Real-world treatment patterns and clinical burden of patients with hereditary angioedema treated with long-term prophylaxis

Abstract Background Long-term prophylaxis (LTP) may reduce the hereditary angioedema (HAE) burden by reducing attack frequency, but real-world evidence is limited. Objective To describe LTP treatment patterns and the frequency of HAE attacks leading to emergency department or inpatient visits (ED/IP) and healthcare resource use (HRU) before and after LTP initiation. Methods Patients initiating LTP in the Komodo Research Database (1/1/2021-1/30/2024) were followed until discontinuation or data end. Treatment adherence overall and among patients with > 30 days of treatment was measured as the proportion of days covered ≥ 80%. Treatment persistence, defined as no interruption ≥ 90 days or switch, was evaluated overall and among patients with > 30 days of treatment using Kaplan-Meier (KM) analysis with KM rates and corresponding 95% confidence intervals (CI). Rates of HAE attacks leading to ED/IP and per-patient-per-year all-cause HRU before and after LTP initiation were reported among patients with > 30 days of treatment. All analyses were descriptive and no statistical testing was conducted. Results Overall, 499 patients were included (57 Haegarda [11%], 257 Orladeyo [52%], 185 Takhzyro [37%]; mean follow-up = 11.3 months; median age = 39 years; 69% female), among whom 449 had > 30 days of treatment (mean follow-up = 12.5 months). At 12 months after LTP initiation, 52.6% of patients in the overall study sample and 57.0% of patients with > 30 days of treatment were adherent. Based on KM analysis, persistence rates at 12 months after LTP initiation were 58.7% (95% CI = 53.8%; 63.4%) in the overall sample and 65.1% (59.9%; 69.9%) among patients with > 30 days of treatment. Among the patients with > 30 days of treatment, 38% had ≥ 1 HAE attack leading to ED/IP in the year before LTP initiation (mean = 0.82 attacks), decreasing to 23% after (mean = 0.51 attacks). In these 449 patients, annual HRU remained substantial before and after LTP initiation across settings (IP = 2.4 and 1.7 days [0.3 and 0.2 admissions]; ED = 1.5 and 1.2 visits; outpatient = 21.0 and 19.3 visits, respectively). Conclusion Although recently available LTP can partly reduce the clinical burden of patients with HAE, novel therapies are needed to further alleviate this burden.