Clinical Research Directory

Inclusion Criteria: 1. Established diagnosis of ATTR-CM with either wild-type TTR or a variant TTR genotype. 2. History of heart failure evidenced by at least 1 prior hospitalization for heart failure or clinical evidence of heart failure without prior heart failure hospitalization manifested by signs or symptoms of volume overload or elevated pressures or heart failure symptoms that required or requires ongoing treatment with a diuretic. 3. New York Heart Association Class I-III symptoms due to ATTR-CM. 4. On stable doses of cardiovascular medical therapy. 5. Completed ≥ 150 meters on the 6MWT on 2 tests prior to Day 1. 6. Left ventricular (LV) wall (interventricular septum or LV posterior wall) thickness ≥ 12 millimeters. 7. Biomarkers of myocardial wall stress: N-terminal pro-brain-type natriuretic pep (NT-proBNP) level ≥ 300 picograms/milliliter (pg/mL). Exclusion Criteria: 1. Acute myocardial infarction, acute coronary syndrome or coronary revascularization, or experienced stroke or transient ischemic attack within 90 days prior to screening. 2. Hemodynamic instability at screening. 3. Likely to undergo heart transplantation within a year of screening. 4. Current treatment with marketed drug products and other investigational agents for the treatment of ATTR-CM. 5. Current treatment with calcium channel blockers with conduction system effects (for example, verapamil, diltiazem). The use of dihydropyridine calcium channel blockers is allowed. 6. Confirmed diagnosis of light-chain (AL) amyloidosis. 7. Biomarkers of myocardial wall stress: NT-ProBNP ≥ 8,500 pg/mL. 8. Measure of kidney function, estimated glomerular filtration rate by Modification of Diet in Renal Disease formula \< 30 mL/minute/1.73 meters squared.