A Placebo-Controlled Trial of Lisdexamfetamine in the Treatment of Comorbid Sluggish Cognitive Tempo and Adult ADHD.

Objective: To examine the efficacy of lisdexamfetamine (LDX) versus placebo on behavioral attributes of sluggish cognitive tempo (SCT) in adults with attention-deficit/hyperactivity disorder (ADHD) and SCT.Methods: In a randomized crossover trial conducted January 2016-April 2018, 38 adults with DSM-5 ADHD (via the Adult ADHD Clinical Diagnostic Scale v1.2) and SCT were recruited at 2 academic medical centers and assessed for symptoms of ADHD, SCT, executive function deficits, and functional impairment at baseline and weekly during treatment. Participants received 4 weeks of treatment with either LDX (30-70 mg/d; mean = 59.1 ± 14.8 mg/d) or matching placebo (mean = 66.6 ± 9.1 mg/d) with a 2-week washout before switching to the other arm. The ADHD Rating Scale and Barkley Adult ADHD Rating Scale-IV SCT subscale were coprimary outcome measures.Results: There were moderately large treatment effects of LDX vs placebo on SCT ratings in both treatment periods (block 1 effect size = 0.68; block 2 effect size = 0.61), which reached significance only in block 1 owing to carryover effects of the first treatment epoch into the second. Significant effects were also seen for LDX over placebo in ADHD, executive function deficit, and functional impairment ratings, without order effects; no site differences were seen except on the Global Executive Complex score of the Behavior Rating Inventory of Executive Function-Adult Version. No moderating effects of sex, age, race, and ethnicity were seen.Conclusions: Adults with ADHD and comorbid SCT had significant improvement after LDX vs placebo in ratings of SCT, ADHD, executive function deficits, and functional impairment. This is the first study to show improvement in SCT after stimulant therapy in adults with ADHD.Trial Registration: ClinicalTrials.gov identifier: NCT02635035.

Medication Use in the Management of Comorbidities Among Individuals With Autism Spectrum Disorder From a Large Nationwide Insurance Database.

Importance: Although there is no pharmacological treatment for autism spectrum disorder (ASD) itself, behavioral and pharmacological therapies have been used to address its symptoms and common comorbidities. A better understanding of the medications used to manage comorbid conditions in this growing population is critical; however, most previous efforts have been limited in size, duration, and lack of broad representation. Objective: To use a nationally representative database to uncover trends in the prevalence of co-occurring conditions and medication use in the management of symptoms and comorbidities over time among US individuals with ASD. Design, Setting, and Participants: This retrospective, population-based cohort study mined a nationwide, managed health plan claims database containing more than 86 million unique members. Data from January 1, 2014, to December 31, 2019, were used to analyze prescription frequency and diagnoses of comorbidities. A total of 26 722 individuals with ASD who had been prescribed at least 1 of 24 medications most commonly prescribed to treat ASD symptoms or comorbidities during the 6-year study period were included in the analysis. Exposures: Diagnosis codes for ASD based on International Classification of Diseases, Ninth Revision, and International Statistical Classification of Diseases and Related Health Problems, Tenth Revision. Main Outcomes and Measures: Quantitative estimates of prescription frequency for the 24 most commonly prescribed medications among the study cohort and the most common comorbidities associated with each medication in this population. Results: Among the 26 722 individuals with ASD included in the analysis (77.7% male; mean [SD] age, 14.45 [9.40] years), polypharmacy was common, ranging from 28.6% to 31.5%. Individuals' prescription regimens changed frequently within medication classes, rather than between classes. The prescription frequency of a specific medication varied considerably, depending on the coexisting diagnosis of a given comorbidity. Of the 24 medications assessed, 15 were associated with at least a 15% prevalence of a mood disorder, and 11 were associated with at least a 15% prevalence of attention-deficit/hyperactivity disorder. For patients taking antipsychotics, the 2 most common comorbidities were combined type attention-deficit/hyperactivity disorder (11.6%-17.8%) and anxiety disorder (13.1%-30.1%). Conclusions and Relevance: This study demonstrated considerable variability and transiency in the use of prescription medications by US clinicians to manage symptoms and comorbidities associated with ASD. These findings support the importance of early and ongoing surveillance of patients with ASD and co-occurring conditions and offer clinicians insight on the targeted therapies most commonly used to manage co-occurring conditions. Future research and policy efforts are critical to assess the extent to which pharmacological management of comorbidities affects quality of life and functioning in patients with ASD while continuing to optimize clinical guidelines, to ensure effective care for this growing population.

