Ovidiu Bajenaru

Effect of glatiramer acetate on conversion to clinically definite multiple sclerosis in patients with clinically isolated syndrome (PreCISe study): a randomised, double-blind, placebo-controlled trial

BACKGROUND Glatiramer acetate, approved for the treatment of relapsing-remitting multiple sclerosis, reduces relapses and disease activity and burden monitored by MRI. We assessed the efficacy of early treatment with glatiramer acetate in delaying onset of clinically definite multiple sclerosis. METHODS In this randomised, double-blind trial, undertaken in 80 sites in 16 countries, 481 patients presenting with a clinically isolated syndrome with unifocal manifestation, and two or more T2-weighted brain lesions measuring 6 mm or more, were randomly assigned to receive either subcutaneous glatiramer acetate 20 mg per day (n=243) or placebo (n=238) for up to 36 months, unless they converted to clinically definite multiple sclerosis. The randomisation scheme used SAS-based blocks stratified by centre, and patients and all personnel were masked to treatment assignment. The primary endpoint was time to clinically definite multiple sclerosis, based on a second clinical attack. Analysis was by intention to treat. A preplanned interim analysis was done for data accumulated from 81% of the 3-year study exposure. This study was registered with ClinicalTrials.gov, number NCT00666224. FINDINGS All randomly assigned participants were analysed for the primary outcome. Glatiramer acetate reduced the risk of developing clinically definite multiple sclerosis by 45% compared with placebo (hazard ratio 0.55, 95% CI 0.40-0.77; p=0.0005). The time for 25% of patients to convert to clinically definite disease was prolonged by 115%, from 336 days for placebo to 722 days for glatiramer acetate. The most common adverse events in the glatiramer acetate group were injection-site reactions (135 [56%] glatiramer acetate vs 56 [24%] placebo) and immediate post-injection reactions (47 [19%] vs 12 [5%]). INTERPRETATION Early treatment with glatiramer acetate is efficacious in delaying conversion to clinically definite multiple sclerosis in patients presenting with clinically isolated syndrome and brain lesions detected by MRI. FUNDING Teva Pharmaceutical Industries, Israel.

Blood-brain barrier alterations in ageing and dementia

The current pathogenic scenarios of different types of dementia are based on a number of common mechanisms of neurodegeneration, such as accumulation of abnormal proteins (within or outside cells), mitochondrial dysfunction and oxidative stress, calcium homeostasis dysregulation, early synaptic disconnection and late apoptotic cell death. Ageing itself is associated with mild cognitive deterioration, probably due to subtle multifactorial changes resulting in a global decrease of a functional brain reserve. Increased age is a risk factor for neurodegeneration and key pathological features of dementia can also be found in aged brains. One of the underexplored brain structures in ageing and dementia is the blood-brain barrier (BBB), a complex cellular gate which regulates tightly the transport of molecules into and from the central nervous system. Disruption of this barrier is now increasingly documented not only in brain vascular disease but also in ageing and neurodegenerative disorders. To date, such evidence points mainly at an association between various dementia forms and disruption of the BBB. But, in reviewing such results, and taking into account the exquisite sensitivity of neuronal function to the composition of the interstitial brain fluid (IBF), which is regulated by the BBB, we would like to propose the existence of a possible causal link between alterations of BBB and conditions associated with cognitive decline.

Effects of early treatment with glatiramer acetate in patients with clinically isolated syndrome

Background: The placebo-controlled phase of the PreCISe study showed that glatiramer acetate delayed onset of clinically definite multiple sclerosis (CDMS) in patients with clinically isolated syndrome and brain lesions on MRI. Objective: To compare the effects of early versus delayed glatiramer acetate treatment in the open-label phase of PreCISe. Methods: Patients with a clinically isolated syndrome suggestive of MS with unifocal manifestation and ≥2 T2-weighted brain lesions were randomized to receive glatiramer acetate 20 mg/d (early-treatment, n=198) or placebo (delayed-treatment, n=211) for 36 months or until conversion to CDMS, followed by open-label glatiramer acetate treatment for two years. Results: Early glatiramer acetate treatment reduced CDMS conversion risk by 41% (hazard ratio 0.59, 95% confidence interval 0.44–0.80; p=0.0005) versus delayed-treatment, and was associated with a 972-day delay (185%) in conversion to CDMS, less brain atrophy (−28%, p=0.0209), fewer new T2 lesions/year (−42%, <0.0001) and lower T2 lesion volume (−22%, p=0.0005) versus delayed treatment. Adverse events were consistent with the established safety profile of glatiramer acetate. Conclusions: Effects of early glatiramer acetate treatment on the rate of conversion to CDMS and on MRI measures of disease activity and lesion burden support initiating glatiramer acetate treatment soon after the first clinical symptoms suggestive of MS and continuing treatment to sustain benefits.

