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Suvorexant is an orexin receptor antagonist that is approved in the US, Japan and Australia for the treatment of insomnia. Using outcomes from the Insomnia Severity Index (ISI) in the core registration studies, we explored suvorexant effects on sleep problems and their impact on daytime function.Data were pooled from two similar Phase 3, randomized, double-blind, placebo-controlled, parallel-group, three-month trials in elderly (≥65 years) and non-elderly (18-64 years old) insomnia patients. Age-adjusted (non-elderly/elderly) dose-regimes of 40/30 mg and 20/15 mg were evaluated. The ISI, a 7-item self-rated questionnaire with each item rated on 0-4 scale (higher score corresponds to increasing severity), was administered to patients as an exploratory assessment in both studies at baseline and one and three months after randomization.The analysis included 1824 patients. Suvorexant improved change-from-baseline ISI total scores to a greater extent than placebo (Month three: 20/15 mg = -6.2, 40/30 mg = -6.7, placebo = -4.9, p-values for both active arms vs. placebo0.001) and resulted in a greater proportion of responders than placebo using a variety of definitions (eg, ≥6-point improvement from baseline at Month three: 20/15 mg = 55.5%, 40/30 mg = 54.9%, placebo = 42.2%, p-values for both active arms vs. placebo0.001). Additionally, the "impact of insomnia" component, which assesses the impact of insomnia on daytime function/quality-of-life, was improved to a greater extent by suvorexant than placebo.Suvorexant 20/15 mg and 40/30 mg improved sleep to a greater extent than placebo as assessed by the ISI in patients with insomnia. Improvement in sleep onset/maintenance as well as a reduction of the impact of sleep problems on daytime function contributed to the overall improvement observed in ISI total score. CLINICALTRIALS.NCT01097616, NCT01097629.

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).

Author(s): Connor, Kathryn M; Ceesay, Paulette; Hutzelmann, Jill; Snavely, Duane; Krystal, Andrew D; Trivedi, Madhukar H; Thase, Michael; Lines, Christopher; Herring, W Joseph; Michelson, David | Abstract: BackgroundWe evaluated the orexin receptor antagonist filorexant (MK-6096) for treatment augmentation in patients with major depressive disorder.MethodsWe 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.ResultsDue 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.ConclusionsThe 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).

Sex-related differences in the clinical profiles of some insomnia medications have been previously reported. 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. 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. 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). Suvorexant was generally effective and well-tolerated in both women and men with insomnia. ClinicalTrials.gov trial registration numbers: NCT01097616, NCT01097629, NCT01021813.

Test-then-pool is a simple statistical method that borrows historical information to improve efficiency of the drug development process. The original test-then-pool method examines the difference between the historical and current information and then pools the information if there is no significant difference. One drawback of this method is that a nonsignificant difference may not always imply consistency between the historical and current information. As a result, the original test-then-pool method is more likely to incorrectly borrow information from the historical control when the current trial has a small sample size. Statistically, it is more natural to use an equivalence test for examining the consistency. This manuscript develops an equivalence-based test-then-pool method for a continuous endpoint, explains the relationship between the two test-then-pool methods, explores the choice of an equivalence margin through the overlap probability, and proposes an adjustment to the nominal testing level for controlling type I error under the true consistency scenario. Furthermore, the analytical forms of the type I error and power for the two test-then-pool methods are derived, and practical considerations for using them are presented.

Study objectivesSuvorexant 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.MethodsPrespecified 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.ResultsSuvorexant 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.ConclusionsSuvorexant 20/15 mg improved sleep onset and maintenance over 3 months of nightly treatment and was generally safe and well tolerated.Clinical trial registrationClinicalTrials.gov trial registration numbers: NCT01097616, NCT01097629.

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. Copyright © 2014 John Wiley & Sons, Ltd.

