Memory loss induced by lisdexamfetamine in the rat: A behavioral, electrophysiological, and histopathological Study.

Lisdexamfetamine (LDX) is one of the drugs commonly used to treat attention deficit hyperactivity disorder (ADHD). However, its neurological side effects, particularly on cognition, are not fully understood. The present study focused on memory in rats treated with four weeks of LDX injection. We compared LDX-treated rats with control ones, using several methods to evaluate the behavioral responses and electrophysiological, molecular, and histological properties in the hippocampus. Our findings demonstrated that subchronic administration of LDX impaired behavioral performance in all memory assessment tests (Y maze, Morris Water Maze, and Shuttle box). Although LDX did not alter population spike (PS) amplitude, it increased the field excitatory postsynaptic potential (fEPSP) slope of evoked potentials of LTP components. Also, in addition to an increase in expression of caspase-3 in the hippocampus, which indicates the susceptibility to apoptosis in LDX-treated rats, the number of microglia and astrocytes went up significantly in the LDX group. Moreover, Sholl's analysis showed an increase in the soma size and total process length in both hippocampal astrocytes and microglia. Overall, because of these destructive effects of LDX on the hippocampus, which is one of the critical memory-related areas of the brain, the findings of this investigation provide evidence to show the disruption of memory-related variables following the LDX. However, more research is needed to clarify it.

A Randomized, Phase 3, Double-Blind, Crossover Comparison of Multilayer, Extended-Release Methylphenidate (PRC-063), and Lisdexamfetamine in the Driving Performance of Young Adults With ADHD.

OBJECTIVE: To compare PRC-063 (multilayer-release methylphenidate) and lisdexamfetamine dimesylate (LDX) on the driving performance of young adults with attention deficit hyperactivity disorder (ADHD) in a randomized, double-blind, crossover study. METHOD: Following up to 21 days of each treatment in each treatment course (PRC-063/LDX or LDX/PRC-063), subjects completed a 15-hour driving simulator laboratory assessment. The primary outcome measure was the Tactical Driving Quotient (TDQ) and the Clinical Global Impressions-Improvement (CGI-I) scale was a secondary outcome measure. RESULTS: Forty-four subjects completed the study. PRC-063 and LDX had equivalent effects on driving performance through a 15-hour time period (least square mean difference -0.3 [standard error 1.08], 95% confidence interval [-2.4, 1.8], p = .793). Consistent improvement in CGI-I was observed. The incidence of treatment-emergent adverse events was similar for each treatment sequence. CONCLUSIONS: PRC-063 and LDX had comparable effects on driving performance, from 1 through 15 hours, the last time point measured.

Lisdexamfetamine dimesylate (Vyvanse) toxicosis in a dog.

OBJECTIVE: To describe the presentation, management, and postmortem examination findings in a dog with confirmed lisdexamfetamine dimesylate (LDX) toxicosis. CASE SUMMARY: A 3-year-old female neutered mixed breed dog initially presented with neurological signs suspected to be secondary to LDX toxicosis. The dog was treated as typical for amphetamine toxicoses but developed severe respiratory and cardiovascular signs throughout their hospitalization. The progression of the cardiopulmonary signs led to cardiopulmonary arrest, for which CPR was unsuccessful. Postmortem examination exhibited severe hemorrhage throughout multiple organ systems. Toxicology testing confirmed the presence of unaltered LDX and its metabolite, amphetamine. NEW OR UNIQUE INFORMATION PROVIDED: This is the first case report documenting a severe progression of clinical signs and postmortem examination findings in a case of confirmed LDX toxicosis in a dog. Although the patient did not survive treatment, postmortem examination and microscopic evaluation of tissues allowed visualization of the extent of systemic pathophysiology. With prompt treatment, the prognosis of amphetamine toxicosis in dogs is generally considered good; however, this case report demonstrates a severe case in which even prompt and appropriate treatment did not prevent mortality. This suggests a need to establish negative prognostic indicators for which to monitor in cases of amphetamine toxicosis. Finally, this report is also unique in the fact that the LDX toxicosis was confirmed using a toxicological analysis technique not previously described clinically in dogs.

Neurobiological basis of reinforcement-based decision making in adults with ADHD treated with lisdexamfetamine dimesylate: Preliminary findings and implications for mechanisms influencing clinical improvement.

