Randomized crossover study of the histamine H3 inverse agonist MK-0249 for the treatment of cognitive impairment in patients with schizophrenia

BACKGROUND

Current antipsychotic treatments have little impact on the cognitive deficits associated with schizophrenia. It has been proposed that agents which promote histamine release may enhance cognition. We evaluated whether the H3 inverse agonist MK-0249 might improve cognitive deficits in patients with schizophrenia.

METHODS

Outpatients (N=55) with schizophrenia between ages 21 and 55 who were clinically stable, experienced no more than mild to moderate overall symptoms (PANSS score total 36-75), and were taking a stable dose of antipsychotic medication were randomized to MK-0249 10mg and placebo in a multi-center, randomized, double-blind, 2-period (4-weeks per period), cross-over study. The primary efficacy endpoint was the mean change from baseline at 4-weeks of treatment in the total cognitive score on the Brief Assessment of Cognition in Schizophrenia (BACS) Battery. Other assessments of cognition were also performed.

RESULTS

A total of 46 patients completed the study. MK-0249 10mg did not demonstrate a statistically significant difference compared to placebo in the mean change from baseline in the total cognitive score on the BACS battery after 4-weeks of treatment (-0.1, 95% CI: -2.3, 2.1) or with regard to secondary measures of attention/processing speed, episodic memory, or working memory after 4-weeks of treatment. The incidence of adverse events was greater during the MK-0249 treatment period (25/52 patients, 48.1%) compared to the placebo treatment period (15/51 patients, 29.4%).

CONCLUSION

MK-0249 10mg once daily was not superior to placebo in the treatment of cognitive impairment in patients with schizophrenia after 4-weeks. (Clinicaltrials.gov: NCT00506077).

Randomized controlled study of the T-type calcium channel antagonist MK-8998 for the treatment of acute psychosis in patients with schizophrenia

OBJECTIVE

This study aimed to evaluate whether the T-type calcium channel antagonist MK-8998 was effective in treating acute psychosis in patients with schizophrenia.

METHODS

This was a randomized, double-blind, parallel-group study. After a placebo lead-in, acutely psychotic inpatients with schizophrenia were randomized to 4 weeks of MK-8998 12/16 mg daily (N = 86), olanzapine 10/15 mg daily (N = 47), or placebo (N = 83). The primary efficacy measure was score on the Positive and Negative Syndrome Scale (PANSS).

RESULTS

Out of 216 randomized patients, 158 completed the 4-week study: MK-8998 = 58 (67.4%), olanzapine = 38 (80.9%), and placebo = 62 (74.7%). The mean changes from baseline in PANSS score at week 4 for MK-8998 and olanzapine were not significantly different from placebo: MK-8998-placebo difference = -0.6 [95% confidence interval (CI): -7.0, 5.8], p = 0.9; olanzapine-placebo difference = -4.3 [95% CI: -11.7, 3.1), p = 0.3. A responder rate analysis (≥20% improvement from baseline in PANSS score) suggested an advantage of olanzapine over placebo (odds ratio = 2.20 [95% CI: 0.95, 5.09], p = 0.07) but no effect of MK-8998 over placebo (odds ratio = 1.28 [95% CI: 0.62, 2.64], p = 0.5). Treatments were generally well tolerated, but more patients reported adverse events for MK-8998 (47.7%) and olanzapine (48.9%) than placebo (37.3%).

CONCLUSIONS

MK-8998 was not effective in treating acutely psychotic inpatients with schizophrenia, as measured by PANSS score at week 4. Because of the limited efficacy of the active comparator, we cannot exclude the possibility that T-type calcium channel antagonists could prove to be effective in schizophrenia.

Orexin receptor antagonism for treatment of insomnia: a randomized clinical trial of suvorexant

OBJECTIVE

To assess the utility of orexin receptor antagonism as a novel approach to treating insomnia.

METHODS

We evaluated suvorexant, an orexin receptor antagonist, for treating patients with primary insomnia in a randomized, double-blind, placebo-controlled, 2-period (4 weeks per period) crossover polysomnography study. Patients received suvorexant (10 mg [n = 62], 20 mg [n = 61], 40 mg [n = 59], or 80 mg [n = 61]) in one period and placebo (n = 249) in the other. Polysomnography was performed on night 1 and at the end of week 4 of each period. The coprimary efficacy end points were sleep efficiency on night 1 and end of week 4. Secondary end points were wake after sleep onset and latency to persistent sleep.

RESULTS

Suvorexant showed significant (p values <0.01) dose-related improvements vs placebo on the coprimary end points of sleep efficiency at night 1 and end of week 4. Dose-related effects were also observed for sleep induction (latency to persistent sleep) and maintenance (wake after sleep onset). Suvorexant was generally well tolerated.

CONCLUSIONS

The data suggest that orexin receptor antagonism offers a novel approach to treating insomnia.

CLASSIFICATION OF EVIDENCE

This study provides Class I evidence that suvorexant improves sleep efficiency over 4 weeks in nonelderly adult patients with primary insomnia.

Long-term open-label safety study of rizatriptan acute treatment in pediatric migraineurs

OBJECTIVE

To evaluate the safety/tolerability of rizatriptan in the long-term acute treatment of migraine in pediatric patients.

BACKGROUND

Acute migraine treatment options for children are limited. A recent single-attack trial demonstrated that rizatriptan is effective in eliminating migraine headache pain in this population. We evaluated the long-term safety and efficacy of rizatriptan when used for intermittent acute treatment.

METHODS

Open-label study in pediatric migraineurs ages 12-17 years. Patients weighing <40 kg received rizatriptan (orally disintegrating tablet) 5 mg, and those weighing ≥40 kg received 10 mg. Patients could treat up to 8 mild/moderate/severe migraine attacks per month for up to 12 months. One dose of study medication was allowed in a 24-hour period.

RESULTS

A total of 674 patients were enrolled, and 606 patients were treated with study medication (N = 583 for 10 mg, N = 23 for 5 mg). The mean duration in the study was 292 days, and the mean number of doses of study medication taken was 20. Over the course of the study within 14 days post-any-dose, 66.0% (400) of the 606 treated patients had any adverse event, 2.3% (14) discontinued due to an adverse event, 2.6% (16) had a serious adverse event, and 23.4% (142) had a triptan-related adverse event. Of the 16 patients with serious adverse events within 14 days post-any-dose, the adverse events in 3 were considered drug-related; all 3 patient's adverse events were classified as serious only because they were associated with an overdose (use of >1 dose of study medication in a 24-hour period). The mean percentage of patient's attacks with pain freedom at 2-hours post-dose was 46.3%; this was relatively consistent over time (Months 1-3 = 43.7%, Months 4-6 = 51.9%, Months 7-9 = 49.9%, Months 10-12 = 49.5%).

CONCLUSION

Rizatriptan was generally safe and well tolerated in the long-term acute treatment of migraine in pediatric patients aged 12-17 years and demonstrated a consistent treatment effect over time.

Randomized controlled study of the histamine H3 inverse agonist MK-0249 in adult attention-deficit/hyperactivity disorder

BACKGROUND

It has been suggested that the histamine subtype 3 receptor inverse agonists such as MK-0249 might be effective in treating attention-deficit/hyperactivity disorder (ADHD). We evaluated the effects of MK-0249 in adults with ADHD.

