Autologous hematopoietic stem cell transplantation for multiple sclerosis: Long-term follow-up data from Norway.

BACKGROUND: Autologous hematopoietic stem cell transplantation (HSCT) is a potent treatment option for patients with aggressive relapsing-remitting multiple sclerosis (RRMS). OBJECTIVE: To evaluate long-term outcomes of HSCT in MS. METHODS: National retrospective single-center observational study of patients with aggressive RRMS that underwent HSCT in Norway from January 2015 to January 2018. Criteria for receiving HSCT included at least two clinical relapses the last year while on disease modifying treatment (DMT). RESULTS: In total, 29 patients, with a mean follow-up time of 70 months (standard deviation:14.3), were evaluated. Twenty patients (69%) had sustained no evidence of disease activity (NEDA-3) status, 24 (83%) were relapse-free, 23 (79%) free of magnetic resonance imaging (MRI) activity, and 26 (90%) free of progression. Number of patients working full-time increased from 1 (3%), before HSCT, to 10 (33%) after 2 years and 15 (52%) after 5 years. CONCLUSION: HSCT offers long-term disease-free survival with successively increasing work participation in patients with aggressive MS resistant to DMTs.

Prolonged and repeated microemboli detection in acute ischemic stroke - The Norwegian Microemboli in Acute Stroke Study (NOR-MASS).

OBJECTIVES: Cerebral microemboli can be detected by transcranial Doppler monitoring (TCDM) and may elucidate stroke etiology, the effect of preventive therapy, and the risk of stroke recurrence. Microemboli detection is usually performed for up to 60 minutes, but due to temporal variability, microembolization may be missed if the monitoring time is too short. We aimed to assess the time course of microembolization in acute ischemic stroke and explore the utility of prolonged and repeated microemboli detection. MATERIALS AND METHODS: Patients with suspected ischemic stroke and symptom onset within 24 hours were examined with bilateral, stationary TCDM for one hour followed by unilateral, ambulatory TCDM for two hours. Unilateral TCDM was repeated for the following two days and after three months. RESULTS: We included 47 patients, of which 41 had ischemic stroke, five had transient ischemic attack, and one had amaurosis fugax. Microemboli were detected in 60 % of patients. The occurrence was highest within 24 hours after onset and significantly lower at three months. Prolonged and repeated microemboli detection yielded only one additional microemboli-positive patient. Hence, patients who initially were microemboli negative tended to remain negative. We could not demonstrate an association between microemboli occurrence and clinical outcome or stroke recurrence. CONCLUSIONS: Microembolic signals are frequent within 24 hours after ischemic stroke onset, but prolonged and repeated microemboli detection did not increase the yield of MES positive patients. CLINICAL TRIAL REGISTRATION-URL: http://www. CLINICALTRIALS: gov. Unique identifier: NCT03543319.

The Therapeutic Mechanisms of Mesenchymal Stem Cells in MS-A Review Focusing on Neuroprotective Properties.

In multiple sclerosis (MS), there is a great need for treatment with the ability to suppress compartmentalized inflammation within the central nervous system (CNS) and to promote remyelination and regeneration. Mesenchymal stem cells (MSCs) represent a promising therapeutic option, as they have been shown to migrate to the site of CNS injury and exert neuroprotective properties, including immunomodulation, neurotrophic factor secretion, and endogenous neural stem cell stimulation. This review summarizes the current understanding of the underlying neuroprotective mechanisms and discusses the translation of MSC transplantation and their derivatives from pre-clinical demyelinating models to clinical trials with MS patients.

Characteristics and predictors of stroke mimics in young patients in the norwegian tenecteplase stroke trial (NOR-TEST).