BACKGROUND: ADHD is often described as a disorder of altered reward sensitivity, yet few studies have examined the extent to which: (i) treatments for ADHD impact reward-related mechanisms; and (ii) changes in the reward system are associated with clinical improvement. This study addresses these issues - examining the extent to which clinical improvement following lisdexamfetamine (LDX) treatment is associated with changes in brain reward system activation. METHODS: Twenty adults (M = 11, 55%, F = 9, 45%), ages 19-52 (M = 33.9, SD = 10.0) with ADHD participated in a randomized cross-over study with lisdexamfetamine (LDX) and placebo (PB). Changes in brain activation were assessed during functional magnetic resonance (fMRI) scans: after receiving 3-5 weeks of treatment with LDX and 3-5 weeks of no drug/PB. fMRI contrasts were derived from the passive-avoidance (PA) learning task, which assessed reward-related learning using computational variables. We analyzed the following conditions: the Choice-Phase, modulated by the expected value (EV; i.e., object-choose and object-reject), and the Feedback-Phase, modulated by the prediction error (PE; i.e., reward and punish). Clinical symptom severity was assessed via interview with the ADHD-Rating Scale (ADHD-RS-IV). To address the primary objective, we performed group-level mass-univariate regression analyses between LDX and PB of percent change of the ADHD-RS total scores and the four contrast images under the Choice- and Feedback-conditions. Significance was set at a whole-brain voxel-wise threshold of p < 0.05 with family-wise error (FWE) correction and an extent (cluster) threshold of 50 contiguous voxels. RESULTS: Improvement in ADHD symptoms with LDX was accompanied by significantly increased activation in a series of brain regions previously implicated in reinforcement processing in the choice and feedback conditions (e.g., left caudate and putamen, right orbitofrontal cortex, left middle frontal, superior frontal, and precentral gyri). CONCLUSIONS: These findings, while preliminary, are the first to show that ADHD symptom improvement with stimulant treatment is associated with increased responsiveness of brain systems engaged in reward processing. Results support the hypothesis that LDX treatment may restore balance to dysfunction (e.g., hypoactivation) within the brain reward circuitry in adults with ADHD. Trial RegistrationClinicaltrials.gov Identifier: NCT01924429.

Lisdexamphetamine versus methylphenidate for paediatric patients with attention-deficit hyperactivity disorder and type 1 diabetes (LAMAinDiab): protocol for a multicentre, randomised cross-over clinical trial in an outpatient telemedicine-supported setting.

INTRODUCTION: Attention deficit hyperactivity disorder (ADHD) affects 5%-10% of paediatric population and is reportedly more common in children with type 1 diabetes (T1D), exacerbating its clinical course. Proper treatment of ADHD in such patients may thus provide neurological and metabolic benefits. To test this, we designed a non-commercial second phase clinical trial comparing the impact of different pharmacological interventions for ADHD in children with T1D. METHODS AND ANALYSIS: This is a multicentre, randomised, open-label, cross-over clinical trial in children and adolescents with ADHD and T1D. The trial will be conducted in four reference paediatric diabetes centres in Poland. Over 36 months, eligible patients with both T1D and ADHD (aged 8-16.5 years, T1D duration >1 year) will be offered participation. Patients' guardians will undergo online once-weekly training sessions behaviour management for 10 weeks. Afterward, children will be randomised to methylphenidate (long-release capsule, doses 18-36-54 mg) versus lisdexamphetamine (LDX, 30-50-70 mg). Pharmacotherapy will continue for 6 months before switching to alternative medication. Throughout the trial, the participants will be evaluated every 3 months by their diabetologist and online psychological assessments. The primary endpoint (ADHD symptom severity, Conners 3.0 questionnaire) will be assessed by a blinded investigator. Secondary endpoints will include HbA1c, continuous glucose monitoring indices and quality-of-life (PedsQL). ETHICS AND DISSEMINATION: The trial is approved by Bioethical Committee at Medical University of Lodz and Polish regulatory agency (RNN/142/22/KE, UR/DBL/D/263/2022). The results will be communicated to the research and clinical community, and Polish agencies responsible for healthcare policy. Patient organisations focused on paediatric T1D will be notified by a consortium member. We hope to use the trial's results to promote collaboration between mental health professionals and diabetes teams, evaluate the economic feasibility of using LDX in patients with both diseases and the long run improve ADHD treatment in children with T1D. TRIAL REGISTRATION NUMBERS: EU Clinical Trials Register (EU-CTR, 2022-001906-24) and NCT05957055.