Open-label pilot study of lisdexamfetamine for cocaine use disorder.

Background: Cocaine use disorder (CUD) is a substantial public health problem with no FDA-approved medication treatments. Psychostimulants have shown promise as pharmacotherapy for CUD. Lisdexamfetamine, a novel prodrug psychostimulant, is roughly 40-50% as potent as dextroamphetamine.Objectives: To evaluate the safety, tolerability, and optimal dosing of lisdexamfetamine for treating CUD.Methods: Open-label, 8-week trial of 17 CUD adults. Participants were titrated to the maximum tolerated dose of 140 mg over 2-week period and maintained for 4 weeks, followed by a two-week taper period. The primary outcome measures were the maximum daily dose achieved during the study period and tolerability as measured by medication-related study drop-out.Results: Among the 16 participants with post-enrollment data, the mean dose of lisdexamfetamine achieved was 118.1 mg (standard deviation (SD) = 40.4), mean retention was 6.5 weeks (SD = 2.0), and no participants discontinued study medication due to adverse effects. Four participants had dose reductions due to adverse effects and continued in the trial. Six participants (37.5%) were abstinent for the last 3 weeks of their study participation. Mean dollars of cocaine spent per day significantly decreased from $19.72 at baseline to $7.57 during the last 3 weeks of study participation (t15 = 3.60, p = .003). The mean percent of using days significantly decreased from 25% at baseline to 12% during the last 3 weeks of study participation (t15 = 3.33, p = .005).Conclusion: The use of lisdexamfetamine for CUD in doses ranging to 140 mg daily was safe and generally well tolerated.

Evaluating the reliability of hair analysis in monitoring the compliance of ADHD patients under treatment with Lisdexamphetamine.

Considering the high clinical and forensic relevance of pharmaco-adherence during lisdexamphetamine (LDX) treatment for attention-deficit/hyperactivity disorder (ADHD), the aim here was to evaluate hair analysis as a tool for monitoring compliance in patients currently undergoing long term treatment with LDX, by detecting possible interruptions of medication intake or changes in dosage. For this purpose, a total of 24 patients from an outpatient clinic for ADHD were recruited. Hair and urine samples were taken after three consecutive therapy sessions over a 7-month period and analyzed for amphetamine (AMP) enantiomers and other drugs, using chiral and achiral liquid chromatography-tandem mass spectrometry (LC-MS/MS). Participants also provided information on the condition of their hair, the consumption of illegal psychotropic substances and the regularity of taking LDX. Two participants withdrew from the study early. Urine analyses were positive for D-AMP in all urine samples and therapy sessions, except in two patients who did not take LDX on a daily basis. D-AMP was detected in all hair samples; however, no correlation was found between prescribed dose/day and D-AMP concentrations in proximal hair segments. Qualitative interpretation of hair analysis showed that 18 of the 22 study completers were compliant concerning the intake of LDX without additional consumption of illegal D,L-AMP. Analysis of urine taken during the therapy sessions showed no correlation between D-AMP concentrations and prescribed dosage, with or without normalization for creatinine. In conclusion, chiral LC-MS/MS hair analysis might represent a non-invasive way to confirm LDX use within the approximate period covered by the hair segment tested, but it does not allow for quantitative therapeutic drug monitoring because of interindividual variability of concentrations in hair. Drug concentrations in hair at different stages of long-term treatment should thus be interpreted with caution by clinicians and forensic experts alike when making assessments of treatment adherence.

Pharmacokinetics of Coadministered Viloxazine Extended-Release (SPN-812) and Lisdexamfetamine in Healthy Adults.

