The purpose of this study is to obtain safety, efficacy, and pharmacodynamic data on the
use of vutrisiran in patients with ATTR amyloidosis with cardiomyopathy who continued on
extended use of vutrisiran, or switched from patisiran.

A Study to Evaluate Vutrisiran in Patients With Transthyretin Amyloidosis With Cardiomyopathy

Transthyretin Amyloidosis (ATTR) With Cardiomyopathy

Vutrisiran

Clinical Trial Site

An Open-Label Extension Study to Assess the Safety and Efficacy of Vutrisiran in Patients With Transthyretin Amyloidosis With Cardiomyopathy (ATTR Amyloidosis With Cardiomyopathy)

An AE is any untoward medical occurrence in a patient or clinical investigational subject
administered a medicinal product and which does not necessarily have a causal
relationship with this treatment.

The KCCQ is a 23-item self-administered questionnaire quantifying 6 domains (symptoms,
physical function, quality of life, social limitation, self-efficacy, and symptom
stability) and 2 summary scores (clinical and overall summary [OS]). Scores are
transformed to a range of 0-100, in which higher scores reflect better health status.

NYHA classification grades the severity of heart failure symptoms into the following
stages: I (no symptoms; ordinary physical activity such as walking and climbing stairs
does not cause fatigue or dyspnea), II (symptoms with ordinary physical activity; walking
or climbing stairs rapidly, walking uphill, walking or stair climbing after meals, in
cold weather, in wind or when under emotional stress causes undue fatigue or dyspnea),
III (symptoms with less than ordinary physical activity; walking 1 to 2 blocks on the
level and climbing more than 1 flight of stairs in normal conditions causes undue fatigue
or dyspnea), IV (symptoms at rest; inability to carry on any physical activity without
fatigue or dyspnea).

NT-proBNP will be assessed through measurement of serum levels.

Troponin I will be assessed through measurement of serum levels.

All deaths, hospitalizations and urgent HF visits will be recorded throughout the study
as part of SAE and AE monitoring

Participants will receive vutrisiran 25 mg administered subcutaneously (SC) once every 3
months (q3M).