A Post-Hoc Analysis of Emotional Lability With Delayed-Release/Extended-Release Methylphenidate in Children Aged 6 to 12 Years of Age Participating in Two Phase 3 Clinical Trials.

OBJECTIVE: DR/ER-MPH (formerly HLD200) is an evening-dosed delayed-release and extended-release methylphenidate approved for the treatment of ADHD in patients ≥6 years. Post hoc analyses of two pivotal Phase 3 trials: HLD200-107 (NCT02493777) and HLD200-108 (NCT02520388) evaluated emotional lability (EL) with DR/ER-MPH treatment. METHODS: Differences in Conners Global Index-Parent (CGI-P) EL subscale scores and age- and gender-adjusted T-scores over an open-label titration phase (HLD200-107) and between treatment and placebo groups at endpoint (HLD200-108) were evaluated. RESULTS: In HLD200-107 (N = 117) mean CGI-P EL subscale scores improved from 5.3 to 1.3 (p < .0001) after 6 weeks; in HLD200-108 significant improvements were observed in the treatment group (n = 81) versus placebo (n = 80; 3.11 vs. 4.08; p = .0053). T-scores showed an improvement with DR/ER-MPH treatment in both trials. Few emotional adverse events (AEs) were reported. CONCLUSION: DR/ER-MPH treatment resulted in statistically significant improvements in EL to the level of non-ADHD peers as contextualized by T-scores.

Adverse Events During Dosing of Delayed-release/Extended-release Methylphenidate: Learnings From the Open-label Phase of a Registration Trial and a Real-world Postmarketing Surveillance Program.

PURPOSE: Delayed-release/extended-release methylphenidate (DR/ER-MPH) (formerly HLD200) is an evening-dosed agent used for the treatment of attention-deficit/hyperactivity disorder. Postmarketing surveillance data from approximately 74,000 patients exposed to DR/ER-MPH (up to June 17, 2022) were reported and compared with the open-label, treatment-optimization phase of a Phase III clinical trial to derive possible learnings on how to approach adverse events (AEs) that emerge during dose titration. METHODS: An analysis of AEs spontaneously reported to Ironshore in postmarketing surveillance included, where available, age, dose, timing, and discontinuations. Data were summarized using descriptive statistics. FINDINGS: A total of 395 children, adolescents, and adults reported 601 AEs in postmarketing surveillance. Five AEs were classified as serious. AEs preceded drug use discontinuation in 172 patients. Many AEs occurred early (52% were reported within 30 days) and at lower doses (54% were reported at 20 to 40 mg), similar to the trial data. Reported AEs included those similar in type but orders of magnitude lower in number than those from the clinical trial. IMPLICATIONS: No new safety concerns were revealed in this real-world setting compared with the safety profile identified in DR/ER-MPH trial data. In real-world practices, clinicians tended to discontinue DR/ER-MPH treatment after AE onset, whereas trial investigators continued to optimize treatment and found that AEs were generally tolerable, suggesting that health care practitioners may consider developing strategies to manage tolerability issues with DR/ER-MPH treatment on AE emergence rather than immediately discontinuing use of the drug to provide optimal therapeutic benefit. CLINICALTRIALS: gov identifier: NCT02493777.

Quantitative Characterization of the Smoothness of Extended-release Methylphenidate Pharmacokinetic Profiles.

Objective: Extended-release methylphenidate (ER-MPH) formulations used to treat attention deficit hyperactivity disorder (ADHD) have complex pharmacokinetic (PK) profiles, resulting from differing ratios of immediate-release and extended-release components and/or their site of absorption. This study aimed to evaluate the smoothness of PK curves of ER-MPHs. Design: The integral of the second derivative squared was evaluated for modeled PK curves, with smaller values indicating a smoother curve. The calculated smoothness of each PK curve was normalized by dividing by Cmax 2 to derive a normalized smoothness parameter appropriate across the dose range of each formulation. Calculations used modeled PK curves from 100mg delayed-release and ER-MPH (DR/ER-MPH), 54mg osmotic release oral system MPH (OROS MPH), 60mg MPH controlled-release delivery (MPH CD), 60mg ER-MPH oral suspension (MEROS), 20mg ER dexmethylphenidate (d-MPH ER), and 60mg multilayer-release MPH (MLR-MPH). Results: The Cmax2-normalized smoothness value was consistent across DR/ER-MPH doses, allowing for relevant comparisons across formulations. Normalized smoothness values differed widely; the lowest normalized smoothness was 0.05 with DR/ER-MPH and ranged up to 9.56 with d-MPH ER. Conclusion: DR/ER-MPH demonstrated a smoother PK profile compared to the highest dose of other ER-MPH formulations. While the benefits of a smooth PK profile remain to be tested clinically, having fewer peaks and troughs has been hypothesized to reduce waxing and waning of therapeutic effects throughout the day, and more gradual changes in MPH plasma levels have been hypothesized to lower the risk of likeability and potentially abate afternoon symptom rebound.

