Efficacy of venlafaxine in major depression resistant to selective serotonin reuptake inhibitors

The selective norepinephrine reuptake inhibitor reboxetine promotes late-stage fracture healing in mice

Impaired fracture healing is of high clinical relevance, as up to 15% of patients with long-bone fractures display non-unions. Fracture patients also include individuals treated with selective norepinephrine reuptake inhibitors (SNRI). As SNRI were previously shown to negatively affect bone homeostasis, it remained unclear whether patients with SNRI are at risk of impaired bone healing. Here, we show that daily treatment with the SNRI reboxetine reduces trabecular bone mass in the spine but increases cortical thickness and osteoblast numbers in the femoral midshaft. Most importantly, reboxetine does not impair bone regeneration in a standardized murine fracture model, and even improves callus bridging and biomechanical stability at late healing stages. In sum, reboxetine affects bone remodeling in a site-specific manner. Treatment does not interfere with the early and intermediate stages of bone regeneration and improves healing outcomes of the late-stage fracture callus in mice.

Venlafaxine and O-desmethylvenlafaxine serum levels are positively associated with antidepressant response in elder depressed out-patients

BACKGROUND

Therapeutic Drug Monitoring (TDM) represents one of the most promising tools in clinical practice to optimise antidepressant treatment. Nevertheless, little is still known regarding the relationship between clinical efficacy and serum concentration of venlafaxine (VEN). The aim of our study was to investigate the association between serum concentration of venlafaxine + O-desmethylvenlafaxine (SCVO) and antidepressant response (AR).

METHODS

52 depressed outpatients treated with VEN were recruited and followed in a naturalistic setting for three months. Hamilton Depression Rating Scale-21 was administered at baseline, at month 1 and at month 3 to assess AR. SCVO was measured at steady state. Linear regression analysis and nonlinear least-squares regression were used to estimate association between SCVO and AR.

RESULTS

Our results showed an association between AR and SCVO that follows a bell-shaped quadratic function with a progressive increase of AR within the therapeutic reference range of SCVO (i.e. 100-400 ng/mL) and a subsequent decrease of AR at higher serum levels.

DISCUSSION

This study strongly suggests that TDM could represent a more appropriate tool than the oral dosage to optimise the treatment with VEN. Specifically, highest efficacy might be achieved by titrating patients at SCVO levels around 400 ng/mL.

Does the Presence of Dissociative Symptoms Affect the Response to Venlafaxine Treatment for Major Depression? An Open-Label, Prospective Study

Many psychiatric diseases may be accompanied by dissociative symptoms and disorders. This study examined whether dissociative symptoms affect the response to venlafaxine treatment for major depressive disorder (MDD). The study included 40 patients who had a diagnosis of MDD according toDiagnostic and Statistical Manual of Mental Disorders(fifth edition) criteria. Venlafaxine was administered to each patient (37.5 mg to 150 mg daily) for 10 weeks. The researchers used the Beck Depression Inventory (BDI) and the Dissociation Questionnaire (DIS-Q) on cases with MDD at the beginning of the study. The researchers divided the patients into two groups according to DIS-Q scores and conducted the BDI again at the end of the 10-week period.

The authors detected the difference between the values of decrease in BDI scores as a percentage. They found these values to be 48.03% ± 29.03 in the low DIS-Q group and 27.06% ± 32.91 in the high DIS-Q group. They also found a significant difference between the groups (z = −2.167; P = .030). This study showed that, in patients with MDD, intense dissociative experiences reduced the response to venlafaxine therapy.

[Psychiatr Ann2022;52(3):119–125.]

Pharmacokinetic-Pharmacodynamic interaction associated with venlafaxine-XR remission in patients with major depressive disorder with history of citalopram / escitalopram treatment failure

BACKGROUND

The purpose of this study was to identify specific pharmacokinetic (PK) and pharmacodynamics (PD) factors that affect the likelihood of treatment remission with a serotonin norepinephrine reuptake inhibitor (SNRI) in depressed patients whose initial selective serotonin reuptake inhibitor (SSRI) failed.

