去纤苷的注意事项有哪些？

Defibrotide (defiteli) is a mixture of single-stranded oligonucleotides with anti-thrombotic and fibrinolytic effects. In recent years, multiple clinical research results have shown that defibrotide is a safe and effective drug for preventing and treating HVOD after HSCT.

The mechanism of action of defibrotide has not been fully elucidated. In vitro, defibrinoside enhances the enzymatic activity of plasmin, which hydrolyzes fibrin clots. Studies evaluating the pharmacological effects of defibrotide on endothelial cells (ECs) have been primarily conducted in human microvascular endothelial cell lines.

In vitro, defibrinoside increases tissue plasminogen activator (t-PA) and thrombomodulin expression and decreases von Willebrand factor (vWF) and plasminogen activator inhibitor-1 (PAI-1) expression, thereby reducing EC activation and increasing EC-mediated fibrinolysis. Defibrotide protects ECs from chemotherapy, tumor necrosis factor-α (TNF-α), serum starvation, and perfusion-induced injury.

What are the precautions for defibrination?

1. Bleeding: Defibrinoside increases the activity of plasmin in vitro, and sputum may increase the risk of bleeding after hematopoietic stem cell transplantation (HSCT) in patients with VOD. Do not initiate defibrotide in patients with active bleeding. Monitor patients for signs of bleeding.

The concomitant use of defibrotide (defiteli) and a systemic anticoagulant or fibrinolytic therapy (excluding use for routine maintenance or central venous line reopening) may increase the risk of bleeding. Discontinue anticoagulants and fibrinolytics before defibrotide therapy, and consider delaying initiation of defibrotide administration until the effects of the anticoagulant have lessened.

2. Hypersensitivity reaction: Hypersensitivity reaction has occurred in less than 2% of patients treated with defibrotide. These reactions include rash, urticaria, and angioedema. One case of anaphylactic reaction was reported in a patient who had previously received defibrotide. Monitor patients for hypersensitivity reactions. Especially if there is a history of previous exposure. If a severe hypersensitivity reaction occurs, discontinue defibrotide, treat with standard medical care, and monitor until symptoms resolve.