Product labeling accuracy and contamination analysis of commercially available cannabidiol product samples.

Background and objective: Commercially available cannabidiol (CBD) products are increasingly being used for medicinal purposes, including for the treatment of various neurological conditions, but there are growing concerns around adherence to quality control measures that protect consumers. This study was conducted to assess the purity and label accuracy of commercially available CBD products. Methods: Commercially available CBD products were chosen from the open stream of commerce in the United States based on formulations as a tincture, gummy, vape, or topical product. Cannabinoid concentrations were analyzed to verify label accuracy including "full spectrum," "broad spectrum," and "CBD isolate" claims on the product label. Analysis for the presence of contaminants included evaluation for heavy metals, pesticides, and residual solvents. Labeled and actual total amounts of CBD and levels of impurities such as heavy metals, residual solvents, and pesticides were measured. Results: A total of 202 CBD products (100 tinctures, 48 gummies, 34 vape products, and 20 topicals) were chosen to represent a broad sample in the United States. Of the products tested (full spectrum, n = 84; broad spectrum, n = 28; CBD isolate, n = 37), 26% did not meet the definition for product type claimed on the packaging. The majority of products (74%) deviated from their label claim of CBD potency by at least 10%. Heavy metals were detected 52 times across 44 of the 202 products tested, with lead being the most prevalent heavy metal. Residual solvents were detected 446 times across 181 of 202 products, with the highest concentrations reported for hexane, m/p-xylene, methanol, and o-xylene. Of 232 pesticides tested, 26 were found 55 times across 30 products. A total of 3% of heavy metals, 1% of residual solvents, and 1% of pesticides violated >1 regulatory threshold. Discussion: This study demonstrated that the majority of commercially available CBD products tested within the current study are inaccurately labeled. Heavy metals, residual solvents, and pesticides were found in several products, some of which violated regulatory thresholds. Thus, uniform compliance with CBD quality control measures is lacking and raises consumer protection concerns. Improved regulatory oversight of this industry is recommended.

Lacosamide extended-release capsules are bioequivalent to lacosamide immediate-release tablets: Pharmacokinetic observations and simulations.

OBJECTIVES: Assess the bioequivalence of lacosamide extended-release (XR) capsules and immediate-release (IR) tablets and answer real-world clinical questions regarding the use of lacosamide XR. METHODS: An open-label, randomized, two-treatment, two-sequence, oral comparative bioavailability study was conducted to assess the bioequivalence of two lacosamide formulations. Participants were randomized 1:1 to receive lacosamide XR capsules (400 mg once-daily) or IR tablets (200 mg twice-daily) in 1 of 2 sequences over 7-day periods. Primary outcome was the area under the lacosamide concentration-time curve over 24 h at steady-state (AUC0-τ,ss). Secondary outcomes were maximum (Cmax,ss) and minimum concentrations at steady-state (Cmin,ss). Bioequivalence was established when 90% confidence intervals (CIs) for geometric least square means ratios (GLSMs) were between 80% and 125%. Adverse events (AEs) and other safety outcomes were also assessed. Pharmacokinetic simulations, including adherent and partially adherent dosing scenarios with XR and IR formulations, modeled the clinical use of lacosamide XR. RESULTS: Thirty-five healthy adult males were enrolled in the bioequivalence study. After 7 days of study drug, mean AUC0-τ,ss, Cmax,ss, and Cmin,ss values were similar between XR and IR formulations; all 90% CIs for GLSMs were between 80% and 125%. AEs were mild and no serious AEs or other clinically significant safety findings were observed. Pharmacokinetic simulations suggested that partial adherence affected formulations similarly; and the best strategy for switching formulations was to take the morning lacosamide IR dose followed by the evening lacosamide XR dose, as this resulted in the most consistent lacosamide plasma concentrations. CONCLUSIONS: Once-daily lacosamide XR capsules were bioequivalent to twice-daily lacosamide IR tablets. Pharmacokinetic simulations indicated lacosamide XR and IR formulations were similarly affected by partial adherence, though once-daily dosing with lacosamide XR may offer clinical advantages, and formulations can be easily switched. These results support the use of lacosamide XR capsules as a once-daily alternative to lacosamide IR tablets.

Zonisamide: A Comprehensive, Updated Review for the Clinician.

