Study of ALXN2220 Versus Placebo in Adults With ATTR-CM

Inclusion Criteria:

Centrally confirmed diagnosis of ATTR-CM with either wild-type or variant TTR genotype
End-diastolic interventricular septal wall thickness ≥ 11 mm for women or ≥ 12 mm for men on echocardiography measured at Screening
NT-proBNP > 2000 pg/mL at Screening
Treatment with a loop diuretic for at least 30 days prior to Screening
History of heart failure NYHA Class II-IV at Screening
Life expectancy of ≥ 6 months as per the Investigator's judgment
Males and females of childbearing ability must use contraception

Exclusion Criteria:

Known leptomeningeal amyloidosis
Known light chain (AL) or secondary amyloidosis (AA), or any other form of systemic amyloidosis
Acute coronary syndrome, unstable angina, stroke, transient ischemic attack, coronary revascularization, cardiac device implantation, cardiac valve repair, or major surgery within 3 months of Screening
Uncontrolled clinically significant cardiac arrhythmia, per Investigator's assessment
LVEF < 30% on echocardiography
Renal failure requiring dialysis or an eGFR < 20 mL/min/1.73 m2 at Screening
Polyneuropathy with PND score IV