Intellia Therapeutics Announces FDA Lift of Clinical Hold on MAGNITUDE Phase 3 Clinical Trial in ATTR-CM

CAMBRIDGE, Mass., March 02, 2026 (GLOBE NEWSWIRE) -- Intellia Therapeutics, Inc. (Nasdaq: NTLA), a leading biopharmaceutical company focused on revolutionizing medicine leveraging CRISPR gene editing and other core technologies, today announced that the U.S. Food and Drug Administration (FDA) has removed the clinical hold on the Investigational New Drug application (IND) for the MAGNITUDE Phase 3 clinical trial of nexiguran ziclumeran (nex-z) for patients with transthyretin amyloidosis with cardiomyopathy (ATTR-CM).

“We are very pleased to have aligned with the FDA on the path forward for our MAGNITUDE clinical trial, with measures designed to further enhance patient safety and allow us to continue to investigate nex-z in a broad ATTR-CM population,” said Intellia President and Chief Executive Officer John Leonard, M.D. “With the resolution in January of the clinical hold on our MAGNITUDE-2 Phase 3 trial for patients with hereditary ATTR with polyneuropathy, our attention now turns to completing enrollment in both ongoing trials. We appreciate the FDA’s responsiveness throughout this process and thank the many investigators and patients who are participating in these trials.”

The clinical holds on the INDs for MAGNITUDE and MAGNITUDE-2 were imposed by the FDA on October 29, 2025, following the observation of Grade 4 liver transaminases and increased total bilirubin in a patient who was dosed with nex-z in MAGNITUDE that met the trial’s protocol-defined pausing criteria. The company has aligned with the FDA on mitigation measures for MAGNITUDE and MAGNITUDE-2 that include enhanced monitoring of liver laboratory tests, guidance for short-term steroid treatment if elevated liver transaminases are observed in the initial period following dosing and the exclusion of patients with certain liver abnormalities. For MAGNITUDE, additional exclusion criteria are being incorporated for patients with a recent history of cardiovascular instability and those with ejection fraction <25% at the time of screening. Intellia is engaged with clinical trial investigators, ethics committees, international regulatory authorities and other stakeholders to resume enrollment activities in MAGNITUDE and MAGNITUDE-2.

MAGNITUDE is a randomized, double-blind, placebo-controlled trial evaluating the efficacy and safety of nex-z in approximately 1,200 patients with ATTR-CM. The primary endpoint of the trial is based on a composite measure of cardiovascular-related events, including mortality. Adult patients with ATTR-CM are randomized 2:1 to receive a single 55 mg infusion of nex-z or placebo. For more information on MAGNITUDE (NCT06128629).

MAGNITUDE-2 is a randomized, double-blind, placebo-controlled trial evaluating the efficacy and safety of nex-z in approximately 60 patients with hereditary ATTR amyloidosis with polyneuropathy (ATTRv-PN). The primary endpoints of the study are a change in modified neuropathy impairment score and a change in serum TTR levels. Adult patients with ATTRv-PN are randomized 1:1 to receive a single 55 mg infusion of nex-z or placebo. For more information on MAGNITUDE-2 (NCT06672237).

About Nex-z
Based on Nobel Prize-winning CRISPR/Cas9 gene editing technology, nex-z has the potential to become the first one-time treatment for transthyretin (ATTR) amyloidosis with cardiomyopathy (ATTR-CM) and/or hereditary ATTR with polyneuropathy (ATTRv-PN). Nex-z is designed to inactivate the TTR gene that encodes for the transthyretin (TTR) protein and is being investigated in MAGNITUDE and MAGNITUDE-2, Phase 3 clinical trials in ATTR-CM and ATTRv-PN, respectively. Interim Phase 1 clinical data showed the administration of nex-z led to consistent, deep and long-lasting TTR reduction. Nex-z has received an Orphan Drug and RMAT Designation from the U.S. Food and Drug Administration (FDA) and an Orphan Drug Designation (ODD) from the European Commission. Intellia leads development and commercialization of nex-z as part of a multi-target discovery, development and commercialization collaboration with Regeneron Pharmaceuticals, Inc. 

About Intellia Therapeutics
Intellia Therapeutics, Inc. (Nasdaq: NTLA) is a leading clinical-stage biopharmaceutical company focused on revolutionizing medicine leveraging CRISPR gene editing and other core technologies. The company’s mission is to transform the lives of people with severe diseases by developing and commercializing potentially curative treatments. With deep scientific, technical and clinical development experience, Intellia aims to reset the standard for medicine by durably treating the root causes of disease.