Amphetamines Improve the Motivation to Invest Effort in Attention-Deficit/Hyperactivity Disorder.

Prevailing frameworks propose that a key feature of attention-deficit/hyperactivity disorder (ADHD) is lower motivation. An important component of motivation is the willingness to engage in cognitively or physically effortful behavior. However, the degree to which effort sensitivity is impaired in ADHD has rarely been tested, and the efficacy of stimulant medication in ameliorating any such impairments is unclear. Here, we tested 20 individuals with ADHD (11 males, 9 females) who were managed with amphetamine-based medication (dexamfetamine, lisdexamfetamine), and 24 controls (8 males, 16 females). Individuals with ADHD were tested over two counterbalanced sessions, ON and OFF their usual amphetamine-based medication. In each session, participants performed an effort-based decision-making task, in which they were required to choose how much cognitive or physical effort they were willing to engage in return for reward. Our results revealed three main findings. First, individuals with ADHD had lower motivation relative to controls to invest effort in both the cognitive and physical domains. Second, amphetamine increased motivation uniformly across both domains. Finally, the net effect of amphetamine treatment was to mostly restore motivation across both domains of effort relative to healthy controls. These data provide clear evidence for a heightened sensitivity to both cognitive and physical effort in ADHD, and reveal the efficacy of amphetamine-based drugs in restoring effort sensitivity to levels similar to controls. These findings confirm the existence of reduced motivational drive in ADHD, and more broadly provide direct causal evidence for a domain-general role of catecholamines in motivating effortful behavior.SIGNIFICANCE STATEMENT A core feature of attention-deficit/hyperactivity disorder (ADHD) is thought to be a heightened aversion to effort. Surprisingly, however, the degree to which effort sensitivity is impaired in ADHD has rarely been tested. More broadly, the relative efficacy of catecholamines in motivating the investment of cognitive and physical effort is unclear. We tested 20 individuals with ADHD ON and OFF amphetamines, and compared their behavior on an effort-based decision-making task to 24 controls. When tested OFF medication, the ADHD group was less cognitively and physically motivated than controls. However, amphetamines led to a comparable increase in motivation across both domains. This demonstrates the efficacy of catecholamines in facilitating domain-general effort, and highlights the broader potential of such drugs to treat disorders of motivation.

Efficacy, safety, and tolerability of nivasorexant in adults with binge-eating disorder: A randomized, Phase II proof of concept trial.

OBJECTIVE: This Phase II, placebo-controlled, double-blind study investigated the efficacy, safety, and tolerability of nivasorexant in the treatment of adults with moderate to severe binge-eating disorder (BED). METHODS: Adults meeting the DSM-5 BED criteria were randomized 1:1 to placebo or nivasorexant (100 mg b.i.d.). The primary endpoint was the change from baseline to Week 12 in the number of binge eating (BE) days per week. Exploratory efficacy endpoints included cessation of BE in the last 4 weeks of treatment; and change from baseline to Week 12 in the number of BE episodes/week, the clinician global impression (CGI) of change, the Yale-Brown Obsessive-Compulsive Scale modified for BE, and the Hamilton rating scale for depression (HAMD-17). Key safety outcomes included treatment-emergent adverse events (TEAEs) and adverse events of special interest (i.e., somnolence and fatigue). RESULTS: Sixty-eight participants were randomized to each treatment arm. The change from baseline to Week 12 in the number of BE days/week was the same for placebo (least squares mean [LSM]: -2.93) and nivasorexant (LSM: -2.93), with no difference between the treatment groups (LSM difference = .000 [95% confidence interval (CI): -.69, .69], p = .9992). Furthermore, no differences between treatment groups were observed in the exploratory efficacy endpoints. Nivasorexant was well tolerated; the overall incidence of TEAEs was balanced between treatment groups, and the frequency of somnolence and fatigue in the nivasorexant group were similar to placebo. DISCUSSION: In this proof-of-concept study, 100 mg b.i.d. nivasorexant did not improve BE in adults with moderate to severe BED. PUBLIC SIGNIFICANCE: The results of this Phase II study indicate that nivasorexant was well tolerated in adults with BED, but did not improve binge eating behavior over placebo. Further research is needed to improve our understanding of the role of the orexin-1 receptor in BED.

