Comparison of polysomnography in people with Alzheimer's disease and insomnia versus non-demented elderly people with insomnia

BACKGROUND

We used baseline polysomnography (PSG) data obtained during the clinical program development for suvorexant to compare the PSG profiles of people with Alzheimer's disease and insomnia (ADI) versus age-matched elderly individuals with insomnia (EI).

METHODS

Sleep laboratory baseline PSG data from participants age 55-80 years from 2 trials in people with insomnia and a trial in people with ADI were included. ADI participants had dementia of mild-to-moderate severity. Diagnostic criteria for insomnia, exclusion for other sleep problems, PSG recording procedures, and endpoint derivations were similar across the trials. All participants underwent a night of in-laboratory PSG prior to the baseline night to allow for screening/adaptation. Participants in the EI and ADI groups were compared with regard to sleep architecture, sleep micro-structure, and quantitative EEG power spectral endpoints. The analysis was performed on a post hoc basis using propensity score matching to compare sleep parameters separately in women and men while accounting for age group and total sleep time.

RESULTS

A total of 837 EI and 239 ADI participants were included, with the majority in each population (∼65%) being women. Compared to EI, those with ADI had a lower percentage of time spent in slow wave sleep (and a corresponding higher percentage of time spent in the lighter N1 sleep), a lower number of spindles per minute of N2 sleep, and lower absolute EEG power during NREM sleep, particularly in the lower-frequency bands. Trends for lower REM sleep percentage in ADI did not reach statistical significance.

CONCLUSIONS

Our findings in this large data set, in which the influence of sleep problems was effectively subtracted out (since both groups had insomnia), provide strong confirmatory support of results from previous smaller studies in indicating that AD of mild-to-moderate severity is associated with less slow wave sleep, spindles, and lower-frequency EEG power.

TRIAL REGISTRATION

ClinicalTrials.gov, numbers NCT01097616, NCT01097629, NCT02750306.

Progression from Prodromal Alzheimer's Disease to Mild Alzheimer's Disease Dementia in the Verubecestat APECS Study: Adjudicating Diagnostic Transitions

BACKGROUND

Delay of progression from prodromal Alzheimer's disease (AD) to dementia is an important outcome in AD trials. Centralized adjudication is intended to improve the consistency of dementia diagnosis but has not been scrutinized.

OBJECTIVE

To evaluate centralized adjudication for determining progression to dementia compared with Site Investigator opinion or change in Clinical Dementia Rating (CDR).

METHODS

We used data from the 2-year APECS trial of verubecestat versus placebo in 1,451 prodromal AD participants. Cases were triggered for central adjudication if: 1) the Site Investigator judged the participant had progressed to dementia, or 2) the participant's CDR sum-of-boxes score increased ≥2 points from baseline. Post-hoc analyses were performed on pooled treatment-group data to compare methods of assessing progression.

RESULTS

581/1,451 (40%) participants had changes triggering adjudication and most (83%) were confirmed as progression to dementia. Only 66% of those who met CDR criteria (regardless of whether they also met Site Investigator criteria) were adjudicated to have progressed to dementia and just 15% of those who met only CDR criteria were adjudicated to have progressed, representing 5% of progressors. In contrast, 99% of those who met Site Investigator criteria (regardless of whether they also met CDR criteria) were adjudicated to have progressed, and the same was true for those who met only Site Investigator criteria.

CONCLUSION

A positive Site Investigator opinion is an excellent predictor for a positive adjudication decision regarding onset of dementia. Conversely, sole use of CDR sum-of-boxes change ≥2 is inadequate. The benefit of centralized adjudication appears doubtful.

Pilot evaluation of a consumer wearable device to assess sleep in a clinical polysomnography trial of suvorexant for treating insomnia in patients with Alzheimer's disease

The orexin receptor antagonist suvorexant was previously reported to significantly improve total sleep time (TST), by 28 min per night versus placebo after 4 weeks, in a sleep laboratory polysomnography (PSG) study of patients with Alzheimer's disease and insomnia. The study included an exploratory evaluation of a consumer-grade wearable "watch" device for assessing sleep that we report on here. Participants who met diagnostic criteria for both probable Alzheimer's disease dementia and insomnia were randomized to suvorexant 10-20 mg (N = 142) or placebo (N = 143) in a double-blind, 4-week trial. Patients were provided with a consumer-grade wearable watch device (Garmin vívosmart^® HR) to be worn continuously. Overnight sleep laboratory PSG was performed on three nights: screening, baseline and Night 29 (last dose). Watch treatment effects were assessed by change-from-baseline in watch TST at Week 4 (average TST per night). We also analysed Night 29 data only, with watch data restricted to the PSG recording time. In the 193 participants included in the Week 4 watch analysis (suvorexant = 97, placebo = 96), the suvorexant-placebo difference in watch TST was 4 min (p = .622). In patients with usable data for both assessments at the baseline and Night 29 PSG (suvorexant = 57, placebo = 50), the watch overestimated TST compared to PSG (e.g., placebo baseline = 412 min for watch and 265 min for PSG) and underestimated change-from-baseline treatment effects: the suvorexant-placebo difference was 20 min for watch TST (p = .405) and 35 min for PSG TST (p = .057). These findings show that the watch was less sensitive than PSG for evaluating treatment effects on TST.

378 Use of a Clinician’s Global Impression of Severity scale to measure insomnia severity in Alzheimer’s disease-dementia patients

Introduction

Full montage polysomnography (PSG) is the gold standard for the objective evaluation of sleep but is time consuming and inaccessible to most clinicians. A Clinician’s Global Impression of Severity (CGI-S) scale can be used in clinical practice to provide a subjective assessment of patients’ insomnia severity. However, the utility of a CGI-S scale for assessing insomnia in patients with Alzheimer’s disease (AD)-dementia is not well understood. In a recent Phase III randomized, placebo-controlled clinical trial (NCT02750306), patients on suvorexant with AD-dementia and insomnia showed improvements in both PSG total sleep time (TST) and CGI-S scores. We conducted additional analyses to examine the association between CGI-S and PSG-TST to inform on the possible use of a CGI-S scale to assess insomnia severity in patients with AD-dementia in real-world settings.

Methods

Patients (N=285) met clinical diagnostic criteria for both probable mild-to-moderate AD-dementia and insomnia. The primary endpoint was change-from-baseline in overnight PSG-TST at Week-4. A single-item CGI-S rating of insomnia with responses of 1 (normal, not ill at all) to 7 (among the most extremely ill patients) was completed by a trained rater at baseline and after 2 and 4 weeks. CGI-S was an exploratory endpoint. Post-hoc correlational analyses and analyses of distribution of change-from-baseline to Week-4 in CGI-S response categories were performed.

Results

Pearson correlation indicated a significant association at baseline between PSG-TST and CGI-S (r=-0.18, nominal p=0.004). A correlation of change-from-baseline to Week-4 also indicated an association between PSG-TST and CGI-S (r=-0.24, nominal p<.0001). The distribution of change in CGI-S response category results at Week-4 showed that, compared to placebo, numerically less patients on suvorexant remained stable or worsened by >1 response category (21.8% vs. 29.4%, respectively) and numerically more improved by ≥1 response category (73.3% vs. 67.9%, respectively).

Conclusion

Our findings suggest that a CGI-S scale may be a useful tool for assessing insomnia severity in mild-to-moderate AD-dementia patients. Future studies with these patients are needed to determine the utility of a CGI-S scale in real-world settings.

