A double-blind comparison of the efficacy and safety of milnacipran and fluoxetine in depressed inpatients

Comparison of Hamilton Depression Rating Scale and Montgomery-Åsberg Depression Rating Scale: Baked Straight From a Randomized Study

BACKGROUND AND OBJECTIVES

The symptoms of major depressive disorder (MDD) are nowadays being assessed with the Hamilton and Montgomery-Åsberg Depression Rating Scales. However, there are few studies on the comparison of these two scales. Our study aimed to determine the correlation between the Hamilton Depression Rating Scale (HDRS) and Montgomery-Åsberg Depression Rating Scale (MADRS) scores at baseline through 12 weeks.

METHODS

An ongoing randomized, open-label, three-arm study's interim analysis is portrayed here. The participants were assessed with HDRS and MADRS at baseline, four, eight, and 12 weeks after receiving oral tablets of either vilazodone (20-40 mg/d), escitalopram (10-20 mg/d), or vortioxetine (5-20 mg/d). This study is prospectively registered with the Clinical Trial Registry, India (CTRI/2022/07/043808).

RESULTS

Of 71 recruited individuals, 49 (69%) completed the 12-week visit. At baseline, the three groups' median HDRS scores were 30.0, 29.5, and 29.0 (p=0.76), and at 12 weeks, they reduced to 19.5, 19.5, and 18.0 (p=0.18). At baseline, the group-wise median MADRS scores were 36, 36, and 36 (p=0.79); at 12 weeks, they were 24, 24, and 23 (p=0.03). The Pearson correlation revealed that the association between the changes in scores from baseline was strongest for escitalopram (r=0.70, p=0.002) followed by vortioxetine (r=0.59, p=0.01) and vilazodone (r=0.59, p=0.02). The Bland-Altman analysis showed that the mean difference between the scores was 5.11 (95% CI: 3.08-7.14).

CONCLUSION

According to this interim study, HDRS and MADRS scores declined after 12 weeks of therapy. Both scores had strong positive correlation, and the difference between the scores reduced with time.

Open-label milnacipran for patients with persistent knee pain 1 year or longer after total knee arthroplasty: a pilot study

OBJECTIVE

The current study investigates whether milnacipran is effective in reducing pain and improving function in patients with persistent pain ≥ 1 year after total knee arthroplasty.

METHOD

This was a 12-week open-label study of flexibly dosed milnacipran in patients (N = 5) experiencing chronic persistent knee pain ≥ 1 year following total knee arthroplasty in the absence of new injury, infection, or implant failure. Subjects were identified from October 2010 to August 2011 through the Duke University Medical Center orthopedic clinic (Durham, North Carolina), typically during 1-year postoperative follow-up visits, and were referred by their orthopedic surgeon.

RESULTS

Milnacipran treatment was associated with reduction in pain according to the primary outcome measure of the visual analog scale (VAS) score for pain (effect size of 1.15) and secondary outcome measures of Knee Society Score (KSS) evaluation subscale score (effect size of 1.37) and Medical Outcomes Study 36-item Short-Form Health Survey (SF-36) bodily pain subscale (effect size of 1.16) at week 12. Secondary outcome measures of functional change were mixed in such that, at week 12, the SF-36 physical functioning subscale showed improvement (effect size of 1.16), but the KSS function subscale score was just below the threshold for meaningful effect size (0.98).

CONCLUSIONS

Open-label milnacipran demonstrated reduced pain and some evidence of functional improvement in this small sample of patients with chronic persistent pain 1 year or more after total knee arthroplasty such that well-powered studies are warranted.

Fluoxetine versus other types of pharmacotherapy for depression

BACKGROUND

Depression is common in primary care and is associated with marked personal, social and economic morbidity, thus creating significant demands on service providers. The antidepressant fluoxetine has been studied in many randomised controlled trials (RCTs) in comparison with other conventional and unconventional antidepressants. However, these studies have produced conflicting findings.Other systematic reviews have considered selective serotonin reuptake inhibitor (SSRIs) as a group which limits the applicability of the indings for fluoxetine alone. Therefore, this review intends to provide specific and clinically useful information regarding the effects of fluoxetine for depression compared with tricyclics (TCAs), SSRIs, serotonin-noradrenaline reuptake inhibitors (SNRIs), monoamineoxidase inhibitors (MAOIs) and newer agents, and other conventional and unconventional agents.

OBJECTIVES

To assess the effects of fluoxetine in comparison with all other antidepressive agents for depression in adult individuals with unipolar major depressive disorder.

SEARCH METHODS

We searched the Cochrane Collaboration Depression, Anxiety and Neurosis Review Group Controlled Trials Register (CCDANCTR)to 11May 2012. This register includes relevant RCTs from the Cochrane Central Register of Controlled Trials (CENTRAL) (all years),MEDLINE (1950 to date), EMBASE (1974 to date) and PsycINFO (1967 to date). No language restriction was applied. Reference lists of relevant papers and previous systematic reviews were handsearched. The pharmaceutical company marketing fluoxetine and experts in this field were contacted for supplemental data.

SELECTION CRITERIA

All RCTs comparing fluoxetine with any other AD (including non-conventional agents such as hypericum) for patients with unipolar major depressive disorder (regardless of the diagnostic criteria used) were included. For trials that had a cross-over design only results from the first randomisation period were considered.

DATA COLLECTION AND ANALYSIS

Data were independently extracted by two review authors using a standard form. Responders to treatment were calculated on an intention-to-treat basis: dropouts were always included in this analysis. When data on dropouts were carried forward and included in the efficacy evaluation, they were analysed according to the primary studies; when dropouts were excluded from any assessment in the primary studies, they were considered as treatment failures. Scores from continuous outcomes were analysed by including patients with a final assessment or with the last observation carried forward. Tolerability data were analysed by calculating the proportion of patients who failed to complete the study due to any causes and due to side effects or inefficacy. For dichotomous data, odds ratios (ORs) were calculated with 95% confidence intervals (CI) using the random-effects model. Continuous data were analysed using standardised mean differences (SMD) with 95% CI.

