Topiramate placebo-controlled dose-ranging trial in refractory partial epilepsy using 600-, 800-, and 1,000-mg daily dosages

We conducted a multicenter, double-blind, randomized, parallel, placebo-controlled trial in 190 patients to evaluate the safety and efficacy of three dosages of topiramate (600, 800, and 1,000 mg/day) as adjunctive therapy for patients with refractory partial epilepsy. During an 18-week double-blind treatment period, median percent reductions from baseline in average monthly seizure rates were 1% for placebo, 41% for topiramate 600 mg/day and topiramate 800 mg/day, and 38% for topiramate 1,000 mg/day. There was a 50% or greater reduction from baseline in seizure frequency in 9% of patients in the placebo group and in 44% for topiramate 600 mg/day, 40% for topiramate 800 mg/day, and 38% for topiramate 1,000 mg/day. No placebo patients were improved by 75 to 100% in seizure frequency, whereas 20% of the topiramate patients were improved to this degree. All intent-to-treat drug-placebo comparisons including seizure reduction, percent responders, and investigator and patient global evaluations significantly (p &lt;or=to 0.02) favored topiramate. Treatment-emergent adverse events consisted mainly of neurologic symptoms commonly observed during antiepileptic drug (AED) therapy. Sixteen percent of patients on topiramate discontinued therapy due to adverse events. Results of this study indicate that topiramate is a highly efficacious and generally well tolerated new AED. When large groups of patients are compared, incremental efficacy in the add-on setting is not observed at topiramate dosages above 600 mg/day; however, higher doses may prove beneficial to individual patients who tolerate them.NEUROLOGY 1996;46: 1678-1683</jats:p

A double-blind, randomized trial of topiramate in Lennox–Gastaut syndrome

Objective: To evaluate the efficacy and safety of topiramate as adjunctive therapy for Lennox–Gastaut syndrome in a multicenter, double-blind, placebo-controlled trial.Background: Conventional antiepileptic drugs are frequently ineffective against multiple-seizure types of Lennox–Gastaut syndrome.Methods: Ninety-eight patients &gt;1 year to &lt;30 years of age, with slow spike-and-wave patterns on EEG, seizure types including drop attacks, and either a history of or active atypical absence seizures, were assigned to an 11-week, double-blind treatment phase with either topiramate or placebo. Topiramate was titrated to target doses of approximately 6 mg/kg/d.Results: For drop attacks, the most severe seizures associated with this syndrome, the median percentage reduction from baseline in average monthly seizure rate was 14.8% for the topiramate group and −5.1% (an increase) for the placebo group (p = 0.041). Topiramate-treated patients demonstrated greater improvement in seizure severity than did placebo-treated patients based on parental global evaluations (p = 0.037). The percentage of patients with a ≥50% reduction from baseline in major seizures (drop attacks and tonic-clonic seizures) was greater in the topiramate group (15/46 or 33%) than in the control group (4/50 or 8%; p = 0.002). The most common adverse events in both groups were CNS related; there were no discontinuations from topiramate therapy due to adverse events.Conclusions: Topiramate adjunctive therapy was effective in reducing the number of drop attacks and major motor seizures and in improving seizure severity as determined by parental global evaluation.</jats:p

Porphyromonas gingivalis lipopolysaccharide is poorly recognized by molecular components of innate host defense in a mouse model of early inflammation

Porphyromonas gingivalis is a gram-negative bacterium that is associated with periodontitis. It has been hypothesized that destruction of bone and periodontal connective tissue is associated with colonization of the subgingival crevicular space by P. gingivalis, although how these bacteria overcome innate host defenses is largely unknown. To examine the early cellular and molecular events of P. gingivalis interaction with host tissues, we compared lipopolysaccharide (LPS) isolated from this bacterium with Escherichia coli LPS, a potent inflammatory mediator, in a mouse model of acute inflammation. In these studies, mice were given intramuscular injections of either P. gingivalis LPS or E. coli LPS and then sacrificed after 4 h. Reverse transcriptase-PCR analysis showed that expression of mRNAs for E- and P-selectins was higher in E. coli LPS-injected muscles than in P. gingivalis LPS-injected or control phosphate-buffered-saline-injected muscles. Similarly, monocyte chemotactic protein 1 and fibroblast-induced cytokine mRNAs were expressed in E. coli LPS-injected muscles whereas their expression was reduced or absent in P. gingivalis LPS-injected samples. These results were confirmed by in situ hybridization whereby stronger hybridization for selectin mRNAs was observed in the endothelium of capillaries from E. coli LPS-injected samples than in that from P. gingivalis LPS-injected muscles. In addition, many monocytes expressing monocyte chemotactic protein 1 mRNA and polymorphonuclear leukocytes expressing fibroblast-induced cytokine mRNA were observed in E. coli LPS-injected muscles whereas only a few cells were identified in P. gingivalis LPS-injected muscles. These results demonstrate that compared with E. coli, P. gingivalis has a low biologically reactive LPS as measured by its weak activation of inflammation. This may allow P. gingivalis to evade innate host defense mechanisms, resulting in colonization and chronic disease.</jats:p