27 Clinical Trials for Various Conditions
This study will involve healthy volunteers and patients with Type 2 diabetes. Eligible healthy volunteers will be invited to enroll into one of two protocols (A or B) and eligible patients with diabetes will be enrolled into protocol A.
Purpose of this study is to compare the reversal responses of 4°C cold stored platelets (CSP) versus 7 day, 22°C room temperature stored platelets (RTP) when given to healthy adult subjects who have received a loading dose of aspirin antiplatelet therapy.
ASA inhalation powder is an inhaled nonsteroidal anti-inflammatory drug-device combination that has been developed to reduce the risk of vascular mortality in patients with suspected acute myocardial infarction (MI), an FDA approved indication for oral formulations of aspirin. The primary goal of study OTP-P0-926 is to collect pharmacokinetic (PK)and pharmacodynamics (PD) pilot data to determine onset and extent of aspirin response after administration of varying doses of inhaled ASA (50-100mg) and 162 mg Non-Enteric-Coated Chewable ASA. PD will be assessed using standard methods to measure platelet inhibition by aspirin including platelet aggregation, serum thromboxane,and urinary thromboxane. Furthermore, the pharmacokinetics (PK) of ASA will be determined and compared to PD measurements. Results of this pilot study will guide dosing in a subsequent larger Phase II study.
One of the most common ways for preventing coronary heart disease (CHD) is to take aspirin or clopidogrel. However, studies have shown that not all people respond to these medications. The variance in treatment response may be linked to genetics. This study will examine the effects of aspirin and clopidogrel in a population whose genes are well known in order to determine the role that genes play in treatment responses.
Background: Antithrombotic therapy in the context of treatment related thrombocytopenia (i.e. low levels of platelets) is not uncommon. Guidelines are based upon a paucity of retrospective data and focus on the scenario of cancer associated venous thrombosis and low molecular weight heparin treatment. Even less is known regarding direct oral anticoagulants, antiplatelet therapy, or anticoagulation prescribed for other indications. Aims: The study aims are to evaluate how physicians manage anticoagulant and antiplatelet medication in patients with hematological malignancy and thrombocytopenia, and to assess the frequency of bleeding and thrombosis. Additional aims are to assess how management changes affect drug activity and blood clotting (coagulation), and to evaluate the use of platelet transfusions. Design: The investigators plan a multinational prospective registry of patients admitted to the inpatient hematology department or outpatient clinic at one of the study centers. Patients with hematological malignancies, platelets below 50 X 109/L, and anticoagulant and/or antiplatelet medication will be studied. Patients will be enrolled when the combination of antiplatelet/anticoagulant medication and thrombocytopenia is first detected. Patients will be followed until 30 days after the baseline study visit (which occurs 30 days after enrollment or when platelets \< 50\*109/L, whichever come first) or death. Patients will be indexed at the time of baseline visit. Patients will be excluded from study analysis if one of the following events occurs before study index: Withdrawal of consent, death, clinically-relevant non-major bleeding or the composite primary outcome. Risk factors for bleeding and thrombosis will be recorded at baseline. Parameters from routine blood tests will be recorded throughout the study. During the study major bleeding events and thrombosis will be recorded. Investigational blood tests assessing coagulation and drug activity will be drawn at baseline (=study index). Throughout the study all management decisions regarding antithrombotic therapy, including platelet and red blood cell transfusion, will be recorded. This is an observational study and management will be solely at the discretion of the physician. Analysis: The investigators will first look at the frequency of either bleeding or thrombosis according to the type of management strategy and evaluate the platelet threshold at which a given management strategy is employed. At the next stage, in selected subgroups, the optimal management strategy with respect to bleeding/thrombotic risk, will be determined.
* The purpose of this study is to determine the level of inhibition of platelet activation of an approved thienopyridine(clopidogrel or prasugrel) and aspirin regimen in the setting of drug eluting coronary stent implantation. * In subjects with high residual levels of platelet reactivity after receiving either a maintenance or loading dose of either clopidogrel or prasugrel, a cross over of thienopyridine treatment to the alternate medication will occur. * The study tests the hypothesis that adequate platelet inhibition will occur in subjects who have high levels of platelet reactivity and are subsequently switched from clopidogrel to prasugrel(loading or maintenance dose) without increased episodes of bleeding or MACE events at discharge and 30 days post Percutaneous Coronary Intervention (PCI).
This study will randomize patients recently discharged from the hospital with a confirmed diagnosis of type 1 acute myocardial infarction (Thygesen et al. 2018) and having additional cardiovascular risk factors.
This is a multi-center, open-label study for eligible participants who were actively participating in the BPS-314d-MR-PAH-302 double-blind study (NCT01908699) at the time the study was concluded. This open-label extension (OLE) study will evaluate the safety, tolerability, and efficacy of long-term treatment with esuberaprost sodium tablets (Beraprost Sodium 314d Modified Release tablets).
Randomized controlled study to examine physician use of pharmacogenetic information in patients receiving antiplatelet medication after percutaneous coronary intervention (PCI).
The object of the study is to determine whether different doses of PZ-128, when added to standard medical care in persons undergoing cardiac catheterization/percutaneous coronary intervention, will increase the risk of bleeding. A secondary objective is to determine whether patients treated with PZ-128 have fewer cardiac events such as heart attack, bypass surgery or stroke compared with those persons treated with the standard of care.
To compare the effect of ticagrelor versus aspirin on the change in peak walking time, evaluated on the graded treadmill test, from one to 26 weeks post-revascularization in patients with peripheral artery disease who have undergone endovascular revascularization for moderate to severe claudication or ischemic rest pain.
