Cerebrovascular Effects of Sildenafil in Small Vessel Disease: The OxHARP Trial.

BACKGROUND: Vascular cognitive impairment due to cerebral small vessel disease is associated with cerebral pulsatility, white matter hypoperfusion, and reduced cerebrovascular reactivity (CVR), and is potentially improved by endothelium-targeted drugs such as cilostazol. Whether sildenafil, a phosphodiesterase-5 inhibitor, improves cerebrovascular dysfunction is unknown. METHODS: OxHARP trial (Oxford Haemodynamic Adaptation to Reduce Pulsatility) was a double-blind, randomized, placebo-controlled, 3-way crossover trial after nonembolic cerebrovascular events with mild-moderate white matter hyperintensities (WMH), the most prevalent manifestation of cerebral small vessel disease. The primary outcome assessed the superiority of 3 weeks of sildenafil 50 mg thrice daily versus placebo (mixed-effect linear models) on middle cerebral artery pulsatility, derived from peak systolic and end-diastolic velocities (transcranial ultrasound), with noninferiority to cilostazol 100 mg twice daily. Secondary end points included the following: cerebrovascular reactivity during inhalation of air, 4% and 6% CO2 on transcranial ultrasound (transcranial ultrasound-CVR); blood oxygen-level dependent-magnetic resonance imaging within WMH (CVR-WMH) and normal-appearing white matter (CVR-normal-appearing white matter); cerebral perfusion by arterial spin labeling (magnetic resonance imaging pseudocontinuous arterial spin labeling); and resistance by cerebrovascular conductance. Adverse effects were compared by Cochran Q. RESULTS: In 65/75 (87%) patients (median, 70 years;79% male) with valid primary outcome data, cerebral pulsatility was unchanged on sildenafil versus placebo (0.02, -0.01 to 0.05; P=0.18), or versus cilostazol (-0.01, -0.04 to 0.02; P=0.36), despite increased blood flow (∆ peak systolic velocity, 6.3 cm/s, 3.5-9.07; P<0.001; ∆ end-diastolic velocity, 1.98, 0.66-3.29; P=0.004). Secondary outcomes improved on sildenafil versus placebo for CVR-transcranial ultrasound (0.83 cm/s per mm Hg, 0.23-1.42; P=0.007), CVR-WMH (0.07, 0-0.14; P=0.043), CVR-normal-appearing white matter (0.06, 0.00-0.12; P=0.048), perfusion (WMH: 1.82 mL/100 g per minute, 0.5-3.15; P=0.008; and normal-appearing white matter, 2.12, 0.66-3.6; P=0.006) and cerebrovascular resistance (sildenafil-placebo: 0.08, 0.05-0.10; P=4.9×10-8; cilostazol-placebo, 0.06, 0.03-0.09; P=5.1×10-5). Both drugs increased headaches (P=1.1×10-4), while cilostazol increased moderate-severe diarrhea (P=0.013). CONCLUSIONS: Sildenafil did not reduce pulsatility but increased cerebrovascular reactivity and perfusion. Sildenafil merits further study to determine whether it prevents the clinical sequelae of small vessel disease. REGISTRATION: URL: https://www.clinicaltrials.gov/study/NCT03855332; Unique identifier: NCT03855332.

The effect of cilostazol on late outcomes after endovascular treatment for occlusive femoropopliteal disease.

OBJECTIVE: Restenosis and late occlusion remain a significant problem for endovascular treatment of peripheral artery disease. This meta-analysis aims to evaluate the effect of cilostazol on late outcomes after endovascular repair of occlusive femoropopliteal disease. METHODS: A systematic literature review was conducted conforming to established criteria to identify articles published up to September 2023 evaluating late outcomes after endovascular treatment for atherosclerotic femoropopliteal disease. Eligible studies should compare outcomes between patients treated with cilostazol and patients not treated with cilostazol. Both prospective and retrospective studies were eligible. Late outcomes included primary patency (PP), restenosis, target lesion revascularization (TLR), and major amputation during follow-up. RESULTS: Overall, 10 clinical studies were identified for analysis including 4721 patients (1831 with cilostazol vs 2890 without cilostazol) that were treated for 5703 lesions (2235 with cilostazol vs 3468 without cilostazol). All studies were performed in Japan. Mean follow-up was 24.1 ± 12.5 months. Cilostazol was associated with a lower risk for restenosis (pooled odds ratio [OR], 0.503; 95% confidence interval [CI], 0.383-0.660; P < .0001). However, no association was found between cilostazol and TLR (pooled OR, 0.918; 95% CI, 0.300-2.812; P = .881) as well as major amputation (pooled OR, 1.512; 95% CI, 0.734-3.116; P = .263). Regarding primary patency, cilostazol was associated with a higher 12-month PP (OR, 3.047; 95% CI, 1.168-7.946; P = .023), and a higher 36-month PP (OR, 1.616; 95% CI, 1.412-1.850; P < .0001). No association was found between cilostazol and mortality during follow-up (pooled OR, .755; 95% CI, 0.293-1.946; P = .561). CONCLUSIONS: Cilostazol seems to have a positive effect on 1- to 3-year PP and restenosis rates among patients treated endovascularly for atherosclerotic femoropopliteal disease. A positive effect on TLR and amputation risk was not verified in this review.

