Memantine in moderate to severe Alzheimer's disease: an observational post-marketing study.

Memantine is an N-methyl-D: -aspartate (NMDA) receptor antagonist, approved for the treatment of moderate to severe Alzheimer's disease (AD). We conducted a 4-month observational, post-marketing, Austrian study of memantine in 377 outpatients with moderate to severe AD. In this 'real-life' setting, memantine was well-tolerated, and produced benefits in cognition (Mini-Mental State Examination), activities of daily living (Activities of Daily Living score), and global function (Clinical Global Impression scale). Treatment effects were apparent in both pre-treated and treatment-naïve patient subgroups.

Randomized, crossover, single-blind, placebo-controlled, human pharmacology clinical trial with desoxypeganine, a new cholinesterase and selective MAO-A inhibitor: multiple-dose pharmacokinetics.

UNLABELLED: Desoxypeganine, a naturally occurring alkaloid, is being developed for its potential utility in the pharmacological treatment of alcohol abuse to reduce craving and depression in alcohol abusers, and might also be useful as a smoking cessation aid. During the preclinical development it was characterized as a cholinesterase inhibitor, acting preferentially on butyrylcholinesterase, and as a selective inhibitor of monoamine oxidase A but not monoamine oxidase B. OBJECTIVE: The aim of the present human pharmacology clinical trial was to assess the oral bioavailability, pharmacokinetic profile and tolerability of desoxypeganine, administered in a multiple-dose regimen to healthy volunteers. SUBJECTS AND METHODS: Eighteen healthy adult volunteers of both sexes received placebo, 50 mg and 100 mg desoxypeganine (b.i.d. for 3 days) in a single-blind, crossover, randomized manner. Main pharmacokinetic parameters after single and multiple doses were estimated. Clinical tolerability and clinical laboratory safety, including effect on QTc interval, were assessed. RESULTS: Non-compartmental estimations of Cmax, AUC, tmax, t1/2 and MRT at 12-h intervals are given. No significant dose effect was observed in tmax, t1/2 and MRT. Cmax and AUC are approximately double with the dose of 100 mg comparing with the dose of 50 mg. A significant increase (p < 0.05) on Cmax and AUC was also obtained with the highest dose administered in comparison with the lowest one, revealing a slight but clinically insignificant accumulation. Steady state of drug concentration was reached in both genders during the study period. Plasma protein binding of desoxypeganine amounted to approximately 18%. No severe adverse events were recorded and none of the subjects suffered from any adverse event that led to withdrawal from the study. Most frequently recorded adverse event was dizziness. No significant effects of desoxypeganine on vital signs, laboratory parameters or QTc interval were observed. CONCLUSIONS: The present clinical trial describes the pharmacokinetic profile of two doses of desoxypeganine, administered orally in multiple dose to healthy volunteers. The drug was well tolerated without any severe clinical, clinical laboratory, or ECG adverse events being recorded.

Phase I clinical trial with desoxypeganine, a new cholinesterase and selective MAO-A inhibitor: tolerance and pharmacokinetics study of escalating single oral doses.

Desoxypeganine (DOP) is a natural alkaloid that has been characterized as a cholinesterase inhibitor and a selective inhibitor of monoamine oxidase A. DOP has been investigated for its potential utility in the pharmacological treatment of alcohol abuse and as a smoking cessation aid. The aim of this clinical trial was to evaluate the tolerance and single-dose pharmacokinetic profile of DOP in healthy human volunteers. The study was an open-label, dose-escalation, phase I clinical trial involving the administration of increasing single oral doses of DOP (50, 100, 150 and 200 mg). The study was conducted according to the Declaration of Helsinki and Good Clinical Practice. Eighteen healthy adult volunteers (8 males and 10 females, age ranging 20-30 years) were recruited. DOP was administered sequentially, escalating in single doses of 50, 100, 150 and 200 mg in four experimental sessions with a washout period of at least 1 week between them. Progress to the next dose was allowed only if the previous dose was tolerated. Pharmacokinetic parameters were determined using noncompartmental methods. Clinical and analytical safety was assessed throughout the study, and QTc intervals were measured at regular intervals. The main pharmacokinetic parameters and renal excretion are described. No serious adverse events were registered, and none of the subjects discontinued the study because of lack of tolerance. All the adverse events recorded were mild to moderate and increased with the dose. The ECG measurements revealed that even at a higher dose, the QTc interval remained below the safety threshold. In summary, this first phase I study indicates that DOP has linear and dose-proportional pharmacokinetics, satisfactory oral bioavailability and plasma half-life and renal excretion. Also, DOP has shown an adequate safety profile that allows the continuation of clinical development.

Data from the VITA Study do not support the concept of vascular depression.

OBJECTIVE: Cerebrovascular lesions that are apparent in magnetic resonance scans and regioselective atrophy of the brain have been proposed as a causative or exacerbating factor in depression with late-life onset. The objective of this study was to investigate whether deep white matter or periventricular hyperintensities, small ischemic lesions, and brain atrophy contribute to late-onset depression in the nondemented elderly. METHOD: Based on a group of 606 individuals of identical age (75.8 years, standard deviation: 0.45 years) residing in two districts of Vienna, the authors built a case-control cohort (ratio: 1:4) consisting of 51 individuals with late-onset major or minor depression matched with 204 subjects of identical gender and education status without depression, resulting in two groups that were homogenous with respect to age, place of residence, gender, and education. Scores for focal brain lesions, mediotemporal lobe atrophy, and ventricular enlargement as well as risk factors for vascular disease were compared with cognition and depression status. RESULTS: Depressed individuals had significantly lower scores than nondepressed subjects in all measures of cognitive and executive function. No significant relation was found between a diagnosis of depression and any type of discrete brain lesions, but measures of brain atrophy (Cella Media indices, mediotemporal atrophy) showed a clear statistical relation to depression. No relationship was found between depression and lipid parameters. CONCLUSION: The authors found no indication that white matter hyperintensities or minor ischemic lesions played a role in our depressed cohort, casting doubt on the vascular hypothesis of late-onset depression.

Genomics and dementia--new drug targets ahead?

Pharmacogenomics--the application of genomic technologies such as gene sequencing and gene expression analysis to drugs--is beginning to make its impact on central nervous system drug development. The mapping of genes (including their polymorphisms) and their expression in normal and disease states to discover new drug targets will also change the scenery of dementia therapeutics' development completely because it uses a "bottom-up" strategy, identifying genes whose expression is changed in dementia or by drug therapy. Drugs identified this way should be mechanistically novel, more potent and specific, and probably quicker to develop. Pharmacogenomics can however also greatly contribute to the improvement of drugs targeting currently known receptors and enzymes.