. Aß generation is initiated when ß-secretase (BACE1) cleaves the amyloid precursor protein. For more than a decade, BACE1 has been a prime target for designing drugs to prevent or treat AD. However, development of such agents has turned out to be extremely challenging, with major hurdles in cell penetration, oral bioavailability/metabolic clearance, and brain access. Using a fragment-based chemistry strategy, we have generated LY2811376 [(S)-4-(2,4-difluoro-5-pyrimidin-5-yl-phenyl)-4-methyl-5,6-dihydro-4H-[1,3]thiazin-2-ylamine], the first orally available non-peptidic BACE1 inhibitor that produces profound Aß-lowering effects in animals. The biomarker changes obtained in preclinical animal models translate into man at doses of LY2811376 that were safe and well tolerated in healthy volunteers. Prominent and long-lasting Aß reductions in lumbar CSF were measured after oral dosing of 30 or 90 mg of LY2811376. This represents the first translation of BACE1-driven biomarker changes in CNS from preclinical animal models to man. Because of toxicology findings identified in longer-term preclinical studies, this compound is no longer progressing in clinical development. However, BACE1 remains a viable target because the adverse effects reported here were recapitulated in LY2811376-treated BACE1 KO mice and thus are unrelated to BACE1 inhibition. The magnitude and duration of central Aß reduction obtainable with BACE1 inhibition positions this protease as a tractable small-molecule target through which to test the amyloid hypothesis in man.

Safety and biomarker effects of solanezumab in patients with Alzheimer's disease.

OBJECTIVES: To assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of 12 weekly infusions of solanezumab, an anti-ß-amyloid (Aß) antibody, in patients with mild-to-moderate Alzheimer's disease. Cognitive measures were also obtained. METHODS: In this phase 2, randomized, double-blind, placebo-controlled clinical trial, 52 patients with Alzheimer's disease received placebo or antibody (100 mg every 4 weeks, 100 mg weekly, 400 mg every 4 weeks, or 400 mg weekly) for 12 weeks. Safety and biomarker evaluations continued until 1 year after randomization. Both magnetic resonance imaging and cerebrospinal fluid (CSF) examinations were conducted at baseline and after the active treatment period. The Aß concentrations were measured in plasma and CSF, and the Alzheimer's Disease Assessment Scale-cognitive portion was administered. RESULTS: Clinical laboratory values, CSF cell counts, and magnetic resonance imaging scans were unchanged by treatment, and no adverse events could be clearly related to antibody administration. Total (bound to antibody and unbound) Aß(1-40) and Aß(1-42) in plasma increased in a dose-dependent manner. Antibody treatment similarly increased total Aß(1-40) and Aß(1-42) in CSF. For patients taking 400 mg weekly, antibody treatment decreased unbound Aß(1-40) in CSF (P < .01), but increased unbound Aß(1-42) in CSF in a dose-dependent manner. The Alzheimer's Disease Assessment Scale-cognitive portion was unchanged after the 12-week antibody administration. CONCLUSIONS: Antibody administration was well tolerated with doses up to 400 mg weekly. The dose-dependent increase in unbound CSF Aß(1-42) suggests that this antibody may shift Aß equilibria sufficiently to mobilize Aß(1-42) from amyloid plaques.

Robust Pharmacodynamic Effect of LY3202626, a Central Nervous System Penetrant, Low Dose BACE1 Inhibitor, in Humans and Nonclinical Species.

BACKGROUND: The development of beta-site amyloid-beta precursor protein cleaving enzyme (BACE) 1 inhibitors for the treatment of Alzheimer's disease requires optimization of inhibitor potency, selectivity, and brain penetration. Moreover, there is a need for low-dose compounds since liver toxicity was found with some BACE inhibitors. OBJECTIVE: To determine whether the high in vitro potency and robust pharmacodynamic effect of the BACE inhibitor LY3202626 observed in nonclinical species translated to humans. METHODS: The effect of LY3202626 versus vehicle on amyloid-ß (Aß) levels was evaluated in a series of in vitro assays, as well as in in vivo and multi-part clinical pharmacology studies. Aß levels were measured using analytical biochemistry assays in brain, plasma, and cerebrospinal fluid (CSF) of mice, dogs and humans. Nonclinical data were analyzed using an ANOVA followed by Tukey's post hoc test and clinical data used summary statistics. RESULTS: LY3202626 exhibited significant human BACE1 inhibition, with an IC50 of 0.615±0.101 nM in a fluorescence resonance energy transfer assay and an EC50 of 0.275±0.176 nM for lowering Aß1-40 and 0.228±0.244 nM for Aß1-42 in PDAPP neuronal cultures. In dogs, CSF Aß1hboxx concentrations were significantly reduced by ∼80% at 9 hours following a 1.5 mg/kg dose. In humans, CSF Aß1-42 was reduced by 73.1±7.96 % following administration of 6 mg QD. LY3202626 was found to freely cross the blood-brain barrier in dogs and humans. CONCLUSION: LY3202626 is a potent BACE1 inhibitor with high blood-brain barrier permeability. The favorable safety and pharmacokinetic/pharmacodynamic profile of LY3202626 supports further clinical development.

