The γ-Secretase Modulator, BMS-932481, Modulates Aß Peptides in the Plasma and Cerebrospinal Fluid of Healthy Volunteers.

The pharmacokinetics, pharmacodynamics, safety, and tolerability of BMS-932481, a γ-secretase modulator (GSM), were tested in healthy young and elderly volunteers after single and multiple doses. BMS-932481 was orally absorbed, showed dose proportionality after a single dose administration, and had approximately 3-fold accumulation after multiple dosing. High-fat/caloric meals doubled the Cmax and area under the curve and prolonged Tmax by 1.5 hours. Consistent with the preclinical pharmacology of GSMs, BMS-932481 decreased cerebrospinal fluid (CSF) Aß39, Aß40, and Aß42 while increasing Aß37 and Aß38, thereby providing evidence of γ-secretase enzyme modulation rather than inhibition. In plasma, reductions in Aß40 and Aß42 were observed with no change in total Aß; in CSF, modest decreases in total Aß were observed at higher dose levels. Increases in liver enzymes were observed at exposures associated with greater than 70% CSF Aß42 lowering after multiple dosing. Although further development was halted due to an insufficient safety margin to test the hypothesis for efficacy of Aß lowering in Alzheimer's disease, this study demonstrates that γ-secretase modulation is achievable in healthy human volunteers and supports further efforts to discover well tolerated GSMs for testing in Alzheimer's disease and other indications.

Efficacy of adjunctive aripiprazole in patients with major depressive disorder whose symptoms worsened with antidepressant monotherapy.

INTRODUCTION: Efficacy of depression treatments, including adjunctive antipsychotic treatment, has not been explored for patients with worsening symptoms after antidepressant therapy (ADT). METHODS: This post-hoc analysis utilized pooled data from 3 similarly designed, randomized, double-blind, placebo-controlled trials that assessed the efficacy, safety, and tolerability of adjunctive aripiprazole in patients with major depressive disorder with inadequate response to ADT. The studies had 2 phases: an 8-week prospective ADT phase and 6-week adjunctive (aripiprazole or placebo) treatment phase. This analysis focused on patients whose symptoms worsened during the prospective 8-week ADT phase (worsening defined as >0% increase in Montgomery-Åsberg Depressive Rating Scale [MADRS] Total score). During the 6-week, double-blind, adjunctive phase, response was defined as ≥50% reduction in MADRS Total score and remission as ≥50% reduction in MADRS Total score and MADRS score ≤10. RESULTS: Of 1065 patients who failed to achieve a response during the prospective phase, 160 exhibited worsening of symptoms (ADT-Worseners), and 905 exhibited no change/reduction in MADRS scores (ADT-Non-worseners). Response rates for ADT-Worseners at endpoint were 36.6% (adjunctive aripiprazole) and 22.5% (placebo). Similarly, response rates at endpoint for ADT-Non-worseners were 37.5% (adjunctive aripiprazole) and 22.5% (placebo). Remission rates at endpoint for ADT-Worseners were 25.4% (adjunctive aripiprazole) and 12.4% (placebo). For ADT-Non-worseners, remission rates were 29.9% (adjunctive aripiprazole) and 17.4% (placebo). CONCLUSION: These results suggest that adjunctive aripiprazole is an effective intervention for patients whose symptoms worsen during antidepressant monotherapy. The results challenge the view that benefits of adjunctive therapy with aripiprazole are limited to partial responders to ADT.

Pharmacodynamics of selective inhibition of γ-secretase by avagacestat.

A hallmark of Alzheimer's disease (AD) pathology is the accumulation of brain amyloid ß-peptide (Aß), generated by γ-secretase-mediated cleavage of the amyloid precursor protein (APP). Therefore, γ-secretase inhibitors (GSIs) may lower brain Aß and offer a potential new approach to treat AD. As γ-secretase also cleaves Notch proteins, GSIs can have undesirable effects due to interference with Notch signaling. Avagacestat (BMS-708163) is a GSI developed for selective inhibition of APP over Notch cleavage. Avagacestat inhibition of APP and Notch cleavage was evaluated in cell culture by measuring levels of Aß and human Notch proteins. In rats, dogs, and humans, selectivity was evaluated by measuring plasma blood concentrations in relation to effects on cerebrospinal fluid (CSF) Aß levels and Notch-related toxicities. Measurements of Notch-related toxicity included goblet cell metaplasia in the gut, marginal-zone depletion in the spleen, reductions in B cells, and changes in expression of the Notch-regulated hairy and enhancer of split homolog-1 from blood cells. In rats and dogs, acute administration of avagacestat robustly reduced CSF Aß40 and Aß42 levels similarly. Chronic administration in rats and dogs, and 28-day, single- and multiple-ascending-dose administration in healthy human subjects caused similar exposure-dependent reductions in CSF Aß40. Consistent with the 137-fold selectivity measured in cell culture, we identified doses of avagacestat that reduce CSF Aß levels without causing Notch-related toxicities. Our results demonstrate the selectivity of avagacestat for APP over Notch cleavage, supporting further evaluation of avagacestat for AD therapy.

