Which medication approved for treating acute attacks of Hereditary Angioedema (HAE) carries a significant black box warning for anaphylaxis?

Ecallantide, marketed as Kalbitor, is indeed associated with a significant black box warning for anaphylaxis, making it the correct choice for this question. Ecallantide is a recombinant protein that inhibits the activity of plasma kallikrein, which plays a crucial role in the pathophysiology of Hereditary Angioedema (HAE) by contributing to bradykinin release and subsequent angioedema attacks.

The black box warning highlights the potential risk of severe allergic reactions, including anaphylaxis, which practitioners must consider when prescribing this medication. As a result, healthcare providers are advised to monitor patients closely for any signs of an allergic reaction following administration.

In contrast, the other medications listed do not carry such a significant warning. Icatibant is an bradykinin receptor antagonist that is effective in treating acute HAE attacks but does not have a black box warning for anaphylaxis. Lanadelumab is a monoclonal antibody that acts as a preventive therapy for HAE, and while it can have side effects, anaphylaxis is not noted as a significant risk. Danazol, an androgen steroid, is used to prevent HAE attacks, but it is associated with a different safety