Seizure frequency, quality of life, behavior, cognition, and sleep in pediatric patients enrolled in a prospective, open-label clinical study with cannabidiol

Real-world experience of cannabidiol in conjunction with clobazam for the treatment of seizures associated with Lennox-Gastaut syndrome and Dravet syndrome: Results from a retrospective multicentre chart review in Germany

BACKGROUND

Lennox-Gastaut syndrome (LGS) and Dravet syndrome (DS) are rare and debilitating forms of epilepsy, characterised by recurrent, severe, drug-resistant seizures and neurodevelopmental impairments. A non-euphoric, plant-derived, highly purified formulation of cannabidiol (CBD; Epidyolex®, 100 mg/mL oral solution) is approved in the European Union and United Kingdom for use in patients aged ≥2 years for the adjunctive treatment of seizures associated with LGS or DS in conjunction with clobazam (CLB), and for the adjunctive treatment of seizures associated with tuberous sclerosis complex in patients aged ≥2 years.

METHODS

We performed a retrospective chart review of patients with treatment-resistant epilepsies who were treated with adjunctive CBD at six epilepsy centres in Germany. We analysed patient and treatment characteristics, seizure outcomes, treatment retention rates (i.e. the proportion of patients remaining on CBD treatment at time of assessment and retention as estimated by Kaplan-Meier [KM] analyses), physician-rated Clinical Global Impression of Change (CGI-C), and adverse events (AEs) for up to 12 months. Here, we report data from this chart review for those patients with LGS or DS receiving adjunctive treatment with concomitant CBD and CLB.

RESULTS

We identified 126 patients (102 LGS; 24 DS) receiving CBD and CLB, with a mean (standard deviation [SD]) age of 23.2 (15.8) years and a mean (SD) age of epilepsy onset of 3 (3.7) years. Patients had received a median (range) number of prior antiseizure medications (ASMs) of 6 (1-24) and concomitant ASMs of 3 (1-7). The median target CBD dose was 11.1 mg/kg/day in the total population (17.8, 15.8, and 9.7 mg/kg/day in the <6 years, 6-17 years, and ≥18 years subgroups, respectively). The median time to the target dose was 21-22 days across age groups. The median concomitant CLB dose was 0.14 mg/kg/day (0.38, 0.22, and 0.10 mg/kg/day in the respective age groups). A ≥50% reduction in total seizures was observed in 47.5% of patients at 3 months (35.7-52.6% across age groups) and 45.5% of patients at 12 months (44.4-46.2% across age groups). For generalised tonic-clonic seizures, a ≥50% reduction was observed in 63.0% of patients at 3 months (60.7-66.7% across age groups) and 56.9% of patients at 12 months (50.0-75.0% across age groups). Median seizure days per month significantly decreased from 30 (range: 0.5-30) at baseline to 15 (range: 0-30) at the last follow-up (p <0.001). Overall, 89.7%, 80.7%, and 69.8% patients remained on CBD at 3, 6, and 12 months, respectively. KM estimated treatment retention was similar across paediatric and adult groups, according to earlier or later initiation (e.g. ≤4 vs ≥15 prior and concomitant ASMs) and according to the syndrome (LGS and DS). Physicians rated 66% of patients demonstrated a CGI-C improvement and 67% demonstrated a CGI-C behaviour improvement. The most common AEs (≥5%) were sedation (n = 30, 23.8%), diarrhoea (n = 13, 10.3%) and psycho-behavioural AEs (n = 9, 7.1%).

CONCLUSION

In this chart review of patients with severe treatment refractory LGS or DS receiving adjunctive CBD and CLB concomitantly, a reduction in seizure frequency and sustained treatment retention was observed for up to 12 months across age groups in real-world clinical practice. CBD discontinuations exclusively due to AEs were infrequent and the AE profile was generally aligned to that previously observed.

