Everolimus dosing recommendations for tuberous sclerosis complex-associated refractory seizures.

OBJECTIVE: The present analysis examined the exposure-response relationship by means of the predose everolimus concentration (Cmin ) and the seizure response in patients with tuberous sclerosis complex-associated seizures in the EXIST-3 study. Recommendations have been made for the target Cmin range of everolimus for therapeutic drug monitoring (TDM) and the doses necessary to achieve this target Cmin . METHODS: A model-based approach was used to predict patients' daily Cmin . Time-normalized Cmin (TN-Cmin ) was calculated as the average predicted Cmin in a time interval. TN-Cmin was used to link exposure to efficacy and safety end points via model-based approaches. A conditional logistic regression stratified by age subgroup was used to estimate the probability of response in relation to exposure. A multiplicative linear regression model was used to estimate the exposure-response relationship for seizure frequency (SF). An extended Cox regression model was used to link exposure to the time to first adverse event. RESULTS: There was a strong, consistent, and highly significant relationship between everolimus exposure and efficacy, measured by TN-Cmin and SF, regardless of patient's age and concomitant use of cytochrome P450 3A4 (CYP3A4) inhibitors/inducers. Results of an extended Cox regression analyses indicated that twofold increases in TN-Cmin were not associated with statistically significant increases in the risk of stomatitis or infections. SIGNIFICANCE: The recommended TDM is to target everolimus Cmin within a range of 5-7 ng/mL initially and 5-15 ng/mL in the event of an inadequate clinical response, and safety is consistent with previous reports. Starting doses depend on age and the concomitant use of CYP3A4/P-glycoprotein inducers/inhibitors.

In situ repair of vagus nerve stimulator lead damage: technical note.

Vagus nerve stimulators (VNSs) are currently an accepted treatment for intractable epilepsy not amenable to ablative surgery. Battery death and lead damage are the main reasons for reoperation in patients with VNSs. In general, any damage to the lead requires revision surgery to remove the helical electrodes from the vagus nerve and replace the electrode array and wire. The electrodes are typically scarred and difficult to remove from the vagus nerve without injury. The authors describe 6 patients with VNSs who presented with low lead impedance on diagnostic testing, leading to the intraoperative finding of lead insulation disruption, or who were found incidentally at the time of implantable pulse generator battery replacement to have a tear in the outer insulation of the electrode wire. Instead of replacement, the wire insulation was repaired and reinforced in situ, leading to normal impedance testing. All 6 devices remained functional over a follow-up period of up to 87 months, with 2 of the 6 patients having a relatively shorter follow-up of only 12 months. This technique, applicable in a subset of patients with VNSs requiring lead exploration, obviates the need for lead replacement with its attendant risks.

Long-Term Use of Everolimus in Patients with Tuberous Sclerosis Complex: Final Results from the EXIST-1 Study.

BACKGROUND: Everolimus, a mammalian target of rapamycin (mTOR) inhibitor, has demonstrated efficacy in treating subependymal giant cell astrocytomas (SEGAs) and other manifestations of tuberous sclerosis complex (TSC). However, long-term use of mTOR inhibitors might be necessary. This analysis explored long-term efficacy and safety of everolimus from the conclusion of the EXIST-1 study (NCT00789828). METHODS AND FINDINGS: EXIST-1 was an international, prospective, double-blind, placebo-controlled phase 3 trial examining everolimus in patients with new or growing TSC-related SEGA. After a double-blind core phase, all remaining patients could receive everolimus in a long-term, open-label extension. Everolimus was initiated at a dose (4.5 mg/m2/day) titrated to a target blood trough of 5-15 ng/mL. SEGA response rate (primary end point) was defined as the proportion of patients achieving confirmed ≥50% reduction in the sum volume of target SEGA lesions from baseline in the absence of worsening nontarget SEGA lesions, new target SEGA lesions, and new or worsening hydrocephalus. Of 111 patients (median age, 9.5 years) who received ≥1 dose of everolimus (median duration, 47.1 months), 57.7% (95% confidence interval [CI], 47.9-67.0) achieved SEGA response. Of 41 patients with target renal angiomyolipomas at baseline, 30 (73.2%) achieved renal angiomyolipoma response. In 105 patients with ≥1 skin lesion at baseline, skin lesion response rate was 58.1%. Incidence of adverse events (AEs) was comparable with that of previous reports, and occurrence of emergent AEs generally decreased over time. The most common AEs (≥30% incidence) suspected to be treatment-related were stomatitis (43.2%) and mouth ulceration (32.4%). CONCLUSIONS: Everolimus use led to sustained reduction in tumor volume, and new responses were observed for SEGA and renal angiomyolipoma from the blinded core phase of the study. These findings support the hypothesis that everolimus can safely reverse multisystem manifestations of TSC in a significant proportion of patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT00789828.