A contrast in safety, pharmacokinetics and pharmacodynamics across age groups after a single 50 mg oral dose of the γ-secretase inhibitor avagacestat.

AIM: To evaluate the single dose pharmacokinetics, pharmacodynamics, and preliminary tolerability of the γ-secretase inhibitor BMS-708163 (avagacestat) in young and elderly men and women. METHODS: All subjects received double-blinded administration of a single 50 mg dose of avagacestat in capsule form or matching placebo. Main evaluations included pharmacokinetics, safety, plasma amyloid-ß (Aß)(1-40) concentratios and exploration of Notch biomarkers. RESULTS: Avagacestat 50 mg capsule was well tolerated and rapidly absorbed among young and elderly subjects, with a median t(max) between 1 and 2 h post dose and an average half-life between 41 and 71 h. In general, subjects aged 75 years or more had higher AUC(0,∞) values than those aged less than 75 years. An exploratory analysis of Aß(1-40) serum concentrations showed a pattern of decreasing concentrations over the first 4-6 h followed by a rise above baseline that was maintained until the end of the assessment period. Adverse events were generally mild, occurring more frequently in elderly subjects, with no observed difference between subjects receiving avagacestat and placebo. No dose limiting gastrointestinal effects of avagacestat were observed and exploratory biomarkers of Notch inhibition did not change significantly. CONCLUSIONS: The favourable safety profile and pharmacokinetic effects of avagacestat in this study support its continued development, especially in the target population of elderly subjects with mild cognitive impairment or Alzheimer's disease.

Improving Alzheimer's disease phase II clinical trials.

Over the past 30 years, many drugs have been studied as possible treatments for Alzheimer's disease, but only four have demonstrated sufficient efficacy to be approved as treatments, of which three are in the same class. This lack of success has raised questions both in the pharmaceutical industry and academia about the future of Alzheimer's disease therapy. The high cost and low success rate of drug development across many disease areas can be attributed, in large part, to late-stage clinical failures (Schachter and Ramoni, Nat Rev Drug Discov 2007;6:107-8). Thus, identifying in phase II, or preferably phase I, drugs that are likely to fail would have a dramatic impact on the costs associated with developing new drugs. With this in mind, the Alzheimer's Association convened a Research Roundtable on June 23 and 24, 2011, in Washington, DC, bringing together scientists from academia, industry, and government regulatory agencies to discuss strategies for improving the probability of phase II trial results predicting success when considering the go/no-go decision-making process leading to the initiation of phase III.

Prophylactic Efficacy of Riluzole against Anxiety- and Depressive-Like Behaviors in Two Rodent Stress Models.

Introduction: Chronic stress-related illnesses such as major depressive disorder and post-traumatic stress disorder share symptomatology, including anxiety, anhedonia, and helplessness. Across disorders, neurotoxic dysregulated glutamate (Glu) signaling may underlie symptom emergence. Current first-line antidepressant drugs, which do not directly target Glu signaling, fail to provide adequate benefit for many patients and are associated with high relapse rates. Riluzole modulates glutamatergic neurotransmission by increasing metabolic cycling and modulating signal transduction. Clinical studies exploring riluzole's efficacy in stress-related disorders have provided varied results. However, the utility of riluzole for treating specific symptom dimensions or as a prophylactic treatment has not been comprehensively assessed. Methods: We investigated whether chronic prophylactic riluzole (∼12-15 mg/kg/day p.o.) could prevent the emergence of behavioral deficits induced by unpredictable chronic mild stress (UCMS) in mice. We assessed (i) anxiety-like behavior using the elevated-plus maze, open-field test, and novelty-suppressed feeding, (ii) mixed anxiety/anhedonia-like behavior in the novelty-induced hypophagia test, and (iii) anhedonia-like behavior using the sucrose consumption test. Z-scoring summarized changes across tests measuring similar dimensions. In a separate learned helplessness (LH) cohort, we investigated whether chronic prophylactic riluzole treatment could block the development of helplessness-like behavior. Results: UCMS induced an elevation in anhedonia-like behavior and overall behavioral emotionality that was blocked by prophylactic riluzole. In the LH cohort, prophylactic riluzole blocked the development of helplessness-like behavior. Discussion/Conclusion: This study supports the utility of riluzole as a prophylactic medication for preventing anhedonia and helplessness symptoms associated with stress-related disorders.

