Frequency of positive studies among fixed and flexible dose antidepressant clinical trials: an analysis of the food and drug administration summary basis of approval reports

CYP2D6 P34S Polymorphism and Outcomes of Escitalopram Treatment in Koreans with Major Depression

OBJECTIVE

Cytochrome P450 (CYP) enzymatic activity, which is influenced by CYP genetic polymorphism, is known to affect the inter-individual variation in the efficacy and tolerability of antidepressants in major depressive disorder (MDD). Escitalopram is metabolized by CYP2D6, and recent studies have reported a correlation between clinical outcomes and CYP2D6 genetic polymorphism. The purpose of this study was to determine the relationship between the CYP2D6 P34S polymorphism (C188T, rs1065852) and the efficacy of escitalopram treatment in Korean patients with MDD.

METHODS

A total of 94 patients diagnosed with MDD were recruited for the study and their symptoms were evaluated using the 21-item Hamilton Depression Rating scale (HAMD-21). The association between the CYP2D6 P34S polymorphism and the clinical outcomes (remission and response) was investigated after 1, 2, 4, 8, and 12 weeks of escitalopram treatment using multiple logistic regression analysis and χ(2) test.

RESULTS

The proportion of P allele carriers (PP, PS) in remission status was greater than that of S allele homozygotes (SS) after 8 and 12 weeks of escitalopram treatment. Similarly, P allele carriers exhibited a greater treatment response after 8 and 12 weeks of escitalopram treatment than S allele homozygotes.

CONCLUSION

Our results suggest that the P allele of the CYP2D6 P34S polymorphism is a favorable factor in escitalopram treatment for MDD, and that the CYP2D6 P34S polymorphism may be a good genetic marker for predicting escitalopram treatment outcomes.

Does adding noradrenaline reuptake inhibition to selective serotonin reuptake inhibition improve efficacy in patients with depression? A systematic review of meta-analyses and large randomised pragmatic trials

Selective serotonin reuptake inhibitors (SSRIs) are recommended as first-line pharmacological treatment for depression and are the most commonly prescribed class of antidepressants. However, there is substantial evidence that noradrenaline has a role in the pathogenesis and treatment of depression. This review aims to examine the evidence of including noradrenaline reuptake inhibition with serotonin reuptake inhibition with respect to increasing efficacy in the treatment of depression. Evidence from meta-analysis of randomised controlled trials (RCTs) and randomised pragmatic trials was found in support of greater efficacy of the serotonin noradrenaline reuptake inhibitors (SNRIs), venlafaxine and duloxetine, in moderate to severe depression compared to SSRIs but no evidence was found for superiority of milnacipran. There is sufficient current evidence that demonstrates an increase in efficacy, when noradrenaline reuptake is added to serotonin (5-HT) reuptake, to suggest that patients with severe depression or those who have failed to reach remission with a SSRI may benefit from treatment with a SNRI. However, as these conclusions are drawn from the evidence derived from meta-analyses and pragmatic trials, large adequately powered RCTs using optimal dosing regimens and clinically relevant outcome measures in severe depression and SSRI treatment failures are still required to confirm these findings.

A comparative analysis between site-based and centralized ratings and patient self-ratings in a clinical trial of Major Depressive Disorder

We compared scores from three different ratings methods in a clinical trial of patients with Major Depressive Disorder (MDD). The Quick Inventory of Depressive Symptoms (QIDS-SR16) was compared to site-based clinician and centralized (site-independent) ratings of the Inventory of Depressive Symptoms (IDSc30). An extracted QIDSc16 was used for a matched comparison with the QIDS-SR16. Patient self-ratings were more depressed at baseline than either site-based ratings (p = 0.131) or centralized ratings (p = 0.005), but significantly less depressed at the end of double-blind treatment than either site-based (p = 0.006) or centralized ratings (p = 0.014), and after 12 weeks (site-based ratings: p = 0.048; centralized ratings: p = 0.004). The matched comparisons with patient self-ratings revealed ICC of r = 0.55 (site-based raters) and r = 0.49 (centralized raters) at baseline. After baseline, the correlations between the two different clinician ratings and patient self-ratings improved to r-values between 0.78 and 0.89. At the end of double-blind treatment, site-based raters separated the combination treatment from placebo on the IDSc30 (p = 0.030) whereas neither centralized ratings nor patient self-ratings achieved statistical significance. Alternatively, patient self-ratings separated the combination treatment from buspirone (p = 0.030) whereas neither clinician rating method achieved significance. A "dual" scoring concordance range reduced the placebo response rate and increased the drug effect between the combination treatment and placebo. These findings reveal scoring variability between each of the three ratings methods and challenge the reliability of any single method to accurately assess symptom severity scores, particularly at baseline. The use of "dual" scoring criteria may help to confirm symptom severity scores and improve ratings precision, particularly prior to enrolling subjects into CNS trials.

A randomized, double-blind trial of 2.5 mg and 5 mg vortioxetine (Lu AA21004) versus placebo for 8 weeks in adults with major depressive disorder

OBJECTIVE

Vortioxetine (Lu AA21004) is an investigational antidepressant. In vitro studies indicate that vortioxetine is a 5-HT(3), 5-HT(7), and 5-HT(1D) receptor antagonist, 5-HT(1B) receptor partial agonist, 5-HT(1A) receptor agonist and inhibitor of the 5-HT transporter. This trial assessed the efficacy and tolerability of 2.5 and 5 mg vortioxetine for the treatment of MDD.

RESEARCH DESIGN AND METHODS

Adults (N = 611) with MDD were randomized to 8 weeks of double-blind treatment with placebo, vortioxetine (2.5 or 5 mg) or active reference (duloxetine 60 mg). The primary measure was change from baseline in the 24-item Hamilton Depression Scale (HAM-D24). Secondary endpoints included responder rate, Clinical Global Impression Scale-Global Improvement scale (CGI-I), and remission rate. Participants were monitored for adverse events (AEs), and treatment-emergent sexual dysfunction using the Arizona Sexual Experiences (ASEX) scale.

RESULTS

Both doses of vortioxetine were associated with declines in HAM-D24 total scores compared to placebo but were not statistically significant. At 8 weeks, changes from baseline were [mean (SE)]: -10.50 (0.76) placebo, -12.04 (0.74) 2.5 mg vortioxetine, and -11.08 (0.74) 5 mg vortioxetine. Secondary outcome measures in the vortioxetine groups, including responder rate, CGI-I, and remission rate, were also not significantly different from placebo. Duloxetine treatment was associated with declines in HAM-D24 total score [-13.47(0.75); p = 0.005] as well as significant improvements in secondary outcome measures versus placebo (p ≤ 0.05). The most common AEs for vortioxetine were nausea, dry mouth, and headache. Rates of sexual dysfunction (ASEX) were 51.0%, 37.5%, 46.9%, and 33.3% in the vortioxetine 2.5 mg, vortioxetine 5 mg, duloxetine, and placebo groups, respectively.

CONCLUSIONS

In this study of adults with MDD treated for 8 weeks with vortioxetine 2.5 mg or 5 mg per day, reductions in depression symptoms were not statistically significant compared with placebo. Study limitations are discussed, including patient characteristics, MDD severity, drug dosing, and aspects of trial design. Both doses of vortioxetine were well tolerated. This trial has been registered at clinicaltrials.gov #NCT00672620.

Low-dose vaporized cannabis significantly improves neuropathic pain

We conducted a double-blind, placebo-controlled, crossover study evaluating the analgesic efficacy of vaporized cannabis in subjects, the majority of whom were experiencing neuropathic pain despite traditional treatment. Thirty-nine patients with central and peripheral neuropathic pain underwent a standardized procedure for inhaling medium-dose (3.53%), low-dose (1.29%), or placebo cannabis with the primary outcome being visual analog scale pain intensity. Psychoactive side effects and neuropsychological performance were also evaluated. Mixed-effects regression models demonstrated an analgesic response to vaporized cannabis. There was no significant difference between the 2 active dose groups' results (P > .7). The number needed to treat (NNT) to achieve 30% pain reduction was 3.2 for placebo versus low-dose, 2.9 for placebo versus medium-dose, and 25 for medium- versus low-dose. As these NNTs are comparable to those of traditional neuropathic pain medications, cannabis has analgesic efficacy with the low dose being as effective a pain reliever as the medium dose. Psychoactive effects were minimal and well tolerated, and neuropsychological effects were of limited duration and readily reversible within 1 to 2 hours. Vaporized cannabis, even at low doses, may present an effective option for patients with treatment-resistant neuropathic pain.

PERSPECTIVE

The analgesia obtained from a low dose of delta-9-tetrahydrocannabinol (1.29%) in patients, most of whom were experiencing neuropathic pain despite conventional treatments, is a clinically significant outcome. In general, the effect sizes on cognitive testing were consistent with this minimal dose. As a result, one might not anticipate a significant impact on daily functioning.

