Icatibant for Multiple Hereditary Angioedema Attacks across the Controlled and Open-Label Extension Phases of FAST-3.

BACKGROUND

In randomized, controlled, double-blind, multicenter phase 3 studies, one icatibant injection was efficacious and generally well tolerated in patients with a single hereditary angioedema (HAE) attack. Here, the efficacy and safety of icatibant for multiple HAE attacks was evaluated across the controlled and open-label extension phases of the For Angioedema Subcutaneous Treatment (FAST)-3 study (NCT00912093).

METHODS

In the controlled phase, adults with HAE type I or II were randomized (1:1) to receive a single subcutaneous injection of icatibant 30 mg or placebo within 6 h of an attack becoming mild (laryngeal) or moderate (cutaneous/abdominal). Open-label icatibant was administered for severe laryngeal symptoms. In the open-label extension phase, patients could receive up to three icatibant injections per attack. Efficacy and safety were analyzed for the first five icatibant-treated attacks at any location (prospective analysis) and laryngeal attacks (post hoc analysis) across both phases. Efficacy outcomes were based on patient-reported symptom severity (visual analog scale).

RESULTS

In groups of patients with one to five icatibant-treated attacks at any location (n = 88), the median times to onset of symptom relief, onset of primary symptom relief and almost complete symptom relief were 1.9-2.1, 1.5-2.0 and 3.5-19.7 h, respectively. The same outcomes for laryngeal attacks (n = 25) were 1.0-2.0, 1.0-2.0 and 1.5-8.1 h, respectively. The most frequently reported adverse events were a worsening or recurrence of HAE attack, headache and nasopharyngitis. Two serious adverse events (arrhythmia and noncardiac chest pain) were considered to be related to icatibant.

CONCLUSIONS

Icatibant was efficacious and generally well tolerated across multiple HAE attacks, including laryngeal attacks.