A new study will evaluate the morphological and functional cardiac effects of patisiran in a group of patients with a mixed form of hereditary transthyretin amyloidosis (hATTR). The study is not yet recruiting.

According to the inclusion criteria, eligible participants will be at least 18 years old and have a diagnosis of hATTR with stage 1 or 2 polyneuropathy and New York Heart Association (NYHA) stage 1 and 2 cardiac disease.

Eligible participants must be prescribed patisiran for at least 12 months. However, the study protocol will exclude those receiving tafamidis simultaneously with patisiran, women of childbearing age, as well as people with claustrophobia and a metallic implant, which contraindicate magnetic resonance imaging (MRI).

The researchers will analyze the effects of patisiran on myocardial activity during inclusion as well as the routine consultation after 1 year of treatment. They will perform clinical and biological exams, electrocardiography, echocardiography, cardiac MRI, and scintigraphy, as well as a life quality questionnaire and a functional walking test.

Read more about hATTR treatment

The difference in longitudinal relaxation time, a process by which the net magnetization grows or returns to its initial maximum value parallel to Bo in an MRI, will be evaluated after 1 year as the primary outcome measure.

The researchers will also evaluate the difference in Kansas City Cardiomyopathy Questionnaire score, Perugini Grading Score, and distance obtained in the 6-minute walking test, as well as the value of the global longitudinal strain, the global left atrial longitudinal strain, the global strain of the right ventricular free wall, and the evolution of myocardial work between the inclusion and 12-month follow up as the secondary outcome measures.

The study is sponsored by the Rennes University Hospital and is set to start in July 2023. The estimated primary completion date as well as the estimated study completion date is July 2024.


Myocardial effects in patients with hATTR with polyneuropathy treated with patisiran (MyocardON-TTR). ClinicalTrials.gov. May 24, 2023. Last updated May 26, 2023. Accessed May 30, 2023.