Placebo-controlled evaluation of amphetamine mixture-dextroamphetamine salts and amphetamine salts (Adderall): efficacy rate and side effects

Effect of CYP2D6 genetic variation on patient-reported symptom improvement and side effects among children and adolescents treated with amphetamines

OBJECTIVES

Amphetamine-based medications are recommended as a first-line pharmacotherapy for the treatment of attention-deficit/hyperactivity disorder in children and adolescents. However, the efficacy and tolerability of these medications vary across individuals, which could be related to interindividual differences in amphetamine metabolism. This study examined if genotype-predicted phenotypes of the cytochrome P450 isozyme CYP2D6 were associated with self-reported side effects and symptom improvement in youth treated with amphetamines.

METHODS

Two hundred fourteen participants aged 6-24 who had a history of past or current amphetamine treatment were enrolled from Western Canada. Amphetamine dose and duration information was collected from the participants along with questions regarding adherence, concomitant medications, symptom improvement and side effects. DNA was extracted from saliva samples and genotyped for CYP2D6 . Binomial logistic regression models were used to determine the effect of CYP2D6 metabolizer phenotype with and without correction for phenoconversion on self-reported symptom improvement and side effects.

RESULTS

Genotype-predicted CYP2D6 poor metabolizers had significantly higher odds of reporting symptom improvement when compared to intermediate metabolizers (OR = 3.67, 95% CI = 1.15-11.7, P  = 0.029) after correction for phenoconversion and adjusting for sex, age, dose, duration, and adherence. There was no association between CYP2D6 metabolizer phenotype and self-reported side effects.

CONCLUSION

Our findings indicate that phenoconverted and genotype-predicted CYP2D6 poor metabolizer phenotype is significantly associated with higher odds of symptom improvement in children and adolescents treated with amphetamine. If replicated, these results could inform the development of future dosing guidelines for amphetamine treatment in children and adolescents.

Viloxazine, a Non-stimulant Norepinephrine Reuptake Inhibitor, for the Treatment of Attention Deficit Hyperactivity Disorder: A 3 Year Update

Attention deficit hyperactivity disorder (ADHD) is the most common neurodevelopmental disorder in childhood. Current treatment options for ADHD include pharmacological treatment (stimulants, non-stimulants, anti-depressants, anti-psychotics), psychological treatment (behavioral therapy with or without parent training, cognitive training, neurofeedback), and complementary and alternative therapies (vitamin supplementation, exercise). Central nervous system (CNS) stimulants are the primary pharmacological therapy used in treatment; however, these stimulant drugs carry a high potential for abuse and severe psychological/physical dependence. Viloxazine, a non-stimulant medication without evidence of drug dependence, is a selective norepinephrine reuptake inhibitor that has historically been prescribed as an anti-depressant medication. The extended-release (ER) form was approved by the US Food and Drug Administration (FDA) in April 2021 for the treatment of ADHD in pediatric patients aged 6-17 years. Phase 2 and 3 randomized control trials have demonstrated significant efficacy of viloxazine in improving ADHD symptoms versus placebo. Related to its long-standing use as an antidepressant, the safety profile and pharmacokinetics of viloxazine are well understood. Viloxazine appears to be a suitable alternative to current standard-of-care pharmacotherapy for ADHD, but the further investigation remains to be done in comparing its efficacy to that of current treatments.

Guanfacine Extended Release: A New Pharmacological Treatment Option in Europe

Children/adolescents with attention-deficit/hyperactivity disorder (ADHD) may have a poor or inadequate response to psychostimulants or be unable to tolerate their side-effects; furthermore, stimulants may be inappropriate because of co-existing conditions. Only one non-stimulant ADHD pharmacotherapy, the noradrenaline transporter inhibitor atomoxetine, is currently approved for use in Europe. We review recent advances in understanding of the pathophysiology of ADHD with a focus on the roles of catecholamine receptors in context of the α2A-adrenergic receptor agonist guanfacine extended release (GXR), a new non-stimulant treatment option in Europe. Neuroimaging studies of children/adolescents with ADHD show impaired brain maturation, and structural and functional anomalies in brain regions and networks. Neurobiological studies in ADHD and medication response patterns support involvement of monoaminergic neurotransmitters (primarily dopamine and noradrenaline). Guanfacine is a selective α2A-adrenergic receptor agonist that has been shown to improve prefrontal cortical cognitive function, including working memory. The hypothesized mode of action of guanfacine centres on direct stimulation of post-synaptic α2A-adrenergic receptors to enhance noradrenaline neurotransmission. Preclinical data suggest that guanfacine also influences dendritic spine growth and maturation. Clinical trials have demonstrated the efficacy of GXR in ADHD, and it is approved as monotherapy or adjunctive therapy to stimulants in Canada and the USA (for children and adolescents). GXR was approved recently in Europe for the treatment of ADHD in children and adolescents for whom stimulants are not suitable, not tolerated or have been shown to be ineffective. GXR may provide particular benefit for children/adolescents who have specific co-morbidities such as chronic tic disorders or oppositional defiant disorder (or oppositional symptoms) that have failed to respond to first-line treatment options.

Impact of Attention-Deficit Hyperactivity Disorder on School Performance: What are the Effects of Medication?

Attention-deficit hyperactivity disorder (ADHD) affects an estimated 5-7 % of schoolchildren worldwide. School functioning and academic achievement are frequently impaired by ADHD and represent one of the main reasons children start ADHD medication. Multiple potential causal pathways exist between ADHD and impaired school performance. In this review, we decompose school performance into three components and assess the impact of ADHD and its treatments on academic performance (assessed by grade point average [GPA], time on-task, percentage of work completed as well as percent completed correctly), academic skills (as measured by achievement tests and cognitive measures), and academic enablers (such as study skills, motivation, engagement, classroom behavior and interpersonal skills). Most studies examined only the short-term effects of medication on school performance. In these, ADHD medications have been observed to improve some aspects of school performance, with the largest impact on measures of academic performance such as seatwork productivity and on-task performance. In a subset of children, these benefits may translate into detectable improvements in GPA and achievement testing. However, limited data exists to support whether these changes are sustained over years. Optimizing medication effects requires periodic reassessment of school performance, necessitating a collaborative effort involving patients, parents, school staff and prescribers. Even with systematic reassessment, behavioral-based treatments and additional school-based services may be needed to maximize academic performance for the many youth with ADHD and prominent impairments in school performance.

