BACKGROUND:Hereditary angioedema (HAE) is a rare genetic disorder with symptoms often appearing during childhood. Current approved long-term prophylaxis (LTP) for children aged <12 years requires parenteral administration. Berotralstat is an oral, small-molecule plasma kallikrein inhibitor, approved as prophylaxis of HAE attacks in patients aged 12 years or older.
OBJECTIVE:To evaluate oral berotralstat for the LTP of HAE in pediatric patients through APeX-P (NCT05453968), the largest trial of LTP in patients with HAE aged 2 to <12 years.
METHODS:Before berotralstat initiation, patients received standard of care for 12 weeks. Pharmacokinetics, safety, and efficacy of berotralstat were assessed in a planned interim analysis.
RESULTS:Median (range) age of patients (N = 29) was 8.0 (3-11) years, with 48.3% female. Median age at symptom onset was 2.0 years, and 82.8% of patients reported symptom onset before 6 years. Steady-state berotralstat median (range) Tmax was 3.9 (0.9-6.0) hours, geometric mean (coefficient of variation) Cmax was 204 ng/mL (40%), and AUC0-last was 915 ng•h/mL (42%). Most common treatment-emergent adverse events (AEs) were nasopharyngitis, upper respiratory tract infection, and headache. There were no drug-related grade 3/4 or serious AEs, deaths, or discontinuations related to AEs. Median (range) HAE attack rate during standard of care was 0.96 (0-5.0) attacks per 4-week period. Median (range) HAE attack rates for each 4-week period from day 1 to week 48 were 0 (week 4: 0-4.0; week 48: 0-1.7).
CONCLUSION:Oral berotralstat was well tolerated and resulted in early and sustained reductions in HAE attack rates.
TRIAL REGISTRATION:ClinicalTrials.gov Identifier: NCT05453968 and ClinicalTrialsRegister.eu Identifier: EU CTN 2024-511257-22-00.