Effect of oral nimodipine on cerebral infarction and outcome after subarachnoid haemorrhage: British aneurysm nimodipine trial

OBJECTIVE

To determine the efficacy of oral nimodipine in reducing cerebral infarction and poor outcomes (death and severe disability) after subarachnoid haemorrhage.

DESIGN

Double blind, placebo controlled, randomised trial with three months of follow up and intention to treat analysis. To have an 80% chance with a significance level of 0.05 of detecting a 50% reduction in an incidence of cerebral infarction of 15% a minimum of 540 patients was required.

SETTING

Four regional neurosurgical units in the United Kingdom.

PATIENTS

In all 554 patients were recruited between June 1985 and September 1987 out of a population of 1115 patients admitted with subarachnoid haemorrhage proved by the results of lumbar puncture or computed tomography, or both. The main exclusion criterion was admission to the neurosurgical units more than 96 hours after subarachnoid haemorrhage. There were four breaks of code and no exclusions after entry. One patient was withdrawn and in 130 treatment was discontinued early. All patients were followed up for three months and were included in the analysis, except the patient who had been withdrawn.

INTERVENTIONS

Placebo or nimodipine 60 mg was given orally every four hours for 21 days to 276 and 278 patients, respectively. Treatment was started within 96 hours after subarachnoid haemorrhage.

END POINTS

Incidence of cerebral infarction and ischaemic neurological deficits and outcome three months after entry.

MEASUREMENTS

Demographic and clinical data, including age, sex, history of hypertension and subarachnoid haemorrhage, severity of haemorrhage according to an adaptation of the Glasgow coma scale, number and site of aneurysms on angiography, and initial findings on computed tomography were measured at entry. Deterioration, defined as development of a focal sign or fall of more than one point on the Glasgow coma scale for more than six hours, was investigated by using clinical criteria and by computed tomography, by lumbar puncture, or at necropsy when appropriate. All episodes of deterioration and all patients with a three month outcome other than a good recovery were assessed by a review committee.

MAIN RESULTS

Demographic and clinical data at entry were similar in the two groups. In patients given nimodipine the incidence of cerebral infarction was 22% (61/278) compared with 33% (92/276) in those given placebo, a significant reduction of 34% (95% confidence interval 13 to 50%). Poor outcomes were also significantly reduced by 40% (95% confidence interval 20 to 55%) with nimodipine (20% (55/278) in patients given nimodipine v 33% (91/278) in those given placebo).

CONCLUSIONS

Oral nimodipine 60 mg four hourly is well tolerated and reduces cerebral infarction snd improves outcome after subarachnoid haemorrhage.

Preparation and drug release behaviors of nimodipine-loaded poly(caprolactone)-poly(ethylene oxide)-polylactide amphiphilic copolymer nanoparticles

Amphiphilic block copolymers, poly(caprolactone)-poly(ethylene glycol)-poly(lactide) (PCELA), were synthesized by ring opening polymerization of caprolactone and lactide initiated with the hydroxyl groups of poly(ethylene glycol) (PEG). These copolymers could form micelle-like nanoparticles due to their amphiphilic characteristic. From the observation of transmission electron microscopy (TEM), the nanoparticles exhibited a regular spherical shape with core-shell structure. The critical micelle concentrations (CMC) of these nanoparticles in water were decreased as molecular weight of PEG decreased. The particle sizes obtained by dynamic light scattering of these nanoparticles were in the range of 100-200 nm, and increased as the hydrophobic property of the nanoparticles increased. Nimodipine as a model drug was loaded in these nanoparticles to investigate the drug release behavior. It was found that the chemical composition of the nanoparticles was a key factor in controlling nanoparticle size, nanoparticle yields, drug-entrapment efficiency, and drug release behavior. When the PEG content is about 2% (wt), the release profile of PCELA nanoparticles appeared to follow zero-order kinetics.

A randomized, double-blind, vehicle-controlled trial of tirilazad mesylate in patients with aneurysmal subarachnoid hemorrhage: a cooperative study in North America

