IC Regimen: Delaying Resistance to Lorlatinib in ALK Driven Cancers by Adding Repurposed Itraconazole and Cilostazol

Lorlatinib is a pharmaceutical ALK kinase inhibitor used to treat ALK driven non-small cell lung cancers. This paper analyses the intersection of past published data on the physiological consequences of two unrelated drugs from general medical practice-itraconazole and cilostazol-with the pathophysiology of ALK positive non-small cell lung cancer. A conclusion from that data analysis is that adding itraconazole and cilostazol may make lorlatinib more effective. Itraconazole, although marketed worldwide as a generic antifungal drug, also inhibits Hedgehog signaling, Wnt signaling, hepatic CYP3A4, and the p-gp efflux pump. Cilostazol, marketed worldwide as a generic thrombosis preventative drug, acts by inhibiting phosphodiesterase 3, and, by so doing, lowers platelets' adhesion, thereby partially depriving malignant cells of the many tumor trophic growth factors supplied by platelets. Itraconazole may enhance lorlatinib effectiveness by (i) reducing or stopping a Hedgehog-ALK amplifying feedback loop, by (ii) increasing lorlatinib's brain levels by p-gp inhibition, and by (iii) inhibiting growth drive from Wnt signaling. Cilostazol, surprisingly, carries minimal bleeding risk, lower than that of aspirin. Risk/benefit assessment of the combination of metastatic ALK positive lung cancer being a low-survival disease with the predicted safety of itraconazole-cilostazol augmentation of lorlatinib favors a trial of this drug trio in ALK positive lung cancer.

European stroke organisation (ESO) guideline on cerebral small vessel disease, part 2, lacunar ischaemic stroke

A quarter of ischaemic strokes are lacunar subtype, typically neurologically mild, usually resulting from intrinsic cerebral small vessel pathology, with risk factor profiles and outcome rates differing from other stroke subtypes. This European Stroke Organisation (ESO) guideline provides evidence-based recommendations to assist with clinical decisions about management of lacunar ischaemic stroke to prevent adverse clinical outcomes. The guideline was developed according to ESO standard operating procedures and Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. We addressed acute treatment (including progressive lacunar stroke) and secondary prevention in lacunar ischaemic stroke, and prioritised the interventions of thrombolysis, antiplatelet drugs, blood pressure lowering, lipid lowering, lifestyle, and other interventions and their potential effects on the clinical outcomes recurrent stroke, dependency, major adverse cardiovascular events, death, cognitive decline, mobility, gait, or mood disorders. We systematically reviewed the literature, assessed the evidence and where feasible formulated evidence-based recommendations, and expert concensus statements. We found little direct evidence, mostly of low quality. We recommend that patients with suspected acute lacunar ischaemic stroke receive intravenous alteplase, antiplatelet drugs and avoid blood pressure lowering according to current acute ischaemic stroke guidelines. For secondary prevention, we recommend single antiplatelet treatment long-term, blood pressure control, and lipid lowering according to current guidelines. We recommend smoking cessation, regular exercise, other healthy lifestyle modifications, and avoid obesity for general health benefits. We cannot make any recommendation concerning progressive stroke or other drugs. Large randomised controlled trials with clinically important endpoints, including cognitive endpoints, are a priority for lacunar ischaemic stroke.

Pathophysiology and probable etiology of cerebral small vessel disease in vascular dementia and Alzheimer's disease

Vascular cognitive impairment and dementia (VCID) is commonly caused by vascular injuries in cerebral large and small vessels and is a key driver of age-related cognitive decline. Severe VCID includes post-stroke dementia, subcortical ischemic vascular dementia, multi-infarct dementia, and mixed dementia. While VCID is acknowledged as the second most common form of dementia after Alzheimer's disease (AD) accounting for 20% of dementia cases, VCID and AD frequently coexist. In VCID, cerebral small vessel disease (cSVD) often affects arterioles, capillaries, and venules, where arteriolosclerosis and cerebral amyloid angiopathy (CAA) are major pathologies. White matter hyperintensities, recent small subcortical infarcts, lacunes of presumed vascular origin, enlarged perivascular space, microbleeds, and brain atrophy are neuroimaging hallmarks of cSVD. The current primary approach to cSVD treatment is to control vascular risk factors such as hypertension, dyslipidemia, diabetes, and smoking. However, causal therapeutic strategies have not been established partly due to the heterogeneous pathogenesis of cSVD. In this review, we summarize the pathophysiology of cSVD and discuss the probable etiological pathways by focusing on hypoperfusion/hypoxia, blood-brain barriers (BBB) dysregulation, brain fluid drainage disturbances, and vascular inflammation to define potential diagnostic and therapeutic targets for cSVD.

Cilostazol Administration for Subarachnoid Hemorrhage: A Meta-analysis of Randomized Controlled Trials

INTRODUCTION

The efficacy of cilostazol administration to treat subarachnoid hemorrhage remains controversial. We conduct a systematic review and meta-analysis to explore the influence of cilostazol administration on treatment efficacy for subarachnoid hemorrhage.

METHODS

We have searched PubMed, Embase, Web of science, EBSCO, and Cochrane Library databases through July 2020 for randomized controlled trials assessing the effect of cilostazol administration in patients with subarachnoid hemorrhage. This meta-analysis is performed using the random-effect model.

RESULTS

Four randomized controlled trials involving 405 patients were included in the meta-analysis. Overall, compared with control group for subarachnoid hemorrhage, cilostazol intervention can significantly reduce symptomatic vasospasm (odds ratio [OR], 0.35; 95% confidence interval [CI], 0.21-0.60; P = 0.0001) and cerebral infarction (OR, 0.40; 95% CI, 0.22-0.73; P = 0.003) and improve no or mild angiographic vasospasm (OR, 2.01; 95% CI, 1.19-3.42; P = 0.01) and an mRS score of 2 or less (OR, 2.70; 95% CI, 1.09-6.71; P = 0.03), but revealed no obvious influence on severe angiographic vasospasm (OR, 0.53; 95% CI, 0.27-1.02; P = 0.06). There were no increase in adverse events (OR, 1.17; 95% CI, 0.54-2.52; P = 0.69), hemorrhagic events (OR, 0.62; 95% CI, 0.06-6.27; P = 0.69), and cardiac events (OR, 2.14; 95% CI, 0.44-10.27; P = 0.34) after the cilostazol intervention than control intervention.

