Systemic disease manifestations associated with epilepsy in tuberous sclerosis complex

Long-term efficacy and safety of cannabidiol in patients with tuberous sclerosis complex: 3-year results from the cannabidiol expanded access program

OBJECTIVE

The cannabidiol (CBD) Expanded Access Program provided compassionate access to CBD for patients with treatment-resistant epilepsy, including tuberous sclerosis complex (TSC), at 35 US epilepsy centers. Here, we present the long-term efficacy and safety outcomes for add-on CBD treatment in patients with TSC.

METHODS

Patients received plant-derived, highly purified CBD (Epidiolex® 100 mg/mL, oral solution), increasing from 2 to 10 mg/kg/d to tolerance or maximum of 25-50 mg/kg/d. Efficacy endpoints were percentage change from baseline in median monthly convulsive, focal, and total seizure frequency and ≥ 50%, ≥75%, and 100% responder rates across 12-week visit windows through 144 weeks. Adverse events (AEs) are reported through 233 weeks.

RESULTS

Thirty-four patients with confirmed TSC were included. Mean age was 12.4 years (range, 1.8-31.2), and patients were receiving a median of 3 (range, 1-7) antiseizure medications (ASMs) at baseline. Median CBD dose was 25-28 mg/kg/d for 36 weeks and then 20-50 mg/kg/d through 228 weeks. Dose reduction from baseline occurred for most ASMs, except topiramate. Median reduction in the frequency of convulsive, focal, and total seizures was 44%-81%, 51%-87%, and 44%-87%, respectively, through 144 weeks. Responder rates (≥50%, ≥75%, and 100% reduction) were 43%-71%, 14%-58%, and 0%-25% for convulsive seizures; 52%-75%, 35%-60%, and 7%-32% for focal seizures; and 46%-79%, 26%-65%, and 0%-13% for total seizures. A total of 94% of patients experienced ≥1 AE; 47% had serious AEs, considered treatment unrelated by the investigator. Treatment-related AEs (TRAEs) occurred in 71% of patients. The most frequently reported TRAEs were somnolence, diarrhea, and ataxia. Two patients experienced AEs leading to discontinuation. There were no deaths.

SIGNIFICANCE

Long-term add-on CBD use was associated with reduced seizure frequency through 144 weeks. The safety profile was consistent with previous reports.

PLAIN LANGUAGE SUMMARY

In this study, we evaluated efficacy and safety of cannabidiol (CBD) treatment in patients with tuberous sclerosis complex receiving CBD in addition to other antiseizure treatments in an Expanded Access Program. After starting CBD, 46%-79% of patients had at least 50% reduction and 26%-65% had at least 75% reduction in the number of seizures per month; up to 13% had no seizures through 144 weeks. Safety results were similar to prior studies; sleepiness and diarrhea were common treatment-related side effects. These results show that long-term CBD treatment was associated with fewer seizures and mild/moderate side effects.

Have epilepsy outcomes changed for children with tuberous sclerosis complex in Queensland, Australia?

OBJECTIVE

Historically, epilepsy has been the most frequently presenting feature of tuberous sclerosis complex (TSC). Advances in TSC health care have occurred over the past decade; thus, we studied whether TSC epilepsy outcomes have changed.

METHOD

A retrospective chart review was undertaken for all children with TSC in Queensland, Australia. Epilepsy outcome and TSC diagnosis data were extracted, and data were compared between children born before 2012 with those born in or after 2012.

RESULTS

In this retrospective cohort, TSC diagnosis in children born in or after 2012 is now predominantly antenatal (51%, p < .05). Most patients with epilepsy are now known to have TSC before they develop epilepsy. Despite earlier TSC diagnosis, the frequency of epilepsy (85%) has not changed (p = .92), but diagnosis trends toward an earlier age (median = 3 months for patients born in or after 2012 vs. 5.5 months for those born before 2012, p = .23). Most (95%) patients had focal seizures as their initial clinical seizure type; it was rare (5%) for epileptic spasms (ES) to be the initial seizure type. The frequency of ES was lower in patients born in or after 2012 (36% vs. 50%, p = .27). Infantile (<24 months) onset ES was not associated with worse epilepsy outcome. Late onset ES was seen in 14%, and these patients had a lower rate of epilepsy remission. Lennox-Gastaut syndrome was seen in 7%. Febrile/illness-related status epilepticus occurred in 12% of patients, between 1 and 4 years of age. Despite many (78%) patients having multiple daily seizures at maximal seizure frequency, and 74% meeting criteria for treatment-refractory epilepsy, most patients achieved epilepsy remission (66%), either with epilepsy surgery (47%) or with age (53%). At the time of inclusion in this study, only 21% of patients had uncontrolled frequent (daily to 3 monthly) seizures and 14% had uncontrolled infrequent (3 monthly to <2 yearly) seizures.

SIGNIFICANCE

This study provides updated information that informs the counseling of parents of newly diagnosed pediatric TSC patients.

Epileptic spasms are associated with increased stereo-electroencephalography derived functional connectivity in tuberous sclerosis complex

OBJECTIVE

Epileptic spasms (ES) are common in tuberous sclerosis complex (TSC). However, the underlying network alterations and relationship with epileptogenic tubers are poorly understood. We examined interictal functional connectivity (FC) using stereo-electroencephalography (SEEG) in patients with TSC to investigate the relationship between tubers, epileptogenicity, and ES.

