Effectiveness, safety, and tolerability of lisdexamfetamine dimesylate in children with attention-deficit/hyperactivity disorder: an open-label, dose-optimization study

History of Childhood/Adolescence Referral to Speciality Care or Treatment in Adult Patients with Attention-Deficit/Hyperactivity Disorder: Mutual Relations with Clinical Presentation, Psychiatric Comorbidity and Emotional Dysregulation

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental condition that only rarely remits in adulthood. While several studies underlined differences between child and adult ADHD, the relationship between adult clinical presentation and early referral/treatment has been rarely investigated. In our study, 100 adults with ADHD were recruited and subdivided according to a history of referral to speciality care or treatment with methylphenidate (MPH) during childhood/adolescence. The early referral was associated with a history of disruptive behaviors during childhood/adolescence. Current ADHD symptoms were more pronounced in patients first referred during childhood/adolescence but never treated with MPH. Early MPH treatment was associated with lower rates of mood disorders and lower severity of emotional dysregulation at the time of assessment. Negative emotionality mediated the relationship between MPH treatment and mood disorders comorbidity. ADHD patients first referred during childhood/adolescence are characterized by more externalizing features than those first referred in adulthood. MPH treatment during the developmental age may have a role in preventing mood disorders in patients with ADHD, possibly by reducing emotional dysregulation.

Revisiting stimulant use for emotional dysregulation in attention-deficit/hyperactivity disorder (ADHD)

INTRODUCTION

Emotional dysregulation (ED) symptoms are present in a considerable portion of patients with attention-deficit/hyperactivity disorder (ADHD). In recent years, an increasing number of studies investigated the effects of stimulant medications on ED in patients with ADHD.

AREAS COVERED

A narrative review of the literature on stimulant treatment for ED is provided, including controlled and observational clinical studies conducted on pediatric and adult samples and neurobiological investigations. Positive effects of stimulants on irritability have been demonstrated in children. Comorbidity with disruptive behavior disorders (DBD) and disruptive mood dysregulation disorder does not prevent stimulant effectiveness. Methylphenidate has also been found to reduce temper problems, affective instability, and emotional over-reactivity in adults with ADHD, although with variable effect sizes. A variety of adverse emotional effects have been reported, especially at high doses and in special populations. However, several possible confounders of treatment-emergent ED have been highlighted. Finally, according to neuroimaging studies, stimulants may mitigate emotional processing anomalies associated with ADHD.

EXPERT OPINION

The findings are consistent with models including ED within the core features of ADHD. Stimulant treatment should be prioritized over antipsychotics in ADHD-DBD. It remains to be elucidated whether other medications may be more effective in specific populations with ADHD and/or ED.

Psychometric properties of the behavior rating inventory of executive function, second edition (BRIEF2) in a sample of children with ADHD in Iran

This study investigated the psychometric properties of a Persian translation of the Behavior Rating Inventory of Executive Function(BRIEF2) in 253 children with ADHD in Iran (137 boys, 116 girls)ages 8 to 12 years old (M = 10.04; SD = 1.42). The parents of the children completed the Persian BRIEF2 and the Childhood Executive Functioning Inventory (CHEXI). The findings indicated that the Persian version of BRIEF2 had good reliability (internal and test-retest) and satisfactory to good validity (convergent and construct). With respect to its construct validity, confirmatory factor analysis revealed that a three-factor solution was the best model fit for the nine subscales of the BRIEF2, which supports the valid interpretation of the three BRIEF2 indexes in the Persian BRIEF2. These findings support the clinical relevance of the Persian BRIEF in Iranian children with ADHD, as well as the multidimensional nature of executive functions.

Lisdexamfetamine and amphetamine pharmacokinetics in oral fluid, plasma, and urine after controlled oral administration of lisdexamfetamine

Lisdexamfetamine (LDX) is a long-acting prodrug stimulant indicated for the treatment of attention-deficit/hyperactivity disorder (ADHD) and binge-eating disorder (BED) symptoms. In vivo hydrolysis of the LDX amide bond releases the therapeutically active d-amphetamine (d-AMPH). This study aims to describe the pharmacokinetics of LDX and its major metabolite d-AMPH in human oral fluid, urine and plasma after a single 70 mg oral dose of LDX dimesylate. Six volunteers participated in the study. Oral fluid and blood samples were collected for up to 72 h and urine for up to 120 h post-drug administration for the pharmacokinetic evaluation of intact LDX and d-AMPH. Samples were analyzed by LC-MS/MS. Regarding noncompartmental analysis, d-AMPH reached the maximum concentration at 3.8 and 4 h post-administration in plasma and oral fluid, respectively, with a mean peak concentration value almost six-fold higher in oral fluid. LDX reached maximum concentration at 1.2 and 1.8 h post-administration in plasma and oral fluid, respectively, with a mean peak concentration value almost three-fold higher in plasma. Intact LDX and d-AMPH were detected in the three matrices. The best fit of compartmental analysis was found in the one-compartment model for both analytes in plasma and oral fluid. There was a correlation between oral fluid and plasma d-AMPH concentrations and between parent to metabolite concentration ratios over time in plasma as well as in oral fluid.

Review of lisdexamfetamine dimesylate in children and adolescents with attention deficit/hyperactivity disorder

OBJECTIVE

Lisdexamfetamine dimesylate is a stimulant prodrug with low abuse and diversion potential that is used in treatment of attention deficit hyperactivity disorder (ADHD) in children, adolescents and adults. This current literature review article aims to examine safety and efficacy of LDX in children and adolescents for the treatment of ADHD based on currently available data.

METHODS

Relevant English language articles were identified through computerized searches of the MEDLINE database (PubMed and EMBASE) and clinical trials registry up to January 2020 using the following search terms: lisdexamfetamine dimesylate, pro-drug stimulant, attention-deficit and hyperactivity disorders, ADHD, safety, efficacy, children, adolescents, Vyvanse. Forty-two articles were reviewed, 34 of which were included into this review, selected by the limit "clinical trials". This article represents the pharmacological profile, efficacy and safety data of LDX for the treatment of ADHD in children and adolescents.

RESULTS

The collection of studies reviewed identified that LDX was both safe and efficacious in the treatment of ADHD. The most commonly exhibited side effects were appetite suppression, weight loss, headache and insomnia. In comparison to placebo, LDX significantly improved ADHD symptoms and overall quality of life in children and adolescents. In comparison to atomoxetine, LDX showed statistically significant improvements in inattention, impulsivity, and activities of daily living. In comparison to OROS-MPH and placebo, LDX and OROS-MPH showed improvements with the CGI-I score, and ADHD-RS-IV, however, LDX was superior.

