FDA Approves Ecallantide for Hereditary Angioedema

Yael Waknine

December 04, 2009

December 4, 2009 — The US Food and Drug Administration (FDA) has approved ecallantide subcutaneous injection (Kalbitor, Dyax Corp) for the treatment of sudden and potentially fatal fluid build-up associated with hereditary angioedema (HAE) in patients aged 16 years and older.

HAE, a genetic disorder caused by an inherited deficiency of plasma-derived C1-esterase inhibitor (C1-INH), is characterized by relapsing, self-limiting episodes of edema that occur primarily in subcutaneous tissue, the intestinal wall, and larynx.

C1-INH is a major endogenous inhibitor of plasma kallikrein, a proteolytic enzyme involved in the conversion of high-molecular-weight kininogen to the vasodilator bradykinin. Ecallantide exerts its effects by directly inhibiting kallikrein, thereby reducing excessive bradykinin production and symptoms of localized swelling, inflammation, and pain.

The product is the second to be approved by the FDA to treat HAE — a C1-INH concentrate for intravenous injection (Berinert, CSL Behring, Inc) was approved in October 2009 to treat acute abdominal attacks and facial swelling in HAE patients.

"Kalbitor offers another potentially life-saving option for those people with HAE," noted John Jenkins, MD, director, Office of New Drugs in the FDA's Center for Drug Evaluation and Research, in an agency news release. "FDA is committed to facilitating the development and approval of safe and effective therapies for patients with rare conditions."

Because anaphylaxis was reported in 3.9% of clinical trial patients, ecallantide should only be administered by a healthcare professional with appropriate medical support. Clinicians should be aware of similarities between symptoms of HAE and hypersensitivity reactions.

Other adverse events reported in 3% or more of study patients included headache, nausea, diarrhea, pyrexia, injection site reactions, and nasopharyngitis.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.