A phase Ib dose-escalation study of troriluzole (BHV-4157), an oral glutamatergic signaling modulator, in combination with nivolumab in patients with advanced solid tumors.

BACKGROUND: Glutamate signaling activates MAPK and PI3K/AKT pathways in tumor cells. Treatment with riluzole, a glutamate release inhibitor, has been previously shown to be safe in melanoma patients and produced biologic effects, but did not lead to radiographic responses, possibly due to poor pharmacokinetic properties. Therefore, we conducted a phase Ib trial to determine the safety and tolerability of the combination of the riluzole prodrug troriluzole (BHV-4157, trigriluzole) and the PD-1 antibody nivolumab in patients with advanced solid tumors. METHODS: Patients with advanced or refractory solid tumors and measurable disease per RECIST 1.1 were treated with increasing doses of troriluzole using a semi-Bayesian modified toxicity probability interval dose escalation procedure. Troriluzole monotherapy was orally self-administered for a 14-day lead-in period followed by continuation of troriluzole in combination with nivolumab 240 mg IV every 2 weeks. Endpoints included safety, pharmacokinetics (PK) and efficacy. RESULTS: We enrolled 14 patients with advanced solid tumors (melanoma = 3, NSCLC = 3, renal cell carcinoma = 2, bladder/urothelial = 2, ovarian cancer = 1, adenoid cystic carcinoma = 1, pleural mesothelial = 1, head and neck cancer = 1). Eleven patients had cancer progression on prior therapy with PD-1 or PD-L1 agent. Patients received troriluzole total daily doses from 140 to 560 mg (divided). The most common treatment-related adverse events (TRAE) occurring in ≥ 5 patients (> 35%) were transaminitis and increased lipase. DLT (dose-limiting toxicity) occurred in 3 patients: (1) grade 3 anorexia, (2) grade 3 fatigue and, (3) grade 3 atrial fibrillation. Six patients were treated at the MTD (maximum tolerated dose). No subjects discontinued treatment due to AEs. One response occurred (7%), which was a partial response in a subject who had PD-1 refractory disease. The 6-month PFS rate was 21%. PK data showed that the prodrug troriluzole was efficiently cleaved into riluzole by 2-h post-dosing in all dose cohorts tested. CONCLUSION: The combination of troriluzole and nivolumab was safe and well-tolerated. The MTD of troriluzole was determined to be 420 mg total daily dose. The observed antitumor activity, primarily disease stabilization, is of interest in patients with PD-1 resistant tumors. Trial Registration ClinicalTrials.gov Identifier NCT03229278.

Efficacy and safety of adjunctive aripiprazole in major depressive disorder in older patients: a pooled subpopulation analysis.

OBJECTIVES: To evaluate the efficacy and safety of adjunctive aripiprazole compared with standard antidepressant therapy (ADT) for older patients with major depressive disorder (MDD) who demonstrated an incomplete response to standard antidepressant monotherapy. METHODS: Data from three similar 14-week studies (an 8-week prospective ADT treatment phase and a 6-week randomized, double-blind phase) of aripiprazole augmentation were pooled for this post hoc analysis. Two age groups were defined: younger patients (aged 18-49 years) and older patients (aged 50-67 years). The older patient group was further divided into three subgroups: 50-55, 56-60, and 61-67 years. The efficacy endpoint was the mean change in Montgomery-Åsberg Depression Rating Scale (MADRS) total score from end of the prospective phase (Week 8) to endpoint (Week 14, last observation carried forward (LOCF)). Remission was defined as MADRS total score ≤10 at endpoint. RESULTS: Four hundred and nine older patients (placebo, n = 198; aripiprazole, n = 211) and 679 younger patients (placebo, n = 341; aripiprazole, n = 338) were included in this analysis. Older patients receiving aripiprazole demonstrated significantly greater improvement in MADRS total score versus placebo at Week 14 (-10.0 vs. -6.4; p < 0.001; LOCF), similar to the improvement seen in younger patients. Remission rates were significantly higher with aripiprazole versus placebo in older (32.5% vs. 17.1%; p < 0.001) and younger (26.9% vs. 16.4%; p < 0.001) patients. Akathisia was the most common adverse event in both the older (17.1%) and younger (26.0%) patient groups. CONCLUSIONS: Adjunctive aripiprazole was effective in improving depressive symptoms in older patients, 50-67 years, with MDD who have had an inadequate response to standard antidepressant medication.