Study design features affecting outcome in antidepressant trials

BACKGROUND

A key issue in the approval process of antidepressants is the inconsistency of results between antidepressant clinical phase III trials. Identifying factors influencing efficacy data is needed to facilitate interpretation of the results.

METHODS

We reviewed data packages submitted as new drug applications to Swissmedic focusing on pivotal, short-term antidepressant trials. Included studies used HAMD-17 or HAMD-21 as primary measures and enrolled patients aged 18-65 years with a diagnosis of major depression. Due to the hierarchical structure of the data a mixed-effect regression model has been applied with responder rates as primary outcome criterion. Random intercepts were estimated for the different trials, while study design factors were assigned as explanatory fixed effects.

RESULTS

The final dataset was based upon 35 study reports with a total of N=10,835 patients. Significant results were found for study arm (placebo vs. active compound, p<0.001), sample size (p=0.002), duration of treatment (p=0.024), two or more active treatment arms (p=0.022) and the individual drug (p=0.029). Furthermore, a tendency to an association with the outcome was observed for baseline disease severity (p=0.077) and possibility of dosing adaptation (p=0.076).

LIMITATIONS

Due to strict confidentiality agreements, individual drugs are not reported here. Further research should consider additional variables that might have an impact on the results of antidepressant trials.

CONCLUSIONS

Efficacy data in antidepressant trials is significantly affected by various factors. These factors and their potentially confounding role have to be considered in the interpretation of the results.

Duloxetine versus other anti-depressive agents for depression

BACKGROUND

Although pharmacological and psychological interventions are both effective for major depression, in primary and secondary care settings antidepressant drugs remain the mainstay of treatment. Amongst antidepressants many different agents are available. Duloxetine hydrochloride is a dual reuptake inhibitor of serotonin and norepinephrine and has been licensed by the Food and Drug Administration in the US for major depressive disorder (MDD), generalised anxiety disorder, diabetic peripheral neuropathic pain, fibromyalgia and chronic musculoskeletal pain.

OBJECTIVES

To assess the evidence for the efficacy, acceptability and tolerability of duloxetine in comparison with all other antidepressant agents in the acute-phase treatment of major depression.

SEARCH METHODS

MEDLINE (1966 to 2012), EMBASE (1974 to 2012), the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register and the Cochrane Central Register of Controlled Trials up to March 2012. No language restriction was applied. Reference lists of relevant papers and previous systematic reviews were hand-searched. Pharmaceutical company marketing duloxetine and experts in this field were contacted for supplemental data.

SELECTION CRITERIA

Randomised controlled trials allocating patients with major depression to duloxetine versus any other antidepressive agent.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and a double-entry procedure was employed. Information extracted included study characteristics, participant characteristics, intervention details and outcome measures in terms of efficacy, acceptability and tolerability.

MAIN RESULTS

A total of 16 randomised controlled trials (overall 5735 participants) were included in this systematic review. Of these, three trials were unpublished. We found 11 studies (overall 3304 participants) comparing duloxetine with one selective serotonin reuptake inhibitor (SSRI) (six studies versus paroxetine, three studies versus escitalopram and two versus fluoxetine), four studies (overall 1978 participants) comparing duloxetine with a newer antidepressants (three with venlafaxine and one with desvenlafaxine, respectively) and one study (overall 453 participants) comparing duloxetine with an antipsychotic drug which is also used as an antidepressive agent, quetiapine. No studies were found comparing duloxetine with tricyclic antidepressants. The pooled confidence intervals were rather wide and there were no statistically significant differences in efficacy when comparing duloxetine with other antidepressants. However, when compared with escitalopram or venlafaxine, there was a higher rate of drop out due to any cause in the patients randomised to duloxetine (odds ratio (OR) 1.62; 95% confidence interval (CI) 1.01 to 2.62 and OR 1.56; 95% CI 1.14 to 2.15, respectively). There was also some weak evidence suggesting that patients taking duloxetine experienced more adverse events than paroxetine (OR 1.24; 95% CI 0.99 to 1.55).

AUTHORS' CONCLUSIONS

Duloxetine did not seem to provide a significant advantage in efficacy over other antidepressive agents for the acute-phase treatment of major depression. No differences in terms of efficacy were found, even though duloxetine was worse than some SSRIs (most of all, escitalopram) and newer antidepressants (like venlafaxine) in terms of acceptability and tolerability. Unfortunately, we only found evidence comparing duloxetine with a handful of other active antidepressive agents and only a few trials per comparison were found (in some cases we retrieved just one trial). This limited the power of the review to detect moderate, but clinically meaningful differences between the drugs. As many statistical tests have been used in the review, the findings from this review are better thought of as hypothesis forming rather than hypothesis testing and it would be very comforting to see the conclusions replicated in future trials. Most of included studies were sponsored by the drug industry manufacturing duloxetine. As for all other new investigational compounds, the potential for overestimation of treatment effect due to sponsorship bias should be borne in mind. In the present review no trials reported economic outcomes. Given that several SSRIs and the great majority of antidepressants are now available as generic formulation (only escitalopram, desvenlafaxine and duloxetine are still on patent), more comprehensive economic estimates of antidepressant treatment effect should be considered to better inform healthcare policy.

Increasing trial efficiency by early reallocation of placebo nonresponders in sequential parallel comparison designs: Application to antidepressant trials

Background

The sequential parallel comparison (SPC) design was proposed to improve the efficiency of psychiatric clinical trials by reducing the impact of placebo response. It consists of two consecutive placebo-controlled comparisons of which the second is only entered by placebo nonresponders from the first. Previous studies suggest that in antidepressant trials, nonresponse to placebo can already be predicted after 2 weeks of follow-up. This would allow to reduce the first phase of the SPC design to further increase its efficiency.

Purpose

To compare the sample size requirements of an 8-week randomized controlled trial (RCT8) and alternative SPC designs with equal or longer total follow-up duration (SPC2+6, SPC4+4, and SPC6+6).

Methods

Scenarios for response and dropout rates were defined. Sample sizes to achieve 80% power were determined for the various designs. Three treatment functions assumed either a smaller, equal, or larger effect at the early stage of the trial as compared with that at the end. Two dropout models described either predominantly early or linearly increasing dropout, and dropout was considered as nonresponse. The relative efficiency of the different designs was evaluated across these scenarios and for a specific scenario based on empirical antidepressant trial data.

Results

The different SPC designs (i.e., SPC2+6, SPC4+4, and SPC6+6) were generally more efficient than the RCT8 design when the treatment effect at the early stage of the trial was equal or larger than the effect at the end. In this case, the advantage of the SPC designs increased in the presence of dropout. The SPC2+6 design was usually more efficient than the SPC4+4 design and was relatively less affected by dropout when it occurred predominantly early. For the scenario that was based on antidepressant trial data, the SPC2+6 and SPC4+4 designs required 51% and 53% fewer patients than the RCT8 design.

Limitations

A limited variety of scenarios was evaluated. Parameter values resembled those observed in antidepressant trials.

Conclusions

This study suggests that SPC designs are highly efficient alternatives to a conventional RCT in indications where placebo response is high and substantial treatment effects are established after a relatively short follow-up period (i.e., after the first SPC design phase). We conclude that SPC designs can reduce sample size requirements and increase success rates of antidepressant trials.

Efficacy of duloxetine on painful physical symptoms in major depressive disorder for patients with clinically significant painful physical symptoms at baseline: a meta-analysis of 11 double-blind, placebo-controlled clinical trials

OBJECTIVE

To review efficacy of duloxetine for physical symptoms and depressive illness in patients with at least mild to moderate major depressive disorder (MDD; DSM-IV) and clinically significant painful physical symptoms at baseline.

DATA SOURCES

Global database of duloxetine clinical trials (Eli Lilly and Company).

STUDY SELECTION

All 11 acute, double-blind, placebo-controlled studies of duloxetine (7 with duloxetine 60-mg doses and 4 with non-60-mg doses) in the database that used a scale to measure painful physical symptoms and were completed before March 17, 2011.

DATA EXTRACTION

For each study, patients with clinically significant pain levels at baseline (Visual Analog Scale overall pain rating ≥ 30, Numerical Rating Scale score ≥ 3, or Brief Pain Inventory 24-hour average pain rating ≥ 3) were selected in order to determine the effect sizes of duloxetine (compared with placebo for each trial) on the pain and depression measures. Overall effect sizes for both painful physical symptoms and MDD were obtained from the mean of individual-trial effect sizes, and each effect size was weighted relative to the number of patients within each study.