METHODS

We analyzed 18 patients with TSC who underwent SEEG (mean age = 11.5 years). The dominant tuber (DT) was defined as the most epileptogenic tuber using the epileptogenicity index. Epileptogenic zone (EZ) organization was quantitatively separated into focal (isolated DT) and complex (all other patterns). Using a 20-min interictal recording, FC was estimated with nonlinear regression, h² . We calculated (1) intrazone FC within all sampled tubers and normal-appearing cortical zones, respectively; and (2) interzone FC involving connections between DT, other tubers, and normal cortex. The relationship between FC and (1) presence of ES as a current seizure type at the time of SEEG, (2) EZ organization, and (3) epileptogenicity was analyzed using a mixed generalized linear model. Spike rate and distance between zones were considered in the model as covariates.

RESULTS

Six patients had ES as a current seizure type at time of SEEG. ES patients had a greater number of tubers with a fluid-attenuated inversion recovery hypointense center (p < .001), and none had TSC1 mutations. The presence of ES was independently associated with increased FC within both intrazone (p = .033) and interzone (p = .011) networks. Post hoc analyses identified that increased FC was associated with ES across tuber and nontuber networks. EZ organization and epileptogenicity biomarkers were not associated with FC.

SIGNIFICANCE

Increased cortical synchrony among both tuber and nontuber networks is characteristic of patients with ES and independent of both EZ organization and tuber epileptogenicity. This further supports the prospect of FC biomarkers aiding treatment paradigms in TSC.

Epidemiology and disease burden of tuberous sclerosis complex in France: A population-based study based on national health insurance data

OBJECTIVE

Tuberous sclerosis complex (TSC) is a rare multisystem disorder, often associated with epilepsy. This retrospective study aimed to identify patients with TSC, including those with epilepsy, from a French healthcare claims database, and to report incidence, prevalence, and healthcare costs and resource utilization.

METHODS

The anonymized French health insurance database (SNDS) covers almost the entire French population. Patients with TSC were identified as having ≥1 International Classification of Diseases, Tenth Revision (ICD-10) diagnosis code Q85.1 or a long-term disease (LTD) registration over the inclusion period (2006-2017). Patients with an ICD-10 epilepsy code or who were dispensed ≥1 antiseizure medication (ASM) in the same year or after their TSC diagnosis were identified as having TSC with epilepsy. Newly diagnosed patients over the inclusion period constituted the incident cohort. Healthcare costs (patients with recorded costs only), healthcare resource use, and ASM dispensation are reported for patients with 2018 data.

RESULTS

In 2018, 3139 prevalent patients with TSC were identified (crude prevalence, 4.69 per 100 000); the incident cohort comprised 2988 patients (crude incidence, 0.44 per 100 000). Among patients with TSC, 67% (2101/3139) had epilepsy (mean [standard deviation, SD] age: 28.8 [18.8] years; male: 48%). Among patients with epilepsy, total mean (SD) annual healthcare costs were €11 413 (27 620) per capita (outpatient, 63%; inpatient, 37%), 46% were hospitalized during 2018 (mean [SD]: 1.8 [10.9] acute care visits per patient), and 65% visited a hospital specialist. Among patients with epilepsy, medication (mean [SD]: €4518 [12 102] per capita) was the greatest contributor (63%) to outpatient costs, and in 2018, 74% were dispensed ≥1 different ASM and 9% were dispensed ≥4 ASMs.

SIGNIFICANCE

TSC with epilepsy was associated with substantial healthcare costs and resource utilization, particularly outpatient and medication costs. Many patients with TSC with epilepsy were prescribed multiple ASMs, suggesting refractory epilepsy.

miRNAs and isomiRs: Serum-Based Biomarkers for the Development of Intellectual Disability and Autism Spectrum Disorder in Tuberous Sclerosis Complex

Tuberous sclerosis complex (TSC) is a rare multi-system genetic disorder characterized by a high incidence of epilepsy and neuropsychiatric manifestations known as tuberous-sclerosis-associated neuropsychiatric disorders (TANDs), including autism spectrum disorder (ASD) and intellectual disability (ID). MicroRNAs (miRNAs) are small regulatory non-coding RNAs that regulate the expression of more than 60% of all protein-coding genes in humans and have been reported to be dysregulated in several diseases, including TSC. In the current study, RNA sequencing analysis was performed to define the miRNA and isoform (isomiR) expression patterns in serum. A Receiver Operating Characteristic (ROC) curve analysis was used to identify circulating molecular biomarkers, miRNAs, and isomiRs, able to discriminate the development of neuropsychiatric comorbidity, either ASD, ID, or ASD + ID, in patients with TSC. Part of our bioinformatics predictions was verified with RT-qPCR performed on RNA isolated from patients’ serum. Our results support the notion that circulating miRNAs and isomiRs have the potential to aid standard clinical testing in the early risk assessment of ASD and ID development in TSC patients.