MAIN RESULTS

A total of 171 studies were included in the analysis (24,868 participants). The included studies were undertaken between 1984 and 2012. Studies had homogenous characteristics in terms of design, intervention and outcome measures. The assessment of quality with the risk of bias tool revealed that the great majority of them failed to report methodological details, like the method of random sequence generation, the allocation concealment and blinding. Moreover, most of the included studies were sponsored by drug companies, so the potential for overestimation of treatment effect due to sponsorship bias should be considered in interpreting the results. Fluoxetine was as effective as the TCAs when considered as a group both on a dichotomous outcome (reduction of at least 50% on the Hamilton Depression Scale) (OR 0.97, 95% CI 0.77 to 1.22, 24 RCTs, 2124 participants) and a continuous outcome (mean scores at the end of the trial or change score on depression measures) (SMD 0.03, 95% CI -0.07 to 0.14, 50 RCTs, 3393 participants). On a dichotomousoutcome, fluoxetine was less effective than dothiepin or dosulepin (OR 2.13, 95% CI 1.08 to 4.20; number needed to treat (NNT) =6, 95% CI 3 to 50, 2 RCTs, 144 participants), sertraline (OR 1.37, 95% CI 1.08 to 1.74; NNT = 13, 95% CI 7 to 58, 6 RCTs, 1188 participants), mirtazapine (OR 1.46, 95% CI 1.04 to 2.04; NNT = 12, 95% CI 6 to 134, 4 RCTs, 600 participants) and venlafaxine(OR 1.29, 95% CI 1.10 to 1.51; NNT = 11, 95% CI 8 to 16, 12 RCTs, 3387 participants). On a continuous outcome, fluoxetine was more effective than ABT-200 (SMD -1.85, 95% CI -2.25 to -1.45, 1 RCT, 141 participants) and milnacipran (SMD -0.36, 95% CI-0.63 to -0.08, 2 RCTs, 213 participants); conversely, it was less effective than venlafaxine (SMD 0.10, 95% CI 0 to 0.19, 13 RCTs,3097 participants). Fluoxetine was better tolerated than TCAs considered as a group (total dropout OR 0.79, 95% CI 0.65 to 0.96;NNT = 20, 95% CI 13 to 48, 49 RCTs, 4194 participants) and was better tolerated in comparison with individual ADs, in particular amitriptyline (total dropout OR 0.62, 95% CI 0.46 to 0.85; NNT = 13, 95% CI 8 to 39, 18 RCTs, 1089 participants), and among the newer ADs ABT-200 (total dropout OR 0.18, 95% CI 0.08 to 0.39; NNT = 3, 95% CI 2 to 5, 1 RCT, 144 participants), pramipexole(total dropout OR 0.12, 95% CI 0.03 to 0.42, NNT = 3, 95% CI 2 to 5, 1 RCT, 105 participants), and reboxetine (total dropout OR0.60, 95% CI 0.44 to 0.82, NNT = 9, 95% CI 6 to 24, 4 RCTs, 764 participants).

AUTHORS' CONCLUSIONS

The present study detected differences in terms of efficacy and tolerability between fluoxetine and certain ADs, but the clinical meaning of these differences is uncertain.Moreover, the assessment of quality with the risk of bias tool showed that the great majority of included studies failed to report details on methodological procedures. Of consequence, no definitive implications can be drawn from the studies' results. The better efficacy profile of sertraline and venlafaxine (and possibly other ADs) over fluoxetine may be clinically meaningful,as already suggested by other systematic reviews. In addition to efficacy data, treatment decisions should also be based on considerations of drug toxicity, patient acceptability and cost.

Double-blind, comparative study of milnacipran and paroxetine in Japanese patients with major depression

BACKGROUND AND METHODS

A double-blind, parallel-group, controlled study was performed to investigate if milnacipran was noninferior to paroxetine in terms of improvement in symptoms of depression in Japanese patients with major depressive disorders in a fixed-dose design. The efficacy and safety of milnacipran 200 mg/day were also assessed in comparison with those at the standard dose of 100 mg/day.

RESULTS

Changes in 17-item Hamilton depression rating scale (HAM-D) total score (mean ± standard deviation) for group M1 (milnacipran 100 mg/day), group M2 (milnacipran 200 mg/day), and group PX (paroxetine 30 or 40 mg/day) were -12.9 ± 5.8, -12.8 ± 6.1, and -13.1 ± 6.2, respectively, and the estimated differences in total score for group PX (Dunnett's 95% simultaneous confidence interval) were 0.1 (-1.1 to 1.3) for group M1 and 0.3 (-0.9 to 1.5) for group M2. The noninferiority of groups M1 and M2 to group PX was thus confirmed, because the upper confidence limit of differences between groups M1 and PX and between groups M2 and PX was less than 2.0. The estimated mean difference of change in HAM-D total score (95% confidence interval) between groups M2 and M1 was 0.2 (-0.9 to 1.2), indicating a comparable change in total score for both groups. The incidence of treatment-related adverse events was 71.7% for group M1, 68.8% for group M2, and 69.3% for group PX, indicating no significant difference between the three groups.

CONCLUSION

These results demonstrate that milnacipran 100 mg/day and 200 mg/day is not inferior to paroxetine in terms of efficacy and safety.

Classical and novel approaches to the preclinical testing of anxiolytics: A critical evaluation

Over 80% of current anxiety studies employ one of the tests that were developed earlier than, or concurrently with the elevated plus-maze, i.e. before 1985. Considering 1985 as a historical reference point, we briefly review here 115 new tests and models of anxiety, the development of which was likely prompted by the poor predictive validity of classical tests as shown here by the comparison of preclinical and clinical findings with putative novel anxiolytics. The new approaches comprise major innovations to classical tests, the pre-test application of manipulations that mimic etiological factors of anxiety disorders, and entirely new approaches including anxiety disorder-specific tests. Thus, intensive test development over the last 27 years created a large pool of novel approaches. However, these are infrequently used and as such, their impact on anxiolytic drug development remains low. We suggest here that test/model development should step over the intensive phase when several new methods are proposed each year and should start selecting and establishing the methodologies that would successfully replace or complement classical tests. We propose here a novel strategy for improving the validity of anxiety testing that includes the retrospective analysis of the predictive validity of new procedures (as opposed to classical pharmacological validation), and a call for concerted international efforts at both the conceptual and practical levels. Similar endeavors proved recently successful with other psychiatric disorders.

Milnacipran: a unique antidepressant?

Tricyclic antidepressants (TCAs) are among the most effective antidepressants available, although their poor tolerance at usual recommended doses and toxicity in overdose make them difficult to use. While selective serotonin reuptake inhibitors (SSRIs) are better tolerated than TCAs, they have their own specific problems, such as the aggravation of sexual dysfunction, interaction with coadministered drugs, and for many, a discontinuation syndrome. In addition, some of them appear to be less effective than TCAs in more severely depressed patients. Increasing evidence of the importance of norepinephrine in the etiology of depression has led to the development of a new generation of antidepressants, the serotonin and norepinephrine reuptake inhibitors (SNRIs). Milnacipran, one of the pioneer SNRIs, was designed from theoretic considerations to be more effective than SSRIs and better tolerated than TCAs, and with a simple pharmacokinetic profile. Milnacipran has the most balanced potency ratio for reuptake inhibition of the two neurotransmitters compared with other SNRIs (1:1.6 for milnacipran, 1:10 for duloxetine, and 1:30 for venlafaxine), and in some studies milnacipran has been shown to inhibit norepinephrine uptake with greater potency than serotonin (2.2:1). Clinical studies have shown that milnacipran has efficacy comparable with the TCAs and is superior to SSRIs in severe depression. In addition, milnacipran is well tolerated, with a low potential for pharmacokinetic drug-drug interactions. Milnacipran is a first-line therapy suitable for most depressed patients. It is frequently successful when other treatments fail for reasons of efficacy or tolerability.