DATA SYNTHESIS

The overall mean effect sizes were as follows: painful physical symptoms-60-mg trials, 0.29 (95% CI, 0.06 to 0.52); non-60-mg trials, 0.13 (95% CI, -0.19 to 0.45); MDD-60-mg trials, 0.29 (95% CI, 0.18 to 0.40); non-60-mg trials, 0.16 (95% CI, 0.00 to 0.32). Across the 11 studies, the weighted effect size for painful physical symptoms was 0.26 (95% CI, 0.00 to 0.51) and for MDD, 0.25 (95% CI, 0.16 to 0.34).

CONCLUSIONS

According to this meta-analysis, duloxetine 60 mg once daily is as effective in improving painful physical symptoms as it is for depression in patients with MDD and clinically significant painful physical symptoms. The results of this meta-analysis indicate that duloxetine has small effect sizes in reducing painful physical symptoms and depressive symptoms in patients with MDD and clinically significant pain levels at baseline. Thus, the results of the study permit one to conclude that duloxetine has a clinically significant impact on painful physical symptoms and in reducing the severity of depressive symptoms. However, the results do not address its efficacy compared to other alternatives, as in all studies the comparator was placebo.

Citalopram versus other anti-depressive agents for depression

BACKGROUND

Recent US and UK clinical practice guidelines recommend that second-generation antidepressants should be considered amongst the best first-line options when drug therapy is indicated for a depressive episode. Systematic reviews have already highlighted some differences in efficacy between second-generation antidepressants. Citalopram, one of the first selective serotonin reuptake inhibitors (SSRI) introduced in the market, is one of these antidepressant drugs that clinicians use for routine depression care.

OBJECTIVES

To assess the evidence for the efficacy, acceptability and tolerability of citalopram in comparison with tricyclics, heterocyclics, other SSRIs and other conventional and non-conventional antidepressants in the acute-phase treatment of major depression.

SEARCH METHODS

We searched The Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register and the Cochrane Central Register of Controlled Trials up to February 2012. No language restriction was applied. We contacted pharmaceutical companies and experts in this field for supplemental data.

SELECTION CRITERIA

Randomised controlled trials allocating patients with major depression to citalopram versus any other antidepressants.

DATA COLLECTION AND ANALYSIS

Two reviewers independently extracted data. Information extracted included study characteristics, participant characteristics, intervention details and outcome measures in terms of efficacy (the number of patients who responded or remitted), patient acceptability (the number of patients who failed to complete the study) and tolerability (side-effects).

MAIN RESULTS

Thirty-seven trials compared citalopram with other antidepressants (such as tricyclics, heterocyclics, SSRIs and other antidepressants, either conventional ones, such as mirtazapine, venlafaxine and reboxetine, or non-conventional, like hypericum). Citalopram was shown to be significantly less effective than escitalopram in achieving acute response (odds ratio (OR) 1.47, 95% confidence interval (CI) 1.08 to 2.02), but more effective than paroxetine (OR 0.65, 95% CI 0.44 to 0.96) and reboxetine (OR 0.63, 95% CI 0.43 to 0.91). Significantly fewer patients allocated to citalopram withdrew from trials due to adverse events compared with patients allocated to tricyclics (OR 0.54, 95% CI 0.38 to 0.78) and fewer patients allocated to citalopram reported at least one side effect than reboxetine or venlafaxine (OR 0.64, 95% CI 0.42 to 0.97 and OR 0.46, 95% CI 0.24 to 0.88, respectively).

AUTHORS' CONCLUSIONS

Some statistically significant differences between citalopram and other antidepressants for the acute phase treatment of major depression were found in terms of efficacy, tolerability and acceptability. Citalopram was more efficacious than paroxetine and reboxetine and more acceptable than tricyclics, reboxetine and venlafaxine, however, it seemed to be less efficacious than escitalopram. As with most systematic reviews in psychopharmacology, the potential for overestimation of treatment effect due to sponsorship bias and publication bias should be borne in mind when interpreting review findings. Economic analyses were not reported in the included studies, however, cost effectiveness information is needed in the field of antidepressant trials.

Joint modeling of efficacy, dropout, and tolerability in flexible-dose trials: a case study in depression

Many difficulties may arise during the modeling of the time course of Hamilton Rating Scale for Depression (HAM D)scores in clinical trials for the evaluation of antidepressant drugs: (i) flexible designs, used to increase the chance of selecting more efficacious doses, (ii) dropout events, and (iii) adverse effects related to the experimental compound.It is crucial to take into account all these factors when designing an appropriate model of the HAM D time course and to obtain a realistic description of the dropout process. In this work, we propose an integrated approach to the modeling of a double-blind, flexible-dose, placebo-controlled, phase II depression trial that comprises response,tolerability, and dropout. We investigate three different dropout mechanisms in terms of informativeness. Goodness of fit is quantitatively assessed with respect to response (HAM D score) and dropout data. We show that dropout is a complex phenomenon that may be influenced by HAM D evolution, dose changes, and occurrence of drug-related adverse effects.

Evaluation of the efficacy and safety of paliperidone extended-release in the treatment of acute mania: a randomized, double-blind, dose-response study

BACKGROUND

Atypical antipsychotics are effective in the treatment of bipolar I disorder. In this 3-week double-blind study, the efficacy and safety of paliperidone extended-release (ER) tablets were assessed in patients with acute mania.

METHODS

Patients experiencing a manic or mixed episode (Young Mania Rating Scale [YMRS] total score ≥20), were randomly assigned to 1 of 3 fixed doses of once-daily paliperidone ER (3, 6, or 12-mg), or placebo (1:1:1:1 ratio).

RESULTS

In total, 469 patients were randomly assigned to treatment with paliperidone ER 3mg (n=112), 6 mg (n=120), or 12 mg (n=115); or placebo (n=122). Mean (SD) change in YMRS total score from baseline to the 3-week endpoint (primary variable) was statistically significantly different for the paliperidone ER 12 mg group (-13.5 [9.17], p=0.025), but not the 6 mg (-11.4 [9.98], p=0.57) or 3mg (-9.1 [11.18], p=0.79) groups compared with placebo (-10.1 [10.21]). Headache was the most common treatment-emergent adverse event (17% total paliperidone ER versus 12% placebo).

LIMITATIONS

A statistically significant (p=0.0032) treatment-by-country interaction occurred, which confounded interpretation of study results. Paliperidone ER and placebo did not differ statistically for the primary efficacy variable among patients from the United States sites (74% of the intent-to-treat analysis set).

CONCLUSIONS

Paliperidone ER 12 mg/day was superior to placebo in the treatment of acute mania. Change from baseline in YMRS total score increased with the dose of paliperidone ER. Paliperidone ER was generally tolerated by patients with bipolar I disorder and no new safety signal was detected.

Estimation of treatment effect for the sequential parallel design

The sequential parallel clinical trial is a novel clinical trial design being used in psychiatric diseases that are known to have potentially high placebo response rates. The design consists of an initial parallel trial of placebo versus drug augmented by a second parallel trial of placebo versus drug in the placebo non-responders from the initial trial. Statistical research on the design has focused on hypothesis tests. However, an equally important output from any clinical trial is the estimate of treatment effect and variability around that estimate. In the sequential parallel trial, the most important treatment effect is the effect in the overall population. This effect can be estimated by considering only the first phase of the trial, but this ignores useful information from the second phase of the trial. We develop estimates of treatment effect that incorporate data from both phases of the trial. Our simulations and a real data example suggest that there can be substantial gains in precision by incorporating data from both phases. The potential gains appear to be greatest in moderate-sized trials, which would typically be the case in phase II trials.

Duloxetine in the acute and continuation treatment of major depressive disorder

Duloxetine is a serotonin-noradrenaline reuptake inhibitor with indications for use in the short term, continuation and maintenance treatment of major depression. Although clinicians currently have access to a range of medications for the treatment of depression, a significant number of patients fail to respond or remit from their illness despite adequate trials of treatment with multiple agents. A developing concept is that antidepressant strategies that combine multiple mechanisms of action may have advantages over agents with single mechanisms (i.e., selective serotonin reuptake inhibitors). As a dual-acting agent, duloxetine offers the promise of advantages in terms of efficacy over selective serotonin reuptake inhibitors while retaining a favorable safety and tolerability profile in comparison to older agents. Likewise, duloxetine is of interest in the treatment of certain conditions commonly seen in conjunction with major depression, particularly anxiety and pain, both of which may respond more favorably to agents that act on both serotonin and noradrenaline neurotransmitter systems.