Time to Onset of Cannabidiol (CBD) Treatment Effect and Resolution of Adverse Events in Tuberous Sclerosis Complex: Post Hoc Analysis of Randomized Controlled Phase 3 Trial GWPCARE6

Objective

To estimate the timing of cannabidiol (CBD) treatment effect (seizure reduction and adverse events [AEs]) onset, we conducted a post hoc analysis of GWPCARE6 (NCT02544763), a randomized, placebo‐controlled, phase 3 trial in patients with drug‐resistant epilepsy associated with tuberous sclerosis complex (TSC).

Methods

Patients received plant‐derived pharmaceutical formulation of highly purified CBD (Epidiolex; 100 mg/ml oral solution) at 25 mg/kg/day (CBD25) or 50 mg/kg/day (CBD50) or placebo for 16 weeks (4‐week titration, 12‐week maintenance). Treatment started at 5 mg/kg/day for all groups and reached 25 mg/kg/day on Day 9 and 50 mg/kg/day on Day 29. Percentage change from baseline in TSC‐associated seizure (countable focal or generalized) count was calculated by cumulative day (i.e., including all previous days). Time to onset and resolution of AEs were evaluated.

Results

Of 224 patients, 75 were randomized to CBD25, 73 to CBD50, and 76 to placebo. Median (range) age was 11.3 (1.1–56.8) years. Patients had discontinued a median (range) of 4 (0–15) antiseizure medications and were currently taking 3 (0–5). Difference in seizure reduction between CBD and placebo emerged on Day 6 (titrated dose, 15 mg/kg/day) and became nominally significant (p < .049) by Day 10. Separation between placebo and CBD in ≥50% responder rate also emerged by Day 10. Onset of AEs occurred during the first 2 weeks of the titration period in 61% of patients (CBD25, 61%; CBD50, 67%; placebo, 54%). In patients with an AE, resolution occurred within 4 weeks of onset in 42% of placebo and 27% of CBD patients and by end of trial in 78% of placebo and 51% of CBD patients.

Significance

Onset of treatment effect occurred within 6–10 days. AEs lasted longer for CBD than placebo, but the most common (diarrhea, decreased appetite, and somnolence) resolved during the 16‐week trial in most patients.

Patient and Caregiver Health State Utilities in Tuberous Sclerosis Complex

BACKGROUND

Tuberous sclerosis complex (TSC) is a rare multisystem disorder often associated with treatment-resistant epilepsy. Cost-effectiveness analysis for new antiseizure medications typically requires health state utilities (HSUs) that reflect the burden of a given condition.

OBJECTIVE

This study aimed to estimate HSUs, with a focus on valuing the impact of seizure type and seizure frequency on health-related quality of life (HRQL) for patients with TSC and their caregivers.

METHODS

A targeted literature review and qualitative research with healthcare professionals and caregivers informed the development of health state vignettes describing the experience of living with TSC or caring for a child with TSC. Vignettes were evaluated in interviews with the UK general population using the time trade-off (TTO) method.

RESULTS

Sixteen vignettes were developed describing patient HRQL (n = 8) and caregiver HRQL (n = 8). Two hundred interviews were conducted via online video calls due to COVID-19 pandemic restrictions. Two hundred participants evaluated the patient (n = 100) and caregiver (n = 100) health state vignettes. Estimated utility scores varied consistently according to seizure type and seizure frequency. Patient TTO utility scores ranged between -0.234 (highest seizure frequency and multiple seizure types) and 0.725 (seizure-free state). Caregiver TTO utility scores ranged from 0.221 to 0.905.

CONCLUSIONS

Findings highlight the substantial burden of living with TSC and caring for a child with TSC. Patient and caregiver burden was greater for generalised versus focal seizures. The burden was greatest for a combination of both seizure types and worsened with increasing seizure frequency.

Long-term cannabidiol treatment for seizures in patients with tuberous sclerosis complex: An open-label extension trial

Objective

To evaluate the long‐term safety and efficacy of add‐on cannabidiol (CBD) in patients with seizures associated with tuberous sclerosis complex (TSC) in the open‐label extension (OLE) of the randomized, placebo‐controlled phase 3 trial GWPCARE6 (NCT02544763). Results of an interim (February 2019 data cut) analysis are reported.

Methods

Patients who completed the randomized trial enrolled to receive CBD (Epidiolex^® in the United States; Epidyolex^® in the EU; 100 mg/mL oral solution). The initial target dose was 25 mg/kg/day, which, based on response and tolerability, could be decreased or increased up to 50 mg/kg/day. The primary end point was safety. Key secondary end points included percentage reduction in TSC‐associated (countable focal and generalized) seizures, responder rates, and Subject/Caregiver Global Impression of Change (S/CGIC).

Results

Of 201 patients who completed the randomized phase, 199 (99%) entered the OLE. Mean age was 13 years (range, 1–57). At the time of analysis, 5% of patients had completed treatment, 20% had withdrawn, and 75% were ongoing. One‐year retention rate was 79%. Median treatment time was 267 days (range, 18–910) at a 27 mg/kg/day mean modal dose. Most patients (92%) had an adverse event (AE). Most common AEs were diarrhea (42%), seizure (22%), and decreased appetite (20%). AEs led to permanent discontinuation in 6% of patients. There was one death that was deemed treatment unrelated by the investigator. Elevated liver transaminases occurred in 17 patients (9%) patients; 12 were taking valproate. Median percentage reductions in seizure frequency (12‐week windows across 48 weeks) were 54%–68%. Seizure responder rates (≥50%, ≥75%, 100% reduction) were 53%–61%, 29%–45%, and 6%–11% across 12‐week windows for 48 weeks. Improvement on the S/CGIC scale was reported by 87% of patients/caregivers at 26 weeks.

