Safety, efficacy and extended duration of action of mixed amphetamine salts extended-release capsules for the treatment of ADHD

Deficiency in Re-Orienting of Attention in Adults with Attention-Deficit Hyperactivity Disorder

Objective: To characterize potential brain indexes of attention deficit hyperactivity disorder (ADHD) in adults. Methods: In an effort to develop objective, laboratory-based tests that can help to establish ADHD diagnosis, the brain indexes of distractibility was investigated in a group of adults. We used event-related brain potentials (ERPs) and performance measures in a forced-choice visual task. Results: Behaviorally aberrant distractibility in the ADHD group was significantly higher. Across three ERP components of distraction: N1 enhancement, P300 (P3a), and Reorienting Negativity (RON) the significant difference between ADHD and matched controls was found in the amplitude of the RON. We used non-parametric randomization tests, enabling us to statistically validated this difference between-group. Conclusions: Our main results of this feasibility study suggest that among other ERP components associated with auditory distraction, the RON response is promising index for a potential biomarker of deficient re-orienting of attention in adults s with ADHD.

Adult Patient Preferences for Long-Acting ADHD Treatments: A Discrete Choice Experiment

BACKGROUND AND OBJECTIVE

Treatment for attention deficit hyperactivity disorder (ADHD) requires a multifaceted approach including psychosocial interventions and pharmacological treatment. This study evaluates preferences for specific attributes associated with different long-acting stimulant treatment among US adults with ADHD.

METHODS

Patients completed an online, cross-sectional survey, incorporating a discrete choice experiment to assess preferences for attributes.

RESULTS

Analyses included 200 adults with ADHD (mean age 33.0 years; 60% self-reporting moderate severity); the mean (SD) Adult ADHD Self-Report Scale-v1.1 score was 45.9 (12.4). Overall, patients valued speed of onset most and risk of rebound least. Three population groups with distinct preferences were identified: side effect-driven (n=69, 35%), quick onset-driven (n=47, 24%) and quick onset and long duration-driven (n=84, 42%).

CONCLUSION

This study shows differences in how adults with ADHD value and assess benefit-risk trade-offs when considering the desired attributes of stimulant treatments, highlighting the importance of patient-physician shared decision-making to optimize the desired benefits of individualized treatment.

Adult ADHD: Questioning Diagnosis and Treatment in a Patient with Multiple Psychiatric Comorbidities

Adult Attention-Deficit/Hyperactivity Disorder (ADHD) is a contentious diagnostic issue, which has been increasing in prevalence in recent years, and is often comorbid with other psychiatric disorders. This report presents a detailed account of a clinical case involving a middle-aged man with a history of recurrent depressive episodes and an unsubstantiated diagnosis of ADHD, treated with stimulants. There is persistent debate around the use of psychostimulants both in adult ADHD and in the treatment of depression. Despite promising activating properties, psychostimulants carry significant risks of misuse and substance use disorder. In this report, we consider the potential benefits and adverse effects of stimulants in the treatment of adult ADHD and mood disorders and review the learning points of this complicated, but not uncommon, clinical case.

Event related potentials study of aberrations in voice control mechanisms in adults with attention deficit hyperactivity disorder

OBJECTIVE

The present study was designed to test for neural signs of impulsivity related to voice motor control in young adults with ADHD using EEG recordings in a voice pitch perturbation paradigm.

METHODS

Two age-matched groups of young adults were presented with brief pitch shifts of auditory feedback during vocalization. Compensatory behavioral and corresponding bioelectrical brain responses were elicited by the pitch-shifted voice feedback.

RESULTS

The analysis of bioelectrical responses showed that the ADHD group had shorter peak latency and onset time of motor-related bioelectrical brain responses as compared to the controls.

CONCLUSIONS

These results were interpreted to suggest differences in executive functions between ADHD and control participants.

SIGNIFICANCE

We hypothesize that more rapid motor-related bioelectrical responses found in the present study may be a manifestation of impulsiveness in adults with ADHD at the involuntary level of voice control.