METHODS

Multiple logistic regression modeling of PK and PD variation hypothesized to contribute to SNRI (i.e. duloxetine or venlafaxine) treatment remission in prior SSRI (i.e. citalopram or escitalopram) failure was conducted on 139 subjects from the Pharmacogenomics Research Network (PGRN) and Sequenced Treatment Alternatives to Relieve Depression (STAR*D) studies. Depressive symptoms were assessed with the Quick Inventory of Depressive Symptomatology Clinician-rated (QIDS-C₁₆).

RESULTS

Venlafaxine-XR remission was associated with a significant interaction between CYP2D6 ultra-rapid metabolizer (URM) phenotype and SLC6A4 5-HTTLPR L/L genotype. A similar significant interaction effect was observed between CYP2D6 URM and SLC6A2 G1287A GA genotype. Stratifying by transporter genotypes, venlafaxine-XR remission was associated with CYP2D6 URM in patients with SLC6A4 L/L (p = 0.001) and SLC6A2 G1287A GA genotypes.

LIMITATIONS

The primary limitation of this post hoc study was small sample size.

CONCLUSION

Our results suggest that CYP2D6 ultra-rapid metabolizer status contributes to venlafaxine-XR treatment remission in MDD patients; in particular, there is a PK-PD interaction with treatment remission associated with CYP2D6 URM phenotype and SLC6A4 5-HTTLPR L/L or SLC6A2 G1287A G/A genotype, respectively. These preliminary data are encouraging and support larger pharmacogenomics studies differentiating treatment response to mechanistically different antidepressants in addition to further PK-PD interactive analyses.

Antidepressant medication use in palliative care

Depression and other mood disorders occur in approximately 25 percent of terminal patients. Untreated, depression and mood disorders can have a significantly negative impact on patients andfamilies. Screeningfor depression can be done as easily as asking one question: “Areyou depressed?” A positive response to this question can be followed with one of the more extensive screening tools. Anxiety disorders can also have a negative effect on patients and their families. These can be identified by also using one of the validated screening tools. Use of the antidepressant medications for treating depression and, in some cases, anxiety disorders has not been well studied in hospice and palliative care. Some of the antidepressants can also serve as adjuvant therapy in pain management.

What to expect from a third step in treatment resistant depression: A prospective open study on escitalopram

OBJECTIVES

Only few studies investigated treatment strategies for treatment resistant depression (TRD). The objective of this multicentre study was to evaluate TRD patients who did not respond to at least two antidepressants.

METHODS

A total of 417 patients, who failed to respond to a previous retrospectively assessed antidepressant (AD1), were firstly included in a 6-week venlafaxine treatment (AD2); secondly, those who failed to respond were treated for further 6 weeks with escitalopram (AD3).

RESULTS

Out of 417 patients who had failed to respond to previous treatment (AD1), 334 completed treatment with venlafaxine to prospectively define TRD. In the intent to treat (ITT) population in the first phase of the trial (AD2), responders to venlafaxine were 151 (36.21%) out of which remitters were 83 (19.90%). After phase one, 170 non-responders, defined as TRD, were included in the second phase and 157 completed the course. Of the 170 ITT entering the second phase (AD3), responders to escitalopram were 71 (41.76%) out of which remitters were 39 (22.94%). After the third treatment, patients showed a dropout rate of 7.65% and a rate of presence of at least one serious adverse event of 19.18%.

CONCLUSIONS

Relevant rates of response and remission may be observed after a third line treatment in patients resistant to two previous treatments. A relevant limitation of this study was represented by the design: naturalistic, non-randomized, open-label, without a control sample and with unblinded raters.

Double-Blind Randomized Clinical Trial of the Efficacy of Venlafaxine Versus Citalopram in the Treatment of the Acute Phase of Major Depressive Disorder

Background:

There are many antidepressant medications with different side-effects and efficacy profiles.

Objectives:

In this study, we compared the efficacy of citalopram and venlafaxine in major depression, which has not yet been studied in Iran.

Patients and Methods:

In this double-blind, randomized controlled trial study, 39 patients aged 18-54 year old with major depressive disorder were randomly allocated into two groups in Yazd City, Iran, between March 2011 and December 2012. A total of 16 patients were treated with velafaxine and 23 patients were treated with citalopram for 8 weeks. Hamilton Depression Rating Scale (HDRS) questionnaire was used for monitoring depression severity. Data were analyzed by SPSS version 20.0 software using Mann Whitney U test and chi-square statistical tests.