Cannabidiol prescribing in the United States: An analysis of real-world data

Background

Off-label prescribing of Epidiolex® (pharmaceutical cannabidiol) comes with both potential benefits and risks for patients. The aims of this study were to: (1) identify the percentage of people prescribed Epidiolex® who do not have diagnostic indications for Epidiolex® (Lennox Gastaut Syndrome [LGS], Dravet Syndrome [DS], and Tuberous Sclerosis Complex [TSC]) and (2) examine potential co-prescribing of medications that may interact with Epidiolex®.

Method

Using TriNetX analytics, a web-based database of de-identified electronic health records spanning >110 million people in the United States, we analyzed 4214 people receiving Epidiolex® in 2022. We computed the number of people prescribed Epidiolex® who did not have diagnoses for LGS, DS, or TSC. We evaluated the prevalence of co-occurring prescriptions that are known to interact with cannabidiol following each individual's first Epidiolex® prescription.

Results

Among individuals receiving Epidiolex®, 40 % did not have FDA-approved diagnostic indications (LGS/DS/TSC) in the medical record. In the overall sample, co-occurring psychotropic prescribing was prevalent, including medications with known interactions with cannabidiol (Clobazam=47.2 %; Diazepam=47.4 %; Clonazepam=40.7 %). Among individuals without LGS/DS/TSC who received Epidiolex®, the most common diagnoses received following the index prescription were unspecified epileptic syndromes (53.8 %), sleep disorders (25.7 %), anxiety disorders (25.9 %), mood disorders (18.6 %) and autism spectrum disorders (10.8 %).

Conclusion

Off-label prescribing and co-prescription of medications with known interactions with cannabidiol is prevalent. Further research is needed to elucidate longitudinal outcomes associated with off-label Epidiolex® prescribing.

Cannabidiol Supplements in Romania: Bridging the Gap Between Marketed Claims and Clinical Reality

In recent years, the European market, including Romania, has witnessed a significant increase in the promotion of cannabidiol (CBD)-based products, often presented as effective treatments for various health conditions. This study investigates the inconsistencies between the health claims associated with these supplements and the evidence from clinical trials. To identify products available on the Romanian market, a systematic review of online pharmacies and websites that specialize in selling CBD-based products has been performed. Additionally, a systematic review of clinical trials has been conducted to assess the efficacy of CBD for the specified indications. Our analysis revealed that some claims, such as those related to post-traumatic stress disorder, lack substantial clinical evidence. Moreover, even when clinical support exists, the dosages recommended for the supplements are often significantly lower than those used in trials, raising concerns about their efficacy. These findings highlight the need for stricter regulatory oversight and more transparent communication to ensure that consumer expectations are aligned with scientific evidence, ultimately promoting informed decision-making and consumer safety.

Long-term outcomes and adaptive behavior in adult patients with Lennox-Gastaut syndrome

OBJECTIVE

Lennox-Gastaut syndrome (LGS) is a severe form of epilepsy characterized by difficult-to-control seizures and cognitive dysfunction. Previous studies mainly focused on pediatric populations, and little is known about the long-term cognitive outcome in adult patients with LGS. The objective of this study was to investigate the long-term functional and adaptive behavior in adult patients with LGS.

METHODS

This cross-sectional study enrolled adult patients diagnosed with LGS according to the recently published International League Against Epilepsy (ILAE) diagnostic criteria. The adaptive behavior of participants was assessed using the Vineland Adaptive Behavior Scales, Survey Interview, Second Edition (VABS-II). Demographic, clinical, electroencephalography (EEG), and antiseizure medication (ASM) data were also collected at different timepoints, to investigate their association with VABS-II scores.

RESULTS

The study included 38 adult patients with LGS. A low score on the Adaptive Behavior Composite Scale was found in all patients. When considering single VABS-II domains, particularly low scores were found in daily living skills and socialization, whereas slightly higher performances were observed in communication. An earlier age at LGS diagnosis was identified as the most significant predictor of worse adaptive outcomes in adult life. At the time of study evaluation, high seizure frequency, higher EEG background slowing, and multifocal EEG epileptiform abnormalities were significantly associated with lower VABS-II raw scores. Furthermore, in an exploratory correlation analysis with ASM regimen at the study visit, treatment with cannabidiol was associated with higher adaptive behavior scores, whereas benzodiazepine intake correlated with lower scores.