Symptomatic and Functional Response and Remission From the Open-Label Treatment-Optimization Phase of a Study With DR/ER-MPH in Children With ADHD.

Objective: Delayed-release and extended-release methylphenidate (DR/ER-MPH), the first stimulant predicted to be absorbed primarily in the colon, demonstrated significant improvements in attention-deficit/hyperactivity disorder (ADHD) symptoms and functional impairment from awakening until evening versus placebo in clinical trials. The clinical significance of these improvements was explored post hoc by examining response and remission thresholds as well as safety in the context of dose optimization.Methods: Data from the open-label, treatment-optimization phase of a phase 3 study of DR/ER-MPH in children (aged 6-12 years) with ADHD, as diagnosed by DSM-5 criteria and enrolled between July 2015 and March 2016, were analyzed. Thresholds for response (anchored to Clinical Global Impressions-Improvement scale [CGI-I] score of 1 or 2) and remission were applied to ADHD Rating Scale-IV (ADHD-RS-IV), Before School Functioning Questionnaire (BSFQ), and Parent Rating of Evening and Morning Behavior, Revised, Morning Subscale (PREMB-R AM) and Evening Subscale (PREMB-R PM) scores. Rates of response, remission, and treatment-emergent adverse events by starting dose were examined.Results: Mean DR/ER-MPH dose increased from 29.7 mg/d at baseline (51% on 20 mg/d; 49% on 40 mg/d) to 66.2 mg/d at week 6. At week 6, most participants achieved response/remission thresholds (response/remission: ADHD-RS-IV: 97%/89%; BSFQ: 98%/94%; PREMB-R AM: 94%/98%; PREMB-R PM: 91%/84%). More participants starting on a 40-mg versus 20-mg dose achieved thresholds at week 1 (P < .02). Weekly treatment-emergent adverse event rates over the open-label period were similar between starting doses.Conclusions: When DR/ER-MPH dosing was optimized for ADHD symptom control throughout the day, the majority of participants achieved thresholds indicating all-day control of ADHD symptoms and functional impairment to the level of their non-ADHD peers.Trial Registration: Data used in this post hoc analysis came from the study with ClinicalTrials.gov identifier: NCT02493777.

A Post Hoc Comparison of Prior ADHD Medication Dose and Optimized Delayed-release and Extended-release Methylphenidate Dose in a Pivotal Phase III Trial.

PURPOSE: HLD200 is the first evening-dosed, delayed-release and extended-release methylphenidate (DR/ER-MPH) designed to delay initial release of MPH and provide treatment effects throughout the day and into the evening for individuals with attention-deficit/hyperactivity disorder (ADHD). Because DR/ER-MPH is uniquely absorbed in the colon, it cannot be substituted for other ADHD medications on a milligram-per-milligram basis. To provide clinicians with a target dose range for DR/ER-MPH when transitioning patients from a prior ADHD medication, dose conversion ratios (DCRs) between prior medication doses and optimized doses of DR/ER-MPH were determined post hoc from a pivotal Phase III study of children (aged 6-12 years) with ADHD. METHODS: DR/ER-MPH doses were optimized over a 6-week open-label period. DCRs were calculated between optimized doses of DR/ER-MPH at week 6 and prior stable doses of ADHD medication. FINDINGS: Mean DCRs ranged from 1.8 to 4.3 for optimized DR/ER-MPH dose versus previous stable dose for individuals taking an extended-release stimulant monotherapy. DCRs for those taking an immediate-release stimulant monotherapy ranged from 4.7 to 6.0. IMPLICATIONS: In a Phase III trial of children with ADHD, optimized doses of DR/ER-MPH were higher than doses of prior ADHD medications, but the adverse event profile was consistent with that of other MPHs. Higher DCRs compared with those predicted by bioavailability differences are consistent with a predicted dose-dependent duration of effect for DR/ER-MPH: with increasing doses, absorption is extended but with an attenuated increase in Cmax compared with MPH formulations absorbed in the upper bowel. These data may help guide clinicians to optimize DR/ER-MPH doses. ClinicalTrials.gov identifier: NCT02493777.

Sleep-Associated Adverse Events During Methylphenidate Treatment of Attention-Deficit/Hyperactivity Disorder: A Meta-Analysis.

