The firm's researchers can produce billions of viruses, each with a different binding site from a human antibody.

ECONOMIST: Monoclonal antibodies

Biogen scientists crafted decoys by cloning and attaching the binding site of LFA-3 onto the Y-shaped tail of a harmless antibody.

FORBES: Skin Deep

Xolair is a monoclonal antibody to IgE that works like a Star Wars missile defense for allergies, binding to and inactivating excess IgE before it can trigger an attack.

FORBES: Magazine Article