SIGNIFICANCE

This study provides relevant insights into the long-term challenges faced by adults with Lennox-Gastaut syndrome (LGS), highlighting significant impairments in adaptive behavior as well as the associated clinical and electroencephalography features. Additionally, this study provides a more specific neuropsychological profile in adults with LGS and underscores the importance of comprehensive care approaches that go beyond seizure control in this population.

PLAIN LANGUAGE SUMMARY

This study examined adults with Lennox-Gastaut syndrome (LGS), a severe type of epilepsy, to understand their long-term abilities to perform daily tasks and adapt socially. We found that these adults have significant difficulties with daily living and social skills, although not all areas were equally affected. They performed somewhat better in communication, particularly in understanding others (receptive communication). Importantly, the younger the age at which LGS was diagnosed, the worse their outcomes were as adults. This study highlights the need for research and treatment approaches that focus not only on controlling seizures but also on improving daily life skills.

Medical cannabis for children: Evidence and recommendations

Interest in using cannabis products for a medical purpose in children under the age of 18 years is increasing. There are many medical cannabis products available that can include cannabidiol (CBD) or delta-9-tetrahydrocannabinol (THC), or both. Despite many therapeutic claims, there are few rigorous studies to inform the dosing, safety, and efficacy of medical cannabis in paediatric clinical practice. This statement reviews the current evidence and provides recommendations for using medical cannabis in children. Longer-term (2-year) reports support the sustained tolerability and efficacy of cannabidiol therapy for patients with Lennox-Gastaut and Dravet syndromes. CBD-enriched cannabis extracts containing small amounts of THC have been evaluated in a small number of paediatric patients, and further research is needed to inform clinical practice guidelines. Given the widespread use of medical cannabis in Canada, paediatricians should be prepared to engage in open, ongoing discussions with families about its potential benefits and risks, and develop individualized plans that monitor efficacy, reduce harms, and mitigate drug-drug interactions.

Les données probantes et les recommandations sur le cannabis à des fins médicales chez les enfants

L'intérêt envers l'utilisation des produits du cannabis à des fins médicales chez les enfants de moins de 18 ans augmente. De nombreux produits du cannabis à des fins médicales contiennent du cannabidiol, du delta-9-tétrahydrocannabinol ou ces deux produits. Malgré les nombreuses prétentions thérapeutiques, peu d'études rigoureuses guident la posologie, l'innocuité et l'efficacité du cannabis à des fins médicales en pédiatrie clinique. Le présent document de principes passe en revue les données probantes à jour et expose les recommandations sur l'utilisation du cannabis à des fins médicales chez les enfants. Les rapports à plus long terme (deux ans) souscrivent à la tolérabilité et à l'efficacité soutenues d'un traitement au cannabidiol chez les patients ayant le syndrome de Lennox-Gastaut ou le syndrome de Dravet. Les extraits de cannabis enrichis de cannabidiol qui renferment de petites quantités de delta-9-tétrahydrocannabinol ont été évalués auprès d'un petit nombre de patients d'âge pédiatrique, et d'autres recherches devront être réalisées pour éclairer les guides de pratique clinique. Étant donné l'utilisation répandue du cannabis à des fins médicales au Canada, les pédiatres devraient être prêts à participer à des échanges ouverts et continus avec les familles au sujet de ses avantages potentiels et de ses risques, ainsi qu'à préparer des plans individuels en vue d'en surveiller l'efficacité, de réduire les méfaits et de limiter les interactions médicamenteuses.