N-(4-((2-(trifluoromethyl)-3-hydroxy-4-(isobutyryl)phenoxy)methyl)benzyl)-1-methyl-1H-imidazole-4-carboxamide (THIIC), a novel metabotropic glutamate 2 potentiator with potential anxiolytic/antidepressant properties: in vivo profiling suggests a link between behavioral and central nervous system neurochemical changes.

The normalization of excessive glutamatergic neurotransmission through the activation of metabotropic glutamate 2 (mGlu2) receptors may have therapeutic potential in a variety of psychiatric disorders, including anxiety/depression and schizophrenia. Here, we characterize the pharmacological properties of N-(4-((2-(trifluoromethyl)-3-hydroxy-4-(isobutyryl)phenoxy)methyl)benzyl)-1-methyl-1H-imidazole-4-carboxamide (THIIC), a structurally novel, potent, and selective allosteric potentiator of human and rat mGlu2 receptors (EC(50) = 23 and 13 nM, respectively). THIIC produced anxiolytic-like efficacy in the rat stress-induced hyperthermia assay and the mouse stress-induced elevation of cerebellar cGMP and marble-burying assays. THIIC also produced robust activity in three assays that detect antidepressant-like activity, including the mouse forced-swim test, the rat differential reinforcement of low rate 72-s assay, and the rat dominant-submissive test, with a maximal response similar to that of imipramine. Effects of THIIC in the forced-swim test and marble burying were deleted in mGlu2 receptor null mice. Analysis of sleep electroencephalogram (EEG) showed that THIIC had a sleep-promoting profile with increased non-rapid eye movement (REM) and decreased REM sleep. THIIC also decreased the dark phase increase in extracellular histamine in the medial prefrontal cortex and decreased levels of the histamine metabolite tele-methylhistamine (t-MeHA) in rat cerebrospinal fluid. Collectively, these results indicate that the novel mGlu2-positive allosteric modulator THIIC has robust activity in models used to predict anxiolytic/antidepressant efficacy, substantiating, at least with this molecule, differentiation in the biological impact of mGlu2 potentiation versus mGlu2/3 orthosteric agonism. In addition, we provide evidence that sleep EEG and CSF t-MeHA might function as viable biomarker approaches to facilitate the translational development of THIIC and other mGlu2 potentiators.

Qualification of the analytical and clinical performance of CSF biomarker analyses in ADNI.

The close correlation between abnormally low pre-mortem cerebrospinal fluid (CSF) concentrations of amyloid-ß1-42 (Aß(1-42)) and plaque burden measured by amyloid imaging as well as between pathologically increased levels of CSF tau and the extent of neurodegeneration measured by MRI has led to growing interest in using these biomarkers to predict the presence of AD plaque and tangle pathology. A challenge for the widespread use of these CSF biomarkers is the high variability in the assays used to measure these analytes which has been ascribed to multiple pre-analytical and analytical test performance factors. To address this challenge, we conducted a seven-center inter-laboratory standardization study for CSF total tau (t-tau), phospho-tau (p-tau(181)) and Aß(1-42) as part of the Alzheimer's Disease Neuroimaging Initiative (ADNI). Aliquots prepared from five CSF pools assembled from multiple elderly controls (n = 3) and AD patients (n = 2) were the primary test samples analyzed in each of three analytical runs by the participating laboratories using a common batch of research use only immunoassay reagents (INNO-BIA AlzBio3, xMAP technology, from Innogenetics) on the Luminex analytical platform. To account for the combined effects on overall precision of CSF samples (fixed effect), different laboratories and analytical runs (random effects), these data were analyzed by mixed-effects modeling with the following results: within center %CV 95% CI values (mean) of 4.0-6.0% (5.3%) for CSF Aß(1-42); 6.4-6.8% (6.7%) for t-tau and 5.5-18.0% (10.8%) for p-tau(181) and inter-center %CV 95% CI range of 15.9-19.8% (17.9%) for Aß(1-42), 9.6-15.2% (13.1%) for t-tau and 11.3-18.2% (14.6%) for p-tau(181). Long-term experience by the ADNI biomarker core laboratory replicated this degree of within-center precision. Diagnostic threshold CSF concentrations for Aß(1-42) and for the ratio t-tau/Aß(1-42) were determined in an ADNI independent, autopsy-confirmed AD cohort from whom ante-mortem CSF was obtained, and a clinically defined group of cognitively normal controls (NCs) provides statistically significant separation of those who progressed from MCI to AD in the ADNI study. These data suggest that interrogation of ante-mortem CSF in cognitively impaired individuals to determine levels of t-tau, p-tau(181) and Aß(1-42), together with MRI and amyloid imaging biomarkers, could replace autopsy confirmation of AD plaque and tangle pathology as the "gold standard" for the diagnosis of definite AD in the near future.