Recent developments in improving signal detection and reducing placebo response in psychiatric clinical trials

Recent (2007-2010) empirical and theoretical literature on associations of trial design features with signal detection and placebo response were investigated, along with data and analytic considerations. Trials with greater percentages of patients randomized to placebo had larger average drug-placebo differences in two comprehensive meta-analyses (MDD and Schizophrenia). Excluding patients with large responses during double-blind placebo lead-ins resulted in small increases in drug-placebo differences. Core factor subscales of the HAMD yielded larger drug-placebo differences than the HAMD total score. Direct likelihood-based (MMRM) and similar analyses provided better control of false positive and false negative results than LOCF and BOCF. Theoretical considerations suggested that the number of sites and number of countries can influence power, depending on the correlation structure in the data and on how sites and countries are chosen. Use of centralized ratings reduced placebo response and improved drug-placebo differences. However, the number of comparisons was too small to draw conclusions. Use of patient ratings and reducing the number of study visits reduced placebo response, but their effects on signal detection were unclear. Practical experience with novel designs such as the sequential parallel approach hold promise for improvements in signal detection. Given the complexities of signal detection and placebo response, no single strategy is likely to fully solve the problem and combinations of approaches may be most useful. Utilizing appropriate analytic techniques and randomizing an adequate fraction of patients to placebo are perhaps the most broadly applicable approaches.

Antidepressant treatment and altered CYP2D6 activity: are pharmacokinetic variations clinically relevant?

BACKGROUND

Many currently used antidepressants are substrates of the cytochrome P450 (CYP) 2D6 enzyme. In patients who experience variations in the activity of this enzyme (e.g., CYP2D6 poor and ultrarapid metabolizers [PMs and UMs]), whether caused by genetic polymorphisms or concomitant administration of a CYP2D6 inhibitor (i.e., phenoconversion), the pharmacokinetics, and hence the effects, of CYP2D6 substrate antidepressants can be altered.

METHODS

This literature review describes the clinical and empirical evidence indicating that alterations in CYP2D6 activity can negatively affect treatment outcomes in patients receiving antidepressant pharmacotherapies that are CYP2D6 substrates.

RESULTS

Based on results from a small, prospective trial, a population analysis, and a pooled analysis, CYP2D6 PMs treated with agents dependent on CYP2D6 metabolism to form an active metabolite can experience a decline in antidepressant effect. Based on a population analysis and two case studies, CYP2D6 UMs treated with antidepressants that are CYP2D6 substrates and administered in a pharmacologically active form do not experience an antidepressant effect due to the agent being too rapidly eliminated from the body. Conversely, based on prospective trials, population analyses, and case studies, phenotypic and phenoconverted CYP2D6 PMs can experience an increase in concentration-dependent adverse events due to the agent being eliminated too slowly from the body.

CONCLUSIONS

Despite these examples, few large-scale, prospective trials exploring the effect of altered CYP2D6 metabolism on antidepressant outcomes have been conducted. Future clinical trials of CYP2D6-dependent antidepressants should be designed to allow for stratification of treatment outcomes by CYP2D6 metabolizer status.

Do early changes in the HAM-D-17 anxiety/somatization factor items affect the treatment outcome among depressed outpatients? Comparison of two controlled trials of St John's wort (Hypericum perforatum) versus a SSRI

To assess whether early changes in Hamilton Depression Rating Scale-17 anxiety/somatization items predict remission in two controlled studies of Hypericum perforatum (St John's wort) versus selective serotonin reuptake inhibitors for major depressive disorder. The Hypericum Depression Trial Study Group (National Institute of Mental Health) randomized 340 patients to Hypericum, sertraline, or placebo for 8 weeks, whereas the Massachusetts General Hospital study randomized 135 patients to Hypericum, fluoxetine, or placebo for 12 weeks. The investigators examined whether remission was associated with early changes in anxiety/somatization symptoms. In the National Institute of Mental Health study, significant associations were observed between remission and early improvement in the anxiety (psychic) item (sertraline arm), somatic (gastrointestinal item; Hypericum arm), and somatic (general) symptoms (placebo arm). None of the three treatment arms of the Massachusetts General Hospital study showed significant associations between anxiety/somatization symptoms and remission. When both study samples were pooled, we found associations for anxiety (psychic; selective serotonin reuptake inhibitors arm), somatic (gastrointestinal), and hypochondriasis (Hypericum arm), and anxiety (psychic) and somatic (general) symptoms (placebo arm). In the entire sample, remission was associated with the improvement in the anxiety (psychic), somatic (gastrointestinal), and somatic (general) items. The number and the type of anxiety/somatization items associated with remission varied depending on the intervention. Early scrutiny of the Hamilton Depression Rating Scale-17 anxiety/somatization items may help to predict remission of major depressive disorder.

Vilazodone for the Treatment of Depression

Objective:

To evaluate the clinical literature on and potential clinical role of vilazodone for the treatment of major depressive disorder.

Data Sources:

Searches were conducted on MEDLINE (1948-February 2011), Iowa Drug Information Service (1988-February 2011), EBSCO Academic Search Premier (1975-February 2011), Google Scholar (1992-February 2011), PsycINFO (1980-February 2011), and PsycARTICLES (1985-February 2011), and on general Internet search engines including Google and Bing (no lower limit-February 2011). Search terms were vilazodone, EMD 68843, depression, and major depressive disorder. Potential prior marketers of vilazodone, including Merck KGaA in Germany and Genaissance Pharmaceuticals, were contacted for any available unpublished Phase 1, Phase 2, Phase 3 studies, or preclinical information.

Study Selection and Data Extraction:

All applicable full-text English-language articles, abstracts, and professional poster presentations found were evaluated and included in the review, as well as marketing and Securities and Exchange Commission filings available from the patent holders.

Data Synthesis:

Vilazodone is an antidepressant recently approved by the Food and Drug Administration (FDA) that is first in a new class regarding mechanism of action. It has demonstrated efficacy in the primary outcome of the Montgomery-Asberg Depression Rating Scale (MADRS) response in an 8-week pivotal Phase 3 trial. Phase 2 trials did not demonstrate efficacy for primary outcomes of the 17-item Hamilton Rating Scale for Depression but showed statistically significant improvements in select secondary outcomes such as Clinical Global Impressions severity and MADRS. Long-term efficacy data are still forthcoming. An emerging aspect to vilazodone's development has been the identification and assessment of potential genetic biomarkers associated with both therapeutic response and more serious adverse effects. Initial studies into biomarkers have been inconclusive.

Conclusions:

Vilazodone is a new agent recently approved by the FDA for treating major depressive disorder. Response rates seen with vilazodone are similar to those of currently available antidepressants.

Relationship between probability of receiving placebo and probability of prematurely discontinuing treatment in double-blind, randomized clinical trials for MDD: a meta-analysis

An increased likelihood of receiving placebo in randomized clinical trials has been found to predict greater chances of trial success. However, patients who are less likely to receive active therapy (and more likely to receive placebo) may be at increased risk of attrition which, in turn, can limit the statistical power of a study. Therefore, in the present work, we sought to investigate the relationship between the probability of receiving placebo and the likelihood of prematurely discontinuing treatment. Medline/Pubmed publication databases were searched for RCT in MDD. A meta-regression established that the likelihood of receiving placebo did not predict either antidepressant discontinuation rates, placebo-discontinuation rates or the risk ratio of discontinuing antidepressants versus placebo. An increased likelihood of receiving placebo did not inflate discontinuation rates which did not influence the degree of antidepressant-placebo "separation".

Meta-analysis of relapse prevention antidepressant trials in depressive disorders

OBJECTIVE

Continuation therapy with antidepressants is recommended for depressed patients who have responded to initial treatment. We quantified its efficacy in preventing relapse of depression in a meta-analysis of 54 double-blind placebo-controlled relapse prevention studies (patient n = 9268).

METHOD

Relapse prevention studies in primary depression and depression subtypes were identified in a systematic literature search. The primary efficacy comparison was relapse rates between active and placebo arms calculated as odds ratios (ORs) using Review Manager version 5.0. Effects of patient age, drug class, diagnostic system and duration of therapy on ORs was examined, along with ORs calculated using different statistical methods.

RESULTS

Continuation antidepressants produced robust reduction in relapse (OR = 0.35; 95%CI 0.32-0.39). Pooled ORs were not affected by patient age, drug class, depression subtype or treatment duration, and were similar when calculated by different statistical methods. Patients with primary depression diagnosed by earlier diagnostic systems had slightly lower ORs than those diagnosed using DSM criteria.

CONCLUSIONS

This meta-analysis emphasizes the importance of continuation treatment following acute response in depressive disorders. The robust findings of relapse prevention designs contrast with acute antidepressant efficacy studies, and may be due to enrichment of the patient population.

Desvenlafaxine in major depressive disorder: an evidence-based review of its place in therapy

INTRODUCTION

Desvenlafaxine, the active metabolite of venlafaxine, is a serotonin norepinephrine reuptake inhibitor (SNRI) recently approved for the treatment of major depressive disorder. It is one of only three medications in this class available in the United States.

