26 Clinical Trials for Various Conditions
This study builds, in part, upon preliminary results generated as part of the Pharmacogenomics Anti-Platelet Intervention (PAPI) Study (NCT00799396). The purpose of this investigation is to assess the impact of genetic variation in the carboxylesterase 1 (CES1) on response to clopidogrel as well as dual antiplatelet therapy (i.e. clopidogrel and aspirin), as assessed by ex vivo platelet aggregometry, in healthy Amish individuals. The investigators hypothesize that participants who carry alleles that modify the activity or expression of CES1 will have altered response to clopidogrel as well as dual antiplatelet therapy.
The purpose of this study is to understand how the drug rivaroxaban improves symptoms associated with peripheral artery disease.
The aim of this study is to determine how two different types of iodinated contrast media (CM) agents, low-osmolar ionic ioxaglate and iso-osmolar non-ionic iodixanol, affect specific markers of thrombogenesis and platelet function in patients undergoing coronary angiography, and if the use of bivalirudin, a direct thrombin inhibitor used during percutaneous coronary intervention (PCI), affects any contrast-related changes in thrombogenesis and platelet function.
The proposed PIVOTAL study will examine a panel of platelet/coagulation activity markers during the perioperative period. The goal is to develop a clinically useful assessment of platelet/coagulation activity for risk stratification that may ultimately serve as a target for therapeutic intervention. This study will enroll 200 patients with peripheral artery disease undergoing vascular surgery. PIVOTAL is funded by American Heart Association and is scheduled to begin enrollment in July 2013 for approximately two years.
The objective of the NeoPlaTT trial is to test whether, among extremely preterm infants born at 23 0/7 to 26 6/7 weeks' gestation, a lower platelet transfusion threshold, compared to a higher threshold, improves survival without major or severe bleeding up to 40 0/7 weeks' postmenstrual age (PMA).
The purpose is to conduct a dietary intervention study in which human participants will consume beverages sweetened with erythritol or aspartame, each for 2 weeks, in a randomized crossover design
The purpose of this pilot study is to determine how the anti-platelet drug, ticagrelor, impacts platelet mRNA splicing after a single loading dose in 10 healthy participants. These results will be valuable in that they will help inform our analysis of platelet RNA splicing after a thrombotic event.
TWILIGHT study is a multicenter RCT comparing treatment with ticagrelor alone versus ticagrelor plus aspirin in high-risk patients after PCI. All patients will receive DAPT (ticagrelor plus aspirin) for the initial 3 months post-PCI and then be randomized to either Ticagrelor alone OR Ticagrelor plus Aspirin DAPT. To investigate the pharmacodynamic effects of the two treatments in this trial, a 'Platelet Sub-study' will be conducted only at the Mount Sinai Medical Center. The sub-study will recruit randomized patients from the TWILIGHT Trial at Mount Sinai and conduct specialized blood tests at randomization and one month thereafter. The aim of the Platelet Sub-study is to compare the antithrombotic effects of Ticagrelor alone versus Ticagrelor plus Aspirin using an ex vivo model of thrombosis (Badimon Chamber).
This study evaluates the responsiveness of the Platelet Function Analyzer (PFA-100) to the effect of energy drinks on platelet function. Participants' will have blood drawn prior to and 60 minutes after ingesting 250ml of a commercially available sugar-free energy drink.
This study investigates the potential protective effects of fatty acid supplementation through inhibition of platelet activation. fatty acids (omega-3 and omega-6) will be evaluated for protection from agonist-mediated platelet activation in platelets from type 2 diabetics and healthy controls. Post-menopausal women with type 2 diabetes mellitus and healthy post-menopausal women will be treated with omega-3 and omega-6 fatty acid supplements to determine protection from platelet activation and thrombosis in this high risk population.
This study investigates the potential protective effects of altering fatty acid in the platelet as a method for prevention of platelet activation and thrombosis in type 2 diabetes mellitus. Fatty acids (omega-3 and omega-6) and their oxidized lipids will be evaluated for protection from agonist-mediated platelet activation in platelets from type 2 diabetics and healthy controls.