Toward quality care in ADHD: defining the goals of treatment

OBJECTIVE

Therapeutic goals for chronic mental disorders like major depressive disorder (MDD) and schizophrenia have evolved in parallel with the growing medical knowledge about the course and treatment of these disorders. Although the knowledge base regarding the clinical course of ADHD, a chronic psychiatric disorder, has evolved beyond symptomatic improvement and short-term treatment response, long-term goals, such as functional remission, have not yet been clearly defined.

METHOD

A PubMed literature search was conducted to investigate the therapeutic goals of pharmacologic treatment referenced in the published literature from January 1998 through February 2010 using the following commonly used ADHD treatments as keywords: amphetamine, methylphenidate, atomoxetine, lisdexamfetamine, guanfacine, and clonidine. This search was then combined with an additional search that included the following outcome keywords: remission, relapse, remit, response, normal, normalization, recovery, and effectiveness.

RESULTS

Our search identified 102 publications. The majority (88.2% [90/102]) of these contained predefined criteria for treatment response. Predefined criteria for normalization and remission and/or relapse were presented in 4.9% (5/102), 12.7% (13/102), and 3.9% (4/102) of publications, respectively. There was a lack of consistency between the instruments used to measure outcomes as well as the criteria used to define treatment response, normalization, and remission as well as relapse.

CONCLUSION

The therapeutic goals in treating ADHD should address optimal treatment outcomes that go beyond modest reductions of ADHD symptoms to include syndromatic, symptomatic, and functional remission. Future work should focus on reliable and valid tools to measure these outcomes in the clinical trial setting.

Psychostimulants and cognition: a continuum of behavioral and cognitive activation

Psychostimulants such as cocaine have been used as performance enhancers throughout recorded history. Although psychostimulants are commonly prescribed to improve attention and cognition, a great deal of literature has described their ability to induce cognitive deficits, as well as addiction. How can a single drug class be known to produce both cognitive enhancement and impairment? Properties of the particular stimulant drug itself and individual differences between users have both been suggested to dictate the outcome of stimulant use. A more parsimonious alternative, which we endorse, is that dose is the critical determining factor in cognitive effects of stimulant drugs. Herein, we review several popular stimulants (cocaine, amphetamine, methylphenidate, modafinil, and caffeine), outlining their history of use, mechanism of action, and use and abuse today. One common graphic depiction of the cognitive effects of psychostimulants is an inverted U-shaped dose-effect curve. Moderate arousal is beneficial to cognition, whereas too much activation leads to cognitive impairment. In parallel to this schematic, we propose a continuum of psychostimulant activation that covers the transition from one drug effect to another as stimulant intake is increased. Low doses of stimulants effect increased arousal, attention, and cognitive enhancement; moderate doses can lead to feelings of euphoria and power, as well as addiction and cognitive impairment; and very high doses lead to psychosis and circulatory collapse. This continuum helps account for the seemingly disparate effects of stimulant drugs, with the same drug being associated with cognitive enhancement and impairment.

Fast vs. slow switching from stimulants to atomoxetine in children and adolescents with attention-deficit/hyperactivity disorder

OBJECTIVE

To compare fast versus slow switching from stimulants to atomoxetine (ATX) in children and adolescents with attention-deficit/hyperactivity disorder (ADHD).

METHODS

This was a randomized, controlled, open-label study in 6-16-year-old ADHD patients, previously treated with stimulants and cross-titrated (fast switch, over 2 weeks, or slow switch, over 10 weeks) to ATX because of unsatisfactory response and/or adverse events. Study duration was 14 weeks with an ATX standard target dose of 1.2 mg/kg/day. Primary measure was the change from baseline in the investigator-rated ADHD-Rating Scale (ADHD-RS) at weeks 2 and 10. Secondary measures included Global Impression of Perceived Difficulties (GIPD) and Child Health and Illness Profile-Child Edition (CHIP-CE).

RESULTS

The majority of the 111 patients were male (83.8%, n=93) and mean (SD) age was 11.5 (2.38) years. Mean baseline ADHD-RS total score was 36.0 in the fast and 38.0 in the slow group. Adjusted mean change after 2 weeks was -8.1 (-10.1; -6.1) in the fast and -8.0 (-9.9;-6.0) in the slow group (p=0.927), and after 10 weeks -15.0 (-17.4;-12.6) and -14.3 (-16.7;-12.0), respectively, (p=0.692). GIPD scores did not show differences between groups. Significant differences at week 10 were found in the CHIP-CE achievement domain favoring slow (p=0.036) and the comfort domain favoring fast cross-titration (p=0.030). No significant differences were found for adverse events, and differences for systolic blood pressure (BP) and weight were not considered clinically relevant.

CONCLUSIONS

ADHD-RS and GIPD scores improved in both switching groups. No clinically relevant differences between fast and slow switching from stimulants to ATX were found.

Amphetamine-induced memory impairment in a discriminative avoidance task is state-dependent in mice

In both humans and laboratory animals, the reports of cognitive effects following acute amphetamine (Amph) administration are mixed and depend, for example, on the timing of administration (e.g. before or after task acquisition) and/or on the memory model used. Besides its cognitive effects, Amph produces other important behavioural effects, including alterations in anxiety and general activity, which could modify the subject's internal state, thereby facilitating state-dependent learning. Importantly, state-dependency has been linked to drug dependence in humans. This study evaluates the role of state-dependent learning in Amph-induced memory deficits in mice submitted to a discriminative avoidance task. Mice were given Amph (3 mg/kg) before training and/or before testing in the plus-maze discriminative avoidance task, an animal model that concomitantly evaluates learning, memory, anxiety-like behaviour and general activity. Pre-training Amph administration did not affect the ability to learn the discriminative task, but rather induced anxiogenic-like effects and a marked retention deficit in the test session. This memory impairment was completely absent when animals received Amph before both the training and the test sessions. Amph-induced memory impairment of a discriminative avoidance task is state-dependent, such that a response acquired in the 'Amph state' cannot be recalled in the normal state. The involvement of anxiety alterations in this 'Amph state' is discussed.

