Joseph P. Horrigan

Bupropion XL in adults with attention-deficit/hyperactivity disorder : A randomized, placebo-controlled study

BACKGROUND Data remain limited on treatment strategies for adults with attention-deficit/hyperactivity disorder (ADHD). This study evaluated the efficacy and safety of an extended-release, once-daily formulation of bupropion (XL) in the treatment of adults with ADHD. METHODS This multisite, placebo-controlled, 8-week prospective trial evaluated 162 adult patients diagnosed with ADHD (combined and inattentive types). Subjects were treated with up to 450 mg/day of bupropion XL. The primary efficacy endpoint was the proportion of ADHD responders (defined as at least a 30% reduction in the investigator-rated ADHD Rating Scale score) at week 8 (last observation carried forward [LOCF]). RESULTS Bupropion XL responders (53%) exceeded placebo responders (31%) (p =.004 at week 8) with a significantly greater proportion of bupropion XL responders as early as week 2 (p = .01). Treatment effect size calculated for the ADHD Rating Scale total score was .6. Bupropion XL appeared to provide sustained benefit throughout the day compared with placebo (morning p =.033, afternoon p =.004, evening p = .024). Bupropion XL was safe and well tolerated, with no serious or unexpected adverse events and a low rate of drug-related study discontinuation (5%). CONCLUSIONS The results from this multisite study indicate that bupropion XL is an effective and well-tolerated nonstimulant treatment for adult ADHD.

Risperidone and explosive aggressive autism

Many autistic patients with mental retardation have difficulties with explosivity and aggression. They often prove resistant to various pharmacotherapeutic interventions. In this study, 11 male outpatients (mean 18.3 years) were administered risperidone in an open-label fashion. The risperidone was started at 0.5 mg daily, and titrated upwards until maximum clinical benefit occurred. Serial clinical interviews were conducted, and Conners Parent-Teacher Questionnaires (short form) were completed by the caretakers. Substantial clinical improvement was noted almost immediately in each patient, with aggression, self-injury, explosivity, and poor sleep hygiene most improved. The modal dose for optimal response was 0.5 mg bid. Weight gain was a significant side effect (average velocity of 0.47 kg per week), while none of the patients experienced extrapyramidal side effects.

Measuring Anxiety as a Treatment Endpoint in Youth with Autism Spectrum Disorder

Despite the high rate of anxiety in individuals with autism spectrum disorder (ASD), measuring anxiety in ASD is fraught with uncertainty. This is due, in part, to incomplete consensus on the manifestations of anxiety in this population. Autism Speaks assembled a panel of experts to conduct a systematic review of available measures for anxiety in youth with ASD. To complete the review, the panel held monthly conference calls and two face-to-face meetings over a fourteen-month period. Thirty eight published studies were reviewed and ten assessment measures were examined: four were deemed appropriate for use in clinical trials, although with conditions; three were judged to be potentially appropriate, while three were considered not useful for clinical trials assessing anxiety. Despite recent advances, additional relevant, reliable and valid outcome measures are needed to evaluate treatments for anxiety in ASD.

Firategrast for relapsing remitting multiple sclerosis: a phase 2, randomised, double-blind, placebo-controlled trial

