Characterization Of Hereditary Angioedema Attacks Requiring Reinjection Of Icatibant: Findings From The Icatibant Outcome Survey
Saturday, March 3, 2018
South Hall A2 (Convention Center)
Irmgard Andresen, MD, Hilary J. Longhurst, MD, Laurence Bouillet, MD PhD, Teresa Caballero, MD PhD, Andrea Zanichelli, MD, Marcus Maurer, MD, Anete S. Grumach, PhD, Anette Bygum, MD, Jaco Botha, Werner Aberer, MD
RATIONALE: Data from the Icatibant Outcome Survey (IOS; NCT01034969), an international registry monitoring the safety and effectiveness of icatibant for the acute treatment of C1-INH-HAE attacks, have shown that a minority of attacks (212/2672, 7.9%) required >1 dose of icatibant. To better understand reasons for icatibant reinjection we analyzed reinjection data from >4900 attacks collected in IOS.

METHODS: IOS patient/attack characteristics collected between July 2009-July 2017 were compared using descriptive statistics. Factors predictive of reinjection were determined using logistic regression.

RESULTS: Data from 4955 attacks in 526 patients (57.2% females) with C1-INH-HAE were analyzed. Approximately 90% of icatibant injections were self-administered. Most attacks (93.1%) were treated with a single icatibant injection. Of attacks that required icatibant reinjection, most (199/289 [68.9%]) were severe/very severe. Few laryngeal attacks (16/256 [6.3%]) required reinjection. Reinjection was significantly more likely for patients using long-term prophylaxis versus not (8.0% vs 6.3% respectively, P=0.023). Reinjection was significantly more likely for attacks of higher severity (odds ratio [95%CI] of 2.2 [1.6,3.1], P<0.0001) more likely, although not significantly, for patients based on lower BMI (<25kg/m2 vs ≥25kg/m2; 1.4 [0.9,2.3], P=0.1479). The second dose was administered >6 hours after the first dose in 163/195 (83.6%) attacks.

CONCLUSIONS: More than 90% of HAE attacks resolved with a single icatibant injection. The reinjection rate was higher for attacks with higher severity. Most patients reinjected >6 hours after the first dose, as recommended.