Second messenger signalling bypasses CGRP receptor blockade to provoke migraine attacks in humans.

There are several endogenous molecules that can trigger migraine attacks when administered to humans. Notably, calcitonin gene-related peptide (CGRP) has been identified as a key player in a signalling cascade involved in migraine attacks, acting through the second messenger cyclic adenosine monophosphate (cAMP) in various cells, including intracranial vascular smooth muscle cells. However, it remains unclear whether intracellular cAMP signalling requires CGRP receptor activation during a migraine attack in humans. To address this question, we conducted a randomized, double-blind, placebo-controlled, parallel trial using a human provocation model involving the administration of CGRP and cilostazol in individuals with migraine pretreated with erenumab or placebo. Our study revealed that migraine attacks can be provoked in patients by cAMP-mediated mechanisms using cilostazol, even when the CGRP receptor is blocked by erenumab. Furthermore, the dilation of cranial arteries induced by cilostazol was not influenced by the CGRP receptor blockade. These findings provide clinical evidence that cAMP-evoked migraine attacks do not require CGRP receptor activation. This discovery opens up new possibilities for the development of mechanism-based drugs for the treatment of migraine.

The Use and Impact of Cilostazol on Patients Undergoing Endovascular Peripheral Interventions.

BACKGROUND: Cilostazol is used for the treatment of intermittent claudication. The impact of cilostazol on the outcomes of peripheral vascular interventions (PVIs) remains controversial. This study assesses the use and impact of cilostazol on patients undergoing PVI for peripheral arterial disease (PAD). METHODS: The Vascular Quality Initiative (VQI) database files for PVI were reviewed. Patients with PAD who underwent PVI for chronic limb threatening-ischemia or claudication were included and divided based on the use of cilostazol preoperatively. After propensity matching for patient demographics and comorbidities, the short-term and long-term outcomes of the 2 groups (preoperative cilostazol use versus no preoperative cilostazol use) were compared. The Kaplan-Meier method was used to determine outcomes. RESULTS: A total of 245,309 patients underwent PVI procedures and 6.6% (N = 16,366) were on cilostazol prior to intervention. Patients that received cilostazol were more likely to be male (62% vs 60%; P < 0.001), White (77% vs. 75%; P < 0.001), and smokers (83% vs. 77%; P < 0.001). They were less likely to have diabetes mellitus (50% vs. 56%; P < 0.001) and congestive heart failure (14% vs. 23%; P < 0.001). Patient on cilostazol were more likely to be treated for claudication (63% vs. 40%, P < 0.001), undergo prior lower extremity revascularization (55% vs. 51%, P < 0.001) and less likely to have undergone prior minor and major amputation (10% vs. 19%; P < 0.001) compared with patients who did not receive cilostazol. After 3:1 propensity matching, there were 50,265 patients included in the analysis with no differences in baseline characteristics. Patients on cilostazol were less likely to develop renal complications and more likely to be discharged home. Patients on cilostazol had significantly lower rates of long-term mortality (11.5% vs. 13.4%, P < 0.001 and major amputation (4.0% vs. 4.7%, P = 0.022). However, there were no significant differences in rates of reintervention, major adverse limb events, or patency after PVI. Amputation-free survival rates were significantly higher for patients on cilostazol, after 4 years of follow up (89% vs. 87%, P = 0.03). CONCLUSIONS: Cilostazol is underutilized in the VQI database and seems to be associated with improved amputation-free survival. Cilostazol therapy should be considered in all patients with PAD who can tolerate it prior to PVI.

Cilostazol for peripheral arterial disease - a position paper from the Italian Society for Angiology and Vascular Medicine.

Cilostazol is a quinolinone-derivative selective phosphodiesterase inhibitor and is a platelet-aggregation inhibitor and arterial vasodilator for the symptomatic treatment of intermittent claudication (IC). Cilostazol has been shown to improve walking distance for patients with moderate to severe disabling intermittent claudication who do not respond to exercise therapy and who are not candidates for vascular surgical or endovascular procedures. Several studies evaluated the pharmacological effects of cilostazol for restenosis prevention and indicated a possible effect on re-endothelialization mediated by hepatocyte growth factor and endothelial precursor cells, as well as inhibiting smooth muscle cell proliferation and leukocyte adhesion to endothelium, thereby exerting an anti-inflammatory effect. These effects may suggest a potential effectiveness of cilostazol in preventing restenosis and promoting the long-term outcome of revascularization interventions. This review aimed to point out the role of cilostazol in treating patients with peripheral arterial disease, particularly with IC, and to explore its possible role in restenosis after lower limb revascularization.

