The Effect of Reloading Prasugrel in a Patient Who Has Already Received a Loading Dose (LD) of Clopidogrel (SWITCH 600/60)

SWITCH 600/60: The Effect of Reloading Prasugrel in a Patient Who Has Already Received a Loading Dose (LD) of Clopidogrel

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.

Study Overview

• Status: Completed
• Conditions: Acute Coronary Syndrome
• Intervention / Treatment: Drug: Prasugrel; Drug: 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.

• Study Type: Interventional
• Enrollment (Actual): 77
• Phase: Phase 4

Contacts and Locations

Study Locations

• United States
  • Alabama
    • Huntsville, Alabama, United States, 35801
      • The Heart Center
  • District of Columbia
    • Washington, District of Columbia, United States, 20010
      • Washington Hospital Center
  • Maryland
    • Baltimore, Maryland, United States, 21215
      • Sinai Center for Thrombosis Research
  • Missouri
    • Kansas City, Missouri, United States, 64111
      • Saint Luke's Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 73 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

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.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Patients who have received loading dose of clopidogrel	Drug: Prasugrel; Patients who have received 600 mg loading dose of clopidogrel will receive a reloading dose of 60 mg prasugrel; Drug: Prasugrel; Patients who have not received a loading dose of clopidogrel will receive a 60 mg loading dose of prasugrel.
Active Comparator: Patients who have not received loading dose of clopidogrel	Drug: Prasugrel; Patients who have received 600 mg loading dose of clopidogrel will receive a reloading dose of 60 mg prasugrel; Drug: Prasugrel; Patients who have not received a loading dose of clopidogrel will receive a 60 mg loading dose of prasugrel.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
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.	Average hospital stay is 24-48 hours.

Secondary Outcome Measures

Outcome Measure	Time Frame
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.	Average hospital stay is 24-48 hours.

Collaborators and Investigators

• Sponsor: Medstar Health Research Institute
• Investigators: Principal Investigator: Ron Waksman, MD, MedStar Washington Hospital Center

Publications and helpful links

General Publications

• 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.

Study record dates

Study Major Dates

• Study Start (Actual): October 1, 2010
• Primary Completion (Actual): January 1, 2014
• Study Completion (Actual): January 1, 2014

Study Registration Dates

• First Submitted: May 11, 2011
• First Submitted That Met QC Criteria: June 1, 2011
• First Posted (Estimate): June 3, 2011

Study Record Updates

• Last Update Posted (Actual): September 9, 2020
• Last Update Submitted That Met QC Criteria: September 4, 2020
• Last Verified: September 1, 2020

More Information

Terms related to this study

• Keywords: Prasugrel; Acute Coronary Syndrome; Clopidogrel
• Additional Relevant MeSH Terms: Myocardial Ischemia; Heart Diseases; Cardiovascular Diseases; Vascular Diseases; Acute Coronary Syndrome; Platelet Aggregation Inhibitors; Prasugrel Hydrochloride
• Other Study ID Numbers: SWITCH 600/60