AIMS

The objective of this article is to review the published evidence for the safety and efficacy of desvenlafaxine, and to compare it to other antidepressants to delineate its role in the treatment of depression.

EVIDENCE REVIEW

At the recommended dose of 50 mg per day the rate of response and remission was similar to other SNRIs, as was the adverse effect profile. The rate of discontinuation was no greater than placebo, and a discontinuation syndrome was not observed at this dose. Higher doses were not associated with greater efficacy, but they did lead to more side effects, and the use of a taper prior to discontinuation. The most common side effects reported were insomnia, somnolence, dizziness, and nausea. Some subjects experienced clinically significant blood pressure elevation.

PLACE IN THERAPY

Like duloxetine, desvenlafaxine inhibits the reuptake of both norepinephrine and serotonin at the starting dose. Dual reuptake inhibitors have been shown to have small but statistically significantly greater rates of response and remission compared to selective serotonin reuptake inhibitors, and they have also shown early promise in the treatment of neuropathic pain. Desvenlafaxine may prove to be a valuable treatment option by expanding the limited number of available dual reuptake inhibitors.

Sertraline versus other antidepressive agents for depression

BACKGROUND

The National Institute for Health and Clinical Excellence clinical practice guideline on the treatment of depressive disorder recommended that selective serotonin reuptake inhibitors should be the first-line option when drug therapy is indicated for a depressive episode. Preliminary evidence suggested that sertraline might be slightly superior in terms of effectiveness.

OBJECTIVES

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

SEARCH STRATEGY

MEDLINE (1966 to 2008), EMBASE (1974 to 2008), the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register and the Cochrane Central Register of Controlled Trials up to July 2008. No language restriction was applied. Reference lists of relevant papers and previous systematic reviews were hand-searched. Pharmaceutical companies and experts in this field were contacted for supplemental data.

SELECTION CRITERIA

Randomised controlled trials allocating patients with major depression to sertraline versus any other antidepressive agent.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data. Discrepancies were resolved with another member of the team. A double-entry procedure was employed by two reviewers. Information extracted included study characteristics, participant characteristics, intervention details and outcome measures in terms of efficacy (the number of patients who responded or remitted), acceptability (the number of patients who failed to complete the study) and tolerability (side-effects).

MAIN RESULTS

A total of 59 studies, mostly of low quality, were included in the review, involving multiple treatment comparisons between sertraline and other antidepressant agents. Evidence favouring sertraline over some other antidepressants for the acute phase treatment of major depression was found, either in terms of efficacy (fluoxetine) or acceptability/tolerability (amitriptyline, imipramine, paroxetine and mirtazapine). However, some differences favouring newer antidepressants in terms of efficacy (mirtazapine) and acceptability (bupropion) were also found. In terms of individual side effects, sertraline was generally associated with a higher rate of participants experiencing diarrhoea.

AUTHORS' CONCLUSIONS

This systematic review and meta-analysis highlighted a trend in favour of sertraline over other antidepressive agents both in terms of efficacy and acceptability, using 95% confidence intervals and a conservative approach, with a random effects analysis. However, the included studies did not report on all the outcomes that were pre-specified in the protocol of this review. Outcomes of clear relevance to patients and clinicians were not reported in any of the included studies.

Fluvoxamine versus other anti-depressive agents for depression

BACKGROUND

Fluvoxamine, one of the oldest selective serotonin reuptake inhibitors (SSRIs), is prescribed to patients with major depression in many countries. Several studies have previously reviewed the efficacy and tolerability of fluvoxamine for the treatment of major depression. However, these reviews are now outdated.

OBJECTIVES

Our objective is to evaluate the effectiveness, tolerability and side effect profile of fluvoxamine for major depression in comparison with other anti-depressive agents, including tricyclics (TCAs), heterocyclics, other SSRIs, SNRIs, other newer agents and other conventional psychotropic drugs.

SEARCH STRATEGY

We searched the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register. Trial databases and ongoing trial registers in North America, Europe, Japan and Australia, were handsearched for randomised controlled trials. We checked reference lists of the articles included in the review, previous systematic reviews and major textbooks of affective disorder for published reports and citations of unpublished research. The date of last search was 31 August 2008.

SELECTION CRITERIA

We included all randomised controlled trials, published in any language, that compared fluvoxamine with any other active antidepressants in the acute phase treatment of major depression.

DATA COLLECTION AND ANALYSIS

Two independent review authors inspected citations and abstracts, obtained papers, extracted data and assessed the risk of bias of included studies. We analysed dichotomous data using odds ratios (ORs) and continuous data using the standardised mean difference (SMD). A random effects model was used to combine studies.

MAIN RESULTS

A total of 54 randomised controlled trials (n = 5122) were included. No strong evidence was found to indicate that fluvoxamine was either superior or inferior to other antidepressants regarding response, remission and tolerability. However, differing side effect profiles were evident, especially with regard to gastrointestinal side effects of fluvoxamine when compared to other antidepressants. For example, fluvoxamine was generally associated with a higher incidence of vomiting/nausea (versus imipramine, OR 2.23, CI 1.59 to 3.14; versus clomipramine, OR 2.13, CI 1.06 to 4.27; versus amitriptyline, OR 2.86, CI 1.31 to 2.63).

AUTHORS' CONCLUSIONS

We found no strong evidence that fluvoxamine was either superior or inferior to any other antidepressants in terms of efficacy and tolerability in the acute phase treatment of depression. However, differing side effect profiles were evident. Based on these findings, we conclude that clinicians should focus on practical or clinically relevant considerations, including these differences in side effect profiles.

Research design considerations for confirmatory chronic pain clinical trials: IMMPACT recommendations

There has been an increase in the number of chronic pain clinical trials in which the treatments being evaluated did not differ significantly from placebo in the primary efficacy analyses despite previous research suggesting that efficacy could be expected. These findings could reflect a true lack of efficacy or methodological and other aspects of these trials that compromise the demonstration of efficacy. There is substantial variability among chronic pain clinical trials with respect to important research design considerations, and identifying and addressing any methodological weaknesses would enhance the likelihood of demonstrating the analgesic effects of new interventions. An IMMPACT consensus meeting was therefore convened to identify the critical research design considerations for confirmatory chronic pain trials and to make recommendations for their conduct. We present recommendations for the major components of confirmatory chronic pain clinical trials, including participant selection, trial phases and duration, treatment groups and dosing regimens, and types of trials. Increased attention to and research on the methodological aspects of confirmatory chronic pain clinical trials has the potential to enhance their assay sensitivity and ultimately provide more meaningful evaluations of treatments for chronic pain.

Pregabalin for painful HIV neuropathy: a randomized, double-blind, placebo-controlled trial

OBJECTIVE

Pregabalin is effective in several neuropathic pain syndromes. This trial evaluated its efficacy, safety, and tolerability for treatment of painful HIV-associated neuropathy.

METHODS

This randomized, double-blind, placebo-controlled, parallel-group trial included a 2-week double-blind dose-adjustment (150-600 mg/day BID) phase, a 12-week double-blind maintenance phase, and an optional 3-month open label extension phase. The primary efficacy measure was the mean Numeric Pain Rating Scale (NPRS) score, an 11-point numeric rating scale. Secondary measures included Patient Global Impression of Change (PGIC) and sleep measurements.

RESULTS

Baseline mean NPRS score was 6.93 for patients randomized to pregabalin (n = 151) and 6.72 for those to placebo (n = 151). Pregabalin average daily dosage (SD) was 385.7 (160.3) mg/d. At endpoint, pregabalin and placebo showed substantial reductions in mean NPRS score from baseline: -2.88 vs -2.63, p = 0.3941. Pregabalin had greater improvements in NPRS score relative to placebo at weeks 1 (-1.14 vs -0.69, p = 0.0131) and 2 (-1.92 vs -1.43, p = 0.0393), and at weeks 7 (-3.22 vs -2.53 p = 0.0307) and 8 (-3.33 vs -2.53, p = 0.0156). At all other time points, differences between groups were not significant. Sleep measurements and 7-item PGIC did not differ among treatment groups; however, collapsed PGIC scores showed 82.8% of pregabalin and 66.7% of placebo patients rated themselves in 1 of the 3 "improved" categories (p = 0.0077). Somnolence and dizziness were the most common adverse events with pregabalin.

CONCLUSIONS

Pregabalin was well-tolerated, but not superior to placebo in the treatment of painful HIV neuropathy. Factors predicting analgesic response in HIV neuropathy warrant additional research.

CLASSIFICATION OF EVIDENCE

This Class II trial showed that pregabalin is not more effective than placebo in treatment of painful HIV neuropathy.

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.

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.