Significance

In patients with TSC, long‐term add‐on CBD treatment was well tolerated and sustainably reduced seizures through 48 weeks, with most patients/caregivers reporting global improvement.

Bilateral renal angiomyolipomas in tuberous sclerosis

Background

Tuberous sclerosis complex (TSC) is a rare genetic disorder characterized by benign hamartomas in multiple organs of the body. Renal angiomyolipomas (AML) are commonly associated with TSC. They are mostly asymptomatic. But large and rapidly growing AMLs with the presence of an aneurysm cause symptoms and pose a life-threatening risk for hemorrhage.

Case presentation

Our patient is a 25-year-old female who presented to us as an undiagnosed case of tuberous sclerosis having a large abdominal mass. She fulfilled the clinical criteria required for the diagnosis of TSC. The CT scan revealed an 18 × 13 × 33 cm fat-containing lesion in the right kidney with an adjacent aneurysm measuring around 16 cm in diameter. Due to the large size of the AML and associated aneurysm, surgical exploration was mandated. On the contralateral kidney, multiple contrast-enhancing soft-tissue densities were present that appeared suspicious on radiology. So a percutaneous biopsy of those lesions was done. Fortunately, it had the same histopathology as an Angiomyolipoma. Nephrectomy of the right-sided kidney with AML has been done. The left-sided lesions that are less than 2 cm and asymptomatic are kept on close surveillance. Any change in size will prompt therapy with mTOR inhibitors.

Conclusion

When dealing with bilateral renal AML, it is important to adopt a conservative approach. When intervention is indicated, the least invasive strategy should be sought and enacted. Radical surgery should be the last resort.

Neuroendocrine pancreatic tumor in a patient with dual diagnosis of tuberous sclerosis complex and basement membrane disease: A case report and review of the literature

Tuberous Sclerosis is a complex genetic disease that has well-defined clinical criteria. These criteria don't include pancreatic neuroendocrine tumors. We represent a rare case of a patient, with a non-functioning pancreatic neuroendocrine tumor and concomitant diagnosis of tuberous sclerosis complex, and basement membrane disease. The patient was diagnosed based on typical radiologic findings. We have suggested close monitoring and during follow-up studies, the disease was stable. Interestingly the patient tested negative for Tuberous Sclerosis Complex (TSC), which suggests that she might be a somatic mosaic and the mutation level in blood lymphocytes was below the detection level. Moreover, a heterozygous pathogenic variant p.(Gly774Arg) and a heterozygous likely pathogenic variant p.(Gly1465Asp) were identified in the COL4A4 gene. COL4A4 gene is responsible for causing autosomal dominant basement membrane disease. In this case report, we discuss clinical, radiologic, and genetic aspects of these diseases, as well as optimal treatment and follow-up strategies. Thus, by presenting this case we would like to increase awareness of pancreatic neuroendocrine tumors in TSC and emphasize the need for follow-up monitoring.

Historical Patterns of Diagnosis, Treatments, and Outcome of Epilepsy Associated With Tuberous Sclerosis Complex: Results From TOSCA Registry

Background: Epilepsy is the most common neurological manifestation in individuals with tuberous sclerosis complex (TSC). However, real-world evidence on diagnosis and treatment patterns is limited. Here, we present data from TuberOus Sclerosis registry to increase disease Awareness (TOSCA) on changes in patterns of epilepsy diagnosis, treatments, and outcomes over time, and detailed epilepsy characteristics from the epilepsy substudy.

Methods: TuberOus Sclerosis registry to increase disease Awareness (TOSCA) was a multicentre, international disease registry, consisting of a main study that collected data on overall diagnostic characteristics and associated clinical features, and six substudies focusing on specific TSC manifestations. The epilepsy substudy investigated detailed epilepsy characteristics and their correlation to genotype and intelligence quotient (IQ).

Results: Epilepsy was reported in 85% of participants, more commonly in younger individuals (67.8% in 1970s to 91.8% in last decade), while rate of treatments was similar across ages (>93% for both infantile spasms and focal seizures, except prior to 1960). Vigabatrin (VGB) was the most commonly used antiepileptic drugs (AEDs). Individuals with infantile spasms showed a higher treatment response over time with lower usage of steroids. Individuals with focal seizures reported similar rates of drug resistance (32.5–43.3%). Use of vagus nerve stimulation (VNS), ketogenic diet, and surgery remained low.

Discussion: The epilepsy substudy included 162 individuals from nine countries. At epilepsy onset, most individuals with infantile spasms (73.2%) and focal seizures (74.5%) received monotherapies. Vigabatrin was first-line treatment in 45% of individuals with infantile spasms. Changes in initial AEDs were commonly reported due to inadequate efficacy. TSC1 mutations were associated with less severe epilepsy phenotypes and more individuals with normal IQ. In individuals with TSC diagnosis before seizure onset, electroencephalogram (EEG) was performed prior to seizures in only 12.5 and 25% of subsequent infantile spasms and focal seizures, respectively.

