Hereditary angioedema (HAE) resulting from the deficiency of the
C1 inhibitor protein is a
rare disease, characterized by paroxysms of
edema formation in the subcutis and in the submucosa.
Edema can cause obstruction of the upper airway, which may lead to
suffocation. Prompt elimination of
edema is necessary to save patients from this life-threatening condition. Essentially, these edematous attacks are related to the activation of the
kinin-
kallikrein system and the consequent release of
bradykinin.
Ecallantide (known as
DX-88 previously), a potent and specific inhibitor of
plasma kallikrein is an innovative medicinal product. This is the only agent approved recently by the FDA for all localizations of edematous HAE attacks. Its advantages include no risk of viral contamination, high selectivity, very rapid onset of action, good tolerability, and straightforward subcutaneous administration. Owing to the risk of
anaphylaxis,
ecallantide should be administered by a health care professional. A postmarketing survey to improve risk-assessment and risk-minimization has been launched. The results of these studies may lead to the approval of
ecallantide for
self-administration.