To test the safety and efficacy of tirilazad mesylate, a nonglucocorticoid 21-aminosteroid, in improving the outcome of patients with aneurysmal subarachnoid hemorrhage (SAH), 902 patients were enrolled in a prospective randomized, double-blind, vehicle-controlled trial at 54 North American neurosurgical centers. Five patients were excluded prior to receiving any study drug. Of 897 patients who received at least one dose of study medication, 300 received a placebo containing a citrate vehicle, 298 received 2 mg/kg per day tirilazad, and 299 received 6 mg/kg per day tirilazad, all administered intravenously beginning within 48 hours of the SAH and continuing through 10 days posthemorrhage. All patients were also treated with orally administered nimodipine. At 3 months post-SAH, there were no significant differences (p < 0.025) among the groups with regard to mortality rate, favorable outcome on the Glasgow Outcome Scale, or employment status. During the first 14 days after the SAH, there were no significant differences among the groups in the incidence or severity of clinically symptomatic or angiographically identifiable cerebral vasospasm. Mortality data stratified by gender and neurological grade on admission (assessed according to a modified World Federation of Neurological Surgeons scale) demonstrated that the men with Grades IV to V had a 33% mortality rate in the vehicle group, 52% in the 2 mg/kg per day tirilazad group (p = 0.29), and 5% in the 6 mg/kg per day tirilazad group (p = 0.03). Tirilazad was well tolerated at both dose levels. Tirilazad mesylate at dosage levels of up to 6 mg/kg per day for 8 to 10 days following SAH did not improve the overall outcome in patients with aneurysmal SAH in this trial. The differences in the efficacy of tirilazad in this trial and a previously reported trial in Europe, Australia, and New Zealand, in which dosage levels of tirilazad of 6 mg/kg per day reduced mortality rates and increased good recovery, may be a result of differences in admission characteristics of the patients and/or differences in management protocols, including the use of anticonvulsant medications.

Preparation of nimodipine-loaded microemulsion for intranasal delivery and evaluation on the targeting efficiency to the brain

The purpose of this study was to improve the solubility and enhance the brain uptake of nimodipine (NM) in an o/w microemulsion, which was suitable for intranasal delivery. Three microemulsion systems stabilized by the nonionic surfactants either Cremophor RH 40 or Labrasol, and containing a variety of oils, namely isopropyl myristate, Labrafil M 1944CS and Maisine 35-1 were developed and characterized. The nasal absorption of NM from microemulsion formulation was investigated in rats. The optimal microemulsion formulation consisted of 8% Labrafil M 1944CS, 30% Cremophor RH 40/ethanol (3:1) and water, with a maximum solubility of NM up to 6.4 mg/ml, droplet size of 30.3 +/- 5.3 nm, and no ciliotoxicity. After a single intranasal administration of this preparation at a dose of 2 mg/kg, the plasma concentration peaked at 1 h and the absolute bioavailability was about 32%. The uptake of NM in the olfactory bulb from the nasal route was three folds, compared with intravenous (i.v.) injection. The ratios of AUC in brain tissues and cerebrospinal fluid to that in plasma obtained after nasal administration were significantly higher than those after i.v. administration. These results suggest that the microemulsion system is a promising approach for intranasal delivery of NM for the treatment and prevention of neurodegenerative diseases.

Effect of intravenous nimodipine on blood pressure and outcome after acute stroke

BACKGROUND AND PURPOSE

The Intravenous Nimodipine West European Stroke Trial (INWEST) found a correlation between nimodipine-induced reduction in blood pressure (BP) and an unfavorable outcome in acute stroke. We sought to confirm this correlation with and without adjustment for prognostic variables and to investigate outcome in subgroups with increasing levels of BP reduction.

METHODS

Patients with a clinical diagnosis of ischemic stroke (within 24 hours) were consecutively allocated to receive placebo (n=100), 1 mg/h (low-dose) nimodipine (n=101), or 2 mg/h (high-dose) nimodipine (n=94). The correlation between average BP change during the first 2 days and the outcome at day 21 was analyzed.

RESULTS

Two hundred sixty-five patients were included in this analysis (n=92, 93, and 80 for placebo, low dose, and high dose, respectively). Nimodipine treatment resulted in a statistically significant reduction in systolic BP (SBP) and diastolic BP (DBP) from baseline compared with placebo during the first few days. In multivariate analysis, a significant correlation between DBP reduction and worsening of the neurological score was found for the high-dose group (beta=0.49, P=0. 048). Patients with a DBP reduction of > or =20% in the high-dose group had a significantly increased adjusted OR for the compound outcome variable death or dependency (Barthel Index <60) (n/N=25/26, OR 10. 16, 95% CI 1.02 to 101.74) and death alone (n/N=9/26, OR 4.336, 95% CI 1.131 16.619) compared with all placebo patients (n/N=62/92 and 14/92, respectively). There was no correlation between SBP change and outcome.

CONCLUSIONS

DBP, but not SBP, reduction was associated with neurological worsening after the intravenous administration of high-dose nimodipine after acute stroke. For low-dose nimodipine, the results were not conclusive. These results do not confirm or exclude a neuroprotective property of nimodipine.

Preparation, characterization, and drug release behaviors of drug nimodipine-loaded poly(epsilon-caprolactone)-poly(ethylene oxide)-poly(epsilon-caprolactone) amphiphilic triblock copolymer micelles

Amphiphilic triblock copolymers, poly(epsilon-caprolactone)-poly(ethylene oxide)-poly(epsilon-caprolactone) (PCL-PEO-PCL), were synthesized by ring opening polymerization of epsilon-caprolactone initiated with the hydroxyl functional groups of poly(ethylene glycol) at both ends of the chain. The micelles composed of this type of copolymer had such a structure that both ends of the PEO chain were anchored to the micelle. The critical micelle concentration of the block copolymer in distilled water was determined by a fluorescence probe technique using pyrene. As the hydrophobic components of the block copolymer increased, the critical micelle concentration value decreased. To estimate the feasibility as novel drug carriers, the block copolymer micelles were prepared by precipitation of polymer from acetone solution into water. From the observation of transmission electron microscopy, the micelles exhibited a spherical shape. Nimodipine was incorporated into the hydrophobic inner core of micelles as a lipophilic model drug to investigate the drug release behavior. The PEO/PCL ratio of copolymer was a main factor in controlling micelle size, drug-loading content, and drug release behavior. As PCL weight ratio increased, the micelle size and drug-loading content increased, and the drug release rate decreased.