Everolimus for subependymal giant cell astrocytoma in patients with tuberous sclerosis complex: 2-year open-label extension of the randomised EXIST-1 study.

BACKGROUND: In the EXIST-1 trial, initiated on Aug 10, 2009, more than 35% of patients with subependymal giant cell astrocytoma (SEGA) associated with tuberous sclerosis complex had at least 50% reduction in SEGA volume after 9·6 months of treatment with everolimus. In this Article, we report interim data (up to Jan 11, 2013) to support longer-term tolerability and efficacy of everolimus from the continuing 4-year extension phase of EXIST-1. METHODS: We assessed data from a prospective, open-label extension of a multicentre, phase 3, randomised, double-blind, placebo-controlled study in patients with tuberous sclerosis complex who had SEGA that was growing and needed treatment. In this extension study, we included all patients who had been assigned everolimus during the double-blind, randomised phase of the trial and those patients who crossed over from the placebo group to receive everolimus during the randomised phase or at the start of the extension phase. All patients received oral everolimus at a starting dose of 4·5 mg/m(2) per day. Everolimus dose was subsequently adjusted subject to tolerability to attain blood trough concentrations of 5-15 ng/mL. An independent central radiology review team assessed SEGA response (at least a 50% reduction from baseline in total volume of all target SEGAs; the primary endpoint) by MRI at 12, 24, and 48 weeks, then every year thereafter in all patients who received at least one dose of everolimus. This study was registered with ClinicalTrials.gov, number NCT00789828. FINDINGS: Of the original 117 randomly assigned patients, 111 were given everolimus between Aug 20, 2009, and Jan 11, 2013 (date of data cutoff); we included these patients in our longer-term analysis. Median duration of everolimus exposure was 29·3 months (IQR 19·4-33·8). Median follow-up was 28·3 months (IQR 19·3-33·0). 54 (49%) patients had a response of 50% or greater reduction in SEGA volume (95% CI 39·0-58·3), and duration of response was between 2·1 and 31·1 months (median not reached). SEGA volume was reduced by 50% or more in 39 (37%) of 105 patients at 24 weeks, 48 (46%) of 104 patients at 48 weeks, 36 (47%) of 76 patients at 96 weeks, and 11 (38%) of 29 patients at 144 weeks. Stomatitis (48 [43%] patients) and mouth ulceration (33 [30%] patients) were the most frequent treatment-related adverse events; infections were the most commonly reported treatment-related serious adverse event, occurring in 15 (14%) patients. 35 (32%) patients reported treatment-related grade 3 or 4 adverse events, the most common of which were stomatitis (nine [8%]) and pneumonia (nine [8%]). 18 (16%) patients had treatment-related serious adverse events. Six (5%) patients withdrew because of adverse events. INTERPRETATION: These results support the longer-term use of everolimus in patients who have few treatment options and who need continued treatment for tuberous sclerosis complex and its varied manifestations. Reduction or stabilisation of tumour volume with everolimus will hopefully provide long-term clinical benefit in patients with SEGA. FUNDING: Novartis Pharmaceuticals.

The effect of everolimus on renal angiomyolipoma in patients with tuberous sclerosis complex being treated for subependymal giant cell astrocytoma: subgroup results from the randomized, placebo-controlled, Phase 3 trial EXIST-1.