Safety methodology in pediatric psychopharmacology trials

In recent years, there has been an increase in pediatric clinical trials as the result of an identified need for greater research with this population. Given the potential risks, and the vulnerability of the population, there has also been an identified need for greater safety elicitation and monitoring in pediatric psychopharmacology trials, for example, through the use of a data and safety monitoring board (DSMB). However, research indicates that pediatric trials and psychiatric trials are less likely to use a DSMB. The rationale for the current study was to determine what safety methodologies have been reported in pediatric psychopharmacology trials over the past 10 years. A literature review was conducted of all pediatric psychopharmacology trials published since 2001. Results indicated that the most common elicitation method was collecting laboratory information and vital signs. Six percent of trials solely relied on spontaneous reporting of adverse events, and only 11.8% reported using a DSMB. These results suggest that elicitation methods and use of DSMBs are still low. Practical considerations, affected stakeholders, and barriers are discussed. Recommendations for moving forward include the use of multiple elicitation methods and automatic requirement of a DSMB for pediatric psychopharmacology trials, required completion of a standardized safety reporting form, and engaging multiple interested parties in these processes.

A long-term open-label safety and effectiveness trial of lisdexamfetamine dimesylate in adolescents with attention-deficit/hyperactivity disorder

OBJECTIVE

Information on psychostimulant treatment in long-term studies for attention-deficit/hyperactivity disorder (ADHD) in adolescents is limited. This study aimed to assess the safety and effectiveness of lisdexamfetamine dimesylate (LDX) over 52 weeks in adolescents with ADHD.

METHODS

This open-label multicenter study enrolled eligible participants after their participation in a randomized, double-blind, placebo-controlled 4 week trial in adolescents with ADHD. Following a 4 week dose-optimization phase, participants were maintained on treatment for up to ∼48 weeks on an optimal dose. Safety assessments included treatment-emergent adverse events (TEAEs), vital signs, laboratory findings, and electrocardiograms. Effectiveness measures included the ADHD Rating Scale IV (ADHD-RS-IV; primary) and Clinical Global Impressions-Improvement (CGI-I). The Youth Quality of Life-Research Version (YQOL-R) was also included in this study; raw scores are transformed to a 0-100 point scale.

RESULTS

Of 269 enrolled (from the antecedent study), 265 (98.5%) were in the safety population and effectiveness population. Common TEAEs (≥5%) with LDX included upper respiratory tract infection (21.9%), decreased appetite (21.1%), headache (20.8%), decreased weight (16.2%), irritability (12.5%), insomnia (12.1%), nasopharyngitis (7.2%), influenza (6.8%), dizziness (5.3%), and dry mouth (5.3%). At end point, for all LDX doses in the overall safety population, mean (SD) increase from baseline in systolic blood pressure was 2.3 (10.53) mm Hg, diastolic blood pressure was 2.5 (8.37) mm Hg, and pulse rate was 6.3 (12.74) bpm. No clinically meaningful electrocardiogram or vital sign changes were observed. At end point with LDX treatment, the ADHD-RS-IV mean (SD) total score change from antecedent study baseline was -26.2 (9.75) (p<0.001); 87.2% of participants were improved (CGI-I=1 or 2). Baseline (antecedent study) mean (SD) YQOL-R perceptual total score was 79.8 (11.28) and increased by 3.9 (9.73) at end point (p<0.001).

CONCLUSIONS

LDX demonstrated a long-term safety profile similar to that of other long-acting psychostimulants and was effective, as indicated by improvements in ADHD symptoms and participant-perceived YQOL, in adolescents with ADHD.

CLINICAL TRIAL REGISTRATION

NCT00764868, http://www.clinicaltrials.gov/ct2/show/NCT00764868?term=SPD489-306&rank=1.

[The medical treatment of attention deficit hyperactivity disorder (ADHD) with amphetamines in children and adolescents]

INTRODUCTION

Psychostimulants (methylphenidate and amphetamines) are the drugs of first choice in the pharmacological treatment of children and adolescents with attention deficit hyperactivity disorder (ADHD).

OBJECTIVE

We summarize the pharmacological characteristics of amphetamines and compare them with methylphenidate, special emphasis being given to a comparison of effects and side effects of the two substances. Finally, we analyze the abuse and addiction risks.

METHODS

Publications were chosen based on a Medline analysis for controlled studies and meta-analyses published between 1980 and 2011; keywords were amphetamine, amphetamine salts, lisdexamphetamine, controlled studies, and metaanalyses.

RESULTS AND DISCUSSION

Amphetamines generally exhibit some pharmacologic similarities with methylphenidate. However, besides inhibiting dopamine reuptake amphetamines also cause the release of monoamines. Moreover, plasma half-life is significantly prolonged. The clinical efficacy and tolerability of amphetamines is comparable to methylphenidate. Amphetamines can therefore be used if the individual response to methylphenidate or tolerability is insufficient before switching to a nonstimulant substance, thus improving the total response rate to psychostimulant treatment. Because of the high abuse potential of amphetamines, especially in adults, the prodrug lisdexamphetamine (Vyvanse) could become an effective treatment alternative. Available study data suggest a combination of high clinical effect size with a beneficial pharmacokinetic profile and a reduced abuse risk.

CONCLUSIONS

In addition to methylphenidate, amphetamines serve as important complements in the psychostimulant treatment of ADHD. Future studies should focus on a differential comparison of the two substances with regard to their effects on different core symptom constellations and the presence of various comorbidities.

The pharmacology and clinical outcomes of amphetamines to treat ADHD: does composition matter?