CONCLUSIONS

Cilostazol treatment may be effective to treat subarachnoid hemorrhage in the terms of symptomatic vasospasm, cerebral infarction, no or mild angiographic vasospasm, and an mRS score of 2 or less.

The Efficacy and Safety of Cilostazol vs. Aspirin for Secondary Stroke Prevention: A Systematic Review and Meta-Analysis

Background

Cilostazol is often used in Asia-Pacific countries for stroke prevention. The current systematic review and meta-analysis aimed to evaluate the effectiveness, safety, and adverse outcomes of cilostazol monotherapy compared to aspirin monotherapy for secondary stroke prevention.

Methods

The researchers conducted a comprehensive research in multiple databases (PubMed, Embase, and Cochrane library) of randomized controlled trials from conception to December 2020. The primary efficacy outcome was the occurrence of any stroke, the primary safety outcome was the bleeding risk, and the primary adverse outcome was the rate of headache and dizziness. The Mantel-Haenszel method was used to calculate a random-effects prediction. Cilostazol and aspirin were compared using a pooled risk assessment with 95% CIs.

Results

Six studies involving 5,617 patients were included in this review. Compared with aspirin monotherapy, cilostazol was associated with significantly lower rates of any strokes (RR: 0.67; 95% CI: 0.55–0.82) and significantly lower bleeding rates [risk ratio (RR): 0.53; 95% CI: 0.37–0.74]. However, compared with aspirin monotherapy, cilostazol was associated with significantly higher rates of headache (RR: 1.77; 95% CI: 1.41–2.20) and dizziness (RR: 1.28; 95% CI: 1.08–1.52).

Conclusions

Consistent with previous studies, cilostazol monotherapy is superior to aspirin monotherapy in reducing the rate of any strokes and the bleeding risk after having a stroke. However, the use of cilostazol monotherapy is associated with several adverse life outcomes such as headaches and dizziness.

Recurrent Stroke Incidence and Etiology in Patients with Embolic Stroke of Undetermined Source and Other Stroke Subtypes

AIMS

This study aimed at clarifying the incidence of recurrent stroke and its etiology in patients with embolic stroke of undetermined source (ESUS) and other stroke subtypes in both the acute and chronic periods.

METHODS

A total of 645 patients who were admitted with acute ischemic stroke (IS) between March 2015 and August 2019 were enrolled. Among them, 511 patients with ESUS, cardioembolism (CE), large artery atherosclerosis (LAA), or small vessel disease (SVD) were analyzed in this study. After discharge, 391 patients who visited the outpatient clinic were followed up until August 2020. The outcome was stroke recurrence.

RESULTS

In the acute admission, recurrence rates were 7.6%, 8.1%, 18.8%, and 2.2% in patients with ESUS, CE, LAA, and SVD, respectively, and there were significant differences between the groups. The subtype of recurrence was almost identical to that of the index stroke. In the outpatient clinic, the annual recurrence rates were 4.4%, 4.3%, 6.0%, and 2.9% in ESUS, CE, LAA, and SVD, respectively, and no difference was observed. Subtypes of recurrence in outpatients with ESUS included ESUS, intracerebral hemorrhage (ICH), and SVD. Patients with ESUS and SVD had a higher risk of ICH during follow-up.

CONCLUSIONS

Although the risk of recurrence was comparable between patients with ESUS and CE and intermediate between patients with LAA and SVD, in the acute admission unit, the risk in outpatients was similar among all subtypes. ESUS was the most recurrent stroke subtype in outpatients with ESUS. The risk of hemorrhagic stroke was significant in patients with SVD and ESUS.

Post-stroke treatment with K-134, a phosphodiesterase 3 inhibitor, improves stroke outcomes in the stroke-prone spontaneously hypertensive rat model-A comparative evaluation of antiplatelet drugs

Post-stroke antiplatelet therapy has been proved to reduce the risk of recurrent stroke; however, it may also increase the incidence of intracranial hemorrhage that could offset any benefits. Therefore, the balance between the benefits and risks of antiplatelet drugs is a critical issue to consider. In the present study, we have compared the effects of post-stroke administration of antiplatelet agents on functional outcomes in the stroke-prone spontaneously hypertensive rat (SHRSP), an established animal model that mimics human lacunar stroke and cerebral small vessel disease. We confirmed that a potent phosphodiesterase 3 (PDE3) inhibitor, K-134, significantly improved post-stroke survival rate and survival time, attenuated stroke-induced neurological deficits, and decreased the incidence of cerebral lesion caused by intracerebral hemorrhage and softening. Similarly, cilostazol showed beneficial effects, though to a lower extent with respect to the survival outcome and neurological symptoms. On the other hand, a P2Y12 inhibitor, clopidogrel significantly improved survival outcomes at the higher dose but caused massive bleeding in the brain at both low and high doses. In contrast, no hemorrhagic lesion was observed in K-134-treated SHRSPs despite its antiplatelet activity. Our findings indicate that K-134 may have a superior post-stroke therapeutic outcome in comparison to other antiplatelet drugs.

Update on Cilostazol: A Critical Review of Its Antithrombotic and Cardiovascular Actions and Its Clinical Applications

Cilostazol, a phosphodiesterase III inhibitor, has vasodilating and antiplatelet properties with a low rate of bleeding complications. It has been used over the past 25 years for improving intermittent claudication in patients with peripheral artery disease (PAD). Cilostazol also has demonstrated efficacy in patients undergoing percutaneous revascularization procedures for both PAD and coronary artery disease. In addition to its antithrombotic and vasodilating actions, cilostazol also inhibits vascular smooth muscle cell proliferation via phosphodiesterase III inhibition, thus mitigating restenosis. Accumulated evidence has shown that cilostazol, due to its "pleiotropic" effects, is a useful, albeit underutilized, agent for both coronary artery disease and PAD. It is also potentially useful after ischemic stroke and is an alternative in those who are allergic or intolerant to classical antithrombotic agents (eg, aspirin or clopidogrel). These issues are herein reviewed together with the pharmacology and pharmacodynamics of cilostazol. Large studies and meta-analyses are presented and evaluated. Current guidelines are also discussed, and the spectrum of cilostazol's actions and therapeutic applications are illustrated.

