In order to strengthen its already robust position in the thrombosis market, Bayer HealthCare has licensed exclusive worldwide rights to develop and commercialise Isis Pharmaceuticals’ ISIS-FXIRx, an antisense Factor XI in Phase II development that is designed to prevent blood clots without significantly increasing the risk of bleeding. ISIS-FXIRx is a potential treatment option for those patients for whom currently available anticoagulants, including Bayer’s oral Factor Xa inhibitor Xarelto® (rivaroxaban), are rarely prescribed.