Andembry (Garadacimab-gxii): A Novel Monoclonal Antibody for Preventing Hereditary Angioedema Attacks

Abstract

Hereditary angioedema (HAE) is a rare autosomal dominant disorder characterized by recurrent, potentially life-threatening episodes of angioedema affecting the skin, gastrointestinal tract, and airway. It results from dysregulation of the kallikrein–kinin system due to C1-esterase inhibitor deficiency or dysfunction, leading to excessive bradykinin production and increased vascular permeability. Despite advances in prophylactic therapies such as C1-INH replacement, kallikrein inhibitors, and bradykinin receptor antagonists, limitations including frequent dosing, breakthrough attacks, and variable response, remain. Garadacimab is a novel fully human monoclonal antibody that targets activated factor XII (FXIIa), inhibiting initiation of the contact activation pathway upstream of bradykinin generation. Blocking FXIIa, it prevents prekallikrein activation and downstream inflammatory cascade amplification. Clinical trials across Phase 1–3 studies demonstrate consistent pharmacodynamic target engagement, dose-dependent suppression of the kallikrein pathway, and significant reductions in attack rates, with a substantial proportion of patients remaining attack-free. The pivotal Phase 3 (VANGUARD) study further confirmed sustained efficacy and meaningful improvements in health-related quality of life. Garadacimab has shown a favorable safety profile, with mostly mild to moderate adverse events and no major safety concerns. Its long half-life enables once-monthly subcutaneous administration, potentially improving adherence and reducing treatment burden compared with existing therapies. Overall, FXIIa inhibition with Garadacimab represents a promising upstream prophylactic strategy for HAE, addressing key limitations of current treatments and offering durable disease control. Further real-world and comparative studies are needed to define its long-term role in clinical practice and broader applicability in contact system–mediated disorders.