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BACKGROUND: Previous reports have suggested left hemispheric dominance for maintaining consciousness, although there is controversy over this claim. OBJECTIVE: To compare early impairment of level of consciousness between patients with right and left hemispheric stroke. METHODS: Data from 564 patients with ischaemic stroke enrolled in the placebo arm of a trial of a putative neuroprotectant were analysed. All patients had major hemispheric stroke with cortical dysfunction, visual field deficit, and limb weakness, with symptom onset within 12 hours of enrolment. Patients were prospectively evaluated on a predefined scale (1-6; 1 = fully awake, higher scores representing greater impairment) to measure level of consciousness at multiple time points over the initial 24 hours after presentation. The National Institutes of Health (NIH) stroke scale score at presentation and infarct volume at 30 days were determined. RESULTS: Some degree of impairment in level of consciousness was observed in 409 of the 564 patients (73%). Median maximum sedation score was 2 for both right and left hemispheric stroke (p = 0.91). Mean sedation score over 24 hours was 1.5 for both right and left stroke (p = 0.75). There was no difference between level of consciousness scores in right and left stroke at any individual time point during the 24 hour monitoring period. No association between side and impairment in level of consciousness was seen after adjustment for stroke severity and infarct volume. CONCLUSIONS: In contrast to previous reports, there was no evidence for hemispheric dominance for consciousness in the setting of a major hemispheric stroke.

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BACKGROUND AND PURPOSE: A previous trial (the Clomethiazole Acute Stroke Study) generated the hypothesis that clomethiazole is effective in patients with a major ischemic stroke (total anterior circulation syndrome), and this was tested in the present study. METHODS: A total of 1198 patients with major ischemic stroke and a combination of limb weakness, higher cortical dysfunction, and visual field deficits were randomly assigned to clomethiazole (68 mg/kg IV over 24 hours) or placebo. The study drug was initiated within 12 hours of symptom onset. Functional outcome and neurological recovery were assessed at days 7, 30, and 90, with the proportion of patients with a Barthel Index > or =60 at last follow-up as the primary outcome measure. RESULTS: The patients were randomly assigned equally, and the two treatment groups were well matched for baseline characteristics, including stroke severity (mean National Institutes of Health Stroke Scale score 16.9+/-5.2). Ninety-six percent were classified as total anterior circulation syndrome. The proportion of patients reaching a Barthel Index score of > or =60 was 42% in the clomethiazole-treated group and 46% in the placebo-treated group (odds ratio, 0.81; 95% CI, 0.62 to 1.05; P=0.11). There was no evidence of efficacy on any secondary outcome variables (modified Rankin Score, National Institutes of Health Stroke Scale, Scandinavian Stroke Scale, and 30-day CT infarct volumes) compared with placebo. Subgroup analysis showed a similar lack of treatment effect in patients treated early (<6 hours) and in those treated later (6 to 12 hours). Somnolence was an expected pharmacological effect of clomethiazole, and this occurred during treatment as an adverse event in half of the patients randomly assigned to study drug. CONCLUSIONS: The target population was selected, and sufficient drug was given to produce the expected pharmacological effect in the brain. Clomethiazole does not improve outcome in patients with major ischemic stroke.

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OBJECTIVE: To assess the safety of tissue-type plasminogen activator (t-PA) plus clomethiazole in patients with acute ischemic stroke and determine the feasibility of combination stroke therapy. BACKGROUND: Clomethiazole is a neuroprotectant that appeared to improve outcome in patients with clinical deficits of a major stroke (total anterior circulation syndrome [TACS]) in a previous study, the Clomethiazole Acute Stroke Study (CLASS). Combining a neuroprotectant such as clomethiazole with thrombolysis may augment the beneficial effects of the two agents. CLASS-t-PA (CLASS-T) was a pilot study to explore the safety of the combination and the feasibility of performing combination treatment in the setting of acute ischemic stroke. METHODS: In a randomized, double-blind design (stratified for age, severity at admission, and time since onset of stroke), all patients received 0.9 mg/kg t-PA beginning within 3 hours of stroke onset and then either 68 mg/kg clomethiazole (n = 97) IV over 24 hours or placebo (n = 93) beginning within 12 hours of stroke onset. Patients were followed for 90 days. The main measures of safety were mortality and serious adverse events, and the main measure of functional outcome was the Barthel Index. RESULTS: The number of serious adverse event reports was 47 in the clomethiazole group and 48 in the placebo group. Death during the 90 days after treatment occurred in 15 clomethiazole and nine placebo patients (p = 0.26). Sedation was reported as an adverse event during therapy in 42% of clomethiazole patients vs 13% of placebo patients. The proportion of patients with TACS was 53% in the clomethiazole group and 41% in the placebo group. In the TACS subgroup, 52.9% of the clomethiazole patients scored a Barthel Index greater than 60 vs 44.7% of placebo patients (odds ratio 1.39; 95% CI 0.60 to 3.23). CONCLUSION: In this pilot study, there were no safety concerns related to the combination of t-PA and clomethiazole. The combination paradigm proved feasible, although many patients received clomethiazole several hours after thrombolysis; future studies must require prompt administration of the neuroprotectant either before or during administration of the thrombolytic. Patients with major strokes (TACS) may have the potential to benefit from the combination of t-PA and clomethiazole.