OBJECTIVE: Sleep disturbances are a feature of attention-deficit/hyperactivity disorder (ADHD) and an adverse event (AE) of methylphenidate treatment. The authors sought to clarify methylphenidate-associated sleep problems and how studies are affected by confounding factors. DATA SOURCES: Published studies in English collected via online databases and unpublished data from www.clinicaltrials.gov and US Food and Drug Administration websites. Sources were searched from inception to August 2017. STUDY SELECTION: Included were blinded placebo-controlled studies of youth with ADHD conducted in naturalistic settings, leading to 35 studies yielding 75 observations of sleep-related AEs. These studies comprised 3,079 drug-exposed and 2,606 placebo-treated patients. DATA EXTRACTION: Two PhD-level reviewers reviewed each study for inclusion. Four PhD/PharmD-level reviewers extracted data in duplicate. Discrepancies were resolved by discussion or, if needed, by the senior author. RESULTS: Increased pooled relative risks (RRs) were found for methylphenidate-associated sleep-related AEs for insomnia (general), initial insomnia, middle insomnia, combined insomnia, and sleep disorder. Several sample or study design features were significantly associated with the RR for sleep-related AEs and the methylphenidate formulation studied (P < .05). After correction for confounding variables, significant differences among drugs were found for initial insomnia, insomnia (general), and sleep disorder (P < .0001) as the other categories could not be tested due to insufficient studies. The findings also show that the RR and its interpretation are constrained by the placebo AE rate. CONCLUSIONS: Several types of insomnia and sleep problems are associated with methylphenidate treatment. Study design and sample features influence the RR statistic. By showing that the rate of placebo AEs impacts the RR, this study provides the field with a useful covariate for adjusting RR statistics.

Pharmacokinetics of HLD200, a Delayed-Release and Extended-Release Methylphenidate: Evaluation of Dose Proportionality, Food Effect, Multiple-Dose Modeling, and Comparative Bioavailability with Immediate-Release Methylphenidate in Healthy Adults.

OBJECTIVES: HLD200, an oral, once-daily, evening-dosed, delayed-release, and extended-release methylphenidate (DR/ER-MPH), was designed to provide efficacy from the early morning, throughout the day, and into the evening to individuals with attention-deficit/hyperactivity disorder. The objectives were to evaluate DR/ER-MPH pharmacokinetic (PK) properties in healthy adults, including dose proportionality, food effect, the potential of accumulation using multiple-dose modeling, and bioavailability compared to an immediate-release MPH (IR MPH). METHODS: Three open-label, single-dose, crossover studies were conducted, all with a 7-day washout between treatments. In Study I, 20 subjects received evening-dosed DR/ER-MPH (20 and 100 mg) followed by a medium-fat breakfast; 13 subjects received a subsequent 100-mg dose of DR/ER-MPH followed by a low-fat breakfast. In Study II, 18 subjects were evaluated after receiving evening-dosed DR/ER-MPH (100 mg) under 3 conditions: immediately after a high-fat meal, sprinkled on applesauce, and in a fasted state. In Study III, 11 and 12 subjects received evening-dosed DR/ER-MPH (100 mg) and morning-dosed IR MPH (20 mg), respectively. RESULTS: DR/ER-MPH demonstrated dose proportionality between 20- and 100-mg doses. DR/ER-MPH PK parameters were not significantly affected by breakfast content or by sprinkling capsule contents. A high-fat meal immediately preceding evening dosing did not affect total MPH exposure but lowered peak MPH exposure by 14% and 11% versus fasted and sprinkled states, and time to peak exposure was delayed by ∼2.5 hours; these PK differences are unlikely to be clinically significant. Based on multiple-dose simulations using data from Study I, negligible accumulation of DR/ER-MPH was predicted. The relative bioavailability for DR/ER-MPH compared to IR MPH was 73.9%. No serious adverse events (AEs) were reported, and the observed AEs were consistent with MPH. There were no discontinuations in Studies I and III, but three participants withdrew in Study II due to AEs. CONCLUSIONS: Evening-dosed DR/ER-MPH demonstrated dose proportionality and can be administered with or without food. Significant accumulation is unlikely with multiple dosing.

The NCA sodium leak channel is required for persistent motor circuit activity that sustains locomotion.