A pooled MADRS/IDS cross-correlation analysis: clinician and patient self-report assessment of improvement in core depressive symptoms with adjunctive aripiprazole.

BACKGROUND: These analyses aimed to examine the pattern of improvement in depression symptoms with adjunctive aripiprazole. METHODS: Data were pooled (724 subjects: n = 356 placebo, n = 368 aripiprazole) from 2 double-blind, 6-week aripiprazole studies. Pearson correlation coefficients (r) were calculated between changes on the Montgomery-Asberg Depression Rating Scale (MADRS) line items and selected Inventory of Depressive Symptomatology (IDS) line items using last observation carried forward. The magnitude of change was expressed as a between-group effect size (ES). RESULTS: At end point, adjunctive aripiprazole demonstrated significant improvement versus antidepressant therapy alone in 8 of the 10 MADRS items (MADRS total score Cohen effect size = 0.37) and 12 of the 30 IDS items (IDS total score Cohen ES = 0.18). Analysis of correlation data identified 5 MADRS items assessing mood, lassitude, inability to feel, self-worth, and suicidal thoughts that correlated with similar IDS items; these showed a similar pattern of rapid, sustained response to adjunctive aripiprazole and a similar ES. Other symptoms associated with depression (tension associated with feeling anxious, irritability, and lack of concentration) did not show statistically significant changes on either scale at end point. The IDS identified an additional 3 important depression-related symptoms (diminished libido, view of self, and interpersonal sensitivity) that showed significant rapid and sustained improvement with adjunctive aripiprazole. CONCLUSIONS: This cross-correlation analysis confirmed that improvement in core depressive symptoms with adjunctive aripiprazole was identified by both clinicians and patients. Clinically, these changes were maintained during the study. Theoretically, these findings lead to important questions regarding neurochemical changes produced by aripiprazole when used in combination with antidepressants.

Assessing Effects of BHV-0223 40 mg Zydis Sublingual Formulation and Riluzole 50 mg Oral Tablet on Liver Function Test Parameters Utilizing DILIsym.

For patients with amyotrophic lateral sclerosis who take oral riluzole tablets, approximately 50% experience alanine transaminase (ALT) levels above upper limit of normal (ULN), 8% above 3× ULN, and 2% above 5× ULN. BHV-0223 is a novel 40 mg rapidly sublingually disintegrating (Zydis) formulation of riluzole, bioequivalent to conventional riluzole 50 mg oral tablets, that averts the need for swallowing tablets and mitigates first-pass hepatic metabolism, thereby potentially reducing risk of liver toxicity. DILIsym is a validated multiscale computational model that supports evaluation of liver toxicity risks. DILIsym was used to compare the hepatotoxicity potential of oral riluzole tablets (50 mg BID) versus BHV-0223 (40 mg BID) by integrating clinical data and in vitro toxicity data. In a simulated population (SimPops), ALT levels > 3× ULN were predicted in 3.9% (11/285) versus 1.4% (4/285) of individuals with oral riluzole tablets and sublingual BHV-0223, respectively. This represents a relative risk reduction of 64% associated with BHV-0223 versus conventional riluzole tablets. Mechanistic investigations revealed that oxidative stress was responsible for the predicted ALT elevations. The validity of the DILIsym representation of riluzole and assumptions is supported by its ability to predict rates of ALT elevations for riluzole oral tablets comparable with that observed in clinical data. Combining a mechanistic, quantitative representation of hepatotoxicity with interindividual variability in both susceptibility and liver exposure suggests that sublingual BHV-0223 confers diminished rates of liver toxicity compared with oral tablets of riluzole, consistent with having a lower overall dose of riluzole and bypassing first-pass liver metabolism.

