Ischemic stroke is a life-threatening cerebral vascular disease and accounts for high disability and mortality worldwide. Currently, no efficient therapeutic strategies are available for promoting neurological recovery in clinical practice, except rehabilitation. The majority of neuroprotective drugs showed positive impact in pre-clinical studies but failed in clinical trials. Therefore, there is an urgent demand for new promising therapeutic approaches for ischemic stroke treatment. Emerging evidence suggests that exosomes mediate communication between cells in both physiological and pathological conditions. Exosomes have received extensive attention for therapy following a stroke, because of their unique characteristics, such as the ability to cross the blood brain–barrier, low immunogenicity, and low toxicity. An increasing number of studies have demonstrated positively neurorestorative effects of exosome-based therapy, which are largely mediated by the microRNA cargo. Herein, we review the current knowledge of exosomes, the relationships between exosomes and stroke, and the therapeutic effects of exosome-based treatments in neurovascular remodeling processes after stroke. Exosomes provide a viable and prospective treatment strategy for ischemic stroke patients.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease partly caused by gain-of-function mutations in superoxide dismutase 1 (SOD1). Here we developed RAG-17, an siRNA-targeting SOD1, using an accessory oligonucleotide conjugate platform for enhanced central nervous system (CNS) delivery. Preclinically, RAG-17 rescued motor neuron degeneration, delayed disease progression, preserved motor function and extended survival in SOD1^G93A ALS rodents, even with advanced-stage treatment. In cynomolgus monkeys, intrathecal RAG-17 led to dose-dependent, durable reductions in SOD1 mRNA (CNS) and protein (cerebrospinal fluid (CSF)). In a first-in-human trial in patients with SOD1-ALS (n = 6), participants were assigned to two cohorts-cohort 1 (n = 3) received an initial 60 mg dose (seven doses total) and cohort 2 (n = 3) received an initial 90 mg dose (six doses total). The dose was escalated in 30 mg steps to maintenance doses of 150 mg (n = 5) or 180 mg (n = 1). Thus, the primary safety endpoint was met, showing acceptable safety and tolerability. Treatment-emergent adverse events (TEAEs) occurred in 33% of participants (two of six). All TEAEs were mild to moderate, including muscle tremor (two patients) and elevated alanine aminotransferase (one patient), all of which resolved. No serious adverse events were reported. Furthermore, no other clinically meaningful changes were observed in laboratory parameters, vital signs, the ALS Functional Rating Scale-Revised score, physical or neurological examinations or ECG. The key secondary endpoints showed CSF SOD1 reductions of 69% (cohort 1, day 240) and 56% (cohort 2, day 210), and plasma neurofilament light chain reductions of 62% (cohort 1) and 52% (cohort 2), from baseline; no patient required invasive mechanical ventilation or died by the end of the study. These results demonstrate a favorable safety outcome, supporting the continued clinical evaluation of RAG-17 for SOD1-ALS. ClinicalTrials.gov registration: NCT05903690 .