Use of Antiplatelet Agents Decreases the Positive Predictive Value of Fecal Immunochemical Tests for Colorectal Cancer but Does Not Affect Their Sensitivity

Previous studies have evaluated the effects of antithrombotic agents on the performance of fecal immunochemical tests (FITs) for the detection of colorectal cancer (CRC), but the results were inconsistent and based on small sample sizes. We studied this topic using a large-scale population-based database. Using the Korean National Cancer Screening Program Database, we compared the performance of FITs for CRC detection between users and non-users of antiplatelet agents and warfarin. Non-users were matched according to age and sex. Among 5,426,469 eligible participants, 768,733 used antiplatelet agents (mono/dual/triple therapy, n = 701,683/63,211/3839), and 19,569 used warfarin, while 4,638,167 were non-users. Among antiplatelet agents, aspirin, clopidogrel, and cilostazol ranked first, second, and third, respectively, in terms of prescription rates. Users of antiplatelet agents (3.62% vs. 4.45%; relative risk (RR): 0.83; 95% confidence interval (CI): 0.78–0.88), aspirin (3.66% vs. 4.13%; RR: 0.90; 95% CI: 0.83–0.97), and clopidogrel (3.48% vs. 4.88%; RR: 0.72; 95% CI: 0.61–0.86) had lower positive predictive values (PPVs) for CRC detection than non-users. However, there were no significant differences in PPV between cilostazol vs. non-users and warfarin users vs. non-users. For PPV, the RR (users vs. non-users) for antiplatelet monotherapy was 0.86, while the RRs for dual and triple antiplatelet therapies (excluding cilostazol) were 0.67 and 0.22, respectively. For all antithrombotic agents, the sensitivity for CRC detection was not different between users and non-users. Use of antiplatelet agents, except cilostazol, may increase the false positives without improving the sensitivity of FITs for CRC detection.

Cilostazol administration for subarachnoid hemorrhage: A meta-analysis of randomized controlled trials

INTRODUCTION

The efficacy of cilostazol administration to treat subarachnoid hemorrhage remains controversial. We conduct a systematic review and meta-analysis to explore the influence of cilostazol administration on treatment efficacy for subarachnoid hemorrhage.

METHODS

We have searched PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through July 2020 for randomized controlled trials (RCTs) assessing the effect of cilostazol administration in patients with subarachnoid hemorrhage. This meta-analysis is performed using the random-effect model.

RESULTS

Four RCTs involving 405 patients were included in the meta-analysis. Overall, compared with control group for subarachnoid hemorrhage, cilostazol intervention can significantly reduce symptomatic vasospasm (OR = 0.35; 95% CI = 0.21 to 0.60; P = 0.0001) and cerebral infarction (OR = 0.40; 95% CI = 0.22 to 0.73; P = 0.003), as well as improve no or mild angiographic vasospasm (OR = 2.01; 95% CI = 1.19 to 3.42; P = 0.01) and mRS score ≤ 2 (OR = 2.70; 95% CI = 1.09 to 6.71; P = 0.03), but revealed no obvious influence on severe angiographic vasospasm (OR = 0.53; 95% CI = 0.27 to 1.02; P = 0.06). There were no increase in adverse events (OR = 1.17; 95% CI = 0.54 to 2.52; P = 0.69), hemorrhagic events (OR = 0.62; 95% CI = 0.06 to 6.27; P = 0.69) and cardiac events (OR = 2.14; 95% CI = 0.44 to 10.27; P = 0.34) after the cilostazol intervention than control intervention.

CONCLUSIONS

Cilostazol treatment may be effective to treat subarachnoid hemorrhage in the terms of symptomatic vasospasm, cerebral infarction, no or mild angiographic vasospasm and mRS score ≤ 2.

The Impact of Antiplatelet Use on the Risk of Intracerebral Hemorrhage in Patients with Alzheimer's Disease: A Nationwide Cohort Study

BACKGROUND

Antiplatelet use on the risk of intracerebral hemorrhage (ICH) in patients with Alzheimer's disease (AD) has not yet been completely elucidated.

OBJECTIVE

This large epidemiologic study aims to estimate the risk of ICH in AD patients treated with antiplatelet therapy (APT).

METHODS

Using data from Taiwan's National Health Insurance Research Database, ICH risk in APT-treated AD patients with a validated diagnosis (N = 824) was determined. AD without APT and non-AD with and without APT comparison cohorts were selected. To adjust for confounders and competing risk of death, inverse probability of treatment weighting using propensity scores and competing risks regression (CRR) were applied. Cox proportional hazards regression analysis estimated ICH risk in all cohorts comparing with non-AD without APT.

RESULTS

Among the 824 AD patients with APT, 79.6% were prescribed aspirin. ICH incidence rates in the AD (with/without APT) and non-AD (with/without APT) cohorts were 2.88/2.70 and 2.24/1.20 per 1,000 person-years, respectively. Overall, AD with (adjusted hazards ratio (aHR), 2.29; 95% CI, 1.19-4.38) and without (aHR, 1.97; 95% CI, 1.08-3.61) APT and non-AD with APT (aHR, 1.80; 95% CI, 1.34-2.42) were at a higher risk and had elevated subdistribution HR obtained from CRR than non-AD without APT controls. However, the risk was comparable between the AD cohorts with and without APT (HR, 1.16; 95% CI, 0.51-2.66).

CONCLUSIONS

Our study indicated both the APT and non-APT users in AD population yielded higher ICH risks. However, whether APT use potentiate the risk of ICH in AD patients may warrant further evaluation.

Investigation of Blood Pressure Control in Hypertensive Patients with and without Antithrombotic Therapy in a Real-World Setting

Background Although numerous studies have demonstrated a strong association between blood pressure (BP) and hemorrhagic complications of antithrombotic therapy, there is still a paucity of information regarding the status of BP control in hypertensive patients on antithrombotic therapy. Methods This cross-sectional, retrospective study was conducted at an outpatient clinic to examine BP control and its associated factors in hypertensive patients receiving or not receiving antithrombotic therapy. Results Of 26,803 outpatients who had scheduled visits in 2018, 7,800 hypertensive patients met the inclusion criteria, of whom 1,727 cases were on oral antithrombotic drugs. Then, target BP values were defined according to the Japanese Society of Hypertension Guidelines for the Management of Hypertension 2019. While BP values <140/90 mmHg were observed in 63.0% and 61.6% of patients with and without antithrombotic therapy, respectively, only 31.1% and 23.4% of them displayed BP values <130/80 mmHg. Multivariable logistic analysis indicated that comorbidity with obesity was a significant correlate of insufficient BP control (target BP <130/80 mmHg) in hypertensive patients, irrespective of antithrombotic therapy (patients with antithrombotic therapy, odds ratio (OR) = 1.690, 95% confidence interval (CI) = 1.351-2.113; patients without antithrombotic therapy, OR = 1.475, 95% CI = 1.290-1.687). Conclusion The majority of patients exhibited BP values <140/90 mmHg, whereas BP values <130/80 mmHg were achieved only in a small proportion of the patients. Furthermore, obesity appeared to be one of the factors contributing to insufficient BP control in a real-world setting.