CONCLUSION

Patients have seen statistically significant improvements in their ADHD symptomatology in the classroom environment, health related quality of life, and their overall behavior in comparison to placebo, atomoxetine, and OROS-MPH. However, clinical judgment should be utilized when prescribing LDX due to patient specific needs and the side effect profile.

A Controlled Trial of Extended-Release Guanfacine and Psychostimulants on Executive Function and ADHD

Objective: To evaluate the effectiveness of guanfacine extended-release (GXR) versus placebo as adjunct therapy to usual care stimulant therapy in improving executive function in children aged 6 to 12 years diagnosed with ADHD. Method: In this single center, double-blind placebo-controlled crossover trial, subjects continued to take their psychostimulant and were randomly assigned at baseline to receive active treatment or placebo first. Efficacy measures included Behavioural Rating Inventory of Executive Function (BRIEF-P), ADHD Rating Scale IV (ADHD-RS IV), and Clinical Global Impressions of Severity of Illness (CGI-S) and Improvement (CGI-I) scales. Safety measures included adverse events and vital signs. Results: Significant benefits of GXR plus psychostimulant were observed on BRIEF-P (p value = .0392), ADHD-RS-IV (p < .0001), CGI-S (p = .0007), and CGI-I (p = .003). There were no serious adverse events and no new safety signals. Conclusion: Use of GXR as adjunctive therapy to stimulant therapy significantly improves executive function in children with ADHD.

Understanding the neural mechanisms of lisdexamfetamine dimesylate (LDX) pharmacotherapy in Binge Eating Disorder (BED): a study protocol

BACKGROUND

The efficacy and safety of Lisdexamfetamine dimesylate (LDX) in the treatment of moderate to severe binge eating disorder (BED) has been demonstrated in multiple randomised clinical trials. Despite this, little is known about how LDX acts to improve binge eating symptoms. This study aims to provide a comprehensive understanding of the neural mechanisms by which LDX improves symptoms of BED. We hypothesise that LDX will act by normalising connectivity within neural circuits responsible for reward and impulse control, and that this normalisation will correlate with reduced binge eating episodes.

METHODS

This is an open-label Phase 4 clinical trial of LDX in adults with moderate to severe BED. Enrolment will include 40 adults with moderate to severe BED aged 18-40 years and Body Mass Index (BMI) of 20-45 kg/m², and 22 healthy controls matched for age, gender and BMI. Clinical interview and validated scales are used to confirm diagnosis and screen for exclusion criteria, which include comorbid anorexia nervosa or bulimia nervosa, use of psychostimulants within the past 6 months, and current use of antipsychotics or noradrenaline reuptake inhibitors. Baseline assessments include clinical symptoms, multimodal neuroimaging, cognitive assessment of reward sensitivity and behavioural inhibition, and an (optional) genetic sample. A subset of these assessments are repeated after eight weeks of treatment with LDX titrated to either 50 or 70 mg. The primary outcome measures are resting-state intrinsic connectivity and the number of binge eating episodes. Analyses will be applied to resting-state fMRI data to characterise pharmacological effects across the functional connectome, and assess correlations with symptom measure changes. Comparison of neural measures between controls and those with BED post-treatment will also be performed to determine whether LDX normalises brain function.

DISCUSSION

First enrolment was in May 2018, and is ongoing. This study is the first comprehensive investigation of the neurobiological changes that occur with LDX treatment in adults with moderate to severe BED.

TRIAL REGISTRATION

ACTRN12618000623291, Australian and New Zealand Clinical Trials Registry URL: https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=374913&isReview=true. Date of Registration: 20 April 2018.

Long-Term Safety and Efficacy of Lisdexamfetamine Dimesylate in Children and Adolescents with ADHD: A Phase IV, 2-Year, Open-Label Study in Europe

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is increasingly recognized as a persistent disorder requiring long-term management.

OBJECTIVES

Our objective was to evaluate the 2-year safety and efficacy of lisdexamfetamine dimesylate (LDX) in children and adolescents with ADHD.

METHODS

Participants (aged 6-17 years) with ADHD received open-label, dose-optimized LDX 30, 50, or 70 mg/day for 104 weeks. Safety monitoring included treatment-emergent adverse events (TEAEs), vital signs, electrocardiography, and growth. The TEAEs decreased appetite, weight decrease, insomnia events (including insomnia, initial insomnia, middle insomnia, and terminal insomnia), headache, and psychiatric TEAEs were pre-defined as being of special interest. Efficacy was assessed as a secondary objective using the ADHD Rating Scale IV (ADHD-RS-IV), the Clinical Global Impressions-Improvement (CGI-I) scale, and the CGI-Severity (CGI-S) scale.

RESULTS

Of 314 participants enrolled, 191 completed the study. TEAEs were reported in 89.8% of participants, led to discontinuation in 12.4%, and were reported as serious in 8.9%. TEAEs that were reported by ≥5% of participants and considered by investigators as related to LDX were decreased appetite (49.4%), weight decrease (18.2%), insomnia (13.1%), initial insomnia (8.9%), irritability (8.6%), nausea (6.7%), headache (5.7%), and tic (5.1%). The median time to first onset and duration, respectively, of TEAEs of special interest were as follows: decreased appetite, 13.5 and 169.0 days; weight decrease, 29.0 and 225.0 days; insomnia, 17.0 and 42.8 days; and headache, 22.0 and 2.0 days. Reports of decreased appetite, weight decrease, insomnia, and headache were highest in the first 4-12 weeks. Psychiatric TEAEs were infrequent: psychosis and mania (n = 1), suicidal events (suicidal ideation, n = 2; suicide attempt, n = 1), and aggression events (aggression, n = 14; anger, n = 2; hostility, n = 1). At the last on-treatment assessment (LOTA), mean increases from baseline in vital signs were as follows: pulse rate, 7.0 bpm (95% confidence interval [CI] 5.7-8.2); systolic blood pressure (SBP), 3.4 mmHg (95% CI 2.2-4.5); and diastolic blood pressure (DBP), 3.2 mmHg (95% CI 2.2-4.2). Pre-defined thresholds for a potentially clinically important (PCI) high pulse rate were met at one or more visits by 22 participants (7.0%), for PCI high SBP were met by 45 children (22.4%) and 17 adolescents (15.2%), and for PCI high DBP were met by 78 children (38.8%) and 24 adolescents (21.4%). The mean QT interval corrected using Fridericia's formula (QTcF) decreased from baseline to LOTA (-0.6 ms [95% CI -2.3 to 1.2]; range -50 to +53). Mean changes in growth from baseline to LOTA were weight, 2.1 kg (95% CI 1.5-2.8); height, 6.1 cm (95% CI 5.6-6.7); and body mass index (BMI), -0.5 kg/m² (95% CI -0.7 to -0.3). There was a general shift to lower z score categories for height, weight, and BMI from baseline to LOTA. The mean change in ADHD-RS-IV from baseline to LOTA was -25.8 (95% CI -27.0 to -24.5) for total score, -12.6 (95% CI -13.4 to -11.9) for the hyperactivity/impulsivity subscale score, and -13.1 (95% CI -13.8 to -12.4) for the inattention subscale score. At LOTA, 77.9% of participants had a CGI-I score of 1 or 2. In addition, 77.3 and 69.2% of participants were classified as treatment responders, based on a CGI-I score of 1 or 2 and a ≥30% or ≥50% reduction from baseline in ADHD-RS-IV total score, respectively.

