ABSTRACT
BACKGROUND AND PURPOSE: The purpose of this study was to investigate the effect of the angiotensin-converting enzyme inhibitor perindopril on mean arterial blood pressure (MABP), cerebral blood flow (CBF), and glomerular filtration rate in hypertensive stroke patients with moderate to severe internal carotid artery (ICA) disease or ICA occlusion. METHODS: Twenty-four nonacute ischemic stroke patients who had MABP readings >100 mm Hg and moderate to severe ICA stenosis or occlusion were randomized to receive perindopril 4 mg daily or placebo for 14 days. MABP, ICA flow, and both middle cerebral artery (MCA) velocity and resistance index were measured before dose, at 5 time points over the subsequent 24 hours, and finally at 2 weeks. Brain hexamethyl propylene amine oxide single photon emission computed tomography scans were performed before drug administration and at time of peak drug effect (6 to 8 hours) after the first dose. Glomerular filtration rate was measured with (51)Cr EDTA before medication and at 14 days. RESULTS: A placebo-corrected BP fall of 17/10 mm Hg was seen (P:=0.017), which was maximal at 5.5 hours. No significant change in ICA flow or MCA velocity was seen between groups. No significant change in hemispheric CBF was seen. The mean change from baseline in the treated group was -0.79 mL. 100 g(-1). min(-1) (95% confidence interval [CI], 1.65 to -3.23); mean change in the placebo group was -1.9 mL. 100 g(-1). min(-1) (95%CI, 3.02 to -6.92). Peri-infarct CBF was similarly unaffected. One of the treated patients developed transient acute renal impairment and was withdrawn from the study on day 4. CONCLUSIONS: Perindopril lowers BP without lowering CBF in hypertensive stroke patients with moderate to severe ICA stenosis or occlusion; monitoring of this patient population for the complications of renal artery stenosis should be considered.
Subject(s)
Carotid Artery Diseases/drug therapy , Cerebrovascular Circulation/drug effects , Perindopril/administration & dosage , Renal Circulation/drug effects , Stroke/drug therapy , Administration, Oral , Aged , Aged, 80 and over , Angiotensin-Converting Enzyme Inhibitors/administration & dosage , Angiotensin-Converting Enzyme Inhibitors/adverse effects , Antihypertensive Agents/administration & dosage , Antihypertensive Agents/adverse effects , Blood Flow Velocity/drug effects , Blood Pressure/drug effects , Brain/blood supply , Brain/diagnostic imaging , Brain/drug effects , Carotid Artery Diseases/complications , Carotid Artery Diseases/diagnostic imaging , Double-Blind Method , Female , Glomerular Filtration Rate/drug effects , Humans , Hypertension/complications , Hypertension/drug therapy , Male , Middle Aged , Perindopril/adverse effects , Severity of Illness Index , Stroke/complications , Stroke/diagnosis , Tomography, Emission-Computed, Single-Photon , Tomography, X-Ray Computed , Ultrasonography , Vascular Resistance/drug effectsABSTRACT
BACKGROUND AND PURPOSE: Patients with suspected stroke first assessed by ambulance paramedics require early recognition to facilitate appropriate triage and early treatment. We determined paramedic's accuracy in detecting acute stroke signs by comparing agreement between neurological signs recorded in the Face Arm Speech Test (FAST), a stroke recognition instrument, by paramedics on the scene and by stroke physicians after admission. METHODS: Suspected stroke patients admitted by ambulance paramedics directly to an acute stroke unit through a rapid ambulance protocol were examined by a trainee stroke neurologist or admitting stroke physician over a 1-year period. Recorded neurological signs (facial weakness, arm weakness, speech disturbance) in confirmed acute stroke/transient ischemic attack (TIA) cases were compared between paramedics and the stroke neurologist/physician. RESULTS: Ambulance crews referred 278 suspected stroke patients of whom 217 (78%) had confirmed stroke (n=189) or TIA (n=28); 95% were examined by the stroke neurologist (median 18 hours after paramedic assessment). Recorded signs and agreement between paramedics and stroke physicians in confirmed stroke group were: facial weakness, 68% versus 70% (kappa=0.49; 95% CI: 0.36 to 0.62); arm weakness, 96% versus 95% (kappa=0.77; 95% CI: 0.55 to 0.99); and speech disturbance, 79% versus 77% (kappa=0.69; 95% CI: 0.56 to 0.82). Interrater agreement was complete for arm weakness in 98% cases. CONCLUSIONS: Recognition of neurological deficits by ambulance paramedics using FAST shows good agreement with physician assessment, even allowing for temporal evolution of deficits. The high prevalence and good agreement for arm weakness suggest that this sign may have the greatest usefulness for prehospital ambulance triage and paramedic-based neuroprotective trials.