Mediating effects of sleep quality between clinical characteristics and quality of life in children with epilepsy: A cross-sectional study from Southwest China

BACKGROUND

Although sleep quality (SQ) reportedly affects the health-related quality of life (QOL) of patients with epilepsy, little is known about the potential association between SQ and QOL, particularly in children with epilepsy (CWE). Our study aimed to investigate the mediating effect of SQ on the QOL of CWE to obtain more information for the prevention and treatment of epilepsy in children.

METHODS

We collected general demographic and clinical data of 212 CWE and 79 controls (children who visited the Health Examination Department), and their guardians were instructed to answer the Children's Sleep Habits Questionnaire (CSHQ) and the optimized Quality of Life in Childhood Epilepsy Questionnaire-16 (QOLCE-16). The t-test, analysis of variance, chi-square test, and Fisher's exact test were used for between group comparisons. The Pearson correlation was used to analyze the correlation between variables. The direct, indirect, and total effects of predictors on the QOL of CWE were estimated based on an adjusted mediation model.

RESULTS

CWE had significantly smaller long-term urban residence rates, less educated guardians, higher total CSHQ score, higher incidence of poor SQ, higher bedtime resistance, more sleep anxiety, worse sleep-disordered breathing, increased parasomnia, more daytime sleepiness, more frequent night waking, and greater sleep onset delay than controls (P < 0.05 for all). The univariable analysis showed significant differences in total CSHQ scores between CWE with different seizure frequency in the last month, whether or not drug-resistant epilepsy (DRE), and with different video electroencephalogram (VEEG) findings (P < 0.05 for all). Differences in QOLCE-16 scores between CWE with different guardian's employment status, age at diagnosis, number of anti-seizure medication (ASM) types, seizure frequency in the last month, DRE status, seizure type, VEEG findings, neuropsychological evaluation findings, magnetic resonance imaging (MRI) findings, and etiology were statistically significant (P < 0.05 for all). The correlation study indicated that the total CSHQ score was negatively correlated with the QOLCE-16 score (P < 0.05). The mediation analysis showed that DRE and VEEG abnormalities had a standardized direct effect on the QOL. Seizure frequency in the last month, DRE, and VEEG abnormalities had an indirect effect on the QOL through SQ, and their mediating effect values of SQ were 31.61 %, 13.45 %, and 14.35 %, respectively.

CONCLUSION

Our findings uncovered the relationship of some clinical characteristics with SQ and QOL and characterized the nature of factors affecting the QOL of CWE. SQ could be a key factor in the prognosis of CWE experiencing epileptic seizures, and more attention should be paid on the management of SQ in interventions for epilepsy.

Caregiver-reported outcomes with real-world use of cannabidiol in Lennox-Gastaut syndrome and Dravet syndrome from the BECOME survey

PURPOSE

Plant-derived highly purified cannabidiol (CBD) reduced the frequency of seizures associated with Lennox-Gastaut syndrome (LGS) and Dravet syndrome (DS) and improved the overall condition of patients in placebo-controlled phase 3 clinical trials. Anecdotal reports also suggest a positive effect on nonseizure outcomes. In this study, we aimed to identify, through a caregiver survey which nonseizure outcomes were most likely to change in these patients.

METHODS

The BEhavior, COgnition, and More with Epidiolex® (BECOME) was a 20-minute, cross-sectional, online survey that was developed with extensive input from caregivers, healthcare professionals, and epilepsy researchers, and was based on questions from validated measures and previously published caregiver reports. US-based caregivers (from Jazz Pharmaceuticals patient/caregiver database) of people with LGS or DS who were treated with CBD (Epidiolex®, 100 mg/mL oral solution) for ≥3 months were asked to compare the past month to the period before CBD initiation and rate their impression of changes using symmetrical Likert scales.

