Complement Inhibition

Soliris® (eculizumab) works by inhibiting the complement protein C5, which acts at a relatively late stage in the complement cascade. The groundbreaking complement inhibition technology of Soliris has the potential to transform the lives of patients with a variety of complement-mediated diseases, including those that involve uncontrolled complement activation occurring either through excessive complement activation, or in patients who lack naturally occurring complement regulatory proteins.

When enzymatically activated, specific fragments of the complement protein C5 are directly involved in activating host cells, attracting immune cells that can cause inflammation, and destroying cells by triggering pore formation on the cell membrane. By blocking the complement cascade at C5 and thereby preventing C5 activation, the normal disease-preventing functions of complement remain largely intact, while C5 activation that leads to inflammation and cell destruction is impeded.

Another potential therapeutic target within the complement system is activated fragments of complement protein C3. When the complement system is activated, a fragment of C3 known as C3d is generated and attaches itself to injured cells and tissues. By specifically targeting these areas of inflammation through specific C3d binding, it is thought that disease-causing complement activation can be blocked and inflammation can be controlled directly at the site at which it is occurring.

Through research and development efforts across the complement platform, Alexion strives to enhance the world’s understanding of the complement system and unlock its vast potential in treating some of the most life-threatening and debilitating diseases.