Purpose of Review: Zonisamide (ZNS) was first approved in the United States in 2000 for the adjunctive treatment of patients aged 16 years or older with partial (focal) seizures. Although ZNS has been proven to treat multiple seizure types, it has been largely underutilized in US clinical practice. Recent Findings: Published literature demonstrated that antiseizure medications (ASMs) acting on Na+ and Ca2+ channels may add beneficial effects in many seizure types by reducing seizure frequency and leading to overall improvements. In addition, effects of ZNS may lead to clinical improvements in Parkinson disease, alcohol and sleep disorders, pain, and migraine. ZNS is available in multiple formulations and is a safe and effective, broad spectrum ASM. Summary: The purpose of this review was to provide an update to what is known about the efficacy of ZNS and where it shows benefits in the treatment of patients with epilepsy and other CNS disorders through its many unique mechanisms of action.

Practical Questions About Rescue Medications for Acute Treatment of Seizure Clusters in Children and Adolescents with Epilepsy in the USA: Expanding Treatment Options to Address Unmet Needs.

Epilepsy is a common pediatric neurological condition, affecting approximately 470,000 children in the USA and having a prevalence of 0.9% in the global population of approximately 2.6 billion children. Epilepsy is associated with disruptions in several areas of a child's life, including medical burden, quality of life, cognitive outcomes, and higher risk of mortality. Additionally, some pediatric patients may experience acute seizure emergencies such as seizure clusters (also called acute repetitive seizures), which are intermittent increases in seizure activity that differ from the patient's usual seizure pattern and may occur despite daily antiseizure drug administration. Seizure clusters increase a patient's risk for status epilepticus and emergency room visits. Benzodiazepines are the main category of drugs used as acute seizure therapies for seizure clusters. This narrative review provides a practical discussion of care for pediatric patients with epilepsy and seizure clusters exploring such topics as details about the US Food and Drug Administration-approved acute seizure therapies, safety and ease of use of these medications, benefits of seizure action plans to help ensure optimal treatment, and considerations for transitioning a pediatric patient with acute seizure therapy to adult healthcare management.

Lamotrigine use and potential for adverse cardiac effects: A retrospective evaluation in a Veteran population.

OBJECTIVE: To identify the impact of lamotrigine (LTG) on cardiac rhythm and conduction abnormalities for Veterans, an especially vulnerable population. BACKGROUND: In October 2020 the US Food and Drug Administration (FDA) added a new warning to the label of lamotrigine (Lamictal™) regarding its potential to cause cardiac rhythm and conduction abnormalities [1]. This warning came following in vitro data which suggested Class IB antiarrhythmic effects occurring at clinically achievable concentrations of lamotrigine [2]. However, it is unclear whether the in vitro findings will result in adverse clinical outcomes. Our objective was to assess for evidence for adverse clinical outcomes in a vulnerable population and examine for subtler signs of an association between lamotrigine and cardiac rhythm disturbances. METHODS: A retrospective chart review was conducted using records between 10-01-2017 and 07-06-2021, identifying patients at the William S. Middleton Memorial Veterans Hospital who were prescribed lamotrigine. Data collected included: dates of lamotrigine initiation or discontinuation, lamotrigine dosing over the time of the prescription and maximum lamotrigine dose, any cardiac-related ICD-10-CM codes or a history of a cardiology appointment, EKGs with any abnormalities or changes, any concomitantly prescribed medications with known potential to cause cardiac abnormalities, any cardiac deaths. This retrospective chart review was approved by the University of Wisconsin-Madison Institutional Review Board. RESULTS: Two hundred and thirty-three (189 male) patients with a lamotrigine prescription and 41.2 % (n = 96) of these patients had an EKG performed while prescribed lamotrigine. The average age of patients was 64.3 ± 13.0 (range 29 to 90) years and mean maximum lamotrigine daily dose was 250.8 ± 148.2 mg (range 25 to 800 mg). Nearly half (47.9 %, 46/96) of the patients were prescribed a concomitant sodium channel blocking medication in addition to lamotrigine. Eighty-four of the patients (87.5 %, 84/96) had a cardiac diagnosis, while 12 (12.5 %, 12/96) did not. A total of 12 deaths occurred within the review period, with two cardiac deaths from congestive heart failure. Four cases did not have information on cause of death. No LTG-associated cardiac adverse effects were noted as part of clinical care, though rash was noted in 5 cases. A total of 7 (7.3 %, 7/96) patients were found to have EKG abnormalities potentially related to lamotrigine, including 7.1 % (6/84) of those with a cardiac diagnosis and 8.3 % (1/12) of those without a cardiac diagnosis. CONCLUSIONS: While recent FDA warnings have suggested caution regarding cardiac complications associated with lamotrigine based on in vitro studies, the clinical implications are uncertain. Despite selecting a particularly vulnerable population, this retrospective chart review did not identify any deaths due to cardiac rhythm or conduction causes, nor demonstrate unambiguous cardiac complications related to lamotrigine. Even using permissive criteria (including any prolonged PR or QTc) to examine for subtle effects, only a low incidence (<10 %) of potential complications was found. Broader implications of this study are limited by the number of patients included and the retrospective nature of the study. Therefore, further studies are warranted to evaluate a link between cardiac complications and the use of lamotrigine, including the role of concomitant medications such as other sodium channel blocking agents and psychotropic medications.