This research study examines the safety and feasibility of aspirin with or without Simvastatin in solid tumor patients at risk for VTE (Venous Thromboembolism - or blood clots - in the arms, lets, lungs, or other part of the body). One-fifth of all thrombotic (clotting) events occur in patients that have cancer. Changes in sP-selectin will be used as a measure of efficacy. We have chosen sP-selectin as the primary marker because of its role in hemostasis, because it is predictive of thrombosis in cancer patients and because of promising preliminary data. We expect that sP-selectin levels will be elevated in patients before therapy with aspirin and/or statin, but that these levels will fall significantly during treatment, rise during the observation phase, and fall during the second study period. Patients who take part in the study have been diagnosed with a solid tumor cancer and are considered to be intermediate to high risk for VTE. The standard of care is to give chemotherapy for solid tumors and treat clots which develop using blood thinners.
Acute coronary syndrome (ACS) patients treated with antiplatelet drugs who require coronary artery bypass grafting (CABG) surgery have to wait 5-7 days for the effects of the drugs to wean off. This treatment-devoid period leaves the patient vulnerable, therefore any means to shorten this period could be useful. The present study aims to investigate the possibility of reversing the antiplatelet effects of ticagrelor with the help of fresh donor platelets. Fresh platelets will be added to blood samples of treated patients in varying concentrations at specific timepoints to determine the time and amount of fresh platelets needed to normalize platelet reactivity in the treated samples.
The purpose of this observational research study is to determine when and why patients discontinue, interrupt, or disrupt the regimen of anti-platelet medications prescribed following stent implantation, and to examine the relationship between specific patterns of non-adherence and patient outcomes.
Patients who have undergone placement of coronary stents require dual antiplatelet therapy with Plavix and aspirin to prevent the serious complication of in-stent thrombosis. Some of these patients will require surgery while on dual antiplatelet therapy. This poses a challenge because being on Plavix is associated with higher risks of perioperative bleeding, but stopping Plavix puts patients at increased risk for in-stent thrombosis. Currently, the ACC/AHA guidelines recommend discontinuation of Plavix five days prior to surgery to prevent bleeding complications. However, there are no universal recommendations for preventing in-stent thrombosis. Some experts recommend the use glycoprotein IIb/IIIa inhibitors (short-acting antiplatelet agents) as "bridging therapy" during the high-risk perioperative period. Although these agents should be beneficial based on theory, there is currently no published data on their effectiveness for this purpose. The current study proposes to evaluate the value of Aggrastat (a short-acting intravenous platelet glycoprotein IIb/IIIa inhibitor) in decreasing the risk of in-stent thrombosis without increasing the risk of perioperative bleeding.
The objective of the GRAVITAS trial is to determine whether tailored anti-platelet therapy using the Accumetrics VerifyNow P2Y12 assay reduces major adverse cardiovascular events after drug-eluting stent implantation.
Blood contains red blood cells, white blood cells, and platelets, as well as a fluid portion termed plasma. We primarily study blood platelets, but sometimes we also analyze the blood of patients with red blood cell disorders (such as sickle cell disease), white blood cell disorders, and disorders of the blood clotting factors found in plasma. Blood platelets are small cell fragments that help people stop bleeding after blood vessels are damaged. Some individuals have abnormalities in their blood platelets that result in them not functioning properly. One such disorder is Glanzmann thrombasthenia. Most such patients have a bleeding disorder characterized by nosebleeds, gum bleeding, easy bruising (black and blue marks), heavy menstrual periods in women, and excessive bleeding after surgery or trauma. Our laboratory performs advanced tests of platelet function and platelet biochemistry. If we find evidence that a genetic disorder may be responsible, we analyze the genetic material (DNA and RNA) from the volunteer, and when possible, close family members to identify the precise defect.
PICOLO is a double blind placebo controlled phase II dose ranging, dose escalating study in patients of Blalock-Taussig age categories (neonates and infants/toddlers), to determine the dose providing inhibition of platelet aggregation similar to adults.