Subject(s)
Emergency Medical Services/methods , Stroke/diagnosis , Acute Disease , Aged , Arm , Emergency Medical Technicians , Face , Female , Humans , Male , Muscle Weakness/diagnosis , Neurologic Examination , Observer Variation , Physicians , Speech Disorders/diagnosisABSTRACT
BACKGROUND AND PURPOSE: AR-R15896AR is a use-dependent, low-affinity blocker of the NMDA ion channel with neuroprotective effects in animal models of focal cerebral ischemia. This study aimed to establish the highest safe and tolerated loading and maintenance dosing regimen of AR-R15896AR in acute ischemic stroke patients and to determine the associated plasma concentrations of AR-R15896AR. METHODS: This was a 4-part, multicenter, randomized, double-blind, placebo-controlled study in 175 patients (mean age, 69 years) within 24 hours of acute stroke symptom recognition. Ascending 60-minute intravenous infusion loading doses of AR-R15896AR were initially examined (100, 150, 200, 250, or 300 mg or placebo in 3:1 randomization, n=36 treated); in part 2, 250, 275, or 300 mg was compared with placebo (n=33). In part 3, a 250-mg loading dose was followed by 9 maintenance doses of 60, 75, 90, 105, or 120 mg every 8 hours versus placebo in 3:1 randomization (n=59); subsequently, in part 4, maintenance doses of 90, 105, and 120 mg after the 250-mg loading dose were directly randomized against placebo (n=42). Safety, tolerability, and pharmacokinetics were the primary end points; NIHSS at 1 week and Barthel and modified Rankin scores at 1 month were also recorded, but the study was neither designed nor powered to assess efficacy. RESULTS: Rates for mortality and serious adverse events (SAE) were similar in active and placebo groups (9% mortality and 23% SAE for all active combined versus 11% mortality and 33% SAE for placebo). Adverse events associated with AR-R15896AR were dizziness, vomiting, nausea, stupor, and some agitation/hallucination. Withdrawal from treatment occurred only in response to loading doses with AR-R15896AR: placebo, 3 of 46 (7%); 250 mg, 11 of 89 (12%); 275 mg, 1 of 8 (12.5%); and 300 mg, 3 of 15 (20%). No significant difference in outcome was observed between groups. Plasma concentrations of AR-R15896AR were 1524+/-536 ng/mL at the end of the 250-mg loading infusion and were 1847+/-478 ng/mL at steady state after the 9 maintenance doses of 120 mg. CONCLUSIONS: The maximum tolerated loading infusion of AR-R15896AR in this study was 250 mg over a period of 1 hour. Subsequent maintenance infusions of 120 mg every 8 hours were well tolerated. With these doses, putative neuroprotective concentrations of 1240 ng/mL are attained by the loading dose and are satisfactorily maintained thereafter. The loading dose may be improved further by adjustment on an individual patient basis, but tolerability issues remain.
Subject(s)
Excitatory Amino Acid Antagonists/administration & dosage , Pyridines/administration & dosage , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Stroke/drug therapy , Aged , Dose-Response Relationship, Drug , Double-Blind Method , Drug Evaluation , Excitatory Amino Acid Antagonists/adverse effects , Excitatory Amino Acid Antagonists/pharmacokinetics , Female , Humans , Infusions, Intravenous , Male , Pyridines/adverse effects , Pyridines/pharmacokinetics , Severity of Illness Index , Stroke/blood , Survival Rate , Treatment OutcomeABSTRACT
The authors hypothesized that divergent influences of the APOE epsilon4 allele on ischemic and hemorrhagic stroke survival might result from differences in coagulation profiles. In 49 hemorrhagic stroke patients, epsilon4 carriers had higher partial thromboplastin time ratios (p < 0.01) than non-epsilon4 carriers. Among 529 ischemic stroke patients, increasing epsilon4 allele dose was associated with improved survival (p = 0.03) after adjusting for baseline NIH stroke scale (p = 0.00001) and partial thromboplastin time ratio (p = 0.01). Relative anticoagulation does not fully explain the survival advantage in epsilon4-carrying ischemic stroke patients.