Conclusions: Our study confirms the high prevalence of epilepsy in TSC individuals and less severe phenotypes with TSC1 mutations. Vigabatrin improved the outcome of infantile spasms and should be used as first-line treatment. There is, however, still a need for improving therapies in focal seizures. Electroencephalogram follow-up prior to seizure-onset should be promoted for all infants with TSC in order to facilitate preventive or early treatment.

Pharmacotherapy for Seizures in Tuberous Sclerosis Complex

Epilepsy is one of the main symptoms affecting the lives of individuals with tuberous sclerosis complex (TSC), causing a high rate of morbidity. Individuals with TSC can present with various types of seizures, epilepsies, and epilepsy syndromes that can coexist or appear in relation to age. Focal epilepsy is the most frequent epilepsy type with two developmental and epileptic encephalopathies: infantile spasms syndrome and Lennox-Gastaut syndrome. Active screening and early management of epilepsy is recommended in individuals with TSC to limit its consequences and its impact on quality of life, cognitive outcome and the economic burden of the disease. The progress in the knowledge of the mechanisms underlying epilepsy in TSC has paved the way for new concepts in the management of epilepsy related to TSC. In addition, we are moving from traditional "reactive" and therapeutic choices with current antiseizure medications used after the onset of seizures, to a proactive approach, aimed at predicting and preventing epileptogenesis and the onset of epilepsy with vigabatrin, and to personalized treatments with mechanistic therapies, namely mechanistic/mammalian target of rapamycin inhibitors. Indeed, epilepsy linked to TSC is one of the only epilepsies for which a predictive and preventive approach can delay seizure onset and improve seizure response. However, the efficacy of such interventions on long-term cognitive and psychiatric outcomes is still under investigation.

Epidemiology, healthcare resource use, and mortality in patients with tuberous sclerosis complex: A population-based study on German health insurance data

PURPOSE

10-year retrospective study to assess burden of illness in individuals with tuberous sclerosis complex (TSC) identified from German healthcare data.

METHODS

Patients with TSC were identified by International Classification of Diseases code Q85.1. Patients with epilepsy were identified by epilepsy diagnosis or antiseizure medication (ASM) prescription after TSC diagnosis.

RESULTS

Using data from 2016 (final study year), 100 patients with TSC were identified (mean [range] age: 38 [1-86] years; male: 40%); prevalence: 7.9 per 100,000 (TSC), 2.2 per 100,000 (TSC with epilepsy). During the 10-year study period (2007-2016), 256 patients with TSC were identified and followed up for 1,784 patient-years (epilepsy: 36%, 616 patient-years). TSC manifestations/comorbidities (apart from epilepsy) were identified more frequently in patients with epilepsy than without. Mean annual healthcare costs for patients with TSC were €6,139 per patient-year (PPY), mostly attributable to medication (35%) and inpatient care (29%). Patients with epilepsy incurred costs more than double those without. Mean (standard deviation [SD]) annual hospitalisation rate (AHR) and length of stay (LOS) PPY: 0.5 (1.0) and 5.9 (18.6) days for TSC. AHR and LOS were greater in patients with epilepsy than without. Mean (SD) number of ASMs prescribed (TSC with epilepsy): 3.0 (2.3) over the entire observable time per patient. Mortality rates (vs. control): 5.08% (vs. 1.69%, p<0.001) for TSC, 7.53% (vs. 0.98%, p<0.001) for TSC with epilepsy, 3.68% (vs. 2.03%, p = 0.003) for TSC without epilepsy.

CONCLUSION

Healthcare costs, resource utilisation, and mortality were greater in patients with TSC and epilepsy than those without epilepsy.

Add-on Cannabidiol Treatment for Drug-Resistant Seizures in Tuberous Sclerosis Complex: A Placebo-Controlled Randomized Clinical Trial

Question

Is add-on cannabidiol superior to placebo in reducing the number of seizures associated with tuberous sclerosis complex?

Findings

In this randomized clinical trial, 224 patients with tuberous sclerosis complex were treated with cannabidiol (25 or 50 mg/kg/day) or matched placebo for 16 weeks. The percentage reduction in the type of seizures regarded as the primary end point was 27% for placebo, 49% for 25 mg/kg/day of cannabidiol, and 48% for 50 mg/kg/day of cannabidiol; a dosage of 25 mg/kg/day led to fewer adverse events than the 50-mg/kg/day dosage.

Meaning

In this study, both cannabidiol dosages were equally efficacious in reducing tuberous sclerosis complex–associated seizures compared with placebo, but the smaller dosage led to fewer adverse events.

Importance

Efficacy of cannabidiol has been demonstrated in seizures associated with Lennox-Gastaut and Dravet syndromes but appears not yet to have been established in conditions with primarily focal seizures, such as tuberous sclerosis complex (TSC).

Objective

To evaluate efficacy and safety of 25-mg/kg/day and 50-mg/kg/day cannabidiol dosages vs placebo against seizures associated with TSC.