Support (if any)

This study was funded by Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA

BACE inhibition causes rapid, regional, and non-progressive volume reduction in Alzheimer's disease brain

In the phase 3 EPOCH trial (Clinicaltrials.gov; NCT01739348), treatment with the BACE inhibitor verubecestat failed to improve cognition in patients with mild-to-moderate Alzheimer's disease, but was associated with reduced hippocampal volume after 78 weeks as assessed by MRI. The aims of the present exploratory analyses were to: (i) characterize the effect of verubecestat on brain volume by evaluating the time course of volumetric MRI changes for a variety of brain regions; and (ii) understand the mechanism through which verubecestat might cause hippocampal (and other brain region) volume loss by assessing its relationship to measures of amyloid, neurodegeneration, and cognition. Participants were aged 55-85 years with probable Alzheimer's disease dementia and a Mini Mental State Examination score ≥15 and ≤26. MRIs were obtained at baseline and at Weeks 13, 26, 52 and 78 of treatment. MRIs were segmented using Freesurfer and analysed using a tensor-based morphometry method. PET amyloid data were obtained with 18F-flutemetamol (Vizamyl®) at baseline and Week 78. Standardized uptake value ratios were generated with subcortical white matter as a reference region. Neurofilament light chain in the CSF was assessed as a biomarker of neurodegeneration. Compared with placebo, verubecestat showed increased MRI brain volume loss at Week 13 with no evidence of additional loss through Week 78. The verubecestat-related volumetric MRI loss occurred predominantly in amyloid-rich brain regions. Correlations between amyloid burden at baseline and verubecestat-related volumetric MRI reductions were not significant (r = 0.05 to 0.26, P-values > 0.27). There were no significant differences between verubecestat and placebo in changes from baseline in CSF levels of neurofilament light chain at Week 78 (increases of 7.2 and 14.6 pg/ml for verubecestat versus 19.7 pg/ml for placebo, P-values ≥ 0.1). There was a moderate correlation between volumetric MRI changes and cognitive decline in all groups including placebo at Week 78 (e.g. r = -0.45 to -0.55, P < 0.001 for whole brain), but the correlations were smaller at Week 13 and significant only for the verubecestat groups (e.g. r = -0.15 and -0.11, P < 0.04 for whole brain). Our results suggest that the verubecestat-associated MRI brain volume loss is not due to generalized, progressive neurodegeneration, but may be mediated by specific effects on BACE-related amyloid processes.

Use of the single-item Patient Global Impression-Severity scale as a self-reported assessment of insomnia severity

We evaluated a single-item Patient Global Impression-Severity (PGI-S) scale for assessing insomnia severity during the clinical development programme for suvorexant. The analyses used data from two randomised, double-blind, placebo-controlled, 3-month, Phase III clinical trials of suvorexant in patients with Diagnostic and Statistical Manual of Mental Disorders IV criteria insomnia. Patients assessed insomnia severity during the previous week using the PGI-S, a one-item questionnaire containing six response options ranging from 0 (none) to 5 (very severe), at baseline and at Week 2, and Months 1, 2, and 3 after randomisation. The seven-item Insomnia Severity Index (ISI) and other subjective and objective assessments were also completed by patients. PGI-S responses were compared primarily with the ISI using descriptive statistics and correlations. The PGI-S demonstrated favourable measurement characteristics (validity, reliability, responsiveness and sensitivity). PGI-S scores decreased from baseline to Month 3 in a similar pattern to the ISI total score, and the Spearman correlation coefficient between PGI-S and the ISI was .73. An improvement of ≥2 points on the PGI-S defined a treatment responder, based on comparison to the ISI definition of a responder (improvement of ≥6 points). Our present findings suggest that the PGI-S is a simple but valid, reliable, responsive, sensitive, and meaningful patient-reported assessment of insomnia severity. The PGI-S may be particularly useful as a companion outcome to sleep monitoring using wearable sleep devices or smartphones in at-home settings.

0487 Effects of Suvorexant on Sleep Architecture in Patients with Alzheimer’s Disease and Insomnia

Introduction

Suvorexant, an orexin receptor antagonist that enables sleep to occur via competitive antagonism of wake-promoting orexins, improved total sleep time (TST) in a sleep laboratory polysomnography (PSG) study of patients with AD and insomnia. Here we report on the effects of suvorexant on sleep architecture in the study.

Methods

This was a randomized, double-blind, 4-week trial (ClinicalTrials.gov NCT02750306). Participants who met diagnostic criteria for both probable AD dementia (of mild to moderate severity) and insomnia were randomized to suvorexant 10mg (could be increased to 20mg based on clinical response) or matching placebo. Overnight sleep laboratory PSG was performed on 3 nights: screening, baseline, and Night-29 (last night of dosing). Suvorexant differences from placebo in changes-from-baseline at Night-29 for sleep architecture were analyzed as exploratory endpoints.

Results

A total of 274 participants were included in the analysis (suvorexant N=135, placebo N=139). At Night-29, suvorexant improved TST by 28 minutes versus placebo (p=0.001). There were no significant differences between suvorexant and placebo in the % of TST spent in REM (1.3%, 95% CI: -0.5, 3.0), N1 (0.6%, 95% CI: -1.2, 2.5), N2 (-1.0%, 95% CI: -3.2, 1.2), or N3 (-0.6%, 95% CI: -1.8, 0.6). There was no significant difference between suvorexant and placebo in latency to REM (-5.4 minutes, 95% CI: -23.4, 12.7).

Conclusion

Suvorexant improves TST without altering the underlying sleep architecture in AD patients with insomnia.

Support

Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA

0488 Pilot Evaluation of an Actigraphy Watch Compared to Polysomnography in a Clinical Trial of Suvorexant for Treating Insomnia in Patients with Alzheimer’s Disease

Introduction

Suvorexant, an orexin receptor antagonist, improved total sleep time (TST) in a sleep laboratory polysomnography (PSG) study of patients with Alzheimer’s disease (AD) and insomnia. The study included a pilot evaluation of an actigraphy watch for continuously recording patient’s sleep and daytime activity. We report on the utility of the watch for assessing sleep in relation to gold-standard PSG.

Methods

This was a randomized, double-blind, 4-week trial (ClinicalTrials.gov NCT02750306). Participants who met diagnostic criteria for both probable AD dementia and insomnia were randomized to suvorexant 10-20mg or placebo. Overnight sleep laboratory PSG was performed on 3 nights: screening, baseline, and Night-29 (last dose). An actigraphy watch (Garmin vívosmart® HR) was worn continuously by the patient. Separate analyses were performed for PSG and watch. We compared treatment effects on change-from-baseline in PSG-TST at Night-29 and WATCH-TST at Week-4 (average TST per night over Week-4). We also analyzed Night-29 data only with watch data restricted to the PSG recording time.

Results

A total of 274 participants were included in the Night-29 PSG analysis (suvorexant=135, placebo=139) and 223 in the Week-4 watch analysis (suvorexant=113, placebo=110). Suvorexant improved Night-29 PSG-TST by 28 minutes versus placebo (p=0.001) and Week-4 WATCH-TST by 17 minutes versus placebo (p=0.144). In the subgroup who had usable data for both assessments at Night-29 (suvorexant=57, placebo=50), the watch overestimated TST compared to PSG (e.g. placebo baseline scores = 412 minutes for WATCH-TST and 265 minutes for PSG-TST) and underestimated change-from-baseline treatment effects: the suvorexant versus placebo difference was 35 minutes for PSG-TST (p=0.057) and 20 minutes for WATCH-TST (p=0.405).

Conclusion

The watch was less sensitive than PSG for evaluating treatment effects on TST. However, results obtained with the watch were directionally similar to PSG in indicating a benefit of suvorexant versus placebo for improving TST in AD patients with insomnia.

Support

Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., Kenilworth, NJ, USA

Polysomnographic assessment of suvorexant in patients with probable Alzheimer's disease dementia and insomnia: a randomized trial

Introduction

We evaluated the clinical profile of the orexin receptor antagonist suvorexant for treating insomnia in patients with mild‐to‐moderate probable Alzheimer's disease (AD) dementia.

Methods

Randomized, double‐blind, 4‐week trial of suvorexant 10 mg (could be increased to 20 mg based on clinical response) or placebo in patients who met clinical diagnostic criteria for both probable AD dementia and insomnia. Sleep was assessed by overnight polysomnography in a sleep laboratory. The primary endpoint was change‐from‐baseline in polysomnography‐derived total sleep time (TST) at week 4.

Results

Of 285 participants randomized (suvorexant, N = 142; placebo, N = 143), 277 (97%) completed the trial (suvorexant, N = 136; placebo, N = 141). At week 4, the model‐based least squares mean improvement‐from‐baseline in TST was 73 minutes for suvorexant and 45 minutes for placebo; (difference = 28 minutes [95% confidence interval 11‐45], p < 0.01). Somnolence was reported in 4.2% of suvorexant‐treated patients and 1.4% of placebo‐treated patients.

Discussion

Suvorexant improved TST in patients with probable AD dementia and insomnia.