CONCLUSIONS

The safety profile of LDX in this longer-term study was similar to that reported in previous studies. The efficacy of LDX was maintained throughout the 2-year study period. CLINICALTRIALS.

GOV IDENTIFIER

NCT01328756.

Amphetamines for attention deficit hyperactivity disorder (ADHD) in children and adolescents

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is one of the most common psychiatric conditions affecting children and adolescents. Amphetamines are among the most commonly prescribed medications to manage ADHD. There are three main classes of amphetamines: dexamphetamine, lisdexamphetamine and mixed amphetamine salts, which can be further broken down into short- and long-acting formulations. A systematic review assessing their efficacy and safety in this population has never been conducted.

OBJECTIVES

To assess the efficacy and safety of amphetamines for ADHD in children and adolescents.

SEARCH METHODS

In August 2015 we searched CENTRAL, Ovid MEDLINE, Embase, PsycINFO, ProQuest Dissertation and Theses, and the Networked Digital Library of Theses and Dissertations. We also searched ClinicalTrials.gov, and checked the reference lists of relevant studies and reviews identified by the searches. No language or date restrictions were applied.

SELECTION CRITERIA

Parallel-group and cross-over randomized controlled trials (RCTs) comparing amphetamine derivatives against placebo in a pediatric population (< 18 years) with ADHD.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data on participants, settings, interventions, methodology, and outcomes for each included study. For continuous outcomes, we calculated the standardized mean difference (SMD) and for dichotomous outcomes we calculated the risk ratio (RR). Where possible, we conducted meta-analyses using a random-effects model. We also performed a meta-analysis of the most commonly reported adverse events in the primary studies.

MAIN RESULTS

We included 23 trials (8 parallel-group and 15 cross-over trials), with 2675 children aged three years to 17 years. All studies compared amphetamines to placebo. Study durations ranged from 14 days to 365 days, with the majority lasting less than six months. Most studies were conducted in the United States; three studies were conducted across Europe. We judged 11 included studies to be at a high risk of bias due to insufficient blinding methods, failing to account for dropouts and exclusions from the analysis, and failing to report on all outcomes defined a priori. We judged the remaining 12 studies to be at unclear risk of bias due to inadequate reporting.Amphetamines improved total ADHD core symptom severity according to parent ratings (SMD -0.57; 95% confidence interval (CI) -0.86 to -0.27; 7 studies; 1247 children/adolescents; very low quality evidence), teacher ratings (SMD -0.55; 95% CI -0.83 to -0.27; 5 studies; 745 children/adolescents; low quality evidence), and clinician ratings (SMD -0.84; 95% CI -1.32 to -0.36; 3 studies; 813 children/adolescents; very low quality evidence). In addition, the proportion of responders as rated by the Clinical Global Impression - Improvement (CGI-I) scale was higher when children were taking amphetamines (RR 3.36; 95% CI 2.48 to 4.55; 9 studies; 2207 children/adolescents; very low quality evidence).The most commonly reported adverse events included decreased appetite, insomnia/trouble sleeping, abdominal pain, nausea/vomiting, headaches, and anxiety. Amphetamines were associated with a higher proportion of participants experiencing decreased appetite (RR 6.31; 95% CI 2.58 to 15.46; 11 studies; 2467 children/adolescents), insomnia (RR 3.80; 95% CI 2.12 to 6.83; 10 studies; 2429 children/adolescents), and abdominal pain (RR 1.44; 95% CI 1.03 to 2.00; 10 studies; 2155 children/adolescents). In addition, the proportion of children who experienced at least one adverse event was higher in the amphetamine group (RR 1.30; 95% CI 1.18 to 1.44; 6 studies; 1742 children/adolescents; low quality evidence).We performed subgroup analyses for amphetamine preparation (dexamphetamine, lisdexamphetamine, mixed amphetamine salts), amphetamine release formulation (long acting versus short acting), and funding source (industry versus non industry). Between-group differences were observed for proportion of participants experiencing decreased appetite in both the amphetamine preparation (P < 0.00001) and amphetamine release formulation (P value = 0.008) subgroups, as well as for retention in the amphetamine release formulation subgroup (P value = 0.03).

AUTHORS' CONCLUSIONS

Most of the included studies were at high risk of bias and the overall quality of the evidence ranged from low to very low on most outcomes. Although amphetamines seem efficacious at reducing the core symptoms of ADHD in the short term, they were associated with a number of adverse events. This review found no evidence that supports any one amphetamine derivative over another, and does not reveal any differences between long-acting and short-acting amphetamine preparations. Future trials should be longer in duration (i.e. more than 12 months), include more psychosocial outcomes (e.g. quality of life and parent stress), and be transparently reported.

Emotional Lability in Patients with Attention-Deficit/Hyperactivity Disorder: Impact of Pharmacotherapy

Attention-deficit/hyperactivity disorder (ADHD) is a neurobehavioral disorder defined by persistent inattention and/or hyperactivity and impulsivity. These symptoms occur more frequently and are more severe in individuals with ADHD compared with those at a similar developmental level without ADHD, and can be conceptualized as deficits in executive functioning (EF). EF includes domains of metacognition and inhibition, which influence the ability to regulate responses elicited by emotional stimuli. EF deficits can lead to emotional lability (EL), which is characterized by sudden changes in emotion and behaviors of inappropriately high intensity that may include sudden bouts of anger, dysphoria, sadness, or euphoria. EL is common and estimated to occur in about 3.3-10% of the population. Recent estimates of EL prevalence in children and adolescents with ADHD range from 38 to 75%. The Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition does not include EL in diagnostic criteria for ADHD, but does include ADHD-associated features of low frustration tolerance, irritability, or mood lability. The neurobiological basis of EL is not well understood, but brain imaging studies support dividing EF into "cool" cognitive networks encompassing attention and planning activities, and "hot" motivational networks involved in temporal discounting, reward processing, and reward anticipation. Dysfunction in "hot" networks is thought to be related to EL. EL symptoms are associated with more severe ADHD and co-morbidities, have significant impact on functioning, and may respond to treatment with medications frequently used to treat ADHD. Treatment outcomes and areas for future research are discussed.