Steroids for acute spinal cord injury

BACKGROUND

Acute spinal cord injury is a devastating condition typically affecting young people, mostly males. Steroid treatment in the early hours after the injury is aimed at reducing the extent of permanent paralysis during the rest of the patient's life.

OBJECTIVES

To review randomized trials of steroids for human acute spinal cord injury.

SEARCH METHODS

We searched the Cochrane Injuries Group Specialised Register (searched 02 Aug 2011), The Cochrane Central Register of Controlled Trials 2011, issue 3 (The Cochrane Library), MEDLINE (Ovid) 1948 to July Week 3 2011, EMBASE (Ovid) 1974 to 2011 week 17, ISI Web of Science: Science Citation Index Expanded (SCI-EXPANDED) 1970 to Aug 2011, ISI Web of Science: Conference Proceedings Citation Index- Science (CPCI-S) 1990 to Aug 2011 and PubMed [www.ncbi.nlm.nih.gov/sites/entrez/] (searched 04 Aug 2011) for records added to PubMed in the last 90 days). Files of the National Acute Spinal Cord Injury Study (NASCIS) were reviewed (NASCIS was founded in 1977 and has tracked trials in this area since that date). We also searched the reference lists of relevant studies and previously published reviews.

SELECTION CRITERIA

All randomized controlled trials of steroid treatment for acute spinal cord injury in any language.

DATA COLLECTION AND ANALYSIS

One review author extracted data from trial reports. Japanese and French studies were found through NASCIS and additional data (e.g. SDs) were obtained from the original study authors.

MAIN RESULTS

Eight trials are included in this review, seven used methylprednisolone. Methylprednisolone sodium succinate has been shown to improve neurologic outcome up to one year post-injury if administered within eight hours of injury and in a dose regimen of: bolus 30mg/kg over 15 minutes, with maintenance infusion of 5.4 mg/kg per hour infused for 23 hours. The initial North American trial results were replicated in a Japanese trial but not in the one from France. Data was obtained from the latter studies to permit appropriate meta-analysis of all three trials. This indicated significant recovery in motor function after methylprednisolone therapy, when administration commenced within eight hours of injury. A more recent trial indicates that, if methylprednisolone therapy is given for an additional 24 hours (a total of 48 hours), additional improvement in motor neurologic function and functional status are observed. This is particularly observed if treatment cannot be started until between three to eight hours after injury. The same methylprednisolone therapy has been found effective in whiplash injuries. A modified regimen was found to improve recovery after surgery for lumbar disc disease. The risk of bias was low in the largest methyprednisolne trials. Overall, there was no evidence of significantly increased complications or mortality from the 23 or 48 hour therapy.

AUTHORS' CONCLUSIONS

High-dose methylprednisolone steroid therapy is the only pharmacologic therapy shown to have efficacy in a phase three randomized trial when administered within eight hours of injury. One trial indicates additional benefit by extending the maintenance dose from 24 to 48 hours, if start of treatment must be delayed to between three and eight hours after injury. There is an urgent need for more randomized trials of pharmacologic therapy for acute spinal cord injury.

Complement activation in the central nervous system following blood-brain barrier damage in man

The central nervous system (CNS) is virtually isolated from circulating immunological factors such as complement (C), an important mediator of humoral immunity and inflammation. In circulation, C is constantly inhibited to prevent attack on host cells. Since a host of diseases produce an abnormal blood-brain/cerebrospinal fluid (blood-brain/CSF) permeability allowing C protein extravasation, we investigated if C activation occurs in CSF in vitro and in CNS in vivo during subarachnoid hemorrhage (SAH) or brain infarction. After SAH (n = 15), the terminal complement complex (TCC) concentration on days 0 to 2 was higher in the CSF, 210 +/- 61 ng/ml, than in the plasma, 63 +/- 17 ng/ml, but null in the CSF of controls (n = 8) or patients with an ischemic stroke (n = 7). TCC was eliminated from the CSF after SAH (24 +/- 10 ng/ml on days 7 to 10). Incubation of normal human CSF with serum in vitro also activated the terminal C pathway. In 10 fatal ischemic brain infarctions, immunohistochemical techniques demonstrated neuronal fragment-associated deposition of C9 accompanied by neutrophil infiltration. We conclude that the C system becomes activated intrathecally in SAH and focally in the brain parenchyma in ischemic stroke. By promoting chemotaxis and vascular perturbation, C activation may instigate nonimmune inflammation and aggravate CNS damage in diseases associated with plasma extravasation.