Attention-deficit hyperactivity disorder (ADHD) treatment options include pharmacological and nonpharmacological approaches. In North America, psychostimulants (amphetamine and methylphenidate) are considered first-line pharmacological treatments for patients (children, adolescents and adults) with ADHD. However, in the UK, National Institute for Health and Clinical Excellence (NICE) guidelines have placed short-acting d-amphetamine as a third-line treatment option due to a lack of contemporary, published clinical trials on its efficacy and the concerns from clinical and patient experts regarding the potential for increased abuse and/or misuse compared with methylphenidate. These guidelines do not account for some of the more recent amphetamine products that have been developed to alleviate some of these concerns, but that are not currently approved in the UK or other European countries. The purpose of this review is to describe the pharmacology and clinical efficacy of various amphetamine compositions, as well as to explore the apparent differences in these compositions and their associated risks and benefits. A PubMed literature search was conducted to investigate amphetamine pharmacology, clinical efficacy and safety and ADHD outcomes in the published literature from 1980 through March 2011. Search terms included the keywords 'ADHD' or 'ADD' or 'hyperkinetic disorder' and any of the following keywords combined with 'or': 'amphetamine', 'dexamphetamine', 'mixed amphetamine salts', 'lisdexamfetamine' and 'methamphetamine'. The search included English-language primary research articles and review articles but excluded editorial articles and commentaries. The literature search resulted in 330 articles. Pertinent articles relating to amphetamine pharmacology, compositions, clinical efficacy and safety, effectiveness and tolerability, ADHD outcomes and abuse liability were included in this review. The different delivery profiles of amphetamine compositions result in pharmacological and pharmacokinetic differences that contribute to varying effects in the clinical treatment of ADHD, ADHD outcomes and abuse liability. The efficacy and safety of amphetamine compositions for the treatment of ADHD have been demonstrated in clinical trials and meta-analyses, and the long-acting amphetamine compositions have been widely studied and found efficacious without increased adverse effects. Long-acting amphetamine compositions offer the obvious advantage of enhanced duration of action over short-acting amphetamine compositions, and lisdexamfetamine has been shown to have reduced abuse liability compared with short-acting amphetamine.

A controlled trial of extended-release guanfacine and psychostimulants for attention-deficit/hyperactivity disorder

OBJECTIVE

To examine efficacy, tolerability, and safety of guanfacine extended release (GXR; ≤4 mg/d) adjunctive to a long-acting psychostimulant for the treatment of attention-deficit/hyperactivity disorder (ADHD) in children and adolescents 6 to 17 years of age with suboptimal, but partial, response to psychostimulant alone.

METHOD

In this multicenter, 9-week, double-blind, placebo-controlled, dose-optimization study, subjects (N = 461) continued their stable dose of psychostimulant given in the morning and were randomized to receive GXR in the morning (GXR AM), GXR in the evening (GXR PM), or placebo. Efficacy measures included 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 (AEs), vital signs, electrocardiograms, and laboratory evaluations.

RESULTS

At endpoint, GXR treatment groups showed significantly greater improvement from baseline ADHD-RS-IV total scores compared with placebo plus psychostimulant (GXR AM, p = .002; GXR PM, p < .001). Significant benefits of GXR treatment versus placebo plus psychostimulant were observed on the CGI-S (GXR AM, p = .013; GXR PM, p < .001) and CGI-I (GXR AM, p = .024; GXR PM, p = .003). At endpoint, small mean decreases in pulse, systolic, and diastolic blood pressure were observed in GXR treatment groups versus placebo plus psychostimulant. No new safety signals emerged following administration of GXR with psychostimulants versus psychostimulants alone. Most AEs were mild to moderate in severity.

CONCLUSIONS

Morning or evening GXR administered adjunctively to a psychostimulant showed significantly greater improvement over placebo plus psychostimulant in ADHD symptoms and generated no new safety signals. Clinical trial registration information-Efficacy and Safety of SPD503 in Combination With Psychostimulants; http://www.clinicaltrials.gov; NCT00734578.

Development of an LC-MS/MS method for the analysis of serotonin and related compounds in urine and the identification of a potential biomarker for attention deficit hyperactivity/hyperkinetic disorder

Serotonin is a major neurotransmitter and affects various functions both in the brain and in the rest of the body. It has been demonstrated that altered serotinergic function is implicated in various psychiatric disorders including depression and schizophrenia. Serotonin has also been implicated along with dopamine in attention deficit-hyperkinetic disorder (AD-HKD). This study provides a versatile validated method for the analysis of serotonin, hydroxyindole acetic acid and dopamine in urine using LC-MS/MS. This method was then used to quantify these analytes in a test group of 17 children diagnosed with severe AD-HKD. This group was compared to a matched control group to investigate the possibility that one of these compounds may be a potential biomarker for this condition. The developed method provided good linear calibration curves for the multiplex assay of analytes in urine (0.05-3.27 nmol/L; R(2) ≥ 0.9977). Acceptable inter-day repeatability was achieved for all analytes with RSD values (n = 9) ranging from 1.1% to 9.3% over a concentration range of 0.11-3.27 μmol/L in urine. Excellent limits of detection (LOD) and limits of quantitation (LOQ) were achieved with LODs of 8.8-18.2 nmol/L and the LOQs of 29.4-55.7 nmol/L for analytes in urine. Recoveries were in the ranges of 98-104%, 100-106% and 91-107% for serotonin, 5-HIAA and dopamine, respectively. An appropriate sample clean-up procedure for urine was developed to ensure efficient recovery and reproducibility on analysis. Evaluation of matrix effects was also carried out and the influence of ion suppression on analytical results reported. Confirmatory analysis was carried out on a linear trap quadrupole-Orbitrap mass spectrometer to obtain high mass accuracy data of the target analytes in the clinical samples.

Age-grouped differences in adverse drug events from psychotropic medication

OBJECTIVE

This review aims to detail specific psychotropic medication treatment differences in adverse drug events (ADEs) between children, adolescents, and adults.

METHOD

A thorough data-based search of ADEs was made, augmented by findings from approved and updated U.S. Food and Drug Administration (FDA) drug labels, controlled clinical trial reports, and from FDA information on ADEs at scheduled public hearings.

RESULTS

Children were found to generally exhibit more ADEs to psychotropic medication than adolescents and adults. These ADEs primarily include altered growth velocity, rash, vomiting, dystonia, tics, affect lability, activation, metabolic blood test abnormalities, sedation, sialorrhea, and electrocardiogram irregularities.

CONCLUSION

Children have more biological vulnerabilities than older individuals, which could account for their greater rate of ADEs to psychotropic medication treatment.

Efficacy and safety of lisdexamfetamine dimesylate in adolescents with attention-deficit/hyperactivity disorder

OBJECTIVE

To examine lisdexamfetamine dimesylate (LDX) efficacy and safety versus placebo in adolescents with attention-deficit/hyperactivity disorder (ADHD).

