Fitusiran

**Semantic type:** Pharmacologic Substance

**Definition:** A small-interfering RNA (siRNA) directed against the human glycoprotein antithrombin (AT), with potential coagulant activity. Upon subcutaneous administration of fitusiran, the siRNAs bind to AT mRNAs, which may result in the inhibition of translation of the AT protein. By preventing AT expression, the coagulation factor thrombin is increased and activated, which leads to the conversion of fibrinogen to fibrin, and thus clot formation. This reduces bleeding in hemophilia and rebalances hemostasis.

**Synonyms:** - ALN 57213 - ALN AT3SC - ALN-57213 - ALN-AT3SC - ALN57213 - ALNAT3SC - FITUSIRAN