A Pharmacokinetic Bioequivalence Study Comparing Sublingual Riluzole (BHV-0223) and Oral Tablet Formulation of Riluzole in Healthy Volunteers.

Orally administered riluzole extends survival in patients with amyotrophic lateral sclerosis, although it has significant shortcomings (eg, adverse events, dysphagic patients) that limit its utility. BHV-0223 is a Zydis-based orally disintegrating formulation of riluzole designed for sublingual administration that addresses the limitations of conventional tablets. This study assessed the bioequivalence between 40-mg BHV-0223 and standard 50-mg oral riluzole tablets, and the food effect on BHV-0223 pharmacokinetics in healthy volunteers. Overall, 133 healthy subjects received BHV-0223 and riluzole tablets under fasted conditions. Geometric mean ratios for the area under the plasma concentration-time curve (AUC) from time zero to time of last nonzero concentration (AUC0-t ) (89.9%; confidence interval [CI], 87.3%-92.5%), AUC from time zero to infinity (AUC0-∞ ) (89.8%; CI, 87.3%-92.4%), and maximum observed concentration (112.7%; CI, 105.5%-120.4%) all met bioequivalence criteria (80%-125%). Subsequently, 67 subjects received BHV-0223 under fed conditions. The geometric mean ratios of AUC0-t (91.2%; CI, 88.1-94.3%), and AUC0-∞ (92.0%; CI, 89.0-95.1%) were similar, but maximum observed concentration ratios were not within bioequivalence criteria. BHV-0223 was well tolerated. This study demonstrated that 40-mg sublingual BHV-0223 is bioequivalent to 50-mg oral riluzole tablets.

Metabolic assessment of aripiprazole as adjunctive therapy in major depressive disorder: a pooled analysis of 2 studies.

In 2 identical multicenter, double-blind, placebo-controlled trials, an 8-week prospective treatment phase to ensure inadequate response to standard antidepressants was followed with 6 weeks of aripiprazole (2-20 mg/d) or placebo, plus a standard antidepressant. This pooled analysis involving 737 patients across the 2 studies evaluated the metabolic effects of adjunctive aripiprazole in patients with major depressive disorder. Outcomes included mean change from end of prospective treatment phase to endpoint in body weight, waist circumference, fasting levels of total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides (TG), fasting plasma glucose, and glycosylated hemoglobin (hemoglobin A1C). Logistic regression determined whether baseline variables were associated with weight gain or whether weight change was associated with clinical outcome. Statistically significant increases occurred in mean body weight (adjunctive aripiprazole, +1.73 kg, vs adjunctive placebo, +0.38 kg; P < 0.001). Significantly more subjects receiving adjunctive aripiprazole had clinically relevant (> or = 7%) weight gain versus placebo (5.2% vs 0.6%; P < 0.001). More patients treated with adjunctive aripiprazole shifted body mass index category group from normal to overweight and from overweight to obese than those treated with adjunctive placebo. Body mass index, sex, age, Montgomery-Asberg Depression Rating Scale score, fasting TG, fasting glucose, and standard antidepressants were not clinically meaningful predictors of weight gain with adjunctive aripiprazole, and change in weight had no correlation with clinical outcome. Adjunctive aripiprazole produced no significant changes versus placebo in mean waist circumference, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, TG, fasting plasma glucose, or hemoglobin A1C. Also, there was no apparent change in the incidence of National Cholesterol Education Program-defined abnormal metabolic measures after treatment with aripiprazole.

Aripiprazole augmentation in major depressive disorder: a double-blind, placebo-controlled study in patients with inadequate response to antidepressants.

