Association Between the Angioedema Control Test and Attack Frequency in Hereditary Angioedema.

BACKGROUND: Hereditary angioedema (HAE), defined by unpredictable, painful, acute swelling attacks affecting several bodily locations, diminishes patients' quality of life. Assessing disease activity, burden, and treatment response pose challenges in routine care. The patient-reported Angioedema Control Test (AECT) is a subjective measure of HAE disease control. Criterion validity of AECT with objective measures of disease control has not been previously assessed. This study evaluates the criterion validity of AECT using investigator-confirmed HAE attack rate in patients with HAE. METHODS: The Phase 3 OASIS-HAE study (NCT05139810) randomized patients with HAE to receive donidalorsen 80 mg or placebo subcutaneously for 24 weeks. The full analysis population included all dosed patients (N = 90), pooled across treatment arms. This post-hoc analysis examined the correlation between AECT and HAE attacks at Baseline, 12, and 24 weeks. RESULTS: AECT scores correlated moderately to strongly with HAE attack rate (ρ = -0.40 to -0.85). Mean attack rates differed significantly between poor (AECT < 10) and well-controlled (AECT ≥ 10) disease subgroups at study visits. At Week 24, 97.4% of patients reporting complete disease control (AECT maximum score of 16) had an attack rate of 0; the remaining patient had 1 attack. Patients with no attacks had a mean AECT score of 15.1 versus 7.7 for patients with attack rates > 0. CONCLUSION: This study supports the criterion validity of AECT in patients with HAE scores. AECT scores were strongly associated with objective disease control. AECT may be a valuable tool for monitoring disease control in patients with HAE.