Clinical trial NCT01365221: The Effect of Reloading Prasugrel in a Patient Who Has Already Received a Loading Dose (LD) of Clopidogrel
Official title: SWITCH 600/60: The Effect of Reloading Prasugrel in a Patient Who Has Already Received a Loading Dose (LD) of Clopidogrel
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: PHASE4
Conditions: Acute Coronary Syndrome
Keywords: Acute Coronary Syndrome
Clopidogrel
Prasugrel
Lead sponsor: Medstar Health Research Institute
Sponsor class: OTHER
First posted: 2011-06-03
Enrollment: 77
Sex: ALL
Minimum age (years): 18
Maximum age (years): 75
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: NON_RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The primary objective of this study is to compare platelet reactivity between patients receiving a loading dose of clopidogrel and a reloading dose of prasugrel to patients receiving only a loading dose of prasugrel.

Detailed description: This is a prospective, open-label, non-randomized trial of approximately 260 patients with Acute Coronary Syndrome (ACS) undergoing percutaneous coronary intervention (PCI). In order to compare platelet reactivity, as assessed by the VerifyNow P2Y12 assay, we plan to recruit two study groups of interest:

1. Patients who have already received a 600 mg loading dose (LD) of clopidogrel in preparation for PCI will receive a loading dose of 60 mg of prasugrel.
2. Patients who have not received a LD of clopidogrel will receive a 60 mg LD of prasugrel prior to PCI.

A subset of 40 patients from each study group (80 patients total) will undergo additional platelet reactivity testing with the vasodilator stimulated phosphoprotein (VASP) assay.All patients will be followed throughout the duration of the hospital stay.

Eligibility criteria: Inclusion Criteria:

1. Patients age 18 or older, of both genders
2. Presenting with an ACS, defined as at least two of the following:

   Symptoms consistent with myocardial ischemia; ST segment elevation or depression of at least 1 mm in 2 or more contiguous leads on EKG; Cardiac troponin I level above the upper limit of normal.
3. An initial invasive strategy (e.g. early angiography) is planned.
4. No contraindications to prasugrel therapy.

Exclusion Criteria:

1. Known allergies to aspirin, clopidogrel, or prasugrel.
2. Patient known to be pregnant or lactating.
3. Patient with known history of bleeding diathesis, or currently active bleeding.
4. Platelet count \<100,000/mm3 at the time of enrollment.
5. Hematocrit \<25% at the time of enrollment.
6. On warfarin therapy at the time of PCI, or patient likely to require warfarin therapy post-PCI.
7. Received fibrinolytics within the past 48 hours.
8. Received a glycoprotein IIb/IIIa inhibitor within the past 48 hours, or if a strategy for PCI involving a glycoprotein IIb/IIIa inhibitor is planned.
9. Taking maintenance thienopyridine therapy in the previous 7 days.
10. Known blood transfusion within the preceding 10 days.
11. Patients treated with non-steroidal anti-inflammatory drugs (NSAIDS) within the previous 5 days.
12. Patients with known chronic liver disease.
13. Age greater than 75 years.
14. Body weight less than 60 kg.
15. History of stroke or transient ischemic attack.
16. Surgery planned within 1 month.
17. Patient likely to require coronary artery bypass grafting.
18. Any significant medical condition that, in the investigator's opinion, may interfere with the patient's optimal participation in the study.

Primary outcomes:
measure: The primary objective is to compare platelet reactivity, as assessed by the VerifyNow P2Y12 assay, between patients receiving a loading dose of clopidogrel and a reloading dose of prasugrel to patients receiving only a loading dose of prasugrel.
timeFrame: Average hospital stay is 24-48 hours.
Secondary outcomes:
measure: The secondary objective of this study is to describe rates of bleeding events associated with a loading dose of prasugrel in patients who have already received a loading dose of clopidogrel.
timeFrame: Average hospital stay is 24-48 hours.
Other outcomes:
Locations:
city: Huntsville
country: United States
facility: The Heart Center
state: Alabama
city: Washington
country: United States
facility: Washington Hospital Center
state: District of Columbia
city: Baltimore
country: United States
facility: Sinai Center for Thrombosis Research
state: Maryland
city: Kansas City
country: United States
facility: Saint Luke's Hospital
state: Missouri
Study officials:
affiliation: Medstar Health Research Institute
name: Ron Waksman, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Lhermusier T, Lipinski MJ, Drenning D, Marso S, Chen F, Torguson R, Waksman R. Switching patients from clopidogrel to prasugrel in acute coronary syndrome: impact of the clopidogrel loading dose on platelet reactivity. J Interv Cardiol. 2014 Aug;27(4):365-72. doi: 10.1111/joic.12139. Epub 2014 Jul 19.