Persistent neural activity, a sustained circuit output that outlasts the stimuli, underlies short-term or working memory, as well as various mental representations. Molecular mechanisms that underlie persistent activity are not well understood. Combining in situ whole-cell patch clamping and quantitative locomotion analyses, we show here that the Caenorhabditis elegans neuromuscular system exhibits persistent rhythmic activity, and such an activity contributes to the sustainability of basal locomotion, and the maintenance of acceleration after stimulation. The NALCN family sodium leak channel regulates the resting membrane potential and excitability of invertebrate and vertebrate neurons. Our molecular genetics and electrophysiology analyses show that the C. elegans NALCN, NCA, activates a premotor interneuron network to potentiate persistent motor circuit activity and to sustain C. elegans locomotion. Collectively, these results reveal a mechanism for, and physiological function of, persistent neural activity using a simple animal model, providing potential mechanistic clues for working memory in other systems.

Internet blood glucose monitoring systems provide lasting glycemic benefit in type 1 and 2 diabetes: a systematic review.

Internet blood glucose monitoring systems (IBGMS) are associated with improved glycemic control in patients with type 2 diabetes (T2D) who are pharmacologically managed, using oral agents or insulin. IBGMS improves glycemic levels in patients with type 1 diabetes (T1D). IBGMS has not led to increased hypoglycemia. Mechanisms underlying IBGMS-associated glycemic improvement extend beyond optimizing insulin dose titration. The most important effects seem to be associated with increased patient self-motivation and improved patient-physician communication. IBGMS have been recommended in clinical practice guidelines, and their effectiveness and safety in trials suggest that this approach is appropriate for patients with T1D or T2D.

Mmp25ß facilitates elongation of sensory neurons during zebrafish development.

Matrix metalloproteinases (MMPs) are a large and complex family of zinc-dependent endoproteinases widely recognized for their roles in remodeling the extracellular matrix (ECM) during embryonic development, wound healing, and tissue homeostasis. Their misregulation is central to many pathologies, and they have therefore been the focus of biomedical research for decades. These proteases have also recently emerged as mediators of neural development and synaptic plasticity in vertebrates, however, understanding of the mechanistic basis of these roles and the molecular identities of the MMPs involved remains far from complete. We have identified a zebrafish orthologue of mmp25 (a.k.a. leukolysin; MT6-MMP), a membrane-type, furin-activated MMP associated with leukocytes and invasive carcinomas, but which we find is expressed by a subset of the sensory neurons during normal embryonic development. We detect high levels of Mmp25ß expression in the trigeminal, craniofacial, and posterior lateral line ganglia in the hindbrain, and in Rohon-Beard cells in the dorsal neural tube during the first 48 h of embryonic development. Knockdown of Mmp25ß expression with morpholino oligonucleotides results in larvae that are uncoordinated and insensitive to touch, and which exhibit defects in the development of sensory neural structures. Using in vivo zymography, we observe that Mmp25ß morphant embryos show reduced Type IV collagen degradation in regions of the head traversed by elongating axons emanating from the trigeminal ganglion, suggesting that Mmp25ß may play a pivotal role in mediating ECM remodeling in the vicinity of these elongating axons.

Hyperactivation of B-type motor neurons results in aberrant synchrony of the Caenorhabditis elegans motor circuit.

Excitatory acetylcholine motor neurons drive Caenorhabditis elegans locomotion. Coordinating the activation states of the backward-driving A and forward-driving B class motor neurons is critical for generating sinusoidal and directional locomotion. Here, we show by in vivo calcium imaging that expression of a hyperactive, somatodendritic ionotropic acetylcholine receptor ACR-2(gf) in A and B class motor neurons induces aberrant synchronous activity in both ventral- and dorsal-innervating B and A class motor neurons. Expression of ACR-2(gf) in either ventral- or dorsal-innervating B neurons is sufficient for triggering the aberrant synchrony that results in arrhythmic convulsions. Silencing of AVB, the premotor interneurons that innervate B motor neurons suppresses ACR-2(gf)-dependent convulsion; activating AVB by channelrhodopsin induces the onset of convulsion. These results support that the activity state of B motor neurons plays an instructive role for the coordination of motor circuit.

Proprioceptive coupling within motor neurons drives C. elegans forward locomotion.

Locomotion requires coordinated motor activity throughout an animal's body. In both vertebrates and invertebrates, chains of coupled central pattern generators (CPGs) are commonly evoked to explain local rhythmic behaviors. In C. elegans, we report that proprioception within the motor circuit is responsible for propagating and coordinating rhythmic undulatory waves from head to tail during forward movement. Proprioceptive coupling between adjacent body regions transduces rhythmic movement initiated near the head into bending waves driven along the body by a chain of reflexes. Using optogenetics and calcium imaging to manipulate and monitor motor circuit activity of moving C. elegans held in microfluidic devices, we found that the B-type cholinergic motor neurons transduce the proprioceptive signal. In C. elegans, a sensorimotor feedback loop operating within a specific type of motor neuron both drives and organizes body movement.