METHOD

Adolescents (13 through 17) with at least moderately symptomatic ADHD (ADHD Rating Scale IV: Clinician Version [ADHD-RS-IV] score ≥28) were randomized to placebo or LDX (30, 50, or 70 mg/d) in a 4-week, forced-dose titration, double-blind study. Primary and secondary efficacy measures were the ADHD-RS-IV, Clinical Global Impressions-Improvement (CGI-I), and Youth QOL-Research Version (YQOL-R). Safety assessments included treatment-emergent adverse events (TEAEs), vital signs, laboratory findings, physical examinations, and ECG.

RESULTS

Overall, 314 participants were randomized; 309 were in efficacy analyses and 49 withdrew (11 due to TEAEs). Least squares mean (SE) change from baseline at endpoint in ADHD-RS-IV total scores were -18.3 (1.25), -21.1 (1.28), -20.7 (1.25) for 30, 50, and 70 mg/d LDX, respectively; -12.8 (1.25) for placebo (p ≤ .0056 versus placebo for each). Differences in ADHD-RS-IV total scores favored all LDX doses versus placebo at all weeks (p ≤ .0076). On the CGI-I, 69.1% of participants were rated very much/much improved at endpoint with LDX all doses versus placebo (39.5%) (p < .0001). YQOL-R changes at endpoint scores for LDX groups versus placebo were not significant. Commonly reported LDX (all doses combined) TEAEs (≥5%) were decreased appetite, headache, insomnia, decreased weight, and irritability. Small mean increases in pulse and blood pressure and no clinically meaningful trends in ECG changes were noted with LDX.

CONCLUSIONS

LDX at all doses was effective versus placebo in treating adolescent ADHD and demonstrated a safety profile consistent with previous LDX studies. CLINICAL TRIALS REGISTRY INFORMATION: Efficacy and Safety of Lisdexamfetamine Dimesylate (LDX) in Adolescents With Attention-Deficit/Hyperactivity Disorder (ADHD); http://www.clinicaltrials.gov; NCT00735371.

Changes in emotions related to medication used to treat ADHD. Part I: literature review

OBJECTIVE

To summarize the literature investigating changes in emotional expression (EE) as a function of pharmacotherapy in the treatment of ADHD and to differentiate emotional effects related to ADHD pharmacotherapy from emotional effects related to ADHD as a disorder.

METHOD

English language articles published from January 1, 1988, through August 31, 2008 were identified through a PubMed literature search using the search terms attention, ADHD, hyperactive, hyperkinesis, and ADD cross-referenced with medication terms amphetamine, lisdexamfetamine, methylphenidate , guanfacine, atomoxetine, and clonidine. The search was limited to randomized, controlled trials. Abstracts from all identified articles were selected for further review if they met criteria including (a) presence of a placebo arm, (b) children ≤ 18 years of age, (c) ≥ 20 participants, and (b) study design elements that would allow reviewers to determine whether EE phenomena were specifically attributable to medication effects versus alternative explanations (e.g., time, maturation, baseline comorbidity, selection artifacts, or treatments other than the medication-placebo contrast). Qualifying full-text articles were reviewed for prespecified EE terms.

RESULTS

Of 148 articles that met selection criteria, 47 reported varying types of EE. Eight of these included two active treatment arms. Hence, 55 data sets were identified. Patterns of change in EE in studies meeting search criteria are discussed. Data sets that reported accounts of EE by the percentage of patients were compiled and further analyzed for specific medication classes. The changes in EE are further discussed as (a) salutary or detrimental, (b) associated with time of day or circumscribed, and (c) presumed to be caused by pharmacological effects.

CONCLUSIONS

Definitive methodologies for assessing the presence of changes in EE in clinical trials and guidelines for the evaluation of EE in clinical practice are yet to be established and are needed. Such guidelines could be used by clinicians to monitor positive and negative changes in emotion when patients are taking medications for their ADHD.

Amphetamine and extinction of cued fear

Much research is focused on developing novel drugs to improve memory. In particular, psychostimulants have been shown to enhance memory and have a long history of safe use in humans. In prior work, we have shown that very low doses of amphetamine administered before training on a Pavlovian fear-conditioning task can dramatically facilitate the acquisition of cued fear. The current experiment sought to expand these findings to the extinction of cued fear, a well-known paradigm with therapeutic implications for learned phobias and post-traumatic stress disorder. If extinction reflects new learning, one might expect drugs that enhance the acquisition of cued fear to also enhance the extinction of cued fear. This experiment examined whether 0.005 or 0.05 mg/kg of D-amphetamine (therapeutic doses shown to enhance acquisition) also enhance the extinction of cued fear. Contrary to our hypothesis, amphetamine did not accelerate extinction. Thus, at doses that enhance acquisition of conditioned fear, amphetamine does not appear to enhance extinction.

Gene expression of synaptosomal-associated protein 25 (SNAP-25) in the prefrontal cortex of the spontaneously hypertensive rat (SHR)

Dopamine is believed to play an important role in the etiology of attention-deficit/hyperactivity disorder (ADHD). In our previous study, we showed that gene expression of dopamine D4 receptor decreased in the spontaneously hypertensive rat (SHR) in the prefrontal cortex (PFC). In the present study, we explored the potential causes of dysfunction in the dopamine system in ADHD. It is the first time that neuronal activities in both juvenile SHR and WKY rats have been measured by functional MRI (fMRI). Our results showed that in PFC the Blood Oxygenation Level Dependent (BOLD) signal response in SHR was much higher than WKY under stressful situations. We tested the effects of acute and repeated administration of amphetamine on behavioral changes in SHR combined with the expression of the neuronal activity marker, c-fos, in the PFC. Meanwhile dopamine-related gene expression was measured in the PFC after repeated administration of amphetamine. We found that potential neuronal damage occurred through deficit of D2-like receptor protective functions in the PFC of the SHR. We also measured the expression of synaptosomal-associated protein 25 (SNAP-25) in SHR in PFC. The results showed decreased expression of SNAP-25 mRNA in the PFC of SHR; this defect disappeared after repeated injection of D-AMP.