BACKGROUND: Viloxazine extended-release is a novel nonstimulant under investigation as a potential treatment for attention-deficit/hyperactivity disorder (ADHD). Given the potential for viloxazine extended-release to be co-administered with stimulant ADHD pharmacotherapies, this trial investigated the pharmacokinetics and safety of combination viloxazine extended-release + lisdexamfetamine dimesylate (lisdexamfetamine) versus viloxazine extended-release and lisdexamfetamine alone. METHODS: In this single-center, cross-over, open-label trial, healthy, non-ADHD adults received single oral doses of 700 mg viloxazine extended-release alone, 50 mg lisdexamfetamine alone, and a combination of viloxazine extended-release (700 mg) + lisdexamfetamine (50 mg), with blood samples collected over 4 days postadministration. The active drug in viloxazine extended-release (viloxazine) and primary metabolite of lisdexamfetamine (d-amphetamine) were measured using chromatographic tandem mass spectrometry. Safety assessments included adverse events, vital signs, echocardiograms, and clinical laboratory evaluations. RESULTS: Thirty-six adults were enrolled, and 34 completed the trial. The least squares geometric mean ratios are reported as [combination / single drug (90% confidence intervals)]. Viloxazine extended-release: Cmax = 95.96% (91.33-100.82), area under the concentration-time curve from 0 to the last measurable time (AUC0-t) = 99.19% (96.53-101.91), and area under the concentration-time curve from 0 to infinity (AUCinf) = 99.23% (96.61-101.93). Lisdexamfetamine: Cmax = 112.78% (109.93-115.71), AUC0-t = 109.64% (105.25-114.22), and AUCinf = 109.52% (105.19-114.03). All reported adverse events, except 1 (moderate vomiting), were mild in severity. CONCLUSIONS: Co-administration of viloxazine extended-release and lisdexamfetamine did not impact the pharmacokinetics of viloxazine or d-amphetamine relative to administration of either drug alone. After single dose administration, the combination appeared to be safe and well tolerated.

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.

Population pharmacokinetic and exposure-response analyses of d-amphetamine after administration of lisdexamfetamine dimesylate in Japanese pediatric ADHD patients.

Lisdexamfetamine dimesylate, a prodrug of d-amphetamine, has been approved for treatment of attention-deficit/hyperactivity disorder (ADHD). The purposes of this study were constructing a population pharmacokinetic model of d-amphetamine after dosing of lisdexamfetamine dimesylate and assessing influential factors on the pharmacokinetics of d-amphetamine in Japanese pediatric patients with ADHD. Additionally, the exposure-response relationship was evaluated for Japanese pediatric patients with ADHD using a clinical rating scale, the ADHD Rating Scale IV (ADHD RS-IV, efficacy endpoint) total score as a response index. A total of 1365 points of plasma d-amphetamine concentrations from pediatric patients (6-17 years) with ADHD in clinical studies conducted in Japan and the US were employed for the population pharmacokinetic analysis. The plasma concentrations of d-amphetamine in pediatric patients with ADHD were well described by a one-compartment model with first-order absorption and lag time. The effects of body weight and ethnicity (Japanese or non-Japanese) on apparent total body clearance and the effect of body weight on apparent volume of distribution were incorporated into the final model. No clear exposure-dependent reduction was evident from the ADHD RS-IV total score, whereas the reductions were greater for the lisdexamfetamine dimesylate treatment groups compared with the placebo group regardless of exposure to d-amphetamine.

Dose Adjustment of Stimulants for Children with Attention-Deficit/Hyperactivity Disorder: A Retrospective Chart Review of the Impact of Exceeding Recommended Doses.

