FDA accepts Intellia’s lonvo-z BLA for HAE with Priority Review

Intellia Therapeutics said September 8 that the U.S. Food and Drug Administration accepted its Biologics License Application for lonvoguran ziclumeran, or lonvo-z, for hereditary angioedema and granted Priority Review. The FDA set a March 10, 2027 PDUFA target action date. The milestone advances the application into review; it is not an FDA approval.

Priority Review sets a March 2027 clock

The FDA advised Intellia that it is not currently planning to hold an advisory committee meeting to discuss the application, according to the company. Intellia says that, if approved, lonvo-z would be the world’s first in vivo CRISPR-based therapy and the only one-time treatment for HAE. Those potential distinctions remain company claims contingent on approval.

The application is supported by positive results from the global Phase 3 HAELO trial. The study enrolled 80 patients in nine months and evaluated the efficacy and safety of a one-time 50-milligram dose in adults and adolescents aged 16 years and older with Type 1 or Type 2 HAE.

HAELO Phase 3 underpins the application

Intellia reported that HAELO met its primary and all key secondary endpoints. Mean monthly attacks were reduced by 87% versus placebo during the weeks 5 through 28 efficacy evaluation period (p<0.0001). During the six-month efficacy evaluation period, 62% of patients receiving lonvo-z were entirely attack free and HAE therapy free, compared with 11% receiving placebo (p<0.0001).

As of the February 10, 2026 data cutoff, all patients who received lonvo-z at baseline or crossed over after week 28 remained free from long-term prophylaxis therapy, the company disclosed. That observation has a separate cutoff from the September regulatory announcement.

The company reported that the most common treatment-emergent adverse events occurring more frequently than with placebo from infusion through week 28 were infusion-related reactions, headache, fatigue, back pain and upper respiratory tract infection. All reported treatment-emergent adverse events were mild or moderate, according to the company disclosure.

Acceptance is not approval

The next dated regulatory milestone is the March 10, 2027 target action date. Neither the acceptance of the application nor Priority Review establishes that the FDA will approve lonvo-z.