Milnacipran: beyond a role of antidepressant

Milnacipran is a serotonin and norepinephrine reuptake inhibitor (SNRI) with negligible effects on any presynaptic or postsynaptic receptors. Milnacipran has unique pharmacokinetic and pharmacodynamic characteristics that distinguish it from the other marketed serotonin and norepinephrine reuptake inhibitors, venlafaxine, desvenlafaxine, and duloxetine such as equipotent serotonin and norepinephrine reuptake inhibition and a linear dose-concentration trend at therapeutic doses. The half-life of milnacipran is approximately 8 hours. In addition, milnacipran does not inhibit the cytochrome P 450 system, indicating minimal propensity for drug-drug interactions. The antidepressant efficacy of milnacipran has been clearly established in a number of randomized, double-blind, placebo-controlled clinical trials, and it has been widely used for treating major depressive disorder. Moreover, evidence suggests that milnacipran is effective and tolerable in the treatment of fibromyalgia and may have usefulness for fatigue and anxiety symptoms. The current paper reviews researches conducted to date that is relevant to the efficacy, tolerability, and mechanism of action of milnacipran in the treatment of depression, fibromyalgia, and other psychiatric syndromes. Future directions of research are also identified.

Milnacipran versus other antidepressive agents for depression

BACKGROUND

Although pharmacological and psychological interventions are both effective for major depression, antidepressant drugs are frequently used as first-line treatment in primary and secondary care settings. Milnacipran, a dual serotonin-norepinephrine reuptake inhibitor (SNRI), is one of the antidepressant drugs that clinicians use for routine depression care.

OBJECTIVES

To assess the evidence for the efficacy, acceptability and tolerability of milnacipran in comparison with tricyclic antidepressants (TCAs), heterocyclics, SSRIs and other newer antidepressive agents in the acute-phase treatment of major depression.

SEARCH STRATEGY

The Cochrane Collaboration Depression, Anxiety & Neurosis review group Controlled Trials Register (CCDANCTR-Studies and CCDANCTR-References) were electronically searched in August 2008. References of relevant trials and other reviews were also checked. Trial databases of the drug-approving agencies and ongoing clinical trial registers for all published and unpublished trials were hand-searched in 2007. All relevant authors were contacted for supplemental data. No language restriction was applied.

SELECTION CRITERIA

Randomised controlled trials comparing milnacipran with any other active antidepressive agents (including non-conventional agents such as herbal products like hypericum) as monotherapy in the acute phase of major depression were selected.

DATA COLLECTION AND ANALYSIS

Two reviewers independently checked eligibility, assessed methodological quality and extracted data from the eligible trials using a standardised data extraction form. The number of participants who responded to treatment or those who achieved remission were calculated on an intention-to-treat basis. Random-effects meta-analyses were conducted, combining data from the included trials.

MAIN RESULTS

A total of 16 randomised controlled trials (n=2277) were included in the meta-analysis.Despite the size of this sample, the pooled 95% confidence intervals were rather wide and there were no statistically significant differences in efficacy, acceptability and tolerability when comparing milnacipran with other antidepressive agents. However, compared with TCAs, patients taking milnacipran were associated with fewer dropouts due to adverse events (OR 0.55; 95%CI 0.35 to 0.85). There was also some weak evidence to suggest that patients taking milnacipran experienced fewer adverse events of sleepiness/ drowsiness, dry mouth or constipation compared with TCAs.

AUTHORS' CONCLUSIONS

Currently, there is inadequate evidence to conclude whether milnacipran is superior, inferior or the same as other antidepressive agents in terms of efficacy, acceptability and tolerability in the acute phase treatment of major depression. However, there is some evidence in favour of milnacipran over TCAs in terms of dropouts due to adverse events (acceptability) and the rates of experiencing adverse events (tolerability). Information about other clinically meaningful outcomes such as cost-effectiveness and social functioning, including the ability to return to work, is lacking. Further study is needed to answer whether milnacipran would be the better choice of antidepressant for acute major depression.

Comparative efficacy and acceptability of 12 new-generation antidepressants: a multiple-treatments meta-analysis

BACKGROUND

Conventional meta-analyses have shown inconsistent results for efficacy of second-generation antidepressants. We therefore did a multiple-treatments meta-analysis, which accounts for both direct and indirect comparisons, to assess the effects of 12 new-generation antidepressants on major depression.

METHODS

We systematically reviewed 117 randomised controlled trials (25 928 participants) from 1991 up to Nov 30, 2007, which compared any of the following antidepressants at therapeutic dose range for the acute treatment of unipolar major depression in adults: bupropion, citalopram, duloxetine, escitalopram, fluoxetine, fluvoxamine, milnacipran, mirtazapine, paroxetine, reboxetine, sertraline, and venlafaxine. The main outcomes were the proportion of patients who responded to or dropped out of the allocated treatment. Analysis was done on an intention-to-treat basis.

FINDINGS

Mirtazapine, escitalopram, venlafaxine, and sertraline were significantly more efficacious than duloxetine (odds ratios [OR] 1.39, 1.33, 1.30 and 1.27, respectively), fluoxetine (1.37, 1.32, 1.28, and 1.25, respectively), fluvoxamine (1.41, 1.35, 1.30, and 1.27, respectively), paroxetine (1.35, 1.30, 1.27, and 1.22, respectively), and reboxetine (2.03, 1.95, 1.89, and 1.85, respectively). Reboxetine was significantly less efficacious than all the other antidepressants tested. Escitalopram and sertraline showed the best profile of acceptability, leading to significantly fewer discontinuations than did duloxetine, fluvoxamine, paroxetine, reboxetine, and venlafaxine.

INTERPRETATION

Clinically important differences exist between commonly prescribed antidepressants for both efficacy and acceptability in favour of escitalopram and sertraline. Sertraline might be the best choice when starting treatment for moderate to severe major depression in adults because it has the most favourable balance between benefits, acceptability, and acquisition cost.

Efficacy and tolerability of milnacipran in the treatment of major depression in comparison with other antidepressants : a systematic review and meta-analysis

BACKGROUND

Milnacipran, a dual serotonin-noradrenaline reuptake inhibitor, is one of the newer antidepressants that clinicians use for the routine care of patients with major depression. We undertook a systematic review and meta-analysis of randomized controlled trials that compared the efficacy and tolerability of milnacipran with other antidepressants.

OBJECTIVE

To assess the efficacy and tolerability of milnacipran in comparison with TCAs, SSRIs and other drugs in the acute phase of treatment for major depression.

METHODS

We searched the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials registers, journals, conference proceedings, trial databases of the drug-approving agencies and ongoing clinical trial registers for all published and unpublished randomized controlled trials that compared the efficacy and adverse events of milnacipran versus any other antidepressant. The search was conducted in December 2006 and updated in May 2007. No language restrictions were applied. All relevant authors were contacted to supplement any incomplete reporting in the original papers. Randomized controlled trials comparing milnacipran with any other active antidepressants as monotherapy in the acute phase of treatment for major depression were selected. Participants were aged > or =18 years, of both sexes and with a primary diagnosis of unipolar major depression. Studies were excluded when the participants had specific psychiatric and medical co-morbidities. Two independent reviewers assessed the quality of trials for inclusion, and subsequently extracted data. Disagreements were resolved by consensus. Meta-analyses were conducted for efficacy and tolerability outcomes. Sixteen randomized controlled trials (n = 2277) were included in the meta-analyses.

