Use Of XR Research Articles

Differential use of extended and immediate release quetiapine: a retrospective registry study of Finnish inpatients with schizophrenia spectrum and bipolar disorders

ObjectiveExtended release (XR) and immediate release (IR) quetiapine have differing dosing, titration and plasma concentration profiles. The authors assessed whether the use of quetiapine XR and IR in schizophrenia spectrum...

Quetiapine XR efficacy and tolerability as monotherapy and as adjunctive treatment to conventional antidepressants in the acute and maintenance treatment of major depressive disorder: a review of registration trials

Results from pivotal registration trials in major depressive disorder cohere with outcomes from effectiveness studies indicating that the majority of individuals receiving single-agent pharmacotherapy fail to achieve and sustain symptomatic remission. Several factors provided the impetus for this review: suboptimal efficacy with existing pharmacotherapy for major depressive disorder, quetiapine XR efficacy in the acute and maintenance treatment of bipolar depression, emerging pharmacodynamic evidence that quetiapine XR (and/or its metabolites) uniquely engages monoaminergic systems salient to symptom relief in depressive syndromes, the increasing use of second-generation antipsychotics in the treatment of major depressive disorder and the recent FDA review of quetiapine XR in major depressive disorder. Studies reviewed herein are pivotal registration trials that evaluated the acute and maintenance efficacy and tolerability of quetiapine XR (as monotherapy and as adjunctive treatment) in major depressive disorder. In addition, we also review recent investigations characterizing the pharmacodynamic effect of quetiapine's principal active metabolite, norquetiapine. All studies were obtained from AstraZeneca (Wilmington, DE, USA) and have been presented at national/international scientific meetings. Taken together, extant studies demonstrated that quetiapine XR (50 – 300 mg) provides rapid and sustained symptomatic improvement in the acute and maintenance treatment of major depressive disorder. Quetiapine XR may also offer advantages relative to duloxetine in time to onset of antidepressant action. The major limitations of quetiapine XR use in major depressive disorder relate to weight gain and disrupted glucose/lipid homeostasis as well as sedation/somnolence. Quetiapine XR has tolerability advantages compared with duloxetine on measures of sexual dysfunction. The data from the studies reviewed herein also indicate that quetiapine XR poses a low risk for extrapyramidal side effects in middle-aged and elderly individuals with major depressive disorder.

Venlafaxine Extended Release in Pediatric Anxiety and Depression

Venlafaxine extended release (XR) is the once-daily preparation of venlafaxine, which inhibits the reuptake of serotonin and norepinephrine. At lower doses, venlafaxine XR preferentially blocks the reuptake of serotonin, while at higher doses it blocks the reuptake of serotonin and norepinephrine. Although venlafaxine XR is not approved for pediatric use, it is increasingly being used in the treatment of pediatric anxiety and depressive disorders. While in the past several years there have been numerous randomized, placebo-controlled trials in pediatric generalized and social anxiety and depression, more studies are needed to determine when the utilization of venlafaxine XR in the pediatric population is warranted. Results from completed studies show improvement in generalized and social anxiety symptoms in children and adolescents, but only minimal improvement in depressive symptoms in adolescents, with no improvement in children. Gastrointestinal symptoms are the most commonly reported adverse events. Venlafaxine XR may affect weight, heart rate and blood pressure in the short-term, while its long-term effects are unknown. The most recent and comprehensive meta-analysis reports a 4% risk difference of suicidal ideation/attempt for venlafaxine XR versus placebo in depression trials, and a 1% risk difference for generalized and social anxiety studies. This paper will review available data regarding the safety and efficacy of venlafaxine XR use in the pediatric population, as well as the pharmacokinetics and pharmacodynamics of this medication.