Considerations and evidence for an ADHD outcome measure

OBJECTIVE

The 2011 American Academy of Pediatrics attention-deficit/hyperactivity disorder (ADHD) guideline emphasizes monitoring and measuring outcomes of children diagnosed with ADHD; however, recommendations for how to measure improvement are less clear. A long-term goal was to develop an outcome measure that assesses the quality of care for children with ADHD. As a first step in that process, we conducted a literature synthesis on the efficacy and effectiveness of guideline-recommended ADHD treatments on patient outcomes.

METHODS

A literature search was conducted in PubMed according to PRISMA protocol and using MeSH terms. US Preventive Services Task Force (USPSTF) criteria were used to assess the level of evidence. Studies of interest were published after 2002 and assessed prospective ADHD improvement using recommended ADHD treatments.

RESULTS

The systematic review resulted in 35 studies. According to USPSTF criteria, included studies were level I (n = 24), level II-1 (n = 1), and level II-2 (n = 10) and were rated as good (n = 20) or fair (n = 15). DSM-criteria-based rating scales were used most frequently to measure ADHD treatment outcomes. All included treatments resulted in ADHD improvement. Regardless of outcome measure, tool, or treatment type, symptom reduction and improvement were relatively large, with mean percentage reductions ranging from 20% to 86% on ADHD-Behavior Rating Scales scales, with only 1 study with <25% reduction. Effect sizes ranged from 0.15 to 4.57.

CONCLUSIONS

On the basis of this literature review, a consistent pattern of improvement in pediatric ADHD patients' core symptoms emerged across studies, study designs, and recommended treatment approaches. This evidence supports the notion that an improvement of core symptoms within 1 year could satisfy the requirements of an effective outcome measure, which should be further investigated.

Contribution of rating scales to intervention for executive dysfunction

Executive dysfunction is present in children, adolescents, and adults with a wide range of clinical conditions. A growing body of literature has demonstrated the usefulness of rating scales designed to gauge executive functioning in everyday life. In this article, we discuss evidence supporting the use of such rating scales to assess intervention outcome, how they may inform development of interventions, and how comparing rater perspectives can assess awareness of cognitive dysfunction. We provide an example of how an executive function rating scale helped define intervention targets and measured outcomes in a recently published real-world intervention for children with autism spectrum disorder. Rating scales of executive function provide valuable information with respect to treatment planning and assessment of intervention outcome.

The effects of lisdexamfetamine dimesylate on emotional lability in children 6 to 12 years of age with ADHD in a double-blind placebo-controlled trial

OBJECTIVE

To evaluate the effect of lisdexamfetamine dimesylate (LDX) on emotional lability (EL) in children with ADHD.

METHOD

Post hoc analyses of a placebo-controlled trial of LDX-stratified children (aged 6-12 years) with ADHD to prominent and not prominent EL at baseline (score >3 or ≤3, respectively, on Conners' Parent Rating Scale [CPRS] items of anger, loss of temper, and irritability). Efficacy was assessed by change in CPRS EL scores and ADHD Rating Scale-IV (ADHD-RS-IV) total and subscale scores. Safety measures included treatment-emergent adverse events (TEAEs).

RESULTS

LDX showed improvement versus placebo (p < .0005) for EL item least squares (LS) mean change scores at endpoint and throughout the day. At baseline, 138 and 73 participants randomized to LDX treatment and having baseline and endpoint CPRS scores were categorized with CPRS-derived prominent and not prominent baseline EL, respectively; 41 and 31 participants randomized to placebo were categorized with CPRS-derived prominent and not prominent baseline EL, respectively. ADHD-RS-IV total and subscale scores decreased with LDX regardless of baseline EL severity. TEAEs included decreased appetite, insomnia, upper abdominal pain, headache, and irritability.

CONCLUSION

EL and ADHD symptoms improved with LDX regardless of baseline EL symptom severity. LDX demonstrated a safety profile consistent with long-acting psychostimulant use.

Attention-deficit/hyperactivity disorder with inadequate response to stimulants: approaches to management

Attention-deficit/hyperactivity disorder, or ADHD, is the most frequently occurring neurobiological disorder in childhood and is defined by symptoms of inattention and/or hyperactivity and impulsivity that are excessive when compared with other individuals at the same developmental level. ADHD can be successfully treated pharmacologically and stimulant medications are considered a first-line treatment. However, 20-35 % of subjects in clinical trials may have an inadequate response to initial stimulant treatment. There is no standard definition of inadequate response. In many clinical trials, response is defined as a percentage improvement on the Attention-Deficit/Hyperactivity Disorder Rating Scale alone, while in others the change in Clinical Global Impression-Improvement score has also been employed. Other outcome measures have also been used. A more meaningful definition for inadequate response is one that does not produce sufficient reduction of symptoms to produce functional improvement. The literature reveals many factors that may contribute to inadequate response to treatment. Among these are poor adherence, severity and/or complexity of ADHD, inadequate stimulant dosing and/or dose-limiting adverse effects. The reasons for poor adherence should be determined. Common factors include adverse effects, lack of effectiveness, concerns about addictive potential, difficulty ingesting the medication and cost. For patients with inadequate dosing, medication optimization should be tried. For those with dose-limiting adverse effects, switching to another stimulant class or a non-stimulant is an option. For patients who are partial responders to stimulants, despite adequate adherence and dose optimization, the addition of atomoxetine or guanfacine extended release or clonidine extended release may help them achieve adequate response.

The clinical impact of switching attention deficit hyperactivity disorder patients from OROS(®)-MPH to Novo-MPH ER-C(®): A paediatric practice review

OBJECTIVE

In Canada, novo-methylphenidate extended-release capsules (Novo-MPH ER-C, Novopharm Limited, Canada) was approved as being bioequivalent to a current first-line treatment for attention deficit hyperactivity disorder (ADHD), CONCERTA (OROS-MPH, Janssen Inc, Canada). The present practice review was undertaken to determine whether bioequivalence of these products translates into therapeutic equivalence.