RESULTS

No differences were found in achieving clinical improvement, remission or overall tolerability when comparing milnacipran with other antidepressants. However, compared with the TCAs, fewer patients taking milnacipran were early treatment withdrawals due to adverse events (number needed to harm (NNH) = 15; 95% CI 10, 48). Significantly more patients taking TCAs experienced adverse events compared with milnacipran (NNH = 4; 95% CI 3, 7).

CONCLUSIONS

The overall effectiveness and tolerability of milnacipran versus other antidepressants does not seem to differ in the acute phase of treatment for major depression. However, there is some evidence in favour of milnacipran over TCAs in terms of premature withdrawal due to adverse events and the rates of patients experiencing adverse events. Milnacipran may benefit some patient populations who experience adverse effects from other antidepressants in the acute phase of treatment for major depression.

Are antidepressant drugs that combine serotonergic and noradrenergic mechanisms of action more effective than the selective serotonin reuptake inhibitors in treating major depressive disorder? A meta-analysis of studies of newer agents

BACKGROUND

Recent studies suggest that the treatment of major depressive disorder (MDD) with newer antidepressant drugs that simultaneously enhance norepinephrine and serotonin neurotransmission might result in higher response and remission rates than the selective serotonin reuptake inhibitors (SSRIs). The goal of our work was to compare response rates among patients with MDD treated with either of these two broad categories of antidepressant drugs.

METHODS

Medline/Pubmed, EMBase, clinical trial registries, program syllabi from major psychiatric meetings held since 1995, and documents from relevant pharmaceutical companies were searched for double-blind, randomized trials comparing a newer serotonergic-noradrenergic antidepressant drug (venlafaxine, duloxetine, milnacipran, mirtazapine, mianserin, or moclobemide) with an SSRI for MDD.

RESULTS

Ninety-three trials (n = 17,036) were combined using a random-effects model. Treatment with serotonergic + noradrenergic antidepressant drugs was more likely to result in clinical response than the SSRIs (risk ratio [RR] = 1.059; response rates 63.6% versus 59.3%; p = .003). There was no evidence for heterogeneity among studies combined (p = 1.0). Excluding each individual agent did not significantly alter the pooled RR. With the exception of duloxetine (.985), RRs for response for each individual serotonergic + noradrenergic antidepressant drug were within the 95% confidence interval of the pooled RR (1.019-1.101).

CONCLUSIONS

Serotonergic-noradrenergic antidepressant drugs seem to have a modest efficacy advantage compared with SSRIs in MDD. With the Number Needed to Treat (NNT) statistic as one indicator of clinical significance, nearly 24 patients would need to be treated with dual-action antidepressant drugs instead of SSRIs in order to obtain one additional responder. This difference falls well below the mark of NNT = 10 suggested by the United Kingdom's National Institute of Clinical Excellence but nonetheless might be of public health relevance given the large number of depressed patients treated with SSRI /serotonin-norepinephrine reuptake inhibitor (SNRI) antidepressant drugs. Further research is needed to examine whether larger differences between classes of antidepressant drugs might exist in specific MDD sub-populations or for specific MDD symptoms.

Which antidepressants have demonstrated superior efficacy? A review of the evidence

A review of published evidence of superior efficacy of a particular antidepressant in major depressive disorder may assist clinicians in making considered treatment choices. To identify such candidates, an international group of experts met to assess published evidence (identified through searches in Medline and Embase databases and discussions with experts in the field) from randomized, controlled trials and meta-analyses comparing two antidepressants under conditions of fair comparison. Criteria were defined to judge the strength of evidence. Two pivotal studies in moderate-to-severe major depressive disorder that demonstrate superiority on the primary efficacy measure, or alternatively one pivotal study supported by consistent results from meta-analyses, was considered to constitute evidence for definite superiority. Three antidepressants met these criteria: clomipramine, venlafaxine, and escitalopram. Three antidepressants were found to have probable superiority: milnacipran, duloxetine, and mirtazapine. Only escitalopram was found to have definite superiority in the treatment of severe depression; probable superiority was identified for venlafaxine and possible superiority for milnacipran and clomipramine. This review of published data found evidence that only a very few antidepressants are shown to be more effective than others.

The burden of severe depression: a review of diagnostic challenges and treatment alternatives

Among the factors making recognition of severe depression problematic for clinicians are the heterogeneous nature of the condition, lack of standardized definitions, and concomitant comorbidities that confound differential diagnosis of symptoms. The spectrum of severity in depressive disorders is extraordinarily broad, and severity assessment is comprised of several metrics including symptom intensity, diagnostic subtypes, suicidality risk, and hospitalization status. The overall diagnosis is achieved through consideration of symptom types and severities together with the degree of functional impairment as assessed by the psychiatric interview. It is likely that no single fundamental neurobiological defect underlies severe depression. The chronicity and heterogeneity of this disorder lead to frequent clinic visits and a longer course of treatment; therefore, successful approaches may require an arsenal of treatments with numerous mechanisms of action. The categories of drugs used to treat severe depression are detailed herein, as are several non-pharmacologic options including a number of experimental treatments. Pharmacotherapies include tricyclic antidepressants, selective serotonin reuptake inhibitors, atypical antidepressants such as serotonin-norepinephrine reuptake inhibitors and monoamine oxidase inhibitors, and combination and augmentation therapies. Drugs within each class are not equivalent, and efficacy may vary with symptom severity. Patient adherence makes tolerability another critical consideration in antidepressant choice. The role of non-pharmacological treatments such as electroconvulsive therapy, vagus nerve stimulation, transcranial magnetic stimulation, and deep brain stimulation remain active avenues of investigation. Improved knowledge and treatment approaches for severe depression are necessary to facilitate remission, the ideal treatment goal.

A meta-analysis of clinical trials comparing milnacipran, a serotonin--norepinephrine reuptake inhibitor, with a selective serotonin reuptake inhibitor for the treatment of major depressive disorder

CONTEXT

Over the past few years, a number of studies have emerged suggesting that the treatment of major depressive disorder (MDD) with antidepressants which enhance both noradrenergic as well as serotonergic neurotransmission may result in higher response or remission rates than treatment with antidepressants which selectively enhance serotonergic neurotransmission.

OBJECTIVE

The objective of this paper was to compare response rates among patients with MDD treated with either milnacipran, an antidepressant thought to simultaneously enhance both noradrenergic and serotonergic neurotransmission, or a selective serotonin reuptake inhibitor (SSRI).

DATA SOURCES

Medline/Pubmed were searched. No year of publication or language limits were used.

STUDY SELECTION

Double-blind, randomized clinical trials comparing milnacipran with an SSRI for the treatment of MDD.

DATA EXTRACTION

Data were extracted with the use of a pre-coded form.