Patterns of antiseizure medication utilization in the Human Epilepsy Project.

OBJECTIVE: This study was undertaken to ascertain the natural history and patterns of antiseizure medication (ASM) use in newly diagnosed focal epilepsy patients who were initially started on monotherapy. METHODS: The data were derived from the Human Epilepsy Project. Differences between the durations of the most commonly first prescribed ASM monotherapies were assessed using a Cox proportional hazards model. Subjects were classified into three groups: monotherapy, sequential monotherapy, and polytherapy. RESULTS: A total of 443 patients were included in the analysis, with a median age of 32 years (interquartile range [IQR] = 20-44) and median follow-up time of 3.2 years (IQR = 2.4-4.2); 161 (36.3%) patients remained on monotherapy with their initially prescribed ASM at the time of their last follow-up. The mean (SEM) and median (IQR) duration that patients stayed on monotherapy with their initial ASM was 2.1 (2.0-2.2) and 1.9 (.3-3.5) years, respectively. The most commonly prescribed initial ASM was levetiracetam (254, 57.3%), followed by lamotrigine (77, 17.4%), oxcarbazepine (38, 8.6%), and carbamazepine (24, 5.4%). Among those who did not remain on the initial monotherapy, 167 (59.2%) transitioned to another ASM as monotherapy (sequential monotherapy) and 115 (40.8%) ended up on polytherapy. Patients remained significantly longer on lamotrigine (mean = 2.8 years, median = 3.1 years) compared to levetiracetam (mean = 2.0 years, median = 1.5 years) as a first prescribed medication (hazard ratio = 1.5, 95% confidence interval = 1.0-2.2). As the study progressed, the proportion of patients on lamotrigine, carbamazepine, and oxcarbazepine as well as other sodium channel agents increased from a little more than one third (154, 34.8%) of patients to more than two thirds (303, 68.4%) of patients. SIGNIFICANCE: Slightly more than one third of focal epilepsy patients remain on monotherapy with their first prescribed ASM. Approximately three in five patients transition to monotherapy with another ASM, whereas approximately two in five end up on polytherapy. Patients remain on lamotrigine for a longer duration compared to levetiracetam when it is prescribed as the initial monotherapy.

Patterns of psychotropic drug use in veterans with epilepsy: Do drug interactions matter?

RATIONALE: Patients with epilepsy are likely to suffer from psychiatric comorbidities, including depression and anxiety. They often require treatment with multiple psychotropic drugs (PDs). While it is clear that CYP-inducing ASMs (EIASMs) can increase the oral clearance of multiple medications (thus lowering systemic exposure), it is less clear that all PK interactions are clinically meaningful (e.g. lower efficacy). As a first step in addressing this issue, this study sought to quantify the potential impact of ASM choice, whether EIASM or non-inducer (NIASM), on surrogate markers of suggestive of clinical use, including resultant antidepressant (AD) or antipsychotic (AP) dose, frequency of combination use of AD & AP, and number of multiple drug switches of PDs. Our hypothesis is that because of PK interactions, EIAED treatment would be associated with higher psychotropic drug doses, more frequent Rx adjustments and poly psychotropic comedication, all in order to optimize therapeutic response. METHODS: Using VA pharmacy and national encounter databases, veterans with epilepsy were identified based on having a seizure diagnosis and being prescribed concomitantly an ASM and a psychotropic drug for at least 365 days between 10/1/2010 and 9/30/2014. Patients for whom psychotropic drugs were prescribed any time between beginning and end prescriptions dates of ASMs were considered. Among those, patients receiving both an EIASM + NEIASM concomitantly were categorized with the EIASM group. Patients were evaluated for AD only, AP only and both (AD & AP). To compute average drug doses per day, averages for each patient were computed and averaged again. Multiple drug switches were defined to be for patients who had been prescribed more than three psychotropic drugs during the observation period. Pearson's Chi-Square test was used to compare relative proportions of AD, AP and AD + AP in both groups. RESULTS: In all, 16,188 patients were identified (57.0% on EIASM, 43.0% on NIASM) with a mean age of 58.7 years (91.2% male). A larger proportion of patients on EIASM received mono treatment with any psychotropic drug, as compared to NIASM (42.0% vs 36.1%). Among all, 59.6% received AD only, 6.5% received AP only, and 33.8% received both concurrently. Of EIASM, 62.5% were on AD, 5.9% on AP, and 31.7% on both AP & AD. For NIASM, 55.9% received AD, 7.4% AP, and 36.7% on AD & AP.Chi-square showed that the distribution of PD was statistically different between EIASM and NIASM groups. Z tests showed that each difference (AD, AP and both) in proportions was statistically significant (p values (4 tests, one Chi-square, 3 Z tests <0.001) between EIASM vs NIASM. Interestingly, mean doses of AD or AP did not appear to differ between ASM groups. CONCLUSIONS: Concurrent psychotropic drug use is quite common in the VA population with epilepsy, and a large number of patients still receive enzyme-inducing ASMs that may complicate other medical therapies. Interestingly, in seeming contradiction to our hypothesis, mean daily doses of either AD or AP did not appear to differ between inducers vs non-inducers. Similarly, use of polytherapy, and/or multiple trials of various psychotropic drugs did not appear increased in the CYP-induced group. In fact, combination therapy of AD + AP was higher in NIASM than EIASM. These data suggest that perhaps these types of PK interactions may not in fact result in meaningful clinical differences. Since the present analyses did not include clinical psychiatric measures, future analyses examining direct clinical outcomes are clearly warranted.