Design, Setting, and Participants

This double-blind, placebo-controlled randomized clinical trial (GWPCARE6) enrolled patients between April 6, 2016, and October 4, 2018; follow-up was completed on February 15, 2019. The trial was conducted at 46 sites in Australia, Poland, Spain, the Netherlands, United Kingdom, and United States. Eligible patients (aged 1-65 years) were those with a clinical diagnosis of TSC and medication-resistant epilepsy who had had at least 8 TSC-associated seizures during the 4-week baseline period, with at least 1 seizure occurring in at least 3 of the 4 weeks, and were currently taking at least 1 antiepileptic medication.

Interventions

Patients received oral cannabidiol at 25 mg/kg/day (CBD25) or 50 mg/kg/day (CBD50) or a matched placebo for 16 weeks.

Main Outcomes and Measures

The prespecified primary outcome was the change from baseline in number of TSC-associated seizures for cannabidiol vs placebo during the treatment period.

Results

Of 255 patients screened for eligibility, 31 were excluded and 224 were randomized. Of the 224 included patients (median [range] age, 11.4 [1.1-56.8] years; 93 female patients [41.5%]), 75 were randomized to CBD25, 73 to CBD50, and 76 to placebo, with 201 completing treatment. The percentage reduction from baseline in the type of seizures considered the primary end point was 48.6% (95% CI, 40.4%-55.8%) for the CBD25 group, 47.5% (95% CI, 39.0%-54.8%) for the CBD50 group, and 26.5% (95% CI, 14.9%-36.5%) for the placebo group; the percentage reduction from placebo was 30.1% (95% CI, 13.9%-43.3%; P < .001) for the CBD25 group and 28.5% (95% CI, 11.9%-42.0%; nominal P = .002) for the CBD50 group. The most common adverse events were diarrhea (placebo group, 19 [25%]; CBD25 group, 23 [31%]; CBD50 group, 41 [56%]) and somnolence (placebo group, 7 [9%]; CBD25 group, 10 [13%]; CBD50 group, 19 [26%]), which occurred more frequently with cannabidiol than placebo. Eight patients in CBD25 group, 10 in CBD50 group, and 2 in the placebo group discontinued treatment because of adverse events. Twenty-eight patients taking cannabidiol (18.9%) had elevated liver transaminase levels vs none taking placebo.

Conclusions and Relevance

Cannabidiol significantly reduced TSC-associated seizures compared with placebo. The 25-mg/kg/day dosage had a better safety profile than the 50-mg/kg/day dosage.

Trial Registration

ClinicalTrials.gov Identifier: NCT02544763

A case report of severe tuberous sclerosis complex detected in utero and linked to a novel duplication in the TSC2 gene

BACKGROUND

Disease severity is tremendously variable in tuberous sclerosis complex (TSC). In contrast with the detailed guidelines available for TSC diagnosis and management, clinical practice lacks adequate tools to evaluate the prognosis, especially in the case of in utero diagnosis. In addition, the correlation between genotypes and phenotypes remains a challenge, in part due to the large number of mutations linked to TSC. In this report, we describe a case of severe TSC diagnosed in utero and associated with a specific mutation in the gene tuberous sclerosis complex 2 (TSC2).

CASE PRESENTATION

A mother was referred for a thorough investigation following the observation by ultrasound of cardiac abnormalities in her fetus. The mother was healthy and reported frequent, intense and long-lasting hiccups/spasms in the fetus. The fetus of gestational age 33 weeks and 4 days was found to have multiple cardiac tumors with cardiac ultrasound. Brain magnetic resonance imaging (MRI) performed in utero revealed the presence of sub-ependymal nodules and of abnormal signals disseminated in the white matter, in the cerebral cortex and in the cerebellum. Following diagnosis of definite TSC, pregnancy interruption was chosen by the parents. Genetic testing of the fetus exposed a duplication in exon 41 of TSC2 (c.5169dupA), which was absent in the parents. The autopsy ascertained the high severity of brain damage characterized by an extensive disorganisation of white and grey matter in most cerebral lobes.

CONCLUSIONS

This case presentation is the first to depict the association between a de novo TSC2 c.5169dupA and multi-organ manifestation together with indications of a particularly high disease severity. This report can help physicians to perform early clinical diagnosis of TSC and to evaluate the prognosis.

Epilepsy in Children with Tuberous Sclerosis Complex: A Prospective Observational Study in Bangladesh

Background and Purpose

Epilepsy is an important neurologic feature of patients with tuberous sclerosis complex (TSC). Most common seizure types are focal seizure and epileptic spasm. Seizure control often requires multiple antiepileptic drugs. This study has been done to evaluate the seizure types, electro-encephalography (EEG), neuroimaging features, and drug treatment of epilepsy in TSC.

Methods

This prospective observational study has been conducted on epilepsy patients with TSC at Bangabandhu Sheikh Mujib Medical University from 2011 to 2019.