METHODS

The present study was a retrospective, single-centre, observational review of consecutive paediatric ADHD patients prescribed OROS-MPH during a seven-month period.

RESULTS

Of the 53 patients who had been switched to the bioequivalent product, 87% destabilized and 43% indicated a shorter duration of effect. In comparison, of those who never tried the second entry medication, only 26% destabilized. Qualitative data indicated differences with regard to side effects, efficacy and duration of effect.

CONCLUSIONS

The present retrospective study indicated that Novo-MPH ER-C is not therapeutically equivalent to OROS-MPH. Once an individual with ADHD is effectively managed, disruption of their treatment should be avoided.

Analysis of individual items on the attention-deficit/hyperactivity disorder symptom rating scale in children and adults: the effects of age and sex in pivotal trials of lisdexamfetamine dimesylate

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) symptom presentation across age and sex has not been fully elucidated. The present post hoc analyses qualitatively explored the baseline levels of ADHD symptomatology across subgroups in two clinical trials of children and adults with ADHD to elucidate differences in participant presentation. The response to treatment was examined to determine patterns of response among items of the ADHD Rating Scale IV.

METHODS

Exploratory post hoc analyses of ADHD Rating Scale IV item scores were conducted on data from two 4-week placebo-controlled trials in children (6-12 years) and in adults (18-55 years) with ADHD. Baseline and endpoint mean item scores were determined for subgroups defined by age (6-9, 10-12, 18-39, and 40-55 years) and sex.

RESULTS

The baseline mean item scores were generally numerically similar for all age-by-sex subgroups. The inattention (IA) items were numerically higher than hyperactivity/impulsivity (H/I) items among older children and adults. The endpoint mean item scores were numerically lower after lisdexamfetamine dimesylate treatment for IA and H/I items in all subgroups.

CONCLUSION

These results suggest that regardless of age or sex, baseline IA and H/I symptom profiles were comparable; however, IA vs H/I symptoms were more severe in older participants. In all age-by-sex subgroups, IA and H/I symptoms appeared to decrease after active treatment.

A systematic review of the safety of lisdexamfetamine dimesylate

BACKGROUND

Here we review the safety and tolerability profile of lisdexamfetamine dimesylate (LDX), the first long-acting prodrug stimulant for the treatment of attention-deficit/hyperactivity disorder (ADHD).

METHODS

A PubMed search was conducted for English-language articles published up to 16 September 2013 using the following search terms: (lisdexamfetamine OR lisdexamphetamine OR SPD489 OR Vyvanse OR Venvanse OR NRP104 NOT review [publication type]).

RESULTS

In short-term, parallel-group, placebo-controlled, phase III trials, treatment-emergent adverse events (TEAEs) in children, adolescents, and adults receiving LDX were typical for those reported for stimulants in general. Decreased appetite was reported by 25-39 % of patients and insomnia by 11-19 %. The most frequently reported TEAEs in long-term studies were similar to those reported in the short-term trials. Most TEAEs were mild or moderate in severity. Literature relating to four specific safety concerns associated with stimulant medications was evaluated in detail in patients receiving LDX. Gains in weight, height, and body mass index were smaller in children and adolescents receiving LDX than in placebo controls or untreated norms. Insomnia was a frequently reported TEAE in patients with ADHD of all ages receiving LDX, although the available data indicated no overall worsening of sleep quality in adults. Post-marketing survey data suggest that the rate of non-medical use of LDX was lower than that for short-acting stimulants and lower than or equivalent to long-acting stimulant formulations. Small mean increases were seen in blood pressure and pulse rate in patients receiving LDX.

CONCLUSIONS

The safety and tolerability profile of LDX in individuals with ADHD is similar to that of other stimulants.

Treatment outcomes with lisdexamfetamine dimesylate in children who have attention-deficit/hyperactivity disorder with emotional control impairments

OBJECTIVE

The purpose of this study was to assess lisdexamfetamine dimesylate (LDX) treatment effects based on baseline emotional control dysfunction in children with attention-deficit/hyperactivity disorder (ADHD) categorized with or without impairments of executive function (EF) emotional control.

METHODS

Post-hoc analyses of a 7 week, open-label LDX study in children with ADHD (American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders, 4th ed., Text Revision [DSM-IV-TR] defined) and impairments in EF control of emotional response. At baseline, participants were dichotomized by Behavior Rating Inventory of EF (BRIEF) emotional control domain T-scores of ≥65 (with impairment) or <65 (without impairment). ADHD Rating Scale-IV (ADHD-RS-IV), BRIEF Global Executive Composite and emotional control domain, Expression and Emotion Scale for Children (EESC) scores, Pearson correlations for BRIEF versus ADHD-RS-IV and EESC, and Clinical Global Impressions scores were assessed at baseline and end of study (week 7)/early termination (EOS/ET) by baseline category of BRIEF emotional control impairment. Safety assessments included treatment-emergent adverse events (TEAEs).

RESULTS

At baseline and EOS/ET, respectively, 53.0% and 20.7% met criteria for emotional control impairment. Participants with and without emotional control impairments had similar ADHD-RS-IV change scores. Mean (SD) change from baseline for those with and without emotional control impairments were -20.8 (12.89) and -14.6 (11.25) for BRIEF global scores and -16.0 (13.19) and -5.0 (9.48) for BRIEF emotional control domain scores. Participants with emotional control impairments had greater mean EESC total score changes. BRIEF emotional control domain and all ADHD-RS-IV scores indicated moderate correlations between change scores (all p<0.0001). Overall, 84.9% of participants had TEAEs (mostly mild-to-moderate in severity); 3.8% discontinued because of TEAEs.

CONCLUSIONS

The proportion of children with behavioral impairments in EF control of emotional response decreased during LDX treatment. ADHD symptoms improved in both groups. The moderate correlations between EF behaviors and ADHD symptoms suggest there may be utility in evaluating behavioral domains beyond core ADHD symptoms.

