Antiplatelet Effects Research Articles

Phase I results of both IV and oral administration for CG-0255: a novel fast-acting antiplatelet drug with a new activation pathway

Abstract Clopidogrel is an extremely widely used antiplatelet drug, but with serious shortcomings. It is a prodrug that depends critically on liver CYP oxidation enzyme CYP2C19 for activation to its active metabolite H4. However, large fractions of world population carry loss of function CYP2C19 alleles, ranging from a low ~21% in Latino to a strikingly high ~59% in east Asian population. Known as clopidogrel resistance, US FDA added a black box warning to clopidogrel label. Despite this issue, routine CYP2C19 screening for clopidogrel patients is not performed, putting many patients at risk. Clopidogrel is also slow to take effect and not amenable for IV formulation, limiting its clinical use in emergency. To overcome these issues, we have invented a novel antiplatelet drug CG-0255, which is the world’s first thioester prodrug with a new activation pathway. CG-0255 has been designed to require only abundantly present and widely distributed carboxylesterases for metabolizing to its active metabolite, which is identical to clopidogrel active metabolite H4 generated through CYP metabolism. Thus, CG-0255 completely bypasses the CYP metabolism and overcomes clopidogrel resistance. In addition, CG-0255 has a much faster onset of action and high solubility in water and has been formulated for both IV and oral administration. Here we report the results of an open label phase I study of CG-0255 oral tablets to assess safety, tolerability, pharmacodynamics (PK), and pharmacokinetics (PD: inhibition of platelet aggregation, IPA) in healthy volunteers. It was a single dose escalation study, 4 cohorts with 6 participants each given CG-0255 oral tablets at doses ranging from 2 to 10 mg. Clopidogrel was the positive control and given at 300 mg. Blood samples for PK/PD analysis were collected pre-dosing and at various time points post dosing. VerifyNow was used for IPA measurement. CG-0255 is generally safe and well tolerated. PK analysis shows fast and consistent conversion of CG-0255 to active metabolite H4. PD results indicate that CG-0255 IPA is dose-dependent, easily matching or surpassing that of clopidogrel 300 mg for all doses. At the highest 10 mg dose, CG-0255 IPA reaches over 90% in less than 30 minutes, well above that of clopidogrel. In addition, CG-0255 IPA shows minimum individual variations, and the antiplatelet effect is long lasting due to its irreversible binding to the P2Y12 receptor. These results are consistent with our earlier reported Phase I results for CG-0255 IV injection. In conclusion, CG-0255 is a novel, fast-acting and long-lasting antiplatelet drug. It shares identical metabolite H4 with clopidogrel but relies only on carboxylesterases for activation, overcoming the resistance and other issues associated CYP-based oxidation metabolism. As the only antiplatelet drug available for both IV and oral administrations, CG-0255 fills unmet medical needs and will greatly benefit patients and medical community.

Ticagrelor or prasugrel versus clopidogrel in patients with coronary heart disease

Abstract Introduction Antiplatelet therapy is pivotal in the management of coronary heart disease (CHD), especially after percutaneous coronary intervention (PCI). Clopidogrel has long been the cornerstone of dual antiplatelet therapy. However, newer agents like prasugrel and ticagrelor boast of faster onset of action and greater platelet inhibition, which may translate to improved outcomes. Purpose Our hypothesis is that prasugrel or ticagrelor are superior to clopidogrel in reducing cardiovascular mortality in chronic CHD patients. Methods We conducted a retrospective cohort study using the TriNetX network database, including patients with chronic CHD on dual antiplatelet therapy. A total of 1,420,165 patients on clopidogrel and 197,783 on prasugrel or ticagrelor were identified. We assessed the primary composite endpoint of cardiovascular mortality over a 5-year follow-up period, using event-free survival as our main outcome measure. Results The 5-year follow-up data revealed a significant difference in event-free survival between the groups. Patients on prasugrel or ticagrelor had a markedly higher event-free survival rate of 83.156% compared to 73.209% for those on clopidogrel. The Log Rank test showed a confidence interval of 1.544 to 1.592 with a highly significant p-value of <0.0001. Discussion The data suggest a clear benefit of prasugrel or ticagrelor over clopidogrel for event-free survival in CHD patients. This could be attributed to the more potent antiplatelet effects of these drugs, leading to reduced thrombotic events. Given the substantial sample size and robustness of the data, the findings advocate for a paradigm shift in the choice of more potent antiplatelet agents in clinical practice. Conclusion Our analysis supports the hypothesis that prasugrel or ticagrelor are associated with significantly lower cardiovascular mortality compared to clopidogrel in patients with chronic coronary heart disease.5-year Kaplan-Meier curves for mortality

