Real-world outcomes in hereditary angioedema: first experience from the Icatibant Outcome Survey in the United Kingdom

Hilary J. Longhurst, John Dempster, Lorena Lorenzo, Matthew Buckland, Sofia Grigoriadou, Christine Symons, Claire Bethune, Vincent Fabien, Catherine Bangs, Tomaz Garcez

Hereditary angioedema (HAE) is a potentially life-threatening, bradykinin-mediated disease, often misdiagnosed and under-treated, with long diagnostic delays. There are limited real-world data on best-practice management of HAE in the UK. To characterize the clinical profile, management and outcomes of patients with HAE type I and II from three specialist centres in the UK using data from the Icatibant Outcome Survey (IOS; Shire, Zug, Switzerland), an international observational study monitoring safety and effectiveness of icatibant, a selective bradykinin B2 receptor antagonist. We performed retrospective analyses of IOS data for patients with HAE type I and II from three centres in the UK and compared UK data with pooled IOS data from 10 countries (48 centres). Analyses included 73 UK and 579 non-UK patients with HAE type I or II. Median diagnostic delay was 6.2 and 5.9 years, respectively. Analysis of data collected from February 2008 to July 2016 included 286 icatibant-treated attacks in 58 UK patients and 2553 icatibant-treated attacks in 436 non-UK patients (median of 3.0 attacks per patient in both groups). More attacks were treated by icatibant self-administration in UK patients (95.8%) than in non-UK patients (86.8%, p < 0.001). Time to icatibant treatment, time to resolution and attack duration were not significantly different in the UK versus non-UK patients. UK patients from the specialist centres studied report similar diagnostic delay and similar icatibant treatment outcomes to their non-UK counterparts. However, improvements in the timely diagnosis of HAE are still required.Trial registration ClinicalTrials.gov NCT01034969.