A systematic review of psychostimulant treatment of negative symptoms of schizophrenia: challenges and therapeutic opportunities

BACKGROUND

Primary negative symptoms of schizophrenia (NSS) contribute heavily to functional disability and treatment of these symptoms continues to be a major unmet need even when the positive (psychotic) symptoms are controlled. The modified dopamine (DA) hypothesis posits that positive symptoms are associated with increased DA activity in the mesolimbic tract whereas NSS and cognitive symptoms are associated with decreased DA activity in the mesocortical (frontal) region. Several studies have reported improvement in NSS with DA agonist use, but with varying degrees of risk for triggering psychotic symptoms, especially in the absence of concurrent antipsychotic drug treatment. This article aims to examine older and newer evidence suggesting that psychostimulants may have a potential therapeutic role in the treatment of NSS together with a thorough review of the potential risks and benefits of psychostimulant administration in individuals with schizophrenia.

METHODS

A systematic search of relevant literature using electronic databases, reference lists, and data presented at recent meetings was conducted.

RESULTS

Improvement of NSS after psychostimulant administration is reviewed both in challenge and treatment paradigms with various agents such as methylphenidate, amphetamine, and modafinil or armodafinil. The literature points to evidence that, used adjunctively, DA agonists may improve NSS without worsening of positive symptoms in selected patients who are stable and treated with effective antipsychotic medications. Several areas of inadequate study and limitations are identified including small study samples, single-site trials, varying rigor of bias control, the dose and the duration of adjunctive psychostimulant administration, and the potential for development of tolerance.

CONCLUSION

Large, controlled clinical trials to further characterize effects of psychostimulants on NSS in carefully selected patients are warranted.

Efficacy and safety of lisdexamfetamine dimesylate in children with attention-deficit/hyperactivity disorder and recent methylphenidate use

INTRODUCTION

Lisdexamfetamine dimesylate (LDX) is a long-acting prodrug stimulant for the treatment of attention-deficit/hyperactivity disorder (ADHD). Post hoc subgroup analyses were performed from two studies in children with ADHD to compare the efficacy of LDX in participants who had received prior methylphenidate (MPH) treatment with that of the overall study populations.

METHODS

Study 1 (7-week; open-label design) and study 2 (randomized, double-blind, placebo-controlled, crossover, laboratory school design) enrolled children aged 6-12 years with ADHD and baseline ADHD Rating Scale IV (ADHD-RS-IV) total score ≥28. Both studies excluded children whose prestudy ADHD treatment provided effective control of ADHD symptoms with an acceptable safety profile. Post hoc efficacy analyses were performed in children who had received MPH within 6 months of study enrollment. Efficacy measures included the following scales: ADHD-RS-IV, Clinical Global Impressions-Improvement (CGI-I), Expression and Emotion Scale for Children (EESC), Behavior Rating Inventory of Executive Function (BRIEF), Swanson, Kotkin, Agler, M-Flynn, and Pelham (SKAMP), and Permanent Product Measure of Performance (PERMP).

RESULTS

In studies 1 and 2, 83/318 (26%) and 67/129 (52%) participants, respectively, had received MPH within 6 months and were not adequately controlled on current medication with acceptable tolerability; most of these participants had received long-acting MPH. In prior MPH participants, efficacy assessments demonstrated improvements from baseline (study 1) and versus placebo (study 2) that were comparable with those seen in the respective overall study population. Safety profiles were consistent with long-acting stimulant use.

CONCLUSION

In two studies, children who had received prior MPH treatment improved during treatment with LDX and experienced similar improvements in their symptoms as the overall study populations. For children with ADHD who were previously treated with MPH, LDX may, therefore, be an efficacious treatment option.

Metabolism of the prodrug lisdexamfetamine dimesylate in human red blood cells from normal and sickle cell disease donors

OBJECTIVES

Lisdexamfetamine dimesylate (LDX), a long-acting pro-drug psychostimulant, requires conversion to d-amphetamine for therapeutic activity. Conversion of LDX to d-amphetamine occurs primarily in the blood, specifically red blood cells (RBCs). These in vitro studies examine potential conversion in blood-containing pathologically deformed RBCs.

METHODS

Fresh blood samples from two human male donors with sickle cell disease and two healthy control donors were incubated for up to 4 h with LDX (1 µg/mL) at 37°C. LDX and d-amphetamine were measured by a validated liquid chromatographic mass spectrometric (LC/MS/MS) method.

RESULTS

In incubations of blood from the two donors with sickle cell disease, LDX concentrations declined over time such that 14.1% and 15.3% of initial LDX remained after 4 h. Similarly, in incubations of blood from two healthy donors, LDX concentrations declined over time with 13.1% and 10.5% of initial LDX remaining. Half-life of LDX was 1.30 and 1.36 h for the donors with sickle cell disease and 1.15 and 1.13 h for the healthy donors. Concurrent with the decrease in LDX concentrations, the d-amphetamine concentrations rose in a similar fashion in samples from healthy controls and sickle cell donors. d-Amphetamine levels detected at 4 h with LC/MS/MS were 297.0 ng/mL and 324.3 ng/mL in the two healthy donors and 304.5 ng/mL and 286.6 ng/mL in the two sickle cell donors.

CONCLUSIONS

While the current findings are derived from in vitro investigations on a small number of samples and the applicability of this in vitro experimental system to in vivo function has not been established, biotransformation of LDX and the resulting delivery of active d-amphetamine from LDX are likely to be similar in individuals with or without sickle cell disease.

Parent-reported executive function behaviors and clinician ratings of attention-deficit/hyperactivity disorder symptoms in children treated with lisdexamfetamine dimesylate

OBJECTIVE

The purpose of this article was to describe the relationships between parent-rated executive function (EF) and clinician-rated attention-deficit/hyperactivity disorder (ADHD) symptoms before and after lisdexamfetamine dimesylate (LDX) treatment in children with and without EF deficit.

METHODS

In post-hoc analyses of children with ADHD who participated in a 7 week open-label, dose-optimized (LDX 20-70 mg/day) trial, ADHD Rating Scale-IV (ADHD-RS-IV) change scores were compared (using two-sample t tests) between youth with and without clinically significant EF impairment at baseline. Clinically significant impairment was defined as parent-rated Behavior Rating Inventory of EF (BRIEF) Global Executive Composite (GEC) t scores ≥65. Relationships between baseline and endpoint BRIEF and ADHD-RS-IV scores were examined using Pearson correlations and generalized effect linear model. Safety assessment included treatment-emergent adverse events (TEAEs).