Intravenous magnesium versus nimodipine in the treatment of patients with aneurysmal subarachnoid hemorrhage: a randomized study

OBJECTIVE

The prophylactic use of nimodipine in patients with aneurysmal subarachnoid hemorrhage reduces the risk of ischemic brain damage. However, its efficacy seems to be rather moderate. The question arises whether other types of calcium antagonists offer better protection. Magnesium, nature's physiological calcium antagonist, is neuroprotective in animal models, promotes dilatation of cerebral arteries, and has an established safety profile. The aim of the current pilot study is to evaluate the efficacy of magnesium versus nimodipine to prevent delayed ischemic deficits after aneurysmal subarachnoid hemorrhage.

METHODS

One hundred and thirteen patients with aneurysmal subarachnoid hemorrhage were enrolled in the study and were randomized to receive either magnesium sulfate (loading 10 mg/kg followed by 30 mg/kg daily) or nimodipine (48 mg/d) intravenously until at least postoperative Day 7. Primary outcome parameters were incidence of clinical vasospasm and infarction. Secondary outcome measures were the incidence of transcranial Doppler/angiographic vasospasm, the neuronal markers (neuron-specific enolase, S-100), and the patients' Glasgow Outcome Scale scores at discharge and after 1 year.

RESULTS

One hundred and four patients met the study requirements. In the magnesium group (n = 53), eight patients (15%) experienced clinical vasospasm and 20 (38%) experienced transcranial Doppler/angiographic vasospasm compared with 14 (27%) and 17 (33%) patients in the nimodipine group (n = 51). If clinical vasospasm occurred, 75% of the magnesium-treated versus 50% of the nimodipine-treated patients experienced cerebral infarction resulting in fatal outcome in 37 and 14%, respectively. Overall, the rate of infarction attributable to vasospasm was virtually the same (19 versus 22%). There was no difference in outcome between groups.

CONCLUSION

The efficacy of magnesium in preventing delayed ischemic neurological deficits in patients with aneurysmal subarachnoid hemorrhage seems to be comparable with that of nimodipine. The difference in their pharmacological properties makes studies on the combined administration of magnesium and nimodipine seem promising.

Nimodipine for treatment of primary thunderclap headache

Eleven patients with primary thunderclap headache (TCH) were treated with oral nimodipine 30 to 60 mg every 4 hours or IV nimodipine 0.5 to 2 mg/h if the oral regimen failed or images showed cerebral vasospasm. With oral nimodipine, headache did not recur in the nine patients without vasospasm. IV nimodipine was given in two patients with vasospasm, including one who developed ischemic stroke. Nimodipine may be effective for TCH. Vasospasm may warrant IV nimodipine.

Effects of dihydropyridine calcium channel antagonists in ethanol withdrawal; doses required, stereospecificity and actions of Bay K 8644

The effects of dihydropyridine calcium channel antagonists, and the calcium channel activator, Bay K 8644, were examined on the convulsive behaviour induced by handling in mice following withdrawal from chronic ethanol inhalation. Nimodipine and nitrendipine and PN 200-110 significantly decreased the convulsive behaviour, after intraperitoneal doses of the same order of magnitude as have been found by others to be required for displacement of radiolabelled dihydropyridine in the CNS. The (+) isomer of PN 200-110 was effective, but the (-) isomer, which is ineffective in vitro, had no significant action. Bay K 8644 prevented the actions of nimodipine against the ethanol withdrawal syndrome. The behavioural ratings after nimodipine plus Bay K 8644 were significantly higher than after vehicle treatment. Bay K 8644 alone, when given to naive mice, caused convulsive behaviour resembling that seen in withdrawal from chronic ethanol treatment, but when given during ethanol withdrawal did not significantly increase the behavioural signs.

Clinical significance of the finding of subarachnoid blood on CT scan after head injury

The population analysed consisted of 268 out of 819 patients of a European nimodipine multicentre trial on severe head injury, whose first CT scan after injury showed signs of subarachnoid bleeding. The study demonstrated the importance of traumatic subarachnoid haemorrhage (tSAH) per se as a prognostic factor. The outcome of patients with tSAH is significantly worse than that of patients whose first CT does not show subarachnoid blood (noSAH). The outcome was unfavourable (dead, persistent vegetative state, severe disability) in 60% of tSAH patients compared to 30% of noSAH patients (p < 0.001). The difference in mortality was 42% vs. 14% (p < 0.001). The six month follow-up of tSAH patients complying with the study protocol and treated with intravenous nimodipine, 2 mg per hour for 7 days, showed a statistically significant reduction of unfavourable outcome from 66% to 51% (p < 0.05), compared to placebo treated patients.

