An International Delphi Study on Barriers to On-Demand Treatment of Hereditary Angioedema Attacks

Hereditary angioedema (HAE) is a rare inherited disorder characterized by unpredictable and potentially life-threatening attacks of swelling. This international Delphi panel aimed to address questions related to on-demand treatment of HAE attacks.

A modified Delphi method was conducted with three rounds of surveys. Two non-voting co-chairs designed and managed the surveys, data collection, and analysis with a third-party administrator. The international panel consisted of 19 expert HAE clinicians. Consensus was defined as ≥ 75% agreement with ≥ 75% of panelists voting.

The panel confirmed 24 statements across five key areas related to on-demand treatment: defining "early" treatment, barriers to early administration, burden of treatment, tolerability and convenience, and patient-clinician interactions. Panelists defined early treatment as ≤ 60 min after onset of an HAE attack. Obstacles to early treatment include recognition of an HAE attack, and embarrassment/anxiety about administering parenteral treatment. Access to on-demand treatment (i.e., carrying medication, cost, insurance coverage, regulatory approval) can be a burden for patients with HAE, and increasing access may improve adherence to guidelines. Logistical obstacles of parenteral administration that impact convenience, tolerability concerns (e.g., side effects), and cost of medication can all limit early use of on-demand treatment. Additional options for on-demand therapies beyond parenteral treatments could reduce some of the burdens. Panelists agreed that patient-physician shared decision-making should be utilized.

The Delphi consensus statements demonstrate the need for accessible and convenient on-demand treatments for HAE attacks that will enable patients with HAE to improve adherence to guidelines.