A matching-adjusted indirect comparison of centanafadine versus lisdexamfetamine, methylphenidate and atomoxetine in adults with attention-deficit/hyperactivity disorder: long-term safety and efficacy.

Aim: To compare long-term safety and efficacy outcomes of centanafadine versus lisdexamfetamine dimesylate (lisdexamfetamine), methylphenidate hydrochloride (methylphenidate) and atomoxetine hydrochloride (atomoxetine), respectively, in adults with attention-deficit/hyperactivity disorder (ADHD) using matching-adjusted indirect comparisons (MAICs). Patients & methods: Patient-level data from a centanafadine trial (NCT03605849) and published aggregate data from a lisdexamfetamine trial (NCT00337285), a methylphenidate trial (NCT00326300) and an atomoxetine trial (NCT00190736) were used. Patient characteristics were matched in each comparison using propensity score weighting. Study outcomes were assessed up to 52 weeks and included safety (rates of adverse events [AEs]) and efficacy (mean change from baseline in the Adult ADHD Investigator Symptom Rating Scale [AISRS] or ADHD Rating Scale [ADHD-RS] score). Results: In all comparisons of matched populations, risks of AEs were statistically significantly lower with centanafadine or non-different between centanafadine and comparator; the largest differences in AE rates included upper respiratory tract infection (risk difference in percentage points: 18.75), insomnia (12.47) and dry mouth (12.33) versus lisdexamfetamine; decreased appetite (20.25), headache (18.53) and insomnia (12.65) versus methylphenidate; and nausea (26.18), dry mouth (25.07) and fatigue (13.95) versus atomoxetine (all p < 0.05). Centanafadine had a smaller reduction in the AISRS/ADHD-RS score versus lisdexamfetamine (6.15-point difference; p < 0.05) and no statistically significant difference in the change in AISRS score versus methylphenidate (1.75-point difference; p = 0.13) and versus atomoxetine (1.60-point difference; p = 0.21). Conclusion: At up to 52 weeks, centanafadine showed significantly lower incidence of several AEs than lisdexamfetamine, methylphenidate and atomoxetine; efficacy was lower than lisdexamfetamine and non-different from methylphenidate and atomoxetine.

Pharmacological Modulation of Cognitive Test Solution in Mice of Two Genotypes.

Mice of two strains selected for successful solution of "object permanence" test and for lack of such solution demonstrated the differential reaction to injections of two drugs. The effects of injections of atomoxetine. which blocks the noradrenaline reuptake, and of 'non-benzodiazepine" anxiolytic afobazol was different. The success of solutions increased in mice selected for this test "non-solution": and decreased or was inefficient in mice, selected for successful solution of object permanence cognitive test.

Evaluation of SLC6A2 and CYP2D6 polymorphisms' effects on atomoxetine treatment in attention deficit and hyperactivity disorder.

BACKGROUND: There is insufficient replicated data to establish a relationship between the polymorphisms of SLC6A2 and CYP2D6 and the treatment responses of atomoxetine (ATX) in ADHD. We focused on evaluating the effect of top-line single nucleotide polymorphisms (SNPs) in SLC6A2 and CYP2D6 on the ATX treatment response in attention deficit and hyperactivity disorder (ADHD). METHODS: Of 160 patient records, 34 patients who met the inclusion criteria were evaluated to determine the relationship between genotypes of ten SNPs (six of SLC6A2 and four of CYP2D6) and ATX treatment response. Additionally, the connection between SNPs of CYP2D6 and the severity of side effects associated with ATX was analyzed in 37 patients, including the 34 study patients, and three patients discontinued because of ATX-dependent side effects. RESULTS: All six polymorphisms we studied in SLC6A2 were associated with the treatment response of ATX. Clinical improvement in oppositional defiant disorder symptoms of patients with ADHD was only observed in carriers of the homozygous "C" allele of rs3785143 (podd = 0.026). We detected an association between higher CGI-side-effect severity scores and the "TT" genotype of rs1065852 polymorphism in CYP2D6 (p = 0.043). CONCLUSIONS: The findings of this study suggest that genotypes of polymorphisms within the SLC6A2 and CYP2D6 may play an influential role in treatment response or the severity of side effects associated with ATX in ADHD patients.