The objective of this study is to determine if the action of the drug called clopidogrel, that you will start taking, will be decreased by another drug called atorvastatin, that you will also start taking. Clopidogrel is an oral antiplatelet agent that has been shown to prevent strokes and heart attacks. Atorvastatin is a cholesterol lowering agent. Twenty adults 18-75 years of age requiring cholesterol-lowering agent and antiplatelet agent therapy will be recruited for this study during their cardiology clinic visitation. In one group, antiplatelet agent (clopidogrel) regimen will be administered first, then followed by cholesterol-lowering medication (atorvastatin). In the second group, atorvastatin will be administered first, followed by clopidogrel. A new test called the erythromycin breath test will be administered to you three times during the study to measure how your liver will metabolize these drugs. Blood samples will also be obtained to assess platelet function. The criteria for exclusion are patient refusal or inability to give written consent, patients with allergic reaction to erythromycin, patients with known bleeding problems, liver disease, significant lung disease kidney disease and pregnancy. Patients with psychiatric impairment and documented history of substance abuse will also be excluded from the study.
The purpose of this study is to see if indinavir plus two other anti-HIV drugs affect blood clotting in HIV-positive patients with hemophilia.
The availability of Sodium-glucose cotransporter-2 inhibitors (SGLT2-i) has dramatically altered the management of heart failure (HF) patients, independently of their ejection fraction and glycemic status. A meta-analysis of 57 studies comparing SGLT2-I monotherapy vs. placebo or active comparator showed reductions in major cardiovascular events, but no impact on atherothrombotic events. In fact, a non-significant increase in the risk for non-fatal stroke was observed. Similar trend observed in multiple trials indicate a SGLT2-i class effect. Sotagliflozin is the first dual SGLT1/2 receptor inhibitor, that was shown to significantly reduce atherothrombotic events compared with placebo in diabetic HF patients, suggesting that dual SGLT1/2 inhibitor may have additional properties vs. SGLT2-i. The hypothesis of this study is that dual SGLT1/2 inhibition by sotagliflozin improves thrombogenic profile (i.e. reduces thrombus formation), which could make it a safer and more effective treatment option for cardiovascular (CV) patients than SGLT2-i. To test the hypothesis, the researchers will compare the antithrombotic activity of sotagliflozin vs. empagliflozin in healthy volunteers using a randomized, cross-over study design, where each participant will receive both study treatments (sotagliflozin and empagliflozin) separated by a washout period. Treatment effects will be assessed by measuring ex vivo thrombus formation using the Badimon Perfusion chamber, platelet aggregation using Multiplate Analyzer, and Thromboelastometry using RoTEM Gamma. Study assessments will be performed before initiating (baseline/pre-treatment) and after completion of each treatment.
In parallel with the growth of American Thrombosis and Hemostasis Network's (ATHN) clinical studies, the number of new therapies for all congenital and acquired hematologic conditions, not just those for bleeding and clotting disorders, is increasing significantly. Some of the recently FDA-approved therapies for congenital and acquired hematologic conditions have yet to demonstrate long-term safety and effectiveness beyond the pivotal trials that led to their approval. In addition, results from well-controlled, pivotal studies often cannot be replicated once a therapy has been approved for general use.(1,2,3,4) In 2019 alone, the United States Food and Drug Administration (FDA) has issued approvals for twenty-four new therapies for congenital and acquired hematologic conditions.(5) In addition, almost 10,000 new studies for hematologic diseases are currently registered on www.clinicaltrials.gov.(6) With this increase in potential new therapies on the horizon, it is imperative that clinicians and clinical researchers in the field of non-neoplastic hematology have a uniform, secure, unbiased, and enduring method to collect long-term safety and efficacy data. ATHN Transcends is a cohort study to determine the safety, effectiveness, and practice of therapies used in the treatment of participants with congenital or acquired non-neoplastic blood disorders and connective tissue disorders with bleeding tendency. The study consists of 7 cohorts with additional study "arms" and "modules" branching off from the cohorts. The overarching objective of this longitudinal, observational study is to characterize the safety, effectiveness and practice of treatments for all people with congenital and acquired hematologic disorders in the US. As emphasized in a recently published review, accurate, uniform and quality national data collection is critical in clinical research, particularly for longitudinal cohort studies covering a lifetime of biologic risk.(7)
The purpose of this investigation is to evaluate when genetic variation in the carboxylesterase 1 (CES1) gene influences antiplatelet therapy response, as assessed by ex vivo platelet aggregometry, in healthy participants treated with clopidogrel and ticagrelor. We hypothesize that genetic variation in CES1 will significantly impact on-clopidogrel platelet aggregation while having a minimal effect in ticagrelor-treated subjects. Specific Aim: To conduct a prospective randomized crossover study of clopidogrel and ticagrelor in healthy individuals stratified by CES1 genotype. Participants will be recruited by CES1 genotype into a randomized crossover study of clopidogrel (75 mg daily for 7d) and ticagrelor (90 mg twice daily for 7d) with extensive phenotyping including ex vivo platelet aggregometry performed pre- and post-drug administration in order to assess the interaction of genotype and drug choice on on-treatment platelet function.