INTRODUCTION: Effective management of major depressive disorder (MDD) continues to be a challenging task for psychiatrists and primary care physicians. This trial evaluated the efficacy and safety of adjunctive aripiprazole versus antidepressant monotherapy in patients with MDD and independently replicated the positive findings of two similar trials. METHODS: Patients (N=1,147) with MDD experiencing a major depressive episode and a history of inadequate response to antidepressant monotherapy were enrolled (week 0); 827 received single-blind adjunctive placebo plus open-label antidepressant (escitalopram, fluoxetine, paroxetine controlled release, sertraline, or venlafaxine extended release) for 8 weeks to confirm inadequate response to antidepressants; 349 patients with inadequate response were randomized (1:1) to double-blind, adjunctive placebo (n=172) or adjunctive aripiprazole (n=177; 2-20 mg/day). Primary outcome was the mean change in Montgomery-Asberg Depression Rating Scale (MADRS) Total score from baseline (week 8) to endpoint (week 14). RESULTS: Clinically significant improvements in depressive symptoms as assessed by decreases in the MADRS Total score were greater with adjunctive aripiprazole (-10.1) than placebo (-6.4; P<.001). Remission rates were greater for adjunctive aripiprazole than for adjunctive placebo (week 14, 36.8% vs 18.9%; P<.001). Completion rates with adjunctive aripiprazole and placebo were high (83% vs. 87%) and discontinuations due to adverse events were low (6.2% vs 1.7%). CONCLUSION: For some patients with MDD who do not obtain adequate symptom relief with antidepressant monotherapy, adjunctive therapies can significantly improve depressive symptoms. As reported, adjunctive aripiprazole was associated with a two-fold higher remission rate than adjunctive placebo. This, and previous studies, have shown that discontinuations due to adverse events were low and completion rates were high, and has indicated that both antidepressant and aripiprazole in combination were relatively well-tolerated and safe. This is the third consecutive clinical trial, in the absence of a failed trial, to demonstrate that aripiprazole augmentation to antidepressants is an efficacious and well-tolerated treatment for patients with MDD who do not respond adequately to standard antidepressant monotherapy (ClinicalTrials.gov study NCT00105196).

Examining the efficacy of adjunctive aripiprazole in major depressive disorder: a pooled analysis of 2 studies.

BACKGROUND: Patients with major depressive disorder (MDD) who fail to achieve complete remission with antidepressant therapy may benefit from augmentation therapy with an atypical antipsychotic. METHOD: A pooled analysis was performed on 2 identical 14-week studies (8-week prospective antidepressant therapy treatment phase followed by 6-week randomized double-blind phase) evaluating the efficacy of adjunctive aripiprazole (2-20 mg/day) in DSM-IV-TR-defined MDD patients with an inadequate response to antidepressant therapy. Primary efficacy endpoint was the mean change in Montgomery-Asberg Depression Rating Scale (MADRS) total score from end of the prospective phase (week 8) to end of randomized phase (week 14, last observation carried forward). Subgroup analyses were performed. The key secondary endpoint was mean change in Sheehan Disability Scale (SDS) mean score. RESULTS: At endpoint, mean change in MADRS total score was significantly greater with adjunctive aripiprazole (-8.7) than with adjunctive placebo (-5.7; p < .001). Except for a differential treatment-by-sex interaction, change in MADRS total scores were consistently greater with adjunctive aripiprazole than with adjunctive placebo, regardless of race, age, episode duration, prior antidepressant therapy response, number of historical treatment failures, severity of depressive symptoms, and antidepressant. At endpoint, MADRS remission rates were significantly greater with adjunctive aripiprazole than with placebo (25.7% vs. 15.4%; p < .001). Adjunctive aripiprazole also demonstrated significantly greater improvements in mean change from baseline in SDS total score than adjunctive placebo (-1.2 vs. -0.6; p = .001). CONCLUSION: Augmentation of antidepressant therapy with the atypical antipsychotic aripiprazole resulted in significant efficacy benefits across a range of subgroups of patients with MDD. Further study of a treatment-by-sex interaction is needed. TRIAL REGISTRATION: www.clinicaltrials.gov Identifiers: NCT00095823 and NCT00095758.

Sex differences in diencephalon serotonin transporter availability in major depression.