Pharmaco-MEG evidence for attention related hyper-connectivity between auditory and prefrontal cortices in ADHD

The ability to attend to particular stimuli while ignoring others is crucial in goal-directed activities and has been linked with prefrontal cortical regions, including the dorsolateral prefrontal cortex (DLPFC). Both hyper- and hypo-activation in the DLPFC has been reported in patients with attention-deficit/hyperactivity disorder (ADHD) during many different cognitive tasks, but the network-level effects of such aberrant activity remain largely unknown. Using magnetoencephalography (MEG), we examined functional connectivity between regions of the DLPFC and the modality-specific auditory cortices during an auditory attention task in medicated and un-medicated adults with ADHD, and those without ADHD. Participants completed an attention task in two separate sessions (medicated/un-medicated), and each session consisted of two blocks (attend and no-attend). All MEG data were coregistered to structural MRI, corrected for head motion, and projected into source space. Subsequently, we computed the phase coherence (i.e., functional connectivity) between DLPFC regions and the auditory cortices. We found that un-medicated adults with ADHD exhibited greater phase coherence in the beta (14-30Hz) and gamma frequency (30-56Hz) range in attend and no-attend conditions compared to controls. Stimulant medication attenuated these differences, but did not fully eliminate them. These results suggest that aberrant bottom-up processing may engulf executive resources in ADHD.

Estimating the passage of minutes: deviant oscillatory frontal activity in medicated and unmedicated ADHD

OBJECTIVE

Attention-deficit/hyperactivity disorder (ADHD) is a common and extensively treated psychiatric disorder in children, which often persists into adulthood. The core diagnostic symptoms include inappropriate levels of hyperactivity, impulsivity, and/or pervasive inattention. Another crucial aspect of the disorder involves aberrations in temporal perception, which have been well documented in behavioral studies and, recently, have been the focus of neuroimaging studies. These functional magnetic resonance imaging studies have shown reduced activation in anterior cingulate and prefrontal cortices in ADHD using a time-interval discrimination task, whereby participants distinguish intervals differing by only hundreds of milliseconds.

METHOD

We used magnetoencephalography (MEG) to evaluate the cortical network serving temporal perception during a continuous, long-duration (in minutes) time estimation experiment. Briefly, medicated and unmedicated persons with ADHD, and a control group responded each time they estimated 60 s had elapsed for an undisclosed amount of time in two separate MEG sessions. All MEG data were transformed into regional source activity, and subjected to spectral analyses to derive amplitude estimates of gamma-band activity.

RESULTS

Compared to controls, unmedicated patients were less accurate time estimators and had weaker gamma activity in the anterior cingulate, supplementary motor area, and left prefrontal cortex. After medication, these patients exhibited small but significant increases in gamma across these same neural regions and significant improvements in time estimation accuracy, which correlated with the gamma activity increases.

CONCLUSION

We found deficient gamma activity in brain areas known to be crucial for timing functions, which may underlie the day-to-day abnormalities in time perception that are common in ADHD.

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.

Treating attention-deficit/hyperactivity disorder in adults: focus on once-daily medications

OBJECTIVE

To review the efficacy, safety, and abuse liability of approved treatments in adults with attention-deficit/hyperactivity disorder (ADHD), with a focus on once-daily medications.

DATA SOURCES

PubMed was searched for relevant studies/reviews in English from 2002 to 2011 on adult ADHD treatments.

STUDY SELECTION

Keywords used in the search were ADHD, adults, and treatment. Limits included only clinical trials, meta-analyses, randomized controlled trials, and reviews including adults (aged ≥ 19 years).

DATA EXTRACTION

Selection criteria returned 471 publications. Retrieved studies were excluded if they primarily focused on children, treatments not indicated for ADHD, or ADHD and comorbid conditions.

