From MedPage Today:
Some patients with hereditary angioedema (HAE) have suffered severe reactions to ecallantide (Kalbitor) in treating acute attacks, thus decreasing the hopes that the drug could be used at home.
New therapies for hereditary angioedema (HAE) (click to enlarge the image).
Unlike the other FDA-approved product for treating HAE attacks - a replacement protein that must be infused intravenously - ecallantide can be administered by subcutaneous injection. That had raised hopes that patients could keep syringes of the drug with them to use immediately in case of an attack.
But the anaphylactic reactions led the FDA to require a boxed warning on the product label, requiring that ecallantide be administered by a healthcare professional prepared to manage such reactions.
Another product, icatibant, is also making its way toward U.S. approval. That drug is a peptide-based selective bradykinin receptor antagonist -- like ecallantide, given by subcutaneous injection -- and is now available in Europe, but the FDA rejected an initial application in 2008.
Updated, 2011: Icatibant is approved for home use. Ecallantide must be administered in a physician-monitored environment.
AAAAI: Study Continues of HAE Drug Reactions. MedPage Today.
Virtually No Relapses After Ecallantide for Acute HAE attacks, despite short half-life. Medscape, 2011.