D3.491 - Satisfaction with Sebetralstat as On-Demand Treatment of Hereditary Angioedema Attacks in KONFIDENT-S

Sebetralstat, an oral, on-demand plasma kallikrein inhibitor, was recently approved for the treatment of HAE attacks in patients aged ≥12 years. We present interim treatment satisfaction data from participants who treated attacks with sebetralstat in the KONFIDENT-S (NCT05505916) study.

KONFIDENT-S is an ongoing 2-year open-label extension study. Treatment satisfaction was assessed 24h after treatment for each attack on a 7-point scale from extremely dissatisfied (-3) to extremely satisfied (3).

As of September 30, 2025, 115 participants provided satisfaction data (median age, 36.0 years; 67.8% female) for 1593 attacks treated with sebetralstat 600 mg (41.5% mild; 42.8% moderate; 15.6% severe/very severe). Primary attack locations included 42.1% mucosal (including 28 laryngeal) and 57.9% subcutaneous. Median time to treatment was 20.0 minutes (IQR, 1.0-77.0). Most participants (66.3%) treated attacks within <1 hour of onset. Within 12 hours, a second dose of sebetralstat was administered for 22.0% of attacks and injectable conventional treatment was used for 5.0% of attacks. The median satisfaction score for all attacks was 2 (very satisfied). For 91.1% of attacks (27.2% extremely satisfied, 38.4% very satisfied, 19.1% satisfied, 6.3 % neutral) no dissatisfaction was reported. A trend was observed between shorter time to treatment and better treatment satisfaction (Pearson correlation, |r|=0.084; p-value 0.0008); no correlation was observed between baseline severity and treatment satisfaction.

In this interim analysis of KONFIDENT-S, the majority of participants (87.5%) reported being satisfied when using oral sebetralstat as an on-demand treatment of attacks, with no dissatisfaction reported for the vast majority (91.1%) attacks.