Presentation (CTI)

OBJECTIVES: Hereditary angioedema (HAE) is a rare, chronic, disease causing recurrent, unpredictable, and potentially life-threatening swelling episodes that most commonly affect the extremities, face, abdomen, genitals and larynx. While incurable, existing treatments include long- and short-term management, and on-demand options for attacks. This study used data from the Swedish National Prescribed Drug Register (NPR), to examine the prevalence, incidence, and treatment patterns of HAE in Sweden since the introduction of new long-term prophylactic (LTP) treatments in late 2021. In line with Swedish treatment guidelines, patients with HAE, including those on LTP, are advised to keep two doses of on-demand medication readily accessible for managing acute attacks.
METHODS: Data for patients with at least one dispensed HAE treatment between January 2020 and December 2024 was extracted from the NPR. The individual patient-level data was analysed to identify starting, continuous and concomitant use of HAE treatments.
RESULTS: The total number of patients treated for HAE has increased from 188 to 245 patients between 2021 and 2024. This corresponds to a prevalence and incidence rate of 2.31/100,000 and 0.36/100,000 in 2024, respectively. Of treatments with reimbursement for LTP, lanadelumab was the most frequently used. Icatibant was the most dispensed concomitant treatment to LTP, followed by pdC1-INH. After initiating LTP treatment, ~40% of patients were dispensed concomitant use of on-demand/short-term treatment at least at three separate occasions, while ~20% were dispensed at five or more occasions annually.
CONCLUSIONS: The observed prevalence aligns with prior estimates, though the incidence, when measured as number of new patients treated for HAE, is higher than what has been observed elsewhere. Despite restrictive reimbursement criteria, lanadelumab is the most prescribed LTP. The dispensing of on-demand/short-term treatment at least three times annually, indicates that a large share of patients potentially are not attack-free despite treatment with LTP.