Escitalopram versus other antidepressive agents for depression

BACKGROUND

Although pharmacological and psychological interventions are both effective for major depression, antidepressant drugs remain the mainstay of treatment in primary and secondary care settings. During the last 20 years, antidepressant prescribing has risen dramatically in western countries, mainly because of the increasing consumption of selective serotonin reuptake inhibitors (SSRIs) and newer antidepressants, which have progressively become the most commonly prescribed antidepressants. Escitalopram is the pure S-enantiomer of the racemic citalopram.

OBJECTIVES

To assess the evidence for the efficacy, acceptability and tolerability of escitalopram in comparison with tricyclics, other SSRIs, heterocyclics and newer agents in the acute-phase treatment of major depression.

SEARCH STRATEGY

Electronic databases were searched up to July 2008. Trial databases of drug-approving agencies were hand-searched for published, unpublished and ongoing controlled trials.

SELECTION CRITERIA

All randomised controlled trials comparing escitalopram against any other antidepressant (including non-conventional agents such as hypericum) for patients with major depressive disorder (regardless of the diagnostic criteria used).

DATA COLLECTION AND ANALYSIS

Data were entered by two review authors (double data entry). Responders and remitters to treatment were calculated on an intention-to-treat basis. For dichotomous data, odds ratios (ORs) were calculated with 95% confidence intervals (CI). Continuous data were analysed using standardised mean differences (with 95% CI) using the random effects model.

MAIN RESULTS

Fourteen trials compared escitalopram with another SSRI and eight compared escitalopram with a newer antidepressive agent (venlafaxine, bupropion and duloxetine). Escitalopram was shown to be significantly more effective than citalopram in achieving acute response (OR 0.67, 95% CI 0.50 to 0.87). Escitalopram was also more effective than citalopram in terms of remission (OR 0.53, 95% CI 0.30 to 0.93). Significantly fewer patients allocated to escitalopram withdrew from trials compared with patients allocated to duloxetine, for discontinuation due to any cause (OR 0.62, 95% CI 0.38 to 0.99).

AUTHORS' CONCLUSIONS

Some statistically significant differences favouring escitalopram over other antidepressive agents for the acute phase treatment of major depression were found, in terms of efficacy (citalopram and fluoxetine) and acceptability (duloxetine). There is insufficient evidence to detect a difference between escitalopram and other antidepressants in early response to treatment (after two weeks of treatment). Cost-effectiveness information is also needed in the field of antidepressant trials. Furthermore, as with most standard systematic reviews, the findings rely on evidence from direct comparisons. The potential for overestimation of treatment effect due to sponsorship bias should also be borne in mind.

Sertraline versus other antidepressive agents for depression

BACKGROUND

The National Institute for Health and Clinical Excellence clinical practice guideline on the treatment of depressive disorder recommended that selective serotonin reuptake inhibitors should be the first-line option when drug therapy is indicated for a depressive episode. Preliminary evidence suggested that sertraline might be slightly superior in terms of effectiveness.

OBJECTIVES

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

SEARCH STRATEGY

MEDLINE (1966 to 2008), EMBASE (1974 to 2008), the Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register and the Cochrane Central Register of Controlled Trials up to July 2008. No language restriction was applied. Reference lists of relevant papers and previous systematic reviews were hand-searched. Pharmaceutical companies and experts in this field were contacted for supplemental data.

SELECTION CRITERIA

Randomised controlled trials allocating patients with major depression to sertraline versus any other antidepressive agent.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data. Discrepancies were resolved with another member of the team. A double-entry procedure was employed by two reviewers. Information extracted included study characteristics, participant characteristics, intervention details and outcome measures in terms of efficacy (the number of patients who responded or remitted), acceptability (the number of patients who failed to complete the study) and tolerability (side-effects).

MAIN RESULTS

A total of 59 studies, mostly of low quality, were included in the review, involving multiple treatment comparisons between sertraline and other antidepressant agents. Evidence favouring sertraline over some other antidepressants for the acute phase treatment of major depression was found, either in terms of efficacy (fluoxetine) or acceptability/tolerability (amitriptyline, imipramine, paroxetine and mirtazapine). However, some differences favouring newer antidepressants in terms of efficacy (mirtazapine) and acceptability (bupropion) were also found. In terms of individual side effects, sertraline was generally associated with a higher rate of participants experiencing diarrhoea.

AUTHORS' CONCLUSIONS

This systematic review and meta-analysis highlighted a trend in favour of sertraline over other antidepressive agents both in terms of efficacy and acceptability, using 95% confidence intervals and a conservative approach, with a random effects analysis. However, the included studies did not report on all the outcomes that were pre-specified in the protocol of this review. Outcomes of clear relevance to patients and clinicians were not reported in any of the included studies.

An integrated analysis of the efficacy of desvenlafaxine compared with placebo in patients with major depressive disorder

INTRODUCTION

To assess the efficacy of desvenlafaxine (administered as desvenlafaxine succinate) in outpatients with major depressive disorder.

METHODS

A meta-analysis of individual patient data was performed on the complete set of registration trials (nine randomized, double-blind, placebo-controlled 8-week studies) of desvenlafaxine. Patients received fixed (50, 100, 200, or 400 mg/day; n=1,342) or flexible doses (100-400 mg/day; n=463) of desvenlafaxine or placebo (n=1,108). The primary efficacy variable was the 17-item Hamilton Rating Scale for Depression (HAM-D(17)); the primary intent to treat analyses used the last-observation-carried-forward method.

RESULTS

Significantly greater improvement with desvenlafaxine versus placebo on the HAM-D(17) total score was observed for the full data set (difference in adjusted means: -1.9; P<.001), each fixed-dose group (all P<.001), and the flexible-dose group (P=.024). Overall rates of HAM-D1(17) response (> or =150% decrease from baseline score: 53% vs 41%) and remission (HAM-D(17) < or =7: 32% vs 23%) were significantly greater for desvenlafaxine versus placebo (all P<.001). Discontinuation rates due to adverse events increased with dose (4% to 18%; placebo: 3%).

CONCLUSION

Desvenlafaxine demonstrated short-term efficacy for treating major depressive disorder across the range of doses studied. No evidence of greater efficacy was observed with doses >50 mg/day; a strong dose-response effect on tolerability was observed.

Does the probability of receiving placebo influence clinical trial outcome? A meta-regression of double-blind, randomized clinical trials in MDD

Substantial and highly variable placebo response rates represent a major obstacle to antidepressant development in major depressive disorder (MDD). However, whether the likelihood of receiving active treatment or placebo, a proxy of the degree of expectation of improvement, may itself influence clinical trial outcome is unclear. The goal of this work was to examine whether the probability of receiving placebo influences clinical trial outcome antidepressant MDD trials. Medline/Pubmed publication databases were searched for randomized, double-blind, placebo-controlled trials of antidepressants for adults with MDD. 146 manuscripts involving 182 clinical trials were pooled (n = 36,385). Pooled response rates for drug and placebo were 53.8% and 37.3%. A meta-regression (random-effects) established that the probability of receiving placebo, year of publication, and baseline severity were independent predictors of the risk ratio of responding to antidepressants versus placebo. Specifically, a greater probability of receiving placebo, greater baseline severity and an earlier year of publication predicted greater antidepressant-placebo "efficacy separation". Fixed versus flexible dose design, trial duration and population age did not influence clinical trial outcome.

Daily left prefrontal repetitive transcranial magnetic stimulation in the acute treatment of major depression: clinical predictors of outcome in a multisite, randomized controlled clinical trial

Randomized controlled trials support the antidepressant efficacy of transcranial magnetic stimulation (TMS); however, there is individual variability in the magnitude of response. Examination of response predictors has been hampered by methodological limitations such as small sample sizes and single-site study designs. Data from a multisite sham-controlled trial of the antidepressant efficacy of TMS provided an opportunity to examine predictors of acute outcome. An open-label extension for patients who failed to improve provided the opportunity for confirmatory analysis. Treatment was administered to the left dorsolateral prefrontal cortex at 10 pulses per second, 120% of motor threshold, for a total of 3000 pulses per day. Change on the Montgomery-Asberg Depression Rating Scale after 4 weeks was the primary efficacy outcome. A total of 301 patients with nonpsychotic unipolar major depression at 23 centers were randomized to active or sham TMS. Univariate predictor analyses showed that the degree of prior treatment resistance in the current episode was a predictor of positive treatment outcome in both the controlled study and the open-label extension trial. In the randomized trial, shorter duration of current episode was also associated with a better outcome. In the open-label extension study, absence of anxiety disorder comorbidity was associated with an improved outcome, but duration of current episode was not. The number of prior treatment failures was the strongest predictor for positive response to acute treatment with TMS. Shorter duration of current illness and lack of anxiety comorbidity may also confer an increased likelihood of good antidepressant response to TMS.