PERSPECTIVES FOR THE USE OF PLANT RAW MATERIALS OF THE CLOVER MEADOW (TRIFOLIUM PRATENSE L.) IN PHARMACY

Background. The creation and registration of original medicines based on plant raw materials are becoming promising areas in pharmaceutical practice. Clover meadow (Trifolium pratense L.) has been used in folk medicine for a long time, due to the content of many biologically active substances with Therapeutic properties. It grows over large areas; extracts are easy to obtain from plant raw materials and have a certain economic attractiveness. In this regard, compounds extracted from meadow clover can be considered as potential precursors for the development of new promising pharmaceuticals. Aim. Carrying out a narrative review on the Perspectives of the use of biologically active substances extracted from the plant raw materials of meadow clover in pharmaceutical practice. Material and methods. The scientific publications of the PubMed biomedical research database are analyzed. Results. Meadow clover (Trifolium pratense L.) is a widespread perennial herbaceous plant belonging to the pharmacopoeia group. Extracts obtained from plant raw materials have a wide range of biological activity. The largest proportion of them are isoflavones, flavonoids, saponins, clovamides and phenolic acids. Isoflavones have a phytoestrogenic effect, and in this regard, they are successfully used in the treatment of diseases of the reproductive system. In addition, their anti-inflammatory, reparative properties have been proven; they can be used for the prevention and recovery of metabolic disorders. Flavonoids, saponins, clovamides and phenolic acids have antioxidant and antiplatelet effects. Conclusion. Among biologically active substances extracted from meadow clover, the greatest use in pharmacological practice was noted for isoflavones. At the same time, there are a few other potentially effective compounds with known medicinal properties. Their further study is required in order to create new original medicines

The effect of concurrent clopidogrel and omeprazole administration on clopidogrel metabolism and platelet function in healthy cats.

Some studies in humans show that the concurrent use of clopidogrel and omeprazole decreases plasma clopidogrel active metabolite (CAM) concentrations and clopidogrel antiplatelet effects. Whether this drug interaction occurs in cats is unknown. We hypothesized that administration of clopidogrel with omeprazole would decrease plasma CAM concentrations and decrease clopidogrel antiplatelet effects in healthy cats. Ten domestic cats. In this 2-sequence, 2-period, 2-treatment randomized crossover study, healthy cats were randomly assigned to receive clopidogrel only (18.75 mg PO q24h) or clopidogrel with omeprazole (1 mg/kg PO q12h) for 10 days, followed by a 2-week washout period, and then the opposite treatment for another 10 days. Blood was collected by jugular venipuncture on days 0, 5, and 10. Plasma CAM concentrations were measured using high-performance liquid chromatography-tandem mass spectrometry. Platelet function was evaluated using Plateletworks, Multiplate Analyzer, and Platelet Function Analyzer-100 (PFA-100). Multiplate Analyzer and PFA-100 detected no difference in platelet function between days or treatment groups. Plateletworks detected a significant difference (P < .001) in platelet function from day 0 to 5 and day 0 to 10 in both treatment groups but no difference between treatment groups. Plasma CAM concentrations were significantly lower on day 10 (P < .02) in cats receiving both medications versus clopidogrel only. Concurrent omeprazole and clopidogrel administration was associated with altered pharmacokinetics on day 10, but no difference in pharmacodynamics between the 2 treatment groups. The short-term use of clopidogrel and omeprazole does not seem to alter platelet function significantly.

Effects of selective serotonin reuptake inhibitors on platelet functions: a literature review.

Many epidemiological studies have evidenced an increased bleeding risk associated with selective serotonin reuptake inhibitors (SSRIs), yet the underlying mechanisms remain unclear. This review summarizes data on SSRIs' effects on platelet functions assessed with assays used in clinical practice and highlights the areas that deserve further investigation. Conflicting results of SSRI effects on platelet aggregation were observed irrespectively of the agonist used, the antidepressant drug or the study type. Alike, discrepant results were reported with flow-cytometry-based assays assessing either platelet surface glycoprotein levels, integrin activation, agonist-induced secretion of intraplatelet granule content or membrane anionic phospholipid exposure. Other tests may have detected a platelet function defect in SSRIs samples, however, results were largely inconsistent. Critical literature examination unveils very low certainty of evidence on potential SSRI effect on platelet functions. Findings are often inconsistent even when similar methods are used, most likely because of differences in study design, included patients (age, comorbid conditions), SSRIs' type and dose, uncontrolled confounding factors, and statistical analysis power. Further studies are needed to disentangle any intrinsic antiplatelet effect of SSRIs and the multiple confounding factors, mainly the depression control itself and the degree of platelet SERT inhibition.