Dantrolene protects neurons against kainic acid induced apoptosis in vitro and in vivo

Apoptotic cell death induced by kainic acid (KA) in cultures of rat cerebellar granule cells (CGC) and in different brain regions of Wistar rat pups on postnatal day 21 (P21) was studied. In vitro, KA (100–500 μM) induced a concentration‐dependent loss of cell viability in MTT assay and cell death had apoptotic morphology as studied by chromatin staining with propidium iodide (PI). In vivo, twenty‐four hours after induction of status epilepticus (SE) by an intraperitoneal KA injection (5 mg/kg) we quantified apoptotic cells in hippocampus (CA1 and CA3), parietal cortex and cerebellum using PI staining and terminal deoxynucleotidyl transferase‐mediated dUTP nick end labeling (TUNEL) technique. We report that dantrolene, a specific ryanodine receptor antagonist, was able to significantly reduce the apoptotic cell death in CGC cultures and in hyppocampal CA1 and parietal cortex regions. Our finding can be valuable for neuroprotective therapy strategies in patients with repeated generalized seizures or status epilepticus.

Occludin is overexpressed in Alzheimer's disease and vascular dementia

The tight junctions (TJs) are key players in the control of blood‐brain barrier (BBB) properties, the most complex TJs in the vascular system being found in the endothelial cells of brain capillaries. One of the main TJs proteins is occludin, which anchors plasma membranes of neighbour cells and is present in large amounts in the brain endothelia. Previous studies demonstrated that disruption of BBB in various pathological situations associates with changes in occludin expression, and this change could be responsible for malfunction of BBB. Therefore in this study, applying an immunohistochemical approach, we decided to explore the occludin expression in frontal cortex (FC) and basal ganglia in ageing control, Alzheimers disease (AD), and vascular dementia (VD) brains, as far as all these pathologies associate microangiopathy and disruption of BBB. Strikingly, we found selected neurons, astrocytes and oligodendrocytes expressing occludin, in all cases studied. To estimate the number of occludin‐expressing neurons, we applied a stereological approach with random systematic sampling and the unbiased optical fractionator method. We report here a significant increase in ratio of occludin‐expressing neurons in FC and basal ganglia regions in both AD and VD as compared to ageing controls. Within the cerebral cortex, occludin was selectively expressed by pyramidal neurons, which are the ones responsible for cognitive processes and affected by AD pathology. Our findings could be important in unravelling new pathogenic pathways in dementia disorders and new functions of occludin and TJs.

Cerebrolysin and Recovery After Stroke (CARS): A Randomized, Placebo-Controlled, Double-Blind, Multicenter Trial

Background and Purpose— The aim of this trial was to investigate whether stroke patients who receive Cerebrolysin show improved motor function in the upper extremities at day 90 compared with patients who receive a placebo. Methods— This study was a prospective, randomized, double-blind, placebo-controlled, multicenter, parallel-group study. Patients were treated with Cerebrolysin (30 mL/d) or a placebo (saline) once daily for 21 days, beginning at 24 to 72 hours after stroke onset. The patients also participated in a standardized rehabilitation program for 21 days that was initiated within 72 hours after stroke onset. The primary end point was the Action Research Arm Test score on day 90. Results— The nonparametric effect size on the Action Research Arm Test score on day 90 indicated a large superiority of Cerebrolysin compared with the placebo (Mann–Whitney estimator, 0.71; 95% confidence interval, 0.63–0.79; P<0.0001). The multivariate effect size on global status, as assessed using 12 different outcome scales, indicated a small-to-medium superiority of Cerebrolysin (Mann–Whitney estimator, 0.62; 95% confidence interval, 0.58–0.65; P<0.0001). The rate of premature discontinuation was <5% (3.8%). Cerebrolysin was safe and well tolerated. Conclusions— Cerebrolysin had a beneficial effect on function and global outcome in early rehabilitation patients after stroke. Its safety was comparable with that of the placebo, suggesting a favorable benefit/risk ratio. Because this study was exploratory and had a relatively small sample size, the results should be confirmed in a large-scale, randomized clinical trial. Clinical Trial Registration— URL: http://www.clinicaltrialsregister.eu. Unique identifier: 2007-000870-21.

The results of two multicenter, open-label studies assessing efficacy, tolerability and safety of protiramer, a high molecular weight synthetic copolymeric mixture, in patients with relapsing-remitting multiple sclerosis