Blood Pressure Level and Variability During Long-Term Prasugrel or Clopidogrel Medication After Stroke: PRASTRO-I

BACKGROUND AND PURPOSE

High blood pressure increases bleeding risk during treatment with antithrombotic medication. The association between blood pressure levels and the risk of recurrent stroke during long-term secondary stroke prevention with thienopyridines (particularly prasugrel) has not been well studied.

METHODS

This was a post hoc analysis of the randomized, double-blind, multicenter PRASTRO-I trial (Comparison of Prasugrel and Clopidogrel in Japanese Patients With Ischemic Stroke-I). Patients with noncardioembolic stroke were randomly assigned (1:1) to receive prasugrel 3.75 mg/day or clopidogrel 75 mg/day for 96 to 104 weeks. Risks of any ischemic or hemorrhagic stroke, combined ischemic events, and combined bleeding events were determined based on the mean level and visit-to-visit variability, including successive variation, of systolic blood pressure (SBP) throughout the observational period. These risks were also compared between quartiles of mean SBP level and successive variation of SBP.

RESULTS

A total of 3747 patients (age 62.1±8.5 years, 797 women), with a median average SBP level during the observational period of 132.5 mm Hg, were studied. All the risks of any stroke (146 events; hazard ratio, 1.318 [95% CI, 1.094-1.583] per 10-mm Hg increase), ischemic stroke (133 events, 1.219 [1.010-1.466]), hemorrhagic stroke (13 events, 3.247 [1.660-6.296]), ischemic events (142 events, 1.219 [1.020-1.466]), and bleeding events (47 events, 1.629 [1.172-2.261]) correlated with increasing mean SBP overall. Similarly, an increased risk of these events correlated with increasing successive variation of SBP (hazard ratio, 3.078 [95% CI, 2.220-4.225] per 10-mm Hg increase; 3.051 [2.179-4.262]; 3.276 [1.172-9.092]; 2.865 [2.042-4.011]; 2.764 [1.524-5.016], respectively). Event rates did not differ between the clopidogrel and prasugrel groups within each quartile of SBP or successive variation of SBP.

CONCLUSIONS

Both high mean SBP level and high visit-to-visit variability in SBP were significantly associated with the risk of recurrent stroke during long-term medication with either prasugrel or clopidogrel after stroke. Control of hypertension would be important regardless of the type of antiplatelet drugs. Registration: URL: https://www.clinicaltrials.jp; Unique identifier: JapicCTI-111582.

The Role of Cilostazol and Inflammation in Cognitive Impairment After Ischemic Stroke

PURPOSE

The aim of this study is to examine the potential effect of cilostazol and inflammation on cognitive impairment after stroke in an Asian population.

METHODS

Forty-five patients with cognitive impairment after ischemic stroke using cilostazol were enrolled as the study group and 45 patients using aspirin or clopidogrel were enrolled as the control group. Neuropsychiatric assessments were administered at the start of the study and after 6 months. Multiple logistic regression analysis was used to estimate the association between the cognitive change and cilostazol use. Macrophage polarization were assessed using flow cytometry in 7 patients.

RESULTS

There were a significantly higher number of patients with peripheral arterial occlusive disease in the cilostazol group. No significant differences were observed in the cognitive change between the cilostazol and control groups. M1 macrophage subset increment were observed in the patient having a declined cognitive change.

CONCLUSION

Cilostazol did not make a significant difference in cognitive change after ischemic stroke. M1 macrophage subset increment may indicate post stroke cognitive decline. Due to limited number of subjects, these findings should be examined further in large-scale randomized clinical trials.

Cerebral Microbleeds - To Treat or Not to Treat, That Is the Question: A Case Report With a Note on Its Radiologic Deconstruction and Therapeutic Nuances

With the ubiquity of susceptibility weighted imaging (SWI), cerebral microbleeds (CMBs) are fast becoming a prevalent phenomenon. They are tightly associated with age, neurodegeneration and diverse vascular etiologies. CMBs have a unique radiological signature. Their morphology, number and topology are quite informative. They also pose a therapeutic conundrum, as they are associated with the risk of cerebral hemorrhage. We present the case of an 86-year-old woman who has a vascular dementia, Binswanger's syndrome, and coronary artery disease, who presented with more than five CMBs. We present this case in order to highlight the dilemma of anti-platelet therapy in this group of patients and we demonstrate the cardinal radiologic features of CMBs. We then segue into the pathologic correlates of CMBs and associated risk factors. We finally analyze the risk of anti-platelet therapy in the presence of CMBs, and we unfold the latest data on CMB number and anti-platelet therapy.

Cilostazol versus aspirin in ischemic stroke with cerebral microbleeds versus prior intracerebral hemorrhage

BACKGROUND

In PreventIon of CArdiovascular Events in Ischaemic Stroke Patients with High Risk of Cerebral HaemOrrhage (PICASSO), cilostazol versus aspirin was comparable for the end points of cerebral hemorrhage and major vascular events. However, underlying hemorrhage-prone lesions could modify the treatment effect.

AIMS

We explored whether the safety and efficacy of cilostazol versus aspirin would differ between hemorrhage-prone lesions (multiple cerebral microbleeds vs. prior intracerebral hemorrhage).

METHODS

In this post hoc analysis of PICASSO, we divided patients into the cerebral microbleeds and prior intracerebral hemorrhage subgroups. The primary safety end point was the first occurrence of cerebral hemorrhage. The primary efficacy end point was the composite of stroke, myocardial infarction, or vascular death.

