Cinromide in Epilepsy: A Pilot Study

Monotherapy with the experimental antiepileptic drug cinromide was evaluated in 11 adult outpatients with uncontrolled partial epilepsy. They were treated with phenytoin for 2 months, cinromide for 4 months, and carbamazepine for 4 months. Four patients withdrew from the study during or shortly after crossover to cinromide due to increased seizure frequency or severity. Of the remainder, three preferred carbamazepine, two cinromide, and two phenytoin, based on both seizure control and degree of toxicity. Overall seizure control was not significantly different with any of the three agents, but during cinromide administration secondarily generalized seizure control was uniformly worst and there was also a tendency toward decreased performance on neuropsychological tests. CNS toxicity and gastrointestinal toxicity were prominent during the first month of cinromide treatment, but subsided with time or dose reduction. No abnormalities requiring drug withdrawal were found with laboratory testing. The results suggested, at best, a very limited clinical usefulness for cinromide, and it has been withdrawn from testing by its manufacturer.     

Pharmacokinetic and Dose Tolerability Study of ADD 94057 in Comedicated Patients with Partial Seizures

ADD 94057, a metabolite of fluzinamide, manufactured by the A. H. Robins Company, blocks chemically- and electrically-induced seizures in animals. The primary objective of this open add-on study was to evaluate patient tolerability of ADD 94057 at ascending target plasma concentrations. Nine subjects with medically refractory seizures were receiving phenytoin (PHT, 3), carbamazepine (CBZ, 3), or both (3). A pharmacokinetic profile after a single oral 400-mg dose of ADD 94057 was used to calculate ADD 94057 dosages. After a 4-week baseline period, patients were treated for 4 weeks with weekly ADD 94057 dosage escalations. Two patients completed the study at their assigned highest dosage level; the other patients finished the study at lower dosages. The patients receiving PHT (but not CBZ) tolerated higher plasma concentrations of ADD 94057 than did patients receiving CBZ, alone or in combination with PHT. Adverse experiences included headache, ataxia, blurred vision, diplopia, dizziness, lightheadedness, and mild confusion. Eight of nine patients had reductions in seizure frequency from baseline.     

Prognosis of Partial Epileptic Seizures in the Adolescent

Actuarial analysis was applied to the notes of 235 patients having a partial seizure for the first time between the ages of 12 and 18 years to establish the best predictive indicators of outcome. Among the factors considered to affect significantly the outcome were the seizure type (elementary or complex symptomatology), the initial EEG, the seizure frequency, the etiological factors, and an association with generalized seizures. Sex, age of onset, and topography of EEG paroxysmal abnormalities had no significance. An algorithm allows the prediction of the prognosis of these seizures at two different times immediately after a first seizure in some cases and after a 1-year survey in others.     

Efficacy of Topiramate as Adjunctive Therapy in Refractory Partial Seizures: United States Trial Experience

Summary: In companion double-blind, placebo-controlled, dose-ranging trials performed in the United States, topiramate (TPM) daily target dosages of 200-1,000 mg/day were evaluated as add-on therapy in adults with refractory partial seizures with or without becoming secondarily generalized. Net reductions in median monthly seizure frequency (active drug minus placebo) with the most efficacious dosages of TPM were 35% in the low-dose trial and 40% in the high-dose trial. Substantial reductions in secondarily generalized seizures were also observed with TPM. TPM appears to be an efficacious new antiepileptic drug in the management of partial epilepsy.     

Placebo-Controlled Pilot Study of Centromedian Thalamic Stimulation in Treatment of Intractable Seizures

Stimulation of centromedian (CM) thalamic nuclei has been proposed as a treatment for seizures. We implanted programmable subcutaneous (s.c.) stimulators into CM bilaterally in 7 patients with intractable epilepsy to test feasibility and safety. Stimulation was on or off in 3-month blocks, with a 3-month washout period in a double-blind, cross-over protocol. Stimuli were delivered as 90-microseconds pulses at 65 pulses/s, 1 min of each 5 min for 2 h/day, with voltage set to half the sensory threshold. Stimulation was safe and well-tolerated, with a mean reduction of tonic-clonic seizure frequency of 30% with respect to baseline when stimulator was on versus a decrease of 8% when the stimulator was off. There was no improvement in total number of generalized seizures with stimulation, and treatment differences were not statistically significant. Stimulation at low intensity did not alter the EEG acutely, but high-intensity stimulation induced slow waves or 2-3 Hz spike-waves with ipsilateral frontal maximum. In an open-label follow-up segment with stimulator trains continuing for 24 h/day, 3 of 6 patients reported at least a 50% decrease in seizure frequency. There were no side effects. This pilot project demonstrated the feasibility of controlled study of thalamic stimulation in epilepsy, but further study will be needed to demonstrate efficacy.     