METHOD

A randomized, double-blind, placebo-controlled, incomplete block, 2-period crossover study of MK-0249 5-10 mg/d and osmotic-release oral system (OROS) methylphenidate 54-72 mg/d (active comparator) was performed in 72 men and women aged ≥ 18 to ≤ 55 years who met DSM-IV criteria for ADHD of either inattentive or combined subtype and who had a chronic course of behavior disorder. The study was conducted from August 2007 through April 2008 at 6 US sites. Primary efficacy was assessed by the mean change from baseline in the Adult ADHD Investigator Symptom Rating Scale (AISRS) total score after 4 weeks of treatment.

RESULTS

Change from baseline in AISRS at week 4 for MK-0249 was not different from placebo (P = .341), whereas a significant benefit was seen for OROS methylphenidate versus placebo (P < .001). Analysis of secondary end points, including the Conners Adult ADHD Rating Scales, showed results consistent with the AISRS. A similar percentage of patients reported adverse events for MK-0249 compared with placebo (73% versus 69%, respectively). However, a greater percentage of patients reported insomnia as an adverse event with MK-0249 treatment compared with placebo (32% versus 11%, respectively).

CONCLUSIONS

MK-0249 10 mg/d is not effective for the treatment of adult ADHD.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT00475735.

Efficacy and tolerability of rizatriptan in pediatric migraineurs: Results from a randomized, double-blind, placebo-controlled trial using a novel adaptive enrichment design

Background

Treatment options for children and adolescents with migraine are limited. This study evaluated rizatriptan for the acute treatment of migraine in children and adolescents.

Methods

Randomized, double-blind, placebo-controlled, parallel-group trial in migraineurs 6–17 years old with unsatisfactory response to nonsteroidal anti-inflammatory drugs or acetaminophen/paracetamol. The trial included a double-blind run-in with weight-based rizatriptan dosing (5 mg for <40 kg, 10 mg for ≥40 kg). In the Stage 1 run-in, patients were randomized in a ratio of 20:1 placebo:rizatriptan and were instructed to treat within 30 minutes of a moderate/severe migraine. Patients with mild/no pain after 15 minutes of treatment (responders) took no further study medication, whereas patients with moderate/severe pain (non-responders) proceeded to take study medication in Stage 2. Non-responders who received placebo in Stage 1 were randomized 1:1 to rizatriptan:placebo, whereas non-responders who received rizatriptan in Stage 1 were allocated to placebo in Stage 2. The primary efficacy endpoint was pain freedom at 2 hours after Stage 2 dose in 12–17-year-olds.

Results

A higher proportion of 12–17-year-olds on rizatriptan had pain freedom at 2 hours compared with those on placebo: 87/284 (30.6%) versus 63/286 (22.0%), odds ratio = 1.55 [95% CI: 1.06 to 2.26], p = 0.025. Adverse events within 14 days of dose in 12–17-year-olds were similar for rizatriptan and placebo. The pattern of findings was similar in 6–17-year-olds.

Conclusion

Rizatriptan demonstrated a statistically significant improvement over placebo in eliminating pain and was generally well tolerated in migraineurs aged 12–17 and 6–17 years.

Trial Registration

ClinicalTrials.gov NCT01001234

Impact of responder definition on the enriched enrollment randomized withdrawal trial design for establishing proof of concept in neuropathic pain

The objective of this study was to evaluate how enrichment for responders increases assay sensitivity in an enriched enrollment randomized withdrawal (EERW) proof-of-concept (POC) study in neuropathic pain. Adults with moderate to severe peripheral neuropathic pain entered a 3- to 4-day screening period, followed by a 12-day titration to the highest tolerated dose that provided pain control (pregabalin 50-200mg t.i.d.), and then a 9-day maintenance period. Subjects were stratified as primary responders (⩾30%), secondary responders (⩾10% to <30%), or nonresponders (<10%) based on decrease in pain intensity and were randomized to placebo or pregabalin during the randomized withdrawal period. The primary endpoint was mean of average 24-h pain intensity during the last 3days of treatment period relative to the 3days before randomization. Time-to-efficacy-failure was the key secondary endpoint. Other features included not requiring discontinuation of current analgesic therapies and blinding investigators to study design elements that could contribute to non-treatment-related responses. Effect size (ES) (mean treatment difference/SD) was used to measure assay sensitivity. Pregabalin-treated subjects (n=52) had significantly less pain than those receiving placebo (n=51) (P⩽.003). Effect size of the primary endpoint was 0.72 for primary responders and decreased if secondary and nonresponders were included in the analysis. The highest ES (1.68) was demonstrated for the endpoint time-to-efficacy-failure seen in primary responders with painful diabetic neuropathy. The EERW trial design using time-to-efficacy-failure may provide a sensitive and efficient method to conduct POC studies of novel therapies in patients with neuropathic pain. Enriching a study population with patients who have achieved a 30% decrease in pain with an investigational therapy, and using time-to-efficacy-failure during the randomized withdrawal phase as the primary endpoint, can be used for a proof-of-concept study to optimize assay sensitivity and efficiently determine the analgesic potential of a new treatment for neuropathic pain.

Cerebral folate deficiency presenting as adolescent catatonic schizophrenia: a case report

Cerebral folate deficiency presents during infancy with irritability, deceleration of head growth, seizures, and progressive cognitive and motor impairment. Although low serum folate levels have been found in patients with schizophrenia, we describe the first case of cerebral folate deficiency presenting as catatonic schizophrenia. A 13-year-old previously healthy boy presented to our hospital with a 17-month history of schizophrenic symptoms with progressively worsening catatonia. On admission, he demonstrated near-complete mutism, frequent enuresis and encopresis, and severe psychomotor retardation. Our initial diagnostic evaluations, including brain magnetic resonance imaging, electroencephalogram, and routine metabolic tests, were normal. A lumbar puncture done to look for neurotransmitter defects or cerebral folate deficiency revealed low levels of 5-methyltetrahydrofolate (31 nmol/L; reference range, 40-150 nmol/L). He also had elevated titers of folate receptor-blocking antibodies. He was treated for the next 9 months with 5-formyltetrahydrofolate (folinic acid), but his catatonia was unchanged.

Tachyphylaxis after repeated antidepressant drug exposure in patients with recurrent major depressive disorder

OBJECTIVE

The aim of this post hoc analysis was to examine whether tachyphylaxis occurs after repeated courses of antidepressant drug therapy.

METHOD

276 patients with major depressive disorder (MDD) were treated with sertraline (150-200 mg daily) for 8 weeks. Patients with persistent MDD after sertraline therapy were randomized to continuation therapy with either sertraline plus atomoxetine (n = 72) or sertraline plus placebo (n = 74) for 8 additional weeks. Logistic regression was used to test the hypothesis that an increase in prior antidepressant drug exposure is associated with a reduced responsiveness to sertraline therapy.