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BACKGROUND AND PURPOSE: Clomethiazole is a neuroprotective drug that enhances gamma-aminobutyrate type A (GABA(A)) receptor activity. Its efficacy and safety were tested in the CLomethiazole Acute Stroke Study (CLASS). The protocol allowed a CT scan to be done after randomization but within 7 days of stroke onset to minimize delays before start of treatment. Ninety-five of the 1360 patients randomized were diagnosed as having intracranial hemorrhage rather than ischemic stroke. Safety results for clomethiazole compared with placebo in this group are reported. METHODS: The study included patients with a clinical diagnosis of acute hemispheric cerebral infarction. Treatment was a 24-hour intravenous infusion of 75 mg/kg clomethiazole or placebo. Patients with intracranial hemorrhage discovered on a postrandomization CT were withdrawn from study treatment if treatment was ongoing, and all patients were followed up to 90 days. RESULTS: Ninety-four patients received treatment, 47 in each group. The hemorrhage was classified as intracerebral in 89 patients (94%). Mortality at 90 days was 19.1% in the clomethiazole group and 23.4% in the placebo group. Sedation was the most common adverse event, occurring at a higher incidence in clomethiazole-treated patients (clomethiazole 53%, placebo 17%), followed by rhinitis and coughing. The incidence and pattern of serious adverse events was similar between the treatment groups. The percentage of patients reaching relative functional independence on the Barthel Index (score >/=60) at 90 days was 59.6% in the clomethiazole group and 53.2% in the placebo group. CONCLUSIONS: Clomethiazole appears safe to administer to hemorrhagic stroke patients compared with placebo. These results would obviate the need for a CT scan before therapy is initiated in acute stroke. The safety of clomethiazole in hemorrhagic stroke patients will be further evaluated in a prospective study that is under way in North America.

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The Clomethiazole Acute Stroke Study (CLASS) showed no difference in outcome between patients treated with clomethiazole or placebo for all patients treated, but a beneficial effect in patients classified as a total anterior circulation syndrome (TACS). These are patients with clinical symptoms of a large stroke. Safety and tolerability data are reported here with emphasis on the safety of treating stroke patients with a sedative drug. In total, 1,356 patients were eligible for safety analysis. Mortality at 90 days was equal between the treatment groups (clomethiazole, 19.5%; placebo, 19.7%). Clomethiazole was generally well-tolerated. The most common adverse event was sedation (clomethiazole, 53%; placebo, 10%). Clomethiazole also produced some respiratory adverse events (e.g., rhinitis and increased sputum). Serious adverse events associated with sedation were more commonly reported in the clomethiazole group during treatment. However, the incidence was low. There was no difference in the incidence of serious adverse events between the treatment groups for pulmonary conditions, cardiovascular conditions, or other conditions. Clomethiazole produced a small decrease in blood pressure, but this was not associated with a worse outcome. Safety and tolerability in TACS patients was similar to that for all patients treated with the exception that these patients were more sensitive to the sedative effects of the drug. Despite this, mortality was slightly lower, and functional outcome was better in clomethiazole-treated TACS patients compared with placebo. In conclusion, clomethiazole was generally well-tolerated. The sedation observed did not increase the risk for complications, such as pulmonary serious adverse events or affect the outcome in a negative way. Clomethiazole appeared to be safe to use in stroke patients in general and in patients with a large stroke. The efficacy and safety in large strokes will be studied further in a new study, which is ongoing.