Causes of morbidity and mortality after ruptured aneurysm surgery in a series of 230 patients. The importance of control angiography

BACKGROUND AND PURPOSE

The purpose of this study was to determine the causes of morbidity and mortality after surgery for ruptured aneurysms.

METHODS

Two hundred thirty consecutive patients were studied. Initial hemorrhage volume and vasospasm were evaluated preoperatively with CT, transcranial Doppler ultrasonography, and angiography. Nimodipine infusion was started before surgery. Preoperative clinical status was evaluated according to Hunt and Hess grading criteria. Surgery was performed early in 186 patients (81%). Control angiography, transcranial Doppler ultrasonography, and CT were performed routinely after surgery. Hypodense areas revealed by control CT were related to intracerebral initial hematoma, vasospasm, postoperative thrombosis, or spatula hyperpressure.

RESULTS

Clinical outcome was excellent or good (Glasgow Outcome Scale [GOS] scores of 1 or 2) in 176 patients (77%), 17 (7%) were disabled (GOS score of 3), and 37 (16%) were vegetative or dead. In patients in good condition (grades I to III) preoperatively (n = 200), 38 had an unfavorable outcome (GOS score of 2, 3, 4, or 5). The major cause of complication was postoperative thrombosis (42%). In patients in poor condition (grade IV or V) (n = 30), 27 had an unfavorable outcome. The major cause of complication was initial bleeding (66%). Vasospasm was responsible for delayed ischemic deficit in 9 patients (3.9% of the total population).

CONCLUSIONS

Systematic angiography remains by far the best means for determining the cause of a poor postoperative course.

Very Early Nimodipine Use in Stroke (VENUS): a randomized, double-blind, placebo-controlled trial

BACKGROUND AND PURPOSE

The Very Early Nimodipine Use in Stroke (VENUS) trial was designed to test the hypothesis that early treatment with nimodipine has a positive effect on survival and functional outcome after stroke. This was suggested in a previous meta-analysis on the use of nimodipine in stroke. However, in a recent Cochrane review we were unable to reproduce these positive results. This led to the early termination of VENUS after an interim analysis.

METHODS

In this randomized, double-blind, placebo-controlled trial, treatment was started by general practitioners or neurologists within 6 hours after stroke onset (oral nimodipine 30 mg QID or identical placebo, for 10 days). Main analyses included comparisons of the primary end point (poor outcome, defined as death or dependency after 3 months) and secondary end points (neurological status and blood pressure 24 hours after inclusion, mortality after 10 days, and adverse events) between treatment groups. Subgroup analyses (on final diagnosis and based on the per-protocol data set) were performed.

RESULTS

At trial termination, after inclusion of 454 patients (225 nimodipine, 229 placebo), no effect of nimodipine was found. After 3 months of follow-up, 32% (n=71) of patients in the nimodipine group had a poor outcome compared with 27% (n=62) in the placebo group (relative risk, 1.2; 95% CI, 0.9 to 1.6). A treatment effect was not found for secondary outcomes and in the subgroup analyses.

CONCLUSIONS

The results of VENUS do not support the hypothesis of a beneficial effect of early nimodipine in stroke patients.

Intra-arterial nimodipine for severe cerebral vasospasm after aneurysmal subarachnoid hemorrhage: influence on clinical course and cerebral perfusion

BACKGROUND AND PURPOSE

The efficacy of intra-arterial administration of nimodipine (IAN) in patients with severe vasospasm after aneurysmal subarachnoid hemorrhage (SAH) remains unproved. The goal of the present study was to investigate the clinical effect and cerebral perfusion after IAN in patients with severe vasospasm refractory to hemodynamic treatment.

MATERIALS AND METHODS

Twenty-six of 214 patients with aneurysmal SAH were included in the prospective study, approved by the local ethics committee. All patients met the criteria of medically refractory cerebral vasospasm. Effectiveness was monitored angiographically by digital subtraction angiography and by transcranial Doppler (TCD), perfusion CT (PCT), and neurologic examination during treatment course and follow-up.

RESULTS

No angiographic effect was observed in 8 patients. The pooled PCT values revealed a reduction of time to peak (P = .03) and mean transit time (P = .17) 1 day after intervention. This effect did not persist during the following days. The pooled TCD analysis demonstrated a transient increase in flow 1 day after intervention (P = .03). No trend was evident during the next 7 days after intervention. Additional infarction was experienced by 61.1% of patients.

CONCLUSIONS

IAN in a selective patient group resulted in a positive response with reduction of angiographic vasospasm and increase in cerebral perfusion as detected by PCT after 24 hours. Therefore, IAN appears more effective than intra-arterial papaverine. Nevertheless the efficacy of IAN is temporary. Therefore, the search for more effective treatment strategies to reduce critical vasospasm and to improve cerebral perfusion must be continued.