Subject(s)
Apolipoproteins E/genetics , Cerebral Hemorrhage/genetics , Cerebral Infarction/genetics , Genotype , International Normalized Ratio , Partial Thromboplastin Time , Alleles , Apolipoprotein E4 , Cerebral Hemorrhage/blood , Cerebral Hemorrhage/mortality , Cerebral Infarction/blood , Cerebral Infarction/mortality , Follow-Up Studies , Genetic Carrier Screening , Humans , Survival RateABSTRACT
Detailed assessment of stroke is essential to distinguish haemorrhage from infarction, to establish the vascular territory affected and to identify patients with carotid stenosis or cardio-embolic disease. Computed tomography scanning should be routinely undertaken. Duplex Doppler sonography and echocardiography should be readily available but used selectively. Hypertension should not be treated early after ischaemic stroke. Issues requiring research include the optimal time to institute treatment, the degree to which blood pressure should be lowered in the presence of carotid stenosis and the value of antihypertensive treatment in normotensive survivors of stroke. Anticoagulation should be more widely applied in the prevention of stroke in patients with atrial fibrillation. Thrombolysis for acute ischaemic stroke has potential benefits and risks. It should be used only within randomised clinical trials, some of which may soon report. Endogenous glutamate causes excitotoxic damage after cerebral ischaemia. Many pharmacological approaches to restrict neuronal loss within the ischaemic penumbra are now in clinical trials. Physicians managing hypertension should take a lead in researching blood pressure management and neuroprotective strategies after acute stroke, and in directing other preventive measures such as anticoagulation for atrial fibrillation.
Subject(s)
Cerebrovascular Disorders/diagnosis , Cerebrovascular Disorders/therapy , Humans , Hypertension/complicationsABSTRACT
OBJECTIVE: To investigate the association between serum cholesterol concentration and cerebrovascular disease. DESIGN: Retrospective study. SETTING: Acute stroke unit of inner city general hospital. SUBJECTS: 977 patients with acute stroke. MAIN OUTCOME MEASURES: Serum total cholesterol concentration, type of stroke investigated by computed tomography or magnetic resonance imaging, three month outcome (good (alive at home) or bad (dead or in care)), long term mortality. RESULTS: After adjustment for known prognostic factors, higher serum cholesterol concentrations were associated with reduced long term mortality after stroke (relative hazard 0.91 (95% confidence interval 0.84 to 0.98) per mmol/l increase in cholesterol) independently of stroke type, vascular territory and extent, age, and hyperglycaemia. Three month outcome was also influenced independently by serum cholesterol (P = 0.024). CONCLUSIONS: Our data suggest an association between poor stroke outcome and lower serum cholesterol concentration. Until a prospective controlled study has confirmed the benefits of lowering cholesterol concentration in elderly subjects, the application of cholesterol lowering guidelines cannot be justified as secondary prevention of acute stroke.
Subject(s)
Cerebrovascular Disorders/mortality , Cholesterol/blood , Adult , Aged , Aged, 80 and over , Bias , Cerebrovascular Disorders/blood , Follow-Up Studies , Humans , Hypercholesterolemia/mortality , Logistic Models , Middle Aged , Prognosis , Retrospective Studies , Risk Factors , Survival RateABSTRACT
OBJECTIVE: To determine whether raised plasma glucose concentration independently influences outcome after acute stroke or is a stress response reflecting increased stroke severity. DESIGN: Long-term follow up study of patients admitted to an acute stroke unit. SETTING: Western Infirmary, Glasgow. SUBJECTS: 811 patients with acute stroke confirmed by computed tomography. Analysis was restricted to the 750 non-diabetic patients. MAIN OUTCOME MEASURES: Survival time and placement three months after stroke. RESULTS: 645 patients (86%) had ischaemic stroke and 105 patients (14%) haemorrhagic stroke. Cox's proportional hazards modelling with stratification according to Oxfordshire Community Stroke Project categories identified increased age (relative hazard 1.36 per decade; 95% confidence interval 1.21 to 1.53), haemorrhagic stroke (relative hazard 1.67; 1.22 to 2.28), time to resolution of symptoms > 72 hours (relative hazard 2.15; 1.15 to 4.05), and hyperglycaemia (relative hazard 1.87; 1.43 to 2.45) as predictors of mortality. The effect of glucose concentration on survival was greatest in the first month. CONCLUSIONS: Plasma glucose concentration above 8 mmol/l after acute stroke predicts a poor prognosis after correcting for age, stroke severity, and stroke subtype. Raised plasma glucose concentration is therefore unlikely to be solely a stress response and should arguably be treated actively. A randomised trial is warranted.