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BACKGROUND AND PURPOSE: The efficacy and safety of the neuroprotective drug clomethiazole was tested in a double blind placebo controlled trial in patients with a clinical diagnosis of acute hemispheric stroke. METHODS: Patients with symptom onset of /=60 points on the Barthel Index) at 90 days. RESULTS: A total of 1360 patients were included. In the main efficacy analysis (n=1353), 56.1% of patients taking clomethiazole and 54.8% of placebo patients reached relative functional independence. The difference was not statistically significant. An analysis of the effect of time since onset of symptoms showed no difference between the treatment groups. Clomethiazole was generally well tolerated and appeared safe in the population studied. Sedation was the most common adverse event, leading to treatment withdrawal that occurred in 15.6% of clomethiazole-treated patients compared with 4.2% of placebo-treated patients. In a subgroup classified before randomization as having total anterior circulation syndrome (TACS) (n=545, or 40% of all randomized patients), the percentage of those reaching relative functional independence was 40.8% on clomethiazole and 29.8% on placebo, a difference of approximately 11 percentage units. TACS patients have clinical symptoms suggesting a "large" stroke. CONCLUSIONS: Clomethiazole had no adverse or beneficial effect on long-term outcome for all patients but produced sedation. The hypothesis that clomethiazole is effective in patients with large strokes will be tested in a further study.

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The CLASS study showed no significant difference between treatment groups for the neuroprotectant clomethiazole compared with placebo. However, a beneficial effect of the drug was seen in patients with total anterior circulation syndrome (TACS). These are patients with clinical symptoms suggesting a large stroke. Full results of this subgroup analysis are reported. Patients were classified before randomization using clinical symptoms into the stroke syndromes TACS, partial anterior circulation syndrome, and lacunar syndrome. Subgroup analyses of stroke syndromes were performed post hoc after detecting a treatment by severity interaction. The primary efficacy variable was relative functional independence defined as the proportion of patients scoring > or =60 on the Barthel Index at 90 days. TACS patients (n=546, 40% of all CLASS patients) were more severe at baseline on the 58 point Scandinavian Stroke Scale compared with non-TACS patients (median difference 10 points, mean difference 10.9 points, SE=0.6). Outcome for TACS patients treated with placebo was poor, with only 29.8% reaching relative functional independence. This was increased to 40.8% in the clomethiazole group, a 37% relative benefit, which is clinically significant (odds ratio=1.62, 95% CI 1.13-2.31, nominal P=.008). There was little or no difference in the outcome of non-TACS patients treated with clomethiazole compared with placebo. The treatment effect in TACS patients was quite consistent across participating countries and the 3 parts of the study defined by the 2 interim analyses. The treatment effect seen in patients with clinical symptoms suggesting a large stroke (TACS) is biologically plausible but requires confirmation in a prospective study which is ongoing.

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Clomethiazole is a drug with sedative properties effective in laboratory studies of brain ischemia. A large European multicenter trial of clomethiazole in acute stroke patients showed no benefit overall, but subgroup analysis indicated that patients with large infarctions may have benefited from treatment. To confirm this preliminary finding, we have designed CLASS-IHT, the Clomethiazole for Acute Stroke Study in Ischemic, Hemorrhagic and TPA Treated Patients, to be conducted in North America. Patients who suffer large cerebral infarctions and present within 12 hours of symptom onset are eligible. Patients will be randomized to receive clomethiazole 68 mg/kg over 24 hours or vehicle, using a dosing scheme based on the pharmacokinetics measured in the first trial. Outcome assessments include stroke scales, the Barthel Index, and lesion volume. An additional study of health economic outcomes is planned. The primary endpoint for CLASS-I will be the Barthel Index 90 days after stroke. A total of 1,200 patients will be randomized to CLASS-I, and in safety-only trials, 200 patients with cerebral hemorrhage will be randomized into CLASS-H and another 100 to 200 patients will be randomized into CLASS-T. The details of the protocols for all three studies are presented.