Epidemiology, Treatment Patterns, Comorbidities, and Concomitant Medication in Patients with ADHD in Sweden: A Registry-Based Study (2018-2021).

OBJECTIVE: To evaluate treatment patterns for ADHD in Sweden. METHOD: Observational retrospective study of patients with ADHD from the Swedish National Patient Register and Prescribed Drug Register, 2018 to 2021. Cross-sectional analyses included incidence, prevalence, and psychiatric comorbidities. Longitudinal analyses (newly diagnosed patients) included medication, treatment lines, duration, time-to-treatment initiation, and switching. RESULTS: Of 243,790 patients, 84.5% received an ADHD medication. Psychiatric comorbidities were common, particularly autism among children, and depression in adults. Most frequent first-/second-line treatments were methylphenidate (MPH; 81.6%) and lisdexamfetamine dimesylate (LDX; 46.0%), respectively. In the second-line, LDX was most frequently prescribed (46.0%), followed by MPH (34.9%), then atomoxetine (7.7%). Median treatment duration was longest for LDX (10.4 months), followed by amphetamine (9.1 months). CONCLUSION: This nationwide registry study provides real-life insights into the current epidemiology of ADHD and the changing treatment landscape for patients in Sweden.

Real-World Efficacy and Safety of Extended-Release Methylphenidate (PRC-063) in the Treatment of ADHD in Pediatric and Adult Subjects: Results of a Phase IV Multicenter Comparison With Lisdexamfetamine Dimesylate.

OBJECTIVE: To evaluate the real-world efficacy, safety, and functional outcomes of PRC-063 (multilayer-release methylphenidate) versus lisdexamfetamine (LDX) in ADHD subjects in a phase IV, open-label study. METHOD: The primary endpoint was the change in the ADHD-DSM-5 Rating Scale (ADHD-5-RS) total score from baseline to Month 4. Secondary endpoints included a non-inferiority comparison between PRC-063 and LDX and measures of functioning and evening behavior. RESULTS: One hundred forty-three pediatric and 112 adult subjects were enrolled. Mean ADHD-5-RS scores (standard deviation) were reduced in pediatric (-16.6 [10.4]) and adult (-14.8 [10.6]) subjects treated with PRC-063 (p < .001). PRC-063 was non-inferior to LDX in the pediatric population but not in the adult population. Significant improvements were demonstrated in quality of life and functionality. Both medications were well-tolerated; more adverse events led to study discontinuation in pediatric subjects treated with LDX versus PRC-063. CONCLUSION: PRC-063 and LDX significantly improved ADHD symptomatology and functioning and were well-tolerated.

Risk of Major Malformations in Infants After First-Trimester Exposure to Stimulants: Results From the Massachusetts General Hospital National Pregnancy Registry for Psychiatric Medications.

PURPOSE/BACKGROUND: The prevalence of attention-deficit/hyperactivity disorder in adult females is 3% to 4%. Attention-deficit/hyperactivity disorder is highly comorbid with other psychiatric disorders such as mood, anxiety, and substance use disorders. For reproductive-aged women, the treatment of attention-deficit/hyperactivity disorder with stimulant medications may be considered during pregnancy or breastfeeding, although historically, data are lacking to inform these decisions. The aim of this investigation was to determine the risk of major malformations in infants after first-trimester prescription stimulant exposure in a small but rigorously characterized sample. METHODS/PROCEDURES: The Massachusetts General Hospital National Pregnancy Registry for Psychiatric Medications systematically ascertains information from pregnant females including demographic information, medical and psychiatric history, use of prescription medications, and other information relevant to fetal outcomes. Participants provide verbal informed consent and are interviewed twice during gestation and again at approximately 3 months postpartum. The primary outcome of interest is the presence of a major malformation identified within 6 months after birth. Redacted cases of major malformations are reviewed by a dysmorphologist blinded to medication exposure. FINDINGS/RESULTS: A total of N = 1988 women were eligible for this analysis, including the following exposures: n = 173 to mixed amphetamine salts; n = 40 to lisdexamfetamine; n = 45 to methylphenidate; n = 3 to dexmethylphenidate; and n = 1755 controls. The odds ratio of a major malformation among infants after first-trimester exposure to any stimulant was 0.39 (95% confidence interval, 0.09-1.61) compared with controls. There were no major malformations observed in infants exposed to lisdexamfetamine, methylphenidate, or dexmethylphenidate. IMPLICATIONS/CONCLUSIONS: Although preliminary, this analysis from an ongoing pregnancy registry provides reassurance that these stimulants do not appear to have major teratogenic effects. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01246765 .