Pharmacological effects of small molecule BCR-ABL tyrosine kinase inhibitors on platelet function.

Tyrosine kinase inhibitors (TKIs) targeting the BCR-ABL fusion protein, such as imatinib (Gleevec), have revolutionized targeted cancer therapies. However, drug resistance and side effects, particularly those affecting hemostasis, continue to pose significant challenges for TKI therapies. As tyrosine kinases serve pivotal roles in platelet hemostatic function, we investigated the potential impact of both established and emerging ABL TKIs on human platelet activities ex vivo Our study included standard-of-care agents (e.g., imatinib and nilotinib), and second-generation ABL inhibitors including ponatinib and bosutinib designed to mitigate drug resistance. Additionally, we explored the effects of allosteric inhibitors targeting the myristoyl pocket of ABL (e.g., asciminib and GNF-2), and novel agents in preclinical development, including ELVN-919, which uniquely exhibits high specificity for the ABL kinase active site. Our findings reveal that while ABL inhibitors such as ponatinib and bosutinib impede platelet activity, highly specific new-generation ABL inhibitors, including first-in-class therapeutics, do not impact platelet function ex vivo Overall, these new insights around the effects of ABL TKIs on platelet function could inform the development of targeted therapies with reduced hematologic toxicities. Significance Statement This study examines the effects of clinically relevant small molecule BCR-ABL tyrosine kinase inhibitors (TKIs) on platelet activity. This analysis includes first-time assessments of agents such as asciminib and ELVN-919 on human platelet function ex vivo, alongside established therapies (e.g., imatinib, ponatinib) with well-characterized effects on platelet function, to discern potential anti-platelet and other effects of BCR-ABL TKIs and inform clinical safety.

Unbiased High-Throughput Screening of Drug-Repurposing Libraries Identifies Small-Molecule Inhibitors of Clot Retraction

Platelet clot retraction, the ultimate phase of platelet thrombus formation, is critical for clot stabilization. It requires functional αIIbβ3 receptors, fibrin, and the integrated actions of the actin-myosin contractile and cytoskeletal systems. Disturbances in clot retraction have been associated with both bleeding and thrombosis. We recently demonstrated that platelets treated with the αIIbβ3 antagonist peptide RGDW, which eliminates fibrinogen-mediated platelet aggregation, are still able to retract clots. We have exploited this observation to developed an unbiased, functional high-throughput assay to identify small molecule inhibitors of fibrin-mediated clot retraction adapted for a 384-well plate format. We tested 9,710 compounds from drug-repurposing libraries (DRL’s). These libraries contain compounds that are either FDA-approved or have undergone preclinical/clinical development. We identified 27 compounds from the LOPAC library as inhibitors of clot retraction of which 14 are known inhibitors of platelet function. From the DRL we identified 135 compounds (1.6% hit rate). After extensive curation, these compounds were categorized based on the activity of their reported target. Multiple kinase and phosphodiesterase inhibitors with known antiplatelet effects were identified, along with multiple deubiquitination and receptor inhibitors, as well as compounds that have not previously been reported to have antiplatelet activity. Studies of one of the deubiquitination inhibitors (degrasyn) suggests that its effects are downstream of thrombin-induced platelet-fibrinogen interactions and thus may permit the separation of platelet thrombin-induced aggregation-mediated events from clot retraction. Additional studies of the identified compounds may lead to novel mechanisms of inhibiting thrombosis.

