Factor XI inhibitors may serve as hemostasis-sparing anticoagulants by uncoupling thrombosis from hemostasis, potentially offering a safer alternative for patients at high risk for bleeding.
Hemostasis and thrombosis are believed to be so intricately linked that any strategies that reduce thrombosis will have an inevitable impact on hemostasis. Consequently, bleeding is viewed as an unavoidable side effect of anticoagulant therapy. Emerging evidence suggests that factor XI is important for thrombosis but has a minor role in hemostasis. This information raises the possibility that anticoagulants that target factor XI will be safer than currently available agents. The authors provide a visual representation of the coagulation pathways that distinguishes between the steps involved in thrombosis and hemostasis to explain why factor XI inhibitors may serve as hemostasis-sparing anticoagulants. A safer class of anticoagulants would provide opportunities for treatment of a wider range of patients, including those at high risk for bleeding. Ongoing clinical studies will determine the extent to which factor XI inhibitors attenuate thrombosis without disruption of hemostasis.
“By uncoupling thrombosis and hemostasis, new anticoagulants targeting factor XI (FXI) can result in less bleeding compared with current options. This is feasible because FXI is essential for thrombus expansion but largely unnecessary for hemostasis.”
Hsu et al. (Sun,) conducted a review in Thrombosis and hemostasis. Factor XI inhibitors vs. Currently available anticoagulants was evaluated. Factor XI inhibitors may serve as hemostasis-sparing anticoagulants by uncoupling thrombosis from hemostasis, potentially offering a safer alternative for patients at high risk for bleeding.