Attenuated responses to attention-modulating drugs in the neuroligin-3R451C mouse model of autism.

Attention deficits are frequently reported within the clinical autism population. Despite not being a core diagnostic feature, some aetiological theories place atypical attention at the centre of autism development. Drugs used to treat attention dysfunction are therefore increasingly prescribed to autistic patients, though currently off-label with uncertain efficacy. We utilised a rodent-translated touchscreen test of sustained attention in mice carrying an autism-associated R451C mutation in the neuroligin-3 gene (Nlgn3R451C). In doing so, we replicated their cautious but accurate response profile and probed it using two widely prescribed attention-modulating drugs: methylphenidate (MPH) and atomoxetine (ATO). In wild-type mice, acute administration of MPH (3 mg/kg) promoted impulsive responding at the expense of accuracy, while ATO (3 mg/kg) broadly reduced impulsive responding. These drug effects were absent in Nlgn3R451C mice, other than a small reduction in blank touches to the screen following ATO administration. The absence of drug effects in Nlgn3R451C mice likely arises from their altered behavioural baseline and underlying neurobiology, highlighting caveats to the use of classic attention-modulating drugs across disorders and autism subsets. It further suggests that altered dopaminergic and/or norepinephrinergic systems may drive behavioural differences in the Nlgn3R451C mouse model of autism, supporting further targeted investigation.

Development and In vivo Evaluation of Atomoxetine Hydrochloride ODMTs in a Nicotine-induced Attention Deficit Hyperactivity Disorder (ADHD) Model in Rats.

The current study aimed to evaluate the efficacy of orally administered rapid mini-tablets containing atomoxetine hydrochloride (ODMT) relative to the conventional capsule formulation of atomoxetine hydrochloride (ATO). To mask the bitter taste of ATO and render it more palatable for pediatric administration in individuals with Attention Deficit Hyperactivity Disorder (ADHD), an inclusion complex of ATO with ß-cyclodextrin (ß-CD) was synthesized. The ODMT and conventional capsule ATO formulations were administered orally to a cohort of ADHD rat pups born to nicotine-exposed dams, facilitating an in vivo efficacy assessment. Behavioral assays, including the open field test, novel object recognition test, and Barnes maze test, were conducted pre- and post-administration of the therapeutics. The outcomes suggested that the ODMT formulation, incorporating ATO-ß-CD inclusion complexes, shows promise as a viable alternative to the capsule form of ATO. Conclusively, the preparation of the ATO-ß-CD complexes and ODMTs leveraged a factorial experimental design, with the animal model being subjected to nicotine-induced hyperactivity to provide a unique evaluative framework for the ODMT formulation under development.

Pharmacological Elevation of Catecholamine Levels Improves Perceptual Decisions, But Not Metacognitive Insight.

Perceptual decisions are often accompanied by a feeling of decision confidence. Where the parietal cortex is known for its crucial role in shaping such perceptual decisions, metacognitive evaluations are thought to additionally rely on the (pre)frontal cortex. Because of this supposed neural differentiation between these processes, perceptual and metacognitive decisions may be divergently affected by changes in internal (e.g., attention, arousal) and external (e.g., task and environmental demands) factors. Although intriguing, causal evidence for this hypothesis remains scarce. Here, we investigated the causal effect of two neuromodulatory systems on behavioral and neural measures of perceptual and metacognitive decision-making. Specifically, we pharmacologically elevated levels of catecholamines (with atomoxetine) and acetylcholine (with donepezil) in healthy adult human participants performing a visual discrimination task in which we gauged decision confidence, while electroencephalography was measured. Where cholinergic effects were not robust, catecholaminergic enhancement improved perceptual sensitivity, while at the same time leaving metacognitive sensitivity unaffected. Neurally, catecholaminergic elevation did not affect sensory representations of task-relevant visual stimuli but instead enhanced well-known decision signals measured over the centroparietal cortex, reflecting the accumulation of sensory evidence over time. Crucially, catecholaminergic enhancement concurrently impoverished neural markers measured over the frontal cortex linked to the formation of metacognitive evaluations. Enhanced catecholaminergic neuromodulation thus improves perceptual but not metacognitive decision-making.

