Dyax Corp was incorporated in the state of Delaware in the year 1989, and merged with Protein Engineering Corporation in 1995. It is a biopharmaceutical company focused on Hereditary Angioedema and Other Plasma-Kallikrein-Mediated Disorders and Licensing and Funded Research Portfolio. The Company develops and commercializes treatments for hereditary angioedema and to identify other disorders that are mediated by plasma kallikrein. It is engaged in identifying and developing treatments for patients who experience PKM angioedema. Plasma kallikrein, an enzyme found in blood, produces bradykinin, a protein that causes blood vessels to enlarge or dilate, which can cause swelling known as angioedema. Excess plasma kallikrein activity plays a role in HAE and could potentially play a role in a number of inflammatory diseases, including Crohn's disease, psoriasis, rheumatoid arthritis, and various mast cell disorders. It also develops KALBITOR for the treatment of acute attacks of HAE. KALBITOR is currently distributed through a limited network of wholesale, hospital and specialty pharmacy arrangements. Its portfolio of product candidates being developed by licensees using its phage display technology. For KALBITOR as a treatment for HAE, its competitors include: Manufacturers of corticosteroids. Other competitors for the treatment of HAE are companies that are developing small molecule plasma kallikrein inhibitors. The preclinical study and clinical testing, manufacture, labeling, storage, record keeping, advertising, promotion, export, and marketing, among other things, of its products and product candidates, including KALBITOR and those of its licensees, are subject to extensive regulation by governmental authorities in the United States and other countries.