RESULTS

The number of prior antidepressant drug exposures was negatively associated with response to initial sertraline therapy (odds ratio = 0.81, p = 0.0035). The odds ratio indicates a 19.9% reduced likelihood of response with each prior antidepressant treatment trial. In contrast, the number of prior antidepressant treatment trials was not associated with response to continuation sertraline plus atomoxetine or sertraline plus placebo therapy.

CONCLUSION

This observation supports the hypothesis that tachyphylaxis may develop after repeated antidepressant drug trials.

Practice parameter: Evaluation of the child with microcephaly (an evidence-based review): report of the Quality Standards Subcommittee of the American Academy of Neurology and the Practice Committee of the Child Neurology Society

OBJECTIVE

To make evidence-based recommendations concerning the evaluation of the child with microcephaly.

METHODS

Relevant literature was reviewed, abstracted, and classified. RECOMMENDATIONS were based on a 4-tiered scheme of evidence classification.

RESULTS

Microcephaly is an important neurologic sign but there is nonuniformity in its definition and evaluation. Microcephaly may result from any insult that disturbs early brain growth and can be seen in association with hundreds of genetic syndromes. Annually, approximately 25,000 infants in the United States will be diagnosed with microcephaly (head circumference <-2 SD). Few data are available to inform evidence-based recommendations regarding diagnostic testing. The yield of neuroimaging ranges from 43% to 80%. Genetic etiologies have been reported in 15.5% to 53.3%. The prevalence of metabolic disorders is unknown but is estimated to be 1%. Children with severe microcephaly (head circumference <-3 SD) are more likely ( approximately 80%) to have imaging abnormalities and more severe developmental impairments than those with milder microcephaly (-2 to -3 SD; approximately 40%). Coexistent conditions include epilepsy ( approximately 40%), cerebral palsy ( approximately 20%), mental retardation ( approximately 50%), and ophthalmologic disorders ( approximately 20% to approximately 50%).

RECOMMENDATIONS

Neuroimaging may be considered useful in identifying structural causes in the evaluation of the child with microcephaly (Level C). Targeted and specific genetic testing may be considered in the evaluation of the child with microcephaly who has clinical or imaging abnormalities that suggest a specific diagnosis or who shows no evidence of an acquired or environmental etiology (Level C). Screening for coexistent conditions such as cerebral palsy, epilepsy, and sensory deficits may also be considered (Level C). Further study is needed regarding the yield of diagnostic testing in children with microcephaly.

Under the radar: balamuthia amebic encephalitis

BACKGROUND

We present data from 9 years (1999-2008) of tests for Balamuthia mandrillaris, an agent of amebic encephalitis that were conducted as part of the California Encephalitis Project.

METHODS

Specimens obtained from patients with encephalitis were sent to the California Encephalitis Project for diagnostic testing; a subset of these specimens were tested for Balamuthia species. Tests included indirect immunofluorescent staining of sections for amebae, fluorescent antibody staining and enzyme-linked immunosorbent assay for serum titers, and polymerase chain reaction for Balamuthia 16S mitochondrial DNA. Cerebrospinal fluid (CSF) samples obtained from patients with diverse types of encephalitis were also tested for a broad range of cytokines.

RESULTS

Of >3500 cases referred to the California Encephalitis Project, 10 were found to be amebic encephalitis on the basis of serologic and CSF tests and examination of stained tissue sections. Most of these cases would have been described as "encephalitis of unknown origin" if it were not for the California Encephalitis Project. Nine of the 10 patients were male; ages ranged from 1.5 to 72 years. All patients had abnormal neuroimaging findings and abnormal CSF composition. The more common symptoms at presentation included headache, seizures, cranial nerve palsies, and lethargy. CSF specimens from patients with Balamuthia infection had significant elevations in the levels of cytokines IL-6 and IL-8, compared with specimens obtained from persons with viral or noninfectious encephalitides.

CONCLUSIONS

Balamuthiasis is difficult to diagnose, and it is likely that cases go unrecognized because clinicians and laboratorians are unfamiliar with the disease. Alerting the medical community to this disease may lead to earlier diagnosis and improve the chances of survival.

Long-term, open-label safety and efficacy of atomoxetine in adults with ADHD: final report of a 4-year study

OBJECTIVE

Previously, data from 97 weeks of open-label atomoxetine treatment of adults with attention-deficit/hyperactivity disorder (ADHD) were reported. This final report of that study presents results from over 4 years of treatment.

METHOD

Results were derived from the study of 384 patients (125 patients remaining in the open-label trial since the interim report), receiving up to 221 weeks of treatment. Primary efficacy measure was the Conners' Adult ADHD Rating Scale-Investigator Rated: Screening Version (CAARS-Inv:SV) Total ADHD Symptom score. Adverse events and vital signs were assessed.

RESULTS

CAARS-Inv:SV Total ADHD Symptom scores decreased 30.2% (p < .001) during treatment. Similar, significant decreases were noted for the secondary efficacy measures, including the Sheehan Disability Scale Total score, which improved 25.3% (p < .001). Adverse events consisted primarily of pharmacologically (noradrenergic) expected effects.

CONCLUSIONS

Results of this open-label study support the long-term efficacy, safety, and tolerability of atomoxetine for the treatment of adult ADHD.

Atomoxetine and osmotically released methylphenidate for the treatment of attention deficit hyperactivity disorder: acute comparison and differential response

OBJECTIVE

Response to atomoxetine, a nonstimulant norepinephrine-specific reuptake inhibitor, was compared with the effect of osmotic-release oral methylphenidate, a long-acting methylphenidate preparation, in patients with attention deficit hyperactivity disorder (ADHD).

METHOD

In a large placebo-controlled, double-blind study, patients ages 6-16 with ADHD, any subtype, were randomly assigned to receive 0.8-1.8 mg/kg per day of atomoxetine (N=222), 18-54 mg/day of osmotically released methylphenidate (N=220), or placebo (N=74) for 6 weeks. The a priori specified primary analysis compared response (at least 40% decrease in ADHD Rating Scale total score) to osmotically released methylphenidate with response to atomoxetine and placebo. After 6 weeks, patients treated with methylphenidate were switched to atomoxetine under double-blind conditions.

RESULTS

The response rates for both atomoxetine (45%) and methylphenidate (56%) were markedly superior to that for placebo (24%), but the response to osmotically released methylphenidate was superior to that for atomoxetine. Each medication was well tolerated, with completion rates and discontinuations for adverse events not significantly different from those for placebo. Of the 70 subjects who did not respond to methylphenidate, 30 (43%) subsequently responded to atomoxetine. Likewise, 29 (42%) of the 69 patients who did not respond to atomoxetine had previously responded to osmotically released methylphenidate.

CONCLUSION

Response was significantly greater with osmotically released methylphenidate than with atomoxetine. One-third of patients who received methylphenidate followed by atomoxetine responded better to one or the other, suggesting that there may be preferential responders.

The reliability and validity of self- and investigator ratings of ADHD in adults

OBJECTIVE

Little information is available comparing self- versus investigator ratings of symptoms in adult ADHD. The authors compared the reliability, validity, and utility in a sample of adults with ADHD and also as an index of clinical improvement during treatment of self- and investigator ratings of ADHD symptoms via the Conners Adult ADHD Rating Scale (CAARS).