BACKGROUND: Several studies have shown that stroke mimics occur more often among young patients. Our aims were to identify the common mimics in young patients under the age of 60 years who received thrombolysis, to analyze the risk of hemorrhage after treatment with thrombolysis, and to identify risk factors and clinical parameters that might identify mimics in this group. METHODS: Norwegian Tenecteplase Stroke Trial was a phase-3 trial investigating safety and efficacy of tenecteplase vs. alteplase in patients with acute ischemic stroke. Patients diagnosed with either acute cerebral ischemia or transient ischemic attack were categorized as stroke group, and patients with any diagnosis other than ischemic stroke or transient ischemic attack as mimics group. Patients were grouped post-hoc into young (< 60 years) and old (≥ 60 years). Logistic regression analyses were performed with mimics vs. stroke as dependent variable to identify predictors of mimics. RESULTS: Of the 1091 patients included in the trial, 211 patients (19.3%) were under the age of 60 years. Out of the 1091 patients, 434 (39.8%) were female, median age 77 years (18-99 years), and median NIHSS was 4. Sixty-nine patients (32.7%) out of the 211 patients under the age of 60 were diagnosed as mimic. Mimics were significantly more frequent among the young (OR = 3.3, 32.7% vs. 12.8%, p = < 0.001). The most frequent mimics diagnoses among patients under 60 years of age were migraine (11.8%), no definite diagnosis (11.4%) and peripheral vertigo (3.3%). Mimics were independently associated with age < 50 years (OR = 4.97, p = < 0.001), not currently working/studying (OR = 3.38, p = 0.002) and not having aphasia on admission (OR = 2.95, p = 0.025). None of the mimics under the age of 60 years had symptomatic or asymptomatic intracerebral hemorrhage as a complication to thrombolysis. CONCLUSION: We found significantly more mimics in the young, of which migraine was the most predominant diagnosis. Thrombolysis with alteplase or tenecteplase did not cause ICH in any mimics under 60 years.

Sex differences in the Norwegian Tenecteplase Trial (NOR-TEST).

BACKGROUND AND PURPOSE: Sex differences in acute ischemic stroke is of increasing interest in the era of precision medicine. We aimed to explore sex disparities in baseline characteristics, management and outcomes in patients treated with intravenous thrombolysis included in the Norwegian Tenecteplase trial (NOR-TEST). METHODS: NOR-TEST was an open-label, randomized, blinded endpoint trial, performed from 2012 to 2016, comparing treatment with tenecteplase to treatment with alteplase within 4.5 h after acute ischemic stroke symptom onset. Sex differences at baseline, treatment and outcomes were compared using multivariable logistic regression models. Heterogeneity in treatment was evaluated by including an interaction term in the model. RESULTS: Of 1100 patients enrolled, 40% were women, and in patients aged >80 years, the proportion of women was greater than men (19% vs. 14%; p = 0.02). Women had a lower burden of cardiovascular risk factors, such as diabetes mellitus (11% vs. 15%; p = 0.05) and a higher mean high-density lipoprotein cholesterol level (1.7 ± 0.6 mmol/L vs. 1.3 ± 0.4 mmol/L; p < 0.001), and a higher proportion of women had never smoked (45% vs. 33%; p < 0.001) compared with men. While there was no sex difference in time from onset of symptoms to admission, door to needle time or in-hospital workup, women were admitted with more severe stroke (National Institutes of Health Stroke Scale [NIHSS] score 6.2 ± 5.6 vs. 5.3 ± 5.1; p = 0.01). Stroke mimic diagnosis was more common in women (21% vs. 15%; p = 0.01). There were no significant sex differences in clinical outcome, measured by the NIHSS, the modified Rankin Scale, intracranial hemorrhage and mortality. CONCLUSION: Women were underrepresented in number in NOR-TEST. The included women had a lower cardiovascular risk factor burden and more severe strokes.

Safety and Outcomes of Tenecteplase in Moderate and Severe Ischemic Stroke.

Background and Purpose- Tenecteplase represents a promising alternative to alteplase as thrombolytic treatment in acute ischemic stroke. There are limited data on tenecteplase 0.4 mg/kg in patients with increased stroke severity. We aimed to assess safety and efficacy of tenecteplase 0.4 mg/kg in patients with moderate and severe ischemic stroke. Methods- NOR-TEST (Norwegian Tenecteplase Stroke Trial) was a phase III trial designed to investigate the safety and efficacy of tenecteplase 0.4 mg/kg versus alteplase 0.9 mg/kg in ischemic stroke. In this post hoc analysis, moderate stroke was defined as admission National Institutes of Health Stroke Scale; 6 to 14 and severe stroke as National Institutes of Health Stroke Scale; ≥15. Rates of favorable outcome at 90 days, symptomatic intracerebral hemorrhage (sICH), and mortality after 7 and 90 days were assessed. Results- In patients with moderate stroke (n=261), there were no differences in rates of favorable outcome, sICH, or mortality between tenecteplase and alteplase. In patients with severe stroke (n=87), there were no differences in outcome, frequency of sICH, or mortality at 7 days, but all-cause mortality at 90 days was increased in patients treated with tenecteplase (10 [26.3%] versus 4 [9.1%]; P=0.045). One patient died of sICH in the tenecteplase group, and 2 patients died of sICH in the alteplase group. Conclusions- Rates of favorable outcome and sICH were similar between treatment groups in patients with moderate and severe stroke. Mortality after 90 days was increased in patients with severe stroke receiving tenecteplase. Future studies assessing tenecteplase 0.4 mg/kg should monitor safety parameters closely in patients with severe stroke. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT01949948.