Long-term effectiveness and safety of cilostazol versus clopidogrel in secondary prevention of noncardioembolic ischemic stroke.

PURPOSE: Cilostazol is a widely used antiplatelet drug for secondary stroke prevention in Asia, but its comparison with clopidogrel is not well understood. This study aims to investigate the effectiveness and safety of cilostazol compared to clopidogrel for the secondary prevention of noncardioembolic ischemic stroke. METHODS: This retrospective comparative effectiveness research analyzed 1:1 propensity scorematched data from insured individuals between 2012 and 2019, using administrative claims data in Health Insurance Review and Assessment in Korea. Patients with diagnosis codes for ischemic stroke without cardiac disease were included and divided into two groups, those receiving cilostazol and those receiving clopidogrel. The primary outcome was a recurrent ischemic stroke. Secondary outcomes included all-cause death, myocardial infarction, hemorrhagic stroke, and a composite of these outcomes. The safety outcome was major gastrointestinal bleeding. RESULTS: The study analyzed 4,754 patients in the propensity scorematched population and found no statistically significant difference in recurrent ischemic stroke (cilostazol group vs clopidogrel group, 2.7% vs 3.2%; 95% CI, 0.62-1.21), the composite outcome of recurrent ischemic stroke, all-cause death, myocardial infarction, and hemorrhagic stroke (5.1% vs 5.5%; 0.75-1.22), and major gastrointestinal bleeding (1.3% vs 1.5%; 0.57-1.47) between patients receiving cilostazol and those receiving clopidogrel. In subgroup analysis, cilostazol was associated with a lower incidence of recurrent ischemic stroke compared to clopidogrel in hypertensive patients (2.5% vs 3.9%; interaction P = 0.041). CONCLUSIONS: This real-world study suggests that cilostazol is effective and safe for noncardioembolic ischemic stroke and may be associated with better effectiveness in hypertensive patients compared to clopidogrel.

Cilostazol Versus Aspirin on White Matter Changes in Cerebral Small Vessel Disease: A Randomized Controlled Trial.

BACKGROUND AND PURPOSE: Cerebral small vessel disease is characterized by progressive cerebral white matter changes (WMCs). This study aimed to compare the effects of cilostazol and aspirin on changes in WMC volume in patients with cerebral small vessel disease. METHODS: In a multicenter, double-blind, randomized controlled trial, participants with moderate or severe WMCs and at least one lacunar infarction detected on brain magnetic resonance imaging were randomly assigned to the cilostazol and aspirin groups in a 1:1 ratio. Cilostazol slow release (200 mg) or aspirin (100 mg) capsules were administered once daily for 2 years. The primary outcome was the change in WMC volume on magnetic resonance images from baseline to 2 years. Secondary imaging outcomes include changes in the number of lacunes or cerebral microbleeds, fractional anisotropy, and mean diffusivity on diffusion tensor images, and brain atrophy. Secondary clinical outcomes include all ischemic strokes, all ischemic vascular events, and changes in cognition, motor function, mood, urinary symptoms, and disability. RESULTS: Between July 2013 and August 2016, 256 participants were randomly assigned to the cilostazol (n=127) and aspirin (n=129) groups. Over 2 years, the percentage of WMC volume to total WM volume and the percentage of WMC volume to intracranial volume increased in both groups, but neither analysis showed significant differences between the groups. The peak height of the mean diffusivity histogram in normal-appearing WMs was significantly reduced in the aspirin group compared with the cilostazol group. Cilostazol significantly reduced the risk of ischemic vascular event compared with aspirin (0.5 versus 4.5 cases per 100 person-years; hazard ratio, 0.11 [95% CI, 0.02-0.89]). CONCLUSIONS: There was no significant difference between the effects of cilostazol and aspirin on WMC progression in patients with cerebral small vessel disease. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01932203.

Cilostazol for Aneurysmal Subarachnoid Hemorrhage: An Updated Systematic Review and Meta-Analysis.