Despite the benefit of drug-eluting stents (DES) to reduce the need for repeat revascularization procedures, concerns regarding late stent thrombosis (ST) have led to recent guidelines advocating extended prescription of dual antiplatelet therapy (DAPT) with aspirin and a thienopyridine (clopidogrel or ticlopidine\]) beyond that described in the product labeling. Specifically, an advisory has recommended at least 1 year DAPT following treatment with DES in patients without contraindications. However, this recommendation was largely empiric and not based on any trial showing reductions in ST with long-term DAPT, nor are potential safety differences between DES considered. Further, no study has examined the balance in potential efficacy with long-term DAPT relative to an increased bleeding risk. A consistency across clinical trials involving the Endeavor DES has been very low rates of late myocardial infarction, cardiac death and ST. Unlike other DES, recent studies indicate that the Endeavor stent may permit more rapid and complete healing over stent struts in addition to restoring normal blood vessel function. Further, in patients treated with the Endeavor stent, long-term safety outcomes are similar through 3 years follow-up irrespective of whether patients were adherent to DAPT for durations of ≤ 6 months, 12 months or 24 months. In this study, long-term safety and effectiveness will be examined for patients treated with the Endeavor stent and assigned to DAPT for reduced duration of 6 months. If the study demonstrates safety and efficacy, it could influence treatment guidelines in favor of an abbreviated duration of DAPT for patients treated with the Endeavor stent. This would mean that should a bleeding complication or need or surgery arise less than 12 months post-PCI, patients treated with the Endeavor stent could stop DAPT after 6 months with reasonable estimate of safety. Furthermore, it is possible that patients who are currently denied DES due to known need for elective surgery could be treated with the Endeavor stent in cases where surgery can be temporarily delayed. Finally, it could be an additional option for patients who forgo treatment with DES in favor of bare metal stent (BMS) out of fear of possible bleeding with long-term DAPT. Finally, it is recognized that not all patients respond the same way to anti-platelet therapy. Recent studies have indicated that inherited genetic variations in the way the body metabolizes anti-platelet medications may be important determinants of responsiveness to thienopyridine therapy, and that such differences may also confer a higher likelihood of adverse outcome. Patients agreeing to the additional genetic sub-study will have a DNA sample taken at baseline to test for the presence of such genes related to antiplatelet therapy metabolism and effectiveness. The results of these tests could help the medical community to better understand individual variation in response to anti-platelet therapy and the role that genetics may play in determining the response. It is possible that the information gained could help physicians tailor DAPT on a patient by patient basis.
This study will evaluate thrombogenicity in patients undergoing left atrial appendage closure using the WATCHMAN device. Parameters of thrombosis and platelet function, as well as other bio-markers, will be measure before, during, and after WATCHMAN implantation at several follow up visits.
The goal of this clinical research study is to learn if eltrombopag can help to improve platelet counts in patients with low platelets after they have had a stem cell transplant. The safety of this drug will also be studied.