8539 Curcumin a Double Edged Sword: A Case of Curcumin Induced Pituitary Macroadenoma Apoplexy

Abstract Disclosure: P. Balozian: None. D. Alfakara: None. M. Linz: None. &amp;lt;Curcumin, the active component of turmeric, exerts numerous beneficial anti-inflammatory, antiplatelet, and anticoagulant effects. Recent literature has shown however that curcumin inhibits proliferation and induces apoptosis of pituitary cells. Despite these findings, there are limited clinical cases reporting an association between curcumin and pituitary adenoma apoplexy.We report the case of a 39-year old G9P6A3 female with Hashimoto’s disease and class II obesity who presented with a constant bifrontal excruciating headache, blurry vision, photophobia, and nausea. She also had fatigue and amenorrhea for two years. Her exam showed normal vitals, decreased visual acuity, diplopia, and bitemporal hemianopsia. Data showed a serum prolactin of 69 ug/L , plasma IGF-1 of 133 ng/ml (Z score -0.4), TSH of 2.58 with a free T4 of 0.47 ng/dl [0.61-1.12 ng/dL], a random cortisol of 12.7 mcg/dl despite her stress and pain, ACTH of 27 pg/ml, DHEA-S of 46 mcg/dl, an LH of 0.5 IU/L, and an FSH of 4mIU/ml with an estradiol of 25 pg/ml. MRI of the pituitary revealed a 1.8 cm macroadenoma with a mass effect on the overlying optic chiasm and a T1 intrinsic hyperintense signal indicative of a hemorrhagic component. She was given IV dexamethasone for 24 hours then underwent transsphenoidal resection of the hemorrhagic tumor that resulted in rapid resolution of headaches and visual symptoms. She was not given any glucocorticoids during or after surgery. Labs immediately after surgery revealed a prolactin of &amp;lt;1ug/L and a cortisol of 26.7 mcg/dl. Pathology showed corticotroph tumor with hemosiderin deposition with a 4.2% Ki67 and negative ACTH immunostaining. On medication review, patient had been taking large doses of curcumin. In the absence of other recent precipitating factors, it was highly likely that she had curcumin-triggered apoplexy of a pituitary macroadenoma. Most recent bloodwork, about 20 months from presentation, revealed a serum prolactin of 5.0 ug/L, IGF-1 of 123ng/mL (Z score -0.6), TSH of 0.97 mIU/L with a free T4 of 0.85 ng/dL, a random cortisol of 5.3 ug/dL, ACTH of 18.2 pg/mL, DHEA-S of 94 ug/dL, LH of 2.5 IU/L, FSH of 4.3 IU/L, and an estradiol of 45 pg/mL. Regular menstrual cycles had resumed. Headaches, nausea, and vision abnormalities completely resolved.The case illustrates the need to identify any herbal remedies and supplements a patient is taking, particularly turmeric, as supplements may contribute to increased bleeding tendency of an already existing adenoma. The case also emphasizes the potential rapid recovery of pituitary function after surgical resection of an apoplectic pituitary tumor.&amp;gt; Presentation: 6/3/2024

The first in-human study to evaluate the antiplatelet properties of the clopidogrel conjugate DT-678 in acute coronary syndrome patients and healthy volunteers.

DT-678 is a novel antiplatelet prodrug, capable of releasing the antiplatelet active metabolite of clopidogrel (AM) upon exposure to glutathione. In this study, we investigated factors responsible for clopidogrel high on-treatment platelet reactivity (HTPR) in acute coronary syndrome (ACS) patients and evaluated the capacity of DT-678 to overcome HTPR. A total of 300 consecutive ACS patients naive to P2Y12 receptor inhibitors were recruited and genotyped for CYP2C19 alleles. Blood samples were drawn before and after administration of 600-mg clopidogrel. Platelet reactivity index (PRI) and plasma AM concentrations were determined and grouped according to their CYP2C19 genotypes. DT-678 was applied ex vivo to whole blood samples to examine its inhibitory effects. To further examine the antiplatelet effectiveness of DT-678 in vivo, 20 healthy human subjects were recruited in a Phase I clinical trial, and each received a single dose of either 3-mg DT-678 or 75-mg clopidogrel. The pharmacokinetics and pharmacodynamics in different CYP2C19 genotype groups were compared. Statistical analyses revealed that CYP2C19 genotype, body mass index, hyperuricaemia, and baseline PRI were significantly associated with a higher risk of clopidogrel HTPR in ACS patients. The addition of DT-678 ex vivo decreased baseline PRI regardless of CYP2C19 genotypes, overcoming clopidogrel HTPR. This observation was further confirmed in healthy volunteers receiving 3mg of DT-678. These results suggest that DT-678 effectively overcomes clopidogrel HTPR resulting from genetic and/or clinical factors in Chinese ACS patients, demonstrating its potential to improve antiplatelet therapy.