When to Screen Ischaemic Stroke Patients for Cancer.

BACKGROUND AND PURPOSE: Ischemic stroke can be the first manifestation of cancer and it is therefore important to ascertain which stroke patients should be considered for cancer-diagnostic investigations. We aimed to determine the frequency of active cancer in patients with acute ischemic stroke and to compare clinical findings in stroke patients with active cancer to ischemic stroke patients with no history of cancer. Finally, we aimed to develop a predictive and feasible score for clinical use to uncover underlying malignancy. METHODS: All ischemic stroke patients admitted to the stroke unit in the Department of Neurology, Haukeland University Hospital were consecutively included in the Norwegian Stroke Research Registry (NORSTROKE). Stroke etiology was determined by the Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria. Data on cancer diagnoses was obtained from patients' medical records and the Cancer Registry of Norway. Active cancer was defined as cancer diagnosis, metastasis of known cancer, recurrent cancer or receiving cancer treatment, all within 12 months before or after the index stroke. Based on variables independently associated with active cancer, a predictive score was developed using the area under the receiver operating characteristic (AUC-ROC) curves. Bayes' theorem was used to calculate post-test probabilities of active cancer. RESULTS: Of the 1,646 ischemic stroke patients included, 82 (5.0%) had active cancer. Increased D-dimer (OR = 1.1, 95% CI: 1.1-1.2, p = <0.001), lower Hb (OR = 0.6, 95% CI: 0.5-0.7, p = <0.001), smoking (OR = 2.2, 95% CI: 1.2-4.3, p = 0.02) and suffering a stroke of undetermined etiology (OR = 1.9, 95% CI: 1.1-3.3, p = 0.03) were factors independently associated with active cancer. These were included in the final predictive score which gave an AUC of 0.73 (95% CI: 0.65-0.81) in patients younger than 75 years of age. Assuming the prevalence of cancer to be 5%, the score shows that if a patient fulfills all 3 score points, the probability of active cancer is 53%. CONCLUSIONS: Active cancer was found in 5% of our ischemic stroke patients. We found that a clinical score comprising elevated D-dimer ≥3 mg/L, lower Hb ≤12.0 g/dL and previous or current smoking is feasible for predicting active cancer in ischemic stroke patients.

A dark side of subcortical diffusion-weighted lesions? Characteristics, cause, and outcome in large subcortical infarction: the Bergen Norwegian stroke cooperation study.

BACKGROUND AND PURPOSE: Diffusion-weighted imaging (DWI) is highly accurate in identifying and locating ischemic stroke injury. Few studies using DWI have investigated large subcortical infarctions (LSIs). We aimed to study clinical characteristics, cause, and outcome in patients with ischemic stroke with LSI diagnosed on DWI and compare these with those who had lacunar DWI lesions or DWI lesions located elsewhere. METHODS: Patients with stroke admitted between February 2006 and July 2013 were prospectively registered in a stroke database and examined with DWI. Patients with DWI lesions classified as LSI (subcortical, ≥15 mm) were compared with those with lacunar lesions (subcortical, <15 mm, lacunar infarction [LI]), cortical lesions (cortical infarction [CI]), or no LSI, which included LI, CI, mixed cortical-subcortical, cerebellar, brain stem, and combined lesion locations. RESULTS: A total of 1886 patients with ischemic stroke were included, of which 128 patients (6.8%) had LSI, 317 (16.8%) LI, and 544 (28.8%) CI. The no LSI group included 1758 patients. Occlusive pathology in the proximal middle cerebral artery was more frequent in patients with acute stroke with LSI. Lacunar syndrome was associated with LSI when compared with CI and no LSI. Unknown cause was frequent in the LSI group (60.4%) and independently associated with LSI in the LSI versus LI (P<0.001), LSI versus CI (P=0.002), and LSI versus no LSI population (P<0.001). LSI was independently associated with unfavorable outcome, whether compared with LI (P=0.002), CI (P<0.001), or no LSI (P=0.002). CONCLUSIONS: LSI is associated with distinct clinical characteristics, unknown cause, and unfavorable outcome, which separates this stroke entity from patients with lacunar subcortical DWI lesions or DWI lesions located elsewhere.