DATA SYNTHESIS

An epidemiologic survey revealed that 10.9% of adults identified with ADHD had received treatment during the prior 12 months. Treatments for ADHD in adults include pharmacologic and nonpharmacologic options. US Food and Drug Administration-approved long-acting stimulants and a nonstimulant with proven efficacy and safety profiles have been developed and include osmotic-release oral system methylphenidate hydrochloride (OROS-methylphenidate), extended-release dexmethylphenidate hydrochloride, mixed amphetamine salts extended release (MAS-XR), the nonstimulant atomoxetine hydrochloride, and the prodrug lisdexamfetamine dimesylate. Long-acting stimulants differ in formulation characteristics used to achieve extended release, with OROS-methylphenidate employing an osmotic-release technology, extended-release dexmethylphenidate hydrochloride and MAS-XR using pH-dependent beads, and lisdexamfetamine dimesylate using prodrug technology. These features variably affect pharmacokinetic characteristics, duration of action, and abuse liability. While all long-acting medications have varied pharmacokinetic features, mechanism of action, and duration of effect, all are generally efficacious and safety profiles are similar.

CONCLUSION

Approved long-acting treatments in adults with ADHD were effective in improving symptoms and were generally well tolerated.

Intranasal versus oral administration of lisdexamfetamine dimesylate: a randomized, open-label, two-period, crossover, single-dose, single-centre pharmacokinetic study in healthy adult men

BACKGROUND AND OBJECTIVE

Data on pharmacokinetic parameters of the prodrug stimulant lisdexamfetamine dimesylate via alternate routes of administration are limited. The pharmacokinetics of d-amphetamine derived from lisdexamfetamine dimesylate after single oral (PO) versus intranasal (IN) administration of lisdexamfetamine dimesylate were compared.

METHODS

In this randomized, two-period, crossover study, healthy men without a history of substance abuse were administered single PO or IN (radiolabelled with ≤100 μCi (99m)Tc-diethylenetriamine-pentaacetic acid and confirmed by scintigraphy) lisdexamfetamine dimesylate 50 mg ≥7 days apart. Serial blood samples were drawn to measure d-amphetamine and intact lisdexamfetamine at 0 (pre-dose), 15, 30 and 45 minutes and at 1, 1.5, 2, 3, 4, 5, 6, 8, 12, 16, 24, 36, 48 and 72 hours post-dose for PO administration and at 0 (pre-dose), 5, 10, 15, 20, 30, 45 minutes and 1, 1.5, 2, 3, 4, 5, 6, 8, 12, 16, 24, 36, 48 and 72 hours post-dose for IN administration. Treatment-emergent adverse events (TEAEs) were assessed.

RESULTS

Eighteen subjects were enrolled and completed the study. The mean ± SD maximum observed plasma concentration (C(max)) and area under the plasma concentration-time curve from time zero to time of last measurable concentration (AUC(last)) of d-amphetamine following PO administration of lisdexamfetamine dimesylate were 37.6 ± 4.54 ng/mL and 719.1 ± 157.05 ng · h/mL, respectively; after IN administration, these parameters were 35.9 ± 6.49 ng/mL and 690.5 ± 157.05 ng · h/mL, respectively. PO and IN administration demonstrated similar median time to reach C(max) (t(max)) for d-amphetamine: 5 hours for PO administration versus 4 hours for IN administration. Mean ± SD elimination half-life (t(1/2)) values were also similar for PO (11.6 ± 2.8 hours) and IN (11.3 ± 1.8 hours) lisdexamfetamine dimesylate. TEAEs after PO and IN administration were reported by 27.8% of subjects (5/18) and 38.9% of subjects (7/18), respectively; all AEs were mild or moderate in severity, and TEAEs such as anorexia, dry mouth, headache and nausea were consistent with known amphetamine effects.

CONCLUSION

IN administration of lisdexamfetamine dimesylate resulted in d-amphetamine plasma concentrations and systemic exposure to d-amphetamine comparable to those seen with PO administration. Subject variability for d-amphetamine pharmacokinetic parameters was low. Both PO and IN lisdexamfetamine dimesylate demonstrated a tolerability profile similar to that of other long-acting stimulants.