Subject(s)
Cerebrovascular Disorders/complications , Hyperglycemia/etiology , Aged , Cerebrovascular Disorders/mortality , Cohort Studies , Female , Follow-Up Studies , Forecasting , Humans , Male , Prognosis , Risk Factors , Scotland/epidemiology , Stress, Physiological , Survival Analysis , Survival RateABSTRACT
A forty-year-old man developed right-sided neck discomfort whilst cycling to work. On admission to hospital he was found to have signs of bilateral cerebellar dysfunction. Magnetic resonance imaging of the brain demonstrated bilateral areas of cerebellar infarction. Doppler ultrasound of the vertebral arteries was abnormal and non-invasive gradient echo time of flight magnetic resonance angiography confirmed the clinical diagnosis of vertebral artery dissection. The patient was anticoagulated for a period of three months and made a full recovery.
Subject(s)
Magnetic Resonance Imaging , Vertebral Artery Dissection/diagnosis , Adult , Anticoagulants/therapeutic use , Humans , Male , Treatment Outcome , Vertebral Artery Dissection/drug therapy , Vertebral Artery Dissection/physiopathologyABSTRACT
BACKGROUND: Although long-term blood pressure control is known to prevent stroke, acute blood pressure reduction after stroke is associated with worse neurological and functional outcome. VASOACTIVE DRUG TREATMENT AFTER STROKE: Chronic blood pressure reduction for secondary prevention of stroke is presently being tested within the PROGRESS trial. This study uses angiotensin-converting enzyme (ACE) inhibitor-based treatment (perindopril) versus placebo. ACE inhibitors may reduce blood pressure without adversely affecting cerebral blood flow. We have recently reported elsewhere that perindopril 4 mg once daily, initiated within 2-7 days of acute ischaemic stroke, reduces blood pressure without adverse effects on cerebral blood flow as measured by Doppler ultrasound. Nevertheless, the optimal policy with regard to blood pressure management in the first 48 h after acute stroke remains uncertain. CONCLUSIONS: A clinical trial is proposed to establish whether it is better to maintain pre-existing antihypertensive therapy or to discontinue this temporarily.
Subject(s)
Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Blood Pressure/drug effects , Cerebrovascular Disorders/drug therapy , Indoles/therapeutic use , Acute Disease , Cerebrovascular Circulation , Cerebrovascular Disorders/physiopathology , Humans , PerindoprilSubject(s)
Brain Ischemia/drug therapy , Carotid Artery, Internal/drug effects , Fibrinolytic Agents/therapeutic use , Tissue Plasminogen Activator/therapeutic use , Acute Disease , Aged , Carotid Artery, Internal/diagnostic imaging , Humans , Infusions, Intravenous , Male , Recombinant Proteins , UltrasonographyABSTRACT
AIM: To describe the United Kingdom (UK) experience with thrombolytic therapy with intravenous alteplase (rt-PA) for stroke, as captured by the Implementation of Thrombolysis in Stroke (SITS) project. METHODS: The multinational Safe Implementation of Thrombolysis in Stroke-Monitoring Study (SITS-MOST) was an observational study to assess the safety and efficacy of thrombolytic therapy, when administered within the first 3 h after onset of ischaemic stroke. SITS-MOST was embedded within the Safe Implementation of Thrombolysis in Stroke-International Stroke Thrombolysis Register (SITS-ISTR), an internet-based, international monitoring registry for auditing the safety and efficacy of routine therapeutic use of thrombolysis in acute ischaemic stroke. We performed an analysis of data contributed to SITS-MOST and SITS-ISTR from UK centres. RESULTS: A total of 614 patients received thrombolysis for stroke between December 2002 and April 2006, 327 were registered to SITS-MOST and 287 to SITS-ISTR. Thirty-one centres treated patients in the UK, of which 23 registered patients in both SITS-MOST and SITS-ISTR and eight solely to SITS-ISTR. The median age from the UK SITS-MOST was identical to the non-UK SITS-MOST register: 68 years (IQR 59-75). The majority (96.1%) of patients from the UK were treated between 8.00 a.m. and 9.00 p.m., and only 18.4% were treated on weekend days, reflecting the difficulties of maintaining provision of a thrombolytic service out of hours. Median onset-to-treatment-time was 155 min (IQR 130-170 min) for the UK, compared to 140 min (IQR 114-165 min) for the non-UK SITS-MOST group (P < 0.001). UK SITS-MOST patients at baseline had more severe stroke in comparison with non-UK patients [median NIHSS 14.5 (IQR 9-19) vs. 12 (IQR 8-17) (P < 0.001)]. Forty-eight percent of UK patients achieved mRS of 0-2 (independence), compared to 55% of the non-UK SITS-MOST register. There was no significant difference in symptomatic intracerebral haemorrhage rate in the UK compared with the non-UK SITS-MOST patients [2.5% (95% CI 1.3-4.8) vs. 1.7% (95% CI 1.4-2.0) P = 0.28]. In the multivariate analysis, there was no statistically significant difference in any outcome between UK and non-UK SITS-MOST patients. CONCLUSION: Thrombolytic therapy for stroke has been implemented successfully at a small number of UK stroke centres, with patchy provision throughout the country. The low frequency of treatment out with office hours suggests deficient infrastructure to support delivery. UK patients tended to be more severely affected at baseline and to be treated later. Outcomes are comparable to those seen at the non-UK SITS centres.