Further analyses of the safety of verubecestat in the phase 3 EPOCH trial of mild-to-moderate Alzheimer's disease

BACKGROUND

Verubecestat, a BACE1 inhibitor that reduces Aβ levels in the cerebrospinal fluid of humans, was not effective in a phase 3 trial (EPOCH) of mild-to-moderate AD and was associated with adverse events. To assist in the development of BACE1 inhibitors, we report detailed safety findings from EPOCH.

METHODS

EPOCH was a randomized, double-blind, placebo-controlled 78-week trial evaluating verubecestat 12 mg and 40 mg in participants with mild-to-moderate AD diagnosed clinically. The trial was terminated due to futility close to its scheduled completion. Of 1957 participants who were randomized and took treatment, 652 were assigned to verubecestat 12 mg, 652 to verubecestat 40 mg, and 653 to placebo. Adverse events and relevant laboratory, vital sign, and ECG findings were assessed.

RESULTS

Verubecestat 12 mg and 40 mg were associated with an increase in the percentage of participants reporting adverse events versus placebo (89 and 92% vs. 82%), although relatively few participants discontinued treatment due to adverse events (8 and 9% vs. 6%). Adverse events that were increased versus placebo included falls and injuries, suicidal ideation, weight loss, sleep disturbance, rash, and hair color change. Most were mild to moderate in severity. Treatment differences in suicidal ideation emerged within the first 3 months but did not appear to increase after 6 months. In contrast, treatment differences in falls and injuries continued to increase over time.

CONCLUSIONS

Verubecestat was associated with increased risk for several types of adverse events. Falls and injuries were notable for progressive increases over time. While the mechanisms underlying the increased adverse events are unclear, they may be due to BACE inhibition and should be considered in future clinical development programs of BACE1 inhibitors.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01739348 , registered on 29 November 2012.

Insight Into Reduction of Wakefulness by Suvorexant in Patients With Insomnia: Analysis of Wake Bouts

Study Objectives

To examine the duration and frequency of wake bouts underlying the wakefulness-after-sleep-onset (WASO) reduction with suvorexant.

Methods

We analyzed polysomnogram recordings from clinical trials involving 1518 insomnia patients receiving suvorexant (40/30, 20/15 mg) or placebo to determine the following: (1) the number of, and time spent in, long or short wake bouts and (2) the association between sleep quality and bout characteristics. We also compared wake and sleep bout characteristics of suvorexant in insomnia patients versus zolpidem in healthy subjects undergoing experimentally induced transient insomnia.

Results

Relative to placebo, suvorexant decreased the number and time spent in long wake bouts (>2 minutes) and increased the number and time spent in short wake bouts (≤2 minutes). The time spent in long wake bouts during Night-1 decreased by 32-54 minutes, whereas the time spent in short wake bouts increased by 2-6 minutes. On average, a patient returned to sleep from his or her longest awakening more than twice as fast on suvorexant than placebo. The reduced time spent in long wake bouts resulted in odds ratios of self-reported good or excellent sleep quality ranging from 1.59 to 2.19 versus placebo. The small increase in time spent in short wake bouts had no effect on odds ratios. Findings were more pronounced for the higher (40/30 mg) doses of suvorexant. The wake and sleep bout characteristics of suvorexant differed from zolpidem which equally decreased the number of wake and sleep bouts of all durations during the early part of the night.

Conclusion

Suvorexant reduces WASO by reducing long wake bouts. This reduction has a positive effect on sleep quality.

Clinical Trials

Trial registration at www.clinicaltrials.gov NCT01097616; NCT01097629.

Suvorexant in Elderly Patients with Insomnia: Pooled Analyses of Data from Phase III Randomized Controlled Clinical Trials

OBJECTIVE

Suvorexant is an orexin receptor antagonist approved for treating insomnia at doses of 10-20 mg. Previously reported phase III results showed that suvorexant was effective and well-tolerated in a combined-age population (elderly and nonelderly adults). The present analysis evaluated the clinical profile of suvorexant specifically in the elderly.

METHODS

Prespecified subgroup analyses of pooled 3-month data from two (efficacy) and three (safety) randomized, double-blind, placebo-controlled, parallel-group trials. In each trial, elderly (≥65 years) patients with insomnia were randomized to suvorexant 30 mg, suvorexant 15 mg, and placebo. By design, fewer patients were randomized to 15 mg. Patient-reported and polysomnographic (subset of patients) sleep maintenance and onset endpoints were measured.

RESULTS

Suvorexant 30 mg (N = 319) was effective compared with placebo (N = 318) on patient-reported and polysomnographic sleep maintenance, and onset endpoints at Night 1 (polysomnographic endpoints)/Week 1 (patient-reported endpoints), Month 1, and Month 3. Suvorexant 15 mg (N = 202 treated) was also effective across these measures, although the onset effect was less evident at later time points. The percentages of patients discontinuing because of adverse events over 3 months were 6.4% for 30 mg (N = 627 treated), 3.5% for 15 mg (N = 202 treated), and 5.5% for placebo (N = 469 treated). Somnolence was the most common adverse event (8.8% for 30 mg, 5.4% for 15 mg, 3.2% for placebo).

CONCLUSION

Suvorexant generally improved sleep maintenance and onset over 3 months of nightly treatment and was well-tolerated in elderly patients with insomnia (clinicaltrials.gov; NCT01097616, NCT01097629, NCT01021813).

Phase II Proof-of-Concept Trial of the Orexin Receptor Antagonist Filorexant (MK-6096) in Patients with Major Depressive Disorder

BACKGROUND

We evaluated the orexin receptor antagonist filorexant (MK-6096) for treatment augmentation in patients with major depressive disorder.

METHODS

We conducted a 6-week, double-blind, placebo-controlled, parallel-group, Phase II, proof-of-concept study. Patients with major depressive disorder (partial responders to ongoing antidepressant therapy) were randomized 1:1 to once-daily oral filorexant 10 mg or matching placebo.

RESULTS

Due to enrollment challenges, the study was terminated early, resulting in insufficient statistical power to detect a prespecified treatment difference; of 326 patients planned, 129 (40%) were randomized and 128 took treatment. There was no statistically significant difference in the primary endpoint of change from baseline to week 6 in Montgomery Asberg Depression Rating Scale total score; the estimated treatment difference for filorexant-placebo was -0.7 (with negative values favoring filorexant) (P=.679). The most common adverse events were somnolence and suicidal ideation.

CONCLUSIONS

The interpretation of the results is limited by the enrollment, which was less than originally planned, but the available data do not suggest efficacy of orexin receptor antagonism with filorexant for the treatment of depression. (Clinical Trial Registry: clinicaltrials.gov: NCT01554176).

Clinical profile of suvorexant for the treatment of insomnia over 3 months in women and men: subgroup analysis of pooled phase-3 data

RATIONALE

Sex-related differences in the clinical profiles of some insomnia medications have been previously reported.

OBJECTIVE

To evaluate the clinical profile of suvorexant, a novel orexin receptor antagonist approved for treating insomnia at doses up to 20 mg, by sex subgroups.

METHODS

Efficacy analyses by sex were based on pooled data from two similar phase 3, randomized, double-blind, placebo-controlled, 3-month trials in elderly (≥65 years) and non-elderly (18-64 years) insomnia patients. Two age-adjusted (non-elderly/elderly) dose regimes of 40/30 and 20/15 mg were evaluated, with fewer patients assigned to 20/15 mg. Efficacy was assessed by patient-reported outcomes (N = 1264 women, 707 men) and by polysomnography endpoints in ~75% of patients. Safety analyses by sex (N = 1744 women, 1065 men) included pooled data from the two 3-month trials plus 3-month data from a safety trial of 40/30 mg.

RESULTS

The sex subgroup efficacy analyses mirrored the improvements seen for suvorexant 40/30 and 20/15 mg over placebo on patient-reported outcomes and polysomnography sleep maintenance and onset endpoints in the primary analyses; 95% CIs excluded zero in favor of suvorexant for most endpoints in both sexes, and similar efficacy was observed between sexes (95% CIs overlapped). Suvorexant was well-tolerated in women and men, although women in all treatment groups (including placebo) reported more adverse events than men. The most frequent adverse event was somnolence (women: 11.1% for 40/30 mg, 8.5% for 20/15 mg, 2.3% for placebo; men: 10.1% for 40/30 mg, 3.4% for 20/15 mg, 4.2% for placebo).

CONCLUSION

Suvorexant was generally effective and well-tolerated in both women and men with insomnia. ClinicalTrials.gov trial registration numbers: NCT01097616, NCT01097629, NCT01021813.