BACKGROUND: When children with attention-deficit/hyperactivity disorder (ADHD) are treated with stimulant medication, the dose is established clinically by dose adjustment over time. Little is known about children who are not adequately treated when they reach a designated maximum dose, or the consequences of exceeding this dose. OBJECTIVE: The aim of this study was to determine the characteristics of and side effects observed in children optimised to high dose (HD) versus regular dose (RD) stimulants. METHOD: Children treated by one paediatrician (AP) in Western Sydney, Australia with HD stimulants (n = 52) were identified using an electronic database; controls on RD stimulant (n = 118) were matched by prescription date with the cases' first HD prescription. HD was defined as methylphenidate > 2 mg/kg/day or > 108 mg/day; dexamphetamine > 1 mg/kg/day or > 50 mg/day; lisdexamfetamine > 70 mg/day. In all children, the dose was adjusted over time to optimise the clinical response. Clinical characteristics, anthropometric measures, reported side effects and reasons for dose changes were extracted from the clinical charts by LR, VS and CS. The HD and RD cohorts were compared using chi-square for categorical data and t tests for continuous data. RESULTS: The HD cohort included more boys (88% vs 75%, p = 0.041) and more oppositional defiant disorder (83% vs 55%, p = 0.001). They started stimulants younger (6.40 ± 1.67 vs 8.28 ± 2.77 years, p < 0.001) and had more growth attenuation (Δ height z-score - 0.41 ± 0.55 vs - 0.09 ± 0.58, p = 0.001; Δ weight z-score - 0.56 ± 0.82 vs - 0.18 ± 0.66, p = 0.002). The growth attenuation mainly occurred before the dose reached the HD range. Diminishing stimulant effectiveness was the commonest reason for a dose increase in either cohort, the most prominent recurring symptoms being persistent anger/aggression in the HD and poor concentration in the RD cohort. The commonest reason for dose reduction in the HD cohort was that a dose increase gave no added benefit; dose reduction or change of drug due to subdued/depressed behaviour was more frequent in RD children. Apart from growth attenuation, no serious complications were reported in the HD group. CONCLUSIONS: In this preliminary study, dose adjustment over time in some patients meant using higher doses than those generally recommended. These children experienced more growth attenuation but recorded no other significant treatment complications. Determining the dose purely on clinical grounds by careful dose adjustment over time appears reasonable, but more data on this issue is required to clarify the efficacy and tolerability of exceeding the recommended doses of stimulants when treating ADHD.

Lisdexamfetamine Dimesylate for Preschool Children with Attention-Deficit/Hyperactivity Disorder.

Objectives: Describe the safety and tolerability of lisdexamfetamine dimesylate (LDX) and provide data on clinical effects for efficacy-related endpoints and pharmacokinetics in preschool-aged children with attention-deficit/hyperactivity disorder (ADHD). Methods: This phase 2, multicenter, open-label, dose-optimization study (ClinicalTrials.gov registry: NCT02402166) was conducted at seven U.S. sites between April 15, 2015, and June 30, 2016. Children (4-5 years of age) meeting Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria for ADHD and having ADHD Rating Scale-IV Preschool version (ADHD-RS-IV-PS) total scores ≥28 (boys) or ≥24 (girls) were eligible. Open-label LDX (8-week duration) was initiated at 5 mg and titrated to 30 mg until achieving an optimal dose. Assessments included treatment-emergent adverse events (TEAEs), vital sign changes, ADHD-RS-IV-PS total score changes, and pharmacokinetic evaluations. Results: Among 24 participants, the most frequently reported TEAE was decreased appetite (8/24; 33%). At week 8/early termination, mean (standard deviation) systolic and diastolic blood pressure and pulse changes from baseline were -1.1 (7.31) and 1.5 (6.93) mmHg and -0.8 (12.75) bpm, respectively. The mean (95% confidence interval) change from baseline ADHD-RS-IV-PS total score at the final on-treatment assessment was -26.1 (-32.2 to -20.0). Pharmacokinetic parameters of d-amphetamine, a major active metabolite of LDX, were characterized: d-amphetamine exposure increased with LDX dose; mean tmax and t1/2, respectively, ranged from 4.00 to 4.23 hours and 7.18 to 8.46 hours. Conclusions: In preschool-aged children with ADHD, LDX was generally well tolerated and reduced ADHD symptoms, consistent with observations in children 6-17 years of age. Based on these findings, a starting LDX dose as low as 5 mg in phase 3 studies in preschool-aged children is supported.

Assessment of Amphetamine Withdrawal Symptoms of Lisdexamfetamine Dimesylate Treatment for Adults With Binge-Eating Disorder.