BACKGROUND AND PURPOSE: Delayed cerebral ischemia is a major cause of morbidity and mortality in patients with aneurysmal subarachnoid hemorrhage (aSAH). Cilostazol, a selective inhibitor of phosphodiesterase 3, was reported to reduce cerebral vasospasm and improve outcomes. We aimed to conduct an updated systematic review and meta-analysis of the efficacy and safety of cilostazol in aSAH. METHODS: We systematically searched PubMed, Embase, MEDLINE, and the Cochrane Library for articles published in English with the latest publishing time in August 2020. Articles reporting favorable outcome as the primary outcome and reporting severe angiographic vasospasm (aVS), symptomatic vasospasm (sVS), new cerebral infarction, or mortality as the secondary outcome were included in this review. Furthermore, we examined whether clinical outcomes were associated with the dosage of cilostazol (300 mg/day vs. 100-200 mg/day). RESULTS: Data from 405 patients in 4 randomized controlled trials (RCTs) and 461 patients in 4 observational studies (OSs) were included. In RCT studies, cilostazol was associated with significant favorable outcomes at discharge or 1 month (risk ratio [RR] 1.41, 95% confidence interval [CI] 1.01-1.97, p = 0.04) or 3 or 6 months (RR 1.16, 95% CI 1.05-1.28, p = 0.002). However, in OSs, no significant difference was indicated in favorable outcomes at discharge or 1 month (RR 1.22, 95% CI 0.94-1.60, p = 0.14) nor 3 or 6 months (RR 1.29, 95% CI 0.92-1.81, p = 0.14). The analyses found that cilostazol significantly reduced the incidences of severe aVS (RCT: RR 0.64, 95% CI 0.41-1.01, p = 0.05; OS: RR 0.61, 95% CI 0.43-0.88, p = 0.007), sVS (RCT: RR 0.46, 95% CI 0.31-0.70, p = 0.0002; OS: RR 0.38, 95% CI 0.21-0.68, p = 0.001), and new cerebral infarction (RCT: RR 0.40, 95% CI 0.24-0.67, p = 0.0005; OS: RR 0.38, 95% CI 0.23-0.64, p = 0.0002). However, no significant difference in mortality (RCT: RR 0.86, 95% CI 0.23-3.21, p = 0.82; OS: RR 0.16, 95% CI 0.02-1.24, p = 0.08) was found. In 3 OSs which reported different doses of cilostazol (300 mg/day vs. 100-200 mg/day) for aSAH, the 300-mg/day cilostazol groups showed decreased delayed cerebral infarction (RR 0.27, 95% CI 0.09-0.81, p = 0.02) but no significant difference in shunt-dependent hydrocephalus (RR 0.92, 95% CI 0.33-2.60, p = 0.88) or functional outcomes (RR 1.14, 95% CI 0.74-1.75, p = 0.56) compared with the 100-200 mg/day cilostazol groups. CONCLUSIONS: The meta-analyses suggest the credible efficacy and safety of cilostazol in treating aSAH. Furthermore, 300-mg/day cilostazol treatment appeared to be more effective than 100-200 mg/day treatment.

Efficacy and Safety of Cilostazol for Atherosclerosis: A Meta-analysis of Randomized Controlled Trials.

ABSTRACT: To investigate the efficacy and safety of cilostazol for atherosclerosis. PubMed, Embase, and the Cochrane Central Register of Controlled Trials from inception to May 29, 2021, were searched for randomized clinical trials (RCTs). Ten trials with 1577 patients were included. Treatment with cilostazol significantly reduced carotid intima-media thickness [mean difference (MD), -0.12 mm; 95% confidence interval (CI), -0.17 to -0.06]. According to the difference in intervening measures, the cilostazol group was superior to the control group in inhibiting the progression of carotid intima-media thickness: cilostazol versus placebo (MD, -0.04 mm; 95% CI, -0.06 to -0.02; P < 0.00001), cilostazol versus no antiplatelet drug (MD, -0.14 mm; 95% CI, -0.26 to -0.03; P = 0.02), cilostazol versus aspirin (MD, -0.17 mm; 95% CI, -0.32 to -0.02; P = 0.02), cilostazol + aspirin versus aspirin (MD, -0.08 mm; 95% CI, -0.14 to -0.02; P = 0.007), cilostazol + aspirin versus clopidogrel + aspirin (MD, -0.07 mm; 95% CI, -0.14 to -0.00; P = 0.04), and cilostazol + clopidogrel + aspirin versus clopidogrel + aspirin (MD, -0.16 mm; 95% CI, -0.30 to -0.02; P = 0.03). Cilostazol treatment considerably decreased triglyceride (MD, -20.18 mg/dL; 95% CI, -39.03 to -1.34) and improved high-density lipoprotein cholesterol (MD, 4.35 mg/dL; 95% CI, 2.61-6.10). Cilostazol therapy significantly increased the risk of adverse events of headache (odds ratio, 12.91; 95% CI 5.33-31.29). Our research has revealed that cilostazol has potent antiatherosclerotic effects and can reverse atherosclerosis progress even in high-risk patients, such as those with type 2 diabetes mellitus, and does not increase the risk of bleeding.

