ATLANTA, GA—Early self-treatment of hereditary angioedema (HAE) with icatibant was found to reduce time to symptom resolution and to decrease the duration of attacks compared late self-treatment, according to findings obtained from the international registry Icatibant Outcome Survey study (NCT01034969), presented at the 2017 AAAAI Annual Meeting.
“The findings from this preliminary analysis are hypothesis-generating and should be further evaluated to better understand the factors that drive early icatibant treatment,” cautioned lead study author Marcus Maurer, of the Department of Dermatology and Allergy, Charite-Universitatsmedizin Berlin, in Berlin, Germany. “Differences in local practice patterns, icatibant availability, and tendency of early treaters to treat any symptoms without delay may drive the prevalence of early use across countries,”
Hereditary angioedema (HAE) with C1 inhibitor (C1INH) deficiency is a rare and frequently painful genetic disorder. Icatibant is a subcutaneous, patient self-administered bradykinin BK2 receptor antagonist. The Icatibant Outcome Survey was a prospective international observational real-world drug safety and effectiveness registry study.
Self-treatment was considered early when the median time to administration of the first injection was <1 hour after attack onset. Self-treatment was considered late when the time-to-first injection median was ≥1 hour after symptoms onset.
A total of 229 patients from 10 countries were included in the study. Icatibant was used to treat 1,816 attacks. Early self-treatment was recorded for 89 (39%) patients and the late treatment group included 140 patients (61%). No significant age or gender differences were observed but early treatment rates varied between countries (for example, 77.1% in Germany/Austria vs. 11.6% in France).
Attacks involving a single anatomic location were reported in 93.6% of patients in the early treating group vs. 89.5% in the late treating group but this trend did not achieve statistical significance (P=0.08, n.s.).
HAE attack types varied between early- and late-treating patients. For example, skin attacks were more frequent in the early self-treating group compared to patients who treated late (50% vs. 35% respectively, P=0.0098). Abdominal attacks were treated more frequently in late-treaters versus those who treated early (67% vs. 49% respectively, P=0.0078). The researchers found no significant difference between the early- and late-self treatment groups in laryngeal attacks.
For patients who treated an HAE attack early, the median time to resolution was 3 hours (95% CI: 0.8, 9.3), compared to a median of 7 hours (95% CI: 3, 19.3; P<0.001) for those who treated late. Attack duration was 4 hours (95% CI: 1, 10.3) for patients who self-treated early vs. 12.5 hours (95% CI: 6.0, 26.0; P<0.001) in those patients who self-treated late.