Profiling deutetrabenazine extended-release tablets for tardive dyskinesia and chorea associated with Huntington's disease.

INTRODUCTION: Tardive dyskinesia (TD) and Huntington's disease (HD)-associated chorea are persistent and disabling hyperkinetic disorders that can be treated with vesicular monoamine transporter type 2 (VMAT2) inhibitors, including the recently approved once-daily (QD) formulation of deutetrabenazine (DTBZ ER). While its efficacy and safety profile have not been directly investigated, currently available data confirms bioequivalence and similar bioavailability to the twice-daily formulation (DTBZ BID). AREAS COVERED: The authors briefly review the pivotal trials establishing efficacy of DTBZ for TD and HD-associated chorea, the pharmacokinetic data for bioequivalence between QD and BID dosing of DTBZ, as well as dose proportionality evidence, titration recommendations, and safety profile for DTBZ ER. EXPERT OPINION: Long-term data show that DTBZ is efficacious and well tolerated for the treatment of TD and HD-associated chorea. DTBZ ER likely demonstrates therapeutic equivalence with no new safety signals. Due to the lack of comparative clinical trial data, no evidence-based recommendation about choice of VMAT2 inhibitor or switching between VMAT2 inhibitors can be made about best practice. Ultimately, QD dosing may offer the chance of improved medication adherence, an important consideration in patients with complex treatment regimens and/or patients with cognitive decline.

Assessment of centanafadine in adults with attention-deficit/hyperactivity disorder: A matching-adjusted indirect comparison vs lisdexamfetamine dimesylate, atomoxetine hydrochloride, and viloxazine extended-release.

BACKGROUND: Head-to-head trials comparing centanafadine, an investigational therapy for adults with attention-deficit/hyperactivity disorder (ADHD), with other treatment options are lacking. OBJECTIVE: To compare safety and efficacy outcomes of centanafadine sustained-release vs lisdexamfetamine dimesylate (lisdexamfetamine), atomoxetine hydrochloride (atomoxetine), and viloxazine extended-release (viloxazine ER), respectively, using matching-adjusted indirect comparison (MAIC). METHODS: This MAIC included patient-level data pooled from 2 centanafadine trials (NCT03605680 and NCT03605836) and published aggregate data from comparable trials of 3 comparators-lisdexamfetamine (NCT00334880), atomoxetine (NCT00190736), and viloxazine ER (NCT04016779)-in adult patients with ADHD. Propensity score weighting was used to match characteristics of individual patients from the centanafadine trials to aggregate baseline characteristics from the respective comparator trials. Safety outcomes were rates of adverse events for which information was available in the centanafadine and respective comparator trials. Efficacy outcome was mean change from baseline in the Adult ADHD Investigator Symptom Rating Scale (AISRS) score (ADHD Rating Scale [ADHD-RS] was used as proxy in the comparison with lisdexamfetamine). Anchored indirect comparisons were conducted across matched populations of the centanafadine and respective comparator trials. RESULTS: After matching, baseline characteristics in the centanafadine trials were the same as those in the respective comparator trials. Compared with lisdexamfetamine, centanafadine was associated with a significantly lower risk of lack of appetite (risk difference [RD] in percentage points: 23.42), dry mouth (19.27), insomnia (15.35), anxiety (5.21), nausea (4.90), feeling jittery (3.70), and diarrhea (3.47) (all P < 0.05) but a smaller reduction in the AISRS/ADHD-RS score (6.58-point difference; P < 0.05). Compared with atomoxetine, centanafadine was associated with a significantly lower risk of nausea (RD in percentage points: 18.64), dry mouth (17.44), fatigue (9.21), erectile dysfunction (6.76), lack of appetite (6.71), and urinary hesitation (5.84) (all P < 0.05) and no statistically significant difference in the change in AISRS score. Compared with viloxazine ER, centanafadine was associated with a significantly lower risk of fatigue (RD in percentage points: 11.07), insomnia (10.67), nausea (7.57), and constipation (4.63) (all P < 0.05) and no statistically significant difference in the change in AISRS score. CONCLUSIONS: In an anchored MAIC, centanafadine showed a significantly better short-term safety profile than lisdexamfetamine, atomoxetine, and viloxazine ER; efficacy was lower than with lisdexamfetamine and comparable (ie, nondifferent) with atomoxetine and viloxazine ER. This MAIC provides important insights on the relative safety and efficacy of common treatment options to help inform treatment decisions in adults with ADHD. Safety assessment was limited to rates of adverse events reported in both trials of a given comparison. STUDY REGISTRATION NUMBERS: NCT03605680, NCT03605836, NCT00334880, NCT00190736, and NCT04016779.