Subject(s)
Fibrinolytic Agents/therapeutic use , Stroke/drug therapy , Thrombolytic Therapy , Tissue Plasminogen Activator/therapeutic use , Aged , Female , Humans , Injections, Intravenous , Male , Middle Aged , Time Factors , Treatment Outcome , United KingdomABSTRACT
BACKGROUND AND PURPOSE: Remacemide hydrochloride and its principal active desglycinyl metabolite are low-affinity noncompetitive N-methyl-D-aspartate (NMDA)-receptor channel blockers. Remacemide hydrochloride has demonstrated neuroprotection in animal models of hypoxia and ischemic stroke. This study assessed the safety, tolerability, and pharmacokinetics of ascending doses of remacemide hydrochloride in patients with recent onset (within 12 hours) ischemic stroke. METHODS: This was a placebo-controlled, dose escalating, parallel group study. Groups of 8 patients (6 active, 2 placebo) were planned to receive twice-daily treatment, with l00 mg, 200 mg, 300 mg, 400 mg, 500 mg, or 600 mg remacemide hydrochloride given as 2 intravenous infusions followed by 6 days' oral treatment. Patients who were unable to swallow discontinued study medication but continued to be monitored for safety; these patients were replaced. A CT or MRI scan was performed within 48 hours of admission to establish the cause of focal neurological deficit. Patients with ischemic stroke continued in the study. Patients with other causes of focal neurological deficit were withdrawn and replaced. Because the frequency of dysphagia after stroke in the first dose group (100 mg BID) was higher than had been anticipated, the protocol was amended so that subsequent dose groups received 6 intravenous infusions (2 doses per day for 3 days). Neurological and functional outcome data were collected, but the study was not powered to demonstrate drug efficacy. Patient safety was assessed by clinical observation, laboratory tests, and ECGs, while tolerability was assessed by recording adverse events. Blood sampling was included to determine plasma concentrations of remacemide and the desglycinyl metabolite at fixed points during the dosing period. RESULTS: The most common adverse events considered by the investigator to be possibly treatment related were related to the central nervous system (CNS), and these events appeared to increase with dose. Four patients were withdrawn from the study because of CNS-related events: 1 in the placebo group, 1 in the 500 mg BID group, and 2 in the 600 mg BID group. Infusion site reactions and gastrointestinal upset were also reported and considered to be treatment related. One patient in the placebo group and 4 patients in the 600 mg BID dose group experienced vomiting, whereas this event was not reported by patients in the other dose groups. CONCLUSIONS: On the evidence of this study, the maximum well-tolerated dose for remacemide hydrochloride in acute stroke is 400 mg BID. Doses of 200 mg BID or higher attained the putative neuroprotective plasma concentrations of remacemide predicted from animal models (250 to 600 ng/mL). The expected gradual accumulation of active metabolite might suggest that optimal neuroprotective concentrations are unlikely to be achieved within the early hours of treatment at this dose. However, plasma concentrations do not directly reflect brain concentrations, because studies in rats show that remacemide and the desglycinyl metabolite rapidly reach comparable brain concentrations within 1 hour, despite a lower plasma concentration of the metabolite.
