Identifying potential adverse events dose-response relationships via Bayesian indirect and mixed treatment comparison models.

Patients and prescribers need to be fully informed regarding the safety profile of approved medications. This includes knowledge and information regarding whether an adverse event of interest exhibits a potential dose-response relationship. In order to thoroughly evaluate whether an adverse event rate increases with increasing dose level, evidence from multiple clinical trials needs to be combined and analyzed. The various clinical trials that need to be combined often include different dose levels. If one evaluates the dose-response relationship by including only the trials with all of the common dose levels, this will lead to the exclusion of potentially several clinical trials as well as dose levels, and thus the loss of important information. Other methods, such as crudely pooling patients on the same dose level across different studies, are subject to bias due to the breakdown of randomization. It is preferable to include all studies and relevant dose levels, even if all studies do not contain the same dose levels. Bayesian methodology has been shown to be useful in the context of indirect and mixed treatment comparison methods, to combine information from different therapies in different studies in order to make treatment effect inferences. This type of approach is foundational to the models presented here, but instead of modeling different dose arms in different studies, we extend the methodology to allow for assessment of the dose-response relationship across multiple clinical trials. In this paper, we propose three Bayesian indirect/mixed treatment comparison models to assess adverse event dose-response relationships. These three models are designed to handle binary responses and time to event responses. We apply the methods to real data sets and demonstrate that our proposed methods are useful in discovering potential dose-response relationships.

Fluoxetine and adult suicidality revisited: an updated meta-analysis using expanded data sources from placebo-controlled trials.

Selective serotonin reuptake inhibitor treatments have been suggested by some to induce emergence of suicidality (ideation and behaviors). The objective of this study was to assess suicidality emergence by adverse event and rating scale data in the largest available, adult, major depression, double-blind, placebo-controlled, fluoxetine trial database (18 trials). Adverse event reports and comments for patients (fluoxetine, n = 2200; placebo, n = 1551) were searched for suicide-related events that were then classified into Food and Drug Administration categories. For 16 trials, suicidality was also examined by Hamilton Depression Scale item 3 (suicide) scores, and these data were analyzed along with the combination of event-based data and scale-based data. Comparisons between treatments were made for various estimates of worsening (risk) and improvement (benefit) of suicidality. Fluoxetine treatment did not result in greater worsening but was associated with greater improvement and faster resolution of ideation (P < or = 0.05 vs placebo). Data sources were differentially sensitive in detecting changes in suicidal ideation and behaviors. Fluoxetine treatment led to greater benefit rather than risk for suicidality.

An exploratory factor analysis of the children's depression rating scale-revised.

An exploratory factor analysis was performed in a clinical sample of 314 children and adolescents to investigate the factor structure of the Children's Depression Rating Scale-Revised (CDRS-R; Poznanski et al. 1984). A maximum likelihood method followed by a Promax rotation yielded five factors: observed depressive mood, anhedonia, morbid thoughts, somatic symptoms and reported depressive mood. The age group and gender differences on the factors scores are evaluated. After controlling for gender, the adolescents had more severe depression in terms of observed depressive mood, anhedonia, and somatic symptoms. After controlling for age groups, girls had higher scores for reported depressive mood.

Fluoxetine 40-60 mg versus fluoxetine 20 mg in the treatment of children and adolescents with a less-than-complete response to nine-week treatment with fluoxetine 10-20 mg: a pilot study.