Adolescent stress differentially modifies dopamine and norepinephrine release in the medial prefrontal cortex of adult rats.

Adolescent stress (AS) has been associated with higher vulnerability to psychiatric disorders such as schizophrenia, depression, or drug dependence. Moreover, the alteration of brain catecholamine (CAT) transmission in the medial prefrontal cortex (mPFC) has been found to play a major role in the etiology of psychiatric disturbances. We investigated the effect of adolescent stress on CAT transmission in the mPFC of freely moving adult rats because of the importance of this area in the etiology of psychiatric disorders, and because CAT transmission is the target of a relevant group of drugs used in the therapy of depression and psychosis. We assessed basal dopamine (DA) and norepinephrine (NE) extracellular concentrations (output) by brain microdialysis in in the mPFC of adult rats that were exposed to chronic mild stress in adolescence. To ascertain the role of an altered release or reuptake, we stimulated DA and NE output by administering either different doses of amphetamine (0.5 and 1.0 mg / kg s.c.), which by a complex mechanism determines a dose dependent increase in the CAT output, or reboxetine (10 mg/kg i.p.), a selective NE reuptake inhibitor. The results showed the following: (i) basal DA output in AS rats was lower than in controls, while no difference in basal NE output was observed; (ii) amphetamine, dose dependently, stimulated DA and NE output to a greater extent in AS rats than in controls; (iii) reboxetine stimulated NE output to a greater extent in AS rats than in controls, while no difference in stimulated DA output was observed between the two groups. These results show that AS determines enduring effects on DA and NE transmission in the mPFC and might lead to the occurrence of psychiatric disorders or increase the vulnerability to drug addiction.

Current nonstimulant medications for adults with attention-deficit/hyperactivity disorder.

INTRODUCTION: Stimulants, including methylphenidate and amphetamines, are the first-line pharmacological treatment of ADHD in adults. However, in patients who do not respond or poorly tolerate stimulants, non-stimulant medications are usually recommended. AREAS COVERED: The authors provide a narrative review of the literature on non-stimulant treatments for adult ADHD, including controlled and observational clinical studies conducted on adult samples. Atomoxetine has been extensively studied and showed significant efficacy in treating adult ADHD. Issues related to dosing, treatment duration, safety, and use in the case of psychiatric comorbidity are summarized. Among other compounds indicated for ADHD in adults, antidepressants sharing at least a noradrenergic or dopaminergic component, including tricyclic compounds, bupropion, and viloxazine, have shown demonstratable efficacy. Evidence is also available for antihypertensives, particularly guanfacine, as well as memantine, metadoxine, and mood stabilizers, while negative findings have emerged for galantamine, antipsychotics, and cannabinoids. EXPERT OPINION: While according to clinical guidelines, atomoxetine may serve as the only second-line option in adults with ADHD, several other nonstimulant compounds may be effectively used in order to personalize treatment based on comorbid conditions and ADHD features. Nevertheless, further research is needed to identify and test more personalized treatment strategies for adults with ADHD.

Microstructural properties of attention-related white matter tracts are associated with the renewal effect of extinction.

