PROS1 and hyperinsulinemic hypoglycemia, familial, 4: In the last decade, many steps forward have been made in the search for new anticoagulant drugs capable of acting on the pro-coagulative activity of some pathological conditions such as atrial fibrillation or congenital anomalies of the blood coagulation system (factor V deficiency Leiden, protein C, and protein S deficiency, hyperhomocysteinemia) [1,2].