METHOD

We analyzed data from two double-blind, parallel-design studies of 536 adult ADHD patients, randomized to 10-week treatment with atomoxetine or placebo. Outcome variables included ADHD symptom severity (CAARS self- and investigator ratings), psychiatric symptom comorbidity, and functioning.

RESULTS

All five CAARS subscales showed good internal consistency at each time point. Similarly, interrater reliability was acceptable for each subscale. Following treatment, CAARS total scores and subscale scores improved significantly from baseline. CAARS subscales also predicted changes in other psychiatric symptoms and functioning. Overall, baseline investigator ratings were stronger predictors of treatment outcome than baseline self-report scores.

CONCLUSIONS

The CAARS demonstrated good internal consistency and inter-rater reliability, as well as sensitivity to treatment outcome. The finding of greater predictive power of investigator-rated baseline scores merits further investigation.

High-dose atomoxetine treatment of ADHD in youths with limited response to standard doses

OBJECTIVE

To assess the utility and tolerability of higher than standard atomoxetine doses to treat attention-deficit/hyperactivity disorder (ADHD).

METHOD

Two randomized, double-blind trials of atomoxetine nonresponders ages 6 to 16 years were conducted comparing continued treatment with same-dose atomoxetine to treatment using greater than standard efficacious doses (study 1: up to 3.0 mg . kg . day; study 2: up to 2.4 mg . kg . day).

RESULTS

The primary outcome measure for both studies was mean ADHD Rating Scale (ADHD RS) total score. For study 1 (N = 122), decreases in ADHD RS total scores were not significantly different between treatment groups (mean change [SD]: continued same dose, -8.9 [11.2]; high dose, -9.8 [13.1]; p = .595). Likewise, for study 2 (N = 125), treatment groups did not differ (mean change [SD]: continued same dose, -6.2 [12.2]; high dose, -8.9 [10.0], p =.110). Tolerability was not significantly different between the continued same-dose and high-dose groups.

CONCLUSIONS

These studies provide evidence that current dose recommendations are appropriate for most patients, suggesting no systematic advantage to increasing atomoxetine doses beyond current guidelines. In both studies, continued treatment, whether at a higher dose or the previous dose, was associated with improved outcomes in patients who demonstrated incomplete/inadequate response to acute ADHD treatment, although without a placebo arm, we cannot rule out the possibility that expectancy played a role in symptom improvement.

Addition of atomoxetine for depression incompletely responsive to sertraline: a randomized, double-blind, placebo-controlled study

OBJECTIVE

Despite appropriate treatment with selective serotonin reuptake inhibitors (SSRIs), many depressed patients do not attain remission. Addition of a noradrenergic intervention in patients poorly or partially responsive to SSRIs may improve outcomes, but few well-controlled studies testing this hypothesis have been reported.

METHOD

Patients with major depressive disorder (confirmed by the Structured Clinical Interview for DSM-IV) were treated with sertraline at doses up to 200 mg/day in this study, conducted from June 18, 2003, to January 28, 2005. Patients who continued to experience depressive signs and symptoms after 8 weeks were randomly assigned to have atomoxetine 40 to 120 mg/day or placebo added to sertraline for a further 8 weeks.

RESULTS

Of 276 patients starting the study, 146 with persistent depressive symptoms after 8 weeks of sertraline treatment (mean [SD] final sertraline dose: 161.1 [43.4] mg/day) were randomly assigned to addition of atomoxetine or placebo. After 8 additional weeks, there was no difference between treatment groups in mean change in symptom severity or in the proportion of patients whose symptoms remitted (sertraline/ atomoxetine 29/72 [40.3%], sertraline/placebo 28/74 [37.8%], p = .865). Secondary analyses that separated the subgroups with improvements in symptoms that did not reach remission (partial responders) and those with little or no improvement (nonresponders) also showed no effect of atomoxetine. The number of patients discontinuing because of adverse events did not differ between groups.

CONCLUSION

In depressed patients with persistent symptoms after an initial trial of sertraline, addition of atomoxetine did not improve response more than placebo.

A randomized, double-blind study of continuation treatment for attention-deficit/hyperactivity disorder after 1 year

BACKGROUND

The efficacy of atomoxetine in maintaining symptom response following 1 year of treatment was assessed in children and adolescents (n = 163) with DSM-IV defined attention-deficit/hyperactivity disorder (ADHD).

METHODS

Subjects had previously responded to atomoxetine acutely and had completed 1 year of double-blind atomoxetine treatment. They were then randomly assigned in double-blind fashion to continued atomoxetine or placebo substitution for 6 months.

RESULTS

Atomoxetine was superior to placebo in preventing relapse (Wilcoxon test, p = .008) and in maintaining symptom response (ADHD Rating Scale IV score, p < .001). Among subjects assigned to discontinuation, the magnitude of symptom return was generally to a level of severity less than that observed at study entry.

CONCLUSIONS

Following 1 year of treatment with atomoxetine, continued treatment over the ensuing 6 months was associated with superior outcomes compared with placebo substitution. However, there was considerable variability between individuals in the magnitude of symptom return after drug discontinuation, suggesting that some subjects treated with atomoxetine for a year with good results may consolidate gains made during drug treatment and could benefit from a medication-free trial to assess the need for ongoing drug treatment.

CYP2D6 and clinical response to atomoxetine in children and adolescents with ADHD

BACKGROUND

Atomoxetine, a selective norepinephrine reuptake inhibitor effective in the treatment of attention-deficit/hyperactivity disorder (ADHD), is metabolized through the cytochrome P-450 2D6 (CYP2D6) enzyme pathway, which is genetically polymorphic in humans. Variations in plasma atomoxetine exposures can occur because of genetic variation or as a consequence of coadministration with drugs that inhibit CYP2D6.

METHOD

We examined the effects of CYP2D6 on the efficacy, safety, and tolerability of atomoxetine in children and adolescents using pooled data from atomoxetine clinical trials.

RESULTS

At endpoint, poor metabolizers had markedly greater reductions in mean symptom severity scores compared with extensive metabolizers (p < .05). Poor metabolizers had greater increases in heart rate and diastolic blood pressure (p < .001) and smaller increases in weight (p < .05) than extensive metabolizers. Several adverse events, including decreased appetite and tremor, were more frequent in poor metabolizers (p < .05).

CONCLUSIONS

These results suggest that CYP2D6 poor metabolizers taking atomoxetine in doses up to 1.8 mg/kg/day are likely to have greater efficacy, greater increases in cardiovascular tone, and some differences in tolerability compared with CYP2D6 extensive metabolizers taking similar doses.

Identifying pharmacodynamic protein markers of centrally active drugs in humans: a pilot study in a novel clinical model

Recognizing specific protein changes in response to drug administration in humans has the potential for significant utility in clinical research. In spite of this, many methodological and practical questions related to assessing such changes are unanswered. We conducted a series of clinical studies to assess the feasibility of measuring changes in proteins related to drug administration using a mass-spectrometry proteomics technique capable of quantifying hundreds of proteins simultaneously in cerebrospinal fluid (CSF) and plasma. Initially, the normal variability of proteins in these compartments was characterized in 16 healthy volunteers over a 2-week period. Drug-associated changes were subsequently assessed in the plasma and CSF proteomes of 11 subjects given atomoxetine, which served as a selective, centrally active probe to test the model. Protein levels in the CSF and plasma were unchanged between visits in the normal variability study. In contrast, statistically significant changes were detected in the CSF protein pattern after drug treatment. These studies suggest that identification of changes in the CSF proteome associated with the administration of centrally active drugs is feasible, and may be of value in the development of new drugs, as well as broader clinical research.