Memory and psychostimulants: modulation of Pavlovian fear conditioning by amphetamine in C57BL/6 mice

RATIONALE AND OBJECTIVES

With the use of prescription stimulants on the rise, it is important to examine the cognitive effects of low and moderate doses of stimulants rather than only those typical of addicts.

MATERIALS AND METHODS

The present study examined the effects a range of doses (0.005-8 mg/kg) of D: -amphetamine sulfate on cued and contextual Pavlovian fear conditioning in mice.

RESULTS

In agreement with previous research, subjects administered with a moderately high dose of amphetamine (8 mg/kg) pre-training, typical of what addicts might take, displayed impaired conditioned freezing when tested off-drug. Alternately, subjects injected with a very low dose of amphetamine (0.005, 0.025, or 0.05 mg/kg) pre-training, similar to the therapeutic doses for attention deficit hyperactivity disorder, displayed enhanced memory when tested off-drug. A control study showed that these effects were not due to state-dependent learning.

CONCLUSIONS

Thus, dose is a critical determinant of the cognitive effects of psychostimulants.

Nicotine and amphetamine acutely cross-potentiate their behavioral and neurochemical responses in female Holtzman rats

RATIONALE

Psychostimulants are often used in close temporal proximity to nicotine and have been reported to enhance acutely nicotine's desirability in humans.

OBJECTIVE

To investigate the acute associations between amphetamine and nicotine, we examined the potentiative interactions between clinically relevant, low doses of these drugs on locomotor activity, and dopamine overflow in the rat.

MATERIALS AND METHODS

Locomotor activity was measured by telemetry in the home cage environment, and dopamine overflow was evaluated in striatal slice preparations from female Holtzman rats.

RESULTS

When administered simultaneously, nicotine and amphetamine produced a predominantly additive effect on locomotor behavior. However amphetamine, when given 2-4 h before nicotine, strongly potentiated nicotine-induced locomotor activity. Correspondingly, nicotine given 1-4 h before amphetamine robustly enhanced amphetamine-stimulated locomotor activity even when the effects of the nicotine pretreatment dissipated. Acute nicotine pretreatment similarly potentiated the effects of dopamine transporter ligands, cocaine, nomifensine, and methamphetamine but not a direct dopamine receptor agonist. Consistent with the behavioral studies, in vivo nicotine pretreatment exaggerated amphetamine-induced dopamine efflux from rat striatal slices. Likewise, in vivo pretreatment of rats with amphetamine potentiated nicotine-induced dopamine efflux from striatal slices. Direct pretreatment of striatal tissue by nicotine also potentiated subsequent amphetamine-stimulated dopamine overflow, further suggesting that the nicotine-amphetamine interaction occurs at the level of the dopamine terminal.

CONCLUSION

Overall, the present data demonstrate that acute interactions of nicotine and other psychomotor stimulants produce potentiative effects and that these transient interactions may play a role in the frequent co-use and abuse of nicotine and other stimulants.

Transition from methylphenidate or amphetamine to atomoxetine in children and adolescents with attention-deficit/hyperactivity disorder--a preliminary tolerability and efficacy study

BACKGROUND

The primary treatment for attention-deficit/hyperactivity disorder (ADHD) has been psychostimulants. Recently developed nonpsychostimulant treatments have allowed certain patients to switch from a psychostimulant to a nonpsychostimulant. However, the outcomes of such switches have not been systematically studied.

OBJECTIVE

The purpose of this pilot study was to assess treatment tolerance and efficacy during a cross-taper transition from methylphenidate or amphetamine to atomoxetine among children and adolescents with ADHD.

METHODS

This pilot study was conducted in patients (aged 6-17 years) with incomplete responses (failure to obtain full reduction/elimination of symptoms) or intolerance of adverse events (AEs) during psychostimulant treatment. Patients continued ongoing psychostimulant treatment during the first week of the study. Transition to atomoxetine began by administering atomoxetine 0.5 mg/kg . d plus full-dose psychostimulant for 1 week, followed in the second week by 1.2 mg/kg . d atomoxetine plus half-dose psychostimulant. Patients remained on 1.2 mg/kg . d atomoxetine monotherapy for the remaining 5 weeks. This stepwise transition was enacted due to the difference in pharmacodynamics between the psychostimulants and atomoxetine. Applying a stepwise cross-titration allowed for better control of ADHD symptoms during the intervening period. Change in ADHD symptoms, as measured by the mean change in the Attention-Deficit/Hyperactivity Disorder Rating Scale-IV-Parent Version: Investigator-administered and -scored (ADHDRS-IV-Parent:Inv), was assessed from baseline to end point.

RESULTS

Of the 62 subjects enrolled in the study, 39 (62.9%) were diagnosed as ADHD-combined type. Similar proportions were receiving methylphenidate (51.6%) and amphetamine (48.4%). Slightly more wished to switch due to inadequate response (53.2%) than intolerability (46.8%). Nine subjects discontinued at various times during the course of the study (patient or parent/caregiver decision [4], AE [2], protocol violation [2], and lack of efficacy [1]). Mean (SD) ADHDRS-IV-Parent:Inv total scores (n = 59, last-observation-carried-forward) improved significantly from baseline (visit 2) to an end point (32.1 [10.5] vs 22.6 [14.0]; P < 0.001). Of the 58 subjects answering in the atomoxetine monotherapy phase, 38 (65.5%) reported a preference for atomoxetine treatment over their previous psychostimulant. Tolerability results were as follows: 26 (44.1%) of 59 patients reported >or=1 AE, the most common being somnolence (4 [6.8%]), fatigue (3 [5.1%]), decreased appetite (3 [5.1%]), cough (3 [5.1%]), headache (3 [5.1%]), and contact dermatitis (2 [3.4%]). No clinically severe AEs were reported. Both mean (SD) diastolic (2.4 [7.8] mm Hg; P = 0.031) and systolic (2.4 [7.9] mm Hg; P = 0.029) blood pressures increased significantly from baseline to end point. Electrocardiography revealed a significant increase in mean (SD) heart rate (9.2 [11.6] bpm; P < 0.001) and a corresponding decrease in mean (SD) RR interval (-77.8 [98.2] ms; P < 0.001). Statistically significant, but mild, increases in diastolic pressure and heart rate were observed.