Results:

The HDRS scores were decreased significantly in each group after 8 weeks of treatment (P = 0.001). However, there was no significant difference considering the score of HDRS (P = 0.110). Ten patients in the venlafaxine group and two patients in the citalopram group stopped using medication, all due to nausea or vomiting, or both, and the rate of these two side-effects was significantly higher in the venlafaxine group (P = 0.010).

Conclusions:

The efficacy of venlafaxine and citalopram are almost the same, but compliance for the use of medication, such as nausea and vomiting, in patients using venlafaxine is much higher than the citalopram group. Therefore, this implies that citalopram could be a safer antidepressant for patients suffering from major depression.

Targeting Treatment-Resistant Depression

Only 50% of depressed patients achieve remission of symptoms after 2 trials of antidepressants. Therefore one half of patients are considered treatment resistant. Studies have shown that with each failed antidepressant, chances of remission continue to decline. Untreated depressive symptoms lead to impaired social and occupational function, decline of physical health, suicidal thoughts, and increased health care utilization. Clinicians recognize there is an urgent need to find an efficacious treatment, but it becomes more difficult to decide on an appropriate therapy once a patient has failed 2 to 3 trials of antidepressants. An evidence-based review was performed to assess the efficacy and safety of several different antidepressant strategies to help the clinician decide which may be beneficial for specific patients.

Therapeutic options for treatment-resistant depression

Treatment-resistant depression (TRD) presents major challenges for both patients and clinicians. There is no universally accepted definition of TRD, but results from the US National Institute of Mental Health's (NIMH) STAR*D (Sequenced Treatment Alternatives to Relieve Depression) programme indicate that after the failure of two treatment trials, the chances of remission decrease significantly. Several pharmacological and nonpharmacological treatments for TRD may be considered when optimized (adequate dose and duration) therapy has not produced a successful outcome and a patient is classified as resistant to treatment. Nonpharmacological strategies include psychotherapy (often in conjunction with pharmacotherapy), electroconvulsive therapy and vagus nerve stimulation. The US FDA recently approved vagus nerve stimulation as adjunctive therapy (after four prior treatment failures); however, its benefits are seen only after prolonged (up to 1 year) use. Other nonpharmacological options, such as repetitive transcranial stimulation, deep brain stimulation or psychosurgery, remain experimental and are not widely available. Pharmacological treatments of TRD can be grouped in two main categories: 'switching' or 'combining'. In the first, treatment is switched within and between classes of compounds. The benefits of switching include avoidance of polypharmacy, a narrower range of treatment-emergent adverse events and lower costs. An inherent disadvantage of any switching strategy is that partial treatment responses resulting from the initial treatment might be lost by its discontinuation in favour of another medication trial. Monotherapy switches have also been shown to have limited effectiveness in achieving remission. The advantage of combination strategies is the potential to build upon achieved improvements; they are generally recommended if partial response was achieved with the current treatment trial. Various non-antidepressant augmenting agents, such as lithium and thyroid hormones, are well studied, although not commonly used. There is also evidence of efficacy and increasing use of atypical antipsychotics in combination with antidepressants, for example, olanzapine in combination with fluoxetine (OFC) or augmentation with aripiprazole. The disadvantages of a combination strategy include multiple medications, a broader range of treatment-emergent adverse events and higher costs. Several experimental pharmaceutical treatment alternatives for TRD are also being explored in combination with antidepressants or as monotherapy. These less studied alternative compounds include pindolol, inositol, CNS stimulants, hormones, herbal supplements, omega-3 fatty acids, S-adenosyl-L-methionine, folic acid, lamotrigine, modafinil, riluzole and topiramate. In summary, despite an increasing variety of choices for the treatment of TRD, this condition remains universally undefined and represents an area of unmet medical need. There are few known approved pharmacological agents for TRD (aripiprazole and OFC) and overall outcomes remain poor. This might be an indication that depression itself is a heterogeneous condition with a great diversity of pathologies, highlighting the need for careful evaluation of individuals with depressive symptoms who are unresponsive to treatment. Clearly, more research is needed to provide clinicians with better guidance in making those treatment decisions--especially in light of accumulating evidence that the longer patients are unsuccessfully treated, the worse their long-term prognosis tends to be.

