Beyond Direct Fibrinolysis: Novel Approaches to Thrombolysis

Fibrinolysis is a natural component of hemostasis in which a no-longer-needed clot is gradually dissolved to restore blood flow. Under pathological thrombotic conditions, this process can be pharmacologically enhanced to promote clot removal. However, thrombolytic therapy has limited efficacy and is associated with a risk of bleeding complications, including intracranial hemorrhage. Fibrinolysis targets only the fibrin-rich part of the thrombus, whereas a substantial fraction of the clot is enriched with non-fibrin components such as extracellular DNA, von Willebrand factor, and extracellular matrix proteins, including collagen, fibronectin, and laminin. These structural regions, which may constitute half or more of the clot volume, remain resistant to classical fibrinolytic agents. To overcome these limitations, recent therapeutic strategies aim to degrade these non-fibrin elements to improve thrombolytic efficacy and reduce adverse effects. In this review, we summarize current trends in pharmacological clot dissolution, discuss novel agents in clinical use and development, and outline how targeting non-fibrin components may influence the future of thrombolytic therapy.