Lack of specific antidotes is a major concern in intracerebral hemorrhage (ICH) 
related to direct anticoagulants including dabigatran (OAC-ICH). We examined the 
efficacy of idarucizumab, an antibody fragment binding to dabigatran, in a mouse 
model of OAC-ICH. Dabigatran etexilate (DE) dose-dependently prolonged diluted 
thrombin time and tail-vein bleeding time, which were reversed by idarucizumab. 
Pretreatment with DE increased intracerebral hematoma volume and cerebral 
hemoglobin content. Idarucizumab in equimolar dose prevented excess hematoma 
expansion for both DE doses. In more extensive ICH, idarucizumab significantly 
reduced mortality. Thus, idarucizumab prevents excess intracerebral hematoma 
formation in mice anticoagulated with dabigatran and reduces mortality.