Summary Background Suvorexant (MK-4305) is an orexin receptor antagonist shown to be efficacious for insomnia over 3 months. We aimed to assess its clinical profile during and after 1 year of treatment. Methods We did a randomised, placebo-controlled, parallel-group trial at 106 investigational centres in the Americas, Australia, Europe, and South Africa from December, 2009, to August, 2011. Patients aged 18 years or older with primary insomnia by DSM-IV-TR criteria were assigned using a computer-generated randomised allocation schedule to receive nightly suvorexant (40 mg for patients younger than 65 years, 30 mg for patients aged 65 years or older) or placebo at a 2:1 ratio for 1 year with a subsequent 2-month randomised discontinuation phase in which patients on suvorexant either continued suvorexant or were abruptly switched to placebo while patients on placebo remained on placebo. Treatment assignment was masked from patients and investigators. The primary objective was to assess the safety and tolerability of suvorexant for up to 1 year. Secondary objectives were to assess the efficacy of suvorexant for improving patient-reported subjective total sleep time (sTST) and time to sleep onset (sTSO) over the first month of treatment. Efficacy endpoints over the first month were assessed with a mixed model with terms for baseline value of the response variable, age, sex, region, treatment, time, and treatment by time interaction. This trial is registered with ClinicalTrials.gov, number NCT01021813. Findings 322 (62%) of 522 patients randomly assigned to receive suvorexant and 162 (63%) of 259 assigned to receive placebo completed the 1-year phase. Over 1 year, 362 (69%) of 521 patients treated with suvorexant experienced any adverse events compared with 164 (64%) of 258 treated with placebo. Serious adverse events were recorded in 27 patients (5%) who received suvorexant and 17 (7%) who received placebo. The most common adverse event, somnolence, was reported for 69 patients (13%) who received suvorexant and seven (3%) who received placebo. At month 1, suvorexant (517 patients in the efficacy population) showed greater efficacy than placebo (254 in the efficacy population) in improving sTST (38·7 min vs 16·0 min; difference 22·7, 95% CI 16·4 to 29·0; p vs −8·4 min, difference −9·5, −14·6 to −4·5; p=0·0002). Interpretation Our findings show that suvorexant was generally safe and well tolerated over 1 year of nightly treatment in patients with insomnia, with efficacy noted for subjective measures of sleep onset and maintenance. Funding Merck & Co Inc.

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

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 4weeks of MK-8998 12/16mg daily (N=86), olanzapine 10/15mg 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. Copyright © 2013 John Wiley & Sons, Ltd. key words—MK-8998; olanzapine; schizophrenia; randomized trial; T-type calcium channel antagonist

To assess the utility of orexin receptor antagonism as a novel approach to treating insomnia.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.Suvorexant showed significant (p values0.01) 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.The data suggest that orexin receptor antagonism offers a novel approach to treating insomnia.This study provides Class I evidence that suvorexant improves sleep efficiency over 4 weeks in nonelderly adult patients with primary insomnia.

BACKGROUND It has been suggested that the histamine subtype 3 receptor inverse agonists such as MK-0249 might be effective in treating attention-deficit/hyperactivity disorder (ADHD). We evaluated the effects of MK-0249 in adults with ADHD. METHOD A randomized, double-blind, placebo-controlled, incomplete block, 2-period crossover study of MK-0249 5-10 mg/d and osmotic-release oral system (OROS) methylphenidate 54-72 mg/d (active comparator) was performed in 72 men and women aged ≥ 18 to ≤ 55 years who met DSM-IV criteria for ADHD of either inattentive or combined subtype and who had a chronic course of behavior disorder. The study was conducted from August 2007 through April 2008 at 6 US sites. Primary efficacy was assessed by the mean change from baseline in the Adult ADHD Investigator Symptom Rating Scale (AISRS) total score after 4 weeks of treatment. RESULTS Change from baseline in AISRS at week 4 for MK-0249 was not different from placebo (P = .341), whereas a significant benefit was seen for OROS methylphenidate versus placebo (P < .001). Analysis of secondary end points, including the Conners Adult ADHD Rating Scales, showed results consistent with the AISRS. A similar percentage of patients reported adverse events for MK-0249 compared with placebo (73% versus 69%, respectively). However, a greater percentage of patients reported insomnia as an adverse event with MK-0249 treatment compared with placebo (32% versus 11%, respectively). CONCLUSIONS MK-0249 10 mg/d is not effective for the treatment of adult ADHD. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT00475735.

