This is a fully human IgG1 monoclonal antibody using the same sequences as the therapeutic antibody lanadelumab. It specifically targets plasma kallikrein (pKal) and is indicated for prophylactic treatment to prevent attacks of hereditary angioedema (HEA). Kallikrein is a protease responsible for cleaving high molecular weight kininogen to generate the pro-inflammatory peptide bradykinin, a potent vasodilator. HEA is an autosomal dominant disorder caused by the presence of C1 deficiency. Because the activity of plasma kallikrein is regulated by C1 esterase inhibitor, patients deficient in C1 esterase inhibitor may face an increased risk of excessive production of bradykinin leading to severe angioedema. Lanadelumab effectively blocks the proteolytic active site of plasma kallikrein, thereby preventing kininogen cleavage and subsequent bradykinin release. It is a selective inhibitor and does not bind to prekallikrein or interfering with other serine proteases.