RESULTS

At baseline, 265/315 participants (84.1%) had a clinically significant BRIEF score. Their mean (SD) ADHD-RS-IV total score at baseline was 42.1 (6.64) for those with, and 36.5 (6.67) for those without, clinically significant BRIEF. At endpoint, ADHD-RS-IV total and subscale scores were significantly improved (p<0.0001) for both those with and those without clinically significant baseline BRIEF scores. Moderately strong, positive Pearson correlations were observed between BRIEF and ADHD-RS-IV total and subscale scores. In the generalized effect linear model, ADHD-RS-IV change scores were significantly correlated with endpoint BRIEF scores (r(2)=0.35, β=0.73, p<0.0001). In the subgroup without clinically significant BRIEF t scores at endpoint, parents and clinicians rated 90% and 95%, respectively, as improved. In the subgroup with clinically significant BRIEF t scores at endpoint, parents and clinicians rated 69% and 78%, respectively, as improved. TEAEs were experienced by 269/318 (84.9%) participants; most (82.7%) experienced events mild to moderate in intensity. A total of 12/318 (4.1%) participants discontinued because of TEAEs.

CONCLUSION

Clinically significant impairment of EF behaviors in children with ADHD was associated with more severe ADHD symptoms. LDX therapy improved ADHD symptom severity, and at endpoint, fewer participants displayed impairment of EF behaviors (versus baseline). The parent-rated BRIEF may describe clinically important EF behaviors not assessed by the 18-item ADHD-RS-IV.

Update on optimal use of lisdexamfetamine in the treatment of ADHD

Lisdexamfetamine (LDX) has been a recent addition to the treatment armamentarium for Attention Deficit Hyperactivity Disorder (ADHD). It is unique among stimulants as it is a prodrug, and has been found to be safe and well-tolerated medication in children older than 6 years, adolescents and adults. It has a smooth onset of action, exerts its action up to 13 hours and may have less rebound symptoms. LDX has proven to be effective in the treatment of ADHD in placebo controlled trials, and improved performance in simulated academic and work environments have been noticed. Both stimulant-naïve and stimulant-exposed patients with ADHD appear to benefit from LDX. It has also shown some promise in improving emotional expression and executive function of patients with ADHD. Adverse effects such as decrease in sleep, loss of appetite and others have been reported with LDX use, just as with other stimulant formulations. Since most such studies exclude subjects with preexisting cardiac morbidity, prescribing precautions should be taken with LDX in such subjects, as with any other stimulant. Study subjects on LDX have been reported to have low scores on drug likability scales, even with intravenous use; as a result, LDX may have somewhat less potential for abuse and diversion. There is a need for future studies comparing other long acting stimulants with LDX in ADHD; in fact clinical trials comparing LDX with OROS (osmotic controlled-release oral delivery system) methylphenidate are currently underway. Furthermore, the utility of this medication in other psychiatric disorders and beyond ADHD is being investigated.

Lisdexamfetamine dimesylate: a new therapeutic option for attention-deficit hyperactivity disorder

Attention-deficit hyperactivity disorder (ADHD) is associated with substantial functional, clinical and economic burdens. It is among the most common psychiatric disorders in children and adolescents, and often persists into adulthood. Both medication and psychosocial interventions are recommended for the treatment of ADHD. However, ADHD treatment practices vary considerably, depending on medication availability, reimbursement and the evolution of clinical practice in each country. In Europe, stimulants and atomoxetine are widely available medications for the treatment of ADHD, whereas in the US approved treatment options also include extended-release formulations of clonidine and guanfacine. Lisdexamfetamine dimesylate (lisdexamfetamine) is a long-acting, prodrug formulation of dexamfetamine. It is currently licensed in the US, Canada and Brazil, and is undergoing phase III studies in Europe. We performed a PubMed/MEDLINE search looking for recent (2005-2012) scientific papers regarding the pharmacokinetics, pharmacodynamics, efficacy and safety of lisdexamfetamine. The lisdexamfetamine molecule is therapeutically inactive and is enzymatically hydrolysed, primarily in the blood, to the active dexamfetamine. This conversion is unaffected by gastrointestinal pH and variations in normal transit times. Lisdexamfetamine was developed with the goal of providing an extended duration of effect that is consistent throughout the day. Clinical trials have demonstrated robust clinical efficacy of lisdexamfetamine in the treatment of children, adolescents and adults with ADHD with dose-dependent improvements in the core symptoms of ADHD. Studies have further shown that the duration of action of lisdexamfetamine continues for 13 hours post-dosing in children and for 14 hours in adults. The tolerability profile of lisdexamfetamine is consistent with those of other stimulant medications, with decreased appetite, insomnia, abdominal pain and irritability among the more frequent treatment-emergent adverse events, most of which are mild to moderate in intensity and transient in nature. There are currently no parallel-group, head-to-head trial data comparing the efficacy and safety of lisdexamfetamine with other medications for ADHD. However, the available data, including a large effect size and consistent plasma concentrations throughout the day, suggest that lisdexamfetamine is a useful treatment option for patients with ADHD.

Clinically relevant changes in emotional expression in children with ADHD treated with lisdexamfetamine dimesylate

OBJECTIVE

To describe clinically relevant effects of lisdexamfetamine dimesylate (LDX) on emotional expression (EE) in children with ADHD.

METHOD

Children with ADHD participated in a 7-week, open-label, LDX dose-optimization study. Expression and Emotion Scale for Children (EESC) change scores were analyzed post hoc using two methods to determine proportion of participants with different categories of clinical response based on (a) clinically significant (movement >2 SD from baseline mean)/reliable change (not due to measurement error) and (b) standard error of measurement (SEM) as a measure of clinically meaningful change.

RESULTS

With LDX, no participants showed clinically significant/reliable improvement; 0.7% showed clinically significant/reliable deterioration of EE by reliable change index and movement from baseline mean. One third of participants had improved EE by SEM criteria; 9.2% had categorical worsening.

CONCLUSION

Using clinically meaningful change and clinically significant/reliable change categories derived from the EESC, most participants had no worsening of EE with LDX.

Lisdexamfetamine in the treatment of adolescents and children with attention-deficit/hyperactivity disorder

Attention-deficit/hyperactivity disorder is one of the most common neurobehavioral disorders defined by developmentally inappropriate levels of inattention, hyperactivity, and impulsivity. Symptoms begin in childhood and may persist into adolescence and adulthood. Currently available pharmacological treatment options for attention-deficit/hyperactivity disorder in children and adolescents include stimulants that are efficacious and well tolerated; however, many of these preparations require multiple daily dosing and have the potential for abuse. Lisdexamfetamine dimesylate, the first prodrug stimulant, was developed to provide a longer duration of effect. It demonstrates a predictable delivery of the active drug, d-amphetamine, with low interpatient variability, and has a reduced potential for abuse. A literature search of the MEDLINE database and clinical trials register from 1995-2011, as well as relevant abstracts presented at annual professional meetings, on lisdexamfetamine dimesylate in children and adolescents were included for review. This article presents the pharmacokinetic profile, efficacy, and safety of lisdexamfetamine dimesylate for the treatment of attention-deficit/hyperactivity disorder in children and, more recently, in adolescents.

