BioCryst Pharmaceuticals, Inc. announced the enrollment of the first patient in the pivotal APeX-P trial evaluating oral, once-daily ORLADEYO(R) (berotralstat) in pediatric hereditary angioedema (HAE) patients who are 2 to <12 years of age. ORLADEYO is the first and only oral therapy designed specifically to prevent HAE attacks in adult and pediatric patients 12 years and older. First approved by the U.S. Food and Drug Administration (FDA) in December 2020, ORLADEYO is available in many global markets.

APeX-P is an open-label trial designed to evaluate the pharmacokinetics (PK) and safety of ORLADEYO in pediatric HAE patients (2 to <12 years of age). The trial will consist of an initial 12-week standard-of-care (SOC) treatment period, followed by a subsequent open-label ORLADEYO treatment period lasting 48 weeks, with continuation up to 144 weeks. Patients will be enrolled into four dose cohorts, with body weight being used to determine assignment to each cohort.

Higher weight cohorts (Cohorts 1 and 2) will enroll first and in parallel, and safety assessments and PK modelling from all available PK data will then be used to confirm the weight bands for sequentially enrolling Cohorts 3 and 4. The effectiveness of ORLADEYO in APeX-P will be summarized using descriptive statistical methods. The primary endpoint of APeX-P is the characterization of the PK profile of ORLADEYO in patients aged 2 to <12 years. Following the completion of APeX-P, BioCryst plans to submit a supplemental New Drug Application (sNDA) for the potential expanded use of ORLADEYO for prophylaxis to prevent attacks in pediatric HAE patients.