Mode of Action

The mechanism of action of Actilyse^® is similar to that of naturally occurring tissue plasminogen activator (t-PA).

Actilyse^® (recombinant tissue plasminogen activator, rt-PA) is a serine protease that, in the presence of fibrin, catalyses the conversion of plasminogen to plasmin.
Actilyse^® directly activates plasminogen and acts preferentially on fibrin bound plasminogen. It binds to plasminogen, which itself is bound to the fibrin netting of the blood clot at the lysine binding site, to form a ternary complex.
Actilyse^® activates this fibrin-bound plasminogen, converting it into plasmin.
Plasmin catalyses the breakdown of fibrin to its degradation products, resulting in breakup of the clot.
Actilyse^® is relatively inactive when infused into the systemic circulation; it has a low affinity for circulating plasminogen but a high affinity for fibrin-bound plasminogen, which it rapidly converts to plasmin resulting in highly effective local fibrinolysis with limited systemic effects.

Mechanism of action of Actilyse®