The primary objective is to determine the pharmacodynamic effect of ticagrelor dosing (180mg LD/ 90mg BID) at 2, 4 hours and 14 days in stable Coronary artery disease (CAD) patients who exhibit high-on prasugrel platelet reactivity defined as Vasodilator Stimulated Phosphoprotein-Phosphorylation (VASP-P) \>50%.
This study is a Phase I, intravenous, single-dose escalation study to evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of PZ-128 (pepducin inhibitor of PAR1) in subjects with vascular disease or who have 2 or more coronary artery disease (CAD) risk factors.
Early stent thrombosis has been noted with increased frequency in acute coronary syndrome (ACS) patients undergoing percutaneous coronary intervention (PCI) who are treated with bivalirudin and clopidogrel. The brief half life of bivalirudin acting in concert with the delayed action of clopidogrel likely exposes patients to thrombosis during a vulnerable period of reduced antiplatelet effect in the immediate post stenting period. Combination therapy with bivalirudin and prasugrel is conceptually attractive as the more rapid onset of action of prasugrel could potentially significantly diminish the vulnerable period, likely reducing the potential for acute stent thrombosis. The trials which have documented the efficacy of prasugrel as compared to clopidogrel have, in general, not reported on patients in whom bivalirudin was utilized. Currently, in the United States, bivalirudin is the most commonly used adjunctive agent used during PCI. Using light transmission aggregometry, this study will examine the inhibition of platelet aggregation in patients randomized to treatment with clopidogrel vs prasugrel during the vulnerable period following the discontinuation of bivalirudin therapy. The investigators anticipate that this study will document significant enhancement of inhibition of platelet aggregation in patients randomized to prasugrel treatment.
Assess the pharmacodynamic effect of ticagrelor vs. Clopidogrel in American Indian patients with stable coronary artery disease.
It is standard treatment to take anti-platelet medication after cardiac catheterization and stent placement to help prevent the formation of blood clots that may cause heart attack or stroke. The most commonly used anti-platelet medicine is clopidogrel (Plavix®). However, researchers have found that people vary in their response to clopidogrel, in part because of differences in their genes. Prasugrel (Effient®)is another anti-platelet medication used to prevent clots. The genetic differences that affect clopidogrel response do not affect prasugrel response. Recently, the FDA added a warning to the label of clopidogrel to notify doctors and patients with certain genetic differences may not get the full benefit from clopidogrel. Despite this, genetic testing for these variations is not usually done in standard medical practice. The purpose of this study is to see if patients with certain gene differences have fewer major cardiac events after stent placement if they are given anti-platelet therapy guided by their individual genetic type compared to standard anti-platelet therapy.
EDUCATE is a prospective, multi-center study designed to collect real-world safety and clinical outcomes in subjects receiving one or more Endeavor Zotarolimus-Eluting Stents and either clopidogrel and aspirin or prasugrel and aspirin as part of a dual antiplatelet therapy (DAPT) drug regimen.
This study is a sub-study of GRAVITAS (clinicaltrials.gov identifier NCT00645918). The purpose of this study is to assess which genes influence residual platelet reactivity on standard dose clopidogrel therapy, and also to determine whether certain genes influence the incremental change in platelet reactivity with high-dose clopidogrel maintenance dosing in patients who have high residual platelet reactivity on standard dosing.
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.
Gastroduodenal ulcers are extremely common in the community today. Though much has been written and observed concerning how ulcers form, not much has been described in the human model concerning how these ulcers heal. As numerous patients already suffer from gastrointestinal ulcers, further clarification of ulcer healing would be valuable in the treatment and management of these patients. The goal of this study is to investigate the effects of naproxen, aspirin, celecoxib, and clopidogrel on biopsy-induced gastroduodenal lesions in order to elucidate the mechanisms of ulcer healing. This single site, single-blind, randomized, placebo-controlled, one-week prospective study will examine ulcer healing through endoscopic, immunohistologic, and molecular PCR modalities.
This study will explore the effect of clopidogrel on coated-platelets in patients who are given a loading dose before diagnostic catheterization or percutaneous coronary intervention. We hypothesis that clopidogrel will reduce the percentage of platelets that are coated and therefore more hypercoagulable.
Clopidogrel is a medication that is used to decrease the ability of platelets to form blood clots. The theory has been proposed that, in patients with coronary artery disease or stroke, increased platelet function after discontinuation of clopidogrel therapy is associated with an increased clotting risk. However, this theory has never been rigorously tested. The goal of this research is to determine whether discontinuation of clopidogrel results in increased platelet function.
The purpose of this study is to evaluate whether a higher dosage of clopidogrel with aspirin (two doses) will decrease the risk of ischemic complications (cardiac death (CV death), myocardial infarction (MI), stroke) after a percutaneous coronary intervention (PCI).
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.
This is a multi-center convenience sample prospective study comparing the results of the Verify Now® Aspirin Test and PRUTest® Platelet Reactivity Tests with the Japan investigational reagents to reagents registered in Japan in the expected population receiving aspirin (ASA) and the P2Y12 inhibitor clopidogrel.
This study evaluates how aspirin, clopidogrel and ticagrelor work in people with chronic kidney disease (CKD) compared to people with normal kidneys. In the first part of the study, half of CKD participants will be randomly assigned to ticagrelor and aspirin, while the other half will be assigned to clopidogrel and aspirin in a blinded fashion. The treatment duration will be two weeks. After recruiting CKD participants the investigator will recruit controls with normal kidney function that will receive only ticagrelor and aspirin for two weeks.
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.