Objective: Preclinical models, receptor localization, and genetic linkage data support the role of D4 receptors in the etiology of ADHD. This proof-of-concept study was designed to evaluate MK-0929, a selective D4 receptor antagonist as treatment for adult ADHD. Method: A randomized, double-blind, placebo-controlled, crossover study was conducted in adults with primary ADHD. The primary end point was changed from baseline in total score on the Adult ADHD Investigator Symptom Rating Scale following a 4-week treatment regimen. Additional measures included Clinical Global Impression–Severity Scale, Hospital Anxiety and Depression Scale, and Brown Attention Deficit Disorder Scale and D4 genotype analysis. Results: No statistically significant treatment differences were found between MK-0929 and placebo in any of the primary or secondary assessments. Conclusion: Results from this study suggest that blockade of the D4 receptor alone is not efficacious in the treatment of adult ADHD.

Proof-of-concept in clinical trials has traditionally focused on the identification of a maximum tolerated dose with the assumption that the higher doses provide better efficacy. However, adverse events associated with a maximum tolerated dose may have a negative effect on efficacy. We present an efficient adaptive dose-finding strategy that concentrates patient assignments at and around the dose which has the best efficacy/tolerability profile based on a utility function. The strategy is applied within the setting of a crossover design. While the strategy may also be applied to parallel studies, a crossover design provides more power for a given sample size for comparisons between the optimal dose versus placebo and/or active control when it is reasonable to assume no carryover effects.

The efficacy and safety of a selective NK(1) antagonist, L-759274, was investigated in outpatients with diagnosis of major depressive disorder with melancholic features, following evidence obtained with the novel compound aprepitant that Substance P (NK(1)) antagonists may provide a unique mechanism of antidepressant activity. A randomized, double-blind placebo-controlled study was carried out. Patients, male or female, aged 18-60, scoring >/=25 points on total of first 17 items of 21-item Hamilton Depression Scale (HAMD), and scoring >/=4 (moderately ill) on Clinical Global Impressions-Severity Scale were randomized to oral L-759274 40 mg daily (n=66) or placebo (n=62) for 6 weeks. For patients receiving L-759274, improvement (mean decrease from baseline) in HAMD-17 total score was 10.7 points, compared with a mean 7.8 point improvement in patients receiving placebo (p

Suvorexant is an orexin receptor antagonist for treatment of insomnia. We report results from two pivotal phase 3 trials.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.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, with5% 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.Suvorexant improved sleep onset and maintenance over 3 months of nightly treatment and was generally safe and well tolerated.

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

This 12-week, open-label, multicenter study assessed the efficacy and safety of losartan/hydrochlorothiazide (HCTZ), alone or in combination with other antihypertensive agents, in the treatment of patients with severe systemic hypertension. Treatment began with once-daily losartan/HCTZ 50/12.5 mg. The dose was increased to 100/25 mg, if required, to achieve blood pressure (BP) control (sitting diastolic BP

The RENAAL Study is a double-blind, placebo-controlled trial to evaluate the renal protective effects of losartan in Type 2 diabetic patients with nephropathy. The study has enrolled 1513 patients and is expected to continue for 3.5 years after the last patient has been entered. Eligible patients must have a urinary albumin:creatinine ratio of at least 300 mg/g and serum creatinine between 1.3 to 3.0 mg/dL. Eligible hypertensive or normotensive patients are randomised to receive either losartan or placebo, in addition to their existing antihypertensive therapy. Medications that block angiotensin production or action, are excluded. The primary endpoint is a composite of the time to first event of doubling of serum creatinine, end-stage renal disease, or death; secondary endpoints include cardiovascular events, progression of renal disease, and changes in proteinuria; tertiary endpoints include quality of life, healthcare resource utilisation, and amputations. Patients include Caucasians (48.6%), Blacks (15.2%), Asians (16.7%), and Hispanics (18.2%). Baseline urinary albumin:creatinine ratio and serum creatinine levels average 1867 mg/g and 1.9 mg/dL, respectively. Mean systolic and diastolic blood pressures are 153 and 82 mmHg, respectively. RENAAL will document whether blockade of the AII receptor with losartan produces clinical benefits in patients with Type 2 diabetes and nephropathy.

The localization of substance P in brain regions that coordinate stress responses and receive convergent monoaminergic innervation suggested that substance P antagonists might have psychotherapeutic properties. Like clinically used antidepressant and anxiolytic drugs, substance P antagonists suppressed isolation-induced vocalizations in guinea pigs. In a placebo-controlled trial in patients with moderate to severe major depression, robust antidepressant effects of the substance P antagonist MK-869 were consistently observed. In preclinical studies, substance P antagonists did not interact with monoamine systems in the manner seen with established antidepressant drugs. These findings suggest that substance P may play an important role in psychiatric disorders.

