Treatment of Hereditary Angioedema With Plasma-Derived C1 Inhibitor: A Review.

Hereditary angioedema (HAE) is clinically characterized by recurrent episodes of localized edema. HAE typically occurs due to a deficiency of functional C1 inhibitor (C1INH, HAE-C1INH); in addition, several types of HAE with normal quantity and activity of C1INH (HAE-nC1INH) have recently been classified, which occur due to different gene mutations. C1INH plays an integral role in the kallikrein-kinin system, where a deficiency of functional C1INH results in overproduction of bradykinin leading to subcutaneous and submucosal edema. Plasma-derived C1INH (pdC1INH) replacement therapy for hereditary angioedema has been in use clinically for over 40 years and has been developed for both intravenous and subcutaneous administrations. In this review, we provide an in-depth overview of the efficacy and safety of pdC1INH in clinical trials and real-world studies, and guideline recommendations for pdC1INH replacement therapy as a first-line treatment for on-demand therapy, short-term prophylaxis, and long-term prophylaxis in patients with HAE-C1INH Type 1 and 2, including special patient populations.