CRISPR-Cas9 gene editing for hereditary angioedema: current treatments and emerging therapies

Hereditary angioedema (HAE) is a rare autosomal dominant disorder marked by episodic, non-urticarial swelling due to C1 esterase inhibitor (C1-INH) deficiency or dysfunction, leading to excessive bradykinin-mediated vascular permeability. While current treatments focus on symptomatic control using C1-INH replacement or kallikrein inhibitors, they require frequent administration and do not address the underlying genetic defect. CRISPR-Cas9 gene-editing technologies, particularly the investigational therapy NTLA-2002, offer a transformative approach by targeting the KLKB1 gene to durably reduce plasma kallikrein levels. This narrative review summarizes the pathophysiology and conventional treatments of HAE, and highlights emerging clinical evidence supporting the safety and efficacy of NTLA-2002. Preliminary trials demonstrate substantial reductions in HAE attack frequency and plasma kallikrein, with minimal adverse events. However, concerns about long-term safety, off-target effects, ethical implications, and accessibility remain. CRISPR-based therapeutics such as NTLA-2002 represent a paradigm shift in the management of HAE and underscore the broader potential of in vivo gene editing for genetic disorders.