Real-world, long-term evaluation of the tolerability and therapy retention of Epidiolex® (cannabidiol) in patients with refractory epilepsy.

OBJECTIVE: Epidiolex® (CBD) is FDA-approved for seizures associated with Lennox-Gastaut syndrome (LGS), Dravet syndrome (DS), and tuberous sclerosis complex (TSC). Phase III studies suggest that certain adverse effects (AEs), possibly linked to pharmacokinetic/pharmacodynamic (PK/PD) interactions may be therapy-limiting. We sought to identify these factors that contribute to treatment success and retention of therapy. METHODS: A single-center, retrospective review of patients with refractory epilepsy taking Epidiolex® was performed. Kaplan-Meier analysis was performed to describe Epidiolex® retention, as a measure of overall effectiveness. RESULTS: One hundred and twelve patients were screened; 4 were excluded due to loss to follow-up or never starting Epidiolex®. Of 108 patients, mean age was 20.3 years (13.1, range 2 to 63), and 52.8% were female. Mean initial and maintenance doses were 5.3 mg/kg/day (1.3) and 15.3 mg/kg/day (5.8), respectively. At the final evaluation, 75% of patients remained on Epidiolex®. The 25th percentile for discontinuation was 19 months. 46.3% of patients experienced at least one treatment-emergent adverse effect (TEAE) with 14.5% d/c Epidiolex® due to treatment emerging adverse effects (TEAE). The most common reasons for discontinuation were lack of efficacy (37%), increased seizure activity (22%), worsened behavior (22%), and sedation (22%). One out of 27 discontinuations was due to liver function test (LFT) elevations (3.7%). At initiation, 47.2% were concurrently taking clobazam, and 39.2% of those patients had an initial clobazam dose decrease. 53% of patients were able to either discontinue or lower the dose of at least one other antiseizure medication. SIGNIFICANCE: Epidiolex® is generally well-tolerated and the majority continued long-term treatment. Patterns of adverse effects were similar to clinical trials, however gastrointestinal complaints, and significant LFT elevations were less common. Our data suggest most patients discontinue within the first several months of treatment and suggest that further studies designed to evaluate early identification and potential mitigation of adverse effects and including drug interactions are warranted.

Mood and Anxiety Disorders and Suicidality in Patients With Newly Diagnosed Focal Epilepsy: An Analysis of a Complex Comorbidity.