Low-dose atomoxetine for maintenance treatment of attention-deficit/hyperactivity disorder

OBJECTIVE

Data from acute studies of atomoxetine in patients with attention-deficit/hyperactivity disorder suggest that a dose of approximately 1.2 mg/kg per day is required to attain a maximal symptom response. However, lower doses could be effective during maintenance treatment, which would reduce drug exposure and potential problems related to tolerability during chronic treatment.

METHODS

Patients 6 to 16 years of age who had a robust response to an initial acute trial of atomoxetine were assigned randomly under double-blind conditions to continue treatment for up to 8 months with either the dose to which they had responded acutely (1.2-1.8 mg/kg per day, N = 116, continued same dose) or a lower dose (0.5 mg/kg per day, N = 113, low dose). The primary outcome measure was relapse, defined as an Attention-Deficit/Hyperactivity Disorder Rating Scale-IV-Parent Version: Investigator-Administered and Scored total score returned to > or = 90% of the original baseline value (before acute treatment) for 2 consecutive visits. Mean change in Attention-Deficit/Hyperactivity Disorder Rating Scale total score was assessed as a secondary outcome.

RESULTS

At randomization, symptom severity was low and similar in both groups. At end point, relapse rates did not differ between the groups. Mean change in Attention-Deficit/Hyperactivity Disorder Rating Scale total score from the conclusion of acute treatment to end point also was not different between groups. Reports of affective lability were higher in the patients in the low-dose group. Also, increases in heart rate (compared with when atomoxetine was started) were higher in the patients in the continued same-dose group than in the low-dose group. Finally, increases in weight over the course of the trial were greater for the low-dose group than the continued same-dose group.

CONCLUSIONS

For patients who experience a robust response to atomoxetine, it may be possible to retain the response during maintenance treatment with a reduced dose of atomoxetine.

Encephalopathy after whole-cell pertussis or measles vaccination: lack of evidence for a causal association in a retrospective case-control study

BACKGROUND

Whole-cell pertussis (wP) and measles vaccines are effective in preventing disease but have also been suspected of increasing the risk of encephalopathy or encephalitis. Although many countries now use acellular pertussis vaccines, wP vaccine is still widely used in the developing world. It is therefore important to evaluate whether wP vaccine increases the risk of neurologic disorders.

METHODS

A retrospective case-control study was performed at 4 health maintenance organizations. Records from January 1, 1981, through December 31, 1995, were examined to identify children aged 0 to 6 years old hospitalized with encephalopathy or related conditions. The cause of the encephalopathy was categorized as known, unknown or suspected but unconfirmed. Up to 3 controls were matched to each case. Conditional logistic regression was used to analyze the relative risk of encephalopathy after vaccination with diphtheria-tetanus-pertussis (DTP) or measles-mumps-rubella (MMR) vaccines in the 90 days before disease onset as defined by chart review compared with an equivalent period among controls indexed by matching on case onset date.

RESULTS

Four-hundred fifty-two cases were identified. Cases were no more likely than controls to have received either vaccine during the 90 days before disease onset. When encephalopathies of known etiology were excluded, the odds ratio for case children having received DTP within 7 days before onset of disease was 1.22 (95% confidence interval [CI] = 0.45-3.31, P = 0.693) compared with control children. For MMR in the 90 days before onset of encephalopathy, the odds ratio was 1.23 (95% confidence interval = 0.51-2.98, P = 0.647).

CONCLUSIONS

In this study of more than 2 million children, DTP and MMR vaccines were not associated with an increased risk of encephalopathy after vaccination.

A comparison of North American versus non-North American ADHD study populations

Few large, prospective clinical studies in Europe have assessed the validity and applicability of research methods used to study ADHD in North America. To assess comparability of study populations, we examined baseline patient characteristics from a group of North American studies against those of a large European/African/Australian study. All studies used identical diagnostic assessments and inclusion criteria, with ADHD diagnosis and the presence of comorbid psychiatric conditions confirmed using the KSADS-PL. Raters were trained and assessed to ensure uniform diagnostic and symptom severity rating standards. Six hundred and four patients (mean age = 10.2 years) enrolled in the non-North American study, and 665 patients (mean age = 10.4 years) enrolled in the North American study. The proportion of girls was higher in the North American studies (29.2% vs. 10.4%, p < 0.001). In both groups, most patients had a positive family history of ADHD and previous stimulant treatment. Fewer had the inattentive subtype of ADHD, and mean severity was slightly higher in the non-North American study. Results demonstrate that, when a uniform set of rigorous, standardized diagnostic criteria are used by skilled clinicians, the patient populations identified are generally similar. This supports the practice of generalizing results from treatment studies across geographies.

Comorbid oppositional defiant disorder and the risk of relapse during 9 months of atomoxetine treatment for attention-deficit/hyperactivity disorder

OBJECTIVE

To examine the influence of comorbid oppositional defiant disorder (ODD) on the relative risk (RR) of relapse during 9 months of treatment with atomoxetine for attention-deficit/hyperactivity disorder (ADHD).

METHOD

Four hundred and sixteen children and adolescents with ADHD whose symptoms remitted during initial 10-week, open-label atomoxetine treatment were randomly assigned to continue with atomoxetine or placebo.

RESULTS

In all, 43% met criteria for comorbid ODD. A total of 17% of patients with comorbid ODD relapsed (CGI-Severity score >or= 3 and ADHD Rating Scale total score of 90% or more of baseline at study entry on two consecutive visits) during atomoxetine treatment, compared with 26% of patients without comorbid ODD (RR 0.67, 95% CI 0.42-1.06). Mean time to relapse was not significantly different [mean (SE) days to relapse, ADHD/ +ODD: 215 (7.38); ADHD/-ODD: 211 (7.61); log rank p = 0.08]. This finding is placed within the context of atomoxetine affording an overall protection against relapse compared with placebo (RR 0.59, 95% CI 0.43-0.80).

CONCLUSIONS

Comorbid ODD does not influence the rate of relapse of patients with ADHD during longer-term treatment with atomoxetine. Atomoxetine protects against the relapse of ADHD symptoms regardless of the presence or absence of comorbid ODD.

Atomoxetine and adult attention-deficit/hyperactivity disorder: the effects of comorbidity

OBJECTIVE

The objective of this study was to determine if measures of broad clinical psychopathology or neuropsychological performance could aid in the prediction of therapeutic response to the highly selective norepinephrine transporter inhibitor, atomoxetine, among adults with attention-deficit/hyperactivity disorder (ADHD).

