A phase 3 trial published by the New England Journal of Medicine found that a single in vivo gene-editing therapy sharply reduced attack rates in patients with hereditary angioedema compared with placebo.
Hereditary angioedema (HAE) is a rare genetic condition that causes sudden, severe swelling in the skin, gut, and airways — attacks that can be life-threatening and are often unpredictable. The New England Journal of Medicine has published full results from the HAELO trial, testing a new drug called lonvo-z, which edits a patient’s genes directly inside the body rather than in a laboratory setting.
In the randomised trial, patients who received lonvo-z had a much lower attack rate than those who received a placebo, according to the journal. The trial was phase 3 — the stage of clinical research that tests whether a treatment works reliably across a larger group of patients before regulators consider approving it for wider use.
In vivo gene editing means the therapy acts inside the living body, targeting a gene involved in the attack pathway — reducing the chemical signals that trigger swelling — rather than treating attacks after they have already begun. That’s a different approach from most current HAE treatments, which either try to prevent attacks with regular medication or treat them once they’ve begun.
HAE is caused by a deficiency or malfunction of a protein called C1-inhibitor, which normally controls inflammation. Without it working properly, patients can experience attacks with little warning.
The NEJM posted the full trial results and a research summary. Results from a single trial, however promising, do not mean a treatment is approved or available — regulatory review by bodies such as the Medicines and Healthcare products Regulatory Agency (MHRA) in the UK would follow before any drug reaches patients here.
Anyone living with HAE or seeking advice about a rare condition should speak to their GP or contact NHS 111 for guidance on specialist referral pathways.
Source: @NEJM