OBJECTIVES: Available literature suggests that parenteral HAE treatments are burdensome to patients. As the HAE therapeutic landscape evolves, gaining a better understanding of the patient-reported clinical, economic, and humanistic burden of parenteral HAE therapies is critical to addressing unmet treatment needs.

METHODS: We conducted a targeted literature review (TLR) to assess the burden of parenteral HAE therapies on individuals with HAE. Searches were conducted in PubMed and Google Scholar. We prioritized peer-reviewed articles and conference proceedings published in English from January 1, 2017-November 1, 2022 for inclusion. We considered older articles, if relevant.

RESULTS: We identified nine publications. Most studies were observational (78%) and conducted in the United States (67%). Studies reviewed only reported outcomes among adult patients. Adverse events were a concern, with one study reporting 98% of patients using icatibant had injection site reactions. In another study, patients taking on-demand therapy reported refusing self-administration due to fear of injection (69%), lack of skills (47%), interference in daily activities (44%), and financial constraints (33%).

Significant humanistic and clinical burden was also reported across parenteral HAE therapies. One study found 19% of patients skipped their prophylaxis medication because injections or infusions were inconvenient. Another study found that the majority of patients (62%) who used a peripheral vein to administer treatment reported difficulty finding a usable vein, and more than half of intravenous prophylaxis users (51%) were dissatisfied with the length of time required to prepare and administer their medication.

CONCLUSIONS: Parenteral HAE therapies are burdensome for patients, yielding significant clinical, economic, and humanistic impacts. Novel, easy to administer HAE treatments, especially in the on-demand space—where only parenteral therapies exist—may address unmet patient needs and improve treatment outcomes. Future research should examine injection burden among patient subpopulations (e.g., pediatrics/adolescents) to ensure therapeutic interventions are appropriately tailored.