METHOD

We analyzed data from 2 double-blind, placebo-controlled, parallel design studies of adult patients (Study I, N = 280; Study II, N = 256) with DSM-IV-defined ADHD who were recruited by referral and advertising. Subjects were randomly assigned to 10 weeks of treatment with atomoxetine or placebo and were assessed with Conners' Adult ADHD Rating Scales (CAARS), the General Well-Being Schedule (GWB), the Sheehan Disability Scale, the Stroop Color-Word Test (SCWT), and the Structured Clinical Interview for DSM-IV (SCID) before and after treatment.

RESULTS

Therapeutic improvement on atomoxetine as evidenced by reduced CAARS scores was reliably predicted by the presence of a lifetime comorbid diagnosis of depression or post-traumatic stress disorder at baseline, while improvement on subscales of the GWB and Sheehan Disability Scale were predicted by these and other SCID endorsements, such as alcohol and substance use, as well as demographics such as age and gender. In light of the exploratory nature of this work and the many comparisons that were examined in the corresponding regression models, these findings should be regarded as tentative pending replication and extension in another dataset.

CONCLUSION

From these findings, we conclude that the variable responsiveness of individuals to atomoxetine cannot be largely accounted for by differences in broad-spectrum psychopathology or neuropsychological indicators of attentional capacity.

Efficacy of atomoxetine in adult attention-deficit/hyperactivity disorder: a drug-placebo response curve analysis

BACKGROUND

The objective of this study was to evaluate the efficacy of atomoxetine, a new and highly selective inhibitor of the norepinephrine transporter, in reducing symptoms of attention-deficit/hyperactivity disorder (ADHD) among adults by using drug-placebo response curve methods.

METHODS

We analyzed data from two double-blind, placebo-controlled, parallel design studies of adult patients (Study I, N = 280; Study II, N = 256) with DSM-IV-defined ADHD who were recruited by referral and advertising. Subjects were randomized to 10 weeks of treatment with atomoxetine or placebo, and were assessed with the Conners Adult ADHD Rating Scales and the Clinical Global Impression of ADHD Severity scale before and after treatment.

RESULTS

Those treated with atomoxetine were more likely to show a reduction in ADHD symptoms than those receiving placebo. Across all measures, the likelihood that an atomoxetine-treated subject improved to a greater extent than a placebo-treated subject was approximately 0.60. Furthermore, atomoxetine prevented worsening of most symptom classes.

CONCLUSION

From these findings, we conclude that atomoxetine is an effective treatment for ADHD among adults when evaluated using several criteria.

Atomoxetine alone or combined with fluoxetine for treating ADHD with comorbid depressive or anxiety symptoms

OBJECTIVE

Symptoms of depression and anxiety are commonly comorbid with attention-deficit/hyperactivity disorder (ADHD). The authors assessed the safety and effectiveness of atomoxetine monotherapy compared with combined atomoxetine/fluoxetine therapy in a population of children and adolescents with ADHD and concurrent symptoms of depression or anxiety.

METHOD

Patients were randomized to treatment with fluoxetine (n = 127) or placebo (n = 46) under double-blind conditions for 8 weeks, with concomitant atomoxetine use the last 5 weeks.

RESULTS

At end point, reductions in ADHD, depressive, and anxiety symptoms were marked for both treatment groups (p < .001 for the relevant scale in each symptom cluster). Some differences between treatment groups for depressive symptoms were significant, but the magnitudes of the differences were small and likely of limited clinical importance. Completion rates for the two groups were similar, as were discontinuation rates for adverse events. The combination group had greater increases in blood pressure and pulse than did the monotherapy group.

CONCLUSIONS

In pediatric patients with ADHD and comorbid symptoms of depression or anxiety, atomoxetine monotherapy appears to be effective for treating ADHD. Anxiety and depressive symptoms also improved, but the absence of a placebo-only arm does not allow us to conclude that these effects are specifically the result of treatment with atomoxetine. Combined atomoxetine/fluoxetine therapy was well tolerated.

Atomoxetine and stroop task performance in adult attention-deficit/hyperactivity disorder

OBJECTIVE

The aim of this study was to assess the efficacy of atomoxetine, a new and highly selective inhibitor of the norepinephrine transporter, for executive functioning in adults with attention-deficit/hyperactivity disorder (ADHD).

METHOD

Two identical studies using a double-blind, placebo-controlled, parallel design were conducted. Patients were adults (Study 1, n = 280; Study 2, n = 256) with Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV)-defined ADHD recruited by referral and advertising. They were randomized to 10 weeks of treatment with atomoxetine or placebo. Executive functions were measured by the Stroop task.

RESULTS

There was no evidence of cognitive deterioration associated with atomoxetine treatment. Atomoxetine treatment was associated with an improvement of the Stroop colorword score.

CONCLUSIONS

Our results provide further support for Spencer et al.'s (1998) report that atomoxetine improves inhibitory capacity, as measured by the Stroop task. The absence of cognitive deterioration from atomoxetine, along with improved performance in a subgroup of patients in this large study, supports the safety of atomoxetine in this regard and its potential for improving a significant source of impairment for adults with ADHD.

Effects of atomoxetine on growth after 2-year treatment among pediatric patients with attention-deficit/hyperactivity disorder

OBJECTIVE

Treatment for attention-deficit/hyperactivity disorder is maintained typically over periods of months or years and, as a result, the potential effects on growth of pharmacotherapy for this disorder have been an area of concern. This meta-analysis examined the effect on growth of atomoxetine, now approved in the United States for the treatment of attention-deficit/hyperactivity disorder.

METHODS

Patients (N = 412) were 6 to 16 years of age at the start of the treatment period and received atomoxetine treatment (maximal dose: 1.8 mg/kg per day) for >or=2 years. Weight and height measurements were analyzed both as actual values and after conversion to percentiles and z scores with growth charts from the Centers for Disease Control and Prevention. Expected weight and height at the end point were calculated through extrapolation from patients' baseline percentiles with the growth charts.

RESULTS

Results indicated that, after 2 years, observed weight and height were close to those predicted on the basis of the patients' baseline weight and height. Weight increased an average of 10.8 kg, a decrease relative to baseline normative weight of 2.7 percentiles, corresponding to 0.87 kg. Height increased an average of 13.3 cm, a decrease relative to baseline normative heights of 2.2 percentiles, corresponding to 0.44 cm. For both weight and height, the quartile of patients who were smallest at baseline had an increase in end-point percentile, whereas patients in the highest quartile had a decrease.

CONCLUSIONS

These findings suggested that, at the group level, there was only a minimal effect on height after 2 years of treatment with atomoxetine and, for patients most at risk (the lowest quartile), there seemed to be no effect.

Use of opioids in asphyxiated term neonates: effects on neuroimaging and clinical outcome

Perinatal asphyxia is a common cause of neurologic morbidity in neonates who are born at term. Asphyxiated neonates are frequently treated with analgesic medications, including opioids, for pain and discomfort associated with their care. On the basis of previous laboratory studies suggesting that opioids may have neuroprotective effects, we conducted a retrospective review of medical records of 52 neonates who were admitted to our neonatal intensive care unit between 1995 and 2002 and had undergone magnetic resonance imaging (MRI) of the brain. Our review revealed that 33% of neonates received morphine or fentanyl. The neonates who received opioids also had experienced hypoxic/ischemic insults of greater magnitude as suggested by higher plasma lactate levels and lower 5-min Apgar scores. It is interesting that the MRI studies of neonates who were treated with opioids during the first week of life demonstrated significantly less brain injury in all regions studied. More important, follow-up studies of a subgroup of opioid-treated neonates whose MRI scans were obtained in the second postnatal week had better long-term neurologic outcomes. Our results suggest that the use of opioids in the first week of life after perinatal asphyxia have no significant long-term detrimental effects and may increase the brain's resistance to hypoxic-ischemic insults.