BACKGROUND: Major depression is more prevalent in women than men. The present study evaluated if previous findings that demonstrated decreased 5-hydroxytryptamine (5-HT) transporter availability in depressed patients would be confirmed in a larger sample and also evaluated sex differences. METHODS: Depressed (n = 32) and healthy subjects (n = 32), including 16 pairs of women and men, participated in an iodine-123-2 beta-carbomethoxy-3beta-(4-iodophenyltropane) ([(123)I]beta-CIT) single photon emission computed tomography (SPECT) and a magnetic resonance imaging (MRI) scan. Participants were administered [(123)I]beta-CIT (225.7 +/- 3.7 MBq) and imaged 23.0 +/- 1.6 hours later. Statistical analyses included analysis of variance and a regression analysis of the main and interactive effects of age, sex, and depression. RESULTS: Overall, depressed patients demonstrated 12% lower diencephalon and no change in striatal or brainstem [(123)I]beta-CIT uptake. Significant age by sex, sex by depression, and age by sex by depression interactions were noted due to 22% lower diencephalon [(123)I]beta-CIT uptake in depressed women compared with less than a 1% decrease in depressed men. CONCLUSIONS: As observed previously, diencephalon 5-HT transporter availability is decreased in depressed patients. However, the decrease appears to be sex-specific and age-dependent. These findings suggest that serotonergic mechanisms mediating depressed mood differ between men and women in an age-dependent manner and may explain why young women respond better to treatment with selective serotonin reuptake inhibitor (SSRI) antidepressants.

Cerebrovascular reactivity following administration of mirtazapine in healthy probands--a randomized, placebo controlled double-blind clinical study.

INTRODUCTION: Cerebrovascular reactivity (CVR) reflects the compensatory dilatory capacity of cerebral arterioles to a dilatory stimulus and is important for maintaining constant cerebral blood flow. A reduced CVR increases the risk of stroke. We recently found that CVR was reduced in patients with depression. This might contribute to the higher risk of stroke that has been found in subjects suffering from depression. The characterization of pathophysiological conditions in the cerebral circulation requires the knowledge of influencing factors on CVR. We therefore investigated the influence that antidepressant administration might have on CVR in humans. METHODS: We investigated CVR in 48 healthy men before and after a 10-day application of either mirtazapine or placebo. CVR was determined by calculating the increase in cerebral blood flow velocity after stimulation with acetazolamide. Blood flow velocities were measured by transcranial Doppler ultrasound. RESULTS: There was no significant group-difference of CVR after the treatment trial compared to baseline. DISCUSSION: Mirtazapine does not seem to have an influence on CVR, or any impact on CVR might have been quickly limited by a cerebral autoregulatory response.

Cognitive function over the treatment course of depression in middle-aged patients: correlation with brain MRI signal hyperintensities.

INTRODUCTION: It has been proposed that the often found hyperintensities on MRI representing vascular changes might be correlated with a worse outcome of cognitive malfunction in depression. The purpose of this study was to evaluate neuropsychological status in the acute depressed state and following remission and to investigate the potential relationship between MRI hyperintensities and neuropsychological functioning through the treatment course in a group of middle-aged depressed patients. MATERIALS AND METHODS: Twenty-seven depressed patients were assessed by a series of neuropsychological tests at the beginning of the depressive episode and again after an euthymic phase of 6 months following treatment. Thirty healthy controls were tested at comparable intervals. In all patients and controls a MRI was performed to identify hyperintensities representing a possible correlation with test performance during treatment course. RESULTS: At the onset of a depressive episode patients performed significantly worse than the controls in all tests. After sustained remission the patient group still performed significantly worse in verbal memory and verbal fluency compared to controls. There were no significant correlations between number of presence of vascular risk factors, or presence of hyperintensities on MRI, and cognitive abilities at either time point. DISCUSSION: These findings favor the hypothesis that some neuropsychological deficits might persist following treatment for depression, even in middle-aged patients. We found, however, that any residual cognitive deficit is not associated with MRI-hyperintensities in this age-group.

Comparison of "Word" vs. "Picture" Version of the Free and Cued Selective Reminding Test (FCSRT) in Older Adults.

BACKGROUND: This study examined the psychometric relationship between the Word and Picture versions of the Free and Cued Selective Reminding Test (FCSRT) and developed an equation for score conversion. METHODS: 187 participants were administered the FCSRT-Picture and FCSRT-Word on two visits using a randomized counterbalanced design. RESULTS: Participants had a mean age of 82.1 (sd=5.4) and mean education of 14.5 (sd=3.3) years. Mean FCSRT-Picture Free Recall score (mean 33.0, range: 17-44) was 7.9 points higher than the Word score (mean 25.1, range: 3-43). The Picture and Word FCSRT correlations for Free Recall and Total Recall were r=0.56, p<0.01 and r=0.46, p<0.01, respectively. DISCUSSION: The Picture and Word versions of the FCSRT were moderately associated in a sample of cognitively normal older adults. The score mean differences and variability between FCSRT-Picture and FCSRT-Word indicate that their scores should not be considered equivalent.

