Home Therapy with Plasma-Derived C1 Inhibitor: A Strategy to Improve Clinical Outcomes and Costs in Hereditary Angioedema.

BACKGROUND Attacks of hereditary angioedema with C1 inhibitor deficiency (C1-INH-HAE) are commonly treated in the emergency department. Self-administration is emerging as an effective treatment option. In this study, we assessed the impact of home therapy with plasma-derived C1 esterase inhibitor (pdC1-INH) concentrate on treatment outcomes and costs. METHODS This is an observational study in C1-INH-HAE patients who switched to home therapy with pdC1-INH (Berinert®) after learning intravenous self-infusion in a training course at a center in Southern Italy. Before starting home therapy and after the first year of home therapy, patients were interviewed about their treatment and outcomes during the prior 12 months. Annual costs were analyzed by cost minimization from the Italian health care payer perspective and the societal perspective. Outcomes and costs before and after the switch to home therapy were compared. RESULTS The training course was attended by 36 participants, 17 (47.2%) of whom decided to switch to home therapy. This therapy was associated with a significant decrease in the mean annual number of hospitalizations (16.8 vs. 2.1, p = 0.003) and missed work/school days (20.3 vs. 7.1, p = 0.037) compared to conventional treatment. The times from symptom onset to treatment administration and from treatment administration to symptom improvement/resolution were not significantly different between the two strategies. The mean annual per-patient costs decreased with home therapy from EUR 30,010.57 to EUR 26,621.16 (11.3% saving) and from EUR 29,309.34 to EUR 26,522.04 (9.5% saving) from the societal and payer perspective, respectively. CONCLUSIONS Home therapy with pdC1-INH is a feasible strategy for the management of C1-INH-HAE and may result in cost savings.