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Alexion.US

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The Complement System

What is the Complement System?

What is the Complement System?

The complement system is part of the immune system and essential to the body’s defense against infection. When this system is thrown out of balance, or disregulated, it can be a key driver of many devastating diseases. We are exploring multiple targets in the complement cascade to accelerate the discovery of new life-changing therapies.

Beyond Complement

Learn how we're advancing research to help address rare diseases with high unmet needs to help make a difference for patients and their families.