Subject(s)
Acetamides/therapeutic use , Brain Ischemia/drug therapy , Cerebrovascular Disorders/drug therapy , Neuroprotective Agents/therapeutic use , Acetamides/administration & dosage , Acetamides/blood , Acetamides/metabolism , Acute Disease , Adult , Aged , Aged, 80 and over , Central Nervous System Diseases/chemically induced , Cerebrovascular Disorders/mortality , Dose-Response Relationship, Drug , Double-Blind Method , Female , Gastrointestinal Diseases/chemically induced , Humans , Male , Middle Aged , Neuroprotective Agents/administration & dosage , Neuroprotective Agents/adverse effects , Neuroprotective Agents/blood , Neuroprotective Agents/metabolism , PlacebosABSTRACT
Although stroke is a major cause of morbidity and mortality, it is only relatively recently that a concerted effort has been made to develop acute treatments. Thrombolytics, such as recombinant tissue plasminogen activator (rt-PA), may benefit selected patients within 3 h of cerebral infarction. CUrrently, rt-PA is only licensed for use in the United States. Many potential strategies for neuroprotection exist and are currently under investigation. Because the mechanisms of neurotoxicity involve numerous interdependent processes, it may be that the interpretation of a single site in the cascade of events is insufficient to provide effective neuroprotection. Drugs acting at several sites in the neurotoxic cascade may be more effective, and the results of Phase III studies with the novel neoroprotectant lubeluzole are anticipated.
Subject(s)
Cerebrovascular Disorders/drug therapy , Neuroprotective Agents/therapeutic use , Thrombolytic Therapy , Cerebrovascular Disorders/etiology , Cerebrovascular Disorders/physiopathology , Disease Models, Animal , Humans , Neuroprotective Agents/pharmacology , Piperidines/pharmacology , Piperidines/therapeutic use , Plasminogen Activators/therapeutic use , Receptors, N-Methyl-D-Aspartate/physiology , Recombinant Proteins/therapeutic use , Thiazoles/pharmacology , Thiazoles/therapeutic use , Tissue Plasminogen Activator/therapeutic useABSTRACT
BACKGROUND: The therapeutic time window for thrombolysis appears to be extremely short, probably because of the hemorrhagic complications associated with late reperfusion of ischemic brain tissue. Other neuroprotective forms of treatment continue to be developed, although their efficacy has yet to be conclusively proved in patients. The duration of treatment in recent phase 3 trials ranges from a single bolus injection to 12 weeks of oral therapy. SUMMARY OF REVIEW: In this article we discuss the factors that should influence the choice of route and duration of treatment. Excitotoxic injury following stroke evolves over at least 4 hours in rodents and possibly beyond 48 hours in humans. In addition, autoregulation and local cerebral perfusion are deranged for approximately 72 hours in patients with stroke. Neuroprotection should provide cover during this critical time. CONCLUSIONS: Important considerations influencing drug administration should include the pharmacology of the compound (pharmacokinetics, mechanism of action, preclinical toxicity, and pharmaceutical properties), its safety and tolerability in patients, and the likelihood of continuing or recurrent cerebral ischemia, along with practical issues such as ease of administration and interactions with early rehabilitation and other therapies. Optimization of treatment will be possible only when neuroprotection is confirmed to be effective.
Subject(s)
Brain Ischemia/drug therapy , Fibrinolytic Agents/therapeutic use , Neuroprotective Agents/therapeutic use , Animals , Brain Ischemia/physiopathology , Fibrinolytic Agents/adverse effects , Hemodynamics/drug effects , Humans , Neuroprotective Agents/adverse effects , Thrombolytic Therapy , Time FactorsABSTRACT
BACKGROUND AND PURPOSE: GV150526 is a novel glycine site antagonist at the N-methyl-D-aspartate receptor complex. It is a potent neuroprotective agent in animal models of stroke, including permanent middle cerebral artery occlusion in the rat. Unlike antagonists at the glutamate ligand binding site, GV150526 appears to be free of hemodynamic and central nervous system adverse effects. The purpose of this study was to assess the safety, tolerability, and pharmacokinetics of loading and maintenance infusions of GV150526 in patients with acute stroke. METHODS: This was a randomized, placebo-controlled, parallel-group, ascending-dose study conducted in 2 phases. In part A of the study, loading doses of 50, 100, 200, 400, or 800 mg were administered. In part B, the maximum loading dose from part A was followed by maintenance infusions (5 infusions at 12-hour intervals), aiming to maintain neuroprotective levels. Safety data were collected throughout. The study was not designed to test efficacy, but outcome data (Barthel Index and National Institutes of Health Stroke Scale) were collected. RESULTS: Sixty-six patients were recruited to the study over 11 months; 18 patients received placebo. GV150526 was well tolerated by the 48 patients who received it. There was no excess of central nervous system or hemodynamic adverse events compared with placebo. Minor abnormalities in liver function tests were observed in association with the higher maintenance doses tested. Four of 7 patients receiving the 800-mg loading dose followed by 400 mg BID and 1 of 6 patients who received the 200-mg BID maintenance dose showed a small rise in bilirubin, and 3 patients had increases in transaminases; the mean values at 72 hours remained under twice the upper limit of normal. These changes were asymptomatic and resolved within 10 days. CONCLUSIONS: GV150526 is an emerging neuroprotective agent, with no apparent significant central nervous system or hemodynamic effects. Dose-limiting effects appear to be restricted to mild transient and asymptomatic rises in bilirubin and/or transaminases, primarily observed at high maintenance doses, and there were no findings that should preclude further clinical development.
