Omeros Corporation (Nasdaq: OMER) today announced that it has obtained an exclusive license from The Regents of the University of California to a new series of antifibrinolytic agents. These optimized agents represent a significant potential advance in the control of surgical and traumatic bleeding.
"This is a good opportunity for Omeros and represents a potential life-saving treatment for patients. With the withdrawal of Trasylol® from the market in 2008, there is an immediate need for a safe and effective antifibrinolytic," stated Gregory A. Demopulos, M.D., chairman and chief executive officer of Omeros. "The ex vivo human and in vivo animal efficacy data look strong, and the regulatory pathway is well-defined. We have begun IND-enabling activities and are working to advance the program quickly to the clinic."
Excessive bleeding during cardiac surgery is known to increase overall morbidity and mortality. In an attempt to control this bleeding, patients undergoing cardiac and other extensive surgery often receive antifibrinolytic compounds. Until its permanent withdrawal from the market in 2008, the antifibrinolytic Trasylol® (aprotinin) had been shown in a number of studies to be more effective at reducing blood loss than the other two commonly used agents, tranexamic acid (TXA) and epsilon aminocaproic acid (EACA). Though effective, Trasylol® had a number of limitations. It was a bovine protein that was associated with anaphylactic reactions. Further, Trasylol® was non-selective and inhibited many proteins in addition to plasmin, including Factor XIa and kallikrein, important regulators of the coagulation cascade. Trasylol® was permanently withdrawn from the market after its use was found to be associated with increased mortality. While the specific cause of this increase remains unknown, an often-cited explanation is lack of specificity of Trasylol®.
TXA and EACA are lysine analogs that function as competitive inhibitors of plasminogen activation and, at much higher concentrations, noncompetitive inhibitors of plasmin. These agents are considered to be safer but less effective than Trasylol®. While TXA is approximately 10 times more potent than EACA, it is associated with a fourfold increase over EACA in the risk of seizures. Further, a study demonstrated that patients administered TXA required more transfusion product than patients who were administered Trasylol®, resulting in significantly higher overall transfusion-related costs for patients treated with the less expensive, generic agent TXA.