KING OF PRUSSIA, Pa., July 27, 2026
CSL has announced positive top-line Phase 3b clinical trial results supporting plans to seek an expanded pediatric indication for ANDEMBRY® (garadacimab-gxii) in children aged 2 to 11 years with Hereditary Angioedema (HAE). The investigational study demonstrated a favorable safety and tolerability profile consistent with previous clinical experience while showing that the majority of pediatric participants remained attack-free throughout the 12-month treatment period. ANDEMBRY is currently approved in more than 40 countries for the prevention of HAE attacks in adults and pediatric patients aged 12 years and older. Based on these encouraging findings, CSL plans to begin regulatory submissions for the expanded pediatric indication during the first half of the company’s fiscal year, with complete clinical data scheduled for presentation at an upcoming scientific congress. The latest results strengthen the growing clinical evidence supporting factor XIIa inhibition as an innovative long-term preventive strategy for patients living with this rare and potentially life-threatening genetic disorder.
Phase 3b Trial Demonstrates Strong Pediatric Safety and Efficacy
The multicenter, open-label Phase 3b study evaluated ANDEMBRY in 22 children between 2 and 11 years of age diagnosed with Hereditary Angioedema. Participants aged 6 to 11 years received 100 mg once monthly, while children aged 2 to 5 years were treated with 100 mg every two months. According to CSL, the therapy maintained a favorable safety profile, with results aligning closely with previous studies conducted in older patient populations. Importantly, the majority of enrolled children remained free from HAE attacks during the year-long treatment period, highlighting the medicine’s potential as an effective long-term prophylactic option for younger patients. The positive findings support CSL’s strategy to expand access to ANDEMBRY for pediatric patients who currently have limited preventive treatment options and reinforce confidence in the therapy’s clinical performance across multiple age groups.
ANDEMBRY Targets Factor XIIa to Prevent HAE Attacks
ANDEMBRY (garadacimab-gxii) is a fully human monoclonal antibody that selectively targets activated Factor XII (Factor XIIa), a plasma protein responsible for initiating the biological cascade that leads to Hereditary Angioedema attacks. By inhibiting Factor XIIa at the earliest stage of the inflammatory pathway, the therapy helps prevent the excessive production of bradykinin, the molecule responsible for causing severe episodes of swelling associated with HAE. This upstream mechanism differentiates ANDEMBRY from other available therapies that primarily target downstream components of the disease pathway. Because HAE attacks can affect the face, abdomen, extremities, and airway—and may become life-threatening if the throat is involved—effective long-term prevention remains a critical goal in disease management. The encouraging pediatric results further strengthen ANDEMBRY’s position as a novel prophylactic treatment designed to reduce attack frequency and improve quality of life for patients living with this rare genetic condition.
Advertisement
Regulatory Expansion Strengthens CSL’s Rare Disease Portfolio
The successful completion of the Phase 3b pediatric study represents another important milestone in CSL’s rare disease development strategy, supporting the company’s commitment to expanding innovative treatment options for underserved patient populations. The company plans to initiate regulatory filings seeking approval for use in children aged 2 to 11 years, potentially extending the benefits of ANDEMBRY to younger patients worldwide. Full clinical results will be presented at a forthcoming medical congress and submitted for publication in a peer-reviewed scientific journal, providing additional evidence for healthcare professionals and regulatory authorities. If approved, the expanded indication would further strengthen CSL’s leadership in hereditary angioedema treatment, reinforcing the company’s growing portfolio of innovative biologic therapies designed to improve long-term disease prevention and patient outcomes through advanced biotechnology.
Source: CSL press release
