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Concept: Venlafaxine

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Objective To study serious harms associated with selective serotonin and serotonin-norepinephrine reuptake inhibitors.Design Systematic review and meta-analysis.Main outcome measures Mortality and suicidality. Secondary outcomes were aggressive behaviour and akathisia.Data sources Clinical study reports for duloxetine, fluoxetine, paroxetine, sertraline, and venlafaxine obtained from the European and UK drug regulators, and summary trial reports for duloxetine and fluoxetine from Eli Lilly’s website.Eligibility criteria for study selection Double blind placebo controlled trials that contained any patient narratives or individual patient listings of harms.Data extraction and analysis Two researchers extracted data independently; the outcomes were meta-analysed by Peto’s exact method (fixed effect model).Results We included 70 trials (64 381 pages of clinical study reports) with 18 526 patients. These trials had limitations in the study design and discrepancies in reporting, which may have led to serious under-reporting of harms. For example, some outcomes appeared only in individual patient listings in appendices, which we had for only 32 trials, and we did not have case report forms for any of the trials. Differences in mortality (all deaths were in adults, odds ratio 1.28, 95% confidence interval 0.40 to 4.06), suicidality (1.21, 0.84 to 1.74), and akathisia (2.04, 0.93 to 4.48) were not significant, whereas patients taking antidepressants displayed more aggressive behaviour (1.93, 1.26 to 2.95). For adults, the odds ratios were 0.81 (0.51 to 1.28) for suicidality, 1.09 (0.55 to 2.14) for aggression, and 2.00 (0.79 to 5.04) for akathisia. The corresponding values for children and adolescents were 2.39 (1.31 to 4.33), 2.79 (1.62 to 4.81), and 2.15 (0.48 to 9.65). In the summary trial reports on Eli Lilly’s website, almost all deaths were noted, but all suicidal ideation events were missing, and the information on the remaining outcomes was incomplete.Conclusions Because of the shortcomings identified and having only partial access to appendices with no access to case report forms, the harms could not be estimated accurately. In adults there was no significant increase in all four outcomes, but in children and adolescents the risk of suicidality and aggression doubled. To elucidate the harms reliably, access to anonymised individual patient data is needed.

Concepts: Epidemiology, Clinical trial, Medical statistics, Antidepressant, Selective serotonin reuptake inhibitor, Sertraline, Fluoxetine, Venlafaxine

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The recent questioning of the antidepressant effect of selective serotonin reuptake inhibitors (SSRIs) is partly based on the observation that approximately half of company-sponsored trials have failed to reveal a significant difference between active drug and placebo. Most of these have applied the Hamilton depression rating scale to assess symptom severity, the sum score for its 17 items (HDRS-17-sum) serving as effect parameter. In this study, we examined whether the negative outcomes of many SSRI trials may be partly caused by the use of this frequently questioned measure of response. We undertook patient-level post-hoc analyses of 18 industry-sponsored placebo-controlled trials regarding paroxetine, citalopram, sertraline or fluoxetine, and including in total 6669 adults with major depression, the aim being to assess what the outcome would have been if the single item depressed mood (rated 0-4) had been used as a measure of efficacy. In total, 32 drug-placebo comparisons were reassessed. While 18 out of 32 comparisons (56%) failed to separate active drug from placebo at week 6 with respect to reduction in HDRS-17-sum, only 3 out of 32 comparisons (9%) were negative when depressed mood was used as an effect parameter (P<0.001). The observation that 29 out of 32 comparisons detected an antidepressant signal from the tested SSRI suggests the effect of these drugs to be more consistent across trials than previously assumed. Further, the frequent use of the HDRS-17-sum as an effect parameter may have distorted the current view on the usefulness of SSRIs and hampered the development of novel antidepressants.Molecular Psychiatry advance online publication, 28 April 2015; doi:10.1038/mp.2015.53.

Concepts: Serotonin, Antidepressant, Selective serotonin reuptake inhibitor, Major depressive disorder, Sertraline, Fluoxetine, Paroxetine, Venlafaxine

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Current antidepressants used to treat pediatric patients have the disadvantage of limited efficacy and potentially serious side effects. The purpose of this study was to assess the efficacy of vitamin C as an adjuvant agent in the treatment of pediatric major depressive disorder in a six-month, double-blind, placebo-controlled pilot trial.