RESULTS

A total of 498 caregivers (97% parents) of patients with LGS (80%) or DS (20%) completed the survey. Mean (range) age of patients was 16 (1-73) years, and 52% were male. Patients were taking a median CBD dose of 14 mg/kg/d and median 4 concomitant antiseizure medications. A large proportion of respondents reported improvements in ≥1 survey question for all nonseizure-related domains: alertness, cognition, and executive function (85%); emotional functioning (82%); language and communication (79% in nonverbal patients and 74% in verbal); activities of daily living (51%); sleep (51%); and physical functioning (46%). Respondents reported improvements in seizure-related domains, including overall seizure frequency (85%), overall seizure severity (76%), seizure-free days per week for ≥1 seizure type (67%), and seizure freedom during the past month (16%). The majority of respondents who reported reduction in seizure frequency also reported improvements in nonseizure outcomes domains (51-80%). However, improvements in nonseizure outcomes (18-56%) were also reported in patients who either had no change or worsening of seizure frequency.

CONCLUSIONS

This survey characterized and quantified caregiver impression of changes in the seizure and nonseizure outcomes in patients taking add-on CBD treatment. Overall, 93% of caregivers reported planning to continue CBD treatment, primarily because of reduced seizure burden but also because of improvements in nonseizure-related outcomes. Despite the limitations that are associated with a retrospective survey-based study design, these results support further evaluation of the effect of CBD treatment on nonseizure outcomes among patients with LGS or DS.

Long-term efficacy and adverse effects of cannabidiol in adjuvant treatment of drug-resistant epilepsy: a systematic review and meta-analysis

Background

Epilepsy is one of the most common chronic brain diseases. Almost one-third of patients have drug-resistant epilepsy (DRE). Cannabidiol is being considered as a potential novel drug for treating DRE.

Objectives

To investigate long-term efficacy and safety of cannabidiol in treatment of DRE and the differences in cannabidiol treatment among patients with different characteristics.

Design

Systematic review and meta-analysis.

Data sources and methods

Medline, Embase, and CENTRAL were searched for literature. RevMan5.4 was used for meta-analysis. The Intention-to-treat set and the random effect were used as the main analysis. Subgroup analyses were performed according to age, dose, concomitant antiseizure medications (ASMs), epilepsy syndromes, and study designs.

Results

Fifty studies were included in this systematic review. A total of 4791 participants were collected. The responder rates (seizure frequency reduced at least 50%) at 12-, 24-, 48-, 72-, 96-, and 144-week were 0.40 [0.36, 0.45], 0.39 [0.34, 0.44], 0.37 [0.30, 0.44], 0.27 [0.17, 0.37], 0.22 [0.14, 0.30], and 0.38 [0.23, 0.53]. Seizure-free rates were 0.04 [0.03, 0.06], 0.04 [0.03, 0.05], 0.03 [0.02, 0.05], 0.03 [0.02, 0.03], 0.02 [0.01, 0.03], and 0.04 [0.01, 0.06]. Proportion of adverse events were 0.72 [0.61, 0.83], 0.62 [0.42, 0.81], 0.60 [0.41, 0.79], 0.35 [0.14, 0.56], 0.83 [0.75, 0.90], and 0.96 [0.94, 0.99]. The pooled 12-, 24-, 48-, 96-, and 144-week proportion of serious adverse events were 0.15 [0.09, 0.21], 0.23 [0.14, 0.31], 0.10 [0.06, 0.15], 0.31 [0.24, 0.38], and 0.40 [0.35, 0.45]. Subgroup analyses showed that there was no significant difference on efficacy and safety among age subgroups and epilepsy syndromes subgroups. For most periods, there were no significant difference on efficacy among subgroups of dose and concomitant ASMs. However, higher doses and more concomitant ASMs were associated with higher proportion of adverse events.

Conclusion

Cannabidiol treatment of DRE has stable efficacy and fewer adverse events in early period. Long-term use may have decreased efficacy and increased adverse events. Dose escalation may not increase efficacy, but may increase adverse events. Furthermore, cannabidiol use may reduce dosage of other ASMs without reducing efficacy, thereby reducing adverse effects. Cannabidiol may have similar effects in various epilepsy syndromes.

Trial registration

PROSPERO (CRD42022351250).