RESULTS

Of 1512 patients, 903 (59.7%) had multiple cerebral microbleeds and 609 (40.3%) had prior intracerebral hemorrhage. The cerebral hemorrhage risk was lower with cilostazol versus aspirin (0.12%/year vs. 1.49%/year; hazard ratio, 0.08 [95% confidence interval 0.01-0.60]; p = 0.015) in the cerebral microbleeds subgroup, but was not different (1.26%/year vs. 0.79%/year; hazards ratio 1.60 [0.52-4.90]; p = 0.408) in the prior intracerebral hemorrhage subgroup. The interaction of treatment-by-subgroup was significant (p_interaction = 0.011). For the composite of major vascular events, there was a trend toward a lower risk with cilostazol versus aspirin (3.56%/year vs. 5.53%/year; hazards ratio 0.64 [0.41-1.01]; p = 0.056) in the cerebral microbleeds subgroup, but was comparable (5.21%/year vs. 5.05%/year; hazards ratio 1.03 [0.63-1.67]; p = 0.913) in the prior intracerebral hemorrhage subgroup without a significant treatment-by-subgroup interaction (p_interaction = 0.165).

CONCLUSIONS

Cilostazol versus aspirin might be a better option in ischemic stroke with multiple cerebral microbleeds, but confirmatory trials are needed.

CLINICAL TRIAL REGISTRATION

URL:http://www.clinicaltrials.gov. NCT01013532.

Cilostazol Versus Aspirin in Ischemic Stroke Patients With High-Risk Cerebral Hemorrhage: Subgroup Analysis of the PICASSO Trial

Background and Purpose- Although cilostazol has shown less hemorrhagic events than aspirin, only marginal difference was observed in hemorrhagic stroke events among patients at high risk for cerebral hemorrhage. To identify patients who would most benefit from cilostazol, this study analyzed interactions between treatment and subgroups of the PICASSO trial (Prevention of Cardiovascular Events in Asian Ischemic Stroke Patients With High Risk of Cerebral Hemorrhage). Methods- Ischemic stroke patients with a previous intracerebral hemorrhage or multiple microbleeds were randomized to treatment with cilostazol or aspirin and followed up for a mean 1.8 years. Efficacy, defined as the composite of any stroke, myocardial infarction, and vascular death, and safety, defined as the incidence of hemorrhagic stroke, were analyzed in the 2 groups. Interactions between treatment and age, sex, presence of hypertension and diabetes mellitus, index of high-risk cerebral hemorrhage, and white matter lesion burden were analyzed for primary and key secondary outcomes. Changes in vital signs and laboratory results were compared in the 2 groups. Results- Among all 1534 patients enrolled, a significant interaction between treatment group and index of high risk for cerebral hemorrhage on hemorrhagic stroke (P for interaction, 0.03) was observed. Hemorrhagic stroke was less frequent in the cilostazol than in the aspirin group in patients with multiple microbleeds (1 versus 13 events; hazard ratio, 0.08 [95% CI, 0.01-0.61]; P=0.01). A marginal interaction between treatment group and white matter change on any stroke (P for interaction, 0.08) was observed. Cilostazol reduced any stroke significantly in patients with mild (5 versus 16 events; hazard ratio, 0.36 [95% CI, 0.13-0.97]; P=0.04)-to-moderate (16 versus 32 events; hazard ratio, 0.50 [95% CI, 0.29-0.92]; P=0.03) white matter changes. Heart rate and HDL (high-density lipoprotein) cholesterol level were significantly higher in the cilostazol group than in the aspirin group at follow-up. Conclusions- Cilostazol may be more beneficial for ischemic stroke patients with multiple cerebral microbleeds and before white matter changes are extensive. Registration- URL: https://www.clinicaltrials.gov. Unique identifier: NCT01013532.

Treatment Approaches to Lacunar Stroke

Lacunar strokes are appropriately named for their ability to cavitate and form ponds or "little lakes" (Latin: lacune -ae meaning pond or pit is a diminutive form of lacus meaning lake). They account for a substantial proportion of both symptomatic and asymptomatic ischemic strokes. In recent years, there have been several advances in the management of large vessel occlusions. New therapies such as non-vitamin K antagonist oral anticoagulants and left atrial appendage closure have recently been developed to improve stroke prevention in atrial fibrillation; however, the treatment of small vessel disease-related strokes lags frustratingly behind. Since Fisher characterized the lacunar syndromes and associated infarcts in the late 1960s, there have been no therapies specifically targeting lacunar stroke. Unfortunately, many therapeutic agents used for the treatment of ischemic stroke in general offer only a modest benefit in reducing recurrent stroke while adding to the risk of intracerebral hemorrhage and systemic bleeding. Escalation of antithrombotic treatments beyond standard single antiplatelet agents has not been effective in long-term lacunar stroke prevention efforts, unequivocally increasing intracerebral hemorrhage risk without providing a significant benefit. In this review, we critically review the available treatments for lacunar stroke based on evidence from clinical trials. For several of the major drugs, we summarize the adverse effects in the context of this unique patient population. We also discuss the role of neuroprotective therapies and neural repair strategies as they may relate to recovery from lacunar stroke.

Progress in the development of antiplatelet agents: Focus on the targeted molecular pathway from bench to clinic

Antiplatelet drugs serve as a first-line antithrombotic therapy for the management of acute ischemic events and the prevention of secondary complications in vascular diseases. Numerous antiplatelet therapies have been developed; however, currently available agents are still associated with inadequate efficacy, risk of bleeding, and variability in individual response. Understanding the mechanisms of platelet involvement in thrombosis and the clinical development process of antiplatelet agents is critical for the discovery of novel agents. The functions of platelets in thrombosis are regulated by two major mechanisms: the interaction between surface receptors and their ligands, and the downstream intracellular signaling pathways. Recently, most of the progress made in antiplatelet drug development has been achieved with P2Y receptor antagonists. Additionally, the usage of GP IIb/IIIa receptor antagonists has decreased, because it is associated with a higher risk of bleeding and thrombocytopenia. Agents targeting other platelet surface receptors such as PARs, TP receptor, EP3 receptor, GPIb-IX-V receptor, P-selectin, as well as intracellular signaling factors, such as PI3Kβ, have been evaluated in an attempt to develop the next generation of antiplatelet drugs, reduce or eliminate interpatient variability of drug efficacy and significantly lower the risk of drug-induced bleeding. The aim of this review is to describe the pathways of platelet activation in thrombosis, and summarize the development process of antiplatelet agents, as well as the preclinical and clinical evaluations performed on these agents.