Patterns of brain injury in term neonatal encephalopathy

OBJECTIVES

To determine whether the pattern of brain injury in term neonatal encephalopathy is associated with distinct prenatal and perinatal factors and to determine whether the pattern of injury is associated with 30-month neurodevelopmental outcome.

STUDY DESIGN

A total of 173 term newborns with neonatal encephalopathy from 2 centers underwent magnetic resonance imaging (MRI) at a median of 6 days of age (range, 1-24 days). Patterns of injury on MRI were defined on the basis of the predominant site of injury: watershed predominant, basal ganglia/thalamus predominant, and normal.

RESULTS

The watershed pattern of injury was seen in 78 newborns (45%), the basal ganglia/thalamus pattern was seen in 44 newborns (25%), and normal MRI studies were seen in 51 newborns (30%). Antenatal conditions such as maternal substance use, gestational diabetes, premature rupture of membranes, pre-eclampsia, and intra-uterine growth restriction did not differ across patterns. The basal ganglia/thalamus pattern was associated with more severe neonatal signs, including more intensive resuscitation at birth ( P = .001), more severe encephalopathy ( P = .0001), and more severe seizures ( P = .0001). The basal ganglia/thalamus pattern was associated with the most impaired motor and cognitive outcome at 30 months.

CONCLUSION

The patterns of brain injury in term neonatal encephalopathy are associated with different clinical presentations and neurodevelopmental outcomes. Measured prenatal risk factors did not predict the pattern of brain injury.

Atomoxetine treatment in children and adolescents with attention-deficit/hyperactivity disorder and comorbid oppositional defiant disorder

OBJECTIVE

To examine (1) moderating effects of oppositional defiant disorder (ODD) on attention-deficit/hyperactivity disorder (ADHD) treatment response and (2) responses of ODD symptoms to atomoxetine.

METHOD

Children and adolescents (ages 8-18) with ADHD were treated for approximately 8 weeks with placebo or atomoxetine (fixed dosing: 0.5, 1.2, or 1.8 mg/kg/day, b.i.d.) under randomized, double-blind conditions. Among patients with lifetime diagnostic information (n = 293), 39% were diagnosed with comorbid ODD and 61% were not. Treatment-group differences and differences between patients with and without comorbid ODD were examined post hoc for changes on the Attention-Deficit/Hyperactivity Disorder Rating Scale IV-Parent version, investigator-administered and -scored; Conners' Parent Rating Scale-Revised Short Form; Clinical Global Impressions Severity of ADHD Scale; and the parent-rated Child Health Questionnaire.

RESULTS

Youths with ADHD and comorbid ODD showed statistically significant improvement in ADHD, ODD, and quality-of-life measures. Treatment response was similar in youths with and without ODD, except that the comorbid group showed improvement compared with placebo at 1.8 mg/kg/day but not 1.2 mg/kg/day. In contrast, youths without ODD showed improvement at 1.2 mg/kg/day and no incremental benefit at 1.8 mg/kg/day.

CONCLUSIONS

Atomoxetine treatment improves ADHD and ODD symptoms in youths with ADHD and ODD, although the comorbid group may require higher doses.

Long-term, open-label study of the safety and efficacy of atomoxetine in adults with attention-deficit/hyperactivity disorder: an interim analysis

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is an early-onset neuropsychiatric disorder that affects 3% to 7% of school-age children and 4% of adults. Its pathophysiology is thought to involve the dopaminergic and nor-adrenergic pathways associated with attention control and impulsivity. These symptoms have largely been defined in the childhood population, but the course of the condition and expression in the adult population are not as well characterized.

METHOD

This is an ongoing, 3-year, open-label study consisting of adults with DSM-IV ADHD who were previously enrolled in 1 of 2 double-blind, acute-treatment studies of atomoxetine. The results of the interim analysis reported here were derived from the study of 384 patients at 31 sites who had been studied for a period of up to 97 weeks. The primary efficacy measure was the Conners' Adult ADHD Rating Scale-Investigator Rated: Screening Version (CAARS-Inv:SV) total ADHD symptom score. In addition, safety, adverse events, and vital sign measurements were assessed.

RESULTS

Significant improvement was noted with atomoxetine therapy, with mean CAARS-Inv:SV total ADHD symptom scores decreasing 33.2% from 29.2 (baseline of open-label therapy) to 19.5 (endpoint of open-label therapy) (p < .001). Similar and significant decreases were noted for the secondary efficacy measures. Adverse events consisted primarily of pharmacologically (noradrenergic) expected effects, such as increases in heart rate and blood pressure and a slight decrease in weight.

CONCLUSION

The results of this interim analysis of an ongoing, open-label study of adults with ADHD support the long-term efficacy, safety, and tolerability of atomoxetine for the treatment of adult ADHD.

Training raters to assess adult ADHD: reliability of ratings

The standardization of ADHD ratings in adults is important given their differing symptom presentation. The authors investigated the agreement and reliability of rater standardization in a large-scale trial of atomoxetine in adults with ADHD. Training of 91 raters for the investigator-administered ADHD Rating Scale (ADHDRS-IV-Inv) occurred prior to initiation of a large, 31-site atomoxetine trial. Agreement between raters on total scores was established in two ways: (a) by Kappa coefficient (rater agreement for each item with the percentage of raters that had identical item-by-item scores) and (b) intraclass correlation coefficients (reliability). For the ADHDRS-IV-Inv, rater agreement was moderate, and reliability, as measured by Cronbach's alpha, was substantial. The data indicate that clinicians can be trained to reliably evaluate ADHD in adults using the ADHDRS-IV-Inv.

ADHD Rating Scale IV: psychometric properties from a multinational study as a clinician-administered instrument

The development of rating scales for attention-deficit/hyperactivity disorder (ADHD) has traditionally focused on parent-or teacher-rated scales. However, clinician-based instruments are valuable tools for assessing ADHD symptom severity. The ADHD Rating Scale IV (ADHD RS), clinician administered and scored, has been validated as a useful instrument to assess ADHD symptoms among American children and adolescents. In this study, we assessed the psychometric properties of the scale in a recent clinical trial conducted mainly in Europe with over 600 children and adolescents diagnosed with ADHD. The trial was conducted in 11 European countries plus Australia, Israel, and South Africa. Results based on data in the study indicate that this version of the scale has acceptable psychometric properties including inter-rater reliability, test-retest reliability, internal consistency, factor structure, convergent and divergent validity, discriminant validity, and responsiveness. There were low-to-moderate ceiling and floor effects. The psychometric properties were comparable with other validated scales for assessing ADHD symptom severity. These results were consistent across the 14 countries participating in this trial. Overall, the data from this study support the use of the ADHD RS as a clinician-rated instrument for assessing the severity of ADHD symptoms in children and adolescents in Europe.