Introduction: selecting an antidepressant

Four years ago, my colleagues and I published an article titled “Why isn't bupropion the most frequently prescribed antidepressant?” The goal of that article was not to advocate bupropion as the preferred agent for treating depression, but rather to stimulate discussion about how psychiatrists choose an antidepressant as well as to highlight the gap between results of efficacy studies and clinical decision making in real-world practice.

The argument in support of bupropion being the preferred antidepressant was based on three premises: all antidepressants are equally effective; adverse effects (AEs) of greatest concern to patients who take antidepressants are weight gain and sexual dysfunction; and bupropion does not cause either of these AEs. Acceptance of these three premises suggested the title of that article.

Although many reviews of the antidepressant literature, including the revised American Psychiatric Association Practice Guideline for the Treatment of Major Depressive Disorder, conclude that antidepressants are equally effective in general, several experts in the treatment of depression have suggested that medications with >1 mechanism of action may be more effective than agents that have more selective neurotransmitter effects. In a meta-analysis of eight studies comparing the remission rates in patients treated with the serotonin-norepinephrine reuptake inhibitor (SNRI) venlafaxine or selective serotonin reuptake inhibitors (SSRIs), Thase and colleagues demonstrated that venlafaxine was more effective than SSRIs in achieving remission in depressed patients. However, these conclusions were tentative as most of the included studies were comparisons of venlafaxine and fluoxetine; only one study included sertraline, and there were no studies of citalopram included in the review. In addition, patients who had previously failed treatment with an SSRI were not excluded, and, although patients who fail with one SSRI may respond to subsequent treatment with another SSRI, the inclusion of SSRI failures may favor venlafaxine in comparisons with SSRIs. Lastly, all of the studies included in the meta-analysis were funded by the manufacturer of venlafaxine.

The STAR*D Project results: a comprehensive review of findings

The Sequenced Treatment Alternatives to Relieve Depression trial enrolled outpatients with nonpsychotic major depressive disorder treated prospectively in a series of randomized controlled trials. These were conducted in representative primary and psychiatric practices. Remission rates for treatment steps 1 to 4 based on the 16-item Quick Inventory of Depressive Symptomatology-Self-report were 37%, 31%, 14%, and 13%, respectively. There were no differences in remission rates or times to remission among medication switch or among medication augmentation strategies at any treatment level. Participants who required increasing numbers of treatment steps showed greater depressive illness burden and increasingly greater relapse rates in the naturalistic follow-up period (40%-71%). Prognosis was better at all levels for participants who entered follow-up in remission as opposed to those who entered with response without remission. These results highlight the prevalence of treatment-resistant depression and suggest potential benefit for using more vigorous treatments in the earlier steps.

A Critical Overview of the Pharmacologic Management of Treatment-Resistant Depression

Major depressive disorder is a frequent, serious disorder that usually responds partially to treatment and leaves many patients with treatment resistance. This article reviews and critically evaluates the evidence for the management of treatment-resistant depression and examines pharmacologic approaches to alleviate the suffering of patients who benefit insufficiently from initial treatment.

A comparison of the efficacy and tolerability of reboxetine and sertraline versus venlafaxine in major depressive disorder: a randomized, open-labeled clinical trial

The aim of the study was to compare the efficacy and tolerability of the combination of reboxetine and sertraline to venlafaxine XR (extended release) in major depressive disorder (MDD). The study consisted of 40 patients with MDD, aged 18-65 years. Patients were evaluated six times during a 10-week period. Treatment was started as venlafaxine XR 75 mg/day once a day (od) or reboxetine 4 mg/day twice a day (bid)+sertraline 50 mg/day od. In the second week, venlafaxine XR was increased to 150 mg/day od and reboxetine 8 mg/day bid while sertraline was kept at the same dose. The Hamilton Depression Rating Scale (HDRS), Montgomery and Asberg Depression Rating Scale, Clinical Global Impressions-Severity of Illness and Clinical Global Impressions-Global Improvement Scale were applied on each visit. Beginning from the second visit, both groups showed significant declines in each scale. There were no significant differences between treatment response rates. Remission rates defined as HDRS<or=10 were significantly higher in the venlafaxine XR group at visit 4 only. However, when remission was accepted as HDRS<or=7, no significant difference was observed. Side effect frequency was similar between the treatment groups. We may suggest that the reboxetine+sertraline combination is not superior to venlafaxine treatment.

