Phase III APeX-2 and APeX-S trials of BCX 7353 show improvements in hereditary angioedema.- BioCryst Pharma

BioCryst Pharmaceuticals announced new data from the phase III APeX-2 and APeX-S clinical trials, which showed that hereditary angioedema (HAE) patients taking oral, once-daily BCX 7353 (berotralstat) experienced sustained decreases in their attack frequency and improvements in quality of life (QoL) scores over 48 weeks. Berotralstat was also safe and generally well-tolerated over 48 weeks in both APeX-2 and APeX-S.

In APeX-2, 31 patients who were randomized to 150 mg of oral, once-daily berotralstat at the beginning of the study and completed 48 weeks of therapy had a mean baseline attack rate of 2.9 attacks per month, which declined to 1.5 attacks per month after one month and to 1.0 attack per month at 12 months.

In APeX-S, patients completing 48 weeks of treatment on 150 mg of berotralstat (n=73) had a median attack rate of zero attacks per month in six of the 12 months, including month 12 (week 48). The low attack rate experienced by HAE patients on 150 mg of oral, once-daily berotralstat reduced the burden of disease and translated into clinically meaningful improvements in mean angioedema quality of life (AE-QoL) total score, as measured by the disease-specific AE-QoL questionnaire. This persisted through month 12 (week 48) in the APeX-S trial. Improvements in mean change from baseline AE-QoL total score exceeding the minimum clinically important difference (MCID) of six points were observed by week four and at week 48 the mean AE-QoL total score for the berotralstat 150-mg treatment group had decreased by 14.7 points compared with baseline.

An integrated 48-week analysis across both APeX-2 and APeX-S showed no new safety findings. Berotralstat was safe and generally well tolerated in a total of 342 patients with a total of 232 patient-years of daily oral dosing. The most common adverse event was the common cold, which occurred with similar frequency in berotralstat and placebo patients. Gastrointestinal events led to discontinuation of berotralstat in 3.2 percent of patients. Drug-related serious adverse events occurred in three of 342 subjects (0.9 percent) and resolved after stopping or interrupting berotralstat dosing. The data were presented at the European Academy of Allergy and Clinical Immunology (EAACI) Digital Congress.