Three-year real-world outcomes of lanadelumab prophylaxis in hereditary angioedema: Complete disease suppression and psychosocial benefits in two East Asian patients.

Hereditary angioedema (HAE) is a rare, potentially life-threatening disorder characterized by recurrent, disabling episodes of subcutaneous or submucosal swelling. Lanadelumab, a monoclonal antibody targeting plasma kallikrein, is approved for long-term prophylaxis and has shown high efficacy in clinical trials. However, real-world data on its prolonged use, particularly from East Asia, remain scarce. This report evaluates 3-year clinical and patient-reported outcomes of lanadelumab prophylaxis in two Japanese patients with HAE type I. Both male patients (in their 30s and 70s) received subcutaneous lanadelumab, 300 mg, every 2 weeks, later extended to every 4 weeks following disease stabilization. Clinical efficacy was assessed by attack frequency. Patient-reported outcomes (PROs) included the Angioedema Control Test (AECT), Angioedema Quality of Life Questionnaire (AE-QoL), Hospital Anxiety and Depression Scale (HADS), and Treatment Satisfaction Questionnaire for Medication (TSQM-9). Safety and tolerability were also monitored. Both patients achieved complete or near-complete elimination of HAE attacks during the 156- week follow-up. AECT scores reached the maximum of 16 by week 12 and remained stable. AE-QoL scores improved by approximately 30 points, reflecting sustained quality-of-life benefits. HADS-Anxiety scores declined into the normal range, indicating reduced anticipatory anxiety. TSQM-9 global satisfaction remained above 90 out of 100, and no serious adverse events occurred; one patient experienced mild transient injection-site swelling. This case series presents the longest real-world follow-up of lanadelumab in East Asia. Findings confirm its sustained efficacy, safety, and psychosocial benefits, including enhanced quality of life and emotional recovery. These findings suggest that lanadelumab may play an important role in the long-term management of HAE in Asian clinical settings.