A comparative analysis of health-related quality of life and family impact between children with ADHD treated in a general pediatric clinic and a psychiatric clinic utilizing the PedsQL

OBJECTIVE

To evaluate health-related quality of life (HRQOL) from the perspective of children with ADHD and their parents being seen in a Pediatric Clinic in comparison to healthy children and children with ADHD being seen in a Psychiatric Clinic.

METHOD

Participants were children with a physician diagnosis of ADHD ages 5-18 years and their parents (n=17, General Pediatric Clinic; n=181, Psychiatric Clinic). Children and parents completed the PedsQL™ 4.0 Generic Core Scales. Parents completed the PedsQL Family Impact Module and Vanderbilt ADHD Diagnostic Rating Scales.

RESULTS

Pediatric patients with ADHD being seen in the Pediatric Clinic demonstrated substantially lower HRQOL in comparison to the matched healthy sample, and significantly higher HRQOL and family functioning than pediatric patients with ADHD being seen in the Psychiatric Clinic.

CONCLUSION

These data demonstrate the substantial negative impact of ADHD on HRQOL from the perspective of both children and parents.).

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.

Chronic low dose Adderall XR down-regulates cfos expression in infantile and prepubertal rat striatum and cortex

We previously reported that treatment of prepubertal male rats with low, injected or oral, doses of methylphenidate stimulated cfos, fosB and arc expression in many areas of the developing brain. In the present study our objective was to determine whether the widely prescribed psychostimulant Adderall XR (ADD) exerted similar effects in infantile and prepubertal rat brain. We report here, for the first time, that low threshold doses of oral ADD, an extended-release mixture of amphetamine salts, now routinely used for the treatment of Attention Deficit Hyperactivity Disorder (ADHD), also increased cfos expression in infantile (postnatal day 10; PD10) and prepubertal (PD24) rat brain. These threshold doses were correlated with blood levels of amphetamine determined by liquid chromatography-mass spectrometry. Moreover, we observed that chronic treatment with oral ADD (1.6 mg/kg; x 14 days) not only significantly down-regulated cfos expression following a final challenge dose of ADD in prepubertal (PD24) rat striatum and cortex, quantified in terms of FOS immunoreactivity (FOS-ir), but did so at a daily dose that was without effect with methylphenidate (MPH); that is a much higher oral dose of MPH (7.5 mg/kg; x 14 days) failed to induce down-regulation of cfos expression. Similar experiments in infantile rats (PD10), but using a threshold injected dose of ADD (1.25 mg/kg sc) also significantly reduced striatal and cingulate cortical FOS-ir. An additional finding in the prepubertal rats was that oral ADD-induced FOS-ir was observed in the cerebral cortex following doses lower than the threshold dose necessary to increase FOS-ir in the striatum. This was not the case in the PD10 rats. In conclusion, our efforts to calibrate biological responses, such as immediate early gene expression, to clinically relevant blood levels of stimulants confirmed that expression of cfos is very sensitive to repeated low doses of Adderall XR. It is now feasible to examine whether other genes are also affected in these young rats and if the changes we report are reversible. The implications of such studies should be relevant to the putative effects of psychostimulant treatment of very young children.

Clinical recommendations in current practice guidelines for diagnosis and treatment of ADHD in adults

Attention-deficit/hyperactivity disorder (ADHD) is a lifelong neurodevelopmental disorder in which approximately two thirds of patients experience impairment in adulthood. Although some adults with ADHD were diagnosed as children, many are first diagnosed as adults. This poses particular challenges given the limited familiarity with ADHD of many adult mental health services. As a result, several organizations, including the Canadian ADHD Resource Alliance, the American Academy of Child and Adolescent Psychiatry, the National Institutes of Health, and the British Association for Psychopharmacology, have developed practice guidelines for the assessment and treatment of adults with ADHD. This article reviews those guidelines in order to examine current best practices in adult ADHD. There is considerable agreement among these guidelines, which should be a critical part of moving from emerging knowledge to patient care, although both empirical evaluation and ongoing updates as new knowledge emerges will be important for their future development.