Evaluation of modified gum karaya as carrier for the dissolution enhancement of poorly water-soluble drug nimodipine

Modified gum karaya (MGK), a recently developed excipient was evaluated as carrier for dissolution enhancement of poorly soluble drug, nimodipine (NM). The advantages of MGK over the parent gum karaya (GK) were illustrated by differences in the in vitro dissolution profiles of respective solid mixtures prepared by co-grinding technique. The influence of process variable, such as polysaccharide concentration and method of preparation of solid mixture on dissolution rate was studied. Solubility studies were also performed to explain the differences in dissolution rate. Solid mixtures were characterized by differential scanning calorimetry (DSC), X-ray diffraction studies (XRD) and scanning electron microscopy (SEM). The dissolution rate of NM was increased as the MGK concentration increased and optimum ratio was found to be 1:9 w/w ratio (NM:MGK). It is found that method of preparation of solid mixtures was significantly effected the dissolution rate of NM from solid mixtures. The order of method of preparation in according to their Dissolution Efficiency is physical mixture < co-grinding mixture < swollen carrier mixture < kneading mixture (water as kneading agent) < kneading mixture (70% v/v ethanol as kneading agent) < solid dispersion. Though, the solid mixtures prepared by other methods like solid dispersion, swollen carrier mixture and kneading technique gave faster release, co-grinding mixture prepared in 1:9 w/w ratio (NM:MGK) was found to exhibit a significant improvement in dissolution rate without requiring addition of organic solvents or high temperatures for its preparation and the process is less cumbersome. Hence, co-grinding technique appears to be more easier and the most convenient method from a practical point of view.

The effect of nimodipine on the evolution of human cerebral infarction studied by PET

Fourteen patients were studied by positron emission tomography (PET) within 48 h of onset of a hemispheric ischemic stroke and again 7 days later. After the first set of PET scans, the patients were randomized to receive either nimodipine (n = 7) or a carrier solution (n = 7) by intravenous infusion. The infusions were maintained until the end of the second PET studies. CBF, cerebral blood volume (CBV), oxygen extraction ratio (OER), CMRO2, and CMRglc were measured each time. These metabolic and perfusion measurements were performed by standard methods. A surface map of each metabolic and perfusion measurement in the cortical mantle was generated by interpolating between the available slices. The various surface maps representing the physiological characteristics determined in the same or subsequent studies were aligned so that all data sets could be analyzed identically using an array of square regions of interest (ROIs). The functional status of each ROI was recorded at the two intervals following the cerebrovascular accident to characterize the evolution of the infarct, penumbra, and normal brain regions. We presumed the ischemic penumbra to be cortical regions in the proximity of the infarct and perfused at CBF values between 12 and 18 ml/100 g/min on the first PET scan, while densely ischemic regions had CBF of less than 12 nl/100 g/min and normally perfused brain greater than 18 ml/100 g/min. In the densely ischemic zone, CBF increased more in the nimodipine-treated group than in the carrier group. As well, in this region nimodipine reversed the decline in CMRO2 noted in the carrier group, the difference in the changes being significant. In the penumbra zone, comparable trends were noted in OER and CMRO2 but the difference in the changes between the two groups did not reach statistical significance. Changes in CMRglc and CBV were comparable between the two groups in both cortical regions.

A phase I/II trial of nimodipine for HIV-related neurologic complications

BACKGROUND

Few effective treatments are available for AIDS dementia complex (ADC) and HIV-associated neuropathy. However, recent in vitro studies indicate that nimodipine, a voltage-dependent calcium channel antagonist, can prevent HIV-related neuronal injury and may provide a novel form of treatment for these disorders.

METHODS

To determine the safety and possible efficacy of this agent, 41 patients with mild to severe ADC, including 19 patients with neuropathy, were entered into the AIDS Clinical Trial Group multicenter, phase-I and phase-II study. Nimodipine at 60 mg p.o., five times daily; 30 mg p.o., three times daily; or placebo was administered for 16 weeks as adjuvant treatment to antiretroviral therapy.

RESULTS

Neuropsychological performance at baseline, measured by the composite neuropsychological Z score (NPZ-8), correlated significantly with the ADC stage and with CSF levels of neopterin, a marker of immune activation. No significant differences in toxicity were observed among the three arms. Intent-to-treat analysis showed no significant change in the NPZ-8, although improvement was suggested in the high-dose arm. In addition, a trend toward stabilization in peripheral neuropathy was observed in both nimodipine arms compared with placebo.

CONCLUSIONS

Nimodipine and other similar nonantiretroviral agents may provide a safe and promising avenue of treatment for neurologic disorders associated with HIV infection. The results of this study indicate that further clinical trials are warranted.

