Effects of TNX-832 (Sunol cH36) in Subjects With Acute Lung Injury/Acute Respiratory Distress Syndrome

Tissue factor (TF) is a transmembrane glycoprotein that acts as the principal initiator of the extrinsic coagulation pathway. TF is a key mediator between the immune system and coagulation and is the principal activator of coagulation. The TF-FVIIa complex activates FX and FIX, resulting in the cleavage of prothrombin to thrombin. Normally, localized activation of the coagulation cascade associated with inflammatory responses plays a role in controlling the spread of infectious agents; however, aberrant TF expression often leads to serious thrombotic disorders. TF-dependent thrombosis has been associated with many diseases including septic shock, coronary artery disease (CAD), cancer, and many inflammatory and autoimmune disorders such as lupus, rheumatoid arthritis, psoriasis, and inflammatory bowel disease. Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are forms of acute respiratory failure characterized by diffuse pulmonary infiltrates, pulmonary hypertension, refractory hypoxemia, loss of pulmonary compliance and normal hydrostatic pressures. ALI and ARDS commonly occur in patients with acute catastrophic events such as sepsis, trauma and severe pulmonary infections. The incidence of ALI and ARDS is extremely high in patients with sepsis. By blocking the initiating events of extrinsic coagulation activation, their effects on pro-inflammatory events in the lungs and disordered fibrin deposition may be corrected and the evolution of severe structural and functional injury may be averted during ALI/ARDS. TNX-832 (formerly known as Sunol-cH36), directed against human TF, which can block the pathological complications of TF-dependent thrombus formation. The blockage by TNX-832 of initiating events in the extrinsic coagulation pathway may attenuate the effects on pro-inflammatory events in ALI/ARDS patients, thereby averting or decreasing disordered fibrin deposition and averting the evolution of severe structural and functional injury.