Spectrum of Peripheral and Autonomic Neuropathies in Patients With aTTRwt Amyloidosis and Response to Patisiran Therapy

The study will consist of a baseline screening period and a 24-month treatment period. Eligible patient will receive patisiran administered as an IV infusion once every 21 days for a 24-month period. During the 24-month treatment period study patients will undergo assessments for efficacy and/or safety as outlined in the schedule of assessments with key efficacy assessments being performed prior to the first dose and proceeding as outlined in the schedule of assessments.