Desvenlafaxine for the prevention of relapse in major depressive disorder: results of a randomized trial.

OBJECTIVES: To compare the efficacy and safety of desvenlafaxine (administered as desvenlafaxine succinate) with placebo in reducing relapse rate in patients with major depressive disorder (MDD). METHODS: This phase 3, multicenter, randomized trial included a 12-week, open-label (OL) treatment phase (intent-to-treat population, n = 575) followed by a 6-month, double-blind (DB) relapse prevention phase. Patients who responded to the OL treatment (17-item Hamilton Rating Scale for Depression total score or= 16 at any visit, Clinical Global Impression-Improvement score >or= 6 at any visit, or discontinuation due to unsatisfactory response). RESULTS: Patients receiving desvenlafaxine (n = 189) experienced significantly longer times to relapse of MDD versus patients receiving placebo (n = 185) during the DB period (log-rank test, P < 0.0001). The percentages of patients relapsing were 42% (78/185) and 24% (45/189) for placebo and desvenlafaxine, respectively (P < 0.001). The most common primary reason cited for discontinuation in the OL period was adverse events (19%), which consisted of nausea, dizziness, and insomnia. A total of 159 patients (42%) discontinued treatment during the DB period, including 101 placebo- (55%) and 58 desvenlafaxine-treated patients (31%). The most frequent adverse event reported as reason for treatment discontinuation in the DB period was depression, reported by 14 placebo- (8%) and 7 desvenlafaxine-treated patients (4%). CONCLUSIONS: Desvenlafaxine effectively prevented relapse of MDD during 6 months of DB treatment in patients who had responded to 12 weeks of OL desvenlafaxine therapy.

Desvenlafaxine 50 and 100 mg/d in the treatment of major depressive disorder: an 8-week, phase III, multicenter, randomized, double-blind, placebo-controlled, parallel-group trial and a post hoc pooled analysis of three studies.

BACKGROUND: Major depressive disorder (MDD) is a common, chronic illness associated with substantial disability and economic burden. Although a number of effective antidepressants are available, the need for new medications that are effective and well tolerated remains. OBJECTIVE: The aim of this study was to compare the efficacy and tolerability of fixed-dose desvenlafaxine 50 and 100 mg/d with placebo for MDD. A post hoc pooled analysis was conducted to evaluate this study in the context of all similarly designed, completed studies with the 2 doses. METHODS: This was an 8-week, Phase III, randomized, double-blind, duloxetine-referenced, placebo-controlled, parallel-group trial conducted in 21 centers across the United States. Duloxetine was included for assay sensitivity as a positive control; the study was not designed or powered to compare desvenlafaxine with duloxetine. Participants were outpatients aged > or =18 years with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition-defined MDD and a 17-item Hamilton Rating Scale for Depression (HAM-D(17)) score > or =20. Patients were randomly assigned at baseline to fixed-dose desvenlafaxine (50 or 100 mg/d), fixed-dose duloxetine (60 mg/d), or placebo. The primary outcome measure was HAM-D(17) total score at the final evaluation. Additional measures included the Clinical Global Impressions-Improvement (CGI-I) score, Montgomery Asberg Depression Rating Scale (MADRS) score, Clinical Global Impressions-Severity (CGI-S) score, and 6-item Hamilton Rating Scale for Depression, Bech version (HAM-D(6)). Tolerability assessments included discontinuation rates, adverse events (AEs), vital signs, and laboratory tests. The post hoc pooled analysis was performed using data from the current study and 2 previously published, positive studies that compared the efficacy and tolerability of desvenlafaxine 50 and 100 mg/d with placebo for MDD. The design and methodologies of the 2 studies were similar to the methodology of the current trial, other than not including a reference compound. RESULTS: Of the 925 patients who were screened, 287 did not meet entry criteria, and 638 patients enrolled in the study; the intent-to-treat (ITT) population included 615 patients who were evaluated for efficacy (mean [SD] age range, 38.8-40.7 [12.1-13.2] years; mean weight range, 83.3-87.0 [22.8-23.9] kg; female sex, 398 [64.7%]; white race, 458 [74.5%]). The primary end point did not reach significance based on the global F test for controlling multiplicity of the desvenlafaxine doses. Based on pairwise comparison, significantly greater improvements on the HAM-D(17) were observed in the desven-lafaxine 100 mg/d (-10.5; P = 0.028, unadjusted for multiple comparisons) and duloxetine 60 mg/d groups (-10.3; P = 0.047) compared with placebo (-8.7). Desvenlafaxine 100 mg/d and duloxetine 60 mg/d were associated with significantly better scores compared with placebo on the CGI-I, MADRS, CGI-S, and HAM-D(6). No significant differences were observed in any scale between the desvenlafaxine 50 mg/d and placebo groups. Discontinuation rates due to AEs were 5%, 7%, 13%, and 6% for the desvenlafaxine 50-mg/d, desvenlafaxine 100-mg/d, duloxetine 60-mg/d, and placebo groups, respectively. The ITT population from all 3 studies in the pooled analysis consisted of 1388 patients (mean [SD] age range, 38.8-45.7 [12.1-12.6] years; mean weight range, 73.1-87.0 [17.6-23.9] kg; female sex, 896 [64.6%]; white race, 1136 [81.8%]). Significantly greater improvements on the HAM-D(17) were observed for desvenlafaxine 50 mg/d (-11.5; P < 0.001) and 100 mg/d (-11.8; P < 0.001) versus placebo (-9.6). Both doses were significantly better than placebo on the CGI-I, MADRS, and HAM-D(6). CONCLUSIONS: The current study failed to meet its primary efficacy end point based on the a priori analysis plan. Desvenlafaxine was generally well tolerated. A post hoc pooled analysis of this trial and 2 previously published trials with both desvenlafaxine 50 and 100 mg/d found both doses to be effective for MDD compared with placebo. ClinicalTrials.gov Identifier: 00384033.