Highly purified cannabidiol in the treatment of drug-resistant epilepsies: A real-life impact on seizure frequency, quality of life, behavior, and sleep patterns from a single Italian center

Seizure frequency in treatment-resistant epilepsies seems to be decreased by cannabidiol (CBD), but contrasting data are available on its effect on sleep, behavior, and quality of life (QoL), and no data is reported on its effect on parental stress in patients with epilepsy (PWE). Thus, we conducted a retrospective study on a cohort of children and adults with drug-resistant epilepsy (DRE) who had been treated with highly purified, pharmaceutical-grade CBD to evaluate its effects on seizure frequency, QoL, behavior, parental stress, and sleep. Eighteen patients (12 adults and 6 children) were included in the cohort and followed for a median of 9 months. At the last follow-up (Tn), nine patients (50%) were considered CBD responders with at least a 50% decrease in seizure frequency. No serious adverse effects were found. No statistically significant differences were found concerning sleep, including daytime sleepiness, and no statistically significant effect was found on parental stress at Tn. An improvement was found for social interaction in quality of life (p < 0.05) for all patients. Our results demonstrate that CBD is a safe and effective antiseizure medication (ASM). CBD doesn't seem to affect sleep measures in adults and children or worsen daytime sleepiness. However, CBD improves specific QoL measures, which could indicate a possible use of CBD for other childhood disabilities. No impact of CBD was seen on parental stress, which could possibly be due to the limited follow-up or could mean that parental stress is not dependent on seizure frequency.

The therapeutic potential of purified cannabidiol

The use of cannabidiol (CBD) for therapeutic purposes is receiving considerable attention, with speculation that CBD can be useful in a wide range of conditions. Only one product, a purified form of plant-derived CBD in solution (Epidiolex), is approved for the treatment of seizures in patients with Lennox-Gastaut syndrome, Dravet syndrome, or tuberous sclerosis complex. Appraisal of the therapeutic evidence base for CBD is complicated by the fact that CBD products sometimes have additional phytochemicals (like tetrahydrocannabinol (THC)) present, which can make the identification of the active pharmaceutical ingredient (API) in positive studies difficult. The aim of the present review is to critically review clinical studies using purified CBD products only, in order to establish the upcoming indications for which purified CBD might be beneficial. The areas in which there is the most clinical evidence to support the use of CBD are in the treatment of anxiety (positive data in 7 uncontrolled studies and 17 randomised controlled trials (RCTs)), psychosis and schizophrenia (positive data in 1 uncontrolled study and 8 RCTs), PTSD (positive data in 2 uncontrolled studies and 4 RCTs) and substance abuse (positive data in 2 uncontrolled studies and 3 RCTs). Seven uncontrolled studies support the use of CBD to improve sleep quality, but this has only been verified in one small RCT. Limited evidence supports the use of CBD for the treatment of Parkinson's (3 positive uncontrolled studies and 2 positive RCTs), autism (3 positive RCTs), smoking cessation (2 positive RCTs), graft-versus-host disease and intestinal permeability (1 positive RCT each). Current RCT evidence does not support the use of purified oral CBD in pain (at least as an acute analgesic) or for the treatment of COVID symptoms, cancer, Huntington's or type 2 diabetes. In conclusion, published clinical evidence does support the use of purified CBD in multiple indications beyond epilepsy. However, the evidence base is limited by the number of trials only investigating the acute effects of CBD, testing CBD in healthy volunteers, or in very small patient numbers. Large confirmatory phase 3 trials are required in all indications.