Subject(s)
Cerebrovascular Disorders/drug therapy , Glycine Agents/administration & dosage , Indoles/administration & dosage , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Acute Disease , Aged , Alanine Transaminase/blood , Alkaline Phosphatase/blood , Bilirubin/blood , Electrocardiography , Female , Glycine Agents/adverse effects , Glycine Agents/pharmacokinetics , Humans , Indoles/adverse effects , Indoles/pharmacokinetics , Male , Patient Compliance , Treatment Outcome , gamma-Glutamyltransferase/bloodABSTRACT
BACKGROUND AND PURPOSE: The relationship between high blood pressure and the incidence of stroke is well established. Currently the effects of lowering blood pressure in patients with established cerebrovascular disease is undetermined, and there is continuing concern regarding the treatment of patients soon after a stroke event. Angiotensin-converting enzyme inhibitors maintain cerebral blood flow despite lowering blood pressure in patients with heart failure and otherwise uncomplicated hypertension. We tested the hypothesis that perindopril, an angiotensin-converting enzyme inhibitor with a gradual onset of action and a minimal first-dose hypotensive effect, lowers blood pressure without adversely affecting cerebral blood flow in patients 2 to 7 days after symptoms of cerebral infarction. METHODS: Patients were randomized to receive 15 days of oral perindopril (4 mg) or placebo in a double-blind study. Blood pressure was monitored semiautomatically. Cerebral blood flow was calculated from internal carotid artery and vertebral Doppler ultrasound, supplemented by middle cerebral artery blood velocities. RESULTS: Twenty-four patients completed the protocol; four additional patients were withdrawn for reasons unrelated to treatment. Patients on perindopril had a placebo-corrected reduction in blood pressure of 19/11 mm Hg. Blood pressure remained reduced after 2 weeks of treatment. In contrast, total cerebral blood flow was unaffected by perindopril. Neurological symptoms improved similarly in both groups. CONCLUSIONS: Perindopril was well tolerated and effectively reduced blood pressure without reducing carotid territory blood flow in patients with symptoms of recent cerebral ischemia.
Subject(s)
Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Brain Ischemia/drug therapy , Cerebrovascular Disorders/drug therapy , Hypertension/drug therapy , Indoles/therapeutic use , Aged , Aged, 80 and over , Blood Pressure/drug effects , Brain Ischemia/diagnostic imaging , Brain Ischemia/physiopathology , Cerebrovascular Circulation/drug effects , Cerebrovascular Disorders/diagnostic imaging , Cerebrovascular Disorders/physiopathology , Double-Blind Method , Female , Humans , Hypertension/diagnostic imaging , Male , Middle Aged , Perindopril , Placebos , UltrasonographyABSTRACT
OBJECTIVE: The objective of this study was to characterize the pharmacokinetics of gavestinel in patients with acute stroke. METHODS: Gavestinel was administered as an 800-mg loading dose and followed by either 100-, 200-, or 400-mg maintenance doses given every 12 h for five doses. Blood and urine samples were collected for pharmacokinetic evaluation. The pharmacokinetics of gavestinel were determined using compartmental analysis. RESULTS: The mean clearance (CL) and central (Vc) and steady-state (Vss) volumes of distribution across the dose groups were 0.31-0.40 l x h(-1), 3.3-3.9 l, and 9.8-17 l, respectively. The mean terminal half-life ranged from 29 h to 56 h. Gavestinel was extensively bound to plasma protein (median percentage free <0.01). During gavestinel administration, some patients exhibited elevated levels of bilirubin, which may be the result of shared mechanisms of elimination (glucuronide conjugation and excretion in bile). CONCLUSIONS: This study characterized the pharmacokinetics of gavestinel following multiple doses in acute stroke patients and showed that the pharmacokinetics are similar for increasing maintenance doses. The high protein binding of gavestinel was confirmed in acute stroke patients. A pharmacokinetic interaction between gavestinel and bilirubin may contribute to the increase in bilirubin.