Randomized trial of preladenant, given as monotherapy, in patients with early Parkinson disease

Objective:

To evaluate the adenosine 2a receptor antagonist preladenant as a nondopaminergic drug for the treatment of Parkinson disease (PD) when given as monotherapy.

Methods:

This was a randomized, 26-week, placebo- and active-controlled, parallel-group, multicenter, double-blind trial conducted in adults diagnosed with PD for <5 years who were not yet receiving l-dopa or dopamine agonists. Patients with a Unified Parkinson’s Disease Rating Scale (UPDRS) part 3 (motor function) score ≥10 and Hoehn & Yahr score ≤3 were randomized 1:1:1:1:1 to preladenant 2, 5, or 10 mg twice daily, rasagiline 1 mg (active-control) once daily, or placebo. The primary endpoint was the change from baseline at week 26 in the sum of UPDRS parts 2 (activities of daily living) and 3 scores (UPDRS2+3).

Results:

The number of patients treated was 1,007. Neither preladenant nor rasagiline was superior to placebo after 26 weeks. The differences vs placebo (95% confidence interval) in UPDRS2+3 scores (with a negative difference indicating improvement vs placebo) were preladenant 2 mg = 2.60 (0.86, 4.30), preladenant 5 mg = 1.30 (−0.41, 2.94), preladenant 10 mg = 0.40 (−1.29, 2.11), and rasagiline 1 mg = 0.30 (−1.35, 2.03). Post hoc analyses did not identify a single causal factor that could explain the finding of a failed trial. Preladenant was generally well-tolerated with few patients discontinuing due to adverse events (preladenant 7%, rasagiline 3%, placebo 4%).

Conclusions:

No evidence supporting the efficacy of preladenant as monotherapy was observed in this phase 3 trial. The lack of efficacy of the active control rasagiline makes it difficult to interpret the results.

Clinical trial registration:

Clinicaltrials.gov: NCT01155479.

Classification of evidence:

This study provides Class I evidence that for patients with early PD, preladenant is not effective as monotherapy at the doses studied (2, 5, 10 mg).

EEG spectral analysis of NREM sleep in a large sample of patients with insomnia and good sleepers: effects of age, sex and part of the night

Previous studies of the differences between patients with insomnia and good sleepers with regard to quantitative electroencephalographic measures have mostly utilized small samples and consequently had limited ability to account for potentially important confounding factors of age, sex and part of the night. We conducted a power spectral analysis using a large database of sleep electroencephalographic recordings to evaluate differences between patients with insomnia (N = 803) and good sleepers (N = 811), while simultaneously accounting for these factors and their interaction. Comparisons of power as a function of age and part of the night were made between cohorts (patients with insomnia versus good sleepers) by sex. Absolute power in the delta, theta and sigma bands declined with age for both females and males. Females had significantly greater power than males at all ages, and for each band, cohort and part of the night. These sex differences were much greater than differences between patients with insomnia and good sleepers. Compared with good sleepers, patients with insomnia under age 40-45 years had reduced delta band power during Part 1 of the night. Females with insomnia over age 45 years had increased delta and theta band power in Parts 2 and 3 of the night, and males with insomnia under age 40 years had reduced theta power in Part 1. Females with insomnia had increased beta2 power in all parts of the night, and males with insomnia had reduced alpha power during all parts of the night. Relative power (the proportion that an individual frequency band contributes to the total power) decreased in the delta band and increased in all other bands with age for both cohorts, sexes and all parts of the night. This analysis provides a unique resource for quantitative information on the differences in power spectra between patients with insomnia and good sleepers accounting for age, sex and part of the night.

Suvorexant in Patients with Insomnia: Pooled Analyses of Three-Month Data from Phase-3 Randomized Controlled Clinical Trials

STUDY OBJECTIVES

Suvorexant is an orexin receptor antagonist approved for treating insomnia at a maximum dose of 20 mg. Phase-3 trials evaluated two age-adjusted (non-elderly/elderly) dose-regimes of 40/30 mg and 20/15 mg with the primary focus on 40/30 mg. We report here results from pooled analyses of the 20/15 mg dose-regime, which was evaluated as a secondary objective in the trials.

METHODS

Prespecified analysis of pooled data from two identical randomized, double-blind, placebo-controlled, parallel-group, 3-month trials in non-elderly (18-64 years) and elderly (≥ 65 years) patients with insomnia. Patients were randomized to suvorexant 20/15 mg (non-elderly/elderly), suvorexant 40/30 mg (non-elderly/elderly), or placebo; by design, fewer patients were randomized to 20/15 mg. Efficacy was assessed by self-reported and polysomnography (PSG; subset of patients) sleep maintenance and onset endpoints.

RESULTS

Suvorexant 20/15 mg (N = 493 treated) was effective compared to placebo (N = 767 treated) on patient-reported and PSG sleep maintenance and onset endpoints at Night-1 (PSG endpoints) / Week-1 (subjective endpoints), Month-1 and Month-3, except for effects on PSG sleep onset at Month-3. Suvorexant 20/15 mg was generally well tolerated, with 3% of patients discontinuing due to adverse events over 3 months vs. 5.2% on placebo. Somnolence was the most common adverse event (6.7% vs. 3.3% for placebo). There was no systematic evidence of rebound or withdrawal signs or symptoms when suvorexant was discontinued after 3 months of nightly use.

CONCLUSIONS

Suvorexant 20/15 mg improved sleep onset and maintenance over 3 months of nightly treatment and was generally safe and well tolerated.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov trial registration numbers: NCT01097616, NCT01097629.

Suvorexant in Patients With Insomnia: Results From Two 3-Month Randomized Controlled Clinical Trials

BACKGROUND

Suvorexant is an orexin receptor antagonist for treatment of insomnia. We report results from two pivotal phase 3 trials.

METHODS

Two randomized, double-blind, placebo-controlled, parallel-group, 3-month trials in nonelderly (18-64 years) and elderly (≥65 years) patients with insomnia. Suvorexant doses of 40/30 mg (nonelderly/elderly) and 20/15 mg (nonelderly/elderly) were evaluated. The primary focus was 40/30 mg, with fewer patients randomized to 20/15 mg. There was an optional 3-month double-blind extension in trial 1. Each trial included a 1-week, randomized, double-blind run-out after double-blind treatment to assess withdrawal/rebound. Efficacy was assessed at week 1, month 1, and month 3 by patient-reported subjective total sleep time and time to sleep onset and in a subset of patients at night 1, month 1, and month 3 by polysomnography end points of wakefulness after persistent sleep onset and latency to onset of persistent sleep (LPS). One thousand twenty-one patients were randomized in trial 1 and 1019 patients in trial 2.

RESULTS

Suvorexant 40/30 mg was superior to placebo on all subjective and polysomnography end points at night 1/week 1, month 1, and month 3 in both trials, except for LPS at month 3 in trial 2. Suvorexant 20/15 mg was superior to placebo on subjective total sleep time and wakefulness after persistent sleep onset at night 1/week 1, month 1, and month 3 in both trials and at most individual time points for subjective time to sleep onset and LPS in each trial. Both doses of suvorexant were generally well tolerated, with <5% of patients discontinuing due to adverse events over 3 months. The results did not suggest the emergence of marked rebound or withdrawal signs or symptoms when suvorexant was discontinued.

CONCLUSIONS

Suvorexant improved sleep onset and maintenance over 3 months of nightly treatment and was generally safe and well tolerated.

Effects of Suvorexant, an Orexin Receptor Antagonist, on Respiration during Sleep In Patients with Obstructive Sleep Apnea

STUDY OBJECTIVES

To investigate the respiratory effects of suvorexant, an orexin receptor antagonist for treating insomnia, in patients with obstructive sleep apnea (OSA).

METHODS

This was a randomized, double-blind, placebo-controlled, 2-period (4 days per period), crossover, sleep laboratory study. Twenty-six patients aged 18-65 years with mild (apnea-hypopnea index [AHI] ≥ 5 and < 15) to moderate (AHI ≥ 15 and < 30) OSA were randomized to receive suvorexant 40 mg or placebo in period-1 and then crossed over to the other treatment in period-2. Breathing during sleep was measured by AHI (primary endpoint) and oxygen saturation assessed by pulse oximetry (SpO2, secondary endpoint). The study was powered to rule out a mean increase in AHI between suvorexant and placebo of 5 or greater on Day 4.

