Directed evolution of the first Kunitz domain of TFPI1 had already yielded the potent kallikrein inhibitor, Kalbitor® (ecallantide), which is an FDA-approved drug to treat acute attacks of hereditary angioedema.
Lanadelumab (DX-2930) is a new kallikrein inhibitor with the potential for prophylactic treatment of hereditary angioedema with C1 inhibitor deficiency.
In the past, few treatment options were available; however, several new therapies with proven efficacy have recently become available to treat and prevent HAE attacks, such as plasma-derived and recombinant C1-INHs that replace the deficient protein, bradykinin receptor antagonist (icatibant) that blocks bradykinin activity and kallikrein inhibitor (ecallantide) that prevents bradykinin release.