Alexion Pharmaceuticals, Inc. (API) is engaged in the discovery and development of therapeutic products to treat patients with a wide array of severe disease states, including hematologic, cardiovascular and autoimmune disorders. Since inception, the Company has devoted substantially all of its resources to drug discovery, research and product and clinical development. The Company's significant expertise in the discovery and development of antibody therapeutics, as well as in understanding and inhibiting the aberrant manifestation of a component of the human immune system known as complement. Anti-bodies are proteins that bind specifically to selected targets or antigens in the body. After the anti-body binds to its target it may activate the body's immune system against the target, block activities of the target or stimulate activities of the target.