Subject(s)
Glycine Agents/pharmacokinetics , Indoles/pharmacokinetics , Stroke/metabolism , Aged , Aged, 80 and over , Bilirubin/blood , Blood Proteins/metabolism , Dose-Response Relationship, Drug , Double-Blind Method , Female , Humans , Indoles/blood , Indoles/metabolism , Liver Function Tests , Male , Metabolic Clearance Rate , Middle Aged , Protein Binding , Stroke/drug therapyABSTRACT
BACKGROUND AND PURPOSE: Aptiganel (CNS 1102) is a selective, noncompetitive antagonist that acts on the ion channel associated with the N-methyl-D-aspartate (NMDA) receptor and is neuroprotective in experimental focal cerebral ischemia models at a plasma concentration of 10 ng/mL. In human volunteers, dose-limiting effects of aptiganel are blood pressure increases and central nervous system (CNS) excitation or depression. This study assessed the safety and tolerability of non-weight-adjusted doses of aptiganel in patients with acute ischemic stroke. METHODS: This was a double-blind, randomized, placebo-controlled multicenter study in patients presenting within 24 hours of acute ischemic stroke. Ascending single intravenous bolus doses of aptiganel (3, 4.5, 6, and 7.5 mg) were assessed in 21 patients with a 3:1 active drug:placebo randomization schedule. In 15 subsequent patients, selected bolus doses were followed by constant intravenous infusion for 6 to 12 hours (6 mg plus 1 mg/h, n=10; then 4.5 mg plus 0.75 mg/h, n=15) in a 4:1 randomization schedule. Prospectively collected pharmacokinetic data guided selection of infusion rates. Neurological and functional status were recorded at entry and after 1 week, although the study was not designed to test efficacy. RESULTS: Forty-six patients were randomized from 4 centers (3 in the United States and 1 in the United Kingdom): 36 received aptiganel HCl, and 10 were given placebo. Hypertension and CNS events were commonly reported after a bolus dose of 7.5 mg and after a 6-mg bolus followed by an infusion of 1 mg/h. The lower regimen of 4.5-mg bolus followed by infusion of 0.75 mg/h achieved plasma aptiganel concentrations of >10 ng/mL and was well tolerated by patients but still raised systolic blood pressure by approximately 30 mm Hg over baseline. CONCLUSIONS: A 4.5-mg intravenous bolus of aptiganel HCl followed by infusion of 0.75 mg/h for 12 hours is a tolerable dose that can produce plasma drug concentrations shown to be neuroprotective in animal models. However, increases in systolic blood pressure and an excess of CNS effects were both observed at this dose.
Subject(s)
Excitatory Amino Acid Antagonists/adverse effects , Guanidines/adverse effects , Ischemic Attack, Transient/drug therapy , Neuroprotective Agents/adverse effects , Adult , Aged , Aged, 80 and over , Blood Pressure/drug effects , Double-Blind Method , Humans , Middle Aged , Reference Values , Treatment OutcomeABSTRACT
BACKGROUND AND PURPOSE: Polymorphism of the apolipoprotein E gene (APOE) may influence outcome after traumatic brain injury and intracerebral hemorrhage, with the epsilon4 allele being associated with poorer prognosis. We investigated APOE allele distribution in acute stroke and the effect of the epsilon4 allele on outcome. METHODS: APOE genotypes were determined in 714 stroke patients: 640 ischemic stroke and 74 intracerebral hemorrhage patients. The survival effect of the epsilon4 allele was assessed with the use of a stratified log-rank test. A Cox proportional hazards regression model was used to estimate the independent effect of epsilon4 dose (0, 1, or 2) on survival, and logistic regression was used to determine the effect on 3-month outcome (good if alive at home, poor if in care or dead). RESULTS: Allele distribution matched the general population with no difference between the ischemic and hemorrhagic groups. Survival in the entire cohort was unaffected by epsilon4 dose. Improved survival with increasing epsilon4 dose was found in the ischemic group (relative hazard=0.76 per allele; P=0.04). If transient ischemic attacks were excluded, a trend for improved survival persisted (P=0.06). With intracerebral hemorrhage, a trend was seen toward reduced survival with epsilon4 (P=0.07, log-rank test). Three-month outcome in the ischemic group was unaffected by epsilon4 dose, and a trend toward poorer outcome with epsilon4 was seen for intracerebral hemorrhage (P=0.10). CONCLUSIONS: The APOE epsilon4 allele had divergent effects on survival and outcome in ischemic and hemorrhagic strokes in this population. The reported adverse effect on patients with intracerebral hemorrhage was supported. The favorable survival effect on ischemic stroke patients requires further study.