Diffusion-weighted lesions in stroke patients with transient symptoms--where are they located?

BACKGROUND: MR diffusion-weighted imaging (DWI) has revolutionized neuroimaging and contributed to a tissue-based redefinition of transient ischemic attack (TIA). Stroke patients with DWI lesions may have neurological symptoms that resolve completely within 24 h, suggesting successful vessel recanalization. Prior studies of stroke patients with transient symptoms have not found any predilection for DWI lesions in any specific territory. Other studies have, however, reported an association between higher brain dysfunction and presence of DWI lesions in patients with transient ischemic symptoms, suggesting a high rate of cortical affection in these patients. We sought to see whether DWI location in stroke patients with transient symptoms <24 h differed from those with persistent symptoms ≥ 24 h. We hypothesized an association between transient symptoms <24 h and cortical DWI lesion localization due to a possible higher rate of vessel recanalization in patients with transient symptoms causing distal cortical infarctions. METHODS: Ischemic stroke patients examined with DWI and admitted within 24 h after symptom onset between February 2006 and November 2013 were prospectively registered in a database (The Bergen NORSTROKE Registry). Based on neurological examination 24 h after admission, patients were classified as having either transient symptoms <24 h (DWI <24) or persistent symptoms ≥ 24 h (DWI ≥ 24). DWI lesions were classified into different groups depending on lesion location: cortical lesions, confined to the supratentorial cortex; large subcortical lesions, located in the hemispheric white matter, basal ganglia, internal capsule, thalamus or corona radiate with a diameter ≥ 15 mm; lacunar lesions, located in the same territory as large subcortical lesions with a diameter <15 mm; mixed cortical-subcortical lesions, located in both supratentorial cortex and subcortex; cerebellar lesions, confined to the cerebellum; brain stem lesions, confined to the brain stem; multiple locations, located in more than one of the above defined areas. RESULTS: A total of 142 ischemic stroke patients had DWI <24 and 830 DWI ≥ 24. Cortical DWI location was more frequent in patients with DWI <24 (54.2% vs. 29.5%, p < 0.001), while proportions of mixed cortical-subcortical lesions (13.4% vs. 26.5%, p = 0.001) and lesions with multiple locations (5.6% vs. 11.1%, p = 0.048) were less frequent as compared to DWI ≥ 24. Cortical DWI location was independently associated with DWI <24 when adjusted for confounders in multiple regression analyses (OR 1.89, 95% CI 1.28-2.81, p = 0.001). CONCLUSION: Cortical DWI location was independently associated with transient stroke symptoms <24 h. This may be explained by vessel recanalization, resulting in upstream transportation of remaining particles and distal cortical lesions.

Neural regeneration in the human central nervous system-from understanding the underlying mechanisms to developing treatments. Where do we stand today?

Mature neurons in the human central nervous system (CNS) fail to regenerate after injuries. This is a common denominator across different aetiologies, including multiple sclerosis, spinal cord injury and ischemic stroke. The lack of regeneration leads to permanent functional deficits with a substantial impact on patient quality of life, representing a significant socioeconomic burden worldwide. Great efforts have been made to decipher the responsible mechanisms and we now know that potent intra- and extracellular barriers prevent axonal repair. This knowledge has resulted in numerous clinical trials, aiming to promote neuroregeneration through different approaches. Here, we summarize the current understanding of the causes to the poor regeneration within the human CNS. We also review the results of the treatment attempts that have been translated into clinical trials so far.

Elevated admission blood pressure and stroke severity in acute ischemic stroke: the Bergen NORSTROKE Study.