Bupropion-SR, sertraline, or venlafaxine-XR after failure of SSRIs for depression

BACKGROUND

After unsuccessful treatment for depression with a selective serotonin-reuptake inhibitor (SSRI), it is not known whether switching to one antidepressant is more effective than switching to another.

METHODS

We randomly assigned 727 adult outpatients with a nonpsychotic major depressive disorder who had no remission of symptoms or could not tolerate the SSRI citalopram to receive one of the following drugs for up to 14 weeks: sustained-release bupropion (239 patients) at a maximal daily dose of 400 mg, sertraline (238 patients) at a maximal daily dose of 200 mg, or extended-release venlafaxine (250 patients) at a maximal daily dose of 375 mg. The study was conducted in 18 primary and 23 psychiatric care settings. The primary outcome was symptom remission, defined by a total score of 7 or less on the 17-item Hamilton Rating Scale for Depression (HRSD-17) at the end of the study. Scores on the Quick Inventory of Depressive Symptomatology - Self Report (QIDS-SR-16), obtained at treatment visits, determined secondary outcomes, including remission (a score of 5 or less at exit) and response (a reduction of 50 percent or more on baseline scores).

RESULTS

Remission rates as assessed by the HRSD-17 and the QIDS-SR-16, respectively, were 21.3 percent and 25.5 percent for sustained-release bupropion, 17.6 percent and 26.6 percent for sertraline, and 24.8 percent and 25.0 percent for extended-release venlafaxine. QIDS-SR-16 response rates were 26.1 percent for sustained-release bupropion, 26.7 percent for sertraline, and 28.2 percent for extended-release venlafaxine. These treatments did not differ significantly with respect to outcomes, tolerability, or adverse events.

CONCLUSIONS

After unsuccessful treatment with an SSRI, approximately one in four patients had a remission of symptoms after switching to another antidepressant. Any one of the medications in the study provided a reasonable second-step choice for patients with depression. (ClinicalTrials.gov number, NCT00021528.).

An open-label study of duloxetine for the treatment of major depressive disorder: comparison of switching versus initiating treatment approaches

This study compared the stabilized duloxetine dose through approximately 12 weeks of treatment in patients initiating duloxetine therapy with that in patients switching to duloxetine from selective serotonin reuptake inhibitors or venlafaxine. All patients met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria for major depressive disorder. Patients (n = 112) exhibiting suboptimal response or poor tolerability to their current antidepressant medication (citalopram, escitalopram, fluvoxamine, paroxetine, sertraline, or venlafaxine) were switched to duloxetine 60 mg once daily (QD) without intermediate tapering or titration ("switching" group). A comparator group (n = 137), comprising patients not currently receiving antidepressant medication, was randomized to receive duloxetine 30 or 60 mg QD ("initiating" group). At the end of week 1, patients receiving 30 mg QD had their dose increased to 60 mg QD. During the remainder of the study, each patient's duloxetine dose could be titrated on the basis of degree of response within a range from 60 to 120 mg QD, with 90 mg QD as an intermediate dose. At the study end point, approximately one third of the patients in each treatment group were stabilized at each of the 3 studied duloxetine doses (60, 90, and 120 mg QD), and the distribution of stabilized doses among patients initiating duloxetine therapy did not differ significantly from that observed in patients switching to duloxetine. The efficacy of duloxetine in patients switching from selective serotonin reuptake inhibitor/venlafaxine did not differ significantly from that observed in untreated patients initiating duloxetine therapy (baseline-to-end point mean changes: 17-Item Hamilton Rating Scale for Depression total score, -13.1 vs. -13.5; Hamilton Rating Scale for Anxiety, -10.6 vs. -10.3; and Clinical Global Impression of Severity, -2.22 vs. -2.38, respectively). The rate of discontinuation caused by adverse events among patients switched to duloxetine was significantly lower than that in patients initiating duloxetine therapy (6.3% vs. 16.1%, P = 0.018). Treatment-emergent adverse events occurring in more than 10% of patients in both treatment groups were nausea, headache, dry mouth, insomnia, diarrhea, and constipation. In the first week of therapy, patients switched to duloxetine reported significantly lower rates of headache and fatigue compared with patients initiating duloxetine. Thus, the efficacy of duloxetine in switched patients was comparable to that observed in patients initiating duloxetine therapy. Immediate switching from a selective serotonin reuptake inhibitor or venlafaxine to duloxetine (60 mg QD) was well tolerated.