Dual Antiplatelet Therapy Using Cilostazol With Aspirin or Clopidogrel: Subanalysis of the CSPS.com Trial.

Background and Purpose: Although dual antiplatelet therapy (DAPT) with aspirin and clopidogrel reduces the recurrence of ischemic stroke while significantly increasing the bleeding events compared with monotherapy, the CSPS.com trial (Cilostazol Stroke Prevention Study combination) showed that DAPT using cilostazol was more effective without the bleeding risk. In the CSPS.com trial, aspirin or clopidogrel was used as the underlying antiplatelet drug. The effectiveness and safety of each combination were examined and clarified. Methods: In the CSPS.com trial, a multicenter, open-label, randomized controlled study, patients with high-risk, noncardioembolic ischemic stroke 8 to 180 days after onset treated with aspirin or clopidogrel alone at the discretion of the physician in charge were recruited. Patients were randomly assigned to receive either monotherapy or DAPT using cilostazol and followed for 0.5 to 3.5 years. The primary efficacy outcome was first recurrence of ischemic stroke. The safety outcome was severe or life-threatening bleeding. The analysis was based on the underlying antiplatelet agents. Results: A total of 763 patients taking aspirin and 1116 taking clopidogrel were included in the intention-to-treat analysis. Although the clopidogrel group had more risk factors than the aspirin group, the primary efficacy outcome and safety outcome did not differ significantly between the 2 groups. In the aspirin group, the primary efficacy outcome and safety outcome did not differ significantly between the DAPT group and the aspirin-monotherapy group. In the clopidogrel group, the primary end point occurred at a rate of 2.31 per 100 patient-years in the DAPT group and 5.19 per 100 patient-years in the clopidogrel-monotherapy group (hazard ratio, 0.447 [95% CI, 0.258­0.774]). Safety outcome did not differ significantly between groups (0.51 per 100 patient-years versus 0.71 per 100 patient-years, respectively; hazard ratio, 0.730 [95% CI, 0.206­2.588]). Conclusions: The combination of cilostazol and clopidogrel significantly reduced the recurrence of ischemic stroke without increasing the bleeding risk in noncardioembolic, high-risk patients. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01995370. URL: https://www.umin.ac.jp/ctr/; Unique identifier: UMIN000012180.

Identification and functional study of genetic polymorphisms in cyclic nucleotide phosphodiesterase 3A (PDE3A).

Phosphodiesterase 3A (PDE3A) is an enzyme that plays an important role in the regulation of cyclic adenosine monophosphate (cAMP)-mediated intracellular signaling in cardiac myocytes and platelets. PDE3A hydrolyzes cAMP, which results in a decrease in intracellular cAMP levels and leads to platelet activation. Whole-exome sequencing of 50 DNA samples from a healthy Korean population revealed a total of 13 single nucleotide polymorphisms including five missense variants, D12N, Y497C, H504Q, C707R, and A980V. Recombinant proteins for the five variants of PDE3A (and wild-type protein) were expressed in a FreeStyle 293 expression system with site-directed mutagenesis. The expression of the recombinant PDE3A proteins was confirmed with Western blotting. Catalytic activity of the PDE3A missense variants and wild-type enzyme was measured with a PDE-based assay. Effects of the missense variants on the inhibition of PDE3A activity by cilostazol were also investigated. All variant proteins showed reduced activity (33-53%; p < .0001) compared to the wild-type protein. In addition, PDE3A activity was inhibited by cilostazol in a dose-dependent manner and was further suppressed in the missense variants. Specifically, the PDE3A Y497C showed significantly reduced activity, consistent with the predictions of in silico analyses. The present study provides evidence that individuals carrying the PDE3A Y497C variant may have lower enzyme activity for cAMP hydrolysis, which could cause interindividual variation in cAMP-mediated physiological functions.

Literature review and meta-analysis of the efficacy of cilostazol on limb salvage rates after infrainguinal endovascular and open revascularization.

