Intellia Therapeutics has announced positive topline results from the Phase III HAELO trial of its in vivo CRISPR/Cas9 gene editing therapy, lonvo-z (NTLA-2002), for the treatment of hereditary angioedema (HAE). The study met its primary endpoint, demonstrating that a single 50 mg dose reduced the frequency of HAE attacks by 87% compared to placebo over a 24-week efficacy assessment period. The therapy also achieved all key secondary endpoints, with 62% of treated patients experiencing no attacks and requiring no rescue medication during that period, versus 11% in the placebo group. Lonvo-z was well-tolerated, with all adverse events being mild or moderate in severity.

Based on the data, Intellia plans to submit a rolling Biologics Licence Application (BLA) to US regulators, with completion expected in H2 2026 and potential commercial launch in H1 2027. Lonvo-z is designed to knock out the KLKB1 gene to reduce kallikrein activity, thereby preventing excessive bradykinin production that drives HAE attacks. If approved, it would be the first one-time, potentially curative in vivo gene editing therapy for HAE, a rare genetic disease characterised by recurrent, severe swelling attacks.

According to PharmCube's NextBiopharm® database, nine other gene therapies are under development in HAE, although none have entered human trials. Click here to request a free trial for NextBiopharm®.