Concepts: Serotonin, Citalopram, Selective serotonin reuptake inhibitor, Major depressive disorder, Sertraline, Fluoxetine, Paroxetine, Venlafaxine

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Hypericum perforatum L. (St. John’s wort) is a medicinal plant with pharmacological properties that are antidepressant, anti-inflammatory, antiviral, anti-cancer, and antibacterial. Its major active metabolites are hypericins, hyperforins, and melatonin. However, little genetic information is available for this species, especially that concerning the biosynthetic pathways for active ingredients.

Concepts: DNA, Pharmacology, Metabolism, Venlafaxine, St John's wort, Hypericum, Hyperforin, Clusiaceae

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Major depression is a highly prevalent severe mood disorder that is treated with antidepressants. The molecular targets of antidepressants require definition. We investigated the role of the acid sphingomyelinase (Asm)-ceramide system as a target for antidepressants. Therapeutic concentrations of the antidepressants amitriptyline and fluoxetine reduced Asm activity and ceramide concentrations in the hippocampus, increased neuronal proliferation, maturation and survival and improved behavior in mouse models of stress-induced depression. Genetic Asm deficiency abrogated these effects. Mice overexpressing Asm, heterozygous for acid ceramidase, treated with blockers of ceramide metabolism or directly injected with C16 ceramide in the hippocampus had higher ceramide concentrations and lower rates of neuronal proliferation, maturation and survival compared with controls and showed depression-like behavior even in the absence of stress. The decrease of ceramide abundance achieved by antidepressant-mediated inhibition of Asm normalized these effects. Lowering ceramide abundance may thus be a central goal for the future development of antidepressants.

Concepts: Serotonin, Antidepressant, Selective serotonin reuptake inhibitor, Bipolar disorder, Mood disorder, Sertraline, Fluoxetine, Venlafaxine

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BACKGROUND: The burden of rising health care expenditures has created a demand for information regarding the clinical and economic outcomes associated with Complementary and Alternative Medicines. Clinical controlled trials have found St. John’s wort to be as effective as antidepressants in the treatment of mild to moderate depression. The objective of this study was to develop a model to assess the cost-effectiveness of St. John’s wort based on this evidence. METHODS: A Markov model was constructed to estimate health and economic impacts of St. John’s wort versus antidepressants. Outcomes were treatment costs, quality-adjusted life years (QALYs) and Net Monetary Benefits (NMB). Probabilistic analyses were conducted on key model parameters. RESULTS: The average NMB across 5000 simulations identified St. John’s wort as the strategy with the highest net benefit. The total cost savings for SJW were $359.66 and $202.56 per individual for venlafaxine and sertraline respectively, with a gain of 0.08 to 0.12 QALYs over the 72 weeks of the model. LIMITATIONS: A lack of direct comparative clinical trial data comparing SJW to venlafaxine and limited data with sertraline as a comparator was a major limitation. CONCLUSIONS: In this model, St. John’s wort was shown to be a cost-effective alternative to generic antidepressants. Patients are more likely to receive treatment for a duration consistent with professional guidelines for treatment of major depression due to reduced incidence of adverse effects, improving outcomes. This represents an important option in the treatment of Major Depressive Disorder.

Concepts: Clinical trial, Selective serotonin reuptake inhibitor, Major depressive disorder, Bupropion, Sertraline, Fluoxetine, Venlafaxine, St John's wort

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The chiral signature of the antidepressant venlafaxine was used in this study to gain insight into biological attenuation processes and to differentiate abiotic and biotic transformation processes in water. Laboratory scale experiments revealed that sorption and phototransformation processes were not enantioselective while venlafaxine was enantioselectively biotransformed into O-desmethylvenlafaxine. The enantiomeric fraction (EF) variations of venlafaxine appeared to be proportional to its microbial fractional conversion. Enantioselective biotransformation of venlafaxine was also investigated in a eutrophic French river. Venlafaxine was found to be racemic at the output of the main wastewater treatment plant discharging into the river, independently of the sampling date during the year. An analysis of EF variations might provide evidence of biodegradation along a 30km river stretch.