Releasing the inner inhibition for axon regeneration.

The adult mammalian central nervous system exhibits restricted regenerative potential. Chen et al. (2011) and El Bejjani and Hammarlund (2012) used Caenorhabditis elegans to uncover intrinsic factors that inhibit regeneration of axotomized mature neurons, opening avenues for potential therapeutics.

An imbalancing act: gap junctions reduce the backward motor circuit activity to bias C. elegans for forward locomotion.

A neural network can sustain and switch between different activity patterns to execute multiple behaviors. By monitoring the decision making for directional locomotion through motor circuit calcium imaging in behaving Caenorhabditis elegans (C. elegans), we reveal that C. elegans determines the directionality of movements by establishing an imbalanced output between the forward and backward motor circuits and that it alters directions by switching between these imbalanced states. We further demonstrate that premotor interneurons modulate endogenous motoneuron activity to establish the output imbalance. Specifically, the UNC-7 and UNC-9 innexin-dependent premotor interneuron-motoneuron coupling prevents a balanced output state that leads to movements without directionality. Moreover, they act as shunts to decrease the backward-circuit activity, establishing a persistent bias for the high forward-circuit output state that results in the inherent preference of C. elegans for forward locomotion. This study demonstrates that imbalanced motoneuron activity underlies directional movement and establishes gap junctions as critical modulators of the properties and outputs of neural circuits.

A co-operative regulation of neuronal excitability by UNC-7 innexin and NCA/NALCN leak channel.

Gap junctions mediate the electrical coupling and intercellular communication between neighboring cells. Some gap junction proteins, namely connexins and pannexins in vertebrates, and innexins in invertebrates, may also function as hemichannels. A conserved NCA/Dmα1U/NALCN family cation leak channel regulates the excitability and activity of vertebrate and invertebrate neurons. In the present study, we describe a genetic and functional interaction between the innexin UNC-7 and the cation leak channel NCA in Caenorhabditis elegans neurons. While the loss of the neuronal NCA channel function leads to a reduced evoked postsynaptic current at neuromuscular junctions, a simultaneous loss of the UNC-7 function restores the evoked response. The expression of UNC-7 in neurons reverts the effect of the unc-7 mutation; moreover, the expression of UNC-7 mutant proteins that are predicted to be unable to form gap junctions also reverts this effect, suggesting that UNC-7 innexin regulates neuronal activity, in part, through gap junction-independent functions. We propose that, in addition to gap junction-mediated functions, UNC-7 innexin may also form hemichannels to regulate C. elegans' neuronal activity cooperatively with the NCA family leak channels.

PHRs: bridging axon guidance, outgrowth and synapse development.

Axon guidance, outgrowth, and synapse formation are interrelated developmental events during the maturation of the nervous system. Establishing proper synaptic connectivity requires precise axon navigation and a coordinated switch between axon outgrowth and synaptogenesis. The PHR (human Pam, mouse Phr1, zebrafish Esrom, DrosophilaHighwire, and C. elegansRPM-1) protein family regulates both axon and synapse development through their biochemical and functional interactions with multiple signaling pathways. Recent studies have begun to elucidate a common underlying mechanism for PHR functions: Consisting of motifs that affect intracellular signaling, selective protein degradation, and cytoskeleton organization, PHR proteins probably mediate the transition between axon outgrowth and synaptogenesis through integrating intracellular signaling and microtubule remodeling.

Neuronal polarity is regulated by a direct interaction between a scaffolding protein, Neurabin, and a presynaptic SAD-1 kinase in Caenorhabditis elegans.

The establishment of axon-dendrite identity in developing neurites is essential for the development of a functional nervous system. The SAD serine-threonine kinases have been implicated in regulating neuronal polarization and synapse formation. Here, we show that the C. elegans SAD-1 kinase regulates axonal identity and synapse formation through distinct mechanisms. We identified a scaffolding protein, Neurabin (NAB-1), as a physiological binding partner of SAD-1. Both sad-1 and nab-1 loss-of-function mutants display polarity defects in which synaptic vesicles accumulate in both axons and dendrites. We show that sad-1 and nab-1 function in the same genetic pathway to restrict axonal fate. Unlike sad-1, nab-1 mutants display normal morphology of vesicle clusters. Strikingly, although the physical interaction of NAB-1 with SAD-1 is necessary for polarity, it is dispensable for synapse morphology. We propose that Neurabin functions as a scaffold to facilitate SAD-1-mediated phosphorylation for substrates specific for restricting axonal fate during neuronal polarization.