Efficacy, safety, and tolerability of fixed-dose desvenlafaxine 50 and 100 mg/day for major depressive disorder in a placebo-controlled trial.

The objective of this study was to assess the efficacy, safety, and tolerability of desvenlafaxine (administered as desvenlafaxine succinate) 50 and 100 mg/day for major depressive disorder (MDD). A multicenter, randomized, double-blind, placebo-controlled trial was conducted in Europe and South Africa. Outpatients with MDD received fixed-dose desvenlafaxine (50 or 100 mg/day) or placebo for 8 weeks. The primary efficacy variable was the 17-item Hamilton Rating Scale for Depression total score; secondary measures included Clinical Global Impressions-Improvement scores. The intent-to-treat population included 483 patients: desvenlafaxine 50 mg (n=164), desvenlafaxine 100 mg (n=158), and placebo (n=161). At the last-observation-carried-forward analysis (final evaluation) using analysis of covariance, adjusted mean changes from baseline on the Hamilton Rating Scale for Depression were significantly greater for both desvenlafaxine 50 mg (-13.2; P=0.002) and 100 mg (-13.7; P<0.001) versus placebo (-10.7). Significant differences on the Clinical Global Impressions-Improvement scores were observed for desvenlafaxine 50 mg (P=0.002) and 100 mg (P<0.001) versus placebo. Both doses of desvenlafaxine were generally well tolerated. The most common treatment-emergent adverse events were nausea, dizziness, insomnia, constipation, fatigue, anxiety, and decreased appetite. Fixed doses of desvenlafaxine 50 and 100 mg/day are safe, generally well tolerated, and effective at a clinically relevant level for the treatment of MDD.

A pooled analysis of two placebo-controlled trials of desvenlafaxine in major depressive disorder.

The efficacy, safety, and tolerability of desvenlafaxine (administered as desvenlafaxine succinate) were evaluated in two similarly designed, phase 3, randomized, double-blind, placebo-controlled, venlafaxine-extended-release-referenced, flexible-dose studies of outpatients with a primary diagnosis of major depressive disorder. Owing to a high placebo response, the individual studies were underpowered. Therefore, a post-hoc pooled analysis was performed (desvenlafaxine and placebo data were pooled; venlafaxine extended release data were not, owing to different flexible-dose regimens in the two studies). The primary outcome measure was the change from baseline on the 17-item Hamilton Rating Scale for Depression; the Clinical Global Impressions-Improvement item score was a secondary outcome. Analysis of the pooled data (using a mixed-effect model for repeated measures) revealed that after 8 weeks of treatment, desvenlafaxine was significantly better than placebo on 17-item Hamilton Rating Scale for Depression [-14.21 vs. -11.87 for desvenlafaxine and placebo, respectively; magnitude of effect=-2.34 (P<0.001)] and Clinical Global Impressions-Improvement item scores [1.95 vs. 2.32 for desvenlafaxine and placebo, respectively; magnitude of effect=-0.37 (P<0.001)]. Adverse events were comparable to those found with other drugs sharing a similar mechanism of action. These data support the efficacy, safety, and tolerability of desvenlafaxine in the treatment of major depressive disorder.

Bipolar disorder: how far are we from a rigorous definition and effective management?

Bipolar disorder is a pathological disturbance of mood, characterized by waxing and waning manic, depressive and, sometimes distinctly mixed states. A diagnosis of bipolar disorder can only be made with certainty when the manic syndrome declares itself. Most individuals who are diagnosed with this disorder will experience both poles of the illness recurrently, but depressive episodes are the commonest cause of morbidity and, indeed, of death by suicide. Twin, adoption and epidemiological studies suggest a strongly genetic aetiology. It is a genetically and phenotypically complex disorder. Thus, the genes contributing are likely to be numerous and of small effect. Individuals with bipolar disorder also display deficits on a range of neuropsychological tasks in both the acute and euthymic phases of illness and correlations between number of affective episodes experienced and task performance are commonly reported. Current self-report and observer-rated scales are optimized for unipolar depression and hence limited in their ability to accurately assess bipolar depression. The development of a specific depression rating scale will improve the assessment of bipolar depression in both research and clinical settings. It will improve the development of better treatments and interventions. Guidelines support the use of antidepressants for bipolar depression. With regard to the adverse effects of antidepressants for bipolar depression, double-blind, placebo-controlled data suggest that antidepressant monotherapy or the addition of a tricyclic antidepressant may worsen the course of bipolar disorder. Importantly, adjunctive psychotherapies add significantly (both statistically and clinically) to the efficacy of pharmacological treatment regimens. The successful management of bipolar disorder clearly demands improved recognition of bipolar disorder and effective long-term treatment for bipolar depression as well as mania.