RESULTS

There was a small increase in mean AHI (2.66) in OSA patients after multiple doses of suvorexant relative to placebo, with the upper 90% CI bound slightly exceeding 5.00 (0.22, 5.09). No increase in mean AHI was observed after a single dose of suvorexant versus placebo (mean difference = -0.47 [-3.20, 2.26]), and there was no treatment effect on mean SpO2 during total sleep time after single or multiple doses (Day 1: mean difference = -0.04 [-0.49, 0.42]; Day 4: mean difference = -0.06 [-0.45, 0.33]). There was inter- and intra-individual variability in suvorexant respiratory effects.

CONCLUSIONS

Suvorexant 40 mg, twice the 20 mg maximum recommended dose for treating insomnia in the USA and Japan, does not appear to have clinically important respiratory effects during sleep in patients with mild to moderate OSA as assessed by mean AHI and SpO2. Due to inter- and intra-individual variability in respiratory effects, suvorexant should be used with caution in patients with compromised respiratory function, and at the lowest effective dose.

CLINICAL TRIAL REGISTRATION

clinicaltrials.gov, NCT01300455.

Effects of suvorexant on sleep architecture and power spectral profile in patients with insomnia: analysis of pooled phase 3 data

BACKGROUND

The orexin receptor antagonist, suvorexant, is approved for treating insomnia at a maximum dose of 20 mg. We evaluated its effects on sleep architecture.

METHODS

The analyses included pooled polysomnography data from two similar randomized, double-blind, placebo-controlled, 3-month trials evaluating two age-adjusted (non-elderly/elderly) dose regimes of 20/15 mg and 40/30 mg in 1482 patients with insomnia. Polysomnography was recorded at baseline and on three nights during the treatment: Night-1, Month-1, and Month-3. Effects on non-REM sleep stages 1 (N1), 2 (N2), 3 (N3)/slow wave sleep (SWS), and REM sleep were evaluated. A power spectral analysis of non-REM sleep was also performed.

RESULTS

Suvorexant increased the time (in minutes) spent in all sleep stages compared with placebo. When suvorexant and placebo were compared in terms of changes in percentage of total sleep time spent in each stage, there were small decreases of ≤1%, ≤2.2%, and ≤0.8% for N1, N2, and N3/SWS on average, respectively, and an average increase of ≤3.9% in REM. The largest differences from placebo were observed at Night-1 and generally diminished over time. Suvorexant reduced REM latency (number of non-REM 30-s epochs from lights-off to the first REM epoch) compared with placebo; the reduction was greater at Night-1 (~40-50 non-REM epochs) in comparison to later time points (~12-25 non-REM epochs at Month-3). The spectral analysis of non-REM showed a small decrease in power of 3-6% in the gamma and beta bands, and a small increase of 4-8% in the delta band, at Night-1 for suvorexant relative to placebo; these effects were not apparent at the later Month-1 and Month-3 time points.

CONCLUSION

Overall sleep architecture appears to be preserved in insomnia patients taking suvorexant. The power spectral profile of suvorexant is generally similar to placebo.

Effects of the orexin receptor antagonist suvorexant on respiration during sleep in healthy subjects

Suvorexant is an orexin receptor antagonist for treating insomnia. The maximum approved dose in the United States and Japan is 20 mg. We evaluated suvorexant effects on respiration during sleep in a randomized, double-blind, 3-period crossover study of healthy adult men (n = 8) and women (n = 4) ≤ 50 years old who received single-dose suvorexant 40 mg, 150 mg, and placebo. Respiration during sleep was measured by oxygen saturation (SpO2 , primary end point) and the Apnea Hypopnea Index (AHI). The study was powered to detect a reduction greater than 5% in SpO2 . There was no effect of suvorexant on mean SpO2 during sleep. The mean (90%CI) treatment differences versus placebo were -0.3 (-1.2-0.6) for 40 mg and 0.0 (-0.9-0.9) for 150 mg. There were no dose-related trends in individual SpO2 values. Mean SpO2 was >96% for all treatments during total sleep time and during both non-REM and REM sleep. There was no effect of either suvorexant dose on AHI. The mean (90%CI) treatment differences versus placebo were 0.8 (-0.7-2.3) for 40 mg and -0.2 (-1.7-1.3) for 150 mg. Suvorexant was generally well tolerated; there were no serious adverse experiences or discontinuations. These data from healthy subjects suggest that suvorexant lacks clinically important respiratory effects during sleep at doses greater than the maximum recommended dose for treating insomnia.

Randomized controlled trial of the CGRP receptor antagonist telcagepant for prevention of headache in women with perimenstrual migraine

Aim

The aim of this article is to evaluate the safety and efficacy of perimenstrual telcagepant, a CGRP receptor antagonist, for headache prophylaxis.

Methods

We conducted a randomized, double-blind, placebo-controlled, six-month trial in women with migraine for ≥3 months who experienced perimenstrual headaches. Women were randomized to telcagepant 140 mg or placebo (2:1 ratio) for seven consecutive days perimenstrually. Safety was assessed by adverse events and laboratory tests. The primary efficacy endpoint was mean monthly headache days in the subset of women reporting perimenstrual migraine (−2 days to +3 days of menses onset) and ≥5 moderate or severe migraines per month prior to entering the trial.

Results

Telcagepant was generally well tolerated: 66/2660 (2.5%) on telcagepant and 36/1326 (2.7%) on placebo discontinued because of a clinical adverse event. The percentages of patients with clinical adverse events, laboratory adverse events, or discontinuation because of a laboratory adverse event were also similar between treatments. Alanine aminotransferase elevations ≥3× normal occurred in 0.6% of women on telcagepant and 0.4% on placebo. Three women on telcagepant vs none on placebo had alanine aminotransferase elevations ≥8× normal. In the efficacy subset there was no significant effect of telcagepant ( n = 887) vs placebo ( n = 447) in mean monthly headache days (treatment difference −0.5 day (95% CI: −1.1, 0.1)). However, telcagepant was associated with a reduction in on-drug headache days (treatment difference −0.4 day (95% CI: –0.5, –0.2), nominal p < 0.001).

Conclusions

Telcagepant 140 mg taken perimenstrually for seven days was generally well tolerated, but was associated with transaminase elevations . Telcagepant did not reduce monthly headache frequency, but did reduce perimenstrual headaches.

Addition of an NK1 receptor antagonist to an SSRI did not enhance the antidepressant effects of SSRI monotherapy: results from a randomized clinical trial in patients with major depressive disorder

OBJECTIVE

Aprepitant is a neurokinin 1 receptor antagonist approved for prevention of chemotherapy-induced and post-operative nausea and vomiting. Early studies demonstrated promising antidepressant activity as monotherapy, although this was unsupported by subsequent phase 3 trials. This phase 2 study evaluated whether aprepitant potentiated the antidepressant effects of paroxetine.

METHODS

Outpatients with major depressive disorder were randomized to aprepitant 200 mg + paroxetine 20 mg, paroxetine + placebo, or aprepitant + placebo for 6 weeks. The primary endpoint was change in HAMD-17 total score. Secondary/exploratory endpoints included changes in HAMA, CGI-S, CGI-I, and HAMD Item-1 scores at week 6.

RESULTS

A total of 79, 78, and 79 patients received aprepitant + paroxetine, paroxetine + placebo, and aprepitant + placebo, respectively. At week 6, mean changes in HAMD-17 were -11.0 (95% confidence interval [CI]: -12.7, -9.4), -11.7 (95% CI: -13.3, -10.0), and -9.5 (95% CI: -10.9, -8.1), respectively. Pairwise comparisons of HAMD-17 change with combination therapy versus paroxetine alone demonstrated no significant difference (p = 0.567). Changes in CGI-S, CGI-I, and HAMD Item-1 scores were also comparable, although there was a greater reduction in anxiety (HAMA) with paroxetine alone than aprepitant + paroxetine (p = 0.045). Adverse events were generally more common with the combination than either monotherapy.

CONCLUSION

Concomitant use of aprepitant + paroxetine for 6 weeks did not provide greater antidepressant benefit compared with paroxetine + placebo in patients with major depression.

