Berotralstat (BCX7353) is a novel oral prophylactic treatment for hereditary angioedema: Review of phase II and III studies

Background: Hereditary angioedema (HAE) is a rare genetic disorder characterized by unpredictable and potentially life-threatening episodes of swelling in various parts of the body. These attacks can be painful and debilitating, and affect a patient's quality of life. Every patient who experiences an attack should be treated with on-demand medication to mitigate attack severity and duration. Many patients with HAE also receive long-term prophylaxis to reduce the frequency and severity of edema episodes. Although long-term prophylaxis reduces the disease burden for patients with HAE, available intravenous and subcutaneous treatments are accompanied by a significant treatment burden because of the logistical, emotional, and physical challenges posed by their long-term parenteral nature. Androgens are an effective oral prophylactic treatment; however, they are associated with significant adverse events and are not suitable for all patients. Thus, the HAE community has expressed interest in the development of alternative oral prophylactic therapies for preventing HAE attacks. Objective: Here, we review the phase II and III clinical data of berotralstat (BCX7353), which was approved by the U.S. Food and Drug Administration in December 2020. Results: Berotralstat is an oral, second-generation, synthetic, small-molecule plasma kallikrein inhibitor taken once daily for the prevention of HAE attacks in patients ages 12 years. Results from the APeX studies (APeX-1 NCT02870972, APeX-2 NCT03485911, APeX-S NCT03472040, APex-) NCT03873116) demonstrated the efficacy of berotralstat as long-term prophylaxis for patients with HAE, which showed a reduction in the attack rate and on-demand medication usage. Berotralstat was well tolerated, and gastrointestinal treatment-emergent adverse events were generally mild and selflimited. Conclusion: Oral berotralstat is an effective and safe long-term prophylactic treatment for patients with HAE that will provide patients unable to tolerate parenteral therapies with the option of disease control. Berotralstat may be associated with reduced treatment burden compared with injectable therapies, highlighting the importance of patient preference with regard to the administration route of their HAE prophylactic treatment.