DATA SYNTHESIS

Analyses were performed comparing response rates between the two antidepressant agents. Data from 6 reports involving a total of 1082 outpatients with MDD were identified and combined using a random-effects model. Patients randomized to treatment with milnacipran were as likely to experience clinical response as patients randomized to treatment with an SSRI according to the MADRS (RR = 1.04, 95% CI: 0.88-1.23, p = 0.533) or the HDRS (RR = 1.06, 95% CI: 0.90-1.24, p = 0.456) for the random effects model. Simply pooling MADRS-based response rates between the two agents revealed a 58.9% response rate for milnacipran and a 58.3% response rate for the SSRIs. Similarly, HDRS-based response rates were 59.7% and 57.5%. There was also no difference in overall discontinuation rates (RR = 0.93; 95% CI: 0.76-1.14; p = 0.506), the rate of discontinuation due to adverse events (RR = 0.77; 95% CI: 0.55-1.1; p = 0.157), or the rate of discontinuation due to inefficacy (RR = 0.98; 95% CI: 0.7-1.38; p = 0.95) between the two groups.

CONCLUSIONS

These results suggest that milnacipran and the SSRIs do not differ with respect to their overall efficacy in the treatment of MDD.

Remission Rates with Milnacipran 100??Mg/Day and 150 Mg/Day in??the??Long-Term Treatment of??Major Depression

BACKGROUND

The aim of this study was to determine remission rates during treatment with two different dosages of milnacipran, and the effect of milnacipran therapy for at least 1 year on the maintenance of remission and tolerability, in outpatients with major depression.

METHODS

The study included 41 outpatients with major depression who initially received milnacipran 50 mg/day for 1-2 weeks, followed by a dosage increase to 100 mg/day for 12 weeks. Patients who achieved remission (17-item Hamilton Depression Rating Scale [HDRS] scores <or=7) after 12 weeks of milnacipran 100 mg/day treatment continued at the same dosage and were followed for at least 1 year. For patients who had decreased HDRS scores, but failed to attain remission, the dosage of milnacipran was increased to 150 mg/day, and those who achieved remission were then followed for at least 1 year.

RESULTS

Eight out of 41 patients were withdrawn from the study prematurely because of adverse events (eight events in six patients: nausea, thirst, urinary discomfort, rapid pulse, palpitations, staggering sensation or sweating) or as a result of the patient's decision (two patients). Thirteen (31.7%) of 41 patients achieved remission during treatment with milnacipran 100 mg/day. Of the remaining 20 patients, 17 underwent a dosage increase to 150 mg/day, and 13 achieved remission at a second assessment (cumulative remission rate: 63.4%). No adverse events or recurrence of symptoms were found in any of the patients who achieved remission during the subsequent follow-up period of a minimum of 1 year.

CONCLUSIONS

The results of this study showed milnacipran 150 mg/day and 100 mg/day to be effective and well tolerated in the long-term treatment of outpatients with major depression, and indicated that a dosage of 150 mg/day is an effective therapeutic option for depression when a dosage of 100 mg/day does not provide a satisfactory response.

Duloxetine: A balanced and selective norepinephrine- and serotonin-reuptake inhibitor

PURPOSE

The pharmacology, pharmacokinetics, efficacy, safety, drug interactions, dosage and administration, cost, and place in therapy of duloxetine for major depression, pain from diabetic peripheral neuropathy, and stress urinary incontinence are reviewed.

SUMMARY

Duloxetine is a balanced selective serotonin and norepinephrine-reuptake inhibitor available in the United States for the treatment of major depressive disorder (MDD) and diabetic peripheral neuropathic pain (DPNP). Duloxetine has also been used for the treatment of stress urinary incontinence (SUI). Absorption of duloxetine begins two hours after oral administration, reaching a maximum plasma concentration in six hours. Half-life and volume of distribution are 12 hours and 1640 L, respectively. The recommended dosage of duloxetine is 40-80 mg daily, depending on the indication, preferably split into two doses per day. For the treatment of major depression, duloxetine has achieved remission rates similar to that of existing selective serotonin-reuptake inhibitors (SSRIs). For SUI and pain associated with diabetic peripheral neuropathy, duloxetine has not demonstrated equivalence or superiority to existing therapies. The adverse effects of duloxetine are similar to those of traditional SSRIs. Nausea is common and has been cited as the primary reason for discontinuation of duloxetine in trials. Increases in blood pressure have been mild, but caution should be used in patients with hypertension. Patients with a creatinine clearance of <30 mL/min and patients with hepatic impairment should avoid duloxetine. Duloxetine should not be recommended as first-line therapy for SUI or DPNP. For MDD, duloxetine may be a useful alternative for patients who do not benefit from or are unable to tolerate other antidepressant therapy.

CONCLUSION

Duloxetine has been approved for the treatment of MDD and pain associated with diabetic peripheral neuropathy in adults.

Fluoxetine versus other types of pharmacotherapy for depression

BACKGROUND

Depression is common in primary care and it is associated with marked personal, social and economic morbidity, and creates significant demands on service providers in terms of workload. Treatment is predominantly pharmaceutical or psychological. Fluoxetine, the first of a group of antidepressant (AD) agents known as selective serotonin reuptake inhibitors (SSRIs), has been studied in many randomised controlled trials (RCTs) in comparison with tricyclic (TCA), heterocyclic and related ADs, and other SSRIs. These comparative studies provided contrasting findings. In addition, systematic reviews of RCTs have always considered the SSRIs as a group, and evidence applicable to this group of drugs might not be applicable to fluoxetine alone. The present systematic review assessed the efficacy and tolerability profile of fluoxetine in comparison with TCAs, SSRIs and newer agents.

OBJECTIVES

To determine the efficacy of fluoxetine, compared with other ADs, in alleviating the acute symptoms of depression, and to review its acceptability.

SEARCH STRATEGY

Relevant studies were located by searching the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register (CCDANCTR), the Cochrane Central Register of Controlled Trials (CENTRAL), Medline (1966-2004) and Embase (1974-2004). Non-English language articles were included.

SELECTION CRITERIA

Only RCTs were included. For trials which have a crossover design only results from the first randomisation period were considered.

DATA COLLECTION AND ANALYSIS

Data were independently extracted by two reviewers using a standard form. Responders to treatment were calculated on an intention-to-treat basis: drop-outs were always included in this analysis. When data on drop-outs were carried forward and included in the efficacy evaluation, they were analysed according to the primary studies; when dropouts were excluded from any assessment in the primary studies, they were considered as treatment failures. Scores from continuous outcomes were analysed including patients with a final assessment or with the last observation carried forward. Tolerability data were analysed by calculating the proportion of patients who failed to complete the study and who experienced adverse reactions out of the total number of randomised patients. The primary analyses used a fixed effects approach, and presented Peto Odds Ratio (PetoOR) and Standardised Mean Difference (SMD).