Short-term effects of the calcium channel blocker nimodipine (Bay-e-9736) in the management of primary degenerative dementia

The etiology of Alzheimer's dementia (AD) is unknown, but several neurotransmitters, e.g., acetylcholine, have been implicated. Recently, the group of calcium channel antagonists have been reviewed for their potential neuropsychiatric applications. These agents are capable of enhancing cholinergic tone, neurofilament/microtubular stabilization, and regional perfusion rates. The following is a report of a randomized, double-blind, placebo-controlled, multicenter study of 227 AD patients treated with nimodipine, a 1.4 dihydropyridine derivative and calcium channel antagonist. The subgroup receiving active drug (30 mg t.i.d.) experienced a prophylactic benefit across eight measures over 12 treatment weeks when contrasted with the disease progression seen among placebo recipients. Calcium channel blockers as neurotransmitter modulators and/or via calcium's theoretical role in neurofibrillary tangles, proteolysis, or neurofilament formation may represent a therapeutic opportunity for the AD patient.

Prediction of psychosocial recovery after head injury with cognitive tests and neurobehavioral ratings

A series of 53 patients was studied using a battery of tests and a neurobehavioral rating scale on average 4 months after closed-head injury (CHI). Social outcome was assessed 1 year after injury by interviewing a family member. The results supported the hypothesis that tests of flexibility and programming rather than tests of cognitive skills predict psychosocial recovery after CHI. Spatial Learning with Self-Set Goals and Sorting were measures of flexibility and programming. Contrary to expectation, word fluency performance was unrelated to these measures, but was associated with conventional intelligence tests, which did not predict psychosocial recovery. Cognition/Energy deficit on the Neurobehavioral Rating Scale and increased age were useful predictors of poor psychosocial outcome, whereas computed tomography findings or the Glasgow Coma Score were weakly related to the outcome indices. Evidently, cognitive flexibility and mental programming are very important psychological prerequisites of social recovery after CHI.

High initial blood pressure after acute stroke is associated with poor functional outcome

OBJECTIVE

To evaluate the relationship between high initial blood pressure and functional outcome in patients with acute stroke.

DESIGN

An observational study based on the data from the Intravenous Nimodipine West European Stroke Trial (INWEST). INWEST was a placebo-controlled randomized study terminated prematurely; subsequent analysis found a correlation between diastolic BP (DBP) reduction caused by high-dose nimodipine and unfavourable outcome. Subjects. Of the 295 patients with acute ischaemic stroke (within 24 h) recruited in the INWEST, 265 were included in this analysis [n = 92 for placebo, n = 93 for low-dose nimodipine (1-mg h(-1)) and n=80 for high-dose nimodipine (2-mg h(-1))]. Definition. Initial BP was defined as BP at the time of randomization. Normal initial BP (NIBP)=systolic BP (SBP) 120-160 and DBP 60-90 mmHg (n=126). Four alternatives were defined as high initial BP (HIBP): (1) >160/90 (n=126), (2) >170/95 (n=106), (3) >180/100 (n=63), (4) >190/105 (n=45). Main outcome measures. Combined death or dependency (DD) (Barthel index < 60) at 21 days.

RESULTS

In multiple logistic regression analyses, the odds ratio [OR] for DD at day 21 was significantly higher in patients with any definition of HIBP than with NIBP. For all patients, OR and 95% confidence intervals [CI] for 160/90 versus NIBP=3.1, 1.3-7.3, respectively; for 170/95=3.3, 1.4-8.1; for 180/100=7.0, 2.1-22.8; for 190/105=3.7, 1.1-12.4. For only placebo patients, OR and 95% CI for 160/90=4.8, 1.2-19.3; for 170/95=4.4, 1.1-17.8; for 180/100=12.7, 2.2-74.7; for 190/105=5.6, 1.1-30.0. The outcome was similar at 24 weeks but did not reach statistical significance for the placebo patients.

CONCLUSION

Patients with HIBP had a poor functional outcome after acute stroke.

Nimodipine nanocrystals for oral bioavailability improvement: role of mesenteric lymph transport in the oral absorption

PURPOSE

We had conducted a comprehensive study on preparation, characterization and pharmacokinetics of nimodipine nanocrystals for oral administration previously, and nimodipine nanocrystals displayed lower dissolution profiles but higher bioavailability than Nimotop(®). In this study, we aimed at elucidating the reasons of unfavorable in vitro in vivo correlation for NMD nanocrystals and Nimotop(®) with a hypothesis that special oral absorption mechanism was involved in the absorption of nimodipine nanocrystals.

METHODS

Investigations of oral absorption mechanism of the nanocrystals were performed on everted gut sac models, lymphatically (mesenteric lymph duct) cannulated SD rats, Caco-2 cell monolayers and chylomicron flow blocking rats, respectively.

RESULTS

The permeability of nanocrystals in duodenum, ileum and colon was not superior to that of Nimotop(®), suggestive of special absorption mechanisms involved. Exudates of nanocrystals from enterocytes were detected in mesenteric lymphatic fluids using a transmission electron microscope, and the bioavailability was only about half of the control after the mesenteric lymph was blocked. The nanocrystals were taken up by enterocytes via macropinocytosis and caveolin-mediated endocytosis pathways.