BACKGROUND AND OBJECTIVES: Mood, anxiety disorders, and suicidality are more frequent in people with epilepsy than in the general population. Yet, their prevalence and the types of mood and anxiety disorders associated with suicidality at the time of the epilepsy diagnosis are not established. We sought to answer these questions in patients with newly diagnosed focal epilepsy and to assess their association with suicidal ideation and attempts. METHODS: The data were derived from the Human Epilepsy Project study. A total of 347 consecutive adults aged 18-60 years with newly diagnosed focal epilepsy were enrolled within 4 months of starting treatment. The types of mood and anxiety disorders were identified with the Mini International Neuropsychiatric Interview, whereas suicidal ideation (lifetime, current, active, and passive) and suicidal attempts (lifetime and current) were established with the Columbia Suicidality Severity Rating Scale (CSSRS). Statistical analyses included the t test, χ2 statistics, and logistic regression analyses. RESULTS: A total of 151 (43.5%) patients had a psychiatric diagnosis; 134 (38.6%) met the criteria for a mood and/or anxiety disorder, and 75 (21.6%) reported suicidal ideation with or without attempts. Mood (23.6%) and anxiety (27.4%) disorders had comparable prevalence rates, whereas both disorders occurred together in 43 patients (12.4%). Major depressive disorders (MDDs) had a slightly higher prevalence than bipolar disorders (BPDs) (9.5% vs 6.9%, respectively). Explanatory variables of suicidality included MDD, BPD, panic disorders, and agoraphobia, with BPD and panic disorders being the strongest variables, particularly for active suicidal ideation and suicidal attempts. DISCUSSION: In patients with newly diagnosed focal epilepsy, the prevalence of mood, anxiety disorders, and suicidality is higher than in the general population and comparable to those of patients with established epilepsy. Their recognition at the time of the initial epilepsy evaluation is of the essence.

PaxlovidTM Information From FDA and Guidance for AES Members.

This American Epilepsy Society (AES) official statement provides information and preliminary guidance to Society members related to the U.S. Food & Drug Administration (FDA) December 22, 2021 Emergency Use Authorization for Paxlovid™ for the oral treatment of mild to moderate COVID-19 in adults and children (≥12 years and weighing ≥40 kg). Paxlovid is likely to be widely prescribed, and important considerations for patients on antiseizure medications (ASMs) include key contraindications and potential toxicity or dose adjustments while taking Paxlovid. This statement highlights concerns and provides information about their pharmacologic basis. Of particular concern, concomitant use of Paxlovid with the ASMs carbamazepine, phenobarbital, phenytoin, and primidone is contraindicated, because they are strong inducers of the CYP3A4 isozyme that metabolizes Paxlovid and thereby could cause loss of virologic response and development of resistance. Alternate oral or intravenous COVID-19 treatments should be considered. A second concern is that Paxlovid may increase the plasma concentrations of many ASMs, because it inhibits the CYP3A4 isozyme. ASMs that are metabolized, at least in part, by CYP3A4 include cannabidiol, carbamazepine, clobazam, clonazepam, diazepam, ethosuximide, everolimus, felbamate, lacosamide, midazolam, oxcarbazepine, perampanel, stiripentol, tiagabine, and zonisamide. Patients receiving these medications may warrant closer monitoring while being treated with Paxlovid.

Rescue Treatments for Seizure Clusters.

Treatment of seizure clusters endeavors to prevent additional seizures and avoid progression to conditions such as prolonged seizures and status epilepticus. Rescue therapies are key components of seizure action plans (SAPs) for individuals with seizure clusters. Three rescue therapies are approved in the United States for the treatment of seizure clusters: diazepam rectal gel, midazolam nasal spray, and diazepam nasal spray. Diazepam rectal gel is an effective rescue therapy for seizure clusters, though adults and adolescents may have social reservations regarding its administration. Intranasal delivery of midazolam or diazepam is a promising alternative to rectal administration because these formulations offer easy, socially acceptable administration exhibit a rapid onset, and allow for the possibility of self-administration. Off-label benzodiazepines, such as orally disintegrating lorazepam and intranasal use of an intravenous (IV) formulation of midazolam via nasal atomizer, are less well characterized regarding bioavailability and tolerability compared with approved agents.

Opportunities for Community Pharmacists to Counsel Patients With Epilepsy and Seizure Clusters to Overcome Barriers and Foster Appropriate Treatment.

Some patients with epilepsy experience seizure clusters, which may be defined as 2 or more seizures occurring within 24 hours. Left untreated, seizure clusters increase the risk for physical injury and may progress to status epilepticus, irreversible neurologic injury, and death. Rescue therapy is based on benzodiazepine treatment. Prompt, appropriate use should be specified in patients' individualized seizure action plans. Most seizure clusters occur outside the hospital setting. The ideal rescue therapy allows for easy and quick administration by a nonmedical person, which may minimize the need for intervention by emergency medical personnel or transportation to the hospital. In the 2 decades before the approval of 2 intranasal benzodiazepines in 2019 and 2020, rectal diazepam was the only route of administration approved by the US Food and Drug Administration specifically for seizure clusters. Each of the approved intranasal formulations has a unique profile. Both offer a convenient and socially acceptable route of administration. Recognition of seizure clusters and timing of proper administration are key to successful use of rescue therapy. Pharmacists' counseling plays an important role in reinforcing when and how to appropriately administer rescue therapies and the importance of consistently using rescue treatment when indicated to promote effective management. This review includes resources for pharmacists, patients, and caregivers; reviews currently available treatments; and discusses seizure action plans that support effective treatment of seizure clusters.