Preclinical pharmacology of F-98214-TA, a novel potent serotonin and norepinephrine uptake inhibitor with antidepressant and anxiolytic properties

RATIONALE

Serotonin (5-HT) and norepinephrine (NE) re-uptake inhibitors (SNRIs) have been proposed to have a higher efficacy and/or faster onset of action than previously available antidepressants.

OBJECTIVES

We examined in biochemical, electrophysiological and behavioural assays the antidepressant properties of (S)-(-)-4-[(3-fluorophenoxy)-phenyl]methyl-piperidine (F-98214-TA), a compound that displays very high affinity for 5-HT and NE transporters.

RESULTS

F-98214-TA potently inhibited the uptake of both 5-HT and NE into rat brain synaptosomes (IC50 = 1.9 and 11.2 nM, respectively) and decreased the electrical activity of dorsal raphe serotonergic neurones (ED50 = 530.3 microg/kg i.v.), an effect completely abolished by the 5-HT(1A) antagonist WAY100,635. In acute behavioural assays in mice, the orally administered compound potentiated the 5-hydroxy-tryptophan (5-HTP)-induced syndrome [minimal effective dose (MED) = 10 mg/kg], antagonized the hypothermia induced by a high dose of apomorphine (ED50 = 2 mg/kg) and reduced the immobility in the tail suspension test (MED = 10 mg/kg). Moreover, it also decreased the immobility in the forced swimming test in mice and rats (30 mg/kg, p.o.). Chronic administration of F-98214-TA (14 days, 30 mg kg(-1) day(-1), p.o.) attenuated the hyperactivity induced by olfactory bulbectomy in rats, confirming its antidepressant-like properties. Interestingly, the same dosage regimen significantly increased the social interaction time in rats, suggesting an additional potential anxiolytic activity. In most assays the compound was more potent than fluoxetine, venlafaxine and desipramine.

CONCLUSIONS

F-98214-TA is a novel SNRI that displays greater potency than other reference antidepressants in animal models predictive of antidepressant and anxiolytic activities.

Immediate switching of antidepressant therapy: results from a clinical trial of duloxetine

BACKGROUND

Approximately half of all treated depressed patients fail to show adequate response to their initially prescribed antidepressant medication. Switching to another medication represents one possible next-step approach for nonresponsive or partially responsive patients. However, specific techniques for switching between antidepressants have not been well studied. We examined the efficacy and tolerability associated with a switch from a selective serotonin reuptake inhibitor (SSRI) or venlafaxine to duloxetine.

METHODS

All patients met criteria for major depressive disorder as defined in DSM-IV. Patients (N = 88) exhibiting suboptimal response or poor tolerability to their current antidepressant medication (citalopram <or=40 mg/d, escitalopram <or=20 mg/d, fluvoxamine <or=150 mg/d, paroxetine <or=40 mg/d, sertraline <or=150 mg/d, or venlafaxine <or=150 mg/d) were switched to duloxetine 60 mg once-daily (QD) without intermediate tapering or titration ("switching" group). A comparator group (N = 67), comprising patients not currently receiving antidepressant medication, initiated duloxetine therapy at 60 mg QD ("initiating" group). Safety assessments included comparisons of discontinuation rates, treatment-emergent adverse events, and changes in vital signs. Efficacy measures included the HAMD(17), Hamilton Anxiety Scale (HAMA), and the Clinical Global Impression of Severity (CGI-S) scale.