Psychobehavioural and Cognitive Adverse Events of Anti-Seizure Medications for the Treatment of Developmental and Epileptic Encephalopathies

The developmental and epileptic encephalopathies encompass a group of rare syndromes characterised by severe drug-resistant epilepsy with onset in childhood and significant neurodevelopmental comorbidities. The latter include intellectual disability, developmental delay, behavioural problems including attention-deficit hyperactivity disorder and autism spectrum disorder, psychiatric problems including anxiety and depression, speech impairment and sleep problems. Classical examples of developmental and epileptic encephalopathies include Dravet syndrome, Lennox-Gastaut syndrome and tuberous sclerosis complex. The mainstay of treatment is with multiple anti-seizure medications (ASMs); however, the ASMs themselves can be associated with psychobehavioural adverse events, and effects (negative or positive) on cognition and sleep. We have performed a targeted literature review of ASMs commonly used in the treatment of developmental and epileptic encephalopathies to discuss the latest evidence on their effects on behaviour, mood, cognition, sedation and sleep. The ASMs include valproate (VPA), clobazam, topiramate (TPM), cannabidiol (CBD), fenfluramine (FFA), levetiracetam (LEV), brivaracetam (BRV), zonisamide (ZNS), perampanel (PER), ethosuximide, stiripentol, lamotrigine (LTG), rufinamide, vigabatrin, lacosamide (LCM) and everolimus. Bromide, felbamate and other sodium channel ASMs are discussed briefly. Overall, the current evidence suggest that LEV, PER and to a lesser extent BRV are associated with psychobehavioural adverse events including aggressiveness and irritability; TPM and to a lesser extent ZNS are associated with language impairment and cognitive dulling/memory problems. Patients with a history of behavioural and psychiatric comorbidities may be more at risk of developing psychobehavioural adverse events. Topiramate and ZNS may be associated with negative effects in some aspects of cognition; CBD, FFA, LEV, BRV and LTG may have some positive effects, while the remaining ASMs do not appear to have a detrimental effect. All the ASMs are associated with sedation to a certain extent, which is pronounced during uptitration. Cannabidiol, PER and pregabalin may be associated with improvements in sleep, LTG is associated with insomnia, while VPA, TPM, LEV, ZNS and LCM do not appear to have detrimental effects. There was variability in the extent of evidence for each ASM: for many first-generation and some second-generation ASMs, there is scant documented evidence; however, their extensive use suggests favourable tolerability and safety (e.g. VPA); second-generation and some third-generation ASMs tend to have the most robust evidence documented over several years of use (TPM, LEV, PER, ZNS, BRV), while evidence is still being generated for newer ASMs such as CBD and FFA. Finally, we discuss how a variety of factors can affect mood, behaviour and cognition, and untangling the associations between the effects of the underlying syndrome and those of the ASMs can be challenging. In particular, there is enormous heterogeneity in cognitive, behavioural and developmental impairments that is complex and can change naturally over time; there is a lack of standardised instruments for evaluating these outcomes in developmental and epileptic encephalopathies, with a reliance on subjective evaluations by proxy (caregivers); and treatment regimes are complex involving multiple ASMs as well as other drugs.

A scoping review on cannabidiol therapy in tuberous sclerosis: Current evidence and perspectives for future development

Cannabidiol (CBD) has recently been approved as an add-on therapy by various regulatory agencies for tuberous sclerosis complex (TSC)-associated seizures based on its short-term efficacy and safety in a pivotal randomized controlled trial. However, critical information about which patients with TSC and seizure types respond best to CBD (clinical, electrophysiological, and genetic predictors of responsiveness), when to use CBD in the treatment algorithm, and how CBD can be combined with other antiseizure medications (ASMs) in the form of a rational polypharmacy therapy is still lacking. In general, there is a limited in-depth critical review of CBD for the treatment of TSC to facilitate its optimal use in a clinical context. Here, we utilized a scoping review approach to report the current evidence of efficacy and safety of pharmaceutical-grade CBD in patients with TSC, including relevant mechanism of action and drug-drug interactions with other ASMs. We also discussed emerging information about CBD's long-term efficacy and safety data in patients with TSC. Finally, we discussed some critical unanswered questions in several domains related to effective clinical management of TSC using CBD, including barriers to early and aggressive treatment in infants, difficulty with universal access to CBD, a lack of studies to understand CBD's impact on seizure severity and specific seizure types, insufficient exploration of CBD in TSC-related cognitive and behavioral issues, and the need for more research into CBD's effects on various biomarkers.