BACKGROUND: Current clinical guidelines recommend the use of cilostazol in the treatment of patients with infrainguinal peripheral artery disease (PAD) who experience intermittent claudication. However, the role of cilostazol therapy in patients with advanced PAD and critical limb ischemia (CLI) remains unclear. To conduct a meta-analysis of randomized controlled trials and cohort studies that evaluated the effect of cilostazol vs standard antiplatelet therapy on limb-related and arterial patency-related outcomes. We also reviewed literature pertinent to the effect of cilostazol on wound healing in patients with advanced PAD. METHODS: We performed a MEDLINE, EMBASE, COCHRANE (CENTRAL), SCOPUS, and US Clinical Trials database search for all trials and studies since 1999 that compared cilostazol with standard antiplatelet therapy in the setting of infrainguinal PAD revascularization procedures (endovascular or open). Aggregate data was collected from four randomized control trials and six retrospective cohort studies. The end point incidence ratios and treatment effects were generated from each study and reported as hazard ratios (HR) using a random-effect model. We also reviewed 10 studies that evaluated the effect of cilostazol on wound healing in patients with advanced PAD. RESULTS: From more than 25,000 total patients, 3136 patients met our inclusion criteria. All patients had at least lifestyle-impacting intermittent claudication, and more than 50% met the definition of CLI (Rutherford class ≥4). Patient age range was 53 to 83 years, and the majority were male (66%). The mean follow-up time averaged 2 years across all studies. Meta-analysis revealed that cilostazol treatment favored amputation-free survival (hazard ratio [HR], 0.79; 95% confidence interval [CI], 0.69-0.91), limb salvage rate (HR, 0.42; 95% CI, 0.27-0.66), decreased repeat revascularization (risk ratio [RR], 0.44; 95% CI, 0.37-0.52), and decreased restenosis (RR, 0.68; 95% CI, 0.61-0.76). Cilostazol treatment also increased freedom from target lesion revascularization (RR, 1.35; 95% CI, 1.21-1.53) with no difference in all-cause mortality. Effective wound healing was found to be an inconsistent outcome measure in patients receiving cilostazol therapy. CONCLUSIONS: We observed that cilostazol therapy has a beneficial impact on all limb-related and arterial patency-related outcomes, but no effect on all-cause mortality in patients with advanced PAD and CLI undergoing revascularization procedures. Additional studies are needed to evaluate the effect of cilostazol therapy on wound healing in patients with advanced PAD.

Impact of Cilostazol Pharmacokinetics on the Development of Cardiovascular Side Effects in Patients with Cerebral Infarction.

This study investigated the impact of polymorphisms of metabolic enzymes on plasma concentrations of cilostazol and its metabolites, and the influence of the plasma concentrations and polymorphisms on the cardiovascular side effects in 30 patients with cerebral infarction. Plasma concentrations of cilostazol and its active metabolites, and CYP3A5*3 and CYP2C19*2 and *3 genotypes were determined. The median plasma concentration/dose ratio of OPC-13213, an active metabolite by CYP3A5 and CYP2C19, was slightly higher and the median plasma concentration rate of cilostazol to OPC-13015, another active metabolite by CYP3A4, was significantly lower in CYP3A5*1 carriers than in *1 non-carriers (p = 0.082 and p = 0.002, respectively). The CYP2C19 genotype did not affect the pharmacokinetics of cilostazol. A correlation was observed between changes in pulse rate from the baseline and plasma concentrations of cilostazol (R = 0.539, p = 0.002), OPC-13015 (R = 0.396, p = 0.030) and OPC-13213 (R = 0.383, p = 0.037). A multiple regression model, consisting of factors of the plasma concentration of OPC-13015, levels of blood urea nitrogen, and pulse rate at the start of the therapy explained 55.5% of the interindividual variability of the changes in pulse rate. These results suggest that plasma concentrations of cilostazol and its metabolites are affected by CYP3A5 genotypes, and plasma concentration of OPC-13015, blood urea nitrogen, and pulse rate at the start of therapy may be predictive markers of cardiovascular side effects of cilostazol in patients with cerebral infarction.

Cilostazol Versus Aspirin for Secondary Stroke Prevention: Systematic Review and Meta-Analysis.

OBJECTIVES: Cilostazol has promise as an alternative to aspirin for secondary stroke prevention given its vasodilatory and anti-inflammatory properties in addition to platelet aggregation inhibition. We aimed to conduct a systematic review and meta-analysis to estimate the efficacy and safety of cilostazol compared to aspirin for stroke prevention in patients with previous stroke or transient ischemic attack (TIA). MATERIALS AND METHODS: We searched PubMed and the Cochrane Central Register of Controlled Trials from 1996 to 2019. Randomized clinical trials that compared cilostazol to aspirin and reported the endpoints of ischemic stroke, intracranial hemorrhage and any bleeding were included. A random-effects estimate was computed based on the Mantel-Haenszel method. The pooled risk estimates with 95% confidence intervals were compared between cilostazol and aspirin. RESULTS: The search identified 5 randomized clinical trials comparing cilostazol vs. aspirin for secondary stroke prevention that collectively enrolled 7240 patients, all from Asian countries (3615 received cilostazol and 3625 received aspirin). Pooled results from the random-effects model showed that cilostazol was associated with significantly lower risk of recurrent ischemic stroke (RR 0.68; 95% CI, 0.54 to 0.87), intracranial hemorrhage (RR 0.42; 95% CI, 0.27 to 0.65) and any bleeding (RR 0.71; 95% CI, 0.55 to 0.91). CONCLUSIONS: This meta-analysis suggests that cilostazol is more effective than aspirin in preventing recurrent ischemic stroke with lower risk of intracranial hemorrhage and other bleeding. Since all trials to date are from Asian countries, confirmatory trials of cilostazol for secondary stroke prevention in other populations are needed.