Efficacy and Tolerability of Vigabatrin in Children with Refractory Partial Seizures: A Single-Blind Dose-Increasing Study

Summary: The efficacy and tolerability of vigabatrin (VGB) in children with refractory partial epilepsy were assessed in a single-blind, add-on, fixed-sequence, placebo-controlled trial. After 1-month observation, the patients entered a 7-month treatment period that involved administration of placebo for 1 month followed by VGB at the initial dosage of 40 mg/kg/day, to be increased to 60 and 80 mg/kg/day at 2-month intervals if seizures persisted. Of the 46 children enrolled in the study, 7 dropped out prematurely due to lack of efficacy of the drug (n = 6) or increased seizure frequency (n = 1). In 11 patients who either became seizure-free (n = 3) or improved markedly (n = 8), treatment was completed at a dose <80 mg/kg/day. The average number of seizures per month in the 39 patients who completed the study decreased from 97 during placebo to 21,12, and 9 after 2, 4, and 6 months of VGB treatments respectively (p < 0.0001 at each time). Response to VGB remained statistically significant when dropouts were included in the evaluation. The number of patients who had <50% reduction in seizure frequency after 2, 4, and 6 months was 28, 33, and 35, respectively. Eight patients became seizure-free during the last 2 months of VGB treatment (3 at 40, 3 at 60, and 2 at 80 mg/kg/day, as compared with none during placebo treatment). Serum levels of associated antiepileptic drugs (AEDs) showed no signscant changes, except for serum phenytoin (PHT) concentration, which significantly (p < 0.01) decreased after VGB treatment. Increased appetite and sedation were observed in 17 and 11% of cases, respectively. VGB is effective in the management of refractory partial epilepsy in children, and in some patients a positive dose-response relationship appears to occur over the assessed dosing range.     

Zonisamide in Epilepsy: A Pilot Study

We compared zonisamide monotherapy (12 weeks) to carbamazepine monotherapy (12 weeks) after phenytoin baseline monotherapy (8 weeks) in an open crossover pilot study of eight adults with uncontrolled partial seizures. Zonisamide had definite antiepileptic activity in five subjects. In two of these, response to zonisamide was superior to that to either phenytoin or carbamazepine. A third subject became seizure free on zonisamide, but had to be withdrawn after 18 days because of mild Stevens-Johnson syndrome. The other three subjects were withdrawn from the study because of drug toxicity, manifested mainly by impaired higher mental function and increased seizures. The best response to zonisamide was at doses approximating 6 mg/kg/day, with plasma levels of 20-30 mg/L. Plasma levels of greater than 30 mg/L usually were associated with toxicity. The pharmacokinetics of zonisamide are complex and nonlinear, with steady-state plasma levels being approximately three times higher than those predicted from a single-dose study.     

Intractable Complex Partial Seizures Associated with Posterior Cerebral Artery Giant Aneurysm: A Case Report

Summary: Giant aneurysms have rarely been reported in association with intractable complex partial seizures (CPS). We report a 30-year-old man with intractable CPS since age 18 years. Seizure onset was electrically localized to right temporal lobe. Preoperative neuroimaging studies showed a partially thrombosed giant aneurysm of the right posterior cerebral artery. Selective arnygdalo- hippocampectomy and occlusion of the posterior cerebral artery did not cause deficits. The patient has been seizure-free for 15 months after operation. We review the relevant literature on aneurysms as a cause of epilepsy.     

Gabapentin as Add-On Therapy in Children with Refractory Partial Seizures: A 12-Week, Multicentre, Double-Blind, Placebo-Controlled Study

PURPOSE: To evaluate the efficacy and safety of gabapentin (Neurontin; GBP) as add-on therapy for refractory partial seizures in paediatric patients aged 3-12 years. METHODS: After a 6-week baseline period, 247 patients (54 centres) entered a 12-week double-blind phase and were randomized to receive either GBP (t.i.d., titrated to 23-35 mg/kg/ day) or placebo. Seizure activity and type were recorded daily. Efficacy variables included Response Ratio (RRatio), responder rate, and percentage change in frequency (PCH) for all partial seizures; PCH and RRatio for individual types of partial seizures; and investigator and parent/guardian global assessments of seizure frequency and patient well-being. RESULTS: RRatio for all partial seizures was significantly lower (better) for GBP-treated patients (p = 0.0407). Responder rate favored GBP, but the difference between treatment groups was not statistically significant. Median PCH for all partial seizures for the GBP treatment group (-17.0%) was better than that for the placebo group (-6.5%). Median PCH for specific seizure types showed GBP to be most effective in controlling complex partial seizures (-35%) and secondarily generalized seizures (-28%) when compared with placebo (-12%, +13%, respectively). A greater percentage of GBP-treated patients exhibited improvement according to investigator and parent/guardian global assessments, with a statistically significant difference observed in the parent/guardian global assessment of seizure-frequency reduction (p = 0.046). Three GBP patients and one placebo patient were seizure free during the double-blind treatment period. GBP was well tolerated. CONCLUSIONS: GBP was effective and well tolerated as an add-on therapy for partial seizures in paediatric patients with previously drug-resistant seizures.     