Electroencephalographic power spectral density profile of the orexin receptor antagonist suvorexant in patients with primary insomnia and healthy subjects

STUDY OBJECTIVES

Suvorexant, an orexin receptor antagonist, improves sleep in healthy subjects (HS) and patients with insomnia. We compared the electroencephalographic (EEG) power spectral density (PSD) profile of suvorexant with placebo using data from a phase 2 trial in patients with insomnia. We also compared suvorexant's PSD profile with the profiles of other insomnia treatments using data from 3 HS studies.

DESIGN

Phase 2 trial--randomized, double-blind, two-period (4 w per period) crossover. HS studies--randomized, double-blind, crossover.

SETTING

Sleep laboratories.

PARTICIPANTS

Insomnia patients (n = 229) or HS (n = 124).

INTERVENTIONS

Phase 2 trial--suvorexant 10 mg, 20 mg, 40 mg, 80 mg, placebo; HS study 1--suvorexant 10 mg, 50 mg, placebo; HS study 2--gaboxadol 15 mg, zolpidem 10 mg, placebo; HS study 3--trazodone 150 mg, placebo.

MEASUREMENTS AND RESULTS

The PSD of the EEG signal at 1-32 Hz of each PSG recording during nonrapid eye movement (NREM) and rapid eye movement (REM) sleep were calculated. The day 1 and day 28 PSD profiles of suvorexant at all four doses during NREM and REM sleep in patients with insomnia were generally flat and close to 1.0 (placebo) at all frequencies. The day 1 PSD profile of suvorexant in HS was similar to that in insomnia patients. In contrast, the other three drugs had distinct PSD profiles in HS that differed from each other.

CONCLUSIONS

Suvorexant at clinically effective doses had limited effects on power spectral density compared with placebo in healthy subjects and in patients with insomnia, in contrast to the three comparison insomnia treatments. These findings suggest the possibility that antagonism of the orexin pathway might lead to improvements in sleep without major changes in the patient's neurophysiology as assessed by electroencephalographic.

Randomized controlled trial of the orexin receptor antagonist filorexant for migraine prophylaxis

BACKGROUND

This study explored whether antagonism of orexin receptors might be an effective mechanism for migraine prevention.

METHODS

We conducted a randomized, double-blind, placebo-controlled, pilot trial. Patients experiencing four to 14 days with migraine during a one-month baseline period were randomized to the orexin receptor antagonist filorexant 10 mg nightly or placebo for three months. Efficacy was assessed by mean monthly migraine days (headache plus at least one associated migraine symptom) and headache days. Safety and tolerability were assessed by adverse event reports and laboratory tests.

RESULTS

Of 120 patients treated with filorexant and 115 treated with placebo, 97 (81%) and 101 (88%), respectively, completed the trial. There was no statistically significant difference between treatments for change from baseline in mean monthly migraine days (filorexant = -1.7, placebo = -1.3, difference = -0.4 (95% CI: -1.3, 0.4)) or headache days (filorexant = -1.7, placebo = -1.2, difference = -0.5 (95% CI: -1.4, 0.4)). Filorexant was generally well tolerated but was associated with a higher proportion of patients who reported adverse events than placebo (47% vs 37%), particularly somnolence (13% vs 4%).

CONCLUSIONS

These data fail to provide evidence that antagonism of orexin receptors with filorexant, when administered at night, is effective for migraine prophylaxis.

Randomized controlled trial of the CGRP receptor antagonist telcagepant for migraine prevention

OBJECTIVE

To evaluate whether the calcitonin gene-related peptide (CGRP) receptor antagonist telcagepant might be effective for migraine prevention.

METHODS

In this randomized, double-blind, placebo-controlled, multicenter trial (ClinicalTrials.gov NCT00797667), patients experiencing 3-14 migraine days during a 4-week baseline were randomized to telcagepant 140 mg, telcagepant 280 mg, or placebo twice daily for 12 weeks. Efficacy was assessed by mean monthly headache days and migraine/probable migraine days (headache plus ≥ 1 associated symptom).

RESULTS

The trial was terminated following a recommendation from the Safety Monitoring Board due to hepatotoxicity concerns. At termination, the planned 660 patients had been randomized, 656 had been treated with ≥ 1 dose of study medication, and 14 had completed the trial. The mean treatment duration was 48-50 days. Thirteen patients, all in the telcagepant groups, had an alanine aminotransferase (ALT) elevation ≥ 3 × the upper limit of normal and 7 of these also had an aspartate aminotransferase elevation ≥ 3 × the upper limit of normal. Two patients had very high symptomatic transaminase elevations that occurred within 2-6 weeks of treatment initiation and resolved after treatment discontinuation. The originally planned efficacy analysis over 12 weeks was not performed due to limited data at later time points, but there was evidence that telcagepant resulted in a larger reduction from baseline than placebo for mean monthly headache days (month 1: 140 mg = -2.9, 280 mg = -3.1, placebo = -1.7; p < 0.05) and migraine/probable migraine days (month 1: 140 mg = -2.7, 280 mg = -3.0, placebo = -1.6; p < 0.05).

CONCLUSIONS

These data suggest a potential role for CGRP receptor antagonism in migraine prophylaxis. However, the observed aminotransferase elevations do not support the use of telcagepant for daily administration.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that in patients with migraine, telcagepant taken daily reduces headache days by 1.4 days per month compared to placebo and causes 2.5% of patients to have elevations of serum ALT levels.

Neuropsychological investigation of anterior and posterior cortical function in early-stage probable Alzheimer's disease

In vivo neuroimaging studies have generally indicated a greater involvement of posterior cortical areas in early-stage dementia of the Alzheimer type (DAT) relative to frontal involvement. By contrast, some recent neuropsychological studies have shown that DAT patients perform poorly in frontal lobe tasks even in the early stages of the disease, although there is disagreement as to whether this necessarily implicates frontal pathology. The main aim of this study was to examine the hypothesis prompted by both neuroimaging studies and the traditional clinical conception of the disease, that, compared with the functioning of posterior association cortex, executive functions (thought to depend on frontal lobe integrity) are relatively spared in the early stages of DAT. A group of patients with a diagnosis of early-stage, probable DAT (n = 17) was compared with age- and IQ-matched controls (n = 17) across a range of neuropsychological tasks presumed to exercise frontal or temporoparietal functions. A profile of strengths and weaknesses was observed across 'anterior' and 'posterior' cognitive tests, including dissociations among some tests of temporoparietal function, in particular visual object perception (impaired) and spatial analysis skills (intact). Thus there was little support for the notion that the disease progresses cortically in a posterior-to-anterior direction. Possible reasons for the discrepancy between neurophysiological and neuropsychological observations are discussed, including the possibility that neuropsychological tests do not provide a valid indication of regional brain function when used in the context of DAT. Caution is urged in the clinical application of 'frontal lobe tests' for the differential diagnosis of DAT.

Randomized controlled study of telcagepant plus ibuprofen or acetaminophen in migraine

OBJECTIVE

To evaluate the efficacy and tolerability of telcagepant when co-administered with ibuprofen or acetaminophen for the acute treatment of migraine.

BACKGROUND

Telcagepant is an oral calcitonin gene-related peptide receptor antagonist which is being evaluated for the acute treatment of migraine. Combining telcagepant with analgesics that have a different mechanism of action could produce greater efficacy.

METHODS

Randomized, double-blind, placebo-controlled study. Patients were randomized to treat a moderate or severe migraine headache with either telcagepant 280 mg + ibuprofen 400 mg (N = 171), telcagepant 280 mg + acetaminophen 1000 mg (N = 171), telcagepant 280 mg (N =170), or placebo (N = 171). The primary efficacy endpoint was 2-hour pain freedom. The study had approximately 88% power to detect an additive effect of at least 15 percentage points (telcagepant combination vs telcagepant monotherapy) and 48% power to detect an additive effect of at least 10 percentage points. Safety and tolerability were assessed by adverse events and laboratory tests.

RESULTS

The percentages of patients with 2-hour pain freedom were greater in each active treatment group compared to placebo (P < .001): telcagepant + ibuprofen = 35.2%, telcagepant + acetaminophen = 38.3%, telcagepant = 31.2%, placebo = 10.9%. No significant differences were seen for either of the combination groups vs telcagepant monotherapy, but both were numerically larger than telcagepant monotherapy. All the active treatments were generally well tolerated. The percentage of patients reporting any adverse event within 48 hours was higher in the active treatment groups than placebo: telcagepant + ibuprofen = 30.3%, telcagepant + acetaminophen = 31.6%, telcagepant = 24.8%, placebo = 18.2%. The most common adverse events reported by ≥ 4 patients in one or more of the treatment groups that included telcagepant were fatigue, nausea, dizziness, somnolence, dry mouth, and tremor.

