Kalbitor (Ecallantide)

Kalbitor (ecallantide) is a medication used to treat hereditary angioedema (HAE) attacks. It is approved by the U.S. Food and Drug Administration (FDA) for use in HAE patients, ages 12 and older. It is manufactured by Shire, a biopharmaceutical company that specializes in rare diseases.

How Kalbitor works

Angioedema is a swelling underneath the skin caused by insufficient amounts of functional C1 inhibitor protein. This protein inhibits the actions of another protein called kallikrein, a member of the complex network of blood proteins that direct the inflammatory swelling process in the body. If kallikrein is not deactivated by C1 inhibitor protein, it triggers the release of another protein called bradykinin. Bradykinin causes blood vessels to dilate and become more permeable, allowing fluid to leak out and accumulate in tissues and cause swelling.

Kalbitor inhibits the activity of kallikrein, reducing the release of bradykinin and swelling during an angioedema attack. It is administered as an injection beneath the skin.

Kalbitor in clinical trials

Kalbitor’s FDA approval was based on results from a number of clinical trials (NCT00456508, NCT00457015, NCT00262080, NCT01826916, NCT01059526) that demonstrated its safety and effectiveness.

There is currently a small Phase 2 clinical trial (NCT01832896) evaluating its safety and tolerability in children with hereditary angioedema, ages 2 to 16. The trial is recruiting participants in New York, who are treated with ecallantide for angioedema attacks. The amount of time until symptom relief is measured, as well as incidence of adverse events.

Further details

Because some people have severe allergic reactions to Kalbitor, the medication should only be injected by a medical professional in a healthcare setting where patients can be monitored. Most allergic reactions occur within an hour after injection.


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