A pilot effectiveness study: placebo-controlled trial of adjunctive L-triiodothyronine (T3) used to accelerate and potentiate the antidepressant response

The aim was to evaluate whether adjunctive T3 can help accelerate the antidepressant response and improve overall outcomes when used under naturalistic conditions. Fifty consecutive psychiatric outpatients diagnosed with major depressive disorder who were initiated on antidepressant therapy were randomized to receive adjunctive T3 or placebo in a double-blind manner over the course of 6 wk. There were no restrictions placed on the selection of antidepressant agent, dosing, ancillary medications, or psychotherapy, and there were few exclusion criteria. A positive response was defined as a > or = 50% reduction in Montgomery-Asberg Depression Rating Scale scores. Response rates were higher for the adjunctive T3 cohort compared to the adjunctive placebo cohort after 1 wk (45% vs. 24%) and 2 wk (57% vs. 33%) of treatment. The likelihood of experiencing a positive response at any point over the 6-wk trial was 4.5 times greater in the adjunctive T3 cohort (95% CI 1.3-15.7). The study provides preliminary evidence that T3 can successfully be used in clinical practice to accelerate the antidepressant response and improve overall outcomes. The effectiveness model may be an untapped mechanism for evaluating the value of psychopharmacological agents.

Efficacy of duloxetine and selective serotonin reuptake inhibitors: comparisons as assessed by remission rates in patients with major depressive disorder

It has been proposed that serotonin and norepinephrine reuptake inhibitors (SNRIs) may result in higher remission rates of major depressive disorder than therapy with selective serotonin reuptake inhibitors (SSRIs). To test this hypothesis, a meta-analysis of individual patient data (N = 1833) was performed for the complete set of 6 phase II/III studies that compared duloxetine (fixed doses; range, 40-120 mg/d) with 2 SSRIs (paroxetine or fluoxetine; 20 mg/d) in outpatients with major depressive disorder. Remission was defined as an end point score of less than or equal to 7 on the 17-item Hamilton Rating Scale for Depression (HAMD17); alternate outcome criteria were also examined, as were remission rates among the 1044 patients with moderate-to-severe depression (HAMD17 total score greater than or equal to 19). The HAMD17 remission rates were 40.3% (351/871), 38.3% (162/423), and 28.4% (144/507) for duloxetine, the 2 SSRIs, and placebo, respectively. Both active treatments were superior to placebo; the difference between duloxetine and SSRIs was not statistically significant. Similar findings were observed for alternate outcomes. Duloxetine therapy was significantly more effective than therapy with the 2 SSRIs for patients with more severe depression, with remission rates of 35.9% (183/510) versus 28.6% (70/245) (P = 0.046). A secondary analysis of dose-response relationships indicated that this advantage was not attributable to the studies using higher doses of duloxetine. Thus, whereas duloxetine and the 2 SSRIs were comparably efficacious overall, therapy with the serotonin and norepinephrine reuptake inhibitor resulted in a significantly higher remission rate among patients with moderate-to-severe depression.

An effect-size analysis of pharmacologic treatments for generalized anxiety disorder

Generalized anxiety disorder (GAD) is a prevalent and impairing disorder, associated with extensive psychiatric and medical comorbidity and usually characterized by a chronic course. Different drugs have been investigated in GAD; among them are the following: 1) SSRIs: paroxetine, sertraline, fluvoxamine and escitalopram; 2) SNRI1s: venlafaxine; 3) benzodiazepines (BZs): alprazolam, diazepam and lorazepam; 4) azapirones (AZAs): buspirone; 5) antihistamines (AHs): hydroxyzine; 6) pregabalin (PGB); and 7) complementary/alternative medicine (CAM): kava-kava and homeopathic preparation. We conducted an effect size (ES) analysis of 21 double-blind placebo-controlled trials of medications treating DSM-III-R, DSM-IV or ICD-10 GAD using HAM-A change in score from baseline or endpoint score as the main efficacy measure. Literature search was performed using MEDLINE and PsycINFO databases including articles published between 1987 and 2003 and personal communications with investigators and sponsors. comparing all drugs versus placebo, the ES was 0.39. Mean ESs, excluding children, were PGB: 0.50, AH: 0.45, SNRI: 0.42, BZ: 0.38, SSRI: 0.36, AZA: 0.17 and CAM: -0.31. Comparing ES for adults versus children/adolescents (excluding CAM) and conventional drugs versus CAM (excluding children/adolescents) we found significantly higher ES for children/adolescents and for conventional drugs (p < 0.001 and p < 0.01, respectively). No significant differences were found when comparing date of publication, location of site (i.e. US versus other), fixed versus flexible dosing, number of study arms, or number of outcome measures used. Medications varied in the magnitude of their ES, ranging from moderate to poor. Adolescents and children showed a much greater ES compared with adults. Subjects taking CAM had worse outcomes than placebo.

Psychiatric diagnosis and clinical trial completion rates: analysis of the FDA SBA reports

Completion rates may affect the safety and efficacy evaluations of psychotropics. We assessed completion rates in clinical trials evaluating psychotropics for five psychiatric disorders. We also examined differences in completion rates between psychotropics and placebo in each diagnostic category. We reviewed clinical data in the Food and Drug Administration summary basis of approval reports for 20 psychotropics evaluated for the treatment of depression, schizophrenia, obsessive compulsive disorder (OCD), generalized anxiety disorder (GAD), or panic disorder, consisting of 19 710 patients. Patients with OCD had the highest completion rates (78.0%), followed by patients with panic disorder (74.4%), GAD (69.2%), depression (64.7%) and schizophrenia (49.0%). Patients assigned to placebo had significantly lower completion rates in antipsychotic clinical trials. Patients assigned to psychotropics in OCD trials had significantly lower completion rates compared to the placebo group. A greater number of early terminations relating to a lack of efficacy was seen among patients assigned to placebo (17.4%) compared with patients assigned to psychotropics (12.2%). A greater number of early terminations relating to adverse events was seen among patients assigned to psychotropics (10.4%) compared with patients assigned to placebo (4.8%). Our findings suggest that psychiatric diagnosis and treatment assignment (placebo vs psychotropic) were associated with completion rates in clinical trials. These findings may help in the design of future psychopharmacology clinical trials.

Efficacy of agomelatine, a MT1/MT2 receptor agonist with 5-HT2C antagonistic properties, in major depressive disorder

Current antidepressants used in major depressive disorder (MDD) are still not efficacious enough for many patients due to high levels of treatment resistance and bothersome side-effects. Using a novel blinding method (interactive voice response system), this flexible-dosing study examined the effects of therapeutic doses of agomelatine, a new approach to depressive therapy offering potent melatonergic MT1/MT2 receptor agonism with 5-HT2C receptor antagonist properties, in patients with moderate-to-severe MDD. This 6-wk, double-blind, parallel-group study randomized 238 patients to 25 mg/d agomelatine (with dose adjustment at 2 wk to 50 mg/d in patients with insufficient improvement) or placebo. Depression severity was assessed using the Hamilton Depression Rating Scale (HAMD) and the Clinical Global Impression (CGI) scale. Agomelatine was significantly more efficacious than placebo, with an agomelatine-placebo difference of 3.44 (p<0.001) using the HAMD final total score. Compared with placebo, agomelatine also had a significant positive impact on CGI - Improvement (treatment difference=0.45) and CGI - Severity (treatment difference=0.50) (both p=0.006), response rate (54.3% vs. 35.5% with placebo, p<0.05) and time to first response (p=0.008). Similar results were seen in patients with the most severe MDD. Depressed mood and sleep items of the HAMD were also significantly improved with agomelatine, which was well tolerated with a safety profile similar to placebo at both doses. This study confirms that agomelatine is effective in treating major depression, including the most severely depressed patients, with a good safety and tolerability profile, therefore providing physicians with an effective pharmacological approach to antidepressant therapy.

Relationship between depression severity entry criteria and antidepressant clinical trial outcomes

BACKGROUND

We assessed whether increasing the minimum prerandomization Hamilton Depression Rating Scale (HAM-D) score to enrich the severity of the depressed sample affects antidepressant trial outcome.

METHODS

Using the Food and Drug Administration Summary Basis of Approval reports, we examined outcome data from 51 clinical trials (11,270 depressed patients) evaluating 10 investigational antidepressants.

RESULTS

Using four categories of trials with increasing minimum HAM-D entry trial criteria, we found no statistically significant relationship between prerandomization categories and trial outcome overall. Although there were minor differences in trial outcome among the three categories with the lowest entry criteria (mean 49%, range, 44.4%-50.0%), the antidepressant trials requiring the highest prerandomization HAM-D score (> or = 20 HAM-D 17) had the lowest frequency of positive outcomes (20%), chi(2) = 4.04, df =1, p = .04. Paradoxically, high entry criteria requirements failed to increase reliably actual mean total prerandomization HAM-D scores, although mean total prerandomization HAM-D scores and use of flexible dosing were associated with higher rates of positive outcome. A greater placebo response was seen in trials requiring higher prerandomization depressive symptoms.

