Which of the following is not a P2Y12 inhibitor: Eptifibatide (Integrilin), Clopidogrel (Plavix), Prasugrel (Effient), or Ticagrelor (Brilinta)?

From the Guidelines

Eptifibatide is not a P2Y12 inhibitor, whereas clopidogrel, prasugrel, and ticagrelor are all P2Y12 inhibitors. The key difference lies in their mechanism of action. Eptifibatide is a glycoprotein IIb/IIIa inhibitor, which blocks the final common pathway of platelet aggregation by preventing fibrinogen from binding to activated platelets 1. In contrast, clopidogrel, prasugrel, and ticagrelor are P2Y12 inhibitors that prevent platelet aggregation by blocking the P2Y12 receptor on platelets, specifically targeting ADP-mediated platelet activation 1.

Some key characteristics of these P2Y12 inhibitors include:

• Clopidogrel: irreversible inhibition, requires bioactivation, and has a delayed onset of effect 1
• Prasugrel: irreversible inhibition, requires bioactivation, and has a rapid onset of effect 1
• Ticagrelor: reversible inhibition, does not require bioactivation, and has a rapid onset of effect 1

Given the most recent and highest quality evidence, the correct answer is Eptifibatide, as it does not belong to the P2Y12 inhibitor class, unlike clopidogrel, prasugrel, and ticagrelor, which are all used in the management of acute coronary syndromes and have distinct pharmacological properties 1.

From the FDA Drug Label

Clopidogrel is an inhibitor of platelet activation and aggregation through the irreversible binding of its active metabolite to the P2Y12 class of ADP receptors on platelets. Prasugrel is an inhibitor of platelet activation and aggregation through the irreversible binding of its active metabolite to the P2Y12 class of ADP receptors on platelets. Ticagrelor is not mentioned in the provided drug labels, but based on general knowledge, it is also a P2Y12 inhibitor. Eptifibatide is a glycoprotein IIb/IIIa inhibitor, not a P2Y12 inhibitor.

The answer is: Eptifibatide 2, 3, 3.

From the Research

P2Y12 Inhibitors

The following are P2Y12 inhibitors:

• Clopidogrel
• Prasugrel
• Ticagrelor

Non-P2Y12 Inhibitors

The following is not a P2Y12 inhibitor:

• Eptifibatide, as it is a glycoprotein IIb/IIIa inhibitor, not a P2Y12 inhibitor 4, 5, 6, 7

Key Points

• Eptifibatide works by blocking the glycoprotein IIb/IIIa receptor, preventing platelet aggregation 4, 7
• Clopidogrel, prasugrel, and ticagrelor are oral P2Y12 inhibitors used in acute coronary syndrome 8
• Ticagrelor and prasugrel have been shown to reduce ischemic events and increase bleeding compared to clopidogrel 8