Cilostazol Addition to Aspirin could not Reduce the Neurological Deterioration in TOAST Subtypes: ADS Post-Hoc Analysis.

BACKGROUND: Our previous trial acute dual study (ADS) reported that dual antiplatelet therapy (DAPT) using cilostazol and aspirin did not reduce the rate of short-term neurological worsening in non-cardioembolic stroke patients. Present post-hoc analysis investigated whether the impact of combined cilostazol and aspirin differed among stroke subtypes and factors associated with neurological deterioration and/or stroke recurrence. METHODS: Using the ADS registry, the rate of neurological deterioration, defined as clinical worsening and/or recurrent stroke, including transient ischemic attack was calculated. Stroke subtypes included large-artery atherosclerosis (LAA), small vessel occlusion (SVO), other determined etiology (Others), and undetermined etiology of stroke (Undetermined). RESULTS: Data of 1022 patients were analyzed. Deterioration was seen in 104 (10%) patients, and the rates were not markedly different between patients treated with DAPT vs. aspirin in any stroke subtypes: LAA, 19% vs. 11%, (p=0.192); SVO, 10% vs. 10% (p=1.000); Others, 6% vs. 6% (p=1.000); Undetermined, 11% vs. 8% (p=0.590). Diabetes mellitus was the independent factor associated with deterioration (odds ratio 4.360, 95% confidence interval 1.139-16.691, p=0.032) in the LAA group. Age (1.030 [1.004-1.057], p=0.026), systolic blood pressure (1.012 [1.003-1.022], p=0.010), and infarct size (2.550 [1.488-4.371], p=0.001) were associated with deterioration in SVO group, and intracranial stenosis/occlusion was associated with it in the Undetermined group (3.744 [1.138-12.318], p=0.030). CONCLUSIONS: Combined cilostazol and aspirin did not reduce the rate of short-term neurological deterioration in any clinical stroke subtype. The characteristics of patients whose condition deteriorates in the acute period may differ based on the stroke subtypes.

Positive chronotropic effects of theophylline and cilostazol in patients with symptomatic sick sinus syndrome who have declined permanent pacing.

Pacemakers are more commonly recommended than theophylline for sick sinus syndrome (SSS) treatment. The positive effects of cilostazol on bradyarrhythmias also have been reported. However, no comparison of cilostazol and theophylline has been previously reported found. We retrospectively enrolled SSS patients, who refused a pacemaker implantation. Theophylline or cilostazol was administered, and the heart rate (HR) was evaluated in 4-8 weeks using a digital sphygmomanometer and the electrocardiogram (ECG). A 200-400 mg of theophylline or 100-200 mg of cilostazol were administered per day in 50 and 30 patients, respectively. The baseline HR was 54.8 ± 13.5 beats per minute (bpm) on using sphygmomanometry and 51.9 ± 11.8 bpm using the ECG. In the theophylline group, the HR increased by 12.0 ± 16.3 bpm by sphygmomanometry (P < 0.001) and 8.4 ± 12.0 bpm by the ECG (P < 0.001). In the cilostazol group, the HR increased by 16.8 ± 13.9 bpm by sphygmomanometry (P < 0.001) and 12.4 ± 13.4 bpm using the ECG (P < 0.001). In 15 of the 50 theophylline patients, the medication was switched to cilostazol. The HR increased from 61.4 ± 13.8 bpm to 64.0 ± 12.6 bpm (P = 0.338). Symptoms such as dyspnea, chest discomfort, dizziness, and syncope significantly improved after the administration of the medications. There were no significant differences in the improvement in the symptoms except for dizziness between the two agents. Cilostazol was as effective as theophylline for increasing the HR in SSS patients.

Subcutaneous sumatriptan reduces cilostazol induced headache in migraine patients.

OBJECTIVES: The authors have previously tried to develop a model for the testing of novel drug candidates for migraine, using the headache and migraine provoking agent cilostazol. Previous studies have used sumatriptan tablets as the validating drug, but they were not sufficiently effective. In this study we test the effect of subcutaneous sumatriptan on cilostazol induced headache in patients with migraine without aura. METHOD: Thirty patients with migraine without aura received 200 mg cilostazol on two different study days. The induced headache was treated with subcutaneous sumatriptan in a randomized, double-blind cross-over design. The patients filled out a self-reported headache questionnaire until 12 h after cilostazol. RESULTS: All 30 patients experienced headache (range 3-10) on both study days and the headache fulfilled the criteria for a migraine-like attack in 73% on the sumatriptan day and in 77% on the placebo day. Sumatriptan injection reduced the headache score 2 h after treatment (p = 0.003). The difference between headache intensity on the sumatriptan day and the placebo day was significant at both 2 h (p = 0.01) and 4 h (p = 0.0007) after treatment. CONCLUSION: Subcutaneous sumatriptan reduces cilostazol induced headache in migraine patients. The cilostazol model may be useful as a tool to test the potential of new anti-migraine drugs.Trial registration: The study is registered on clinicaltrials.gov (NCT03422796).