Summary Background To determine whether specific angiotensin II receptor blockade with losartan offers safety and efficacy advantages in the treatment of heart failure over angiotensin-converting-enzyme (ACE) inhibition with captopril, the ELITE study compared losartan with captopril in older heart-failure patients. Methods We randomly assigned 722 ACE inhibitor naive patients (aged 65 years or more) with New York Heart Association (NYHA) class II-IV heart failure and ejection fractions of 40% or less to double-blind losartan (n=352) titrated to 50 mg once daily or captopril (n=370) titrated to 50 mg three times daily, for 48 weeks. The primary endpoint was the tolerability measure of a persisting increase in serum creatinine of 26·5 μmol/L or more (≥0·3 mg/dL) on therapy; the secondary endpoint was the composite of death and/or hospital admission for heart failure; and other efficacy measures were total mortality, admission for heart failure, NYHA class, and admission for myocardial infarction or unstable angina. Findings The frequency of persisting increases in serum creatinine was the same in both groups (10·5%). Fewer losartan patients discontinued therapy for adverse experiences (12·2% vs 20·8% for captopril, p=0·002). No losartan-treated patients discontinued due to cough compared with 14 in the captopril group. Death and/or hospital admission for heart failure was recorded in 9·4% of the losartan and 13·2% of the captopril patients (risk reduction 32% [95% CI -4% to +55%], p=0·075). This risk reduction was primarily due to a decrease in all-cause mortality (4·8% vs 8·7%; risk reduction 46% [95% CI 5–69%], p=0·035). Admissions with heart failure were the same in both groups (5·7%), as was improvement in NYHA functional class from baseline. Admission to hospital for any reason was less frequent with losartan than with captopril treatment (22·2% vs 29·7%). Interpretation In this study of elderly heart-failure patients, treatment with losartan was associated with an unexpected lower mortality than that found with captopril. Although there was no difference in renal dysfunction, losartan was generally better tolerated than captopril and fewer patients discontinued losartan therapy. A further trial, evaluating the effects of losartan and captopril on mortality and morbidity in a larger number of patients with heart failure, is in progress.

In clinical trials sponsored by Merck the unblinded statistician is typically an employee of the company. From a pharmaceutical industry perspective, advantages of this approach include ensuring that the unblinded statistician is knowledgeable regarding the experimental treatments, therapeutic area and study objectives; that the quality of the analysis conforms to rigorous standards; and that the allocation schedule, database and interim results are kept confidential. These advantages are felt to outweigh any potential disadvantages.

Background: Filorexant (MK-6096) is an orexin receptor antagonist; here, we evaluate the efficacy of filorexant in the treatment of insomnia in adults. Methods: A double-blind, placebo-controlled, randomized, two 4-week–period, adaptive crossover polysomnography study was conducted at 51 sites worldwide. Patients (18 to

Objectives We aimed to evaluate the efficacy of the selective H3 receptor inverse agonist MK-0249 to treat excessive daytime sleepiness (EDS). Methods In this three-period, double-blind, crossover study, 125 patients (100 men, 25 women; mean age, 48.6years) with obstructive sleep apnea receiving nasal continuous positive airway pressure therapy who had refractory EDS were randomized to 2weeks each of daily MK-0249 (5, 8, 10, or 12mg, adaptively assigned), modafinil 200mg, and placebo. At baseline and after each treatment period, six maintenance of wakefulness tests (MWT) and Psychomotor Vigilance Tasks (PVT) were conducted at 2-h intervals, beginning 1h postdose (∼09:00). The Epworth sleepiness scale (ESS), Clinical Global Impression of Severity (CGIS) and Digit Symbol Substitution Test (DSST) also were assessed. The primary end point was MWT sleep latency averaged over the first four time points (MWT-early). Results MWT-early mean change from baseline sleep latency at week 2 was 1.2min for placebo, 2.1min for MK-0249 (top two doses pooled; P >.05 vs placebo), and 5.9min for modafinil ( P ⩽.001 vs placebo). MK-0249 showed improvements vs placebo on secondary and exploratory end points of ESS, CGIS, PVT, and DSST. Insomnia adverse events (AEs) were greater for MK-0249 (combined doses, 17.5%) than for placebo (0.9%) or modafinil (1.8%). Conclusion MK-0249 did not significantly affect MWT sleep latency. However, the pattern of improvement on subjective ratings and psychomotor performance end points suggested that MK-0249 was associated with changes in aspects of cognition and performance not captured by the MWT.