The tendency to show the renewal effect of extinction appears as an intra-individually stable, reproducible processing strategy associated with differential patterns of BOLD activation in hippocampus, iFG and vmPFC, as well as differential resting-state functional connectivity between prefrontal regions and the dorsal attention network. Also, pharmacological modulations of the noradrenergic system that influence attentional processing have partially different effects upon individuals with (REN) and without (NoREN) a propensity for renewal. However, it is as yet unknown whether REN and NoREN individuals differ regarding microstructural properties in attention-related white matter (WM) regions, and whether such differences are related to noradrenergic processing. In this diffusion tensor imaging (DTI) analysis we investigated the relation between microstructural properties of attention-related WM tracts and ABA renewal propensity, under conditions of noradrenergic stimulation by means of the noradrenergic reuptake inhibitor atomoxetine, compared to placebo. Fractional anisotropy (FA) was higher in participants with noradrenergic stimulation (ATO) compared to placebo (PLAC), the effect was predominantly left-lateralized and based on the comparison of ATO REN and PLAC REN participants. In REN participants of both treatment groups, FA in several WM tracts showed a positive correlation with the ABA renewal level, suggesting higher renewal levels were associated with higher microstructural integrity. These findings point towards a relation between microstructural properties of attention-related WM tracts and the propensity for renewal that is not specifically dependent on noradrenergic processing.

Mining of neurological adverse events associated with valbenazine: A post-marketing analysis based on FDA adverse event reporting system.

PURPOSE: Valbenazine is commonly used to treat tardive dyskinesia, and we conducted a pharmacovigilance analysis using the Food and Drug Administration Adverse Event Reporting System (FAERS) to evaluate neurological safety signals associated with valbenazine. METHODS: Data was collected in FAERS from the second quarter of 2017 to the fourth quarter of 2023 for data cleaning. Neurological adverse event (AE) signals of valbenazine were mined by calculating reporting odds ratios (ROR), information component (IC) and empirical Bayesian geometric mean (EBGM). The serious and non-serious cases and signals were prioritized using a rating scale. RESULTS: The number of neurological AE reports where the primary suspect (PS) drug was 8981 for valbenazine. Significant AE signals were identified by the preferred term (PT) analysis for valbenazine, including somnolence (ROR 19.69), tremor (ROR 15.17), and tardive dyskinesia (ROR 236.91), among which 18 AEs were identified as new signals. Patient age (p < 0.009) and sex (p = 0.197) might be associated with an increased risk of neurological AE severity. Notably, the association between valbenazine and neurological disorders remained when stratified by sex, age, and reporter type. AE timing analysis was performed for the drug and four moderate clinical priority signals [i.e., somnolence, balance disorder, parkinsonism, and akathisia (priorities 7)], showing the same early failure type profiles. CONCLUSIONS: The increase in neurological safety signals is identified in the post-marketing research of valbenazine. Clinicians need to pay attention to not only common AEs but also be alert to new neurological AE signals when using valbenazine.

The role of adrenergic neurotransmitter reuptake inhibitors in the ADHD armamentarium.

INTRODUCTION: Adrenergic neurotransmitter reuptake inhibitors are gaining attention in treatment for attention-deficit hyperactivity disorder (ADHD). Due to their effects on norepinephrine, dopamine, and serotonin neurotransmission, they benefit both ADHD and comorbid disorders and have some other advantages including longer duration of action and fewer adverse effects compared to stimulants. There is continued interest in these agents with novel mechanisms of action in treatment of ADHD. AREAS COVERED: The authors conducted a PubMed literature search using the following key words: 'ADHD' AND 'adrenergic reuptake inhibitors' OR 'nonstimulants' OR 'atomoxetine' OR 'Viloxazine' OR 'Dasotraline' OR 'Centanafadine' OR 'PDC-1421' OR 'Reboxetine' OR 'Edivoxetine' OR 'Bupropion' OR 'Venlafaxine' OR 'Duloxetine.' They reviewed FDA fact sheets of available medications for safety/tolerability studies and reviewed published clinical studies of these medications for treatment of ADHD. EXPERT OPINION: Adrenergic neurotransmitter reuptake inhibitors fit the diverse needs of children and adolescents with ADHD with 1) poor tolerability to stimulants (e.g. due to growth suppression, insomnia, rebound irritability, co-morbid depression, anxiety and tic disorders, substance abuse or diversion concerns), 2) cardiac risks, and/or 3) need for extended duration of action. Their differences in receptor affinities and modulating effects support the unique benefits of individual agents.

Dispensing of attention-deficit hyperactivity disorder medications for adults in Aotearoa New Zealand.