CONCLUSION

These children and adolescent patients were successfully switched from methylphenidate or amphetamine to atomoxetine treatment, with resulting improvement in ADHD symptom severity from baseline in this pilot study.

Remission versus response as the goal of therapy in ADHD: A new standard for the field?

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) has a substantial negative impact; however, within long-term follow-up studies, a proportion of patients do very well, both symptomatically and functionally, suggesting that the lower the symptom burden, the greater the functional improvements. Studies in major depressive disorder have identified a relationship between symptomatic remission and restoration of normal functioning.

OBJECTIVE

The purpose of this article was to propose a definition of remission in ADHD, review remission rates in clinical trials for commonly used medications, and explore the relationship between symptomatic remission and optimal functioning.

METHODS

Remission and response rates for medications were obtained through MEDLINE searches of English-language citations (1999-2005) and meeting abstracts (2003-2005) using the terms amphetamine, atomoxetine, methylphenidate, ADHD, efficacy, effectiveness, and controlled trial, as well as hand searches of efficacy studies. Evidence from randomized controlled trials, as well as effectiveness studies, where the proportions of patients achieving predefined cutoff points for remission or response are reported, was reviewed. Because higher remission rates were identified with the oral, osmotic, controlled-release system (OROS) of methylphenidate, a relationship between symptomatic response/remission and optimal functioning was explored further.

RESULTS

Remission in ADHD should be defined as a loss of diagnostic status, minimal or no symptoms, and optimal functioning when individuals are being treated with or without medication. Symptomatic remission can be operationalized as a mean total score of S1 on most standardized questionnaires. For the medications examined (OROS methylphenidate, immediate-release methylphenidate, atomoxetine, and mixed amphetamine salts), response rates were comparable at approximately 70% to 75%; however, remission rates were higher with OROS methylphenidate compared with either immediate-release methylphenidate or atomoxetine (remission rates with amphetamines were not found). Benefits, including decreased illness burden as well as improved psychosocial and academic functioning, were associated with treatment versus no treatment and were greater with medication that offered higher remission rates.

CONCLUSIONS

The literature provided evidence that greater symptom improvements are associated with greater functional improvements, emphasizing that remission of ADHD as defined should be the goal of therapy. Treatment ought to include the early use of strategies with the greatest chance of achieving remission. Future clinical research should use remission as the primary outcome.

Combination pharmacotherapy for adult ADHD

Attention-deficit/hyperactivity disorder (ADHD) is one of the most prevalent neuropsychiatric disorders of adulthood. Although clinical guidelines recommend monotherapy with stimulants or atomoxetine, combination pharmacotherapy is a common practice among clinicians. There are four main situations in which combination medications may be necessary: partial response, dose-limiting side effects, associated disorders, and comorbid diagnoses. We present data from two chart reviews that support existing research on combination pharmacotherapy. Adjunct treatment of d-methylphenidate to stimulant medications extended the duration of therapeutic effect. Adjunct treatment of mirtazapine to stimulant medications reduced associated insomnia. These data support previous research that validates the use of combination pharmacotherapy for adults with ADHD.

Pharmacotherapy of attention-deficit hyperactivity disorder in children and adolescents: update on new stimulant preparations, atomoxetine, and novel treatments

This article reviews data on the safety, tolerability, and efficacy of the extended-delivery stimulant preparations and atomoxetine, including nine methylphenidate formulations, five amphetamine formulations, and one norepinephrine reuptake inhibitor, now indicated for treatment of attention-deficit hyperactivity disorder (ADHD). Six of the nine methylphenidate formulations, three of the five compounds, and the norepinephrine reuptake inhibitor are long-acting, potentially once-daily agents. Data on treatment of common adverse events are described, and data on investigational treatments of ADHD are reviewed.

The safety of non-stimulant agents for the treatment of attention-deficit hyperactivity disorder

Due to their well-established efficacy and safety, stimulants are the drugs of first choice if medication for attention-deficit hyperactivity disorder (ADHD) is required. Nevertheless, for some individuals other, non-stimulant treatments are needed for several reasons. If so, atomoxetine is recommended as a second-line treatment. In addition, several tricyclic antidepressants, such as desipramine or imipramine, as well as alpha-2 agonists, especially clonidine or bupropion, might be efficient in treating ADHD, in particular in specific co-morbid conditions. Despite the fact that non-stimulant treatments in ADHD are usually well-tolerated with side effects being mostly moderate and transient, special safety aspects and precautions, specific for each drug, have to be considered whenever a non-stimulant treatment is chosen. This review focuses on the tolerability, occurrence of adverse events, precautions required to prevent severe adverse events, and essential pharmacological interaction in the treatment of ADHD symptoms by non-stimulants.

Die Wirksamkeit von Stimulanzien-Retardpräparaten bei Kindern und Jugendlichen mit ADHD - eine systematische Übersicht

Zusammenfassung: Stimulanzien sind das Mittel der Wahl zur pharmakologischen Behandlung einer Aufmerksamkeits-/Hyperaktivitätsstörung. Jedoch ist die Wirkdauer von schnell freisetzenden Präparaten oft nicht ausreichend. Mittlerweile wurden verschiedene retardierte Methylphenidat-, aber auch Amphetaminformen entwickelt, um die Probleme einer mehrfach täglichen Einnahme zu minimieren. Der Artikel stellt die klinischen Studien zu Wirksamkeit, Wirkdauer und Nebenwirkungsprofil verschiedener Stimulanzienformen dar. In der klinischen Anwendung sind die neuen Retard-Produkte wirkungsvolle Alternativen. Eine kontinuierliche mehrstufige Freisetzung des Wirkstoffs über den Tag verteilt nach einmaliger Medikamentengabe bietet Vorteile. Allerdings müssen Nebenwirkungen durch die verlängerte Wirkungsdauer genau beobachtet werden. Eine genauere Anpassung an die jeweiligen Erfordernisse der verschiedenen Tagesabschnitte und -bedürfnisse der Kinder und Jugendlichen ist schwierig. Die Erprobung von Titrierungsschemata unter Einbeziehung von schnell und verzögert freisetzenden Präparaten bleibt eine Aufgabe zukünftiger Forschung.