Pharmacological Potential of Cilostazol for Alzheimer's Disease

Alzheimer’s disease (AD), a slow progressive form of dementia, is clinically characterized by cognitive dysfunction and memory impairment and neuropathologically characterized by the accumulation of extracellular plaques containing amyloid β-protein (Aβ) and neurofibrillary tangles containing tau in the brain, with neuronal degeneration and high level of oxidative stress. The current treatments for AD, e.g., acetylcholinesterase inhibitors (AChEIs), have efficacies limited to symptom improvement. Although there are various approaches to the disease modifying therapies of AD, none of them can be used alone for actual treatment, and combination therapy may be needed for amelioration of the progression. There are reports that cilostazol (CSZ) suppressed cognitive decline progression in patients with mild cognitive impairment or stable AD receiving AChEIs. Previously, we showed that CSZ suppressed Aβ-induced neurotoxicity in SH-SY5Y cells via coincident inhibition of oxidative stress, as demonstrated by reduced activity of nicotinamide adenine dinucleotide phosphate oxidase, accumulation of reactive oxygen species, and signaling of mitogen-activated protein kinase. CSZ also rescued cognitive impairment and promoted soluble Aβ clearance in a mouse model of cerebral amyloid angiopathy. Mature Aβ fibrils have long been considered the primary neurodegenerative factors in AD; however, recent evidence indicates soluble oligomers to initiate the neuronal and synaptic dysfunction related to AD and other protein-misfolding diseases. Further underscoring the potential of CSZ for AD treatment, we recently described the inhibitory effects of CSZ on Aβ oligomerization and aggregation in vitro. In this review, we discuss the possibility of CSZ as a potential disease-modifying therapy for the prevention or delay of AD.

Periprocedural Neuroendovascular Antiplatelet Strategies for Thrombosis Prevention in Clopidogrel-Hyporesponsive Patients

Patients undergoing neuroendovascular procedures such as cerebral aneurysm coiling and intracranial stent deployment are frequently treated with antiplatelet agents to prevent thrombotic complications. The combination of aspirin and a P2Y12 inhibitor such as clopidogrel is often initiated days before elective procedures or as loading doses for emergent procedures; however, some patients may still experience thrombotic complications. Patients identified as clopidogrel hyporesponders are more likely to experience poor outcomes and may require changes to their regimens. Historically, high-dose clopidogrel regimens were used in response to subtherapeutic results of platelet function assays and point-of-care testing despite limited supporting data. Recently, more data have emerged using alternative P2Y12 inhibitors such as prasugrel and ticagrelor. Dosing for neuroendovascular conditions is often extrapolated from the cardiac literature, although outcomes in cardiac patients may not be relevant to neurologic patients, making prophylactic treatment recommendations challenging for these patients. This review summarizes the literature for antiplatelet prophylaxis in patients undergoing neuroendovascular device placement, focusing on alternative regimens for clopidogrel hyporesponders.

The safety of triple antiplatelet therapy under thromboelastography guidance in patients undergoing stenting for ischemic cerebrovascular disease

OBJECTIVE

To investigate the safety of triple antiplatelet therapy (TAT) with cilostazol in patients undergoing stenting for extracranial and/or intracranial artery stenosis.

METHODS

A prospectively collected database was reviewed to identify patients who underwent stenting for extracranial and/or intracranial artery stenosis and showed resistance to aspirin and/or clopidogrel as assessed by pre-stenting thromboelastography (TEG) testing. Patients were assigned to a TAT group and a dual antiplatelet therapy (DAT) group. Major complications were defined as thromboembolic events (transient ischemic attack (TIA), ischemic stroke, and stent thrombosis) or major bleeding events within 30 days, and minor complications were defined as extracranial bleeding that did not require vascular surgery or transfusion within 30 days.

RESULTS

A total of 183 patients were identified. The incidence of major complications was significantly lower in the TAT group than in the DAT group (TAT group vs. DAT group, 1/110 vs. 6/73; P=0.017). TIAs occurred in four patients, with one in the TAT group and three in the DAT group (1/110 vs. 3/73; P=0.303). Ischemic strokes occurred in three patients in the DAT group (TAT group vs. DAT group, P=0.062). No major bleeding events or stent thrombosis was recorded in either group. Two patients (one in each group) experienced minor complications that resolved without additional treatment (1/110 vs. 1/73; P>0.999).

CONCLUSIONS

TAT under TEG guidance appears to be a safe antiplatelet strategy in patients undergoing stenting for extracranial and/or intracranial artery stenosis. By employing TAT under TEG guidance, favorable outcomes can be achieved in these patients.

Updates on Prevention of Hemorrhagic and Lacunar Strokes

Intracerebral hemorrhage (ICH) and lacunar infarction (LI) are the major acute clinical manifestations of cerebral small vessel diseases (cSVDs). Hypertensive small vessel disease, cerebral amyloid angiopathy, and hereditary causes, such as Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy (CADASIL), constitute the three common cSVD categories. Diagnosing the underlying vascular pathology in these patients is important because the risk and types of recurrent strokes show significant differences. Recent advances in our understanding of the cSVD-related radiological markers have improved our ability to stratify ICH risk in individual patients, which helps guide antithrombotic decisions. There are general good-practice measures for stroke prevention in patients with cSVD, such as optimal blood pressure and glycemic control, while individualized measures tailored for particular patients are often needed. Antithrombotic combinations and anticoagulants should be avoided in cSVD treatment, as they increase the risk of potentially fatal ICH without necessarily lowering LI risk in these patients. Even when indicated for a concurrent pathology, such as nonvalvular atrial fibrillation, nonpharmacological approaches should be considered in the presence of cSVD. More data are emerging regarding the presentation, clinical course, and diagnostic markers of hereditary cSVD, allowing accurate diagnosis, and therefore, guiding management of symptomatic patients. When suspicion for asymptomatic hereditary cSVD exists, the pros and cons of prescribing genetic testing should be discussed in detail in the absence of any curative treatment. Recent data regarding diagnosis, risk stratification, and specific preventive approaches for both sporadic and hereditary cSVDs are discussed in this review article.

Discordant lumbar epidural hematoma after caudal steroid injection: A case report (CARE-compliant)

RATIONALE

Caudal epidural injection is one of the conventional treatments of chronic back pain. Even though spinal epidural hematoma after caudal epidural injection is rare but it can cause serious neurologic complication.

PATIENT CONCERNS

An 83-year-old woman taking cilostazol received caudal epidural steroid injection because of her chronic back pain. Six hours later, she experienced an acute hip pain which worsened with time.