BACKGROUND Monoclonal antibody therapy against α4β-integrin is efficacious in patients with multiple sclerosis (MS) with some safety concerns. We assessed the safety and efficacy of firategrast, a small oral anti-α4β-integrin molecule, in patients with relapsing remitting MS. METHODS We did a multicentre, phase 2, randomised, double-blind, placebo-controlled, dose-ranging study in participants with clinically definite relapsing-remitting MS. A 24-week treatment period was followed by 12 weeks of core follow-up and 40 weeks of extended follow-up. Participants were randomly assigned, via computer-generated block randomisation in a 1:2:2:2 ratio, to receive one of four treatments twice a day: firategrast 150 mg, firategrast 600 mg, or firategrast 900 mg (women) or 1200 mg (men), or placebo. Brain scans were obtained at 4-week intervals to the end of core follow-up. The primary outcome was cumulative number of new gadolinium-enhancing brain lesions during the treatment phase and was analysed using a generalised linear model with an underlying negative binomial distribution, adjusted for sex, baseline number of new gadolinium-enhancing lesions, and country. This study is registered with ClinicalTrials.gov, NCT00395317. FINDINGS Of 343 individuals enrolled, 49 received firategrast 150 mg, 95 received firategrast 600 mg, 100 received firategrast 900 mg or 1200 mg, and 99 received placebo. A 49% reduction (95% CI 21·2-67·6; p=0·0026) in the cumulative number of new gadolinium-enhancing lesions was seen for the 900 mg or 1200 mg firategrast group (n=92, mean number of lesions 2·69 [SE 1·18]) versus the placebo group (90, 5·31 [1·18]). In the 600 mg group (86, 4·12 [SE 1·19]), a non-significant 22% reduction (95% CI -21·3 to 49·7; p=0·2657) occurred in mean number of new gadolinium-enhanced lesions relative to placebo; for the 150 mg group (47, 9·51 [SE 1·24]), a 79% increase (95% CI 4·1-308·1; p=0·0353) occurred relative to placebo. Firategrast was generally well tolerated at all doses. The frequency of all adverse events was similar across all treatment groups except for an increased rate of urinary tract infections in the high-dose firategrast group. No cases of progressive multifocal leukoencephalopathy or evidence of reactivation of JC virus were identified. INTERPRETATION This study showed efficacy on imaging endpoints for firategrast at the highest dose tested, and suggests that further investigation of oral short-acting α4β integrin blockade therapies is warranted. FUNDING GlaxoSmithKline.

A Randomized, Double-Blind, Placebo-Controlled, 16-Week Study of the H 3 Receptor Antagonist, GSK239512 as a Monotherapy in Subjects with Mild-to-Moderate Alzheimer’s Disease

INTRODUCTION Histaminergic H3 receptors may play a role in modulating cholinergic and monoaminergic neurotransmission. This Phase II study evaluated the efficacy and safety of GSK239512, a highly potent, brain penetrant H3 receptor antagonist as monotherapy treatment for subjects with mild-to-moderate probable Alzheimers disease (AD). METHODS In this 16-week, double-blind, randomized, parallel group study, 196 currently untreated subjects with mild-tomoderate AD (Mini Mental State Examination [MMSE] 16-24) received GSK239512 (n=97); or placebo (n=99) administered orally each morning. After a two-week placebo run-in period GSK239512 was up-titrated over 4 weeks in a flexible manner (10-20-40-80 microgram [µg]) followed by a 12-week Maintenance Phase. Co-primary efficacy endpoints were change from baseline in Episodic Memory and Executive Function/Working Memory composite scores from the CogState neuropsychological test battery (NTB) at Week 16. RESULTS Compared to placebo, GSK239512 improved Episodic Memory at Week 16 (Effect Size [ES] =0.35; p=0.0495). No statistically significant differences were observed on other cognitive domains or on clinical measures including the Alzheimers Disease Assessment Scale-Cognitive Subscale (ADASCog). GSK239512 treatment was associated with mild to moderate adverse events with headache, dizziness and events related to sleep disturbances being the most common and more pronounced in the early titration period when subjects were first being exposed to GSK239512 at the lower 10µg and 20µg doses. There were no clinically relevant changes in other safety parameters. CONCLUSION GSK239512, at doses up to 80µg/day, improved Episodic Memory in patients with mildto- moderate AD. However, no improvements were observed on Executive Function/Working Memory or other domains of cognition. No changes were observed on any of the clinical measures included as secondary endpoints (including ADAS-Cog) indicating that GSK239512 failed to show benefit in this population. GSK239512 had an acceptable safety and tolerability profile. These findings suggest that H3 antagonists may, at most, have modest and selective effects on cognitive function in patients with mild-to-moderate AD.

Measuring social communication behaviors as a treatment endpoint in individuals with autism spectrum disorder

Social communication impairments are a core deficit in autism spectrum disorder. Social communication deficit is also an early indicator of autism spectrum disorder and a factor in long-term outcomes. Thus, this symptom domain represents a critical treatment target. Identifying reliable and valid outcome measures for social communication across a range of treatment approaches is essential. Autism Speaks engaged a panel of experts to evaluate the readiness of available measures of social communication for use as outcome measures in clinical trials. The panel held monthly conference calls and two face-to-face meetings over 14 months. Key criteria used to evaluate measures included the relevance to the clinical target, coverage of the symptom domain, and psychometric properties (validity and reliability, as well as evidence of sensitivity to change). In all, 38 measures were evaluated and 6 measures were considered appropriate for use, with some limitations. This report discusses the relative strengths and weaknesses of existing social communication measures for use in clinical trials and identifies specific areas in need of further development.