Targeting Prodromal Alzheimer Disease With Avagacestat: A Randomized Clinical Trial.

IMPORTANCE: Early identification of Alzheimer disease (AD) is important for clinical management and affords the opportunity to assess potential disease-modifying agents in clinical trials. To our knowledge, this is the first report of a randomized trial to prospectively enrich a study population with prodromal AD (PDAD) defined by cerebrospinal fluid (CSF) biomarker criteria and mild cognitive impairment (MCI) symptoms. OBJECTIVES: To assess the safety of the γ-secretase inhibitor avagacestat in PDAD and to determine whether CSF biomarkers can identify this patient population prior to clinical diagnosis of dementia. DESIGN, SETTING, AND PARTICIPANTS: A randomized, placebo-controlled phase 2 clinical trial with a parallel, untreated, nonrandomized observational cohort of CSF biomarker-negative participants was conducted May 26, 2009, to July 9, 2013, in a multicenter global population. Of 1358 outpatients screened, 263 met MCI and CSF biomarker criteria for randomization into the treatment phase. One hundred two observational cohort participants who met MCI criteria but were CSF biomarker-negative were observed during the same study period to evaluate biomarker assay sensitivity. INTERVENTIONS: Oral avagacestat or placebo daily. MAIN OUTCOMES AND MEASURE: Safety and tolerability of avagacestat. RESULTS: Of the 263 participants in the treatment phase, 132 were randomized to avagacestat and 131 to placebo; an additional 102 participants were observed in an untreated observational cohort. Avagacestat was relatively well tolerated with low discontinuation rates (19.6%) at a dose of 50 mg/d, whereas the dose of 125 mg/d had higher discontinuation rates (43%), primarily attributable to gastrointestinal tract adverse events. Increases in nonmelanoma skin cancer and nonprogressive, reversible renal tubule effects were observed with avagacestat. Serious adverse event rates were higher with avagacestat (49 participants [37.1%]) vs placebo (31 [23.7%]), attributable to the higher incidence of nonmelanoma skin cancer. At 2 years, progression to dementia was more frequent in the PDAD cohort (30.7%) vs the observational cohort (6.5%). Brain atrophy rate in PDAD participants was approximately double that of the observational cohort. Concordance between abnormal amyloid burden on positron emission tomography and pathologic CSF was approximately 87% (κ = 0.68; 95% CI, 0.48-0.87). No significant treatment differences were observed in the avagacestat vs placebo arm in key clinical outcome measures. CONCLUSIONS AND RELEVANCE: Avagacestat did not demonstrate efficacy and was associated with adverse dose-limiting effects. This PDAD population receiving avagacestat or placebo had higher rates of clinical progression to dementia and greater brain atrophy compared with CSF biomarker-negative participants. The CSF biomarkers and amyloid positron emission tomography imaging were correlated, suggesting that either modality could be used to confirm the presence of cerebral amyloidopathy and identify PDAD. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00890890.

Monoamine depletion in unmedicated depressed subjects.

BACKGROUND: Although significant evidence suggests that diminished monoamine function is associated with clinical depression, catecholamine or indoleamine depletion alone has not been associated with significant mood changes in unmedicated depressed subjects or never-depressed control subjects. This study assesses the integrated role of these monoamine systems in depressed patients. METHODS: Unmedicated depressed subjects underwent a 2-week, double-blind, random-ordered crossover study consisting of the following active and control conditions respectively: indoleamine (via tryptophan depletion) plus catecholamine (via alpha-methyl-paratyrosine administration) depletion and, separately, indoleamine plus sham (via diphenhydramine administration) catecholamine depletion. Ten subjects completed both conditions; two subjects were withdrawn after active testing and one after control testing. RESULTS: Mean Hamilton Depression Rating Scale (HDRS) scores decreased progressively throughout the study days (baseline 26.7 points +/- 1.7 SEM and termination 20.0 +/- 2.4, active depletion; baseline 26.1 points +/- 2.3 SEM and termination 23.2 +/- 2.6, control testing) but did not differ between groups. Only three patients demonstrated 20% or greater increases from baseline HDRS at any point during the observation days. CONCLUSIONS: Overall, results show that simultaneous disruptions of indoleamine and catecholamine function do not exacerbate symptoms in unmedicated depressed subjects, thus lending further support to the notion that monoamines regulate mood in actively depressed patients via indirect mechanisms.