Pharmacological actions of Tirofiban

Tirofiban is a reversible antagonist of fibrinogen binding to the GP IIb/IIIa receptor. This receptor is the major platelet surface receptor involved in platelet aggregation. Tirofiban dose- and concentration-dependent inhibition of isolated platelet aggregation when administered intravenously.

Tirofiban hydrochloride is a chemically synthesized non-peptide drug, which has two effects:

1) Antithrombotic through the inhibition of adenosine diphosphate (ADP), in vitro studies have shown that Tirofiban Hydrochloride dose-dependently inhibits human platelet aggregation in vitro induced by ADP, collagen, arachidonic acid, thromboxane analog U46619 and thrombin. However, it has no effect on platelet aggregation induced by ristocetin, and its selectivity is strong. Tirofiban tl/2 is about 2h, and about 65% is excreted through the kidney. In the study of recurrent stroke, it can significantly reduce the incidence of acute and subacute ischemic complications.

2) It can activate thrombin, and then selectively activate the adhesion of monocyte-platelet, cause the release of tissue factor, start blood coagulation, and promote the conversion of fibrinogen into fibrin. Therefore, the use of this drug after percutaneous transluminal coronary angioplasty (PTCA) can prevent the occurrence of bleeding and make it less adverse reactions. At the same time, Tirofiban Hydrochloride can be combined  with heparin and aspirin, which can significantly reduce adverse events such as cardiovascular complications and the incidence and mortality of myocardial infarction, and reduce refractory angina pectoris and cardiovascular diseases requiring repeated coronary angioplasty.