DIAGNOSIS

Magnetic resonance image showed acute cord compression due to a spinal epidural hematoma at L2-S1 level with concomitant central canal compromise at L2/3, L3/4 level.

INTERVENTIONS

Emergency decompressive laminectomy and evacuation of the lumbar epidural hematoma were performed.

OUTCOMES

All of her symptoms were resolved over the 72 hours following surgery.

LESSONS

Continuous vigilance after caudal epidural injection is important to prevent catastrophic neurologic deterioration with early detection and early treatment.

Comparative efficacy and safety of antiplatelet agents in cerebral ischemic disease: A network meta-analysis

We performed a network meta-analysis (NMA) to enhance the corresponding evidence of the relative efficacy and safety of different antiplatelet agents in cerebral ischemic disease. PubMed and EMBASE were searched systematically for relevant studies. Outcomes were compared using odds ratios and 95% credible intervals. Each agent was ranked according to the value of surface under the cumulative ranking curve (SUCRA). Publication bias was evaluated by funnel plots, while consistency between direct and indirect comparison was analyzed by node-splitting and heat plots. Besides, the clustering technique was used to categorize similar agents. A number of 44 eligible studies with 148 578 patients were included in this NMA. In terms of efficacy (including mortality, recurrent stroke, and vascular event), all six interventions were better than placebo. clopidogrel (Clop) and aspirin (ASA)+Clop were the best two interventions from SUCRA. However, the performance of ASA+Clop declined significantly when considering safety (including myocardial infarction, all-cause withdrawal, and intracranial hemorrhage), especially worse in intracranial hemorrhage. In conclusion, Clop was potentially the most preferable treatment for preventing cerebral ischemic in terms of efficacy and safety. However, the addition of ASA was associated with a potential increase in intracranial hemorrhage, therefore, combination therapy of ASA and Clop should be introduced with caution although it may be more effective than the monotherapy of ASA.

A multicenter, randomized, placebo-controlled trial for cilostazol in patients with mild cognitive impairment: The COMCID study protocol

Introduction

There are currently no effective treatments preventing conversion from mild cognitive impairment (MCI) to Alzheimer's disease. Cilostazol is a selective type-3 phosphodiesterase inhibitor that ameliorates accumulation of amyloid-β and has prevented cognitive decline in rodent models. Furthermore, cilostazol is known to suppress platelet aggregation, protect vascular endothelia, dilate vessels, and increase cerebral blood flow. Beneficial effects have also been shown in observational cohort studies, demonstrating the need for a prospective clinical trial.

Methods

The Cilostazol for prevention of COnversion from MCI to Dementia (COMCID) study is a double-blind, randomized phase II study of patients with MCI. Participants will receive cilostazol or placebo for 96 weeks. The primary objective is to evaluate whether cilostazol slows down cognitive decline measured by the Mini-Mental State Examination. Secondary objectives are assessing time to conversion from MCI to dementia and assessing incremental changes in several psychological assessment scales.

Discussion

The COMCID trial will identify the therapeutic potential of cilostazol. This trial, which is based on a drug repositioning strategy, may aid the development of a neurovascular treatment for neurocognitive disorders.

Cilostazol research in Asia: can it be applied to European and American patients?

Cilostazol is an antiplatelet drug often used in Asian countries like Korea, Japan, and China. However, it is rarely used in the west. Cilostazol inhibits phosphodiesterase, increases cyclic AMP concentrations, and consequently inhibits platelet aggregation. Interestingly, it also has vasodilatory activity, inhibits vascular smooth muscle proliferation, and protects the endothelium. Studies in Asia have shown that cilostazol is effective in the secondary prevention of stroke. Moreover, it is significantly less likely to cause bleeding complications than aspirin. Additional trials have shown that cilostazol is effective in the prevention of intracranial atherosclerosis progression. Unfortunately, cilostazol has rarely been studied in non-Asian stroke patients and, accordingly, the benefits of cilostazol are less well appreciated in Europe and America than in Asia. Although further studies are required, we suggest that at least some stroke patients (e.g., patients prone to bleeding, patients with intracranial atherosclerosis, etc.) may readily benefit from cilostazol regardless of ethnicity.

Characteristics of Symptomatic Intracranial Hemorrhage in Patients Receiving Non-Vitamin K Antagonist Oral Anticoagulant Therapy

Objectives

The first non-vitamin K antagonist oral anticoagulant (NOAC) introduced to the market in Japan was dabigatran in March 2011, and three more NOACs, rivaroxaban, apixaban, and edoxaban, have since become available. Randomized controlled trials of NOACs have revealed that intracranial hemorrhage (ICH) occurs less frequently with NOACs compared with warfarin. However, the absolute incidence of ICH associated with NOACs has increased with greater use of these anticoagulants, and we wanted to explore the incidence, clinical characteristics, and treatment course of patients with NOACs-associated ICH.

Methods

We retrospectively analyzed the characteristics of symptomatic ICH patients receiving NOACs between March 2011 and September 2014.

Results

ICH occurred in 6 patients (5 men, 1 woman; mean ± SD age, 72.8 ± 3.2 years). Mean time to onset was 146.2 ± 111.5 days after starting NOACs. Five patients received rivaroxaban and 1 patient received apixaban. None received dabigatran or edoxaban. Notably, no hematoma expansion was observed within 24 h of onset in the absence of infusion of fresh frozen plasma, activated prothrombin complex concentrate, recombinant activated factor VIIa or hemodialysis. When NOAC therapy was initiated, mean HAS-BLED and PANWARDS scores were 1.5 ± 0.5 and 39.5 ± 7.7, respectively. Mean systolic blood pressure was 137.8 ± 15.9 mmHg within 1 month before spontaneous ICH onset.

Conclusion

Six symptomatic ICHs occurred early in NOAC therapy but hematoma volume was small and did not expand in the absence of infusion of reversal agents or hemodialysis. The occurrence of ICH during NOAC therapy is possible even when there is acceptable mean systolic blood pressure control (137.8 ± 15.9 mmHg) and HAS-BLED score ≤ 2. Even stricter blood pressure lowering and control within the acceptable range may be advisable to prevent ICH during NOAC therapy.

New developments in the pharmacological treatment of hypertension: dead-end or a glimmer at the horizon?