AIM: To report dispensing trends for attention-deficit hyperactivity disorder (ADHD) in Aotearoa New Zealand, focussing on adults in order to highlight increasing demand for ADHD treatment by adults and to prompt discussion. METHOD: Demographic and dispensing data for ADHD were obtained from the Pharmaceutical Collection between the years 2006 and 2022. This was stratified according to child (<18 years) and adult (≥18 years) populations. Population dispensing rates for methylphenidate and atomoxetine were calculated. Key findings are reported to reveal demographic and dispensing trends for medication treated ADHD in Aotearoa New Zealand. RESULTS: More males are dispensed ADHD medication than females, although this is less evident for adults (54.8% male). Maori adults are dispensed ADHD medication at a lower rate (10.1%) than Maori children (22.9%). There was a 10-fold increase in dispensing of ADHD medication for adults compared to a three-fold increase for children over the study period. New dispensing for adults doubled between 2011 and 2022. CONCLUSION: Medication treatment for adult ADHD is increasing in Aotearoa New Zealand and includes treatment for persisting childhood ADHD and new diagnoses made in adulthood. Despite increases, dispensing rates for ADHD remain lower than prevalence estimates, suggesting a significant treatment gap. Addressing the treatment gap for ADHD may reduce negative effects of ADHD, but wider social influences should also be considered.

Medications for attention deficit hyperactivity disorder associated with increased risk of developing glaucoma.

BACKGROUND: Attention deficit hyperactivity disorder (ADHD) therapies including atomoxetine, methylphenidate, and amphetamines are some of the most prescribed medications in North America. Due to their sympathomimetic action, these drugs are contraindicated in patients with a history of angle closure glaucoma (ACG). This study aims to determine the risk of ACG and open angle glaucoma (OAG) among users of these treatments. METHODS: This is a retrospective cohort study with a case control analysis using the PharMetrics Plus Database (IQVIA, USA). We created a cohort of new users of atomoxetine, methylphenidate, and amphetamines and they were followed to the first diagnosis of (1) ACG or OAG; or (2) end of follow up. For each case, four age-matched controls were selected. A conditional logistic regression model was used to adjust for confounders and to calculate adjusted incidence-rate-ratios (aIRRs). RESULTS: A total of 240,257 new users of the ADHD medications were identified. The mean age was 45.0 ± 19.4 years and 55% of the cohort was female. Regular users of atomoxetine and amphetamines had a higher aIRR for developing ACG compared with non-users (aIRR = 2.55 95% CI [1.20-5.43] and 2.27 95% CI [1.42-3.63], respectively); while users of methylphenidate had a higher aIRR for developing OAG (aIRR = 1.23 95% CI [1.05-1.59]). CONCLUSIONS: Use of amphetamines and atomoxetine had a higher risk for ACG, while use of methylphenidate was associated with a higher risk for OAG. Given the prevalence of ADHD medication use (medically and recreationally), our current data on their associated risk of glaucoma have profound public health implications.

Norepinephrine Reuptake Inhibition, an Emergent Treatment for Neurogenic Orthostatic Hypotension.

The NET (norepinephrine transporter) is situated in the prejunctional plasma membrane of noradrenergic neurons. It is responsible for >90% of the norepinephrine uptake that is released in the autonomic neuroeffector junction. Inhibitors of this cell membrane transporter, known as norepinephrine reuptake inhibitors (NRIs), are commercially available for the treatment of depression and attention deficit hyperactivity disorder. These agents increase norepinephrine levels, potentiating its action in preganglionic and postganglionic adrenergic neurons, the latter through activation of α-1 adrenoreceptors. Previous studies found that patients with neurogenic orthostatic hypotension can improve standing blood pressure and reduce symptoms of neurogenic orthostatic hypotension after a single administration of the selective NRI atomoxetine. This effect was primarily observed in patients with impaired central autonomic pathways with otherwise normal postganglionic sympathetic fibers, known as multiple system atrophy. Likewise, patients with normal or high norepinephrine levels may benefit from NRIs. The long-term efficacy of NRIs for the treatment of neurogenic orthostatic hypotension-related symptoms is currently under investigation. In summary, an in-depth understanding of the pathophysiology of neurogenic orthostatic hypotension resulted in the discovery of a new therapeutic pathway targeted by NRI.