MAIN RESULTS

On a dichotomous outcome fluoxetine was less effective than dothiepin (PetoOR: 2.09, 95% CI 1.08 to 4.05), sertraline (PetoOR: 1.40, 95% CI 1.11 to 1.76), mirtazapine (PetoOR: 1.64, 95% CI 1.01 to 2.65) and venlafaxine (Peto OR: 1.40, 95% CI 1.15 to 1.70). On a continuous outcome, fluoxetine was more effective than ABT-200 (Standardised Mean Difference (SMD) random effects: - 1.85, 95% CI - 2.25 to - 1.45) and milnacipran (SMD random effects: - 0.38, 95% CI - 0.71 to - 0.06); conversely, it was less effective than venlafaxine (SMD random effect: 0.11, 95% CI 0.00 to 0.23), however these figures were of borderline statistical significance. Fluoxetine was better tolerated than TCAs considered as a group (PetoOR: 0.78, 95% CI 0.68 to 0.89), and was better tolerated in comparison with individual ADs, in particular than amitriptyline (PetoOR: 0.64, 95% CI 0.47 to 0.85) and imipramine (PetoOR: 0.79, 95% CI 0.63 to 0.99), and among newer ADs than ABT-200 (PetoOR: 0.21, 95% CI 0.10 to 0.41), pramipexole (PetoOR: 0.20, 95% CI 0.08 to 0.47) and reboxetine (PetoOR: 0.61, 95% CI 0.40 to 0.94).

AUTHORS' CONCLUSIONS

There are statistically significant differences in terms of efficacy and tolerability between fluoxetine and certain ADs, but the clinical meaning of these differences is uncertain, and no definitive implications for clinical practice can be drawn. From a clinical point of view the analysis of antidepressants' safety profile (adverse effect and suicide risk) remains of crucial importance and more reliable data about these outcomes are needed. Waiting for more robust evidence, treatment decisions should be based on considerations of clinical history, drug toxicity, patient acceptability, and cost. We need for large, pragmatic trials, enrolling heterogeneous populations of patients with depression to generate clinically relevant information on the benefits and harms of competitive pharmacological options. A meta-analysis of individual patient data from the randomised trials is clearly necessary.

Dose-response relationship of recent antidepressants in the short-term treatment of depression

Antidepressant drugs are widely recommended for the treatment of depressive disorders, and finding the "right dose for the right patient" is an important issue. Whatever antidepressant is prescribed, a proportion of adult patients with major depression fail to respond satisfactorily to adequate first-line treatment. A frequent strategy for patients with insufficient response to an initial antidepressant dose is to increase the dose. This review is about this strategy, ie, the possible benefits of prescribing higher doses of recent antidepressants. The results show that a flat dose-response curve is a class phenomenon for selective serotonin reuptake inhibitors (SSRIs), according to randomized, controlled, fixed-dose clinical trials. For the serotonin and noradrenaline reuptake inhibitors (SNRIs), the strategy of dose increase may be relevant for venlafaxine, in order to increase the number of responders. Thus, the subgroup of patients for whom high doses of SSRIs could be useful remains to be defined.

SNRIs: their pharmacology, clinical efficacy, and tolerability in comparison with other classes of antidepressants

The class of serotonin and norepinephrine reuptake inhibitors (SNRIs) now comprises three medications: venlafaxine, milnacipran, and duloxetine. These drugs block the reuptake of both serotonin (5-HT) and norepinephrine with differing selectivity. Whereas milnacipran blocks 5-HT and norepinephrine reuptake with equal affinity, duloxetine has a 10-fold selectivity for 5-HT and venlafaxine a 30-fold selectivity for 5-HT. All three SNRIs are efficacious in treating a variety of anxiety disorders. There is no evidence for major differences between SNRIs and SSRIs in their efficacy in treating anxiety disorders. In contrast to SSRIs, which are generally ineffective in treating chronic pain, all three SNRIs seem to be helpful in relieving chronic pain associated with and independent of depression. Tolerability of an SNRI at therapeutic doses varies within the class. Although no direct comparative data are available, venlafaxine seems to be the least well-tolerated, combining serotonergic adverse effects (nausea, sexual dysfunction, withdrawal problems) with a dose-dependent cardiovascular phenomenon, principally hypertension. Duloxetine and milnacipran appear better tolerated and essentially devoid of cardiovascular toxicity.

Remarkable effect of milnacipran, a serotonin-noradrenalin reuptake inhibitor (SNRI), on depressive symptoms in patients with Parkinson's disease who have insufficient response to selective serotonin reuptake inhibitors (SSRIs): two case reports

The authors present here two cases of Parkinson's disease with depression refractory to SSRIs treatment, who experienced a complete remission after replacing the ongoing SSRIs with a serotonin-noradrenalin reuptake inhibitor (SNRI), milnacipran. The case reports suggest that milnacipran may be one of the treatment options for depression in patients with Parkinson's disease who had inadequate response to SSRIs. Further studies are warranted to confirm this observation.

Lack of Interaction of Milnacipran with the Cytochrome P450 Isoenzymes Frequently Involved in the Metabolism of Antidepressants

OBJECTIVE

To compare the pharmacokinetics of milnacipran in extensive metabolisers (EMs) and poor metabolisers (PMs) of sparteine and mephenytoin, and to assess the influence of multiple administrations of milnacipran on the activity of cytochrome P450 (CYP) isoenzymes through its own metabolism and through various probes, namely CYP2D6 (sparteine/dextromethorphan), CYP2C19 (mephenytoin), CYP1A2 (caffeine) and CYP3A4 (endogenous 6-beta-hydroxy-cortisol excretion).

METHODS

Twenty-five healthy subjects, 12 EMs for both sparteine/dextromethorphan and mephenytoin, nine EMs for mephenytoin and PMs for sparteine/dextromethorphan (PM(2D6)) and four PMs for mephenytoin and EMs for sparteine/dextromethorphan (PM(2C19)) were administered milnacipran as a single 50 mg capsule on day 1 followed by a 50 mg capsule twice daily for 7 days. The pharmacokinetics of milnacipran and its oxidative metabolites were assessed after the first dose (day 1) and after multiple administration (day 8), and were compared for differences between CYP2D6 and CYP2C19 PMs and EMs. Metabolic tests were performed before (day -2), during (days 1 and 8) and after (day 20) milnacipran administration.

RESULTS

Milnacipran steady state was rapidly achieved. Metabolism was limited: approximately 50% unchanged drug, 30% as glucuronide and 20% as oxidative metabolite (mainly F2800 the N-dealkyl metabolite). Milnacipran administration to PM2D6 and PM2C19 subjects did not increase parent drug exposure or decrease metabolite exposure. Milnacipran oxidative metabolism is not mediated through CYP2D6 or CYP2C19 polymorphic pathways nor does it significantly interact with CYP1A2, CYP2C19, CYP2D6 or CYP3A4 activities.

CONCLUSION

Limited reciprocal pharmacokinetic interaction between milnacipran and CYP isoenzymes would confer flexibility in the therapeutic use of the drug when combined with antidepressants. Drug-drug interaction risk would be low, even if the combined treatments were likely to inhibit CYP2D6 and CYP2C19 isoenzyme activities.

International dosage differences in fluoxetine clinical trials

OBJECTIVE

International differences are thought to exist in dosages used by clinicians treating mood disorders. This study examined international dosage differences in antidepressant clinical trials, using a database formed and maintained as a component of a Cochrane review of comparative clinical trials of fluoxetine.

METHODS

This systematic review included 132 studies. A detailed set of methodological features and results were abstracted from the original publications and entered into an electronic database. Mean and maximum fluoxetine dosages were compared across countries. To evaluate the dosages of comparison medications, a defined daily dosage (DDD) ratio was calculated as the trial mean dosage divided by the DDD for that drug.