OBJECTIVE: To determine whether physical dependence developed during lisdexamfetamine dimesylate treatment, as evidenced by presence of withdrawal symptoms after treatment cessation in adults with binge-eating disorder (BED) treated for up to 38 weeks. METHODS: Three studies enrolled adults with DSM-IV-TR-defined BED. In two 12-week, randomized, double-blind, placebo-controlled studies conducted from November 2012 to September 2013, participants were treated with placebo or dose-optimized lisdexamfetamine (50 or 70 mg). In a double-blind, placebo-controlled, randomized-withdrawal maintenance-of-efficacy study conducted from January 2014 to April 2015, participants categorized as responders after 12 weeks of open-label lisdexamfetamine (50 or 70 mg) were randomized to continued lisdexamfetamine or placebo for 26 weeks. The Amphetamine Cessation Symptom Assessment (ACSA), a 16-item self-report instrument (total score: 0-64), assessed withdrawal experiences. Mean ± SD ACSA scores and medians are presented for study completers. RESULTS: In the short-term efficacy studies, mean ± SD ACSA aggregate scores for placebo and lisdexamfetamine (pooled data) were 7.0 ± 7.60 (n = 275) and 4.9 ± 6.41 (n = 271), respectively, on the day of the last dose at week 12/early termination (ET) and 4.8 ± 6.82 (n = 234) and 5.5 ± 7.50 (n = 221) on day 7 after the last dose. In the maintenance-of-efficacy study, mean ± SD ACSA aggregate scores for placebo and lisdexamfetamine were 4.8 ± 6.67 (n = 44) and 4.7 ± 7.78 (n = 85) on the day of the last dose at week 38/ET and 3.9 ± 5.75 (n = 37) and 5.2 ± 7.93 (n = 71) on day 7 after the last dose. CONCLUSIONS: Study results suggest that abrupt lisdexamfetamine termination was not associated with amphetamine withdrawal symptoms at the exposure durations and therapeutic doses analyzed. TRIAL REGISTRATION: Clinicaltrials.gov identifiers: NCT01718483, NCT01718509, and NCT02009163.

Lisdexamfetamine suppresses instrumental and consummatory behaviors supported by foods with varying degrees of palatability: Exploration of a binge-like eating model.

Diets high in sugar or fat are associated with multiple health conditions, including binge eating disorder (BED). BED affects approximately 2% of the US adult population, and occurs more frequently in females. It is important to develop animal models of palatable food consumption and food seeking that may have relevance for BED and other conditions associated with excessive food intake. The catecholamine uptake blocker and d-amphetamine prodrug lisdexamfetamine is used to treat BED. The present experiments studied the effect of lisdexamfetamine on food intake and food-reinforced effort-based choice in female Wistar rats. Three groups of rats received different food exposure conditions in the home cage randomly spread over several weeks: a chocolate exposure group (CE; brief access of chocolate and additional lab chow, n = 15), a lab chow exposure (LChE) group given additional access to lab chow (n = 8), and a third group given empty food dishes (n = 7). In tests of food intake under non-restricted conditions, lisdexamfetamine (0.1875-1.5 mg/kg IP) significantly reduced intake of both chocolate and chow in the CE group. In the LChE group, there was a trend towards reduced chow intake induced by lisdexamfetamine. All rats were trained on a Progressive Ratio/chow feeding choice task, in which they had a choice between working for high carbohydrate chocolate flavored pellets by lever pressing vs. approaching and consuming a concurrently available lab chow. The LChE group and the empty food dish group were combined to create one control group (n = 15). There was a significant overall dose-related suppressive effect of lisdexamfetamine on lever pressing but no group difference, and no dose x group interaction. Lisdexamfetamine significantly decreased chow intake in the CE group, but not in the control group. In conclusion, lisdexamfetamine affected both food intake and food-reinforced operant behavior, with larger effects seen in the group exposed to chocolate.

Long-term study of lisdexamfetamine dimesylate in Japanese children and adolescents with attention-deficit/hyperactivity disorder.

AIMS: As an extension of a phase 2/3 study evaluating the efficacy and safety of lisdexamfetamine dimesylate (LDX) 30, 50, or 70 mg/d for 4 weeks in Japanese patients aged 6-17 years with attention-deficit/hyperactivity disorder (ADHD), this study evaluated its long-term safety and efficacy. METHODS: This was a multicenter, open-label study of LDX for 53 weeks. Safety was assessed by regular medical examination for treatment-emergent adverse events (TEAEs); regular recording of body weight, vital signs, and laboratory test values; and completion of dependence questionnaires. Efficacy was assessed using Japanese versions of the ADHD-Rating Scale-IV (ADHD-RS-IV) and Conners' 3rd edition Parent Rating Scale (Conners 3); plus Clinical Global Impression-Improvement (CGI-I), Clinical Global Impression-Severity, and Parent Global Assessment (PGA) scales. RESULTS: Of 132 enrolled patients, 104 completed the trial. Most frequent treatment-related TEAEs were decreased appetite (73.5%), initial insomnia (39.4%), and weight decrease (22.0%). Most TEAEs were mild (82.6% of patients). There were no serious or severe TEAEs or deaths. No treatment-related TEAEs were associated with blood pressure or pulse rate, and no patient had a QTcF interval >500 ms. Statistically significant improvement from baseline to week 53 was observed in the mean ADHD-Rating Scale-IV total score and mean Conners 3 subscale scores. Most patients showed improvement on the CGI-I (78%) and PGA (76.5%) scales. CONCLUSIONS: No significant safety issues were observed with LDX 30, 50, or 70 mg/d administered for 1 year in Japanese children and adolescents with ADHD. LDX was associated with long-term reductions in ADHD symptoms and severity.