The objective of our course is to provide a general understanding of statistical reasoning, an appreciation of the statistician's role in drug development, and to facilitate effective communication between statisticians and clinical researchers. Brief lectures are followed immediately by interactive workshops which reinforce statistical concepts. Major subject areas include study design, data handling, data analysis, and interpretation of results. Specific topics include bias, sample size, data collection, descriptive statistics, and basic statistical methods. One continuing workshop requires students to create a protocol and then to analyze, interpret, and present data “collected” by course staff. Other workshops exhibit concepts of random sampling and making decisions with uncertainty. Student learning and course acceptability are greatly enhanced by discussions generated by the workshops, breaking the class into small study groups during the workshops, and the personalized attention that students recei...

To evaluate the efficacy and tolerability of gaboxadol in the treatment of adult and elderly patients with primary insomnia.Randomized, double-blind, placebo-controlled, multicenter, 30-night, polysomnography studies.Sleep laboratory.Primary insomnia, 18-64 y (adult study), oror =65 y (elderly study).Adult study: gaboxadol 15 mg (GBX15; N = 148), 10 mg (GBX10; N = 154), or placebo (N = 156); elderly study: GBX10 (N = 157), gaboxadol 5 mg (GBX5; N = 153), or placebo (N=176).Primary endpoints were wake after sleep onset (WASO) and latency to persistent sleep (LPS). Slow wave sleep (SWS) was a secondary endpoint. Analyses were based on the change from baseline for the average of nights 1/2, and nights 29/30, and compared gaboxadol versus placebo. Exploratory endpoints included patient's subjective assessment of total sleep time (sTST), WASO (sWASO), time to sleep onset (sTSO), and number of awakenings (sNAW); these analyses were based on weekly means. 1) Adult study. GBX15 significantly (Por = 0.05) improved WASO through nights 29/30 but had no significant effects on LPS. No significant differences were seen for GBX10 versus placebo on WASO or LPS. GBX15 and GBX10 enhanced SWS. GBX15 significantly improved sTST, sWASO, sTSO, and sNAW at weeks 1 and 4. 2) Elderly study. GBX10 significantly improved WASO through nights 29/30; a significant improvement was also seen for GBX5 at nights 1/2 but this was not maintained through nights 29/30. GBX10 significantly improved LPS at nights 1/2 but the improvement was not maintained through nights 29/30; no significant differences were seen for GBX5 versus placebo on LPS. GBX10 and GBX5 enhanced SWS. GBX10 significantly improved sTST at week 1, and sTST, sWASO, and sNAW at week 4. Gaboxadol was generally well tolerated in both studies.The maximum studied doses of gaboxadol (GBX15 in adult patients and GBX10 in elderly patients) were effective at enhancing objective polysomnography measures of sleep maintenance and SWS, and also some subjective sleep measures, over 30 nights but had little or no effects on sleep onset. The clinical relevance of the enhancement of SWS by gaboxadol is unclear.

