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PubMed2007

Lacosamide.

Lacosamide is a new chemical entity being investigated as an adjunctive treatment for epilepsy, as well as monotherapy for diabetic neuropathic pain. Lacosamide appears to have a dual mode of action: selective enhancement of sodium channel inactivation and modulation of collapsin response mediator protein-2. Rapidly and completely absorbed after oral administration, lacosamide has an elimination half-life of approximately 13 hours and a low potential for drug interactions. Additionally, lacosamide exhibits linear, dose-proportional pharmacokinetics with low intra- and interpatient variability. Randomized controlled trials of adjunctive lacosamide (200, 400, and 600 mg/day) have demonstrated statistically significant reduction in median seizure frequency compared with placebo. In addition, 50% responder rates for lacosamide (400 and 600 mg/day) were statistically superior to placebo. The most frequently reported adverse events (> or =10% of lacosamide-treated patients) included dizziness, headache, and nausea. A double-blind, double-dummy randomized trial of intravenous lacosamide (30- and 60-minute infusion) as replacement for oral lacosamide showed that the safety and tolerability profiles were comparable for intravenous and oral lacosamide. The efficacy and safety results from completed clinical trials, as well as the favorable pharmacokinetic profile, suggest that lacosamide may represent a significant advance in antiepileptic drug therapy.

Acetamides↗

PubMed2005

Tumor necrosis factor-alpha-dependent expression of phosphodiesterase 2: role in endothelial hyperpermeability.

The pleiotropic cytokine tumor necrosis factor-alpha (TNF-alpha) and thrombin lead to increased endothelial permeability in sepsis. Numerous studies demonstrated the significance of intracellular cyclic nucleotides for the maintenance of endothelial barrier function. Actions of cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) are terminated by distinct cyclic nucleotide phosphodiesterases (PDEs). We hypothesized that TNF-alpha could regulate PDE activity in endothelial cells, thereby impairing endothelial barrier function. In cultured human umbilical vein endothelial cells (HUVECs), we found a dramatic increase of PDE2 activity following TNF-alpha stimulation, while PDE3 and PDE4 activities remained unchanged. Significant PDE activities other than PDE2, PDE3, and PDE4 were not detected. TNF-alpha increased PDE2 expression in a p38 mitogen-activated protein kinase (MAPK)-dependent manner. Endothelial barrier function was investigated in HUVECs and in isolated mice lungs. Selective PDE2 up-regulation sensitized HUVECs toward the permeability-increasing agent thrombin. In isolated mice lungs, we demonstrated that PDE2 inhibition was effective in preventing thrombin-induced lung edema, as shown with a reduction in both lung wet-to-dry ratio and albumin flux from the vascular to bronchoalveolar compartment. Our findings suggest that TNF-alpha-mediated up-regulation of PDE2 may destabilize endothelial barrier function in sepsis. Inhibition of PDE2 is therefore of potential therapeutic interest in sepsis and acute respiratory distress syndrome (ARDS).

Animals↗