CONCLUSIONS

The combination of telcagepant 280 mg with either ibuprofen 400 mg or acetaminophen 1000 mg did not show a statistically significant difference from telcagepant alone. Numerically greater treatment effects in the combination treatment groups over the telcagepant 280 mg monotherapy suggest that telcagepant combination treatments may merit further evaluation in studies powered to detect smaller additive benefits. (Clinicaltrials.gov; NCT00758836).

Randomized crossover study of the histamine H3 inverse agonist MK-0249 for the treatment of cognitive impairment in patients with schizophrenia

BACKGROUND

Current antipsychotic treatments have little impact on the cognitive deficits associated with schizophrenia. It has been proposed that agents which promote histamine release may enhance cognition. We evaluated whether the H3 inverse agonist MK-0249 might improve cognitive deficits in patients with schizophrenia.

METHODS

Outpatients (N=55) with schizophrenia between ages 21 and 55 who were clinically stable, experienced no more than mild to moderate overall symptoms (PANSS score total 36-75), and were taking a stable dose of antipsychotic medication were randomized to MK-0249 10mg and placebo in a multi-center, randomized, double-blind, 2-period (4-weeks per period), cross-over study. The primary efficacy endpoint was the mean change from baseline at 4-weeks of treatment in the total cognitive score on the Brief Assessment of Cognition in Schizophrenia (BACS) Battery. Other assessments of cognition were also performed.

RESULTS

A total of 46 patients completed the study. MK-0249 10mg did not demonstrate a statistically significant difference compared to placebo in the mean change from baseline in the total cognitive score on the BACS battery after 4-weeks of treatment (-0.1, 95% CI: -2.3, 2.1) or with regard to secondary measures of attention/processing speed, episodic memory, or working memory after 4-weeks of treatment. The incidence of adverse events was greater during the MK-0249 treatment period (25/52 patients, 48.1%) compared to the placebo treatment period (15/51 patients, 29.4%).

CONCLUSION

MK-0249 10mg once daily was not superior to placebo in the treatment of cognitive impairment in patients with schizophrenia after 4-weeks. (Clinicaltrials.gov: NCT00506077).

Randomized controlled study of the T-type calcium channel antagonist MK-8998 for the treatment of acute psychosis in patients with schizophrenia

OBJECTIVE

This study aimed to evaluate whether the T-type calcium channel antagonist MK-8998 was effective in treating acute psychosis in patients with schizophrenia.

METHODS

This was a randomized, double-blind, parallel-group study. After a placebo lead-in, acutely psychotic inpatients with schizophrenia were randomized to 4 weeks of MK-8998 12/16 mg daily (N = 86), olanzapine 10/15 mg daily (N = 47), or placebo (N = 83). The primary efficacy measure was score on the Positive and Negative Syndrome Scale (PANSS).

RESULTS

Out of 216 randomized patients, 158 completed the 4-week study: MK-8998 = 58 (67.4%), olanzapine = 38 (80.9%), and placebo = 62 (74.7%). The mean changes from baseline in PANSS score at week 4 for MK-8998 and olanzapine were not significantly different from placebo: MK-8998-placebo difference = -0.6 [95% confidence interval (CI): -7.0, 5.8], p = 0.9; olanzapine-placebo difference = -4.3 [95% CI: -11.7, 3.1), p = 0.3. A responder rate analysis (≥20% improvement from baseline in PANSS score) suggested an advantage of olanzapine over placebo (odds ratio = 2.20 [95% CI: 0.95, 5.09], p = 0.07) but no effect of MK-8998 over placebo (odds ratio = 1.28 [95% CI: 0.62, 2.64], p = 0.5). Treatments were generally well tolerated, but more patients reported adverse events for MK-8998 (47.7%) and olanzapine (48.9%) than placebo (37.3%).

CONCLUSIONS

MK-8998 was not effective in treating acutely psychotic inpatients with schizophrenia, as measured by PANSS score at week 4. Because of the limited efficacy of the active comparator, we cannot exclude the possibility that T-type calcium channel antagonists could prove to be effective in schizophrenia.

Effects of suvorexant, an orexin receptor antagonist, on sleep parameters as measured by polysomnography in healthy men

STUDY OBJECTIVES

Suvorexant (MK-4305) is an orexin receptor antagonist being developed for the treatment of insomnia. This report describes the effects of nighttime administration of suvorexant on polysomnography (PSG) sleep parameters in healthy young men.

DESIGN

Randomized, double-blind, placebo-controlled, 4-period crossover PSG study, followed by an additional 5(th) period to assess pharmacokinetics.

SETTING

Sleep laboratory.

PARTICIPANTS

Healthy young men between 18 and 45 years of age (22 enrolled, 19 completed).

INTERVENTIONS

Periods 1-4: suvorexant (10 mg, 50 mg, or 100 mg) or placebo 1 h before nighttime PSG recording. Period 5: suvorexant 10 mg, 50 mg, or 100 mg.

MEASUREMENTS AND RESULTS

In Periods 1-4, overnight sleep parameters were recorded by PSG and next-morning residual effects were assessed by psychomotor performance tests and subjective assessments. Statistically significant sleep-promoting effects were observed with all doses of suvorexant compared to placebo. Suvorexant 50 mg and 100 mg significantly decreased latency to persistent sleep and wake after sleep onset time, and increased sleep efficiency. Suvorexant 10 mg significantly decreased wake after sleep onset time. There were no statistically significant effects of suvorexant on EEG frequency bands including delta (slow wave) activity based on power spectral analysis. Suvorexant was well tolerated. There was no evidence of next-day residual effects for suvorexant 10 mg. Suvorexant 50 mg statistically significantly reduced subjective alertness, and suvorexant 100 mg significantly increased reaction time and reduced subjective alertness. There were no statistically significant effects of any suvorexant dose on digit symbol substitution test performance. In Period 5, plasma samples of suvorexant were collected for pharmacokinetic evaluation. The median T(max) was 3 hours and apparent terminal t(½) was 9-13 hours.

CONCLUSIONS

In healthy young men without sleep disorders, suvorexant promoted sleep with some evidence of residual effects at the highest doses.

Orexin receptor antagonism for treatment of insomnia: a randomized clinical trial of suvorexant

OBJECTIVE

To assess the utility of orexin receptor antagonism as a novel approach to treating insomnia.

METHODS

We evaluated suvorexant, an orexin receptor antagonist, for treating patients with primary insomnia in a randomized, double-blind, placebo-controlled, 2-period (4 weeks per period) crossover polysomnography study. Patients received suvorexant (10 mg [n = 62], 20 mg [n = 61], 40 mg [n = 59], or 80 mg [n = 61]) in one period and placebo (n = 249) in the other. Polysomnography was performed on night 1 and at the end of week 4 of each period. The coprimary efficacy end points were sleep efficiency on night 1 and end of week 4. Secondary end points were wake after sleep onset and latency to persistent sleep.

RESULTS

Suvorexant showed significant (p values <0.01) dose-related improvements vs placebo on the coprimary end points of sleep efficiency at night 1 and end of week 4. Dose-related effects were also observed for sleep induction (latency to persistent sleep) and maintenance (wake after sleep onset). Suvorexant was generally well tolerated.

CONCLUSIONS

The data suggest that orexin receptor antagonism offers a novel approach to treating insomnia.

CLASSIFICATION OF EVIDENCE

This study provides Class I evidence that suvorexant improves sleep efficiency over 4 weeks in nonelderly adult patients with primary insomnia.

Long-term open-label safety study of rizatriptan acute treatment in pediatric migraineurs

OBJECTIVE

To evaluate the safety/tolerability of rizatriptan in the long-term acute treatment of migraine in pediatric patients.

BACKGROUND

Acute migraine treatment options for children are limited. A recent single-attack trial demonstrated that rizatriptan is effective in eliminating migraine headache pain in this population. We evaluated the long-term safety and efficacy of rizatriptan when used for intermittent acute treatment.