GABOXADOL IS A NOVEL HYPNOTIC WITH A DISTINCT MECHANISM OF ACTION COMPARED WITH CURRENT HYPNOTICS.1,2 TRADITIONAL BENZODIAZEPINE (e.g., triazolam) and non-benzodiazepine (e.g., zolpidem) hypnotics, collectively referred to as benzodiazepine receptor agonists (BzRAs), share a similar mode of action as allosteric modulators of γ-aminobutyric acid type A (GABA-A) receptors. By contrast, gaboxadol is an agonist that acts directly on the GABA binding site of the GABA-A receptor and has no affinity for the benzodiazepine binding site. It has highest functional activity for δ-containing GABA-A receptors where it behaves as a super-agonist (i.e., more efficacious than GABA in a functional assay). δ-Containing GABA-A receptors are insensitive to BzRAs, probably exist mainly extrasynaptically, and are localized predominantly in the thalamus, dentate gyrus, cerebellum, and cortex. These characteristics have led to gaboxadol being classified as a selective extrasynaptic GABA-A agonist (SEGA).3 The functional consequences of these anatomical and pharmacological differences are yet to be understood. Both BzRAs and gaboxadol appear to have sleep maintenance properties and beneficial effects on sleep onset, although less consistently with regard to sleep onset for gaboxadol. Two previous exploratory PSG studies demonstrated that short term treatment with gaboxadol 10, 15, and 20 mg increased sleep continuity over an initial 2 nights of treatment in patients with primary insomnia.4,5 Effects on measures of sleep onset were only observed in one study with gaboxadol 15 mg.4 Effects on sleep onset, as well as maintenance, have also been observed for gaboxadol in larger studies using a model of transient insomnia.6,7 From a sleep architecture perspective, clear differences are observed between BzRAs and gaboxadol. Numerous studies have shown that classical benzodiazepines promote stage 2 NREM sleep and reduce both slow wave sleep (SWS) and REM sleep, while non-benzodiazepines may increase stage 2 sleep but have no effect on other visually scored sleep stages.8–13 Gaboxadol has shown consistent increases in SWS with no significant effect on stage 2 or REM sleep in healthy adult/elderly subjects and early phase studies in patients with primary insomnia.4–6,14–17 Clear differences in NREM EEG spectral profiles are also observed between zolpidem and gaboxadol, with the latter selectively enhancing lower frequency slow wave activity (SWA), underlining a neurochemical difference in the mechanism of action between zolpidem and gaboxadol.6 Other putative sleep agents, including the 5-HT2A/2C receptor antagonists ritanserin and seganserin and the GABA reuptake inhibitor tiagabine, as well as α2δ calcium channel modulators, also increase SWS/SWA.18–21 In terms of the functional significance of sleep there has been much interest in SWS and the development of SWS-enhancing compounds for treating insomnia. There are marked age-related changes in sleep maintenance and continuity measures, but perhaps the most striking observation is that SWS is reduced with age.22–24 SWS is a marker of homeostatic sleep drive, and it is an intriguing question whether increased sleep problems seen with age are in fact the result of changes in SWS, and whether enhancement of SWS might result in more restorative, less fragmented sleep in the elderly. The objectives of the present studies were to confirm the efficacy and SWS-enhancing properties of gaboxadol in 2 large phase 3 PSG studies, one in adult and one in elderly adult patients with primary insomnia, and to determine whether the short term efficacy (1–3 nights) on objective measures of sleep seen to date could be maintained over 30 nights. Based on previous findings suggesting greater drug exposure in elderly patients (Cmax and AUC0-inf of gaboxadol 20 mg increased by approximately 40%, t½ increased from 1.5 to 2 h),25 the maximum gaboxadol dose investigated was 10 mg in the elderly patients versus 15 mg in adult patients. To our knowledge, the elderly study constitutes the largest PSG dataset yet available in this population and is the first to evaluate the PSG effects of a SWS-enhancer in elderly patients over an extended period. Since SWS declines with age, there is interest in the potential differential effects of a SWS-enhancer in the elderly compared to adult insomniac patients. The adult study is therefore presented here in the same paper to allow an illustrative comparison of elderly and adult primary insomnia patients before and after treatment with gaboxadol in large 4-week treatment studies with identical designs and specifically identical PSG entry criteria.

Objective A key assumption underlying the principle that power increases with sample size is that the standardized effect size is fixed over time. In therapeutic areas where it may be difficult to continually recruit from a homogeneous population, this assumption may not be valid; patients randomized toward the end of enrollment may derive from a more heterogeneous population and negatively impact the power of a study. Post hoc analyses were performed on clinical data from four phase III depression trials with paroxetine to evaluate this possibility. Methods Each study used a randomized, double-blind, placebo-controlled design and enrolled approximately 150 patients per treatment arm. Plots of observed p -values for the treatment difference between paroxetine and placebo (on the HAM-D 17 change from baseline score at week 8) by cumulative enrollment were made for each study. Results As previously reported, three of the four studies showed an overall significant treatment effect and one did not. In each study, a significant treatment effect was observed before approximately 100 patients had been enrolled per treatment arm. Continuing to enroll additional patients did not maintain the achieved level of significance in most instances, and in one case appeared to alter a potentially positive study into a failed study. Plots of p -values versus cumulative enrollment by patient quarters using combined data from all four studies suggested that late-enrolling patients were more likely to be placebo responders than early-enrolling patients. Hypothesized explanations for this finding include a depleted pool of depressed patients and the rush for patient recruitment at the end of a study in order to meet completion timelines. However, no corroborative evidence could be found to support either possibility. Conclusions This analysis demonstrates that bigger is not necessarily better for depression trials.

