Following the clinical approval of novel oral anticoagulants as alternatives to 
the vitamin K antagonists, many additional novel oral anticoagulant drugs are 
currently in early and advanced stages of clinical development. The majority of 
the drugs in development belong to the class of direct factor Xa inhibitors (the 
-xabans). These include betrixaban, letaxaban, darexaban, eribaxaban, and 
LY517717. Another representative of the class of orally available direct 
thrombin inhibitors (the -gatrans) is known as AZD0837. Furthermore other 
coagulation factors with central roles within the coagulation cascade are 
currently investigated as potential targets for the development of novel oral 
anticoagulant drugs. Among those, the first direct oral factor IXa inhibitor 
TTP889 has entered the clinical phase of development. A short summary of novel 
oral anticoagulant currently in earlier stages of clinical development is 
provided.