Objective Two pilot studies were conducted to evaluate safety, tolerability, and efficacy of two doses of Protiramer (TV-5010) in patients with relapsing–remitting multiple sclerosis. Background Both glatiramer acetate and TV-5010 are synthetic copolymers comprised the same four amino acids in a defined molar ratio. TV-5010 has higher average molecular weight than Glatiramer acetate and might be hypothesized that glatiramoids with higher molecular weight might be more immunoreactive than lower molecular weight peptides, thus increasing therapeutic potential and allowing for less frequent dosing. Methods In the two separate studies, after a 10 week pretreatment period, TV-5010 was given subcutaneously once weekly at 15 mg and 30 mg for 36 weeks. The primary end point was a reduction in the number of magnetic resonance imaging active lesions (i.e., T1-weigthed gadolinium-enhancing and new T2-weighted lesions) between the pretreatment period and the end of study. Results Both TV-5010 doses were generally well tolerated. The treatment with TV-5010 at a dose of 15 mg/wk did not show any significant effect. In contrast, in patients treated with at a dose of 30 mg/wk, a significant reduction in the mean number of gadolinium-enhancing (−58.8%; P = 0.0013) and new T2-W (−50%; P = 0.0002) lesions was observed. However, a large decrease in the mean number of both gadolinium-enhancing (−55%) and new T2-W (−40%) lesions during the pretreatment period made difficult the interpretation of the efficacy assessments. Conclusions Further studies are needed to confirm these preliminary data on safety and efficacy of TV-5010 at a weekly dose of 30 mg.

How Does Fingolimod (Gilenya®) Fit in the Treatment Algorithm for Highly Active Relapsing-Remitting Multiple Sclerosis?

Multiple sclerosis (MS) is a neurological disorder characterized by inflammatory demyelination and neurodegeneration in the central nervous system. Until recently, disease-modifying treatment was based on agents requiring parenteral delivery, thus limiting long-term compliance. Basic treatments such as beta-interferon provide only moderate efficacy, and although therapies for second-line treatment and highly active MS are more effective, they are associated with potentially severe side effects. Fingolimod (Gilenya®) is the first oral treatment of MS and has recently been approved as single disease-modifying therapy in highly active relapsing-remitting multiple sclerosis (RRMS) for adult patients with high disease activity despite basic treatment (beta-interferon) and for treatment-naïve patients with rapidly evolving severe RRMS. At a scientific meeting that took place in Vienna on November 18th, 2011, experts from ten Central and Eastern European countries discussed the clinical benefits and potential risks of fingolimod for MS, suggested how the new therapy fits within the current treatment algorithm and provided expert opinion for the selection and management of patients.

Label free sensing platform for amyloid fibrils effect on living cells.

This study presents a multiparametric label-free analysis gathering surface plasmon resonance (SPR) and electrical impedance spectroscopy (EIS) for monitoring the progress of a model epithelial cell culture (Madin Darbey Canine Kidney - MDCK) exposed to a peptide with high bio-medical relevance, amyloid β (Aβ42). The approach surpasses the limitations in using the SPR angle for analyzing confluent cell monolayers and proposes a novel quantitative analysis of the SPR dip combined with advanced EIS as a tool for dynamic cell assessment. Long, up to 48h time series of EIS and SPR data reveal a biphasic cellular response upon Aβ42 exposure corresponding to changes in cell-substrate adherence, cell-cell tightening or cytoskeletal remodeling. The equivalent circuit used for fitting the EIS spectra provided substantiation of SPR analysis on the progress of cell adhesion as well as insight on dynamics of cell-cell junction. Complementary endpoint assays: western blot analysis and atomic force microscopy experiments have been performed for validation. The proposed label free sensing of nonlethal effect of model amyloid protein at cellular level provides enhanced resolution on cell-surface and cell-cell interactions modulated by membrane related protein apparatus, applicable as well to other adherent cell types and amyloid compounds.

Persistence of the effects of Cerebrolysin on cognition and qEEG slowing in vascular dementia patients: results of a 3-month extension study.

The maintenance of the effects of Cerebrolysin, a peptidergic compound with neurotrophic activity, on cognitive performance and qEEG activity was investigated through a 12-week, open-label extension of a 4-week, randomised, placebo-controlled pilot study. Thirty-three out of 41 patients with mild-to-moderate severe probable vascular dementia (VaD) according to NINDS-AIREN participating in the double-blind phase of the study were also assessed at the follow-up visit at week 16. Patients received i.v. infusions of Cerebrolysin (10 or 30 mL) or placebo (saline) 5 days/week for 4 weeks. Neuropsychological evaluations and qEEG recordings were done at baseline, week 4 and week 16. The mean change in score from baseline in the ADAS-cog+ and the slow-to-fast qEEG power ratio (PR), used as an index of qEEG slowing, were the two primary endpoints. Correlations between changes in cognition and qEEG induced by the treatment were also assessed. At the week 16 follow-up visit, Cerebrolysin improved (p<0.05) cognitive performance at the 10-mL and 30-mL doses and reduced qEEG slowing significantly (p<0.05) at the 30-mL dose with respect to the placebo. In addition, a significant (p<0.05) positive correlation between the change from the baseline qEEG PR and ADAS-cog+ variables was observed at week 16. These results indicate a persistence of the beneficial effects of Cerebrolysin on cognition and qEEG activity in VaD patients for at least 12 weeks after treatment cessation, and they suggest the potential utility of qEEG parameters as biomarkers for VaD clinical trials.