Hypnic Tonic Postural Seizures in Healthy Children Provide Evidence for a Partial Epileptic Syndrome of Frontal Lobe Origin

Summary: In the pediatric age period, three idiopathic partial epileptic syndromes are recognized: benign childhood epilepsy with centrotemporal spikes, childhood epilepsy with occipital paroxysms, and primary reading epilepsy. All other partial epilepsies are considered cryptogenic, and no other idiopathic partial epilepsies have been recognized. We observed 10 children with tonic partial postural seizures, mainly hypnic, coinciding with a recognizable ictal epileptiform EEG pattern. The children all had normal neuropsychological development before and after seizure onset. The seizures were tractable in all. Onset was in the early pediatric age period; no other type of seizure was recognized. The occurrence of a family history of epilepsy was high. The seizure pattern was typical of supplementary motor area origin. Because of the normal neuropsychological status, high familial incidence of epilepsy, and benign course of this partial epilepsy, we believe it should be considered idiopathic, using the criteria of the International Classification of Epilepsies and Epileptic Syndromes. We therefore suggest the existence of a partial idiopathic epileptic syndrome having onset with seizures of frontal lobe origin.     

Lamotrigine Therapy for Partial Seizures: A Multicenter, Placebo-Controlled, Double-Blind, Cross-Over Trial

Summary: The efficacy and safety of lamotrigine (LTG), a new antiepileptic drug (AED), were evaluated in a multicenter, randomized, double-blind, placebo-controlled, cross-over study of 98 patients with refractory partial seizures. Each treatment period lasted 14 weeks. Most patients were titrated to a LTG maintenance dose of 400 mglday. Seizure frequency with LTG decreased by ≥50%, as compared with placebo, in one fifth of patients. Overall median seizure frequency decreased by 25% with LTG as compared with placebo (p < 0.001). With LTG, the number of seizure days decreased by 18% as compared with placebo (p < 0.01), and investigator global evaluation of overall patient clinical status favored LTG by 2: 1 (p = 0.013). Plasma LTG concentrations appeared to be linearly related to dosage. LTG had no clinically important effects on the plasma concentrations of concomitant AEds. Adverse experiences were generally minor and most frequently were CNS-related (e.g., ataxia, dizziness, diplopia, headache). Most were transient and resolved without discontinuing treatment. Five patients withdrew as a result of adverse experiences while receiving LTG, including 3 patients with rash. One placebo patient was also withdrawn because of rash. The addition of twice-daily LTG to an existing AED regimen was safe, effective, and well tolerated in these medically refractory partial seizure patients.     

Correlative Study of Interictal Electroencephalogram and Aura in Complex Partial Seizures

To understand further relationships of the interictal electroencephalogram to the aura in complex partial seizures (CPS), we studied the interictal EEG and aura in 144 patients with CPS. The ages of the patients studied ranged from 31 to 80 years (average 52.44 years). The duration of seizures ranged from 1 to 60 years (average 15.69 years). Seventy patients (49%) reported auras which were classified according to the guidelines recommended by the Commission of the International League Against Epilepsy. Statistical analysis revealed no relationship between presence, laterality, or localization of EEG abnormality and the number or type of aura. The results emphasize that more factors than electrophysiologic localization alone participate in the determination of aura in CPS. Our data support the position that aura has, at most, a limited relationship to lateralization or localization of interictal cerebral dysfunction in CPS.     

Transient Global Amnesia as a Postictal State from Recurrent Partial Seizures

A 60-year-old patient had a 3-year history of recurrent memory disturbances. The video electroencephalographic (EEG) recording of one attack showed that the amnesic state, which clinically resembled transient global amnesia, was characterized by a normal EEG tracing followed by electroclinical complex partial seizures. We suggest that "epileptic" transient global amnesia is postictal in nature.     

Classification of Partial Epilepsies According to the Symptomatology of Seizures: Practical Value and Prognostic Implications

