A Phase 3 Study of NTLA-2001 in ATTRv-PN

MAGNITUDE-2: A Phase 3, Multinational, Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Efficacy and Safety of NTLA-2001 in Participants With Hereditary Transthyretin Amyloidosis With Polyneuropathy (ATTRv-PN)

This study will be conducted to evaluate the efficacy and safety of a single dose of nexiguran ziclumeran (NTLA-2001) compared to placebo in participants with ATTRv-PN.

This is a multinational, multicenter, double-blind, placebo-controlled study in approximately 60 participants, who will be randomized 1:1 to receive a single infusion of either nexiguran ziclumeran or placebo. To ensure all participants will have the potential to receive nexiguran ziclumeran, participants will have the option to cross over to the opposite study arm at Month 12 or Month 18, depending on study criteria.

Inclusion Criteria:

• Diagnosis of ATTRv-PN
• Karnofsky Performance Status (KPS) ≥ 60

Exclusion Criteria:

• Other causes of amyloidosis (amyloidosis caused by non-TTR protein)
• Other known causes of sensorimotor or autonomic neuropathy
• Diabetes mellitus
• New York Heart Association Class III or IV heart failure
• Liver failure
• Hepatitis B, hepatitis C or human immunodeficiency virus (HIV) infection
• Prior receipt of a TTR silencer (Small interfering RNA (siRNA) or Antisense oligonucleotides (ASOs))
• Estimated Glomerular Filtration Rate < 30 mL/min/1.73 m2
• Unable or unwilling to take vitamin A supplementation for the duration of the study
• History of liver disease