BACKGROUND: Transient elevated blood pressure (BP) is frequent in patients presenting with acute ischemic stroke. The pathophysiology of this response is not clear and its effect on clinical outcome has shown contradictory results. Some studies have suggested that BP elevation may represent a protective response to enhance perfusion in ischemic brain tissue. In this study, we aimed to explore the association between elevated admission BP and stroke severity in the acute phase of ischemic stroke. If it is true that elevated BP represents a protective response in acute ischemia, we expected an inverse association between elevated BP and admission stroke severity, and a positive association between elevated BP and complete neurological recovery within 24 h and/or favorable short-term outcome. METHODS: Patients with ischemic stroke with hospital admission <6 h after symptom onset were prospectively included in a stroke registry (Bergen NORSTROKE Registry). BP was measured immediately after admission in all patients. Elevated BP was defined as systolic BP ≥140 mm Hg or diastolic BP ≥90 mm Hg. The National Institutes of Health Stroke Scale (NIHSS) was used to assess stroke severity upon admission. Mild stroke was defined as NIHSS score <8, moderate stroke as NIHSS score 8-14, and severe stroke as NIHSS score ≥15. Complete neurological recovery (CNR) was defined as no persistent ischemic stroke symptoms at 24 h after admission. Favorable short-term outcome was defined as a modified Rankin Scale score of 0 or 1 at day 7. RESULTS: A total of 749 patients with ischemic stroke were included, of which 621 patients (82.9%) presented with elevated BP. Elevated BP was independently associated with mild stroke (odds ratio, OR: 2.12; 95% CI: 1.39-3.24; p < 0.001), whereas lack of elevated BP was independently associated with severe stroke (OR: 0.41; 95% CI: 0.25-0.68; p < 0.001). There was a nonsignificant association between elevated BP and CNR (OR: 2.11; 95% CI: 0.96-4.68; p = 0.063), yet no association between elevated BP and favorable short-term outcome (OR: 0.97; 95% CI: 0.59-1.59; p = 0.906) when adjusted for confounders. CONCLUSION: Our study showed an inverse association between elevated BP and stroke severity on admission, where elevated BP was associated with mild stroke and lack of elevated BP was associated with severe stroke. This could be explained by a protective effect of elevated BP in the acute phase of ischemic stroke, although the absence of association between elevated BP and favorable outcome argues against this hypothesis.

Tenecteplase, 0.4 mg/kg, in Moderate and Severe Acute Ischemic Stroke: A Pooled Analysis of NOR-TEST and NOR-TEST 2A.

Background The optimal dose of tenecteplase in acute ischemic stroke remains to be defined. We present a pooled analysis of the 2 NOR-TESTs (Norwegian Tenecteplase Stroke Trials) exploring the efficacy and safety of tenecteplase, 0.4 mg/kg. Methods and Results We retrospectively reviewed 2 PROBE (Prospective Randomized Open, Blinded End-point) trials, NOR-TEST and NOR-TEST 2A. Patients were randomized to either tenecteplase, 0.4 mg/kg, or alteplase, 0.9 mg/kg. The primary end point was favorable functional outcome at 3 months (modified Rankin Scale score, 0-1) or return to baseline if prestroke modified Rankin Scale score was 2. Secondary end points included favorable functional and clinical outcome and safety data. The pooled analysis includes patients with National Institutes of Health Stroke Scale score ≥6 from both trials and an additional post hoc analysis of patients with National Institutes of Health Stroke Scale score ≤5 from NOR-TEST. The per-protocol analysis contains 483 patients, of whom 235 were assigned to tenecteplase and 248 were assigned to alteplase. In per-protocol analysis, functional outcome was better in the alteplase arm with cutoff modified Rankin Scale score of 2 (odds ratio [OR], 0.52 [95% CI, 0.33-0.80]; P=0.003) and expressed by ordinal shift analysis (OR, 1.64 [95% CI, 1.17-2.28]; P=0.004). Mortality at 3 months was higher in the tenecteplase arm (OR, 2.48 [95% CI, 1.20-5.10]; P=0.01). Mortality and intracranial hemorrhage rates were higher in the severe stroke group randomized to tenecteplase, whereas these rates were similar for alteplase and tenecteplase in moderate and mild stroke. Conclusions Tenecteplase, 0.4 mg/kg, is unsafe in moderate and severe stroke, and the risk of death and intracranial hemorrhage probably increases with stroke severity. A lower tenecteplase dose should be tested in future trials. Registration URL: https://www.clinicaltrials.gov; Unique identifiers: NCT01949948, NCT03854500.

The neuroprotective potential of mesenchymal stem cells from bone marrow and human exfoliated deciduous teeth in a murine model of demyelination.