Background An early clinical trial suggested that the substance P (neurokinin 1 receptor) antagonist, aprepitant, might provide a unique mechanism of antidepressant activity. Phase III trials were conducted to confirm these findings. Methods Five 8-week, randomized, double-blind, parallel-groups, placebo-controlled, multicenter trials in outpatients with Major Depressive Disorder were performed. Aprepitant 160 mg and placebo were included in all trials. Aprepitant 80 mg and paroxetine 20 mg (active comparator) were included in three trials. Approximately 150 patients were enrolled per treatment group in each trial. The primary end point was the mean change-from-baseline of the first 17 items of the Hamilton Rating Scale for Depression (HAM-D 17 ) score at 8 weeks. A positron emission tomography (PET) study was also performed in normal subjects to determine the relationship between neurokinin 1 receptor occupancy and aprepitant plasma concentrations in dosing regimens relevant to the trials. Results No statistically significant differences from placebo on the HAM-D 17 were observed at week 8 for either dose of aprepitant in any of the trials, whereas paroxetine 20 mg was significantly ( p ≤ .05) more effective than placebo at week 8 in each of the three trials in which it was included. Results from the PET study indicated that the aprepitant dosing regimens provided continuously high levels of neurokinin 1 receptor blockade over 8 weeks. Conclusions Because the methodology employed confirmed the antidepressant efficacy of paroxetine, the absence of an effect for aprepitant indicates that it was not an effective treatment for depression. The concept of neurokinin 1 receptor antagonism as an antidepressant mechanism was not supported.

The pharmacokinetics and pharmacodynamics of 7 days of treatment with losartan 50 mg/hydrochlorothiazide 12.5 mg were evaluated in 14 patients with normal renal function and in 12 patients with mild to moderate renal impairment. The efficacy of losartan 50 mg/hydrochlorothiazide 12.5 mg titrated to losartan 100 mg/hydrochlorothiazide 25 mg was examined in 32 hypertensive patients with mild to moderate renal impairment who were treated for 12 weeks. Safety was assessed in both studies by the incidence of adverse experiences. After 7 days of treatment, the AUC for losartan, E-3174, and hydrochlorothiazide was slightly higher in patients with mild to moderate renal impairment, but the reduction in blood pressure (BP) after 7 days was not different between the two groups. The final (week 12) mean reductions in trough sitting diastolic and systolic BP were 15.0 +/- 7.1 mmHg (p < 0.01) and 20.8 +/- 16.7 mmHg (p < 0.01), respectively. There were no observed increases in drug-related adverse experiences in either study. Overall, the combination of losartan/hydrochlorothiazide was effective in lowering blood pressure and was well tolerated in patients with mild to moderate renal impairment.

The Losartan Heart Failure ELITE Study recently found that in patients with symptomatic heart failure and a left ventricular ejection fraction of ≤0.40, losartan compared to captopril improved survival with better tolerability. The objective of this study was to perform an economic evaluation of losartan versus captopril based on the results of the Losartan Heart Failure ELITE Study. The Losartan Heart Failure ELITE Study was a multinational, double-blind, randomized 48-week study comparing the safety and efficacy of losartan to captopril in angiotensin-converting enzyme-inhibitor-naive patients ≥65 years with symptomatic heart failure. Data on health care resource utilization were collected as part of the trial. We conducted a cost-effectiveness analysis to estimate the lifetime benefits of treatment and the associated costs. We observed no differences between treatments in the number of hospitalizations, hospital days, and emergency room visits per patient over the trial period. We estimated the total cost of losartan to be USD 54 (95% CI: USD –1,717, USD 1,755) less per patient than captopril over this time frame. We also estimated that over the projected remaining lifetime of the study population, losartan compared to captopril would increase survival by 0.20 years (undiscounted) at an average cost of USD 769 (discounted) more per patient. This cost increase translated into a cost-effectiveness ratio of USD 4,047 per year of life gained for losartan relative to captopril. In patients with symptomatic heart failure, losartan compared to captopril increased survival with better tolerability at a cost well within the range accepted as cost-effective.