Stimulant therapy in the management of ADHD: mixed amphetamine salts (extended release)

The efficacy of amphetamines in the management of attention-deficit/hyperactivity disorder (ADHD) is well established. However, their value in improving the symptoms of ADHD has been compromised by concerns about compliance, abuse potential and adverse events. An extended-release formulation of mixed amphetamine salts (MAS XR) provided the first long-acting amphetamine formulation, and thus, filled an important gap in available treatments for ADHD. MAS XR has been shown to improve ADHD symptoms in children, adolescents and adults in both short- and long-term studies. The drug is generally well tolerated in clinical trials. Although its safety profile in patients with concomitant cardiovascular conditions in a real-world setting has yet to be fully evaluated, a tolerability study of mixed amphetamine salts in adults with ADHD who were being treated for primary essential hypertension showed that these patients can be safely treated with MAS XR.

Effect of two different methods of initiating atomoxetine on the adverse event profile of atomoxetine

OBJECTIVE

To compare the effects of two different methods for initiating atomoxetine in terms of the incidence of early adverse events.

METHOD

Data on atomoxetine treatment-emergent adverse events in youths, ages 6 to 18 years, were analyzed from five randomized, double-blind, placebo-controlled, acute-phase studies. Two studies involve once-daily dosing and titration to 1.2 mg/kg/day over 3 days (fast/once daily, n = 234) and three involve twice-daily dosing and titration to a dose of 1.2 mg/kg/day over at least 2 weeks (slow/twice daily, n = 213).

RESULTS

During the first 2 weeks of treatment, fast/once daily titration patients showed higher rates of spontaneously reported adverse events than patients in the slow/twice daily titration group. This included decreased appetite (14.3% versus 8.0%, p = .036) and somnolence (14.3% versus 4.2%, p < .001). Patients in the slow/twice daily group showed higher rates of headache (7.4% versus 16.9%, p = .003). Analysis of the studies' overall acute treatment phases revealed significantly higher rates in the fast/once daily group only for somnolence. No significant differences were seen in completion rates or reasons for discontinuation.

CONCLUSIONS

When starting atomoxetine, the risk of adverse events within the first few weeks of treatment may be lower if patients are dosed twice daily and titrated to the 1.2 mg/kg/day total daily dose over the first week.

The PedsQL as a patient-reported outcome in children and adolescents with Attention-Deficit/Hyperactivity Disorder: a population-based study

BACKGROUND

Attention-Deficit/Hyperactivity Disorder (ADHD) is the most common chronic mental health condition in children and adolescents. The application of health-related quality of life (HRQOL) as a pediatric population health measure may facilitate risk assessment and resource allocation, the identification of health disparities, and the determination of health outcomes from interventions and policy decisions for children and adolescents with ADHD at the local community, state, and national health level.

METHODS

An analysis from an existing statewide database to determine the feasibility, reliability, and validity of the 23-item PedsQL 4.0 (Pediatric Quality of Life Inventory) Generic Core Scales as a patient-reported outcome (PRO) measure of pediatric population health for children and adolescents with ADHD. The PedsQL 4.0 Generic Core Scales (Physical, Emotional, Social, School Functioning) were completed by families through a statewide mail survey to evaluate the HRQOL of new enrollees in the State of California State's Children's Health Insurance Program (SCHIP). Seventy-two children ages 5-16 self-reported their HRQOL.

RESULTS

The PedsQL 4.0 evidenced minimal missing responses, achieved excellent reliability for the Total Scale Score (alpha = 0.92 child self-report, 0.92 parent proxy-report), and distinguished between healthy children and children with ADHD. Children with ADHD self-reported severely impaired psychosocial functioning, comparable to children with newly-diagnosed cancer and children with cerebral palsy.

CONCLUSION

The results suggest that population health monitoring may identify children with ADHD at risk for adverse HRQOL. The implications of measuring pediatric HRQOL for evaluating the population health outcomes of children with ADHD internationally are discussed.