METHODS: In the COMPACT study, patients self-administered C1-INH (SC) or placebo twice weekly in a double-blind, crossover manner over two 16-week treatment periods. Blood samples were drawn for assessment of C1-INH functional activity at screening; at weeks 1, 3, 5, 8, 11, and 14 of each treatment period; and at the end-of-study visit. Observed C1-INH functional activity was stratified by age group (≤17 years and >17 years) and plotted against time. In addition, PK parameters derived from a population PK analysis of the COMPACT study were evaluated.
RESULTS: Similar C1-INH functional activity over time was observed in patients ≤17 years and >17 years. Mean C1-INH functional activity after administration of C1-INH (SC) 60 IU/kg ranged from 52.9% to 64.9% in adolescents and from 63.9% to 69.4% in adults, well above the critical threshold of 40%. Population PK analysis in subjects with HAE showed that within the age range analyzed (12-72 years), age did not have a clinically relevant effect on the PK of C1-INH functional activity after SC administration.
CONCLUSIONS: Overall, these analyses demonstrate similar PK of C1-INH functional activity after administration of C1-INH (SC) in adolescents and adults.