CONCLUSIONS

It was impossible to establish a favorable in vitro in vivo correlation for NMD nanocrystals and Nimotop(®), because portions of the nanocrystals underwent macropinocytosis and caveolin-mediated endocytosis by enterocytes as intact nanocrystal forms, then bypassed the liver first-pass metabolism.

A double blind, randomized clinical trial assessing the efficacy and safety of augmenting standard antidepressant therapy with nimodipine in the treatment of 'vascular depression'

BACKGROUND

'Vascular depression' may be caused by cerebrovascular disease. Calcium channel blockers, which are putative treatments for cerebrovascular disease, might be expected to improve depression reduction and to prevent recurrence of depression in this patient population. This clinical trial was designed to test these hypotheses.

DESIGN

This was a controlled, double blind, randomized clinical trial in which 84 patients with vascular depression (Alexopoulos criteria) were treated with antidepressants at standard doses. Patients were also randomized to nimodipine (n = 40) or an inactive comparator, vitamin C (n = 44). Treatment outcomes were assessed using the Hamilton depression rating scale (HDRS) regularly up to 300 days after treatment initiation.

RESULTS

As expected, depression reduction was successful in most patients. In addition, those treated with nimodipine plus an antidepressant had greater improvements in depression overall in repeated measures ANCOVA (F(1,81) = 8.64, p = 0.004). As well a greater proportion of nimodipine-treated participants (45 versus 25%) exhibited a full remission (HDRS < or = 10) (chi(2)(df, 1) = 3.71, p = 0.054). Among those experiencing a substantial response in the first 60 days (50% reduction in HDRS), fewer patients on nimodipine (7.4%) had a recurrence of major depression when compared to those on antidepressant alone (32%) (chi(2)(df, 1) = 3.59, p = 0.058).

CONCLUSIONS

In treating vascular depression, augmentation of antidepressant therapy with a calcium-channel blocker leads to greater depression reduction and lower rates of recurrence. These findings support the argument that cerebrovascular disease is involved in the pathogenesis and recurrence of depression in these patients.

Nimodipine monotherapy and carbamazepine augmentation in patients with refractory recurrent affective illness

Of 30 patients with treatment-refractory affective illness, 10 showed a moderate to marked response to blind nimodipine monotherapy compared with placebo on the Clinical Global Impressions Scale. Fourteen inadequately responsive patients (3 unipolar [UP], 11 bipolar [BP]) were treated with the blind addition of carbamazepine. Carbamazepine augmentation of nimodipine converted four (29%) of the partial responders to more robust responders. Patients who showed an excellent response to the nimodipine-carbamazepine combination included individual patients with patterns of rapid cycling, ultradian cycling, UP recurrent brief depression, and one with BP type II depression. When verapamil was blindly substituted for nimodipine, two BP patients failed to maintain improvement but responded again to nimodipine and remained well with a blind transition to another dihydropyridine L-type calcium channel blocker (CCB), isradipine. Mechanistic implications of the response to the dihydropyridine L-type CCB nimodipine alone and in combination with carbamazepine are discussed.

A double-blind, randomized clinical trial to assess the augmentation with nimodipine of antidepressant therapy in the treatment of "vascular depression"

BACKGROUND

Cerebrovascular disease may cause "vascular depression" (VaD). Calcium channel-blockers are presumed treatments for cerebrovascular disease and might be expected to improve depression and prevent recurrence.

OBJECTIVE

To examine the efficacy and tolerability of the use of nimodipine as an augmentation of fluoxetine in the treatment of VaD.

DESIGN

A double-blind, randomized clinical trial in which 101 patients with VaD (Alexopoulos criteria) were treated with fluoxetine at standard doses. Patients were randomized to placebo (n=51) or nimodipine (n=50). Treatment outcomes were assessed using the Hamilton Depression Rating Scale (HDRS) regularly up to 8 months after treatment initiation.

RESULTS

Depression was reduced in 63% of patients, but those whose treatment was enhanced with nimodipine had greater improvements overall by repeated measures analysis of covariance (ANCOVA) (F(1.80) = 9.76, p=0.001). In addition, a greater proportion of patients treated with fluoxetine-nimodipine (54% vs. 27%) exhibited full remission (chi2(d.f. 1)= 7.3, p = 0.006), with the number needed to treat (NNT) equal to 4 (95% CI 2-12). Of those experiencing full remission in the first 61 days, fewer patients on fluoxetine-nimodipine (3.7%) developed recurrence of major depression as compared to those on fluoxetine alone (35.7%) (chi2(d.f. 1) = 7.56, p = 0.006), NNT 3 (95% CI 2-9). Side-effects were noted in 33.3% of patients in the control group and 48% of the experimental group (chi2(d.f. 1) = 2.25, p = 0.133).

CONCLUSIONS

In treating VaD, augmentation of fluoxetine with nimodipine led to better treatment results and lower rates of recurrence. These findings support the argument that augmentation of antidepressant therapy might be helpful in the treatment of cerebrovascular disease, which is involved in the pathogenesis of this type of depression.