Plasma Concentration Of Cilostazol Research Articles

Pharmacokinetic Drug-Drug Interaction between Cilostazol and Rosuvastatin in Healthy Participants.

Cilostazol improves ischemic symptoms and prevents recurrence following cerebral infarction, and rosuvastatin reduces cholesterol levels. However, no reports exist on the pharmacokinetic interactions between these two drugs in healthy adults. This study evaluated the pharmacokinetic (PK) interactions and safety of cilostazol and rosuvastatin when co-administered to healthy male participants. A randomized, open-label, multiple-dosing, two-arm, two-period study was conducted. Arm A had 30 participants receiving 200 mg cilostazol daily and arm B had 27 participants receiving 20 mg rosuvastatin daily for 7 days. In period 2, both arms received a combination of 200 mg cilostazol and 20 mg rosuvastatin daily for 7 days following a 7-day washout period. Plasma concentrations of cilostazol, its metabolites, and rosuvastatin were quantified using liquid chromatography-tandem mass spectrometry. Fifty-seven participants were randomized, and 44 completed the study. The geometric mean ratio (GMR) and 90% confidence intervals (CI) for maximum plasma concentration at steady state (Cmax,ss) and area under the plasma concentration-time curve during the dosing interval at steady state (AUCtau,ss) indicated no significant interaction between cilostazol and rosuvastatin. Safety assessments showed comparable profiles to individual drug administration, with no significant adverse events. The repeated co-administration of cilostazol and rosuvastatin in healthy male participants resulted in minor PK interactions and exhibited a safety and tolerability profile similar to those of the individual drugs. This suggested that the combined regimen is well tolerated and does not necessitate dose adjustments. ClinicalTrials.Gov identifier no. NCT06568133.

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.

Pharmacokinetic study of two extended-release formulations of cilostazol in healthy Korean subjects: A randomized, open-label, multiple-dose, two-period crossover study .

The aim of this study was to compare the pharmacokinetic characteristics and safety of two extended-release formulations of cilostazol after multiple oral doses in healthy Korean subjects. A randomized, open-label, multiple-dose, two-period, crossover study was conducted in 30 healthy male subjects. In each treatment period, subjects received oral doses of 200 mg cilostazol SR (Pletaal SR Cap.) or cilostazol CR (Cilostan CR Tab.) once daily for 5 consecutive days, with a washout period of 9 days. Plasma concentrations of cilostazol and its metabolites were determined using a validated liquid chromatography-tandem mass spectrometry method. 24 subjects completed the study. The maximum plasma concentrations (Cmax,ss, geometric mean (geometric coefficient of variation, CV%)) of cilostazol after cilostazol SR and cilostazol CR regimens were 1,532.7 (43.2%) ng/mL and 548.3 (58.9%) ng/mL, respectively, and the areas under the plasma concentration-time curves within dosing intervals (AUCτ, geometric mean (CV%)) were 17,060.7 (39.2%) h×ng/mL and 7,485.7 (55.0%) h×ng/mL, respectively. The geometric mean ratios (cilostazol SR/cilostazol CR) of the Cmax,ss and AUCτ values were 2.7954 (90% confidence interval: 2.3561 - 3.3166) and 2.2791 (90% confidence interval: 1.9770-2.6273), respectively. Both cilostazol SR and cilostazol CR were well tolerated in all subjects, and no serious adverse events occurred. The total incidence of headache, which is the most common adverse drug reaction, was significantly higher with cilostazol SR (63.0%) than cilostazol CR (25.9%). Cilostazol SR showed significantly higher Cmax and AUCτ of cilostazol than cilostazol CR after 5 days of multiple dosing of extended-release formulations of cilostazol.

Pharmacokinetic modeling analysis of cilostazol and its active metabolites (OPC-13015 and OPC-13213) after multiple oral doses of cilostazol in healthy Korean volunteers

Cilostazol is a selective inhibitor of phosphodiesterase III (PDE III), which is prescribed for patients with peripheral arterial disease, especially intermittent claudication. The purpose of the study was to investigate the pharmacokinetic (PK) of cilostazol and its metabolites on the immediate (IR) formulation of cilostazol in healthy Korean male volunteers by population PK modeling analysis implemented using NONMEM software.A 2 × 2 crossover study comparing multiple oral doses of IR and SR formulations of cilostazol were conducted. Serial plasma concentrations of cilostazol and its active metabolites were used in this analysis.The PK was best depicted by one-compartment model, with absorption kinetics of cilostazol having mixed first- and zero-order kinetics with a time delay at the beginning of absorption. The introduction of interoccasion variabilities into zero-order (D1), first-order (Ka), and relative bioavailability (F1) significantly improved the model fit, and total body water (TBW) was identified as a significant covariate positively affecting the clearance of cilostazol. The model validation suggested that the model constructed in this study predicted the plasma concentration of cilostazol and its two active metabolites reasonably well.The PK model we developed explored the PK characteristics of cilostazol in Korean male subjects, and may be useful for identifying optimal individual dosing regimens of cilostazol.