Concepts: Microbiology, Water, Stereochemistry, Enantiomer, Sewage treatment, Citalopram, Venlafaxine, Racemic mixture

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The photodegradation and biotic transformation of the pharmaceuticals lidocaine (LDC), tramadol (TRA) and venlafaxine (VEN), and of the metabolites O-desmethyltramadol (ODT) and O-desmethylvenlafaxine (ODV) in the aquatic environmental have been investigated. Photodegradation experiments were carried out using a medium pressure Hg lamp (laboratory experiments) and natural sunlight (field experiments). Degradation of the target compounds followed a first-order kinetic model. Rates of direct photodegradation (light absorption by the compounds itself) at pH 6.9 were very low for all of the target analytes (⩽0.0059h(-1) using a Hg lamp and ⩽0.0027h(-1) using natural sunlight), while rates of indirect photodegradation (degradation of the compounds through photosensitizers) in river water at pH 7.5 were approximately 59 (LDC), 5 (TRA), 8 (VEN), 15 (ODT) and 13 times (ODV) higher than the rates obtained from the experiments in ultrapure water. The accelerated photodegradation of the target compounds in natural water is attributed mainly to the formation of hydroxyl radicals through photochemical reactions. Biotic (microbial) degradation of the target compounds in surface water has been shown to occur at very low rates (⩽0.00029h(-1)). The half-life times determined from the field experiments were 31 (LDC), 73 (TRA), 51 (VEN), 21 (ODT) and 18h (ODV) considering all possible mechanisms of degradation for the target compounds in river water (direct photodegradation, indirect photodegradation and biotic degradation).

Concepts: Water, Photochemistry, Tramadol, Venlafaxine, Prime number, Alcohols, Photochemical reaction, Surface water

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Hypericum perforatum is, with Ginkgo biloba, one of the most frequently prescribed medicinal plants in the world. Its popular name, St. John’s wort (SJW), is due to the fact that its flowers, yellow, are gathered around the feast of St. John the Baptist (24th June) whereas “wort” is an old English word for plant. Of interest, SJW possesses antidepressant actions and is currently used to alleviate symptoms of mild to moderate depression. Nearly two dozens of bioactive compounds have been isolated from SJW. Hypericin, originally described as a monoamine oxidase inhibitor type A, was thought to be responsible for the antidepressant properties of SJW extracts. However, subsequent studies could not confirm this observation and hyperforin, a phloroglucinol derivative, was shown to display antidepressive properties. Indeed, the efficiency of the extracts of SJW has been reported to be dependent on the concentration of hyperforin. However, its effects on brain cells and on the mechanisms underlying its putative clinical antidepressant effect remain poorly characterized.

Concepts: Antidepressant, Monoamine oxidase, Venlafaxine, Monoamine oxidase inhibitor, St John's wort, Hypericum, Hyperforin, Antidepressants

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Brexpiprazole is the most recently approved second-generation antipsychotic, which is used as adjunctive therapy to antidepressants for treating major depressive disorder (MDD) with inadequate response. Brexpiprazole shares pharmacological similarities with other second-generation antipsychotics, especially aripiprazole. Area covered: This review provides a detailed overview of the pre-clinical studies of brexpiprazole, followed by a summary of its clinical studies, and a comparison with other antipsychotics in MDD. Brexpiprazole is superior to placebo in reducing depressive symptoms of patients who have had an inadequate response to a standard antidepressant treatment. The efficacy of brexpiprazole is comparable to aripiprazole and quetiapine-XR, but brexpiprazole has demonstrated a lower risk for akathisia than aripiprazole and a lower risk for somnolence than quetiapine-XR. Expert opinion: Given that different studies have used different criteria to define ‘treatment-resistance’ or ‘inadequate-response’, an accurate comparison of the efficacy and safety of brexpiprazole with other antipsychotics is difficult. Preclinical data supports the premise that the antidepressant-like effects of antipsychotics are mainly due to their ability to modulate/regulate the monoamine system. Therefore, antipsychotics with similar pharmacodynamic properties like brexpiprazole could also take the ‘me too’ approach to treating MDD.

Concepts: Serotonin, Selective serotonin reuptake inhibitor, Schizophrenia, Bipolar disorder, Major depressive disorder, Sertraline, Fluoxetine, Venlafaxine