Ostensibly Healthy Donors
Inclusion Criteria:
- Males and females age 21 years or older.
- Able and willing to provide written informed consent.
Exclusion Criteria:
- Hospitalization or doctor's visits within prior 30 days, except for routine checkup/physical examination.
- Use of antiplatelet therapy within the past 7 days, e.g. aspirin, clopidogrel, prasugrel, ticagrelor, cilostazol.
- Use of anticoagulant drugs within the past 7 days, e.g. heparin, bivalirudin, warfarin, rivaroxaban, and apixaban.
- Use of certain nonsteroidal anti-inflammatory drugs (NSAIDs) that inhibit COX-1 such as naproxen or ibuprofen within the past 3 days, unless confirmed to not inhibit platelet activity (such as celecoxib).
- History of anemia.
- Known thrombocytopenia (platelet count < 100,000/μL).
- Significant renal dysfunction or dialysis.
- History of platelet disorders e.g. von Willebrand factor deficiency, Glanzmann's thrombasthenia or Bernard-Soulier syndrome.
- History of hemophilia or bleeding disorders.
- Known active gastrointestinal disease including peptic ulcers, gastro-esophageal reflux disease (GERD), and hyperacidity.
- Currently participating in a study involving an investigational drug or compound known to affect coagulation or hemostasis.
- Subjects with significant past medical history as determined by the Investigator that would pose safety concerns or interfere with the study goals.
Antiplatelet Therapy Subjects
Inclusion Criteria:
- Males and females age 21 years or older.
- One of the following antiplatelet therapy regimens:
- Aspirin monotherapy:
- 81 mg or higher aspirin daily for 1 or more days
- Dual antiplatelet therapy:
- 81 mg or higher aspirin plus either 1) ≥300 mg clopidogrel loading dose within the prior 5 days followed by 75 mg daily clopidogrel, or 2) 75 mg daily clopidogrel daily for ≥5 days.
- 81 mg or higher aspirin plus either 1) 60 mg prasugrel loading dose within the prior 5 days followed by either 5 or 10 mg daily prasugrel, or 2) 5 or 10 mg daily prasugrel daily for ≥5 days.
- 81 mg aspirin plus either 1) 180 mg ticagrelor loading dose within the prior 5 days followed by 2x90 mg daily ticagrelor, or 2) 2x90 mg daily ticagrelor daily for ≥5 days.
- Able and willing to provide written informed consent.
Exclusion Criteria:
- Use of antiplatelet therapy other than aspirin, clopidogrel, prasugrel, or ticagrelor (e.g. cilostazol, abciximab, eptifibatide) within the past 7 days.
- Use of anticoagulant drugs within the past 7 days, e.g. heparin, bivalirudin, warfarin, rivaroxaban, and apixaban.
- Significant renal dysfunction or dialysis.
- Known thrombocytopenia (platelet count < 100,000/μL).
- History of platelet disorders e.g. von Willebrand factor deficiency, Glanzmann thrombasthenia or Bernard-Soulier syndrome.
- History of hemophilia or bleeding disorders.
- Females who are in the last trimester of pregnancy or are breastfeeding.
- Known active gastrointestinal disease including peptic ulcers, gastro-esophageal reflux disease (GERD), and hyperacidity.
- Currently participating in a study involving an investigational drug or compound known to affect coagulation or hemostasis.
- Subjects with significant past medical history as determined by the Investigator that would pose safety concerns or interfere with the study goals.
Von Willebrand Disease Subjects
Inclusion Criteria:
- Males and females age 21 years or older.
- Prior diagnosis of von Willebrand disease type 1, 2A, 2B, 2M, or 3
- Able and willing to provide written informed consent.
Exclusion Criteria:
- Prior diagnosis of von Willebrand disease type 2N
- Use of antiplatelet therapy besides aspirin within the past 14 days.
- Use of anticoagulant drugs within the past 14 days, e.g. heparin, bivalirudin, warfarin, rivaroxaban, and apixaban.
- Use of certain nonsteroidal anti-inflammatory drugs (NSAIDs) that inhibit COX-1 such as naproxen or ibuprofen within the past 7 days, unless confirmed to not inhibit platelet activity (such as celecoxib).
- Significant renal dysfunction or dialysis.
- Known thrombocytopenia (platelet count < 100,000/μL).
- Currently participating in a study involving an investigational drug or compound known to affect coagulation or hemostasis.
- Subjects with significant past medical history as determined by the Investigator that would pose safety concerns or interfere with the study goals.