Wikipedia
Betrixaban ( INN, codenamed PRT-054,021) is an anticoagulant drug which acts as a direct factor Xa inhibitor. It is potent, orally active and highly selective for factor Xa, being selected from a group of similar compounds for its low hERG affinity. Betrixaban has undergone human clinical trials for prevention of embolism after knee surgery, and prevention of stroke following atrial fibrillation, with promising results. Betrixaban is currently being studied in a human clinical trial for extended duration thromboprophylaxis to prevent venous thromboembolism in acute medically ill patients. Joint development with Portola was discontinued in 2011 by Merck. Betrixaban is now being developed by Portola Pharmaceuticals.