A phase 1, randomized, double-blind, placebo-controlled study to evaluate the safety, tolerability, and pharmacokinetics of single and multiple doses of lisdexamfetamine dimesylate in Japanese and Caucasian healthy adult subjects.

AIM: To assess safety, tolerability, and pharmacokinetics of lisdexamfetamine dimesylate in Japanese and Caucasian healthy adults. METHODS: A phase 1, double-blind, randomized, placebo-controlled, single- and multiple-dose study in Japanese and Caucasian subjects. Subjects received lisdexamfetamine 20 mg or placebo on Day 1, then lisdexamfetamine 20 mg/d (Days 4-8), 50 mg/d (Days 9-13), 70 mg/d (Days 14-18), or matching placebo. Pharmacokinetic parameters for lisdexamfetamine and d-amphetamine were estimated by noncompartmental analysis. RESULTS: Fifteen Japanese and 19 Caucasian subjects were enrolled and randomized. The lisdexamfetamine and d-amphetamine plasma concentration-time curves were similar for both ethnic groups following single and multiple doses. Mean area under the concentration-time curves for d-amphetamine were higher (by 11%-15%) in Japanese than Caucasian subjects following multiple dosing of lisdexamfetamine. Mean bodyweight was 17% lower in Japanese than Caucasian subjects. Weight-corrected means for oral clearance were similar in both ethnic groups, with no unexpected accumulation of d-amphetamine. Lisdexamfetamine was generally well tolerated by both ethnic groups, with no serious adverse events reported. The 10/12 Japanese and 11/16 Caucasian subjects who received lisdexamfetamine completed the study; two Japanese and three Caucasian subjects discontinued due to adverse events. Most adverse events were of mild severity. CONCLUSION: Pharmacokinetics were generally similar for Japanese and Caucasian subjects; the minor differences observed were likely due to bodyweight differences in the two ethnic groups. Lisdexamfetamine was generally well tolerated. Adverse events were consistent with the established safety profile of lisdexamfetamine and were similar in both ethnic groups.

Examining the heterogeneity of treatment patterns in attention deficit hyperactivity disorder among children and adolescents in the Texas Medicaid population: modeling suboptimal treatment response.

Objectives: To examine suboptimal responses (SR) in attention deficit hyperactivity disorder (ADHD) among pediatric patients in the Texas Medicaid program receiving osmotic-release oral system methylphenidate (OROS-MPH) or lisdexamfetamine (LDX) and apply an SR prediction model to identify patients most likely to experience an SR to either OROS-MPH or LDX therapies. Methods: A retrospective cohort study was conducted using Texas Medicaid claims data of ADHD children and adolescents (6-17 years of age) initiating OROS-MPH or LDX. Primary SR endpoints were drug discontinuation, switching, and augmentation 12-months post-ADHD drug initiation. Logistic regression models were developed to predict SR to OROS-MPH and LDX in 1:1 matched groups of children and adolescent cohorts. Results: A total of 3,633 children and 1,611 adolescents were matched for each cohort. SR was observed among more children (76.4% vs 72.3%; p < 0.001) and adolescents (82.7% vs 78.2%; p = 0.002) initiating OROS-MPH compared to LDX. Patient sub-groups with the highest predicted risk of OROS-MPH SR experienced significantly lower observed SR rates (p < 0.05) when initiating LDX (children: 80.6% for OROS-MPH vs 75.8% for LDX; OR = 0.75, 95% CI = 0.60-0.94; adolescents: 87.2% for OROS-MPH vs 80.6% for LDX; OR = 0.61, 95% CI = 0.41-0.89). For patients with highest predicted SR rates to LDX, observed SR rates were not significantly different between patients initiating LDX or OROS-MPH. Conclusions: This study demonstrated how a personalized medicine approach using administrative claims data can be used to identify sub-groups of child and adolescent ADHD patients with different risks for suboptimal response with OROS-MPH or LDX in a Medicaid population.