INTRODUCTION: Multiple sclerosis (MS) is characterized by chronic inflammation, demyelination, and axonal degeneration within the central nervous system (CNS), for which there is no current treatment available with the ability to promote neuroprotection or remyelination. Some aspects of the progressive form of MS are displayed in the murine cuprizone model, where demyelination is induced by the innate immune system without major involvement of the adaptive immune system. Mesenchymal stem cells (MSCs) are multipotent cells with immunomodulatory and neuroprotective potential. In this study, we aimed to assess the neuroprotective potential of MSCs from bone marrow (BM-MSCs) and stem cells from human exfoliated deciduous teeth (SHED) in the cuprizone model. METHODS: Human BM-MSCs and SHED were isolated and characterized. Nine-week-old female C57BL/6 mice were randomized to receive either human BM-MSCs, human SHED or saline intraperitoneally. Treatments were administered on day -1, 14 and 21. Outcomes included levels of local demyelination and inflammation, and were assessed with immunohistochemistry and histology. RESULTS: BM-MSCs were associated with increased myelin content and reduced microglial activation whereas mice treated with SHED showed reduced microglial and astroglial activation. There were no differences between treatment groups in numbers of mature oligodendrocytes or axonal injury. MSCs were identified in the demyelinated corpus callosum in 40% of the cuprizone mice in both the BM-MSC and SHED group. CONCLUSION: Our results suggest a neuroprotective effect of MSCs in a toxic MS model, with demyelination mediated by the innate immune system.

Safety and Clinical Efficacy of Mesenchymal Stem Cell Treatment in Traumatic Spinal Cord Injury, Multiple Sclerosis and Ischemic Stroke - A Systematic Review and Meta-Analysis.

Background: Mesenchymal stem cells (MSCs) is an attractive candidate in regenerative research and clinical trials have assessed their therapeutic potential in different neurological conditions with disparate etiologies. In this systematic review, we aimed to assess safety and clinical effect of MSC treatment in traumatic spinal cord injury (TSCI), multiple sclerosis (MS) and ischemic stroke (IS). Methods: A systematic search was performed 2021-12-10 in MEDLINE, EMBASE, Web of Science and Cochrane where clinical studies assessing MSC treatment in TSCI, MS or IS were included. Studies without control group were excluded for efficacy analysis, but included in the safety analysis. For efficacy, AIS score, EDSS score and mRS were used as clinical endpoints and assessed in a meta-analysis using the random effects model. Findings: Of 5,548 identified records, 54 studies were included. Twenty-six studies assessed MSC treatment in TSCI, 14 in MS and nine in IS, of which seven, seven and five studies were controlled, respectively. There were seven serious adverse events (SAEs), of which four were related to the surgical procedure and included one death due to complications following the implantation of MSCs. Three SAEs were considered directly related to the MSC treatment and all these had a transient course. In TSCI, a meta-analysis showed no difference in conversion from AIS A to C and a trend toward more patients treated with MSCs improving from AIS A to B as compared to controls (p = 0.05). A subgroup analysis performed per protocol, showed more MSC treated patients improving from AIS A to C in studies including patients within 8 weeks after injury (p = 0.04). In MS and IS, there were no significant differences in clinical outcomes between MSC treated patients and controls as measured by EDSS and mRS, respectively. Interpretation: MSC-treatment is safe in patients with TSCI, MS and IS, although surgical implantation of MSC led to one fatal outcome in TSCI. There was no clear clinical benefit of MSC treatment, but this is not necessarily a proof of inefficacy due to the low number of controlled studies. Future studies assessing efficacy of MSC treatment should aim to do this in randomized, controlled studies.

Tenecteplase versus alteplase for the management of acute ischaemic stroke in Norway (NOR-TEST 2, part A): a phase 3, randomised, open-label, blinded endpoint, non-inferiority trial.