RESULTS

The efficacy of duloxetine in switched patients did not differ significantly from that observed in untreated patients initiating duloxetine therapy (mean changes: HAMD(17) total score: -12.3 vs. -12.6; HAMA: -9.36 vs. -9.55, CGI-S: -1.94 vs. -2.12, respectively). However, the rate of discontinuation due to adverse events among patients switched to duloxetine was significantly lower than that in patients initiating duloxetine therapy (4.5% vs. 17.9%, p = .008). Treatment-emergent adverse events occurring in >or=10% of patients in both treatment groups were nausea, headache, dry mouth, insomnia, and diarrhea. Patients switched to duloxetine reported significantly lower rates of nausea and fatigue compared with patients initiating duloxetine.

CONCLUSIONS

In this study, the efficacy of duloxetine in switched patients was comparable to that observed in patients initiating duloxetine therapy. Immediate switching from an SSRI or venlafaxine to duloxetine (60 mg QD) was well tolerated.

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.

Escitalopram/reboxetine combination in depressed patients with substance use disorder

Acting pharmacologically on different transmitter systems has been suggested to have some advantages in patients with substance abuse and may possibly address a larger spectrum of symptoms. One major drawback of using antidepressants addressing several neurotransmitters is that the relative activities on the different neurotransmitters cannot individually be adjusted. Combining antidepressants targeting different neurotransmitter systems may allow adapting the effect on each neurotransmitter system corresponding to patients' response and tolerance. Three cases of patients presenting a substance use disorder with comorbid major depression episodes are presented, who were treated with a reboxetine/escitalopram combination and who showed a rapid response of their depressive syndrome.

Venlafaxine: A 2003 update

BACKGROUND

venlafaxine has been available for use as an antidepressant in the United States for a decade.

OBJECTIVE

Comprehensive reviews of venlafaxine have been published elsewhere; thus, this update focuses on newer issues of treatment remission in depression, treatment-resistant depression, and extended-release venlafaxine for generalized anxiety disorder (GAD).

METHODS

Relevant clinical literature from 1993 through 2003 was identified from database searches of MEDLINE and International Pharmaceutical Abstracts, and from manual searches of reference lists of the identified papers. Search terms included venlafaxine extended-release, venlafaxine XR, treatment-resistant depression, depressive disorders, anxiety disorders, generalized anxiety disorder, and antidepressive agents second generation.

RESULTS

With its dual action of serotonin and noradrenergic reuptake inhibition, venlafaxine has been shown to be superior in efficacy to selective serotonin reuptake inhibitors for severe major depressive disorder, treatment-resistant depression, and depressive symptom remission. Its demonstrated efficacy for both short- and long-term treatment of GAD has led to its use for obsessive-compulsive disorder and chronic pain syndromes, although inadequate clinical literature currently exists to support these latter 2 uses. In the past decade, no new or unexpected adverse events have been identified with venlafaxine therapy, except a possibly greater risk of fatal overdose compared with other serotonergic drugs, suggesting the need for caution in patients with suicidal ideation. Because venlafaxine is a potent serotonin agonist, caution must also be exercised to prevent the possibility of serotonin syndrome when used with other serotonin agonists, and its dose should be tapered very gradually to minimize the risk of a serotonin withdrawal reaction.

CONCLUSION

Venlafaxine has emerged as a successful post-SSRI-era antidepressant with an expanded range of uses since it was first marketed.

Selective serotonin reuptake inhibitors combined with venlafaxine in depressed patients who had partial response to venlafaxine: four cases

One third of depressive patients show partial or no response to antidepressant treatment. With partial or nonresponders, treatment strategies are as follows: switching to another antidepressant, augmenting with other psychotropic agents, or combining antidepressants. There are no data in the literature about the positive effect of combining venlafaxine with selective serotonin reuptake inhibitors (SSRIs). In this report, the presented cases had been on at least two different classes of antidepressant medication (or combination of antidepressants) for an adequate time and dose. They showed only a partial response to high dose of venlafaxine but improved after the addition of an SSRI (sertraline, citalopram, or paroxetine) to venlafaxine. The combination treatment was well tolerated in all of the cases.