METHODS

Open-label study in pediatric migraineurs ages 12-17 years. Patients weighing <40 kg received rizatriptan (orally disintegrating tablet) 5 mg, and those weighing ≥40 kg received 10 mg. Patients could treat up to 8 mild/moderate/severe migraine attacks per month for up to 12 months. One dose of study medication was allowed in a 24-hour period.

RESULTS

A total of 674 patients were enrolled, and 606 patients were treated with study medication (N = 583 for 10 mg, N = 23 for 5 mg). The mean duration in the study was 292 days, and the mean number of doses of study medication taken was 20. Over the course of the study within 14 days post-any-dose, 66.0% (400) of the 606 treated patients had any adverse event, 2.3% (14) discontinued due to an adverse event, 2.6% (16) had a serious adverse event, and 23.4% (142) had a triptan-related adverse event. Of the 16 patients with serious adverse events within 14 days post-any-dose, the adverse events in 3 were considered drug-related; all 3 patient's adverse events were classified as serious only because they were associated with an overdose (use of >1 dose of study medication in a 24-hour period). The mean percentage of patient's attacks with pain freedom at 2-hours post-dose was 46.3%; this was relatively consistent over time (Months 1-3 = 43.7%, Months 4-6 = 51.9%, Months 7-9 = 49.9%, Months 10-12 = 49.5%).

CONCLUSION

Rizatriptan was generally safe and well tolerated in the long-term acute treatment of migraine in pediatric patients aged 12-17 years and demonstrated a consistent treatment effect over time.

Efficacy and tolerability of rizatriptan in pediatric migraineurs: Results from a randomized, double-blind, placebo-controlled trial using a novel adaptive enrichment design

Background

Treatment options for children and adolescents with migraine are limited. This study evaluated rizatriptan for the acute treatment of migraine in children and adolescents.

Methods

Randomized, double-blind, placebo-controlled, parallel-group trial in migraineurs 6–17 years old with unsatisfactory response to nonsteroidal anti-inflammatory drugs or acetaminophen/paracetamol. The trial included a double-blind run-in with weight-based rizatriptan dosing (5 mg for <40 kg, 10 mg for ≥40 kg). In the Stage 1 run-in, patients were randomized in a ratio of 20:1 placebo:rizatriptan and were instructed to treat within 30 minutes of a moderate/severe migraine. Patients with mild/no pain after 15 minutes of treatment (responders) took no further study medication, whereas patients with moderate/severe pain (non-responders) proceeded to take study medication in Stage 2. Non-responders who received placebo in Stage 1 were randomized 1:1 to rizatriptan:placebo, whereas non-responders who received rizatriptan in Stage 1 were allocated to placebo in Stage 2. The primary efficacy endpoint was pain freedom at 2 hours after Stage 2 dose in 12–17-year-olds.

Results

A higher proportion of 12–17-year-olds on rizatriptan had pain freedom at 2 hours compared with those on placebo: 87/284 (30.6%) versus 63/286 (22.0%), odds ratio = 1.55 [95% CI: 1.06 to 2.26], p = 0.025. Adverse events within 14 days of dose in 12–17-year-olds were similar for rizatriptan and placebo. The pattern of findings was similar in 6–17-year-olds.

Conclusion

Rizatriptan demonstrated a statistically significant improvement over placebo in eliminating pain and was generally well tolerated in migraineurs aged 12–17 and 6–17 years.

Trial Registration

ClinicalTrials.gov NCT01001234

Randomized, controlled study of telcagepant in patients with migraine and coronary artery disease

OBJECTIVE

To evaluate the efficacy of telcagepant in patients with migraine and coronary artery disease.

BACKGROUND

Calcitonin gene-related peptide receptor antagonists, such as telcagepant, may be useful for acute migraine treatment in patients with cardiovascular disease, a population for whom triptans are contraindicated.

METHODS

Randomized, double-blind, two-period (6 weeks per period) crossover study in patients with stable coronary artery disease and migraine. Patients were randomized 1:1 to either: (1) Period 1: telcagepant (280-mg tablet/300-mg capsule), Period 2: acetaminophen (1000-mg); or (2) Period 1: placebo for attack 1 then acetaminophen for subsequent attacks, Period 2: telcagepant. Patients could treat up to 12 migraine attacks per period to assess the tolerability of telcagepant. The primary efficacy analysis evaluated telcagepant vs placebo on 2-hour pain freedom during the first attack of Period 1.

RESULTS

One hundred and sixty-five of the planned 400 patients were enrolled, and 114 took at least one dose of treatment. Telcagepant was not statistically different from placebo for 2-hour pain freedom (25.0% vs 18.9%, odds ratio = 1.62 [95% confidence interval: 0.62, 4.25]). The median number of attacks treated per period was 3. No cardiovascular thrombotic adverse events occurred within 14 days of dosing.

CONCLUSION

The study was underpowered due to enrollment difficulties and did not demonstrate a significant efficacy difference between telcagepant and placebo for the treatment of a migraine attack in patients with stable coronary artery disease. Telcagepant was generally well tolerated for acute intermittent migraine treatment in these patients.

Additive effects of a cholinesterase inhibitor and a histamine inverse agonist on scopolamine deficits in humans

RATIONALE

Enhancement of histaminergic neurotransmission or histaminergic plus cholinergic neurotransmission may represent novel strategies for improving cognition in Alzheimer's disease.

OBJECTIVE

To evaluate the effects of a novel histamine H3 receptor inverse agonist (MK-3134), an acetylcholinesterase inhibitor (donepezil), and their combination in attenuating the cognitive impairment associated with scopolamine.

METHODS

Thirty-one subjects were randomized, and 28 completed this double-blind, placebo-controlled, five-period crossover study. Cognition was assessed using the Groton Maze Learning Task (GMLT) as the primary outcome measure. The two primary hypotheses were that donepezil 10 mg and MK-3134 25 mg, respectively, would attenuate scopolamine (0.5 mg)-induced impairment as measured by the GMLT over the first 12 h after scopolamine administration (AUC(1-12)  (h)). A secondary hypothesis was that the combination of donepezil and MK-3134 would attenuate scopolamine-induced cognitive impairment to a greater extent than either agent alone as measured by the GMLT AUC(1-12 h).

RESULTS

The primary and secondary hypotheses were not met. Upon examining the time course of the scopolamine effects (an exploratory objective), peak effects were generally observed around 2 h after scopolamine administration. Administration of MK-3134 or donepezil improved performance on the GMLT at the 2-h time point, rather than AUC(1-12 h), compared with scopolamine alone. Moreover, it appeared that the combination of MK-3134 and donepezil blunted the scopolamine effect to a greater extent than either drug alone.

CONCLUSIONS

Exploratory analyses provide evidence for cognitive improvement through inverse agonism of the H3 histamine receptor and for cooperation between human cholinergic and histaminergic neurotransmitter systems. (ClinicalTrials.gov trial registration number: NCT01181310).

Randomized controlled trial of the CGRP receptor antagonist MK-3207 in the acute treatment of migraine

Background: This study evaluated the CGRP receptor antagonist MK-3207 for acute treatment of migraine.

Methods: Multicenter, double-blind, randomized, placebo-controlled, parallel-group, two-stage adaptive study with two interim efficacy analyses to facilitate optimal dose selection. Migraine patients were initially randomized to MK-3207 2.5, 5, 10, 20, 50 and 100 mg or placebo to treat a moderate/severe migraine. One or more doses were to be discontinued based on the first interim analysis and a lower or higher dose could be added based on the second interim analysis. The primary endpoint was two-hour pain freedom.

Results: A total of 547 patients took study medication. After the first interim analysis, the two lowest MK-3207 doses (2.5, 5 mg) were identified as showing insufficient efficacy. Per the pre-specified adaptive design decision rule, only the 2.5-mg group was discontinued and the five highest doses (5, 10, 20, 50, 100 mg) were continued into the second stage. After the second interim efficacy analysis, a 200 mg dose was added due to insufficient efficacy at the top three (20, 50, 100 mg) doses. A positive dose-response trend was demonstrated when data were combined across all MK-3207 doses for two-hour pain freedom ( p < .001). The pairwise difference versus placebo for two-hour pain freedom was significant for 200 mg ( p < .001) and nominally significant for 100 mg and 10 mg ( p < .05). The incidence of adverse events appeared comparable between active treatment groups and placebo, and did not appear to increase with increasing dose.

Conclusions: MK-3207 was effective and generally well tolerated in the acute treatment of migraine.