RESULTS

Both the maximum and mean dosages for fluoxetine and comparison medications were higher in trials conducted in the US (fluoxetine weighted mean dosage 49.18 mg; 95% CI, 41.30 to 57.05), compared with trials conducted in Europe (fluoxetine weighted mean dosage 29.98 mg; 95% CI, 25.28 to 34.68). Since most clinical trials were conducted in Europe or the US, we could not determine whether different dosages tended to be used in other regions.

CONCLUSIONS

International differences in prescriber behaviour may influence, and in turn be influenced by, the conduct of clinical trials. It is difficult to reconcile such differences with the principles of evidence-based medicine.

Controlled comparison of two different doses of milnacipran in major depressive outpatients

We compared the antidepressant efficacy and patient tolerance of two different doses of milnacipran (75 mg and 150 mg daily) in 66 outpatients with major depression, using the 17-item Hamilton Depression Rating Scale (HDRS). Only new patients who had never experienced frank depressive episodes before, or those who had remained free from thymoregulators for more than 1 year without recurrence of depressive symptoms, were recruited. Subjects were randomly selected to receive a daily dose of milnacipran that reached either 75 mg or 150 mg within 2-3 weeks and then remained stable over an 8-week period. The results showed a significant superiority of milnacipran at 150 mg/day over 75 mg/day at the end of the study period in both response (50% or more decrease in total score from baseline, P=0.026) and remission (total HDRS score lower than 7 points, P=0.034). A response was recorded for 56.0% of the patients treated with 75 mg of milnacipran and for 84.6% of those treated with 150 mg after the 8-week study period. No significant difference was seen between the treatment groups for either individual or total incidence of adverse events. Notably, nausea and vomiting occurred most often immediately after the first visit, when subjects in both groups started with a daily dose of 50 mg. We conclude that additional comparisons between different doses of milnacipran should be performed to confirm or deny the linear dose/efficacy relationship observed in the present study.

Comparaison de deux outils de mesure des effets indésirables d’un traitement antidépresseur : la notification spontanée et l’échelle UKU

BACKGROUND AND AIM OF THE STUDY

Overall, the efficacy of the newer antidepressants: serotonin selective reuptake inhibitors (SSRI), selective serotonin/norepinephrine reuptake inhibitor (SNRI), noradrenergic and specific serotonergic antidepressant (NaSSA) and tianeptine is similar to that of the tricyclics, and so their acceptability/safety becomes a selection criterion for the clinician. However, side-effect assessment comes up against several difficulties: distinguishing between somatic symptoms caused by the depression and those caused by the treatment -- which assessment tool to use (spontaneous notification, standardized scales that are not specific for the side effects caused by psychotropic drugs, standardised scales specific for the side effects caused by psychotropic drugs, meta-analysis, etc.) -- which data sources to consult (anecdotal reports, reviews, prospective studies), and which data set to use, etc. As a result, the question of the exhaustiveness and reliability of the data consulted by the clinician can arise. We therefore conducted a comparative study in patients treated with these newer antidepressants, of 2 antidepressants side-effect assessment tools: spontaneous notification (SN) versus the UKU scale, a standardised scale specific for the side effects of psychotropic drugs.

METHODOLOGY

The depressed outpatients were selected from a psychiatric unit in a French psychiatric hospital and from a non-hospital consulting room. The main inclusion criteria were: male or female subjects, suffering from major depression without melancholia or psychotic features or suffering from mood disorders (according to DSM IV criteria), who had been treated for at least 4 weeks with one of the newer antidepressants. The main exclusion criteria were: any other psychiatric disorder, a serious physical disorder, treatment with neuroleptics, mood-changing drugs or other antidepressants, and patients who were not able to understand the questionnaire. The investigation was carried out by a clinical pharmacist.

RESULTS

Fifty patients were included in the study. There were 18 men and 32 women. The mean age was 53.5 15.9 years [22 - 77], the mean period of treatment was 24 30.5 months [1 - 127] and 52% of the patients received concomitant medication with anxiolitic or hypnotic drug(s). The percentage of patients who reported at least one side effect was significantly higher for the UKU scale than for SN (84% vs 58%, p<0.01). The ratio between SN and UKU scale scores was 2/3. A similar pattern was found for the total number of side effects (n=177 vs n=47, p<0.001). The ratio between the total number of side effects for the SN and UKU scale was 1/4. The side effects were divided into five subgroups: psychiatric, neurovegetative, sexual, neurological and others. In all these subgroups, the number of side effects reported was significantly higher when the UKU scale was used than when SN was used. The values were as follows: psychiatric (n=44 vs n=15, p<0.001), neurovegetative (n=59 vs n=15, p<0.001), sexual (n=36 vs n=10, p<0.001), neurological (n=11 vs n=2, p<0.001) and other side effects (n=27 vs n=5, p<0.001). Nineteen side effects were only reported when SN was used (for example: dry eyes, incompatibility with alcohol, euphoria...). Twenty-four side effects were only reported when the UKU scale was used (for example: increased libido, loss of bodyweight...). The side effects had no impact on daily life in most of 80% of the patients; there was no significant difference between the patient's assessment of the discomfort caused by side effects and the clinician's assessment. In 90% of cases, the side effects did not lead to any change in the treatment.

DISCUSSION

The findings of this study show that the collection of data regarding side effects depends on the assessment tool used: the number of side effects reported was significantly higher when the UKU scale was used than when SN was used. However, this finding must viewed with caution, because it has been showed that checklists can induce symptoms in suggestible patients. Neurovegetative troubles are the most commonly reported side effects, and neurological troubles the least often reported. This matches the tolerability profile of these antidepressants. The disorders that were least frequently spontaneously reported were the neurological, sexual and "other" side effects. These emerged only when the clinician asked the patient about them. The 19 side effects that were only reported when SN was used were side effects that were not included in the UKU scale or that had not been present during the three days before we started the investigation. The 34 side effects that were only reported when the UKU scale was used were either side effects with no apparent link with the treatment (for example: micturition troubles) or embarrassing effects (such as increased libido).

CONCLUSION

Our findings show that the collection of data on side effects depends on the assessment tool used. These findings need to be confirmed by large-scale comparative studies, and the standardization of the assessment of side effects is a question that needs to be raised.

"Wish bias" in antidepressant drug trials?

The present study investigated whether the outcome of randomized clinical trials studying fluoxetine favored fluoxetine, where this was the experimental agent, and favored comparator antidepressants in trials where fluoxetine was the reference agent. A systematic review of all double-blind, randomized clinical trials comparing fluoxetine with any other antidepressant drug in patients suffering from depression was carried out. Thirty-seven studies meeting the inclusion criteria were analyzed. A metaregression analysis indicated that, after adjusting for possible confounders, studies where fluoxetine was the experimental agent were positively associated with treatment effect, indicating a significant advantage for fluoxetine. The evidence that the outcome of fluoxetine trials varied according to whether this drug was used as a new compound or a reference one suggests the presence of bias.