Aspirin's Antiplatelet Effects Promote Arteriovenous Fistula Maturation in Hemodialysis Patients: A Systematic Review

Background: Arteriovenous fistula (AVF) is the preferred vascular access for hemodialysis, offering superior long-term patency and lower infection rates compared to other options. However, AVF maturation remains a significant challenge. This systematic review aims to evaluate the efficacy of aspirin in promoting AVF maturation and preventing failure in hemodialysis patients. Methods: A comprehensive search of electronic databases, including ScienceDirect, SpringerLink, PubMed, Cochrane, and ProQuest, was conducted from 2014 to 2024. Studies investigating the impact of aspirin on AVF maturation and failure were included. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Results: Five studies met the inclusion criteria, encompassing a total of 982 participants. Four studies indicated that aspirin significantly enhanced AVF maturation by increasing flow volume and promoting the development of a robust fistula. However, one study found that aspirin did not significantly reduce the risk of thrombosis or AVF failure. Conclusion: Aspirin appears to be a promising adjunct therapy for promoting AVF maturation in hemodialysis patients. Its antiplatelet effects, primarily through cyclooxygenase inhibition and reduced platelet activation, contribute to improved flow volume and fistula maturation. While the evidence for aspirin's role in preventing AVF failure is mixed, its potential benefits in enhancing maturation warrant further investigation.

Anti-platelet Effects of Artemisinin through Regulation of Cyclic Nucleotide on Collagen-induced human Platelets

Anti-platelet Effects of Artemisinin through Regulation of Cyclic Nucleotide on Collagen-induced human Platelets

Multicenter retrospective cohort study demonstrates superior safety profile of indobufen over aspirin for Post-CABG antiplatelet therapy.

Coronary artery bypass grafting (CABG) is essential for treating coronary artery disease, with postoperative aspirin crucial to prevent graft restenosis. However, its gastrointestinal side effects may limit tolerability in some patients. Indobufen presents a potential alternative, but its safety and efficacy need further validation. This study aimed to compare the efficacy and safety of indobufen versus aspirin in patients' post-CABG. This retrospective observational study included 39 patients who underwent CABG at two centers from January to December 2023. Patients were retrospectively assigned to two groups based on the antiplatelet therapy they received: the indobufen group (n = 19) and the aspirin group (n = 20). The primary endpoint was a composite of non-fatal myocardial infarction, stroke, and revascularization due to acute coronary syndrome in the intention-to-treat population. Postoperative data on platelet count, hemoglobin, D-dimer, activated partial thromboplastin time (APTT), and hospital stay length were collected. Transfusion rate, bleeding, thrombotic events, and gastrointestinal adverse reactions were compared between the two groups. Over the 8-to-18-month follow-up period, 5 patients (25%) in the aspirin group reached the primary endpoint, while none in the indobufen group did, a difference that was statistically significant (p = 0.02). Although the rates of non-fatal myocardial infarction, revascularization, stroke, and thrombotic events were higher in the aspirin group, these differences did not reach statistical significance. Importantly, the total bleeding events were markedly lower in the indobufen group (15.79% vs. 55%, p = 0.011), with major bleeding events also significantly reduced in the indobufen group (0% vs. 20%, p = 0.04). Both groups showed no significant differences were observed in postoperative hospital stay, hemoglobin, and D-dimer levels between the groups. However, the indobufen group demonstrated significantly lower platelet count and APTT. The average daily cost of indobufen was 27.8 times higher than that of aspirin. Indobufen demonstrates a comparable antiplatelet effect to aspirin and offers significant advantages in reducing gastrointestinal adverse reactions and bleeding risk. It can be considered a preferable alternative for patients who cannot tolerate or have contraindications to aspirin. Further large-scale clinical trials are needed to confirm its potential as the first-choice antiplatelet therapy post-CABG.

Exploring Aspirin's Potential in Cancer Prevention: A Comprehensive Review of the Current Evidence.

Aspirin, traditionally recognized for its analgesic, anti-inflammatory, antipyretic, and antiplatelet effects, has recently attracted attention for its potential role in cancer prevention. Initially studied for cardiovascular disease prevention, emerging evidence suggests that aspirin may reduce the risk of certain cancers, particularly colorectal cancer (CRC). This narrative review integrates findings from early studies, animal models, epidemiological data, and clinical trials to evaluate aspirin's efficacy as a chemopreventive agent. Aspirin's anticancer effects are primarily attributed to its cyclooxygenase (COX) enzyme inhibition, which decreases prostaglandin E2 (PGE2) levels and disrupts cancer-related signaling pathways. While epidemiological studies support an association between aspirin use and reduced cancer incidence and mortality, especially for CRC and potentially for breast (BC) and prostate cancers (PCa), the risk of adverse effects, such as gastrointestinal (GI) and intracranial bleeding, complicates its use and warrants careful consideration. The decision to use aspirin for cancer prevention should be individualized, balancing its therapeutic benefits against potential adverse effects. It also underscores the necessity for further research to refine dosage guidelines, assess long-term impacts, and explore additional biomarkers to guide personalized cancer prevention strategies.