Results

Seventy patients with a mean±standard deviation age of 5.64±3.96 years were identified and 57.1% were female. Most common type of seizure was focal seizure (46%). Epileptic spasm occurred in 17% of patients and all of them had seizure onset before 1 year. In 47% of patients EEG showed focal epileptic discharge; hypsarrhythmia was found in most of the patients with epileptic spasm. Majority of the patients needed more than one drug to control seizure. Only 34% of patients were seizure free for at least 12 months and 22.8% had drug resistant epilepsy.

Conclusions

This study highlights the pattern of seizure, treatment pattern, response to drug, and short-time outcome of children with TSC with epilepsy in a developing country like Bangladesh.

A systematic review on the burden of illness in individuals with tuberous sclerosis complex (TSC)

Objective

This review will summarize current knowledge on the burden of illness (BOI) in tuberous sclerosis complex (TSC), a multisystem genetic disorder manifesting with hamartomas throughout the body, including mainly the kidneys, brain, skin, eyes, heart, and lungs.

Methods

We performed a systematic analysis of the available literature on BOI in TSC according to the PRISMA guidelines. All studies irrespective of participant age that reported on individual and societal measures of disease burden (e.g. health care resource use, costs, quality of life) were included.

Results

We identified 33 studies reporting BOI in TSC patients. Most studies (21) reported health care resource use, while 14 studies reported quality of life and 10 studies mentioned costs associated with TSC. Only eight research papers reported caregiver BOI. Substantial BOI occurs from most manifestations of the disorder, particularly from pharmacoresistant epilepsy, neuropsychiatric, renal and skin manifestations. While less frequent, pulmonary complications also lead to a high individual BOI. The range for the mean annual direct costs varied widely between 424 and 98,008 International Dollar purchasing power parities (PPP-$). Brain surgery, end-stage renal disease with dialysis, and pulmonary complications all incur particularly high costs. There is a dearth of information regarding indirect costs in TSC. Mortality overall is increased compared to general population; and most TSC related deaths occur as a result of complications from seizures as well as renal complications. Long term studies report mortality between 4.8 and 8.3% for a follow-up of 8 to 17.4 years.

Conclusions

TSC patients and their caregivers have a high burden of illness, and TSC patients incur high costs in health care systems. At the same time, the provision of inadequate treatment that does not adhere to published guidelines is common and centralized TSC care is received by no more than half of individuals who need it, especially adults. Further studies focusing on the cost effectiveness and BOI outcomes of coordinated TSC care as well as of new treatment options such as mTOR inhibitors are necessary.

Epilepsy in tuberous sclerosis complex: Findings from the TOSCA Study

OBJECTIVE

To present the baseline data of the international TuberOus SClerosis registry to increase disease Awareness (TOSCA) with emphasis on the characteristics of epilepsies associated with tuberous sclerosis complex (TSC).

METHODS

Retrospective and prospective patients' data on all aspects of TSC were collected from multiple countries worldwide. Epilepsy variables included seizure type, age at onset, type of treatment, and treatment outcomes and association with genotype, seizures control, and intellectual disability. As for noninterventional registries, the study protocol did not specify any particular clinical instruments, laboratory investigations, or intervention. Evaluations included those required for diagnosis and management following local best practice.

RESULTS

Epilepsy was reported in 83.6% of patients (1852/2216) at baseline; 38.9% presented with infantile spasms and 67.5% with focal seizures. The mean age at diagnosis of infantile spasms was 0.4 year (median <1 year; range <1-30 years) and at diagnosis of focal seizures was 2.7 years (median 1 year; range <1-66 years). A total of 1469 patients (79.3%) were diagnosed with epilepsy <2 years. The rate of infantile spasms was higher in patients with a TSC 2 mutation than in patients with a TSC1 mutation (47.3% vs 23%). ɣ-aminobutyric acid (GABA)ergic drugs were the most common treatment modality for both infantile spasms (78.7%) and focal seizures (65.5%). Infantile spasms and focal seizures were controlled in 76.3% and 58.2% of patients, respectively. Control of seizures was associated with lower rates of intellectual disability in both groups.

SIGNIFICANCE

This registry reports the largest international cohort of patients with TSC. Findings confirmed the typical onset pattern of infantile spasms and other focal seizures in the first 2 years of life, and the high rates of infantile spasms in patients with TSC2 mutation. Our results underscored the occurrence of focal seizures at all ages, including an onset that preceded emergence of infantile spasms. Seizure control was shown to be associated with lower rates of intellectual disability but did not preclude the presence of intellectual disability.

Comorbidities of Rare Epilepsies: Results from the Rare Epilepsy Network

OBJECTIVE

To describe the prevalence and characteristics of comorbidities in persons with rare epilepsies.

STUDY DESIGN

Persons with rare epilepsies and caregivers of those affected were recruited through the Epilepsy Foundation and more than 30 rare epilepsy advocacy organizations affiliated with the Rare Epilepsy Network (REN). A web-based survey was conducted using a questionnaire consisting of core sections to collect data from affected persons on various aspects, including comorbidities. Comorbidity information was grouped into 15 classes, 12 of which had a stem question followed by detailed branch questions and 3 that were created from a combination of related questions.