[Psychostimulants: An Overview].

Treatment of narcolepsy is based on the need to regulate life rhythms. Psychostimulants such as modafinil, methylphenidate-immediate release, and pemoline are used to treat hypersomnia. A psychosocial approach is considered the mainstay of treatment for attention-deficit/hyperactivity disorder (ADHD), and medication is used to treat moderate or severe ADHD symptoms. Two of the four drugs approved in Japan for ADHD therapy (osmotic-release oral system methylphenidate and lisdexamfetamine dimesylate) are psychostimulants, which are administered via the ADHD proper distribution management system.

Pharmacologic Management of Cognitive Disengagement Syndrome (CDS) and Implications for Attention-Deficit/Hyperactivity Disorder (ADHD) Treatment: Emerging Treatments and Recommendations for Future Research.

Although the study of cognitive disengagement syndrome (CDS; previously called sluggish cognitive tempo) first emerged in the 1980s, very little is known about treating CDS or its impact on evidence-based interventions for attention-deficit/hyperactivity disorder (ADHD) with which it frequently co-occurs. The objective of this leading article was to investigate the existing evidence on medication treatment and CDS, including studies that have examined CDS response to medication and CDS as a moderator of ADHD treatment response. A total of seven studies were identified. At present, the limited existing literature suggests that psychostimulants such as methylphenidate and lisdexamfetamine, as well as atomoxetine, may improve CDS symptoms, although replication and research on related medications is needed. However, there are indications that CDS symptoms may predict a reduced response to methylphenidate in children with ADHD. Although untested, research on the neurobiological, neuropsychological, and behavioral correlates of CDS point to a possible benefit of other ADHD medications (e.g., guanfacine), medications that treat narcolepsy (e.g., modafinil), and medications traditionally used to treat depression and anxiety (e.g., viloxazine, bupropion, fluvoxamine), some of which have also recently been used in ADHD management. The article concludes with recommendations for future research on pharmacologic treatment and CDS.

Do ADHD Treatments Improve Executive Behavior Beyond Core ADHD Symptoms in Adults? Evidence From Systematic Analysis of Clinical Trials.

We sought to understand the effect of current treatments for attention deficit hyperactivity disorder (ADHD) on executive functioning deficits, which are often comorbid with ADHD, via a systematic analysis of adult ADHD treatment studies evaluating change in behavioral measures beyond the core symptoms of Diagnostic and Statistical Manual of Mental Disorders ADHD. The standardized mean difference for behavioral measures of executive functioning was determined from controlled trials of adults with ADHD and compared with effects on core ADHD symptoms. Several studies of atomoxetine revealed small to large standardized mean differences. Nonreplicated studies revealed small to medium effects for triple-bead mixed amphetamine salts, lisdexamfetamine, and forms of cognitive behavioral therapy. Proportional effect versus core ADHD symptoms ranged from 0.78 to 1.16 for atomoxetine, and from 0.65 to 1.44 across all the studies. ADHD treatments have effects on executive functioning behavior beyond core ADHD symptoms in adults. Clinicians can measure and treat this morbidity using available clinical tools.

Prevalence trends and individual patterns of ADHD medication use in pregnancy in Norway and Sweden, 2010-2019.

PURPOSE: This study aimed to describe recent trends in ADHD medication use in pregnancy in Norway and Sweden, including prevalence, individual characteristics, and patterns of use. METHODS: We studied ADHD medication use (amphetamine, dexamphetamine, methylphenidate, atomoxetine, lisdexamfetamine, guanfacine) by year and age in pregnancies from 2010 to 2019 identified from the medical birth registers (gestational age ≥ 22 weeks) linked to prescribed drug registers (Norway, N = 577,116; Sweden, N = 1,118,988). We compared characteristics of those who used any ADHD medication in pregnancy to no use in pregnancy. Discontinuation was defined as no use after first trimester. RESULTS: ADHD medication use increased from 2010 to 2019 by 3.0 users per 1000 pregnancies in Norway (from 2.5 to 5.5/1000) and by 6.3 per 1000 in Sweden (from 1.6 to 7.9/1000), mainly driven by methylphenidate and since 2015 by lisdexamfetamine. Medication use has increased among pregnant individuals of all age groups, with higher use among the youngest. Pregnant individuals who used ADHD medication were less likely to be married/cohabiting, more likely be nulliparous and to smoke. They had particularly high use of co-medication with antidepressants, anxiolytics/hypnotics, and opioids: 42% in Norway and 65% in Sweden used at least one additional class of psychotropic medication. Most individuals discontinued ADHD medication in pregnancy (85% Norway, 78% Sweden). CONCLUSION: ADHD medication use during pregnancy increased in Norway and Sweden in the last decade. However, discontinuation rates during pregnancy were high. Those who used ADHD medication had more risk factors for pregnancy complications including low parity, smoking, and other psychotropic drug use.