Lisdexamfetamine Dimesylate: A Review in Paediatric ADHD.

Lisdexamfetamine dimesylate (lisdexamfetamine; Elvanse®; Tyvense®), an orally-active dexamfetamine prodrug, is indicated in the EU for the treatment of attention-deficit hyperactivity disorder (ADHD) in children aged ≥ 6 years (including adolescents) when the response to previous methylphenidate (MPH) treatment is clinically inadequate. The original approval of the drug was based on the results of phase III trials in children and adolescents with ADHD who had an inadequate response to previous pharmacotherapy (e.g. MPH) or were treatment naïve. In these studies, short-term treatment with flexibly-dosed lisdexamfetamine demonstrated greater efficacy than atomoxetine, based on a prospective comparison, and osmotic-release oral system (OROS)-MPH, based on a post hoc comparison. Improvements in ADHD symptoms were accompanied by improvements in health-related quality of life and functioning that were maintained as long as treatment with lisdexamfetamine was continued in a long-term extension of one of these trials. In subsequent phase IV head-to-head studies in adolescents with ADHD and an inadequate response to previous pharmacotherapy, lisdexamfetamine demonstrated greater efficacy than OROS-MPH when both medications were force-titrated, but not when they were flexibly-titrated. Lisdexamfetamine was generally well tolerated, with an adverse event profile (e.g. decreased appetite, headache, weight reduction, insomnia and irritability) typical of that reported for other stimulants. Thus, lisdexamfetamine provides an alternative option for the treatment of children and/or adolescents with ADHD who have not responded adequately to previous ADHD pharmacotherapies.

A 12-Month Open-Label Extension Study of the Safety and Tolerability of Lisdexamfetamine Dimesylate for Major Depressive Disorder in Adults.

PURPOSE/BACKGROUND: Psychostimulant augmentation is considered a potential treatment strategy for individuals with major depressive disorder who do not adequately respond to antidepressant monotherapy. The primary objective of this 12-month open-label extension study was to evaluate the safety and tolerability of lisdexamfetamine dimesylate (LDX) as augmentation therapy to an antidepressant in adults with major depressive disorder. METHODS/PROCEDURES: Eligible adults who completed 1 of 3 short-term antecedent LDX augmentation of antidepressant monotherapy studies were treated with dose-optimized LDX (20-70 mg) for up to 52 weeks while continuing on the index antidepressant (escitalopram, sertraline, venlafaxine extended-release, or duloxetine) assigned during the antecedent short-term studies. Safety and tolerability assessments included the occurrence of treatment-emergent adverse events and vital sign changes. FINDINGS/RESULTS: All 3 antecedent studies failed to meet the prespecified primary efficacy endpoint, so this open-label study was terminated early. Headache (15.5% [241/1559]), dry mouth (13.6% [212/1559]), insomnia (13.1% [204/1559]), and decreased appetite (12.1% [189/1559]) were the most frequently reported treatment-emergent adverse events. The greatest mean ± SD increases observed for systolic and diastolic blood pressure and for pulse were 2.6 ± 10.85 and 1.7 ± 7.94 mm Hg and 6.9 ± 10.27 bpm, respectively. Monitoring determined that less than 1% of participants experienced potentially clinically important changes in systolic blood pressure (10 [0.6%]), diastolic blood pressure (8 [0.5%]), or pulse (6 [0.4%]). IMPLICATIONS/CONCLUSIONS: The overall safety and tolerability of long-term LDX augmentation of antidepressant monotherapy was consistent with the profiles of the short-term antecedent studies, with no evidence of new safety signals.

Cognitive Function of Children and Adolescents with Attention-Deficit/Hyperactivity Disorder in a 2-Year Open-Label Study of Lisdexamfetamine Dimesylate.