BACKGROUND: The aim of this study was to investigate the clinical outcomes of clopidogrel-aspirin therapy initiated between 24 and 72 hours from the symptom onset among patients with minor stroke or transient ischemic attack stratified by CYP2C19 loss-of-function allele status. METHODS: This was a prespecified secondary analysis of the INSPIRES trial (Intensive Statin and Antiplatelet Therapy for Acute High-Risk Intracranial or Extracranial Atherosclerosis), which was a randomized clinical trial conducted across 222 centers in China from September 2018 to October 2022. Two loss-of-function alleles ( CYP2C19*2 , CYP2C19*3 ) and 1 gain-of-function allele ( CYP2C19*17 ) were genotyped in the INSPIRES study. Patients with CYP2C19 loss-of-function allele carriers were patients with either CYP2C19*2 or CYP2C19*3 . All participants were randomized to receive clopidogrel-aspirin or aspirin treatment, and those started treatment between 24 and 72 hours from the symptom onset were included in this study. The primary efficacy outcome was new stroke within 90 days. The primary safety outcome was moderate-to-severe bleeding. Cox proportional hazards models were performed to estimate the interaction between treatment assignment and CYP2C19 loss-of-function allele status for the primary outcomes. RESULTS: Among 5003 patients, 2911 (58.2%) patients were loss-of-function carriers, and 2092 (41.8%) patients were noncarriers. Relative to aspirin alone, clopidogrel-aspirin reduced the rate of new stroke in the noncarriers (hazard ratio, 0.67 [95% CI, 0.49–0.91]; P =0.01) but not in the carriers (hazard ratio, 0.96 [95% CI, 0.73–1.25], P =0.74; P =0.09 for interaction). For the safety outcome, moderate-to-severe bleeding did not vary significantly between the carriers (hazard ratio, 1.83 [95% CI, 0.68–4.95]; P =0.23) and noncarriers (hazard ratio, 2.07 [95% CI, 0.62–6.88], P =0.23; P =0.88 for interaction). CONCLUSIONS: Clopidogrel-aspirin treatment presented a priority to aspirin in reducing the risk of new stroke in CYP2C1 9 loss-of-function noncarriers when administered between 24 and 72 hours after stroke onset. These findings supported the necessity of CYP2C19 genotyping in the choice of antiplatelet therapy with an extended treatment window to 72 hours. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03635749.

In this study, we explored the relationship between the platelet endothelial aggregation receptor 1 (PEAR1) polymorphisms, platelet reactivity, and clinical outcomes in patients with minor stroke or transient ischemic attack (TIA). Randomized controlled trial subgroups were assessed, wherein patients received dual antiplatelet therapy for at least 21 days. Platelet reactivity was measured at different time intervals. Genotypes were categorized as wild-type, mutant heterozygous, and mutant homozygous. Clinical outcomes were evaluated after 90 days. The rs12041331 polymorphism predominantly influenced adenosine diphosphate channel platelet activity, with the AA genotype displaying significantly lower residual platelet activity to the P2Y12 response unit (p < 0.01). This effect was more evident after 7 days of dual antiplatelet treatment (p = 0.016). Mutant A allele carriers had decreased rates of recurrent stroke and complex endpoint events but were more prone to bleeding (p = 0.015). The rs2768759 polymorphism majorly impacted arachidonic acid (AA) channel platelet activity, which was particularly noticeable in the C allele carriers. Our regression analysis demonstrated that rs12041331 AA + GA and rs2768759 CA predicted 90-day post-stroke bleeding. In conclusion, the PEAR1 polymorphisms rs12041331 and rs2768759 interfere with platelet aggregation and the performance of antiplatelet drugs. These genetic variations may contribute to bleeding events associated with minor stroke and TIA.

Previous studies have shown a beneficial effect of clopidogrel-aspirin and intensive statin therapy in acute ischemic stroke; however, the synergistic effect of the 2 treatments is still unclear. The aim of this study was to investigate the effect of combining clopidogrel-aspirin and immediate intensive statin in patients with acute mild ischemic stroke or transient ischemic attack (TIA). We performed a multicenter, randomized, double-blind, placebo-controlled trial with a 2-by-2 factorial design across 222 hospitals in China. Eligible participants were patients with acute mild ischemic stroke or TIA of a presumed atherosclerotic cause within 72 hours of symptom onset. Patients were randomly assigned to receive clopidogrel plus aspirin or aspirin alone and an immediate or delayed intensive statin. The primary efficacy outcome was a new stroke (ischemic or hemorrhagic) within 90 days, and the primary safety outcome was moderate-to-severe bleeding. Between September 17, 2018, and October 15, 2022, 6,100 patients were enrolled (median age, 65 years; 64.2% male), of whom 1,525 each were assigned to the 4 groups. New stroke within 90 days occurred in 116 patients (7.6%) in the clopidogrel-aspirin plus immediate intensive statin group (hazard ratio [HR] 0.76, 95% CI 0.60-0.97), in 106 patients (7.0%) in the clopidogrel-aspirin plus delayed statin group (HR 0.69, 95% Cl 0.54-0.89), and in 129 patients (8.5%) in the aspirin plus immediate statin group (HR 0.85, 95% Cl 0.67 to 1.07), compared with 150 patients (9.9%) in the aspirin plus delayed intensive statin group. Moderate-to-severe bleeding occurred in 17 (1.1%) in the clopidogrel-aspirin plus immediate statin group (p = 0.047), 10 (0.7%) in the clopidogrel-aspirin plus delayed statin group (p = 0.46), and 6 (0.4%) in the aspirin plus immediate statin group (p = 0.80), compared with 7 (0.5%) in the aspirin plus delayed statin group. Among patients with mild ischemic stroke or TIA of presumed atherosclerotic cause, the combination of clopidogrel-aspirin and delayed intensive statin was superior to aspirin plus delayed intensive statin in reducing the risk of new stroke, an effect that was mainly driven by clopidogrel-aspirin and not significantly different from that of clopidogrel-aspirin plus immediate statin. The combination treatment had a low but increased risk of moderate-to-severe bleeding. ClinicalTrials.gov identifier: NCT03635749. This study provides Class I evidence that in patients with mild ischemic stroke or TIA of presumed atherosclerotic cause, the combination of clopidogrel-aspirin plus delayed intensive statin was superior to aspirin plus delayed intensive statin in reducing the 90-day risk of new stroke.