SLI381 (Adderall XR), a two-component, extended-release formulation of mixed amphetamine salts: bioavailability of three test formulations and comparison of fasted, fed, and sprinkled administration

STUDY OBJECTIVES

To assess the bioavailability of three test formulations of a single dose of extended-release Adderall 20-mg capsules compared with two doses of immediate-release Adderall 10-mg tablets, and to assess the bioequivalence of a single 30-mg dose of the chosen extended-release Adderall formulation (designated as SLI381) administered in applesauce (sprinkled) and the same dose administered as an intact capsule with or without food.

DESIGN

Randomized, open-label, crossover study.

SETTING

Clinical research unit.

PATIENTS

Forty-one healthy adults.

INTERVENTIONS

Study A had four treatment sequences: three test formulations (A, B, and C) of a single dose of extended-release Adderall 20 mg, and two 10-mg doses of Adderall given 4 hours apart. Study B had three treatment sequences: a single dose of SLI381 30 mg as an intact capsule after overnight fast, an intact capsule after a high-fat breakfast, and the contents of a capsule sprinkled in 1 tablespoon of applesauce.

MEASUREMENTS AND MAIN RESULTS

The 20-mg test formulation A had comparable pharmacokinetic profiles and bioequivalence in rate and extent of drug absorption to Adderall 10 mg twice/day for both d- and l-amphetamine. Formulations B and C had statistically significant differences from the reference drug in some pharmacokinetic parameters. A 30-mg dose of SLI381 showed no significant differences in rate and extent of absorption of d- and l-amphetamine for fasted or sprinkled conditions compared with the high-fat meal condition.

CONCLUSION

SLI381 20 mg/day is bioequivalent to Adderall 10 mg twice/day. SLI381 30 mg administered in applesauce is bioequivalent in terms of both rate and extent of absorption to the same dose administered as an intact capsule in both fasted and fed states.

Efficacy of Adderall for Attention-Deficit/Hyperactivity Disorder: a meta-analysis

Stimulant medication has, for many years, been the pharmacological treatment of choice for children and adults with Attention-Deficit/Hyperactivity Disorder (ADHD). Several studies have shown Adderall , to be efficacious for measures of inattention, hyperactivity-impulsivity, aggression, disruptive behavior, and academic productivity. Although these studies provide useful information for clinicians treating ADHD children and adults, the variability in efficacy among the different types of measures used within each study has not been comprehensively examined. Thus, to provide a clearer picture of what conclusions can be drawn from these studies, we performed a meta-analysis. Data from the six available studies of standard release Adderall show it to be efficacious for symptoms of inattention, hyperactivity-impulsivity, and aggression, as well as global ratings. Its efficacy was significant for clinician, parent, and teacher ratings, and for both fixed- and best-dose designs.

A randomized, double-blind, placebo-controlled, parallel-group study of SLI381 (Adderall XR) in children with attention-deficit/hyperactivity disorder

OBJECTIVE

SLI381 (Adderall XR) is a 2-component extended-release capsule formulation of Adderall designed to produce a therapeutic effect that lasts throughout the day with 1 morning dose. The primary objective of this study was to assess the efficacy and safety of SLI381 compared with placebo in the treatment of attention-deficit/hyperactivity disorder (ADHD) in children in a naturalistic school and home setting. A secondary objective was to assess the diurnal variation in responses based on morning and afternoon assessments.

METHODS

A multicenter, randomized, double-blind, parallel-group, placebo-controlled trial was conducted at 47 sites. After a 1-week washout of any previous stimulant medication, patients were randomized to receive single-daily morning doses of placebo or SLI381 10 mg, 20 mg, or 30 mg for 3 weeks. Participants aged 6 to 12 years inclusive who satisfied Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria diagnosis of ADHD were included. The primary efficacy parameter was the Conners Global Index Scale for Teachers. Secondary efficacy parameters included the Conners Global Index Scale for Parents, the Clinical Global Impressions Scale for improvement, and the Parent Global Assessment for improvement. Safety was assessed by recording adverse events, laboratory tests, and vital signs at each visit during the study. Physical examinations and electrocardiograms were performed at the screening and the end of the study.

RESULTS

Five hundred eighty-four children were randomized, 563 were included in the intent-to-treat population, and 509 completed the entire study. Intention-to-treat analysis of Conners Global Index Scale for Teachers and Conners Global Index Scale for Parents scores revealed significant improvement in morning, afternoon, and late afternoon behavior for all active treatment groups versus placebo. All active treatment groups showed significant dose-related improvement in behavior from baseline. Both the Clinical Global Impressions Scale for improvement and Parent Global Assessment for improvement showed all doses of SLI381 to be superior to placebo at treatment end and both confirmed the dose-response relationship between improvement and the SLI381 dose. The incidence of spontaneously reported adverse events was low and similar for active treatments and placebo.

CONCLUSIONS

SLI381 produced consistent, dose-related improvements on all measures of efficacy. The extended-release nature of the SLI381 formulation was shown by continued, significant improvement in afternoon assessments by teachers and afternoon and late afternoon assessments by parents. The time course and therapeutic effects of SLI381 suggests that this medication is an efficacious once-daily treatment for children with ADHD.

The Diagnosis and Management of Attention-Deficit/Hyperactivity Disorder in Pediatric Patients

Attention-deficit/hyperactivity disorder (ADHD), characterized by developmentally inappropriate inattentiveness, impulsivity, and hyperactivity, is the most common and thoroughly researched neuropsychiatric disorder affecting children and adolescents. The diagnosis of ADHD requires a comprehensive clinical assessment including a detailed patient history, clinical interview and observation, and a thorough physical examination. A variety of other disorders can masquerade as ADHD or coexist with the disorder. The clinician must recognize environmental influences that may affect the severity of symptoms exhibited in the child or adolescent with ADHD. Clinically, treatment with a stimulant can be expected to result in an immediate, often dramatic, improvement in the core symptoms of ADHD. Studies published over the past 20 years indicate that the symptoms of ADHD, which were originally thought to diminish as a child matured, may persist into adolescence and adulthood. This article is a review of the most recent recommendations and clinical data regarding the diagnosis and management of ADHD in children and adolescents to assist with appropriate and prudent clinical decision making.