BACKGROUND: Tenecteplase is a modified tissue plasminogen activator with pharmacological and practical advantages over alteplase-which is currently the only approved thrombolytic drug for ischaemic stroke. The NOR-TEST trial showed that 0·4 mg/kg tenecteplase had an efficacy and safety profile similar to that of a standard dose (0·9 mg/kg) of alteplase, albeit in a patient population with a high prevalence of minor stroke. The aim of NOR-TEST 2 was to establish the non-inferiority of tenecteplase 0·4 mg/kg to alteplase 0·9 mg/kg for patients with moderate or severe ischaemic stroke. METHODS: This phase 3, randomised, open-label, blinded endpoint, non-inferiority trial was performed at 11 hospitals with stroke units in Norway. Patients with suspected acute ischaemic stroke with a National Institutes of Health Stroke Scale score of 6 or more who were eligible for thrombolysis and admitted within 4·5 h of symptom onset were consecutively included. Random assignment, done by a computer with a block size of 4 and with allocations placed into opaque envelopes to be opened consecutively, was 1:1 between intravenous tenecteplase (0·4 mg/kg) or standard dose alteplase (0·9 mg/kg). Doctors and nurses providing acute care were not masked to treatment, but primary outcome assessment at 3 months was masked. The primary outcome was favourable functional outcome defined as a modified Rankin Scale score of 0-1 at 3 months, assessed in the modified intention-to-treat analysis (excluding patients who did not qualify for thrombolysis after randomisation or who withdrew informed consent). The non-inferiority margin was 3%. This trial (NOR-TEST 2) is registered with EudraCT (number 2018-003090-95) and ClinicalTrials.gov (NCT03854500). The trial was stopped early for safety reasons and is designated part A for analysis. Part B is ongoing with a lower dose of tenecteplase (0·25 mg/kg). FINDINGS: Between Oct 28, 2019, and Sept 26, 2021, 216 patients were enrolled. Patient enrolment was stopped after a per-protocol safety review showed an imbalance in the rates of symptomatic intracranial haemorrhage between the treatment groups, which surpassed the prespecified criteria for stopping the trial. Of 204 patients entering the modified intention-to-treat analysis, 100 were randomly allocated tenecteplase and 104 were allocated alteplase. All patients were followed up within 14 days of the end of the 3-months' follow-up period. A favourable functional outcome was reported less frequently in patients receiving tenecteplase (31 [32%] of 96 patients) compared with alteplase (52 [51%] of 101 patients; unadjusted OR 0·45 [95% CI 0·25-0·80]; p=0·0064). Any intracranial haemorrhage was significantly more frequent with tenecteplase (21 [21%] of 100 patients) than with alteplase (seven [7%] of 104 patients; unadjusted OR 3·68 [95% CI 1·49-9·11]; p=0·0031). Mortality at 3 months was also significantly higher with tenecteplase (15 [16%] of 96 patients) than with alteplase (five [5%] of 101 patients; unadjusted OR 3·56 [95% CI 1·24-10·21]; p=0·013). Numerically more cases of symptomatic intracranial haemorrhage were reported with tenecteplase (six [6%] of 100 patients) than with alteplase (one [1%] of 104 patients; unadjusted OR 6·57 [95% CI 0·78-55·62]; p=0·061). INTERPRETATION: In this prematurely terminated study (terminated to fulfil the prespecified safety criteria), tenecteplase at a dose of 0·4 mg/kg yielded worse safety and functional outcomes compared with alteplase. Our study consequently could not show that 0·4 mg/kg tenecteplase is non-inferior to alteplase in moderate and severe ischaemic stroke. Future stroke trials should assess a lower dose of tenecteplase versus alteplase in patients with moderate or severe stroke. FUNDING: The Norwegian National Programme for Clinical Therapy Research.

The Course of Carotid Plaque Vulnerability Assessed by Advanced Neurosonology.

Background: Carotid artery atherosclerosis is a major risk factor for ischemic stroke. This risk is related to plaque vulnerability and is characterized by plaque morphology, intraplaque neovascularization, and cerebral microembolization. Advanced neurosonology can identify vulnerable plaques and aid in preventing subsequent stroke. We aimed to assess the time course of cerebral microembolization and intraplaque neovascularization during 6 months of follow-up and to explore the utility of advanced neurosonology in patients with acute cerebral ischemia. Methods: Fifteen patients with acute cerebral ischemia and carotid artery plaques underwent comprehensive extra- and intracranial ultrasound examinations, including microemboli detection and contrast-enhanced ultrasound. The examinations were repeated after 3 and 6 months. Results: We examined 28 plaques in 15 patients. The ultrasonographic features of plaque vulnerability were frequent in symptomatic and asymptomatic plaques. There were no significant differences in stenosis degree, plaque composition, plaque surface, neovascularization, or cerebral microembolization between symptomatic and asymptomatic plaques, but symptomatic plaques had a higher number of vulnerable features. None of the patients had recurrent clinical stroke or transient ischemic attack during the follow-up period. We observed a decrease in cerebral microembolization at 6 months, but no significant change in intraplaque neovascularization. Conclusions: In patients with acute cerebral ischemia and carotid artery plaques, cerebral microembolization decreased during 6 months of follow-up, indicating plaque stabilization. Clinical Trial Registration:ClinicalTrial.gov, identifier NCT02759653.