BACKGROUND: The aim of this study was to investigate the association between PAR-1 (protease-activated receptor-1) gene F2R polymorphisms and the efficacy of clopidogrel therapy initiated within a time window extended to 72 hours for mild ischemic stroke or transient ischemic attack with intracranial or extracranial atherosclerosis. METHODS: This was a secondary analysis of the INSPIRES trial (Intensive Statin and Antiplatelet Therapy for Acute High-Risk Intracranial or Extracranial Atherosclerosis), a randomized clinical trial conducted at 222 centers across China between September 2018 and October 2022. Four single-nucleotide polymorphisms ( F2R [IVSn-14 A/T, rs168753], CYP2C19*2 [681G>A, rs4244285], CYP2C19*3 [636G>A, rs4986893], and CYP2C19*17 [−806C>T, rs12248560]) were genotyped among 5791 patients treated with clopidogrel plus aspirin (n=2894) or aspirin alone (n=2897). The primary efficacy outcome was new stroke, and the safety outcome was moderate-to-severe bleeding within 90 days. Cox proportional hazards models were used to estimate the interaction between treatment assignment and F2R polymorphisms for the primary outcomes. RESULTS: Among 5791 patients, 1698 (29.3%) were AA homozygotes, and 4093 (70.7%) were the T-allele carriers (AT/TT) for F2R IVSn-14 polymorphisms. Compared with aspirin alone, clopidogrel-aspirin reduced the rate of new stroke in patients with AT/TT genotype (7.1% versus 9.2%; hazard ratio [HR], 0.77 [95% CI, 0.62–0.95]; P =0.02) but not in carriers of the AA genotype (7.7% versus 8.1%; HR, 0.95 [95% CI, 0.67–1.33]; P =0.75; P =0.30 for interaction). For the safety outcome, the risk of moderate-to-severe bleeding between the clopidogrel plus aspirin group and aspirin group was not significant in patients with AT/TT genotype (HR, 1.91 [95% CI, 0.85–4.29]; P =0.12) or AA genotype (HR, 1.97 [95% CI, 0.59–6.55]; P =0.27; P =0.97 for interaction). Moreover, the presence of CYP2C19 loss-of-function allele carrier status did not alter the effect of the F2R polymorphisms on clinical outcomes, although a marginally reduced risk of stroke with clopidogrel-aspirin versus aspirin alone was observed only among carriers of at least 1 F2R IVSn-14 T allele without CYP2C19 loss-of-function allele (HR, 0.73 [95% CI, 0.52–1.01]; P =0.06). CONCLUSIONS: With the treatment initiated within a time window extended to 72 hours after mild ischemic stroke or transient ischemic attack onset, we found that clopidogrel plus aspirin may reduce the occurrence of new stroke specifically in F2R IVSn-14 T-allele carriers. This finding suggests that the clopidogrel-aspirin treatment may appear more beneficial among carriers of the F2R IVSn-14 T allele. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03635749.