Intellia Therapeutics announced positive three-year follow-up data from the Phase 1 portion of its ongoing Phase 1/2 study of lonvoguran ziclumeran (lonvo-z) in patients with Hereditary Angioedema (HAE). The data, presented at the European Academy of Allergy and Clinical Immunology (EAACI) Congress 2025, showed a 98% mean reduction in monthly HAE attack rate across all ten participants, who remained attack-free and treatment-free for a median of 23 months. The company also announced the completion of screening for its Phase 3 HAELO trial ahead of schedule.
This news is particularly encouraging for HAE patients, who often experience a diminished quality of life due to the unpredictable nature of attacks and the burden of continuous treatment. The potential for a one-time therapy like lonvo-z to eliminate both the attacks and the need for ongoing medication represents a significant step towards improving patients’ lives and overall well-being. This also reduces the long-term costs associated with chronic HAE management, offering a potential benefit for payers. The faster-than-expected screening completion for the Phase 3 trial indicates strong patient and physician interest in this novel treatment approach.
The Phase 1 study evaluated three different dosages of lonvo-z (25mg, 50mg, and 75mg). All doses demonstrated a sustained reduction in plasma kallikrein protein, the precursor to the protein that triggers HAE attacks. Importantly, lonvo-z continues to exhibit a favorable safety profile, with mostly mild and manageable infusion-related reactions. No serious adverse events related to the treatment were reported, further reinforcing the therapy’s potential. The Phase 3 HAELO trial is evaluating the 50mg dose. New data from the Phase 2 portion of the ongoing Phase 1/2 study is expected in the second half of 2025, and Intellia plans to submit a biologics license application in 2026, aiming for a U.S. launch in 2027.
The positive long-term data and rapid advancement of the Phase 3 trial reinforce the potential of lonvo-z to become a first-in-class, one-time treatment for HAE. This could significantly alter the treatment landscape for HAE, offering patients a transformative approach to managing their condition. The upcoming Phase 3 results will be crucial in confirming the efficacy and safety observed in earlier trials and paving the way for regulatory approval and potential market entry.
Jon Napitupulu is Director of Media Relations at The Clinical Trial Vanguard. Jon, a computer data scientist, focuses on the latest clinical trial industry news and trends.