Dual monoamine modulation for improved treatment of major depressive disorder

The worldwide scope of depressive illness and lack of fully effective pharmacotherapy mandates significant improvements in treatment paradigms. Current antidepressant medications remain limited by poor efficacy, slow onset of action, and untoward side effects. While the introduction of serotoninspecific reuptake inhibitors (SSRIs) offered significant improvements in tolerability, no improvements in efficacy or speed of onset have been made relative to the traditional and poorly tolerated tricyclic antidepressants (TCA). The dominant efforts toward improving antidepressant medications are guided by cumulative evidence from neurochemical and clinical studies supporting the therapeutic potential of enhancing monoamine function in depression. A number of novel antidepressant drugs, including mirtazapine, milnacipran, venlafaxine, and duloxetine have been developed based on their interaction with both 5-HT and NE. Current clinical evidence suggests that these new agents may offer improved efficacy and/or faster onset of action compared with SSRIs and an improved side effect profile compared with TCAs. Potential neurobiological substrates mediating the enhanced antidepressant activity of dual reuptake inhibitors are discussed.

Dual serotonin and noradrenaline uptake inhibitor class of antidepressants potential for greater efficacy or just hype?

Preclinical and clinical studies support the rationale that development of single molecules, which would promote serotonergic and noradrenergic neurotransmission by inhibiting simultaneously the uptake of both monoamines, would potentially result in improved antidepressant drugs. Currently, the dual inhibitors of serotonin and noradrenaline uptake are venlafaxine, milnacipran and duloxetine. Based on the preclinical studies, the three drugs do show properties of inhibiting uptake of both monoamines in vitro and in vivo in the following order of decreasing potency: duloxetine, venlafaxine and milnacipran, and all exhibit low affinity at neuronal receptors of neurotransmitters, suggesting low side-effect potential. In double-blind, controlled studies, venlafaxine and milnacipran were repeatedly shown to be as efficacious as tricyclic antidepressant drugs in treating major depressive disorder, while one double-blind, placebo-controlled trial showed the antidepressant efficacy of duloxetine. Specifically designed comparative trials of dual uptake inhibitors against the other agents are needed to establish whether the dual uptake inhibitors show improvement in efficacy, rate of responders, antidepressive effects and/or remission.

Differential effects of milnacipran and fluvoxamine, especially in patients with severe depression and agitated depression: a case-control study

We attempted to compare the antidepressant efficacy of milnacipran and fluvoxamine in 202 outpatients with major depression, using the 17-item Hamilton Depression Rating Scale (HDRS). Special attention was paid to the difference of responsiveness as a function of the severity of depression and individual HDRS factors. As a result, while no significant difference between the treatment groups was found overall, a positive response (50% or more decrease in total score from the baseline) was recorded significantly more often with milnacipran than fluvoxamine recipients whose baseline HDRS total score was greater than 19 points. Furthermore, there was a significant difference of response for the 'agitation' and 'insomnia' factors in favour of milnacipran. In both treatment groups, the incidence of adverse events, characteristic of tricyclic antidepressants such as dry mouth, constipation, somnolence and postural hypotension, was low. While complaints concerning the upper intestinal tract, such as epigastric distress, were predominant in the fluvoxamine group, urological complications and palpitations were reported only in the milnacipran group. In conclusion, we suggest that milnacipran is preferred to selective serotonin reuptake inhibitors for the treatment of depressed patients with agitation as well as severely depressed patients.

Antidepressant efficacy and tolerability of milnacipran, a dual serotonin and noradrenaline reuptake inhibitor: a comparison with fluvoxamine

The antidepressant efficacy and tolerability of milnacipran, a dual action serotonin-noradrenaline reuptake inhibitor, were compared with those of the selective serotonin reuptake inhibitor, fluvoxamine, in 113 patients with moderate to severe major depression. Treatment with milnacipran, 50 mg b.d. for 6 weeks, produced a significantly greater reduction in Montgomery-Asberg Depression Rating Scale (MADRS) scores than fluvoxamine, 100 mg b.d. (P = 0.007; 65.4% versus 49.9%, respectively); significantly greater decreases were also seen on days 7 (P = 0.04) and 28 (P = 0.03). The response rate (the proportion of patients showing a decrease in MADRS scores of at least 50%) was 78.9% in patients receiving milnacipran, compared with 60.7% in fluvoxamine-treated patients (P = 0.04). Milnacipran also produced greater improvements in 24-item Hamilton Depression Rating Scale scores (P = 0.05). On the Clinical Global Impression Improvement scale, 77.2% of milnacipran-treated patients were rated as considerably or markedly improved, compared with 60.7% of patients receiving fluvoxamine (P = 0.06 chi-squared). Both treatments were well tolerated; the only significant difference between the two groups was a higher incidence of tremor and drowsiness in patients treated with fluvoxamine. It is concluded that milnacipran may offer some advantages over selective serotonin reuptake inhibitors, such as fluvoxamine, in the treatment of moderate to severe major depression.

Milnacipran: an antidepressant with dual selectivity of action on noradrenaline and serotonin uptake

Milnacipran is a new antidepressant which possesses potent and doubly selective action in that it inhibits both the re-uptake of serotonin and noradrenaline without any effect on other neurotransmitter systems. The almost equipotent inhibition of serotonin and noradrenaline by milnacipran is functionally reflected in the several-fold and long-lasting increase of the levels of these monoamines in the brain and in antidepressant-like effects in animals. In man, milnacipran distinguishes itself from many other antidepressants by its simple pharmacokinetics. It shows linear dose-concentration relationship over a dose range of 25-200 mg/day. It is rapidly and extensively absorbed and almost completely eliminated after 12 h (t1/2 approx. 8 h). Steady-state plasma levels are reached within 32-48 h after twice daily oral administration. Milnacipran is highly bioavailable (>85 per cent) and its metabolism does not involve the cytochrome P450 enzyme system. In clinical studies, milnacipran showed antidepressant efficacy similar to that of TCAs and SSRIs and superior to that of placebo. At the optimum dose of 100 mg/day, after 4-8 weeks of treatment, 60-64 per cent of in- or out-patients with major depression improve (>/=50 per cent reduction of HAMD and MADRS score) and about 32-39 per cent of them achieve full remission (HAMD score</=7). Milnacipran has proved to be a very safe drug with a benign adverse event profile clearly superior to that of TCAs and, to a certain extent, that of SSRIs. Only about 10 per cent of patients experience side-effects and only dysuria occurred more frequently (2 per cent) with milnacipran than with TCAs or SSRIs. Milnacipran appears therefore to be an antidepressant with a very favourable benefit/risk ratio. Copyright 2000 John Wiley & Sons, Ltd.

Novel strategies for pharmacotherapy of depression

Modulating monoamine activity as a therapeutic strategy continues to dominate antidepressant research, with a recent emphasis on agents with multiple targets, including combined serotonin/noradrenaline re-uptake inhibitors and numerous serotonin receptor ligands. An important new development has been the emergence of potential novel mechanisms of action, notably modulation of the activity of neuropeptides substance P and corticotrophin-releasing factor, and the intracellular messenger cyclic adenosine monophosphate. Efforts in this area have recently been rewarded by the demonstration of antidepressant efficacy of the substance P receptor antagonist MK-0869.