A prospective, multicenter, open-label assessment of atomoxetine in non-North American children and adolescents with ADHD

OBJECTIVE

The aim of this study was to study treatment response to atomoxetine in a large, multicenter study of non-North American patients with ADHD.

METHODS

A total of 604 children and adolescents with ADHD were enrolled in a 10-week open-label trial with atomoxetine prior to randomization to a double-blind relapse prevention phase at 33 sites in the United Kingdom, continental Europe, Israel, South Africa, and Australia. All patients had ADHD symptom severity at least 1.5 standard deviations above United States age and gender norms for their diagnostic subtype as measured by the investigator-scored ADHD Rating Scale (ADHD RS). Outcomes were assessed by analysis of change in the ADHD RS; functional and psychosocial outcomes were assessed using the Child Health Questionnaire (CHQ).

RESULTS

At endpoint, ADHD RS total scores decreased by an average of 56.7%, and 69% of patients were rated as having no or minimal symptoms. Significant improvement was observed in psychosocial and functional outcomes. Discontinuations attributed to adverse events were < 4%.

CONCLUSION

These open-label data, gathered in an international setting, add to our knowledge of the value of atomoxetine in treating ADHD symptoms, as well as its safety and tolerability.

Relapse prevention in pediatric patients with ADHD treated with atomoxetine: a randomized, double-blind, placebo-controlled study

OBJECTIVE

Attention-deficit/hyperactivity disorder (ADHD) is typically treated over extended periods; however, few placebo-controlled, long-term studies of efficacy have been reported.

METHOD

In a global multicenter study, children and adolescents who responded to an initial 12-week, open-label period of treatment with atomoxetine, a nonstimulant treatment for ADHD, were randomized to continued atomoxetine treatment or placebo for 9 months under double-blind conditions.

RESULTS

A total of 416 patients completed acute atomoxetine treatment and were randomized. At end point, atomoxetine was superior to placebo in preventing relapse defined as a return to 90% of baseline symptom severity (proportion relapsing: atomoxetine 65 of 292 [22.3%], placebo 47 of 124 [37.9%], p =.002). The proportion of patients with a 50% worsening in symptoms post-randomization was also lower on atomoxetine (atomoxetine 83 of 292 [28.4%], placebo 59 of 124 [47.6%], p <.001). Compared with patients in the placebo group, atomoxetine-treated patients had superior psychosocial functioning at end point. Discontinuations for adverse events were low in both groups, and tolerability was similar to that observed in acute treatment trials.

CONCLUSIONS

In patients who responded favorably to 12 weeks of initial treatment, atomoxetine was superior to placebo in maintaining response for the ensuing 9 months. This result supports the value of maintenance treatment with atomoxetine in patients with ADHD who respond to initial treatment.

The link between health-related quality of life and clinical symptoms among children with attention-deficit hyperactivity disorder

Clinical research on attention-deficit hyperactivity disorder (ADHD) has begun to integrate measures of health-related quality of life (HRQL) as part of the overall assessment of treatment outcomes. This study examines the association between HRQL and measures of clinical symptoms of ADHD. Data were gathered from 297 children and adolescents in an 8-week, randomized, double-blind, placebo-controlled, clinical trial of atomoxetine treatment for ADHD. HRQL was assessed with the Child Health Questionnaire 50-item Parent Form. ADHD symptoms were assessed with the ADHD Rating Scale-IV; Parent Version and Clinical Global Impressions-ADHD-Severity. Associations between HRQL and clinical symptoms were assessed with correlations, analyses of variance with post hoc comparisons, and t tests. The Child Health Questionnaire 50-item Parent Form scales assessing psychosocial domains of HRQL were significantly negatively correlated with clinical measures. Improvement in clinical symptoms was associated with corresponding improvement in psychosocial aspects of HRQL. The findings suggest that HRQL instruments can add important information to efficacy measures in clinical trials of ADHD treatment.

Long-term treatment outcomes of depression with associated anxiety: efficacy of continuation treatment with fluoxetine

BACKGROUND

Severity of anxiety does not appear to influence the antidepressant response to fluoxetine during acute treatment of major depressive disorder (MDD). We report a retrospective pooled analysis of 2 studies to assess the effect of associated anxiety on the efficacy of fluoxetine in the continuation treatment phase of MDD.

METHOD

Patients whose MDD remitted (study 1) or responded (study 2) after approximately 12 to 13 weeks of open-label treatment with fluoxetine 20 mg daily were randomly assigned in double-blind fashion to placebo, continued treatment with fluoxetine 20 mg daily, or, in study 2 only, treatment with enteric-coated fluoxetine 90 mg once weekly, for at least 25 weeks. Both studies included male and female outpatients who met criteria for MDD as assessed by DSM-III-R (study 1) or DSM-IV (study 2). Patients were categorized into high anxiety (> or = 7) or low anxiety (< 7) subgroups based on baseline Hamilton Rating Scale for Depression (HAM-D) anxiety/somatization subfactor scores. Subgroups were compared by therapy for time from randomization to relapse and change in efficacy scores.

RESULTS

No significant differences in time to relapse were observed between anxiety subgroups in either active treatment group. However, in patients switched to placebo for continuation treatment, the high anxiety subgroup had a significantly higher risk of relapse than those with low anxiety (risk ratio = 1.63, p =.013). Significant differences between anxiety groups were seen in change in HAM-D anxiety/somatization subfactor scores in the fluoxetine 20 mg and placebo treatment groups, and in change in HAM-D-17 scores in the placebo treatment group (p <.05).

CONCLUSION

Although high baseline anxiety does not appear to impact the benefit of continuation therapy with fluoxetine, it does appear to predict increased risk of relapse in individuals who do not remain on antidepressant therapy for the duration of continuation treatment.

Changes in symptoms and adverse events after discontinuation of atomoxetine in children and adults with attention deficit/hyperactivity disorder: a prospective, placebo-controlled assessment

Drugs that affect neurotransmitter release can induce changes in neuroregulation during chronic administration. Thus, in addition to recurrence of symptoms of the illness, discontinuation of treatment can be associated with clinical signs and symptoms related to these changes. Atomoxetine, a new drug approved in the United States for treatment of attention deficit/hyperactivity disorder (ADHD), is associated with blockade of the presynaptic norepinephrine transporter. Because treatment of ADHD typically involves chronic treatment, the potential for production of a discontinuation syndrome as well as recurrence of symptoms upon drug discontinuation were assessed as part of the clinical development process. The effects of discontinuation of atomoxetine were assessed in children and adults with ADHD following 9 to 10 weeks of continuous therapy in 4 large studies. Symptoms of ADHD worsened following drug discontinuation but did not return to pretreatment levels. The incidence of discontinuation-emergent adverse events was low and there were no statistically significant differences between the patients abruptly discontinuing from atomoxetine and those continuing on placebo. Discontinuation of atomoxetine did not result in the development of an acute discontinuation syndrome and was well tolerated. It appears that atomoxetine may be discontinued without risk for symptom rebound or discontinuation-emergent adverse effects. Tapering of doses is not necessary when atomoxetine is discontinued.