Acetylsalicylic acid and dihydroartemisinin combined therapy on experimental malaria-associated acute lung injury: analysis of lung function and the inflammatory process

BackgroundSevere malaria can cause respiratory symptoms, which may lead to malaria-acute lung injury (MA-ALI) due to inflammation and damage to the blood-gas barrier. Patients with severe malaria also often present thrombocytopenia, and the use of acetylsalicylic acid (ASA), a commonly used non-steroidal anti-inflammatory drug with immunomodulatory and antiplatelet effects, may pose a risk in regions where malaria is endemic. Thus, this study aimed to investigate the systemic impact of ASA and dihydroartemisinin (DHA) on ALI induced in mice by Plasmodium berghei NK65 (PbNK65).MethodsC57BL/6 mice were randomly divided into control (C) and PbNK65 infected groups and were inoculated with uninfected or 104 infected erythrocytes, respectively. Then, the animals were treated with DHA (3 mg/kg) or vehicle (DMSO) at the 8-day post-infection (dpi) for 7 days and with ASA (100 mg/kg, single dose), and analyses were performed at 9 or 15 dpi. Lung mechanics were performed, and lungs were collected for oedema evaluation and histological analyses.ResultsPbNK65 infection led to lung oedema, as well as increased lung static elastance (Est, L), resistive (ΔP1, L) and viscoelastic (ΔP2, L) pressures, percentage of mononuclear cells, inflammatory infiltrate, hemorrhage, alveolar oedema, and alveolar thickening septum at 9 dpi. Mice that received DHA or DHA + ASA had an increase in Est, L, and CD36 expression on inflammatory monocytes and higher protein content on bronchoalveolar fluid (BALF). However, only the DHA-treated group presented a percentage of inflammatory monocytes similar to the control group and a decrease in ΔP1, L and ΔP2, L compared to Pb + DMSO. Also, combined treatment with DHA + ASA led to an impairment in diffuse alveolar damage score and lung function at 9 dpi.ConclusionsTherapy with ASA maintained lung morpho-functional impairment triggered by PbNK65 infection, leading to a large influx of inflammatory monocytes to the lung tissue. Based on its deleterious effects in experimental MA-ALI, ASA administration or its treatment maintenance might be carefully reconsidered and further investigated in human malaria cases.

Antiplatelet Effect of Low-Dose Prasugrel in Elderly Patients Undergoing Percutaneous Coronary Interventions.

Low-dose prasugrel (5 mg) has been proposed for patients with Acute Coronary Syndrome (ACS) and advanced age or low body weight. However, the routine use of dose-adjusted prasugrel in this high-risk subset of patients is still debated. This study aimed to assess the prevalence and predictors of HRPR among elderly patients treated with low-dose (5 mg) prasugrel to evaluate the routine use of dose-adjusted prasugrel in this high-risk subset of patients. We included 59 elderly patients (≥75 years) treated with Dual Antiplatelet Therapy (DAPT: acetylsalicylic acid (ASA) 100-160 mg + prasugrel 5 mg) after Percutaneous Coronary Interventions (PCI) and undergoing platelet function assessment (by whole blood impedance aggregometry) 30-90 days post-discharge. At a median follow-up of 43 days (interquartile range-IQR: 32-54), high-on treatment residual platelet reactivity (HRPR) occurred in 25 patients (42.4%), who displayed a greater body mass index (BMI) (p=0.02), lower levels of vitamin D (p=0.05) and were more frequently treated with nitrates (p=0.03). After multivariate analysis, BMI was the only independent predictor of prasugrel HRPR, and a BMI >26 was the best cut-off for predicting HRPR (adjusted Odds Ratio - OR=8.6, 95%CI: 2.2-33.9, p=0.002). Among elderly patients receiving DAPT after PCI, HRPR is common with low-dose prasugrel. A greater BMI, especially for values ≥26, is the only independent predictor of HRPR with prasugrel 5 mg.

