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Brain : a Journal of Neurology Jul 2023Epileptogenesis in infants with tuberous sclerosis complex (TSC) is a gradual and dynamic process, leading to early onset and difficult-to-treat seizures. Several... (Review)
Review
Epileptogenesis in infants with tuberous sclerosis complex (TSC) is a gradual and dynamic process, leading to early onset and difficult-to-treat seizures. Several cellular, molecular and pathophysiologic mechanisms, including mammalian target of rapamycin (mTOR) dysregulation, GABAergic dysfunction and abnormal connectivity, may play a role in this epileptogenic process and may also contribute to the associated developmental encephalopathy. Disease-specific antiseizure medications or drugs targeting the mTOR pathway have proved to be effective in TSC-associated epilepsy. Pre-symptomatic administration of vigabatrin, a GABAergic drug, delays seizure onset and reduces the risk of a subsequent epileptic encephalopathy, such as infantile spasms syndrome or Lennox-Gastaut syndrome. Everolimus, a rapamycin-derived mTOR inhibitor, reduces seizure frequency, especially in younger patients. This evidence suggests that everolimus should be considered early in the course of epilepsy. Future trials are needed to optimize the use of everolimus and determine whether earlier correction of mTOR dysregulation can prevent progression to developmental and epileptic encephalopathies or mitigate their severity in infants with TSC. Clinical trials of several other potential antiseizure drugs (cannabidiol and ganaxolone) that target contributing mechanisms are also underway. This review provides an overview of the different biological mechanisms occurring in parallel and interacting throughout the life course, even beyond the epileptogenic process, in individuals with TSC. These complexities highlight the challenges faced in preventing and treating TSC-related developmental and epileptic encephalopathy.
Topics: Infant; Humans; Everolimus; Tuberous Sclerosis; Epilepsy; Seizures; Sirolimus; TOR Serine-Threonine Kinases; Anticonvulsants
PubMed: 36806388
DOI: 10.1093/brain/awad048 -
Neuro-oncology Oct 2023Selumetinib shrank inoperable symptomatic plexiform neurofibromas (PN) in children with neurofibromatosis type 1 (NF1) and provided clinical benefit for many in our...
BACKGROUND
Selumetinib shrank inoperable symptomatic plexiform neurofibromas (PN) in children with neurofibromatosis type 1 (NF1) and provided clinical benefit for many in our previously published phase 1/2 clinical trials (SPRINT, NCT01362803). At the data cutoff (DCO) of the prior publications, 65% of participants were still receiving treatment. This report presents up to 5 years of additional safety and efficacy data from these studies.
METHODS
This manuscript includes data from the phase 1 and phase 2, stratum 1 study which included participants with clinically significant PN-related morbidity. Participants received continuous selumetinib dosing (1 cycle = 28 days). Safety and efficacy data through February 27, 2021 are included. PN response assessed by volumetric magnetic resonance imaging analysis: Confirmed partial response (cPR) ≥20% decrease from baseline on 2 consecutive evaluations. Phase 2 participants completed patient-reported outcome measures assessing tumor pain intensity (Numeric Rating Scale-11) and interference of pain in daily life (pain interference index).
RESULTS
For the 74 children (median age 10.3 years; range 3-18.5) enrolled, overall cPR rate was 70% (52/74); median duration of treatment was 57.5 cycles (range 1-100). Responses were generally sustained with 59% (44) lasting ≥ 12 cycles. Tumor pain intensity (n = 19, P = .015) and pain interference (n = 18, P = .0059) showed durable improvement from baseline to 48 cycles. No new safety signals were identified; however, some developed known selumetinib-related adverse events (AEs) for the first time after several years of treatment.
CONCLUSIONS
With up to 5 years of additional selumetinib treatment, most children with NF1-related PN had durable tumor shrinkage and sustained improvement in pain beyond that previously reported at 1 year. No new safety signals were identified; however, ongoing monitoring for known selumetinib-related AEs is needed while treatment continues.
Topics: Child; Humans; Neurofibromatosis 1; Neurofibroma, Plexiform; Benzimidazoles; Pain
PubMed: 37115514
DOI: 10.1093/neuonc/noad086 -
The Journal of Clinical Investigation Apr 2024Capillary malformation (CM), or port wine birthmark, is a cutaneous congenital vascular anomaly that occurs in 0.1%-2% of newborns. Patients with a CM localized on the... (Review)
Review
Capillary malformation (CM), or port wine birthmark, is a cutaneous congenital vascular anomaly that occurs in 0.1%-2% of newborns. Patients with a CM localized on the forehead have an increased risk of developing a neurocutaneous disorder called encephalotrigeminal angiomatosis or Sturge-Weber syndrome (SWS), with complications including seizure, developmental delay, glaucoma, and vision loss. In 2013, a groundbreaking study revealed causative activating somatic mutations in the gene (GNAQ) encoding guanine nucleotide-binding protein Q subunit α (Gαq) in CM and SWS patient tissues. In this Review, we discuss the disease phenotype, the causative GNAQ mutations, and their cellular origin. We also present the endothelial Gαq-related signaling pathways, the current animal models to study CM and its complications, and future options for therapeutic treatment. Further work remains to fully elucidate the cellular and molecular mechanisms underlying the formation and maintenance of the abnormal vessels.
Topics: Infant, Newborn; Animals; Humans; Glaucoma; Models, Animal; Mutation; Capillaries; Vascular Malformations
PubMed: 38618955
DOI: 10.1172/JCI172842 -
European Journal of Paediatric... Nov 2023Children with tuberous sclerosis complex (TSC), may experience a variety of seizure types in the first year of life, most often focal seizure sand epileptic spasms. Drug... (Review)
Review
Children with tuberous sclerosis complex (TSC), may experience a variety of seizure types in the first year of life, most often focal seizure sand epileptic spasms. Drug resistance is seen early in many patients, and the management of TSC associated epilepsy remain a major challenge for clinicians. In 2018 clinical recommendations for the management of TSC associated epilepsy were published by a panel of European experts. In the last five years considerable progress has been made in understanding the neurobiology of epileptogenesis and three interventional randomized controlled trials have changed the therapeutic approach for the management of TSC associated epilepsy. Pre-symptomatic treatment with vigabatrin may delay seizure onset, may reduce seizure severity and reduce the risk of epileptic encephalopathy. The efficacy of mTOR inhibition with adjunctive everolimus was documented in patients with TSC associated refractory seizures and cannabidiol could be another therapeutic option. Epilepsy surgery has significantly improved seizure outcome in selected patients and should be considered early in all patients with drug resistant epilepsy. There is a need to identify patients who may have a higher risk of developing epilepsy and autism spectrum disorder (ASD). In the recent years significant progress has been made owing to the early identification of risk factors for the development of drug-resistant epilepsy. Better understanding of the mechanism underlying epileptogenesis may improve the management for TSC-related epilepsy. Developmental neurobiology and neuropathology give opportunities for the implementation of concepts related to clinical findings, and an early genetic diagnosis and use of EEG and MRI biomarkers may improve the development of pre-symptomatic and disease-modifying strategies.
Topics: Child; Humans; Tuberous Sclerosis; Autism Spectrum Disorder; Epilepsy; Seizures; Drug Resistant Epilepsy
PubMed: 37669572
DOI: 10.1016/j.ejpn.2023.08.005