The Use of Brexpiprazole Combined With a Stimulant in Adults With Treatment-Resistant Attention-Deficit/Hyperactivity Disorder.

BACKGROUND: This is the first controlled pharmacologic study in either adults or children with uncomplicated, treatment-resistant attention-deficit/hyperactivity disorder (ADHD). This study augmented stimulant therapy with the atypical antipsychotic brexpiprazole. The Food and Drug Administration preapproved primary outcome measure (Conners' Adult ADHD Rating Scale [CAARS]) showed no drug-placebo differences. Often studies showing no efficacy on the prestudy, defined primary outcome variable go unpublished. While this is decried, publishing studies with equivocal results remains rare. This reanalysis highlights trends in secondary measures having implications for treatment and research regarding treatment resistant ADHD. METHODS: Initially, 559 stimulant-naive and 174 prior stimulant nonresponders received methylphenidate osmotic-release oral system, dexmethylphenidate hydrochloride, lisdexamfetamine, or mixed amphetamine salts. After 5 weeks, 168 stimulant-naive patients and 68 prior stimulant nonresponders who failed treatment were randomized to brexpiprazole or placebo in a 2:1 ratio while the remaining were on the stimulant. Outcome was measured with the CAARS, Montgomery-Asberg Depression Rating Scale, Beck Depression Inventory, Clinical Global Impression, and the Wender-Reimherr Adult Attention Deficit Disorder Scale (WRAADDS). The WRAADDS contains 2 factors: attention and emotional dysregulation. RESULTS: Stimulant-naive patients showed no improvement with adjunctive brexpiprazole. Prior stimulant nonresponders displayed no brexpiprazole effect on the CAARS, Montgomery-Asberg Depression Rating Scale, or Beck Depression Inventory. In contrast, the WRAADDS detected a trend in treatment benefit, primarily through emotional dysregulation symptoms. Adverse effects on brexpiprazole and placebo were equivalent. CONCLUSIONS: Brexpiprazole might be effective in ADHD adults who are nonresponders to 2 or more stimulants. Future trials in treatment-resistant ADHD should use a 1:1 randomization and use a measure of ADHD symptoms that includes emotional dysregulation.

Do Treatments for Adult ADHD Improve Emotional Behavior? A Systematic Review and Analysis.

OBJECTIVE: Dysregulated emotional behavior occurs often in adults with ADHD. Analysis of clinical trials may guide clinical intervention and future research. METHOD: Controlled trials of adult ADHD measuring emotional behavior were included if another study offered a comparable analysis of the same treatment method. Standardized Mean Difference (SMD) of effects were calculated, and the size of effects for emotional and non-emotional ADHD behavior were compared. RESULTS: 13 out of 14 studies of methylphenidate, atomoxetine, and lisdexamfetamine demonstrated significant improvement in emotional behavior measures, with small to high SMDs. The proportional effect on emotional versus non-emotional behavior ranged from 46% to 110% for methylphenidate, 56% to 129% for atomoxetine, and 36% to 96% for lisdexamfetamine. CONCLUSION: Psychopharmacological treatments for ADHD are likely to improve emotional behavior, and available scales are sensitive to these effects. Studies dedicated to treatment of this domain of function can further refine clinical approaches.

Causal effects of psychostimulants on neural connectivity: a mechanistic, randomized clinical trial.