Rescue therapies for seizure clusters: Pharmacology and target of treatments.

The primary goal of treatment for seizure clusters is cessation of the cluster to avoid progression to more severe conditions, such as prolonged seizures and status epilepticus. Rescue therapies are key components of treatment plans for patients with seizure clusters. Three rescue therapies are approved in the United States for the treatment of seizure clusters: diazepam rectal gel, midazolam nasal spray, and diazepam nasal spray. This review characterizes the pharmacological function of rescue therapies for seizure clusters, as well as describing γ-aminobutyric acid A (GABAA ) receptor functions. GABAA receptors are heteropentamers, consisting primarily of α1-6, ß1-3, γ2, and δ subunits in the central nervous system. These subunits can traffic to and from the membrane to regulate membrane potential. Benzodiazepines, such as diazepam and midazolam, are positive allosteric modulators of GABAA receptors, the activation of which leads to an increase in intracellular chloride, hyperpolarization of the cell membrane, and a reduction in excitation. GABAA receptor subunit mutations, dysregulation of trafficking, and degradation are associated with epilepsy. Although benzodiazepines are effective GABAA receptor modulators, individual formulations have unique profiles in practice. Diazepam rectal gel is an effective rescue therapy for seizure clusters; however, adults and adolescents may have social reservations regarding its administration. Intranasal delivery of midazolam or diazepam is a promising alternative to rectal administration because these formulations offer easy, socially acceptable administration and exhibit a rapid onset. Off-label benzodiazepines, such as orally disintegrating lorazepam and intranasal use of an intravenous formulation of midazolam via nasal atomizer, are less well characterized regarding bioavailability and tolerability compared with approved agents.

Considerations for determining the efficacy of new antiseizure medications in children age 1 month to younger than 2 years.

OBJECTIVES: Drug treatment for children with epilepsy should, ideally, be governed by evidence from adequate and well-controlled clinical studies. However, these studies are difficult to conduct, and so direct evidence supporting the informed use of specific drugs is often lacking. The Research Roundtable for Epilepsy (RRE) met in 2020 to align on an approach to therapy development for focal seizures in children age 1 month <2 years of age. METHODS: The RRE reviewed the regulatory landscape, epidemiology, seizure semiology, antiseizure medicine pharmacology, and safety issues applicable to this population. RESULTS: After reviewing evidence, the conclusion was that pediatric efficacy trials would be impracticable to conduct but a waiver of the regulatory requirement to conduct any study would lead to an absence of information to guide dosing in a critical population. Review of available data and discussion of RRE attendees led to the conclusion that the requirements for extrapolation of efficacy from older children down to infants from age 1 month to <2 years old appeared to be met. After the RRE, the US Food and Drug Administration (FDA) approved brivaracetam for use in children with focal epilepsy above the age of 1 month in August 2021 and lacosamide in October 2021, both based on the principle of extrapolation from data in older children. SIGNIFICANCE: These recommendations should result in more rapid accessibility of antiseizure medications for infants.

Impact of Clinical Pharmacists on Access to Care in an Epilepsy Clinic.

Background: Epilepsy affects about 1% of the world population and is one of the most burdensome diseases in terms of disability-adjusted life-years. The demand for neurologists and epileptologists is expected to exceed current supply by 2025. One potential strategy to increase access to epilepsy care is to utilize clinical pharmacist practitioners (CPPs) with a broad scope of practice. Methods: Appointments at the William S. Middleton Memorial Veterans Hospital (WSMVH) epilepsy clinic in Madison, Wisconsin, were reviewed to determine the percentage of appointments completed by a CPP or clinical pharmacy resident from October 2019 to May 2021. Additionally, a retrospective chart review was completed on 446 veterans to identify the types of interventions made by a CPP or clinical pharmacy resident at each appointment from October 2017 to June 2021. Results: The CPP or clinical pharmacy resident held approximately 43% of 591 total appointments and spent a mean 27 minutes with each patient. Medication interventions occurred at 27% of 446 appointments in the retrospective chart review. Half (50.4%) of all patients seen by a CPP completed at least 1 mental health screening. Conclusion: The integration of a CPP WSMVH epilepsy clinic allowed for greater and more timely access to care and allowed for the epileptologists to focus their time on new consults, Epilepsy Monitoring Unit admissions, and higher acuity cases.

