On April 27, 2026, Intellia Therapeutics reported that its Phase 3 HAELO trial of lonvoguran ziclumeran (lonvo-z) — a one-time, in-body CRISPR gene-editing therapy for hereditary angioedema (HAE) — met its primary endpoint and all key secondary endpoints. In the 80-patient, randomized, double-blind trial, a single intravenous infusion of lonvo-z cut the rate of debilitating swelling attacks by 87% compared with placebo in the primary observation window (weeks 5 through 28). Sixty-two percent of patients who received the therapy were completely attack-free and had stopped all preventive medications in that period. The safety profile was clean: all reported side effects were mild or moderate, with no serious adverse events, and infusion-related reactions, headache, and fatigue were the most common complaints.
Intellia did not wait to act: the same day it released the results, the company initiated a rolling Biologics License Application (BLA) submission to the U.S. Food and Drug Administration (FDA). The rolling filing is enabled by lonvo-z's Regenerative Medicine Advanced Therapy (RMAT) designation, which allows the FDA to review completed sections as they arrive rather than waiting for a single complete package. Intellia expects to finish the full submission in the second half of 2026 and, if approved, to launch lonvo-z commercially in the first half of 2027 — which would make it the first approved in-body CRISPR medicine and, for the roughly one-in-50,000 Americans with HAE, a potential one-time replacement for drugs they now take every week or two for life.
