Lonvo-z BLA Accepted by FDA With Priority Review for HAE

The US Food and Drug Administration (FDA) has accepted the Biologics License Application (BLA) for lonvoguran ziclumeran (lonvo-z) and granted it priority review for hereditary angioedema (HAE) in patients aged ≥ 16 years, setting a Prescription Drug User Fee Act (PDUFA) target action date of March 10, 2027, according to Intellia Therapeutics.¹

If approved, lonvo-z would become the first in vivo CRISPR-based therapy to reach the HAE market and the only one-time treatment option available to patients who currently manage the disease with chronic intravenous or subcutaneous prophylaxis. FDA has indicated it does not currently plan to convene an advisory committee to review the application.¹ The filing follows a phase 3 program in which the global HAELO trial enrolled 80 patients in 9 months.¹

"Today's announcement is exciting because it advances us one step closer to potentially having a one-time treatment option available for patients who continue to be burdened by this chronic disease,” said HAELO trial investigator Joshua Jacobs, MD, medical director of Allergy and Asthma Clinical Research, in a statement. ¹

Lonvo-z HAELO Trial Design and Primary Efficacy Results

The BLA is supported by data from the phase 3 HAELO trial, a global study evaluating a one-time 50 mg dose of lonvo-z in adults and adolescents aged ≥ 16 years with type 1 or type 2 HAE.² HAELO met its primary endpoint and all key secondary endpoints.²

Lonvo-z produced an 87% reduction in mean monthly attacks compared with placebo during the efficacy evaluation period spanning weeks 5 through 28 (P <.0001).² The KLKB1 gene-editing mechanism is designed to permanently lower plasma kallikrein activity following a single outpatient infusion.² Intellia frames the result as the clinical basis for a durable, one-time alternative to prophylaxis regimens administered as often as twice weekly or daily.²

Lonvo-z Secondary Endpoints and Safety Profile

Secondary results reinforced the primary finding. In the lonvo-z arm, 62% of patients remained entirely attack-free and free of HAE therapy for the 6-month efficacy evaluation period, compared with 11% of patients receiving placebo (P <.0001).¹ 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.¹

The safety profile was favorable through the data cutoff, according to Intellia.¹ Treatment emergent adverse events more common in the lonvo-z group than placebo included infusion-related reactions, headache, fatigue, back pain, and upper respiratory tract infection.¹ The company reported all treatment emergent adverse events as mild or moderate, with no serious adverse events observed in the lonvo-z arm.¹

Lonvo-z has received 5 regulatory designations to date, including Orphan Drug and Regenerative Medicine Advanced Therapy (RMAT) designations from FDA, Innovation Passport designation from the UK Medicines and Healthcare products Regulatory Agency, Priority Medicines designation from the European Medicines Agency, and Orphan Drug Designation from the European Commission.¹

"Today marks an important milestone for the patients we are committed to serving and for Intellia's pioneering work in the field of in vivo gene editing," said John Leonard, MD, president and chief executive officer at Intellia Therapeutics, in a statement.¹ "Backed by compelling phase 3 data, we believe lonvo-z could fundamentally change the way HAE is treated and are excited by its potential to become the world's first approved in vivo CRISPR-based therapy."¹

References

1. Intellia Therapeutics announces FDA acceptance of Biologics License Application with Priority Review for lonvoguran ziclumeran (lonvo-z) for hereditary angioedema (HAE). Published September 8, 2026. Intellia Therapeutics. Accessed September 8, 2026. https://www.globenewswire.com/news-release/2026/09/08/3357599/0/en/intellia-therapeutics-announces-fda-acceptance-of-biologics-license-application-with-priority-review-for-lonvoguran-ziclumeran-lonvo-z-for-hereditary-angioedema-hae.html

2. Banerji A. Single-Dose Lonvo-z Cuts HAE Attacks by 87% in Phase 3 Trial, With Aleena Banerji, MD. HCPLive. Published April 27, 2026. Accessed September 8, 2026. https://www.hcplive.com/view/single-dose-lonvo-z-cuts-hae-attacks-87-phase-3-trial-aleena-banerji-md