Fitusiran Disease Interactions

Fitusiran is associated with an increased occurrence of acute and recurrent gallbladder disease, including cholelithiasis and cholecystitis. In patients with a history of symptomatic gallbladder disease, consider alternative treatment for hemophilia. Monitor for signs and symptoms of acute/recurrent gallbladder disease. Consider interruption or discontinuation of fitusiran if gallbladder disease occurs.

Fitusiran is associated with an increased risk of thrombosis in patients with comorbidities that predispose to thrombosis and with persistent antithrombin (AT) activity less than 15%. Patients with established thrombophilia or a history of thrombosis were excluded from clinical studies. Ensure proper monitoring of AT activity with target of 15 to 35% to reduce the risk of thrombosis and monitor for thrombotic events. Interrupt therapy with fitusiran if thrombosis occurs.

Fitusiran should be avoided in patients with hepatic impairment (Child-Pugh A, B and C). Perform liver function tests prior to starting treatment and monitor as recommended by the manufacturer during therapy. If new or worsening liver test abnormalities occur, ensure appropriate diagnostic evaluation and medical management. Interruption or discontinuation of fitusiran may be required for elevations of ALT/AST (or for reoccurrence), or if jaundice secondary to hepatotoxicity occurs.