Cilostazol-based triple versus potent P2Y12 inhibitor-based dual antiplatelet therapy in patients with acute myocardial infarction undergoing percutaneous coronary intervention.

Although potent P2Y12 inhibitor-based dual antiplatelet therapy (DAPT) has replaced clopidogrel-based therapy as the standard treatment in patients with acute myocardial infarction (AMI), there is a concern about the risk of bleeding in East Asian patients. We compared the efficacy and safety of cilostazol-based triple antiplatelet therapy (TAT) with potent P2Y12 inhibitor-based DAPT in Korean patients. A total of 4152 AMI patients who underwent percutaneous coronary intervention (PCI) in the Korea Acute Myocardial Infarction Registry were analyzed retrospectively. Patients were divided into two groups: the TAT group (aspirin + clopidogrel + cilostazol, n = 3161) and the potent DAPT group (aspirin + potent P2Y12 inhibitors [ticagrelor or prasugrel], n = 991). Major clinical outcomes at 30 days and 2 years were compared between the two groups using propensity score matching (PSM) analysis. After PSM (869 pairs), there were no significant differences between the two groups in the incidence of total death, cardiac death, myocardial infarction (MI), target vessel revascularization, stent thrombosis, and stroke at 30 days and 2 years. However, the Thrombolysis in Myocardial Infarction (TIMI) major or minor bleeding rates were significantly lower in the TAT group compared with the potent DAPT group at 2 years (6.4% vs. 3.6%, p = 0.006). In Korean AMI patients undergoing PCI, TAT with cilostazol was associated with lower bleeding than the potent P2Y12 inhibitor-based DAPT without increased ischemic risk. These results could provide a rationale for the use of TAT in East Asian AMI patients.

Randomized Comparisons of Double-Dose Clopidogrel or Adjunctive Cilostazol Versus Standard Dual Antiplatelet in Patients With High Posttreatment Platelet Reactivity: Results of the CREATIVE Trial.

BACKGROUND: Patients undergoing percutaneous coronary intervention react differently to antiplatelet drugs. Those with low responsiveness to clopidogrel have a higher risk of cardiac ischemic events. The goal of this study is to conduct a head-to-head comparison of the safety and effectiveness of intensified antiplatelet therapies (either double-dose clopidogrel [DOUBLE] or adjunctive cilostazol [TRIPLE]) and conventional strategy (STANDARD) in patients after percutaneous coronary intervention. METHODS: In this single-center, randomized, controlled trial, we used thromboelastography, a platelet function test, to select 1078 patients undergoing percutaneous coronary intervention at high thrombotic risk and compared the intensified antiplatelet therapies with standard antiplatelet therapy. The primary outcome was the incidence of major adverse cardiac and cerebrovascular events at 18 months after percutaneous coronary intervention, defined as a composite of all-cause death, myocardial infarction, target vessel revascularization, or stroke. Bleeding Academic Research Consortium defined bleeding complications (types 1, 2, 3, or 5) were the safety end points. RESULTS: The primary end point occurred in 52 patients (14.4%) in the STANDARD group, 38 patients (10.6%) in the DOUBLE group, and 30 patients (8.5%) in the TRIPLE group (hazard ratio, 0.720; 95% confidence interval, 0.474-1.094, DOUBLE versus STANDARD; hazard ratio, 0.550; 95% confidence interval, 0.349-0.866, TRIPLE versus STANDARD). No significant difference in the rates of major bleeding (Bleeding Academic Research Consortium grade≥3) was found in the DOUBLE group (3.34% versus 1.93% in STANDARD, P=0.133) and the TRIPLE group (2.53% versus 1.93% in STANDARD, P=0.240). The rate of Bleeding Academic Research Consortium-defined minor bleeding increased in the DOUBLE group (27.4% versus 20.3% in STANDARD, P=0.031), but not in the TRIPLE group (23.6% versus 20.3% in STANDARD, P=0.146). CONCLUSIONS: In patients with low responsiveness to clopidogrel, as measured by thromboelastography, the intensified antiplatelet strategies with adjunctive use of cilostazol significantly improved the clinical outcomes without increasing the risk of major bleeding. Decreased trend of negative outcomes could be observed in patients with double dosage of clopidogrel, but the difference was not significant. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: NCT01779401.