Long‐term safety and effectiveness of berotralstat for hereditary angioedema: The open‐label APeX‐S study

Background Berotralstat (BCX7353) is an oral, once-daily inhibitor of plasma kallikrein recently approved for prevention angioedema attacks in adults and adolescents with hereditary (HAE). The objective this report to summarize results from interim analysis ongoing long-term safety study berotralstat patients HAE. Methods APeX-S ongoing, phase 2, open-label conducted 22 countries (ClinicalTrials.gov, NCT03472040). Eligible a clinical diagnosis HAE due C1 deficiency (HAE-C1-INH) were centrally allocated receive 150 or 110 mg once daily. primary was determine the secondary evaluate effectiveness. Results Enrolled (N = 227) received (n 127) 100) median (range) duration exposure 342 (11–540) 307 (14–429) days 150-mg 110-mg groups, respectively. Treatment-emergent adverse events (TEAEs) occurred 91% 206) patients. most common TEAEs across treatment groups upper respiratory tract infection 91, 40%), abdominal pain 57, 25%), headache 40, 18%), diarrhea 31, 14%) mostly mild moderate. Fifty percent 113) had at least one drug-related event (AE; mg, n 57 [45%]; 56 [56%]), discontinuations AEs 19 (8%) (150 13 [10%]; 6 [6%]). Three (1.3%) experienced serious TEAE. Among who through 48 weeks 73; 30), attack rates low month 1 1.0 attacks/month; 0.5 attacks/month) remained 12 months (0 attacks/month both dose groups). Mean followed similar trend, no evidence patient tolerance emerged. In quality life scores showed clinically meaningful changes baseline. Conclusions analysis, doses, daily, generally well tolerated. Effectiveness support durability robustness as prophylactic therapy Trial registration registered ClinicalTrials.gov (NCT03472040).