Antiplatelet Reversal Is Not Associated With Decreased Progression of Intracranial Hemorrhage in Near-Isolated Traumatic Brain Injury: A Retrospective Clustered Analysis From Two Trauma Centers

IntroductionAntiplatelet agents (AAs) may increase the risk of intracranial hemorrhage (ICH). It is unclear whether reversal of antiplatelet effects (REV = desmopressin acetate [DDAVP] + Platelets) decreases ICH progression. The goal of the study was to determine whether REV was associated with decreased progression of ICH on repeat brain computed tomography (CT) scan. MethodsThis is a clustered study (November 2019 to March 2022) at two regionally distinct trauma centers (TCs) with differing standards of practice in patients with ICH, one reversal with DDAVP + Platelets (REV+) and the other no reversal with DDAVP + Platelets (REV−). Using electronic and manual chart review, data were collected on inpatients aged ≥ 18 y on preinjury AAs with CT proven ICH (abbreviated injury scale head ≥ 2) and no other abbreviated injury scale > 2 injuries, who had at least one repeat CT scan within 120 h of admission. ICH progression on repeat brain CT scan, mortality, and resource utilization were compared via univariate analysis (α = 0.05). ResultsOne hundred fourteen patients were enrolled: 72 REV+ at the first TC and 42 REV− at the second TC. REV+ group had fewer White patients and a lower proportion on preinjury aspirin but were otherwise similar. ICH progression rate was 24/72 (33.3%) for REV+ and 11/42 (26.2%) for REV− (P = 0.43). Isolated subarachnoid hemorrhage was the most common lesion, followed by isolated subdural hemorrhage. No patients required cranial surgery. All-cause mortality (expired + hospice) was 5/72 (6.9%) and 1/42 (2.4%), respectively (P = 0.29). ConclusionsIn this study of patients on preinjury AAs, REV was not associated with decreased ICH progression, lower mortality, or less resource utilization. These findings should be confirmed in a larger, prospective study.

Impact of P2Y12 Inhibitors on Thrombus Burden in ST-Segment Elevation Myocardial Infarction Patients Undergoing Primary Percutaneous Coronary Intervention

ABSTRACT: INTRODUCTION AND AIM: In this study, we aimed to investigate the effects of P2Y12 inhibitors administered at the time of admission to the emergency department in patients presenting with ST-segment elevation myocardial infarction (STEMI) and undergoing primary percutaneous coronary intervention on the thrombus score in the culprit lesion. MATERIALS AND METHODS: This retrospective study planned to compare the pre-procedural thrombus scores of 225 patients who presented with STEMI underwent primary percutaneous coronary intervention, and received different P2Y12 inhibitors within 2 hours after the onset of chest pain. RESULTS: A total of 225 patients were included in our study. Among them, 72 patients received clopidogrel, 85 received ticagrelor, and 68 received prasugrel as the P2Y12 inhibitor. The pre-procedural Grade 5 thrombus was significantly lower in the ticagrelor group compared to the other groups (Clopidogrel 77.78%, Ticagrelor 61.18%, Prasugrel 77.94%; p=0.017). CONCLUSIONS: In our study, ticagrelor among the pre-procedurally loaded P2Y12 inhibitors was found to be superior in terms of early thrombus intensity, and these results are thought to be associated with the early onset antiplatelet effect of ticagrelor. Keywords: ST segment elevation myocardial infarction, clopidogrel, prasugrel, ticagrelor, thrombus score

Effect of different anticoagulants and antiplatelets on intraoral bleeding time during professional oral hygiene session

ObjectivePatients with thromboembolic problems, prosthetic valves, or coagulation issues are commonly prescribed anticoagulants and antiplatelets. Anticoagulant and antiplatelet medication might constitute a challenge for dentists and dental hygienists since possible prolonged bleeding might interfere with dental procedures. The aim of the present study was to examine the bleeding durations associated with various anticoagulants and antiplatelets during professional dental hygiene sessions, utilizing a modified Ivy test adapted for the oral context.Materials and methodsNinety-three consecutive patients undergoing professional oral hygiene were recruited. Debridement during oral hygiene was performed using ultrasonic mechanical instrumentation, and bleeding sites were assessed and treated with gentle pressure using sterile gauzes. The time for bleeding cessation was recorded. Patients were categorized into six groups based on their drug intake, Control: no anticoagulants or antiplatelets DTI: direct thrombin inhibitors (dabigatran) AntiXa: directa factor Xa inhibitors (endoxaban, apixaban, rivaroxaban) VKA: vitamin K antagonists (warfarin, acenocoumarol) SAPT: single anti-platelet therapy (acetylsalicylic acid or clopidogrel) DAPT: dual anti-platelet therapy (acetylsalicylic acid and clopidogrel). Bleeding time was measured in seconds and mean values were assessed among the different groups. Differences between groups were investigated with Kruskal-Wallis test followed by Dunn’s post-hoc correction for multiple comparisons or two-way ANOVA followed by Dunnett post-hoc;ResultsControl patients presented the lowest bleeding time 50 s, followed by AntiXa (98), SAPT (105), DTI (120), DAPT (190) and VKA (203). A statistically significant difference was present among control and DTI (p = 0.004), VKA (p < 0.001), DAPT (p < 0.001).ConclusionsBased on the present outcomes, an increased risk of prolonged bleeding emerged in patients taking VKA and DAPT.Clinical significancebleeding did not interfere with the oral hygiene session The optimal period for dental treatment of these patients should be 2–3 h before the next dose, without the need to temporarily suspend the medication.