Guanfacine and secondary mania in children

INTRODUCTION Guanfacine hydrochloride is an alpha-2 adrenergic agonist, which has gained recent attention in the field of child and adolescent psychiatry. This medication has been described as effective in the management of attention-deficit hyperactivity and tic disorders, with minimal side effects. METHODS Presented here are five cases of behavioral activation in children treated with guanfacine. RESULTS In each instance the clinical presentation resembled an acute hypomanic or manic episode. The dose of guanfacine was 0.5 mg/day. Later investigation revealed that all of the youngsters had clear risk factors (clinical and/or familial) for bipolar disorder. CONCLUSIONS It appears as though guanfacine may be capable of precipitating secondary mania in vulnerable children.

Measuring repetitive behaviors as a treatment endpoint in youth with autism spectrum disorder

Restricted interests and repetitive behaviors vary widely in type, frequency, and intensity among children and adolescents with autism spectrum disorder. They can be stigmatizing and interfere with more constructive activities. Accordingly, restricted interests and repetitive behaviors may be a target of intervention. Several standardized instruments have been developed to assess restricted interests and repetitive behaviors in the autism spectrum disorder population, but the rigor of psychometric assessment is variable. This article evaluated the readiness of available measures for use as outcome measures in clinical trials. The Autism Speaks Foundation assembled a panel of experts to examine available instruments used to measure restricted interests and repetitive behaviors in youth with autism spectrum disorder. The panel held monthly conference calls and two face-to-face meetings over 14 months to develop and apply evaluative criteria for available instruments. Twenty-four instruments were evaluated and five were considered “appropriate with conditions” for use as outcome measures in clinical trials. Ideally, primary outcome measures should be relevant to the clinical target, be reliable and valid, and cover the symptom domain without being burdensome to subjects. The goal of the report was to promote consensus across funding agencies, pharmaceutical companies, and clinical investigators about advantages and disadvantages of existing outcome measures.

From Trial and Error to Trial Simulation. Part 2: An Appraisal of Current Beliefs in the Design and Analysis of Clinical Trials for Antidepressant Drugs

Study design factors are partly to blame for the high failure rate in trials with antidepressant drugs. Clinical trial simulation (CTS) allows the investigation of the influence of design characteristics on important aspects of clinical trials such as power and type I error. Using CTS scenarios, we evaluated the impact of population size, randomization ratio, frequency of assessments, dropout mechanisms, clinical end point, and statistical method on the outcome of clinical trials with antidepressant drugs. The results reveal that (i) an increase in the frequency of visits does not increase statistical power, (ii) a skewed randomization for a placebo or comparator arm may decrease statistical power, and (iii) analysis of the percentage of responders should be avoided. CTS should become best practice in the optimization of study design. To date, no other statistical approach has enabled such comprehensive evaluation of the factors contributing to study failure in depression.

A Phase II study of a histamine H3 receptor antagonist GSK239512 for cognitive impairment in stable schizophrenia subjects on antipsychotic therapy

This Phase II exploratory study assessed GSK239512, a brain penetrant histamine H₃ receptor antagonist, versus placebo on cognitive impairment in 50 stable outpatients with schizophrenia. Subjects were randomized to placebo or GSK239512 for 7 weeks (4 weeks titration). GSK239512 was associated with a small positive effect size (ES) on the CogState Schizophrenia Battery (CSSB) Composite Score (ES=0.29, CI=-0.40, 0.99) relative to placebo (primary endpoint). GSK239512s ES on CSSB domains were generally positive or neutral except Processing Speed, which favored placebo (ES=-0.46). Effects on the MATRICS Consensus Cognitive Battery were mostly neutral or favored placebo. GSK239512 was generally well tolerated with an adverse event profile consistent with the known class pharmacology. There was no evidence of overall beneficial effects of GSK239512 for CIAS in this population.