Double-blind, placebo-controlled, crossover study of the efficacy and safety of lisdexamfetamine dimesylate in college students with ADHD

OBJECTIVE

To evaluate stimulant medication on symptoms and functioning for college students with ADHD using double-blind, placebo-controlled, crossover design.

METHOD

Participants included 24 college students with ADHD and 26 college students without psychopathology. Lisdexamfetamine dimesylate (LDX) was examined for ADHD participants over five weekly phases (no-drug baseline, placebo, 30-, 50-, and 70-mg LDX per day). Self-report rating scales of functioning and direct assessment of ADHD symptoms, verbal learning/memory, and adverse side effects were collected (baseline only for control students).

RESULTS

LDX was associated with large reductions in ADHD symptoms and improvement in executive functioning along with smaller effects for psychosocial functioning. Reduction in ADHD symptoms was found for 86.4% of participants; however, large differences in symptoms and executive functioning remained relative to controls.

CONCLUSION

LDX is a safe, efficacious treatment for symptom relief in college students with ADHD. Research documenting medication effects on academic functioning and evaluating psychosocial/educational interventions is needed.

Cardiovascular risk of stimulant treatment in pediatric attention-deficit/hyperactivity disorder: update and clinical recommendations

OBJECTIVE

This review provides an update on the cardiovascular impact of therapeutic stimulant-class medication for children and adolescents with attention-deficit/hyperactivity disorder (ADHD).

METHOD

Relevant clinical literature was ascertained using PubMed searches limited to human studies and the English language as of May 2011. Current practice guidelines and consensus statements also were reviewed.

RESULTS

Stimulant-class medications for healthy children and adolescents with ADHD are associated with mean elevations in blood pressure (≤5 mmHg) and heart rate (≤10 beats/min) without changes in electrocardiographic parameters. A subset (5-15%) of children and adolescents treated may have a greater increase in heart rate or blood pressure at a given assessment or may report a cardiovascular-type complaint during stimulant treatment. It is extremely rare for a child or adolescent receiving stimulant medication to have a serious cardiovascular event during treatment, with the risk appearing similar to groups of children not receiving stimulant medication.

CONCLUSIONS

Clinicians should adhere to current recommendations regarding the prescription of stimulant medications for youth with ADHD. Scientific inquiry is indicated to identify patients at heightened risk and to continue surveillance for the longer-term cardiovascular impact of these agents.

Abnormal amygdalar activation and connectivity in adolescents with attention-deficit/hyperactivity disorder

OBJECTIVE

Emotional reactivity is one of the most disabling symptoms associated with attention-deficit/hyperactivity disorder (ADHD). We aimed to identify neural substrates associated with emotional reactivity and to assess the effects of stimulants on those substrates.

METHOD

We used functional magnetic resonance imaging (fMRI) to assess neural activity in adolescents with (n = 15) and without (n = 15) ADHD while they performed a task involving the subliminal presentation of fearful faces. Using dynamic causal modeling, we also examined the effective connectivity of two regions associated with emotional reactivity, i.e., the amygdala and the lateral prefrontal cortex (LPFC). The participants with ADHD underwent scanning both on and off stimulant medication in a counterbalanced fashion.

RESULTS

During the task, we found that activity in the right amygdala was greater in adolescents with ADHD than in control subjects. In addition, in adolescents with ADHD, greater connectivity was detected between the amygdala and LPFC. Stimulants had a normalizing effect on both the activity in the right amygdala and the connectivity between the amygdala and LPFC.

CONCLUSIONS

Our findings demonstrate that in adolescents with ADHD, a neural substrate of fear processing is atypical, as is the connectivity between the amygdala and LPFC. These findings suggest possible neural substrates for the emotional reactivity that is often present in youths with ADHD, and provide putative neural targets for the development of novel therapeutic interventions for this condition.

Advances in understanding and treating ADHD

Attention deficit hyperactivity disorder (ADHD) is a neurocognitive behavioral developmental disorder most commonly seen in childhood and adolescence, which often extends to the adult years. Relative to a decade ago, there has been extensive research into understanding the factors underlying ADHD, leading to far more treatment options available for both adolescents and adults with this disorder. Novel stimulant formulations have made it possible to tailor treatment to the duration of efficacy required by patients, and to help mitigate the potential for abuse, misuse and diversion. Several new non-stimulant options have also emerged in the past few years. Among these, cognitive behavioral interventions have proven popular in the treatment of adult ADHD, especially within the adult population who cannot or will not use medications, along with the many medication-treated patients who continue to show residual disability.

Executive function deficits in children with attention-deficit/hyperactivity disorder and improvement with lisdexamfetamine dimesylate in an open-label study

OBJECTIVE

To assess the effects of lisdexamfetamine dimesylate (LDX) on executive function (EF) behaviors in children with attention-deficit/hyperactivity disorder (ADHD).

METHODS

This observational, open-label, 7-week, dose-optimization study of LDX (20-70  mg/day) in children with ADHD evaluated efficacy with the ADHD Rating Scale IV; safety measures included adverse events (AEs). EF was assessed with the Behavior Rating Inventory of Executive Function (BRIEF). Post hoc analyses examined BRIEF scores by sex, ADHD subtype, comorbid psychiatric symptoms, and common treatment-emergent AEs (TEAEs). ADHD Rating Scale IV scores were assessed in subjects categorized by baseline BRIEF global executive composite T scores with clinically significant (≥65) or not clinically significant (<65) impairment in EF.

RESULTS

Mean (standard deviation) change from baseline to endpoint for BRIEF of -17.9 (12.5) for Global Executive Composite, -15.4 (12.6) for Behavioral Regulation Index, and -17.6 (12.3) for Metacognition Index demonstrated improvement with LDX (pooled doses; p < 0.0001 for all). Improvements in BRIEF scores were seen regardless of sex, ADHD subtype, comorbid psychiatric symptoms, common TEAEs, or baseline EF impairment category. TEAEs included decreased appetite, decreased weight, irritability, insomnia, headache, upper abdominal pain, and initial insomnia.

CONCLUSIONS

Improvements were demonstrated in EF behaviors and ADHD symptoms with LDX. LDX safety profile was consistent with long-acting stimulant use.