Analysis of cannabidiol (CBD) and THC in nonprescription consumer products: Implications for patients and practitioners.

PURPOSE: Cannabidiol products remains largely unregulated in the US. Unlike the Rx formulation of CBD [EpidiolexR], little information is available regarding labeling accuracy (does the product contain what the label says it does), lot to lot variability, nor long-term product stability. Understanding these properties are fundamental if these products are to be used in patients with epilepsy, where product variability of traditional AEDs has been suspected to result in inadequate seizure control. Therefore, we analyzed commercial CBD products, including oils, aqueous products (i.e., beverages), and various Other products for cannabinoid content vs label claims and stability under United States Pharmacopeia (USP) standards. METHOD: Samples were diluted and analyzed by HPLC for CBD, THC, and CBN concentrations in order to assess product label accuracy. Products with <90% of label claim CBD were denoted over-labeled, products with >110% of label claim CBD were denoted under-labeled, and products between 90% and 110% of label claim CBD were denoted appropriately labeled, per USP standards. RESULTS: Among commercial CBD Oils (n = 11), mean CBD concentration vs label claim was 91.56% [95% CI, 66.02-117.10%], although 18.18% of oils (n = 2) made nonspecific label claims of "hemp extract" in lieu of CBD. Among all oils, 36.36% (n = 4) were appropriately labeled, another 36.4% (n = 4) of all oils were under-labeled, maximum 128.3% label claim, and finally, 9.09% (n = 1) of oils were over-labeled. The remaining 18.18% (n = 2) of oils lacked specific CBD label claims, minimum of 0.3 mg CBD per 1-ml "dose". THC was detected in 54.55% (n = 6) of oils with a maximum concentration of 0.2% w/v and a minimum concentration of 0.036% w/v. Cannabinol was detectable in only 9.1% (n = 1) of products at a concentration of 0.00465% w/v. Among aqueous products (n = 21) tested, only 66.67% (n = 14) gave specific CBD label claims, with mean CBD concentration vs label claim of 59.93% [95% CI, 38.24-81.63%]. Only 7.14% (n = 1) of aqueous products with a label claim were appropriately labeled, 14.29% (n = 2) were found to be under-labeled, and 78.57% (n = 11) over-labeled. THC was detected in 23.81% (n = 5) of aqueous products tested with a maximum THC concentration of 0.0005% w/v, and a minimum concentration of 0.0002% w/v. Cannabinol was detected in 9.52% (n = 2) of aqueous products, both at a concentration of 0.0015% w/v. "Other" products (n = 7) tested ranged from chocolate bars to transdermal patches. Some 42.86% (n = 3) gave specific CBD label claims, with mean CBD concentration vs label claim of 67.01% [95% CI, 0.87-133.14%]. Among these three "Other" products with specific label claims, 33% (n = 1) was appropriately labeled, and 66.67% (n = 2) were over-labeled, with CBD concentrations vs label claim ranging from a minimum of 39.30% to a maximum of 101.99%. The remaining 57.14% (n = 5) of "Other" products tested made nonspecific CBD label claims, denoting CBD content in terms of "full spectrum hemp extract" or "activated cannabinoids". One such product was labeled with a "40-50-mg CBD" range instead of a single, specific value. Tetrahydrocannabinol was detected in 71.43% (n = 5) of Other products tested with a maximum concentration of 0.0046% w/w, and a minimum concentration of 0.0008% w/w. Cannabinol was detected in 14.3% (n = 1) of Other products at a concentration of 0.0001% w/w. CONCLUSION: We demonstrate that commercial CBD products, especially aqueous beverages, can show inconsistent labeling, vary largely from their label claims should they make them, and show lot-to-lot variability making dosing unpredictable.

Interindividual Variability in the Bioavailability of Gabapentin Enacarbil Extended Release in Healthy Adults: An Analysis of Data From 6 Phase I Studies.

BACKGROUND: The absorption and bioavailability of oral gabapentin are associated with a high degree of interindividual variability. Gabapentin enacarbil, a prodrug of gabapentin, is well absorbed and provides sustained, dose-proportional exposure to gabapentin. The aim of this analysis was to describe the interindividual variability in the bioavailability of gabapentin after gabapentin enacarbil administration in healthy subjects. METHODS: Gabapentin pharmacokinetic (PK) parameters after an oral dose of gabapentin enacarbil 1200 mg (2 600-mg tablets) were compared across 6 phase I studies in healthy adults (n = 12 per study). The distribution of bioavailability values was assessed in all studies. RESULTS: The mean PK parameters of gabapentin were consistent across the trials: maximum concentration range: 6.4-7.9 µg/mL, time to maximum concentration range: 5.2-8.2 hours, area under the plasma-concentration curve extrapolated from time 0 to infinity or at steady state range: 70.8-109.4 µg·h/mL, and bioavailability range: 64.8%-82.9%. Overall, the mean bioavailability was 74.1% (SD, 14.1; coefficient of variation, 19.1%). Individual bioavailability across all studies ranged from 42% to 100%. CONCLUSIONS: Gabapentin PK after gabapentin enacarbil administration was consistent across studies, with low interindividual variability in bioavailability. Gabapentin enacarbil may provide more consistent and predictable exposure to gabapentin than oral gabapentin formulations.

