This study focuses on Transthyretin Amyloidosis with Cardiomyopathy, a condition where abnormal proteins build up in the heart muscle, affecting its function. The study will test a new medication called Nucresiran (also known as ALN-TTRSC04) compared to placebo to determine if it can reduce deaths and heart-related medical events in patients with this condition.

The medication Nucresiran is given as an injection using a pre-filled syringe. The study aims to evaluate how well this new treatment works in patients who have heart problems related to protein buildup in their heart tissue. Some participants will receive the study medication, while others will receive a placebo.

During the study, doctors will monitor patients’ heart health and track any heart-related hospitalizations or urgent care visits. The study will also look at how the treatment affects patients’ quality of life and overall survival. Patients may continue taking their regular heart failure medications and other approved treatments for their condition while participating in the study.