OBJECTIVE: The aim of this study was to compare fluoxetine dosage titration to 40-60 mg/day with fixed fluoxetine 20-mg/day treatment for an additional 10 weeks in pediatric outpatients with major depressive disorder (MDD) who had not met protocol-defined response criteria after 9-week acute fluoxetine treatment. METHODS: Patients unresponsive (less than or equal to 30% decrease in Children's Depression Rating Scale-Revised [CDRS-R] score) after 9-week fluoxetine treatment were randomly reassigned to continue at 20 mg/day or to increase to 40 mg/day. After 4 weeks, patients unresponsive to 40 mg/day could receive 60 mg/day. RESULTS: Twenty-nine (29) patients, 9-17 years of age, received fluoxetine 40-60 mg/day (n = 14) or 20 mg/day (n = 15). At the conclusion of this study phase, 10 patients (71%) on 40-60 mg/day met the response criteria, versus 5 patients (36%) on 20 mg/day (p = 0.128). Mean CDRS-R scores improved in both treatment groups (fluoxetine 40-60 mg/day, -9.4; fluoxetine 20 mg/day, -1.5; p = 0.099). Adverse events were similar in both groups. However, this study phase was statistically underpowered for detecting differences between treatment groups. CONCLUSION: More than two thirds of patients whose dosage was increased responded within 10 weeks, suggesting dose escalation may benefit some patients. Approximately one third of patients unresponsive to initial treatment with fluoxetine 20 mg responded to this fixed dosage within another 10 weeks. Fluoxetine 20-60 mg/day was well tolerated.

Fluoxetine treatment for prevention of relapse of depression in children and adolescents: a double-blind, placebo-controlled study.

OBJECTIVE: To compare fluoxetine 20 to 60 mg/day with placebo for prevention of relapse of major depressive disorder in children and adolescents who had achieved Children's Depression Rating Scale, Revised scores of < or =28 during treatment with fluoxetine 20 to 60 mg. METHOD: In this 32-week relapse-prevention phase of a double-blind, multicenter, placebo-controlled 51-week study, 20 patients continued to receive their fixed dose of fluoxetine (F/F group), while 20 similar patients were switched to placebo (F/P group). Definition of relapse for the primary analysis was a Children's Depression Rating Scale, Revised score of >40 with a 2-week history of clinical deterioration or relapse in the opinion of the physician. Adverse events were compared between treatment groups to assess discontinuation-emergent adverse events. RESULTS: Mean time to relapse was longer in the F/F recipients than in the F/P recipients (p=.046). Relapse occurred in an estimated 34% in the F/F cohort and 60% in the F/P cohort. Incidence of adverse events and tolerability were similar in the F/F and F/P groups, suggesting that fluoxetine is not associated with significant discontinuation events. CONCLUSIONS: Fluoxetine 20 to 60 mg/day was well tolerated and can significantly delay relapse of major depressive disorder symptoms in children and adolescents.

Acute efficacy of fluoxetine versus sertraline and paroxetine in major depressive disorder including effects of baseline insomnia.

This study assessed whether fluoxetine, sertraline, and paroxetine differ in efficacy and tolerability in depressed patients and the impact of baseline insomnia on outcomes. Patients (N = 284) with DSM-IV major depressive disorder were randomly assigned in a double-blind fashion to fluoxetine, paroxetine, or sertraline for 10 to 16 weeks of treatment. Using the Hamilton Rating Scale for Depression (HAM-D) sleep disturbance factor score, patients were categorized into low (<4) or high (>or=4) baseline insomnia subgroups. Changes in depression and insomnia were assessed. Safety assessments included treatment-emergent adverse events (AEs), reasons for discontinuation, and AEs leading to discontinuation. In addition, AEs were evaluated within insomnia subgroups to determine emergence of activation or sedation. Depression improvement, assessed with the HAM-D-17 total score, was similar among treatments in all patients (p = 0.365) and the high (p = 0.853) and low insomnia (p = 0.415) subgroups. Insomnia improvement, assessed with the HAM-D sleep disturbance factor score, was similar among treatments in all patients (p = 0.868) and in the high (p = 0.852) and low insomnia (p = 0.982) subgroups. Analyses revealed no significant differences between treatments in the percentages of patients with substantial worsening, any worsening, worsening at endpoint, or improvement at endpoint in the HAM-D sleep disturbance factor in either insomnia subgroup. Treatments were well tolerated in most patients. No significant differences between treatments in the incidence of AEs suggestive of activation or sedation were seen in the insomnia subgroups. These data show no significant differences in acute treatment efficacy and tolerability across fluoxetine, sertraline, and paroxetine in major depressive disorder patients. Improvement in overall depression and in associated insomnia was achieved by most patients regardless of baseline insomnia.