Extending the reach of science - Talk in plain language.

There has been increasing interest by the general public to read and share mainstream medical and scientific literature. Consequently, more and more medical journals are adopting strategies to make complex literature more accessible to the lay public. One such strategy is the creation of so called "lay summaries". The benefits of lay summaries can include wider dissemination of knowledge, and is increasingly being recognized as a unique expertise by authors. While on the surface, it may seem to be an easy task to translate scientific literature into a lay summary. However, occasionally authors who are experienced in communicating complex information to a peer group, may struggle with translating their work to an audience with limited medical or scientific background. The objective of this review is to discuss strategies that scientific writers may consider to better facilitate translating scientific literature into lay summaries.

Levetiracetam-associated irritability and potential role of vitamin B6 use in veterans with epilepsy.

OBJECTIVES: Levetiracetam, a commonly prescribed antiseizure medication (ASM), may cause irritability, depression, and anger. The mechanisms underlying these behavioral effects and individual risk factors remain unknown. Mitigation strategies are limited, including discontinuation, supplementation with vitamin B6, or switching to an alternative ASM. Several retrospective studies and anecdotal reports, primarily in pediatric populations, suggest vitamin B6 supplementation may be helpful in reducing levetiracetam-associated irritability. Although data in adult patients is limited, and no data is available for Veterans. The objective of this project was to describe our preliminarily experience with vitamin B6 supplementation for alleviating levetiracetam-associated irritability in male Veterans with epilepsy. METHODS: Retrospective chart reviews were completed for patients who had an active prescription for levetiracetam from the William S. Middleton Memorial Veterans Hospital from January 1, 2015 to June 1, 2020. A total of 26 charts were screened. Patients were excluded if not using vitamin B6 supplementation or if deceased at end of data collection. Baseline characteristics were compared, including age, sex, comorbidities, and concomitant medications. Charts were then reviewed to identify any clinical description of irritability, including subjective assessment of change in symptoms across multiple visits, and scores from standardized instruments including the patient health questionnaire (PHQ-9), generalized anxiety disorder questionnaire (GAD-7), and/or irritability in adult patients with epilepsy (I-EPI) questionnaire. These symptoms and scores were then compared pre- and post-B6 supplementation. RESULTS: Of 22 patients, data was available for 20 (91%). For patients with data available, 9 (45%) showed improved irritability following supplementation with vitamin B6 and 11 (55%) showed no improvement. CONCLUSIONS: This project suggests that vitamin B6 supplementation may have a role in mitigating levetiracetam-associated irritability in a male Veteran population. These results support future prospective controlled studies to assess further the efficacy of this approach and characteristics associated with successful treatment in veterans.

Use of extended-release and immediate-release anti-seizure medications with a long half-life to improve adherence in epilepsy: A guide for clinicians.

Poor adherence to anti-seizure medications (ASMs) is associated with breakthrough seizures and potentially increased toxicity in patients with epilepsy. Extended-release (ER) drugs and immediate-release (IR) drugs with a long half-life (t1/2) that permit once-daily dosing (such as, perampanel, zonisamide, lamotrigine [IR, ER] and topiramate [ER]) have a number of advantages over short t1/2 ASMs that require multiple daily dosing. These advantages include simplification of dosing regimens, reduction in pill burden, and a decrease in the peak-to-trough fluctuations in serum drug concentration that may be associated with a decreased risk of adverse effects and seizures. Such properties have wider implications in improving patient adherence to treatment. This article is intended as a practical guide for clinicians that provides an overview of the features of ER ASMs and long t1/2 IR ASMs that are advantageous in the context of patient adherence and pharmacokinetic "forgiveness" (after missing a dose). In addition, we note that efforts to improve adherence should not depend solely on drug dosing regimens and drug pharmacokinetics, but should be part of a wider strategy that includes therapeutic drug monitoring, improved healthcare provider-patient dialogue, patient education, and the use of "reminder" technology.