Among 1,000 outpatient epileptics who visited the Epilepsy Center of Bologna consecutively from 1974 to 1978, 596 cases of partial epilepsy (PE) were chosen, representing 62.9% of all cases classified according to the International Classification of epilepsies. Fifty-four of these cases (5.7%) of those classifiable) that were affected by benign infantile epilepsy with rolandic spikes were not analyzed further. The remaining cases were divided up into three groups based on the symptomatology of the seizures: (1) partial elementary epilepsy (PEE), 102 cases (10.8%); (2) partial complex epilepsy (PCE), 332 cases (35%); and (3) partial secondarily generalized epilepsy (PSGE), 108 cases (11.4%). The three groups were compared according to the parameters that distinguish recognized epileptic syndromes, in order to see whether they constitute autonomous nosographic entities. Among the three groups, significant differences did not arise with regard to the incidence of single lesional etiological factors, the age of onset of the epilepsy, the neurological context, and the general features of interictal EEG. PSGE instead differs significantly from the other two forms for the minor severity of the epilepsy at first examination and for its more favorable course: after at least 2 years of follow-up under treatment, the epilepsy appeared to be controlled in 60.6% of the cases with PSGE, in 31.6% of those with PEE, and in 37.5% of those with PCE (p less than 0.05). For those with PE, globally considered, only three parameters have a favorable prognostic value: the brief duration of the epilepsy at the first observation, the rarity of the seizures, and the presence of only one type of seizure.     

Pilot Study of Zonisamide (1,2-Benzisoxazole-3-methanesulfonamide) in Patients with Refractory Partial Seizures

A new anticonvulsant compound, zonisamide (1,2 benzisoxazole-methanesulfonamide), was studied in 10 adults with medically refractory partial seizures. Following a single oral dose of 400 mg, peak plasma levels occurred an average of 2.8 h after dosing, and the mean clearance from plasma was 2.34 L/h. Whole blood concentrations were higher than plasma concentrations because of red blood cell binding. Steady-state plasma concentrations were higher than predicted from a linear kinetic model. In most patients, seizure frequency was reduced after zonisamide was substituted for a standard antiepileptic drug. Dose-related reversible side effects in the central nervous and gastrointestinal systems were observed. Most patients tolerated doses between 5.2 and 12.5 mg/kg/day.     

Pregabalin As Adjunctive Therapy for Partial Seizures

Summary:  The efficacy and safety of pregabalin as adjunctive therapy for patients with partial epilepsy with or without secondary generalization has been studied in three randomized, double-blind, placebo-controlled trials involving 1,052 patients. Patients (≥12 years of age) participating in the trials were highly refractory to treatment, experiencing at least six seizures and no 4-week seizure-free period during the 8-week baseline phase, even though 73% received at least two antiepileptic drugs and 23% received three. Each fixed-dose study was 12 weeks in duration. In Study 1, patients received pregabalin 50, 150, 300, or 600 mg/day given two times daily with no titration period. Studies 2 and 3 had a 1-week titration to dose levels of 150 and 600 mg/day given three times daily (Study 2), 600 mg/day given two times daily, and 600 mg/day given three times daily (Study 3). Pregabalin, at 150, 300, and 600 mg/day, was significantly superior to placebo in reducing seizure frequency with a clear dose–response relationship. Responder rates, defined as the percentage of patients with ≥50% reduction in seizure frequency from baseline, approached 50% at 600 mg/day. In the effective dose range (150–600 mg/day), seizure freedom in the last 28 days of treatment was 3–17%. There was no difference between two times daily and three times daily dosing regimens. Efficacy was apparent as early as week one. The most commonly reported adverse events were CNS related, and either mild or moderate in intensity and generally self limiting. Few patients (≤5% in any treatment group) discontinued due to lack of efficacy. These results indicate that pregabalin is highly effective as adjunctive therapy in the treatment of patients with partial seizures with or without secondary generalization.     

Tiagabine: Efficacy and Safety in Adjunctive Treatment of Partial Seizures

PURPOSE: To assess the efficacy and safety of tiagabine (TGB), a new antiepileptic drug (AED), as add-on therapy in patients with refractory partial seizures. METHODS: This response-dependent study used an open-label screening phase (in which patients were titrated to their optimal TGB dose, < or =64 mg/day) followed by a double-blind, placebo-controlled, crossover phase. Initial eligibility criteria included (a) seizures inadequately controlled by existing AEDs, and (b) six or more partial seizures during an 8-week baseline period. Patients showing benefit from TGB (> or =25% reduction in total seizure rate relative to baseline) were eligible for randomization into the double-blind phase, which comprised two 7-week assessment periods separated by a 3-week crossover period. RESULTS: Forty-four (50%) of the 88 enrolled patients entered the double-blind phase of the study during which there were significant reductions compared with placebo in all partial (p < 0.01), complex partial (p < 0.001), and secondarily generalized tonic-clonic seizure rates (p < 0.05). Thirty-three percent of patients experienced a reduction of > or =50% in the all partial seizure rate. Eight (22%) patients receiving TGB during the double-blind phase reported adverse events, of which dizziness and incoordination were the most frequent. Three patients withdrew from treatment during the double-blind phase because of adverse events; two during treatment with TGB and one during treatment with placebo. TGB did not affect plasma concentrations of other coadministered AEDs. CONCLUSIONS: TGB was significantly better than placebo in terms of seizure rate reduction and was generally well-tolerated in patients with difficult to control seizures.