A single treatment with the CRISPR-Cas9 based gene editing therapy, NTLA-2002, offers a potential functional cure for hereditary angioedema (HAE), potentially replacing the need for daily medication. The Phase 2 study, published in the New England Journal of Medicine, confirms earlier findings and demonstrates significant reductions in angioedema attacks following a single dose of the gene editing therapy.
The double-blind, placebo-controlled study, an expansion of the Phase 1 trial, involved 27 patients and tested two different dosages of NTLA-2002 compared to placebo. Researchers, led by Amsterdam UMC, found that both dosages led to a reduction in angioedema attacks and a sustained reduction in kallikrein levels, a crucial mediator of swelling in HAE patients.
Impact on Kallikrein Levels
"This reduction is perhaps the most crucial as it shows us that the therapy is working. Kallikrein acts as messenger that triggers swelling and in patients with HAE, this protein is basically let loose. The fact that we can reduce its presence tells us that we're on the right track," says Dr. Hilary Longhurst, an honorary senior lecturer at the University of Auckland.
HAE affects an estimated 50,000 patients worldwide, often leading to misdiagnosis due to its rarity. The trial included national excellence centers from the United Kingdom, New Zealand, Australia, Germany, and France, with industry sponsorship from Intellia, based in the United States.
Hope for HAE Patients
"For many decades, patients with HAE were faced with a very limited number of treatment options to control angioedema attacks. The prospect of a potential, functional cure following a single-time treatment is overwhelming both for patients and physicians," says Dr. Danny Cohn, internist at Amsterdam UMC and first author of the study.
Dr. Padmalal Gurugama, consultant in clinical immunology and allergy at Cambridge University Hospitals NHS Foundation Trust, described Phase 2 of the trial as a "fantastic team effort" and emphasized the real hope it offers to patients with limited treatment options.
Next Steps
The CRISPR-Cas9 therapy NTLA-2002 is now moving into Phase 3 of clinical development, with a larger patient cohort and continued collaboration among the international research team.
