|- candidate number||21844|
|- NTR Number||NTR5114|
|- ISRCTN||ISRCTN no longer applicable|
|- Date ISRCTN created|
|- date ISRCTN requested|
|- Date Registered NTR||24-mrt-2015|
|- Secondary IDs||NL49455.029.14 2014-002928-27|
|- Public Title||Observing Platelet Activability in a Once daily vs. a More frequent Aspirin intake regimen
|- Scientific Title||Observing Platelet Activability in a Once daily vs. a More frequent Aspirin intake regimen
|- ACRONYM||THE OPA & OMA-TRIAL|
|- hypothesis||A twice daily intake regimen of aspirin provides a more stable inhibition within 24 hours after intake, compared to a once daily regimen.|
|- Healt Condition(s) or Problem(s) studied||Cardiovascular disease, Myocardial infarction, Angina Pectoris|
|- Inclusion criteria||- Outpatients being treated for stable cardiovascular disease by the cardiology department. |
- Stable cardiovascular disease defined as: coronary artery disease, peripheral vascular disease or previous myocardial infarction.
|- Exclusion criteria||- Active bleeding|
- Diabetes mellitus
- Thrombopathy (e.g. von Willebrand disease, Glanzmannís thrombasthenia and BernardĖSoulier syndrome)
- Any ischemic event or revascularization procedure (percutaneous coronary intervention or coronary artery bypass grafting) within the last six months.
- Alcohol intake the day before blood sampling.
- Non-compliance to the protocol
- Recent use of antiplatelet drugs, anticoagulants or drugs that are known to alter platelet function, other than aspirin (e.g. NSAIDís, tirofiban, eptifibatide, abciximab, beta-lactam antibiotics, dextran, SSRIís, clomipramine & amitriptyline, dipyridamole, verapamil, diltiazem , ginkgo biloba, ginseng, St Johnís wort).
|- mec approval received||yes|
|- multicenter trial||no|
|- control||Not applicable|
|- Type||2 or more arms, randomized|
|- planned startdate ||1-jun-2015|
|- planned closingdate||1-sep-2018|
|- Target number of participants||85|
|- Interventions||- Once daily intake regime 8.00 am, duration 10 days|
- Once daily intake regime 8.00 pm, duration 10 days
- Twice daily intake regime 8.00 am & pm, duration 10 days
|- Primary outcome||- PFA-200 parameters: closure time, flow slope, maximum rate of occlusion and area under the curve|
- Chrono-log LTA parameters: Amplitude of aggregation given in percentages and the area under the curve.
- VerifyNow parameter: PRU
- TBX2 serum levels.
|- Secondary outcome||Platelet- , reticulated platelet- , leucocyte count and haemoglobin level |
|- Timepoints||Measured after 10 days of every intake regimen|
|- Trial web site|
|- status||open: patient inclusion|
|- CONTACT FOR PUBLIC QUERIES|| Jeske (J.J.K.) van Diemen|
|- CONTACT for SCIENTIFIC QUERIES|| Jeske (J.J.K.) van Diemen|
|- Sponsor/Initiator ||VU University Medical Center|
(Source(s) of Monetary or Material Support)
|- Brief summary||Objective: Analyze whether a twice daily regimen is superior to a once daily regime of aspirin when it comes to inhibiting platelet aggregation in cardiovascular patients|
Study design: Single blinded, open label, randomized cross-overy study.
Study population: 75 outpatients from the cardiology department, taking 80 mg of acetylsalicylic acid once a day. 10 healthy subjects will be used to define baselines in the assays that are being used.
Intervention: Study participants will sequentially be allocated to three dosage regimens, A1, B, and C. The order of allocation will be decided via randomisation. Regimen A and B are designed to establish a baseline activability of the platelets under a once a day regime of acetylsalicylic acid. In regimen C participants are put on a twice daily dosage regimen. NB circadian rhythm has been taken into account. .
Main study parameters/endpoints: We will analyze whether a twice daily regimen is superior to a once daily regime of aspirin when it comes to inhibiting platelet aggregation in cardiovascular patients, as measured by the PFA-200, Chrono-log light transmission aggregometry, VerifyNow, and a TBX2 serum ELISA.
|- Main changes (audit trail)|
|- RECORD||24-mrt-2015 - 26-jun-2017|