BACKGROUND: Tuberous sclerosis complex (TSC) is characterized by benign tumours in multiple organs, including the brain, kidneys, skin, lungs and heart. Our objective was to evaluate everolimus, an mTOR inhibitor, in the treatment of angiomyolipoma in patients with subependymal giant cell astrocytoma (SEGA) associated with TSC. METHODS: EXamining everolimus In a Study of Tuberous Sclerosis Complex-1 (NCT00789828), a prospective, double-blind, randomized, placebo-controlled, Phase 3 study, examined everolimus in treating SEGA associated with TSC. Patients with serial SEGA growth from pre-baseline to baseline scans were randomly assigned (2:1) to receive 4.5 mg/m(2)/day everolimus (target blood trough: 5-15 ng/mL; n = 78) or placebo (n = 39). Angiomyolipoma response rates were analysed in patients (n = 44) with target baseline angiomyolipoma lesions (≥1 angiomyolipoma; longest diameter ≥1.0 cm). An angiomyolipoma response rate, defined as the proportion of patients with confirmed angiomyolipoma response, was assessed by kidney CT or MRI screening at baseline, at 12, 24 and 48 weeks and annually. RESULTS: Angiomyolipoma response rates were 53.3% (16/30) and 0% (0/14) for everolimus- and placebo-treated patients, respectively. Angiomyolipoma reductions ≥50% in the sum of volumes of all target lesions were seen only in everolimus-treated patients (56.5, 78.3 and 80.0%) compared with placebo-treated patients (0% at each time point) at Weeks 12, 24 and 48, respectively. Greater percentages of everolimus-treated patients had angiomyolipoma reductions ≥30% at these same time points (82.6, 100 and 100% versus 8.3, 18.2 and 16.7% for everolimus versus placebo, respectively). CONCLUSIONS: Everolimus showed efficacy in reducing angiomyolipoma lesion volume in patients with SEGA associated with TSC.The trial is registered with ClinicalTrials.gov, number NCT00789828; http://clinicaltrials.gov/ct2/show/NCT00789828?term=EXIST-1&rank=1.

Efficacy and safety of everolimus for subependymal giant cell astrocytomas associated with tuberous sclerosis complex (EXIST-1): a multicentre, randomised, placebo-controlled phase 3 trial.

BACKGROUND: Tuberous sclerosis complex is a genetic disorder leading to constitutive activation of mammalian target of rapamycin (mTOR) and growth of benign tumours in several organs. In the brain, growth of subependymal giant cell astrocytomas can cause life-threatening symptoms--eg, hydrocephalus, requiring surgery. In an open-label, phase 1/2 study, the mTOR inhibitor everolimus substantially and significantly reduced the volume of subependymal giant cell astrocytomas. We assessed the efficacy and safety of everolimus in patients with subependymal giant cell astrocytomas associated with tuberous sclerosis complex. METHODS: In this double-blind, placebo-controlled, phase 3 trial, patients (aged 0-65 years) in 24 centres in Australia, Belgium, Canada, Germany, the UK, Italy, the Netherlands, Poland, Russian Federation, and the USA were randomly assigned, with an interactive internet-response system, in a 2:1 ratio to oral everolimus 4·5 mg/m(2) per day (titrated to achieve blood trough concentrations of 5-15 ng/mL) or placebo. Eligible patients had a definite diagnosis of tuberous sclerosis complex and at least one lesion with a diameter of 1 cm or greater, and either serial growth of a subependymal giant cell astrocytoma, a new lesion of 1 cm or greater, or new or worsening hydrocephalus. The primary endpoint was the proportion of patients with confirmed response--ie, reduction in target volume of 50% or greater relative to baseline in subependymal giant cell astrocytomas. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00789828. FINDINGS: 117 patients were randomly assigned to everolimus (n=78) or placebo (n=39). 27 (35%) patients in the everolimus group had at least 50% reduction in the volume of subependymal giant cell astrocytomas versus none in the placebo group (difference 35%, 95% CI 15-52; one-sided exact Cochran-Mantel-Haenszel test, p<0·0001). Adverse events were mostly grade 1 or 2; no patients discontinued treatment because of adverse events. The most common adverse events were mouth ulceration (25 [32%] in the everolimus group vs two [5%] in the placebo group), stomatitis (24 [31%] vs eight [21%]), convulsion (18 [23%] vs ten [26%]), and pyrexia (17 [22%] vs six [15%]). INTERPRETATION: These results support the use of everolimus for subependymal giant cell astrocytomas associated with tuberous sclerosis. Additionally, everolimus might represent a disease-modifying treatment for other aspects of tuberous sclerosis. FUNDING: Novartis Pharmaceuticals.

A retrospective study comparing preoperative evaluations and postoperative outcomes in paediatric and adult patients undergoing surgical resection for refractory epilepsy.