BACKGROUND: Psychostimulants are frequently used to treat attention-deficit/hyperactivity disorder (ADHD), but side effects are common leading to many patients discontinuing treatment. Identifying neural mechanisms by which psychostimulants attenuate symptoms may guide the development of more refined and tolerable therapeutics. METHODS: We conducted a 12-week, randomized, placebo-controlled trial (RCT) of a long-acting amphetamine, lisdexamfetamine (LDEX), in patients with ADHD, ages 6-25 years old. Of the 58 participants who participated in the RCT, 49 completed pre- and post-RCT magnetic resonance imaging scanning with adequate data quality. Healthy controls (HCs; n = 46) were included for comparison. Treatment effects on striatal and thalamic functional connectivity (FC) were identified using static (time-averaged) and dynamic (time-varying) measures and then correlated with symptom improvement. Analyses were repeated in independent samples from the Adolescent Brain Cognitive Development study (n = 103) and the ADHD-200 Consortium (n = 213). RESULTS: In 49 participants (25 LDEX; 24 Placebo), LDEX increased static and decreased dynamic FC (DFC). However, only DFC was associated with the therapeutic effects of LDEX. Additionally, at baseline, DFC was elevated in unmedicated-ADHD participants relative to HCs. Independent samples yielded similar findings - ADHD was associated with increased DFC, and psychostimulants with reduced DFC. Static FC findings were inconsistent across samples. CONCLUSIONS: Changes in dynamic, but not static, FC were associated with the therapeutic effects of psychostimulants. While prior research has focused on static FC, DFC may offer a more reliable target for new ADHD interventions aimed at stabilizing network dynamics, though this needs confirmation with subsequent investigations.

The potential role of stimulants in treating eating disorders.

BACKGROUND: Many individuals with eating disorders remain symptomatic after a course of psychotherapy and pharmacotherapy; therefore, the development of innovative treatments is essential. METHOD: To learn more about the current evidence for treating eating disorders with stimulants, we searched for original articles and reviews published up to April 29, 2021 in PubMed and MEDLINE using the following search terms: eating disorders, anorexia, bulimia, binge eating, stimulants, amphetamine, lisdexamfetamine, methylphenidate, and phentermine. RESULTS: We propose that stimulant medications represent a novel avenue for future research based on the following: (a) the relationship between eating disorders and attention deficit/hyperactivity disorder (ADHD); (b) a neurobiological rationale; and (c) the current (but limited) evidence for stimulants as treatments for some eating disorders. Despite the possible benefits of such medications, there are also risks to consider such as medication misuse, adverse cardiovascular events, and reduction of appetite and pathological weight loss. With those risks in mind, we propose several directions for future research including: (a) randomized controlled trials to study stimulant treatment in those with bulimia nervosa (with guidance on strategies to mitigate risk); (b) examining stimulant treatment in conjunction with psychotherapy; (c) investigating the impact of stimulants on "loss of control" eating in youth with ADHD; and (d) exploring relevant neurobiological mechanisms. We also propose specific directions for exploring mediators and moderators in future clinical trials. DISCUSSION: Although this line of investigation may be viewed as controversial by some in the field, we believe that the topic warrants careful consideration for future research.

Prospects for new drugs to treat binge-eating disorder: Insights from psychopathology and neuropharmacology.

BACKGROUND: Binge-eating disorder (BED) is a common psychiatric condition with adverse psychological and metabolic consequences. Lisdexamfetamine (LDX) is the only approved BED drug treatment. New drugs to treat BED are urgently needed. METHODS: A comprehensive review of published psychopathological, pharmacological and clinical findings. RESULTS: The evidence supports the hypothesis that BED is an impulse control disorder with similarities to ADHD, including responsiveness to catecholaminergic drugs, for example LDX and dasotraline. The target product profile (TPP) of the ideal BED drug combines treating the psychopathological drivers of the disorder with an independent weight-loss effect. Drugs with proven efficacy in BED have a common pharmacology; they potentiate central noradrenergic and dopaminergic neurotransmission. Because of the overlap between pharmacotherapy in attention deficit hyperactivity disorder (ADHD) and BED, drug-candidates from diverse pharmacological classes, which have already failed in ADHD would also be predicted to fail if tested in BED. The failure in BED trials of drugs with diverse pharmacological mechanisms indicates many possible avenues for drug discovery can probably be discounted. CONCLUSIONS: (1) The efficacy of drugs for BED is dependent on reducing its core psychopathologies of impulsivity, compulsivity and perseveration and by increasing cognitive control of eating. (2) The analysis revealed a large number of pharmacological mechanisms are unlikely to be productive in the search for effective new BED drugs. (3) The most promising areas for new treatments for BED are drugs, which augment noradrenergic and dopaminergic neurotransmission and/or those which are effective in ADHD.