NU172

NU172 is a 26-nucleotide DNA aptamer that functions as a direct thrombin inhibitor. It binds specifically to exosite I of human thrombin, thereby inhibiting its activity and preventing blood clot formation. The aptamer features a unique bimodular structure composed of a duplex module and a G-quadruplex motif, which together confer high affinity and specificity for thrombin. NU172 was the first aptamer anticoagulant to reach Phase II clinical trials, primarily developed for short-acting anticoagulation during medical procedures such as coronary artery bypass graft surgery and percutaneous interventions. Its mechanism allows for rapid onset and offset of action, making it suitable for settings where quick reversal of anticoagulation is desired[1][3][7]. The drug was initially developed by Archemix Corp., with subsequent development by Nuvelo and ARCA Biopharma[2][3][5].