- The subject requires concomitant treatment, in therapeutic doses, with anticoagulants such as warfarin or Coumadin-related agents, heparin, thrombin or FXa inhibitors, and antiplatelet agents (low-dose aspirin (≤81 mg/day), low-dose warfarin (≤1mg/day, and prophylactic low molecular weight heparin (LMWH) are permitted)