Management of patients with hereditary angioedema in Germany: comparison with other countries in the Icatibant Outcome Survey

Abstract

Background: The Icatibant Outcome Survey (IOS; NCT01034969) is a Shire-sponsored, international, observational study monitoring the safety and effectiveness of icatibant, a bradykinin B2 receptor antagonist approved for the acute treatment of adults with hereditary angioedema with C1 inhibitor deficiency (HAE-C1-INH).

Objective: To report IOS data comparing demographic and icatibant treatment outcomes in patients with HAE-C1-INH from Germany to HAE-C1-INH patients from 11 other IOS countries.

Methods: A descriptive, retrospective, comparative analysis of data from 685 IOS patients with HAE-C1-INH from seven centres in Germany (n = 93) vs. centres from Austria, Brazil, Czech Republic, Denmark, France, Greece, Israel, Italy, Spain, Sweden and the United Kingdom (n = 592, July 2009-January 2017). Icatibant treatment outcomes were retrieved from patients with complete attack outcome data for time to treatment, time to resolution and attack duration (160 attacks in 42 German patients and 1442 attacks in 251 patients from other IOS countries).

Results: German patients reported significantly fewer severe/very severe attacks (38.7% vs. 57.5%, respectively; P < 0.001). The proportion of attacks treated with a single icatibant injection was significantly higher in German patients (97.1% vs. 91.6%, P = 0.0003). The median time to treatment (0.0 h vs. 1.5 h), time to resolution (3.0 h vs. 7.0 h) and attack duration (4.3 h vs. 10.5 h) in German patients vs. other IOS countries were all significantly shorter (all P < 0.0001). No meaningful differences were identified between patients from Germany and other countries with regard to sex, median age at enrolment, median age at symptom onset and median age at diagnosis.

Conclusion: German IOS patients share similar demographic characteristics to patients from other IOS countries yet treat their attacks with icatibant significantly earlier and have markedly fewer severe or very severe attacks. Factors including regional access to and availability of icatibant may drive these outcomes and warrant further investigation.

Figure 1

Attack severity. *All calculations exclude the ‘Unknown’ category. ^†Other countries include patients from Austria, Brazil, Czech Republic, Denmark, France, Greece, Israel, Italy, Spain, Sweden and the United Kingdom. Comparison based on generalized linear model for repeated measures comparing ‘(very mild + mild + moderate)’ vs. ‘(severe + very severe)’.

Figure 2

Attack duration. *Other countries include Austria, Brazil, Czech Republic, Denmark, France, Greece, Israel, Italy, Spain, Sweden and the United Kingdom.

Figure 3

Time to treatment vs. attack duration for German vs. other IOS patients. *Other countries include Austria, Brazil, Czech Republic, Denmark, France, Greece, Israel, Italy, Spain, Sweden, and the United Kingdom. IOS, Icatibant Outcome Survey.

Figure 4

Ongoing long‐term* or short‐term* prophylaxis for patients with available prophylaxis data. *At IOS entry and/or during the follow‐up period. **Zero count. ^†Other countries include patients from Austria, Brazil, Denmark, France, Greece, Israel, Italy, Spain, Sweden and the United Kingdom.