Crossover trial of pagoclone and placebo in patients with DSM-IV panic disorder.

Pagoclone is a cyclopyrrolone that is believed to act as a partial agonist at the gamma-aminobutyric acid (GABA)-A/benzodiazepine (BDZ) receptor. In theory, such partial agonists should be anxiolytic but lack the adverse side-effects of sedation, tolerance and withdrawal associated with full GABA-A/BDZ agonists. The objective of the randomized double-blind crossover study was to assess whether pagoclone was an effective anti-panic agent and also to assess its side-effect profile. Patients recruited had a diagnosis of Panic Disorder (DSM-IV) with at least one panic attack per week. Following a 2-week screening period, patients entered a 6-week trial consisting of two 2-week treatment periods, each followed by a 1-week washout. Patients were randomly assigned to receive either pagoclone 0.1 mg t.d.s. or placebo on their first treatment period and the converse on their second. The primary measure was daily panic attack dairy. Fourteen patients completed the study, the mean number of panic attacks during screening was 5.8+/-0.8 (SEM), this fell to 3.6+/-0.5 during treatment with pagoclone (p = 0.05) and 4.3+/-0.8 with placebo (p = 0.14). There was no significant difference on direct comparison of pagoclone with placebo or in any of the secondary measures (including Rickels withdrawal scale) or the adverse event profiles. The study provides preliminary evidence that pagoclone has anxiolytic properties in the absence of typical BDZ side-effects. This is consistent with its theoretical mode of action as a partial agonist at the GABA(A)/BDZ receptor.

Citicoline (CDP-choline): mechanisms of action and effects in ischemic brain injury.

Citicoline is approved in Europe and Japan for use in stroke, head trauma and other neurological disorders. It is presently being evaluated in phase II/III stroke trials in the United States. Exogenous administration of CDP-choline provides both choline and cytidine which access the brain and serve as substrates for the synthesis of phosphatidylcholine, a primary neuronal membrane component; the choline also enhances brain acetylcholine synthesis. Membrane repair and regeneration is necessary for recovery from stroke. Furthermore, citicoline may alleviate free fatty acid-induced toxicity which accompanies ischemic insult. Data from many pre-clinical and clinical trials support the hypothesis that citicoline may be a safe and effective treatment for stroke.