Double controlled release of highly insoluble cilostazol using surfactant-driven pH dependent and pH-independent polymeric blends and in vivo bioavailability in beagle dogs

Commercially available cilostazol (CIL) tablet releases drug immediately and is given twice a day as an antiplatelet and vasodilatory agent. However, clinical usefulness of immediate release (IR) preparation is limited due to its extremely poor water solubility and the difficulty in sustaining the blood concentration, resulting in unwanted side effects such as headaches, pyknocardia and heavy-headed symptoms. To achieve once a day dosage form with enhanced solubility and controlled release, double controlled release CIL matrix tablets (DCRT) were designed by modulating a sol–gel process of binary polymeric blends of a pH-independent hydroxylpropylmethylcellulose (HPMC) and a pH-dependent polymer (carbomer) assisted with anionic surfactant (sodium lauryl sulfate, SLS). The release profiles of the DCRT were varied according to the ratio of the two polymers. This DCRT enhanced dissolution rate of CIL in a controlled manner due to the sol–gel and erosion process of HPMC, and SLS-driven modulation of charged carbomer via neutralization and micellar interaction. The near-infrared (NIR) chemical imaging and gravimetric behaviors of DCRT clearly showed dynamic modulation of CIL during the swelling and hydration process. Furthermore, the plasma concentration of CIL in DCRT was highly improved and sustained in beagle dogs in a controlled manner.

Population Pharmacokinetic Analysis of Diurnal and Seasonal Variations of Plasma Concentrations of Cilostazol in Healthy Volunteers

The background of this study was (1) to examine factors influencing cilostazol pharmacokinetics by developing a population model incorporating diurnal variation and other covariate effects and (2) to assess the feasibility of applying the developed model to determine the optimal dosing times. Data obtained from a cilostazol pharmacokinetic study consisting of 2 clinical trials (a single twice-a-day (BID) dosing trial in winter and a multiple BID dosing trial in summer) conducted in healthy Korean subjects were used for model building. A basic model was built, followed by a diurnal variation model, and then a final model was built incorporating covariates, including a seasonal difference. The optimal morning and evening dosing times were determined from simulations. Diurnal variation in cilostazol pharmacokinetics was explained by the morning absorption rate constant being faster than in the evening, yielding values of 0.278 versus 0.234/h in summer, when 24- and 12-hour circadian rhythms were included in the model. The seasonal variation was explained by a 26.9% and a 31.8% decrease in the absorption rate constant and clearance, respectively, in winter compared with summer. Based on twice-a-day (BID) dosing, dosing times of 9 AM and 5 PM in summer and 10 AM and 7 PM in winter were expected to produce the smallest peak-to-peak fluctuations in cilostazol concentration, possibly minimizing unwanted effects of the drug. This study demonstrated the intraday and interseasonal time-varying nature of cilostazol pharmacokinetics using a population modeling approach and developed a strategy for optimizing dosing times. It is suggested that these methods can be similarly applied to analyses and controls of other drugs that exhibit characteristics of time-varying pharmacokinetics.

The effect of Ginkgo biloba extracts on the pharmacokinetics and pharmacodynamics of cilostazol and its active metabolites in healthy Korean subjects