RESULTS

Of 795 persons with more than 30 different rare epilepsy diagnosis groups, one-half had ≥5 comorbidity classes and 97% were classified as complex chronic disease (C-CD). The highest number of comorbidity classes reported per person were persons with Aicardi syndrome, Phelan-McDermid syndrome (median, 7.0; IQR, 5.0-9.0), and tuberous sclerosis complex (median, 6.0; IQR, 4.0-8.0). The most common comorbidity classes were learning/developmental disability (71%), mental health issues (71%), sleep disorders (60%), brain abnormalities (52%), oral issues (49%), bone-joint issues (42%), hyper/hypotonia (42%), and eye-vision disorders (38%). The prevalence of brain abnormalities, hyper/hypotonia, eye, and cardiac disorders was significantly higher in persons first diagnosed with epilepsy at a younger age (<9 months) than in those first diagnosed at an older age (P < .05 for trend).

CONCLUSIONS

Nearly all persons with rare epilepsies are medically complex, with a high prevalence of multiple comorbidities, especially those who were diagnosed with epilepsy in the first year of life. Comorbidities should be carefully considered in the diagnosis and management of persons with rare epilepsies.

Incidental diagnosis of tuberous sclerosis complex by exome sequencing in three families with subclinical findings

Tuberous sclerosis complex (TSC) is an autosomal-dominant neurocutaneous disorder characterized by lesions and benign tumors in multiple organ systems including the brain, skin, heart, eyes, kidneys, and lungs. The phenotype is highly variable, although penetrance is reportedly complete. We report the molecular diagnosis of TSC in individuals exhibiting extreme intra-familial variability, including the incidental diagnosis of asymptomatic family members. Exome sequencing was performed in three families, with probands referred for epilepsy, autism, and absent speech (Family 1); epileptic spasms (Family 2); and connective tissue disorders (Family 3.) Pathogenic variants in TSC1 or TSC2 were identified in nine individuals, including relatives with limited or no medical concerns at the time of testing. Of the nine individuals reported here, six had post-diagnosis examinations and three met clinical diagnostic criteria for TSC. One did not meet clinical criteria for a possible or definite diagnosis of TSC, and two had only a possible clinical diagnosis following post-diagnosis workup. These individuals as well as their mothers demonstrated limited features that would not raise concern for TSC in the absence of molecular results. In addition, three individuals exhibited epilepsy with normal brain MRIs, and two without seizures or intellectual disability had MRI findings fulfilling major criteria for TSC highlighting the difficulty providers face when relying on clinical criteria to guide genetic testing. Given the importance of a timely TSC diagnosis for clinical management, such cases demonstrate a potential benefit for clinical criteria to include seizures and an unbiased molecular approach to genetic testing.

Predictors of Drug-Resistant Epilepsy in Tuberous Sclerosis Complex

Utilizing the multicenter TSC (tuberous sclerosis complex) Natural History Database including 2034 subjects, this study aimed to identify predictors of drug-resistant epilepsy in TSC. Basic epilepsy data were available for 1965 individuals in the database. Supplemental data were further collected from 1546 of these subjects through directed site queries, addressing additional epilepsy characteristics including the presence of drug-resistant epilepsy, therapies trialed, and outcomes of specific therapies. Epilepsy was reported in 86.4% of individuals with TSC. Infantile spasms were reported in 45.2% of individuals and focal seizures were reported in 84.4% of individuals. In those with focal epilepsy, drug resistance was reported in 59.6%, with focal seizure onset prior to age 1 year (odds ratio [OR] 1.9, confidence interval [CI] 1.4-2.5, P < .001), infantile spasms (OR 2.0, CI 1.5-2.5, P < 0.001), and infantile spasms incompletely responsive to therapy (OR 47.6, CI 6.7-333.3, P < 0.001) being associated with an increased likelihood of drug resistance.

Early Detection of Tuberous Sclerosis Complex: An Opportunity for Improved Neurodevelopmental Outcome

BACKGROUND

Tuberous sclerosis complex (TSC) is an autosomal dominant condition associated with epilepsy, benign tumors, and variable neurodevelopmental outcomes. The diagnosis is most commonly made after epilepsy onset, although a proportion are diagnosed prenatally. Presymptomatic or early treatment with agents such as vigabatrin offers the hope of improved neurodevelopmental outcome. Therefore early diagnosis, before the onset of seizures, is important. In a cohort of children with TSC, we evaluated the age and mode of initial presentation, assessed the neurocognitive and epilepsy outcome, and analyzed whether those diagnosed before the onset of seizures have a different outcome compared with those diagnosed postseizures.

METHODS

We reviewed patients at the TSC clinic at Sydney Children's Hospital who were born between 2001 and 2015.

RESULTS

A total of 74 patients were identified: 34 (46%) diagnosed preseizure (21 prenatally) and 40 (54%) postseizure. In the preseizure cohort, 77% presented with cardiac rhabdomyoma(s) and 72% developed seizures. The postseizure cohort had more severe epilepsy, requiring more antiepileptic drugs for seizure control (median five, compared with three in the preseizure cohort [P = 0.01]). Developmental disability occurred in 65% of the preseizure cohort compared with 72% of the postseizure cohort. Severe developmental disability most often occurred in children who had their first seizure before age 12 months.

CONCLUSION

Children who are diagnosed with TSC before the onset of seizures have less severe epilepsy and better developmental outcome.