BACKGROUND: SPD489-404 was the first 2-year safety study of lisdexamfetamine dimesylate in the treatment of attention-deficit/hyperactivity disorder in children and adolescents. In accordance with advice from the European Medicines Agency, assessment of cognitive function was a predefined safety outcome in SPD489-404. OBJECTIVE: The objective of this study was to assess cognitive function over 2 years in study SPD489-404, using the Cambridge Neuropsychological Test Automated Battery (CANTAB). METHODS: Participants aged 6-17 years received dose-optimised open-label lisdexamfetamine dimesylate (30, 50 or 70 mg/day) for 104 weeks. Cognition was assessed using four CANTAB tasks; Delayed Matching to Sample (DMS), Spatial Working Memory (SWM), Stop Signal Task (SST) and Reaction Time (RTI). Key and additional variables were pre-specified for each CANTAB task; groupwise mean percentage changes in key variables from baseline of > 5% were considered potentially clinically significant. RESULTS: All 314 enrolled participants received lisdexamfetamine dimesylate and were included in the safety population, and 191 (60.8%) completed the study. No potentially clinically significant deteriorations from baseline were observed in any key CANTAB variable over the 2 years of the study. Based on predefined thresholds, potentially clinically significant improvements from baseline were observed at 6 months (DMS median reaction time, mean per cent change, - 6.6%; SWM total between-search errors, - 22.8%; SST stop signal reaction time, -18.9%), and at the last on-treatment assessment (DMS median reaction time, - 6.5%; SWM total between-search errors, - 32.6%; SST stop signal reaction time, - 25.7%). CONCLUSIONS: Lisdexamfetamine dimesylate treatment for 2 years was not associated with deterioration of cognitive function in children and adolescents with attention-deficit/hyperactivity disorder. Although improvements in some cognitive measures were observed, lack of a control group makes interpretation of the findings difficult. Further studies of the impact of stimulants on cognition are required. CLINICALTRIALS. GOV IDENTIFIER: NCT01328756.

Safety of pharmacotherapy options for bulimia nervosa and binge eating disorder.

INTRODUCTION: Eating disorders represent a set of psychiatric illnesses with lifelong complications and high relapse rates. Individuals with eating disorders are often stigmatized and clinicians have a limited set of treatments options. Pharmacotherapy has the potential to improve long term compliance and patient commitment to treatment for eating disorders. AREAS COVERED: This review will examine the efficacy and safety profile of the FDA-approved medications for the treatment of bulimia nervosa (BN) and binge eating disorder (BED). This will include the evaluation of fluoxetine for BN, and lisdexamfetamine for BED. Safety information will be review from randomized control trials (RCT), open label trials, and case reports. EXPERT OPINION: Fluoxetine for BN and lisdexamfetamine for BED are relatively safe and well-tolerated. Despite these properties, these two medications represent a limited arsenal for the pharmacological treatment of eating disorders. Thus, more research-based strategies are needed to develop safe, effective, and more targeted therapies for eating disorders.

Lisdexamfetamine: chemistry, pharmacodynamics, pharmacokinetics, and clinical efficacy, safety, and tolerability in the treatment of binge eating disorder.

INTRODUCTION: The indications for lisdexamfetamine (LDX), a central nervous system stimulant, were recently expanded to include treatment of moderate to severe binge eating disorder (BED). Areas covered: This review aims to describe the chemistry and pharmacology of LDX, as well as the clinical trials investigating the efficacy and safety of this medication for the management of BED. Expert opinion: LDX is the first medication with United States Food and Drug Administration approval for the treatment of BED. It is an inactive prodrug of d-amphetamine that extends the half-life of d-amphetamine to allow for once daily dosing. D-amphetamine acts primarily to increase the concentrations of synaptic dopamine and norepinephrine. Metabolism of LDX to d-amphetamine occurs when peptidases in red blood cells cleave the covalent bond between d-amphetamine and l-lysine. D-amphetamine is then further metabolized by CYP2D6. Excretion is primarily through renal mechanisms. In clinical trials, LDX demonstrated statistical and clinical superiority over placebo in reducing binge eating days per week at doses of 50 and 70 mg daily. Commonly reported side effects of LDX include dry mouth, insomnia, weight loss, and headache, and its use should be avoided in patients with known structural cardiac abnormalities, cardiomyopathy, serious heart arrhythmia or coronary artery disease. As with all CNS stimulants, risk of abuse needs to be assessed prior to prescribing.