The primary objective of this study was to evaluate the effects of Ginkgo biloba extracts (GBE) on the pharmacokinetics of cilostazol and its metabolites. The secondary objective was to assess the effect of GBE on the pharmacodynamics of cilostazol. A randomized, double-blind, two-way crossover study was conducted with 34 healthy Korean subjects. All subjects were given an oral dose of cilostazol (100 mg) plus GBE (80 mg) or cilostazol (100 mg) plus placebo twice daily for 7 days. Plasma concentrations of cilostazol and its active metabolites (3,4-dehydrocilostazol and 4'-trans-hydroxycilostazol) were measured using liquid chromatography-tandem mass spectroscopy on day 7 for pharmacokinetic assessment. The adenosine diphosphate-induced platelet aggregation and bleeding time were measured at baseline and on day 7 for pharmacodynamic assessment. The geometric mean ratios of area under the concentration-time curve for dosing interval for cilostazol plus GBE vs. cilostazol plus placebo were 0.96 (90% confidence interval, 0.89-1.03; P = 0.20) for cilostazol, 0.96 (90% confidence interval, 0.90-1.02; P = 0.30) for 3,4-dehydrocilostazol and 0.98 (90% confidence interval, 0.93-1.03; P = 0.47) for 4'-trans-hydroxycilostazol. The change of aggregation after administration of cilostazol plus GBE seemed to be 1.31 times higher compared with cilostazol plus placebo, without statistical significance (P = 0.20). There were no significant changes in bleeding times and adverse drug reactions between the treatments. Co-administration of GBE showed no statistically significant effects on the pharmacokinetics of cilostazol in healthy subjects. A large cohort study with long-term follow-up may be needed to evaluate the possible pharmacodynamic interaction between cilostazol and GBE, given that there was a remarkable, but not statistically significant, increase in inhibition of platelet aggregation.

Pharmacokinetic and pharmacodynamic modeling of the antiplatelet and cardiovascular effects of cilostazol in healthy humans.

Cilostazol is an antiplatelet agent with vasodilating properties. It has been used to treat patients with peripheral ischemia, such as intermittent claudication. We used a pharmacokinetic-pharmacodynamic model to analyze the relation between the plasma concentration of cilostazol, the inhibitory effect of the drug on platelet aggregation, and the cardiovascular effects of the drug on healthy humans. A single oral dose of 100 mg cilostazol was administered to 20 healthy volunteers. Serial blood sampling and pharmacodynamic measurements were performed up to 48 hours thereafter. The effects of cilostazol on platelet aggregation, blood pressure, and heart rate were measured during the same period. The plasma concentration of cilostazol was measured with a validated HPLC method that entailed ultraviolet detection. The time courses of plasma cilostazol concentration, platelet aggregation, and cardiovascular effects were analyzed by means of pharmacokinetic-pharmacodynamic modeling with the program ADAPT II. The plasma concentration-time course followed a 2-compartment model. Mean peak concentration was 775 ng/ml approximately 3.65 hours after administration of cilostazol. The maximal effect on platelet aggregation was a 31.14% reduction 6.05 hours after administration. No significant difference in systolic blood pressure was found. The maximal increase in heart rate was 13.49%, whereas the maximal decrease in diastolic blood pressure was 29.51%. Both peak effects were detected approximately 6 hours after administration of the drug. Platelet aggregation and cardiovascular effects (change in diastolic blood pressure and heart rate) were analyzed with the effect-link sigmoid maximal effect model. This pharmacokinetic-pharmacodynamic model successfully described the relation between plasma concentration of cilostazol and the antiplatelet and cardiovascular effects of the drug.

Effects of a single local administration of cilostazol on neointimal formation in balloon-injured rat carotid artery

To elucidate if locally administered cilostazol, an inhibitor of cyclic AMP phosphodiesterase III, suppresses neointimal formation in balloon-injured carotid artery of the rat, 20 mg of cilostazol was topically applied using pluronic gel at the time of balloon injury. Rats were sacrificed 14 days after balloon injury to measure the extent of neointimal formation. Plasma and tissue concentrations of cilostazol were also measured at 1, 3, 7 and 14 days after topical application. The 5-bromo-2′-deoxyuridine (BrdU, a thymidine analogue) was given intraperitoneally to detect proliferation of smooth muscle cells in the injured media at 3 days after balloon injury. At 1 day after injury, plasma and tissue concentrations were 0.147±0.043 μg/ml and 1380 μg/g tissue. Although the plasma concentration of cilostazol was undetectable (<0.02 μg/ml), a significant amount of cilostazol (46 μg/g tissue) was still detected in the tissue at the site of application even after 2 weeks. The intimal area of the injured carotid after 2 weeks was significantly smaller in the cilostazol-treated group than in the gel-treated control group (0.06±0.01 vs 0.15±0.02 mm 2, P<0.001). BrdU-positive smooth muscle cells in the injured media after 3 days were also significantly fewer in the cilostazol-treated group than in the gel-treated control group (4.3±0.5 vs 9.1±0.9% of total cells, P<0.001). These results suggest that local administration of cilostazol using pluronic gel maintains a high concentration of the drug at the application site, has an anti-proliferative effect on smooth muscle cells, and may have potential for clinical therapeutic use for the prevention of restenosis following arterial intervention.