Hydrothermal carbonization of simulated food waste for recovery of fatty acids and nutrients.

We conducted Hydrothermal carbonization (HTC) of simulated food waste under different reaction conditions (180 to 220 °C, 15 and 30 min), with the aim of recovering both fatty acids from the hydrochar and nutrients from the aqueous-phase products. HTC of the simulated food waste produced hydrochar that retained up to 78% of the original fatty acids. These retained fatty acids were extracted from the hydrochar using ethanol, a food-grade solvent, and gave a net recovery of fatty acid of âˆ¼ 50%. The HTC process partitioned more than 50 wt% of the phosphorus and around 38 wt% of the nitrogen into the aqueous-phase products. A reaction path consistent with decarboxylation predominated during HTC under all of the reaction conditions investigated. A path consistent with dehydration was also observed, but only for the more severe reaction conditions. This work illustrates the potential that HTC has for valorization of food waste.

Proteomics of cerebrospinal fluid: methods for sample processing.

Cerebrospinal fluid (CSF) provides an important source of potential biomarkers for brain disorders and therapeutic drug development. Applications of proteomic technology to the identification and quantification of proteins in CSF are increasing rapidly. Key to obtaining reproducible and reliable data about protein levels in CSF are standardization of methods for sample collection, storage, and subsequent sample processing. Methods are described here for all steps of sample processing for a number of different proteomic approaches.

Central pharmacodynamic activity of solanezumab in mild Alzheimer's disease dementia.

INTRODUCTION: Solanezumab treatment was previously shown to significantly increase total (bound + unbound) cerebrospinal fluid (CSF) levels of amyloid ß (Aß)1-40 and Aß1-42 in patients with mild to moderate Alzheimer's disease dementia yet did not produce meaningful cognitive effects. This analysis assessed solanezumab's central nervous system target engagement by evaluating changes in CSF total and free Aß isoforms and their relationship with solanezumab exposure. METHODS: CSF Aß isoform concentrations were measured in patients with mild Alzheimer's disease dementia from a pooled EXPEDITION + EXPEDITION2 population and from EXPEDITION3. CSF solanezumab concentrations were determined from EXPEDITION3. RESULTS: Solanezumab produced statistically significant increases in CSF total Aß isoforms versus placebo, which correlated with CSF solanezumab concentration. Inconsistent effects on free Aß isoforms were observed. Solanezumab penetration into the central nervous system was low. DISCUSSION: Solanezumab administration engaged the central molecular target, and molar ratio analyses demonstrated that higher exposures may further increase CSF total Aß concentrations.

Derivation of cutoffs for the Elecsys® amyloid ß (1-42) assay in Alzheimer's disease.

INTRODUCTION: An Elecsys® Amyloid ß (Aß [1-42]) immunoassay cutoff for classification of patients with Alzheimer's disease was investigated. METHODS: Cerebrospinal fluid samples collected from patients with mild-to-moderate Alzheimer's disease were analyzed by Elecsys® immunoassays: (1) Aß (1-42), (2) total tau, and (3) phosphorylated tau. Cutoffs (Aß [1-42] and ratios with tau) were estimated by method comparison between AlzBio3 (n = 206), mixture modeling (n = 216), and concordance with florbetapir F 18 imaging-based classification (n = 75). RESULTS: A 1065-pg/mL (95% confidence interval: 985-1153) Elecsys® Aß (1-42) cutoff provided 94% overall percentage agreement with AlzBio3. Comparable cutoff estimates (95% confidence interval) were derived from mixture modeling (equally weighted: 1017 [949-1205] pg/mL; prevalence weighted: 1172 [1081-1344] pg/mL) and concordance with florbetapir F 18 imaging (visual read: 1198 [998-1591] pg/mL; automated: 1198 [1051-1638] pg/mL). DISCUSSION: Based on three approaches, a 1100-pg/mL Elecsys® Aß (1-42) cutoff is suitable for clinical trials with similar populations and preanalytical handling.