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An open non-comparative multicentre study was carried out to evaluate the safety and tolerability of remoxipride over a treatment period of 12 months. The efficacy of the drug in controlling psychotic symptoms was also monitored. Eighty-five men and women aged 18-69 who met the Research Diagnostic Criteria for schizophrenia were entered into the study and after withdrawal of previous antipsychotic medication, treated orally with remoxipride 75-300 mg b.i.d. The treatment was well tolerated and most of the adverse symptoms reported were reduced in incidence at the last rating compared to baseline. Sleep problems (insomnia and increased sleep) and increased thirst showed an increase in incidence during treatment. The incidence of extrapyramidal side effects was low and less than at baseline; there was no evidence that remoxipride produced an increase in abnormal involuntary movements, the median weight of the group did not alter and remoxipride produced no significant effect on cardiovascular, clinical chemistry and haematology variables. It appeared effective in controlling psychotic symptoms and produced some improvement on over one third of the patients despite the fact that the majority of patients entered were not in a productive phase of their illness. The results indicate that remoxipride will be well tolerated and effective when given for the maintenance treatment of schizophrenia.

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Nine elderly parkinsonian volunteers took single doses of 384 mg of chlormethiazole, 10 mg of temazepam and placebo capsules in a double-blind three-way cross-over study on separate visits at least one week apart. In the 6 hours following the dose, the level of drowsiness, performance on a series of psychomotor tests, effects on parkinsonian symptoms and signs, and standing and lying blood pressure were recorded. Chlormethiazole produced drowsiness on all tests and impaired psychomotor performance, as compared with placebo, without affecting parkinsonian symptoms and signs, or postural blood pressure. Temazepam was consistently less potent than chlormethiazole on tests of drowsiness and psychomotor performance. Both treatments were well tolerated. It is suggested that chlormethiazole is safe to use as a hypnotic at this dosage in this group of patients with Parkinson's disease, while temazepam did not appear to be effective as a hypnotic at this dosage.

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Twenty-four stable, chronic schizophrenic inpatients were entered in a double-blind crossover study designed to compare single dose and steady state pharmacokinetic profiles of an immediate release formulation (IR) 200 mg BID and a controlled release formulation (CR) of remoxipride 400 mg once daily. The rate of absorption of remoxipride CR was significantly lower than the IR formulation and tmax was prolonged from 1.3 to 7.9 h after a single dose and from 2.2 to 6.0 h after repeated dosing. Although the single dose of remoxipride CR was twice as large as the single dose of the IR, the Cmax was similar for both formulations after a single dose. However, the Cmax at steady state was slightly lower for CR. There was significantly less fluctuation in plasma concentrations at steady state with the CR formulation, although the average plasma concentration of remoxipride IR and CR was similar. The mean relative bioavailability with regard to the amount of remoxipride absorbed after remoxipride CR 400 mg once daily compared to IR 200 mg BID was 97%. It was concluded that the CR formulation is suitable for a once-daily administration from a pharmacokinetic point of view.

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Twenty-four stable, chronic schizophrenic inpatients were entered in a double-blind, crossover study designed to compare single-dose and steady-state pharmacokinetics of remoxipride immediate release (IR) 200 mg twice daily and controlled release (CR) 400 mg once daily. The CR formulation showed a significantly delayed absorption of remoxipride from the gastrointestinal tract. At steady state there was significantly less fluctuation in plasma concentrations. The other pharmacokinetic variables studied showed no difference. The mean relative bioavailability with regard to the amount of remoxipride absorbed after administration in CR form as compared with the IR form was 97%. Both formulations were well tolerated and there was no difference in either the incidence or the severity of adverse events. It was concluded that, from a pharmacokinetic point of view, the CR formulation of remoxipride was suitable for a once daily dosage schedule.

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1 The possible involvement of N-methyl-D-aspartate (NMDA)-receptors in epileptiform synaptic activity in the kainic acid (KA) lesioned hippocampus was investigated. In this chronic model of epilepsy there is a loss of both the early and the late components of synaptic inhibition as well as changes in the membrane properties of the surviving CA1 pyramidal cells. 2 The action of the specific NMDA-receptor antagonist D-2-amino-5-phosphonovalerate (D-APV) was tested on evoked bursts of action potentials recorded intracellularly from cells of lesioned hippocampi. The effects of D-APV on control synaptic responses from the contralateral, unlesioned hippocampi were also recorded. 3 In the presence of Mg2+ (1 mM), D-APV (20 microM) had a profound effect on the evoked epileptiform activity. Both the number of action potentials in the burst, as well as the area under the excitatory postsynaptic potential (e.p.s.p.) was considerably reduced. Furthermore this D-APV-sensitive component of the epileptiform burst had a very early onset, coincident with the first action potential in the burst. 4 D-APV (20 microM) was ineffective in blocking the e.p.s.p. evoked by Schaffer collateral afferents onto CA1 cells in slices of hippocampus contralateral to the KA lesion. 5 D-APV had no effect on the passive membrane properties of either population of cells. Hyperpolarizing potentials such as the inhibitory postsynaptic potentials (i.p.s.ps) or the afterhyperpolarization following a current-induced burst of action potentials were also unaffected. 6 It appears that an NMDA-receptor component is expressed during synaptically evoked epileptiform activity in this chronic model of epilepsy.