Temporal Effect of CYP3A4/5 Induction on Ticagrelor's Pharmacodynamic Effects: A Case Series.

Ticagrelor is contraindicated in combination with cytochrome P450 3A4 and 3A5 enzyme (CYP3A4/5) inducers due to increased clearance, causing diminished antiplatelet effects. The emergent nature of acute coronary syndromes (ACS) may preclude scrutinization of home medications before P2Y12 inhibitor administration. The purpose of this case series is to establish the temporal impact of CYP3A4/5 enzyme induction on ticagrelor's pharmacodynamic effect by utilizing VerifyNow platelet aggregation studies. This was a retrospective case series of three patients who were taking a CYP3A4/5-inducing medication and loaded with ticagrelor for ACS. The duration of ticagrelor's antiplatelet effect was dramatically shortened in the presence of background CYP3A4/5 induction. The offset of antiplatelet effect, defined by platelet reactivity units (PRU), was 10-24hours in the presence of CYP3A4/5 enzyme induction compared to the anticipated 36-48 hours. This was consistent across CYP3A4/5-inducing medications including carbamazepine, phenobarbital, and phenytoin. This study demonstrates rapid return of platelet function after a ticagrelor loading dose in the presence of CYP3A4/5-inducing medications. Monitoring of PRU every 6-12hours with subsequent loading with clopidogrel or prasugrel should be considered. Larger scale studies are warranted to confirm these results.

An integrated and rapid evaluation of Curcumae Radix from different botanical origins based on chemical components, antiplatelet aggregation effect and Fourier transform near-infrared spectroscopy

Curcumae Radix (CR) is a widely used traditional Chinese medicine with significant pharmaceutical importance, including enhancing blood circulation and addressing blood stasis. This study aims to establish an integrated and rapid quality assessment method for CR from various botanical origins, based on chemical components, antiplatelet aggregation effects, and Fourier transform near-infrared (FT-NIR) spectroscopy combined with multivariate algorithms. Firstly, ultra-performance liquid chromatography-photodiode array (UPLC-PDA) combined with chemometric analyses was used to examine variations in the chemical profiles of CR. Secondly, the activation effect on blood circulation of CR was assessed using an in vitro antiplatelet aggregation assay. The studies revealed significant variations in chemical profiles and antiplatelet aggregation effects among CR samples from different botanical origins, with constituents such as germacrone, β-elemene, bisdemethoxycurcumin, demethoxycurcumin, and curcumin showing a positive correlation with antiplatelet aggregation biopotency.Thirdly, FT-NIR spectroscopy was integrated with various machine learning algorithms, including Artificial Neural Network (ANN), K-Nearest Neighbors (KNN), Logistic Regression (LR), Support Vector Machine (SVM), and Subspace K-Nearest Neighbors (Subspace KNN), to classify CR samples from four distinct sources. The result showed that FT-NIR combined with KNN and SVM classification algorithms after SNV and MSC preprocessing successfully distinguished CR samples from four plant sources with an accuracy of 100%.Finally, Quantitative models for active constituents and antiplatelet aggregation bioactivity were developed by optimizing the partial least squares (PLS) model with interval combination optimization (ICO) and competitive adaptive reweighted sampling (CARS) techniques. The CARS-PLS model achieved the best predictive performance across all five components. The coefficient of determination (R2p) and root mean square error (RMSEP) in the independent test sets were 0.9708 and 0.2098, 0.8744 and 0.2065, 0.9511 and 0.0034, 0.9803 and 0.0066, 0.9567 and 0.0172 for germacrone, β-elemene, bisdemethoxycurcumin, demethoxycurcumin and curcumin, respectively. The ICO-PLS model demonstrated superior predictive capabilities for antiplatelet aggregation biotency, achieving an R2p of 0.9010, and an RMSEP of 0.5370.This study provides a valuable reference for the quality evaluation of CR in a more rapid and comprehensive manner.