CONCLUSIONS

In summary, requiring higher prerandomization depressive symptoms was not associated with an increased rate of favorable outcomes among these 51 antidepressant trials.

Use of effect size to determine optimal dose of duloxetine in major depressive disorder

OBJECTIVE

At effective doses, patients with major depressive disorder (MDD) treated with duloxetine have been found to experience significant symptom improvement as measured by HAMD(17) total score. In addition, duloxetine-treated patients have significantly higher remission and response rates compared with placebo. The objective of this analysis is to determine the optimal dose of duloxetine in MDD.

MATERIALS AND METHODS

Effect size for duloxetine 40mg, 60mg, 80mg, and 120mg per day were estimated using all 6 acute phase III clinical trials in patients with MDD. The tolerability of duloxetine 40mg, 60mg, 80mg, and 120mg were evaluated using pooled data from the 6 studies. The primary efficacy measure in all trials was the HAMD(17) total score, from which were determined the effect size for HAMD(17) change scores, response rates (50% reduction from baseline to endpoint), and remission rates (HAMD(17) total score < or =7).

RESULTS

A total of 1619 randomized patients were included in these studies, of which 632 were treated with placebo; 177 with duloxetine 40mg/day; 251 with 60mg/day; 363 with 80mg/day; and 196 with 120mg/day. An evaluation of increments in effect size between doses consistently showed that the most notable gain in effect size for efficacy was the 40-60mg/day dosage range. All dosages from 60 to 120mg were effective. The tolerability assessment indicated duloxetine at 40-120mg/day is well tolerated. Furthermore, the initial doses of 40-80mg/day were found to have comparable tolerability.

CONCLUSIONS

The effect size analyses demonstrate that duloxetine 40mg has minimum efficacy, and that duloxetine 60-120mg/day is effective in the treatment of patients with MDD. An initial dose less than 60mg/day might provide better tolerability for some patients diagnosed with MDD.

The convergence of conventional therapeutic drug monitoring and pharmacogenetic testing in personalized medicine: focus on antidepressants

The development and prospects of conventional therapeutic drug monitoring (TDM) and pharmacogenetic testing as aids in personalized treatment with antidepressants and antipsychotics are described. Our own experience is discussed in relation to international guidelines for rational TDM. Emphasis is put on the usefulness of TDM combined with genotyping of cytochrome P450 2D6 (CYP2D6), the key enzyme involved in the polymorphic metabolism of the majority of antidepressants (both tricyclics and selective serotonin reuptake inhibitors) and antipsychotic drugs. This combination of methods is particularly useful in verifying concentration-dependent adverse drug reactions (ADRs) due to poor metabolism, 'and diagnosing pharmacokinetic reasons (ultrarapid metabolism (UM)) for drug failure. This is because ADRs may mimic the psychiatric illness itself and therapeutic failure due to UM may be mistaken for poor compliance with the prescription.

Duloxetine versus escitalopram and placebo in the treatment of patients with major depressive disorder: onset of antidepressant action, a non-inferiority study

OBJECTIVE

The goal of a non-inferiority study is to test whether a new treatment has at least as much efficacy as an established treatment. The purpose of this non-inferiority study was to compare the speed of onset of antidepressant efficacy for duloxetine (a dual serotonin and norepinephrine reuptake inhibitor) and escitalopram (a selective serotonin reuptake inhibitor).

RESEARCH DESIGN AND METHODS

This was a randomized, double-blind, placebo- and active comparator-controlled study, in which patients (> or = 18 years) meeting DSM-IV criteria for Major Depressive Disorder (MDD) received duloxetine 60 mg once daily (QD; N = 273), escitalopram 10 mg QD (N = 274), or placebo (N = 137) for 8 weeks. The primary objective was to compare the onset of antidepressant efficacy, by testing the hypothesis that the percentage of duloxetine-treated patients achieving onset criteria at Week 2 was not inferior to that in the escitalopram group.

MAIN OUTCOME MEASURES

Onset of efficacy was defined as a 20% decrease from baseline on the 17-item Hamilton Rating Scale for Depression (HAMD(17)) Maier subscale that was maintained or exceeded at all subsequent visits.

RESULTS

Probabilities of meeting onset criteria at Week 2 for duloxetine- and escitalopram-treated patients were 42.6% versus 35.2%, respectively (treatment difference = 7.4%; 95% confidence interval, -1.3% to 16.2%; p = 0.097). Both drugs showed significant improvement compared with placebo (p < or = 0.05) on the primary efficacy measure (Maier subscale) at Week 1 and endpoint (Week 8). No differences were found between duloxetine, escitalopram, and placebo rates of remission or response at 8 weeks. Adverse events that occurred significantly more frequently among duloxetine-treated patients when compared with those receiving escitalopram were nausea, dry mouth, vomiting, yawning, and irritability. The rate of discontinuation due to adverse events did not differ significantly between treatment groups.

LIMITATIONS

Given the difficulties in constructing appropriate dose comparisons, the results of this study should be interpreted specific to the doses tested and not extrapolated to the drug as a whole. This study employed a fixed-dose design; flexible-dose designs are more likely to find a difference between antidepressants and placebo.

CONCLUSION

In this study, both duloxetine and escitalopram showed significantly greater improvement on the primary efficacy measure than placebo over the 8-week acute treatment period, while no differences were observed between drugs or between drugs and placebo on response and remission rates at 8 weeks. Escitalopram at a starting dose of 10 mg QD was better tolerated than duloxetine at a starting dose of 60 mg QD. This study met its pre-defined primary objective of assessing if duloxetine was non-inferior to escitalopram in antidepressant onset efficacy, and the results show that duloxetine is at least as fast as (non-inferior to) escitalopram.

An evidence-based approach to the management of depression

Increasing numbers of patients are using complementary medicine for the treatment of depression, which complicates management. What is the evidence in support of one medication over another? What medications are safe to use in children and pregnant women? Is there any evidence supporting over-the-counter supplements? These are just a few of the questions that primary care physicians face on a daily basis. This article attempts to answer these questions and many others in an evidence-based approach to the management of depression, which focuses on diagnosis, medical management, and complementary treatments.

Venlafaxine versus other anti-depressive agents for depression

This is the protocol for a review and there is no abstract. The objectives are as follows: To determine the efficacy of venlafaxine in comparison with other anti-depressive agents in alleviating the acute symptoms of major depressive disorder.To review acceptability of treatment with venlafaxine in comparison with other anti-depressive agents.To investigate the adverse effects of venlafaxine in comparison with other anti-depressive agents.

Paroxetine versus other anti-depressive agents for depression

This is the protocol for a review and there is no abstract. The objectives are as follows: To determine the efficacy of paroxetine in comparison with other anti-depressive agents in alleviating the acute symptoms of major depressive disorder.To review acceptability of treatment with paroxetine in comparison with other anti-depressive agents.To investigate the adverse effects of paroxetine in comparison with other anti-depressive agents.

Pregabalin for the treatment of generalised anxiety disorder

Pregabalin is a new anxiolytic that has been recently licensed for the treatment of generalised anxiety disorder (GAD) in Europe. Short-term efficacy is based on six positive placebo-controlled studies, all of which showed a significant early separation from placebo in all of the doses used (150-600 mg) at the first week, and the efficacy at the end of the treatment was comparable with the comparators used in four of these studies. Pregabalin was effective in more or less severe GAD, on psychic and somatic symptoms of GAD, and in treating the subsyndromal depressive symptoms of GAD. Efficacy in the elderly was shown in a separate placebo-controlled study. The effect on cognitive function was minimal and notably less than that observed with benzodiazepines. The discontinuation symptoms following abrupt treatment cessation were similar to the rates with serotonin-noradrenaline re-uptake inhibitors and lower than with benzodiazepines with no signals of tolerance or dependence.

The circadian basis of winter depression

The following test of the circadian phase-shift hypothesis for patients with winter depression (seasonal affective disorder, or SAD) uses low-dose melatonin administration in the morning or afternoon/evening to induce phase delays or phase advances, respectively, without causing sleepiness. Correlations between depression ratings and circadian phase revealed a therapeutic window for optimal alignment of circadian rhythms that also appears to be useful for phase-typing SAD patients for the purpose of administering treatment at the correct time. These analyses also provide estimates of the circadian component of SAD that may apply to the antidepressant mechanism of action of appropriately timed bright light exposure, the treatment of choice. SAD may be the first psychiatric disorder in which a physiological marker correlates with symptom severity before, and in the course of, treatment in the same patients. The findings support the phase-shift hypothesis for SAD, as well as suggest a way to assess the circadian component of other psychiatric, sleep, and chronobiologic disorders.