Lanadelumab Reduces Pediatric HAE Attacks 95% in Real-World Analysis

Real-world data presented at the American College of Allergy, Asthma and Immunology (ACAAI) 2026 Annual Scientific Meeting show lanadelumab (Takhzyro) prophylaxis reduced attack frequency by 95% in pediatric patients with hereditary angioedema (HAE), according to a retrospective chart review.

Before the US Food and Drug Administration (FDA) expanded the lanadelumab label to children aged ≥ 2 years in February 2023, routine prophylaxis for children aged 6 to <12 years required dosing every 3 to 4 days, and no prophylactic option was approved for children aged 2 to 5 years.¹ The expanded approval was supported by safety, pharmacokinetic, and pharmacodynamic data from the phase 3 SPRING study, along with efficacy data extrapolated from the phase 3 HELP study.¹

“If a child had an attack, they’d have to go to the emergency room, get an IV started, get treated,” said William R. Lumry, MD, clinical professor of internal medicine at UT Southwestern Medical Center. “It was a big deal.”

Lanadelumab Effectiveness in Pediatric HAE: Real-World Attack Rates

The analysis drew on patient records from a 1-year baseline period before lanadelumab initiation, followed by a post-initiation period capturing attack frequency, severity, and resolution. Investigators also assessed health-related quality of life in treated patients. The cohort included 13 patients aged < 18 years.

Approximately 40% of patients were aged 6 to 12 years, and approximately 60% were aged 12 to 18 years. Most were male, most had type 1 HAE, and most were White. Patients initiated lanadelumab at varying points in their disease course, including after diagnosis, after a hospitalization, or after first symptom onset.

During the baseline period, patients experienced approximately 1 attack every 2 months. After lanadelumab initiation, attack frequency fell by 95%.

“So basically, [participants had] no attacks,” Lumry said. “Maybe 1 attack a year at [the] very most.”

Baseline attacks were frequently abdominal or peripheral, affecting the hands and feet. Some patients also reported facial, genital, and airway attacks.

Before treatment, most attacks required on-demand therapy, and few resolved without intervention. After lanadelumab initiation, 100% of patients reported attacks resolving without on-demand therapy.

Real-World Phase 3 SPRING Findings

The real-world findings align with results from the phase 3 SPRING study, an open-label, multicenter trial of lanadelumab in 21 patients aged 2 to <12 years.² In SPRING, the mean attack rate decreased by 94.8% from baseline (1.84 to 0.08 attacks per month), and 76.2% of patients were attack-free during the 52-week treatment period. No serious treatment-emergent adverse events or discontinuations due to such events occurred, and injection site pain was the most common treatment-emergent adverse event.

References

1. Lumry W, et al. Clinical Outcomes and Treatment Experiences Among Pediatric Hereditary Angioedema Patients Receiving Lanadelumab Prophylaxis. Presented at the American College of Allergy, Asthma and Immunology 2026 Annual Scientific Meeting; November 12-16, 2026; Phoenix, AZ.

2. US FDA approves Takeda’s Takhzyro (lanadelumab-flyo) to prevent hereditary angioedema (HAE) attacks in children 2 years of age and older. Takeda. Published February 3, 2023. Accessed November 12, 2026. https://www.takeda.com/newsroom/newsreleases/2023/us-fda-approves-takedas-takhzyro-lanadelumab-flyo-to-prevent-hereditary-angioedema-hae-attacks-in-children-2-years-of-age-and-older/

3. Maurer M, Lumry WR, Li HH, et al. Lanadelumab in patients 2 to less than 12 years old with hereditary angioedema: results from the phase 3 SPRING study. J Allergy Clin Immunol Pract. 2024;12(1):201-211.e6. doi:10.1016/j.jaip.2023.09.009