Cold agglutinin disease is a rare, acquired chronic autoimmune hemolytic condition that leads to the destruction of red blood cells (hemolysis), chronic anemia, severe fatigue, and potentially fatal thrombotic events such as pulmonary embolism and stroke.
People living with cold agglutinin disease currently have no approved treatment options, and risk chronic iron overload from frequent blood transfusions to normalize hemoglobin levels. The disease occurs in approximately 16 people per million globally, including an estimated 5,000 people in the United States. Typically, symptom onset begins around age 60, and can be debilitating.
Cold agglutinin disease is caused by auto-immune mediated destruction of red blood cells. It is triggered by IgM auto-antibodies that bind to the surface of red blood cells and activate the classical complement pathway, leading to red blood cell destruction.
The classical complement pathway is a normal component of the innate immune system. However, when dysregulated, it is associated with multiple disease processes, including cold agglutinin disease. BIVV009 (formerly TNT009) is an investigational candidate that is designed to selectively inhibit the classical complement pathway. BIVV009 selectively targets C1s, the proximal initiator of the classical complement cascade, while leaving other complement cascade pathways intact.