Arterial hypertension is the most prevalent controllable disease world-wide. Yet, we still need to further improve blood pressure control, deal with resistant hypertension, and we hope to reduce risk "beyond blood pressure." The number of candidate molecules aspiring for these aims is constantly declining. The new possible approaches to combat high blood pressure include neprilysin/neutral endopeptidase (NEP) inhibition, particularly when combined with an angiotensin receptor blockade (such as the ARNI, LCZ696), phosphodiesterase 5 (PDE5) inhibition (KD027/Slx-2101), natriuretic agents (PL3994), or a long-lasting vasointestinal peptide (VIP) analogue (PB1046). Other options exploit the protective arm of the renin-angiotensin-aldosterone system by stimulating the angiotensin AT2 receptor (compound 21), the Mas receptor (AVE-0991), or the angiotensin converting enzyme 2. Finally, we review the possibilities how to optimize the use of the available treatment options by using drug combinations or by tailoring therapy to each patient's angiotensin peptide profile.

Prevention and Management of Cerebral Small Vessel Disease

Lacunar infarcts/lacunes, white matter hyperintensities (WMH), and cerebral microbleeds (CMBs) are considered various manifestations of cerebral small vessel disease (SVD). Since the exact mechanisms of these manifestations differ, their associated risk factors differ. High blood pressure is the most consistent risk factor for all of these manifestations. However, a "J curve" phenomenon in terms of blood pressure probably exists for WMH. The association between cholesterol levels and lacunar infarcts/lacunes or WMH was less consistent and sometimes conflicting; a low cholesterol level probably increases the risk of CMBs. Homocysteinemia appears to be associated with WMH. It is noteworthy that the risk factors profile may also differ between different lacunar patterns and CMBs located at different parts of the brain. Thrombolysis, antihypertensives, and statins are used to treat patients with symptomatic lacunar infarction, just as in those with other stroke subtypes. However, it should be remembered that bleeding risks increase in patients with extensive WMH and CMBs after thrombolysis therapy. According to the Secondary Prevention of Small Subcortical Strokes trial results, a blood pressure reduction to <130 mmHg is recommended in patients with symptomatic lacunar infarction. However, an excessive blood pressure decrease may induce cognitive decline in older patients with extensive WMH. Dual antiplatelet therapy (aspirin plus clopidogrel) should be avoided because of the excessive risk of intracerebral hemorrhage. Although no particular antiplatelet is recommended, drugs such as cilostazol or triflusal may have advantages for patients with SVD since they are associated with less frequent bleeding complications than aspirin.

Prospective analysis of risk for bleeding after endoscopic biopsy without cessation of antithrombotics in Japan

BACKGROUND AND AIM

In Japan, after the revision of the gastrointestinal endoscopic guidelines for patients taking antithrombotics, endoscopic biopsies were permitted while continuing antithrombotic treatment. However, the risk of bleeding after the biopsy with or without cessation of antithrombotics has not been fully evaluated because bleeding events are very rare. The aim of this prospective study was to evaluate the risk for bleeding after upper gastrointestinal biopsy without cessation of antithrombotics.

METHODS

Consecutive patients who underwent upper gastrointestinal endoscopic biopsy from December 2011 to March 2014 were enrolled in this study. Antithrombotic medication and its cessation status was checked at enrollment. To confirm bleeding events associated with biopsy, medical examination at the hospital or direct confirmation by telephone was done within 1 month after the biopsy.

RESULTS

Among the 3758 patients who underwent endoscopic biopsies, 394 patients (10.5%) were medicated with antithrombotics, and 286 of them (72.6% of the total antithrombotics users) did not undergo cessation. Bleeding after the biopsy occurred in six cases (0.15%, 95% CI; 0.09%∼0.22%), but there was only one case that had continued taking antithrombotics. The incidence of bleeding after biopsy was not significantly higher in the patients who had continued taking antithrombotics compared with the others (0.35% vs 0.14%, P = 0.38).

CONCLUSION

This prospective study showed that continuation of antithrombotics did not increase the bleeding risk after upper gastrointestinal endoscopic biopsy.

Cilostazol: an antiplatelet agent for the neurointerventionist?

Antiplatelet agents are essential for the successful management of patients undergoing a variety of neurointerventional procedures. The most commonly used anti-platelet agents are aspirin, clopidogrel and prasugrel. However, there exist an alternative class of anti-platelet agent that may prove useful for neurointerventionists. In particular a drug called cilostazol may have numerous added advantages above and beyond its antiplatelet effect that may be valuable for our patients. In this short review we aim to highlight some of these potential advantages.

New therapeutic approaches for Alzheimer's disease and cerebral amyloid angiopathy

Accumulating evidence has shown a strong relationship between Alzheimer’s disease (AD), cerebral amyloid angiopathy (CAA), and cerebrovascular disease. Cognitive impairment in AD patients can result from cortical microinfarcts associated with CAA, as well as the synaptic and neuronal disturbances caused by cerebral accumulations of β-amyloid (Aβ) and tau proteins. The pathophysiology of AD may lead to a toxic chain of events consisting of Aβ overproduction, impaired Aβ clearance, and brain ischemia. Insufficient removal of Aβ leads to development of CAA and plays a crucial role in sporadic AD cases, implicating promotion of Aβ clearance as an important therapeutic strategy. Aβ is mainly eliminated by three mechanisms: (1) enzymatic/glial degradation, (2) transcytotic delivery, and (3) perivascular drainage (3-“d” mechanisms). Enzymatic degradation may be facilitated by activation of Aβ-degrading enzymes such as neprilysin, angiotensin-converting enzyme, and insulin-degrading enzyme. Transcytotic delivery can be promoted by inhibition of the receptor for advanced glycation end products (RAGE), which mediates transcytotic influx of circulating Aβ into brain. Successful use of the RAGE inhibitor TTP488 in Phase II testing has led to a Phase III clinical trial for AD patients. The perivascular drainage system seems to be driven by motive force generated by cerebral arterial pulsations, suggesting that vasoactive drugs can facilitate Aβ clearance. One of the drugs promoting this system is cilostazol, a selective inhibitor of type 3 phosphodiesterase. The clearance of fluorescent soluble Aβ tracers was significantly enhanced in cilostazol-treated CAA model mice. Given that the balance between Aβ synthesis and clearance determines brain Aβ accumulation, and that Aβ is cleared by several pathways stated above, multi-drugs combination therapy could provide a mainstream cure for sporadic AD.