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1. The response of CA1 pyramidal neurones to somatic application of gamma-aminobutyric acid (GABA) was studied in adult hippocampal slices using single-electrode voltage-clamp techniques. 2. Small ionophoretic applications of GABA produced a pure outward current at the cell resting potential when recording with potassium-acetate-filled microelectrodes. This response reversed at a membrane potential of -69 +/- 5 mV (mean +/- 1 S.D.; n = 20). In recordings made with caesium-chloride-filled electrodes the GABA response reversed at -24 +/- 12 mV (n = 9). 3. The effect of different holding potentials on the size of the GABA response was examined in the range of -100 to -40 mV in twenty neurones using potassium-acetate-filled electrodes. In every case outward rectification of the response was observed. For twelve neurones the mean ratio (+/- 1 S.D. of the mean) of the conductance increase produced by GABA at -55 mV compared to -85 mV was 1.9 +/- 0.5. 4. Step changes in holding potential resulted in shifts in chloride equilibrium potential (ECl), as determined by time-dependent changes in the size of GABA-induced currents. The new value of ECl was generally reached within a few seconds of altering the membrane potential. Shifts in ECl did not appear to affect the extent of rectification but would cause underestimates of conductance measurements unless these were 'instantaneous'. The mean ratio (+/- 1 S.D. of the mean) of the 'instantaneous' conductance increase produced by GABA at 13 mV positive to that at 13 mV negative to ECl was 1.8 +/- 0.3. 5. The outward rectification was greater than that predicted by the constant-field equation. Possible factors that might contribute towards the rectification and its physiological significance are discussed.

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Epileptiform bursts of population spikes were evoked in the CA1 region of slices of the hippocampus in which the CA3 region had been previously lesioned with kainic acid. D-2-amino-5-phosphonovalerate (D-APV), a specific N-methyl-D-aspartate (NMDA) antagonist, would markedly reduce the number of spikes in the burst but had no effects on the primary population spike or the amplitude of the field excitatory postsynaptic potential (EPSP). In unlesioned control slices only a single population spike was evoked and D-APV had no effect on this response or the field EPSP. Multiple population spike bursts evoked following application of bicuculline to control slices were much less attenuated by D-APV. The results suggest that activation of NMDA receptors contributes to the production of epileptiform activity in the kainic acid-lesioned hippocampus.

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Somatic and dendritic responses to gamma-aminobutyric acid (GABA) were recorded intracellularly from CA1 pyramidal cells in slices of the hippocampus ipsilateral and contralateral to a unilateral kainic acid lesion of the CA3 region. Ipsilateral CA1 cells show a loss of GABA-mediated synaptic inhibition. However, somatic GABA responses and the sensitivity of cells to GABA were very similar in ipsilateral and contralateral cells. This was also true for dendritic applications of GABA.

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Intracellular recordings were made from hippocampal CA1 pyramidal cells in slices where the CA3/CA4 region had been lesioned using intracerebroventricular kainic acid. In 55% of the cells studied orthodromic excitation evoked bursts of action potentials. This bursting activity was associated with a decrease in or loss of the early phase to the hyperpolarisation which normally follows orthodromically evoked action potentials. The recurrent inhibitory post-synaptic potential produced by antidromic activation of pyramidal cells was also reduced or absent. A late phase to the orthodromic hyperpolarisation was reduced in cells from lesioned slices. However, in normal slices treated with bicuculline this potential showed an apparent increase. The afterhyperpolarisation which follows a short current evoked burst of action potentials was reduced in bursting cells from lesioned slices. In addition, a silent period in the firing pattern produced by long depolarising current pulses was reduced or absent in these cells. These results together with observations made with bicuculline suggest that the bursting activity in lesioned slices is largely due to a loss of inhibition mediated by gamma-aminobutyric acid. It is proposed that the kainic acid-lesioned in vitro hippocampus may be a suitable preparation for studying the electrophysiology of temporal lobe epilepsy.

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