PURPOSE: To review and compare the preoperative characteristics and postsurgical outcomes in paediatric and adult patients who underwent surgical resections from 2001 to 2009. METHODS: Combined data from noninvasive measures such as ictal semiology, interictal/ictal scalp EEGs, MRI and SPECT were utilised to identify the epileptogenic zones (EZ). When noninvasive investigations produced inconclusive or inconsistent findings, patients underwent intracranial EEG monitoring. Resective micro-surgical procedures were conducted according to the results of the anatomo-electro-clinical investigations and were carried out to remove the EZ. We then followed up 222 paediatric (≤18 years old) and 100 adult patients (≥19 years old) for 1-9 years postoperatively. RESULTS: The mean age of seizure onset in paediatric group was significantly lower than that in adult group. 95 (43%) of the paediatric and 42 (42%) of the adult patients required long-term intracranial EEG recording. 54 (24.3%) of the paediatric and 62 (62%) of the adult patients were found to have temporal lobe epilepsy (TLE), while 149 (67.1%) of the paediatric and 37 (37.0%) of the adult patients had extra-temporal lobe epilepsy (ETLE) (p=0.000). 19 (8.6%) of the paediatric patients and 1 (1%) adult patient had hemispheric lesions (p=0.009). 148 (66.7%) of the paediatric and 61 (61.0%) of the adult patients were seizure-free during the follow-up period. 17 of 19 (89.5%) children who underwent hemispherectomy were seizure-free. In both paediatric and adult groups, the surgical outcome for patients with TLE was significantly better than that of patients with ETLE (p=0.018 in children, p=0.029 in adults). Both the location of EZs and seizure-free ratio were significantly different (p<0.001) between the preadolescent (≤12 years old) and adolescent (13-18 years old) group. Hippocampal sclerosis was the most common pathologic finding in patients with TLE in both groups, and was followed by focal cortical dysplasia. In patients with TLE, the proportion of tumour was significantly higher in the paediatric than the adult group (25.9% vs. 10%, p=0.021). CONCLUSION: Paediatric patients with refractory seizures had more extratemporal or hemispheric resectable epileptogenic foci and fewer temporal foci than adults. Our study demonstrates that resective surgery is an effective and safe early intervention in strictly selected paediatric patients with refractory epilepsy.

Emerging treatments in the management of tuberous sclerosis complex.

Tuberous sclerosis complex is a genetic disorder characterized by the formation of nonmalignant hamartomas in the brain, heart, skin, kidney, lung, and other organs. It is associated with autism, epilepsy, and other neurocognitive and behavioral disabilities. Wide phenotypic variation occurs in disease severity and natural course: some patients demonstrate minimal effects, e.g., skin changes; others manifest profound seizures and mental retardation. Tuberous sclerosis complex is caused by mutations in either the tuberous sclerosis complex 1 or 2 gene (coding for hamartin and tuberin, respectively). The tuberous sclerosis complex 1/tuberous sclerosis complex 2 protein dimer complex is a crucial inhibitory element in the mammalian target of rapamycin pathway, regulating cell growth and proliferation. Until recently, few options existed, other than surgery, for treating symptoms of tuberous sclerosis complex related to the growth of hamartomas. Increased understanding of the genetic cause of the disease and underlying dysregulation of the mammalian target of rapamycin pathway has led to clinical trials of mammalian target of rapamycin inhibitors, including sirolimus and everolimus. This review gives an overview of tuberous sclerosis complex and its molecular causes, and summarizes results from recent clinical trials of mammalian target of rapamycin inhibitors in patients with the disease.

Neuronal bursting properties in focal and parafocal regions in pediatric neocortical epilepsy stratified by histology.

To test the hypothesis that focal and parafocal neocortical tissue from pediatric patients with intractable epilepsy exhibits cellular and synaptic differences, the authors characterized the propensity of these neurons to generate (a) voltage-dependent bursting and (b) synaptically driven paroxysmal depolarization shifts. Neocortical slices were prepared from tissue resected from patients with intractable epilepsy. Multiunit network activity and simultaneous whole-cell patch recordings were made from neurons from three patient groups: (1) those with normal histology; (2) those with mild and severe cortical dysplasia; and (3) those with abnormal pathology but without cortical dysplasia. Seizure-like activity was characterized by population bursting with concomitant bursting in intracellularly recorded cortical neurons (n = 59). The authors found significantly more N-methyl-D-aspartic acid-driven voltage-dependent bursting neurons in focal versus parafocal tissue in patients with severe cortical dysplasia (P < 0.01). Occurrence of paroxysmal depolarization shifts and burst amplitude and burst duration were significantly related to tissue type: focal or parafocal (P < 0.05). The authors show that functional differences between focal and parafocal tissue in patients with severe cortical dysplasia exist. There are functional differences between patient groups with different histology, and bursting properties can be significantly associated with the distinction between focal and parafocal tissue.