Transthyretin Amyloidosis

Transthyretin amyloidosis (ATTR) is a disease where the normally occurring transthyretin (TTR) protein falls apart and forms amyloid, a sticky plaque-like substance that accumulates in different organs in the body and can cause damage to the organ. There are two ways that the TTR protein can fall apart. One way occurs as a person ages, where the normal TTR protein can fall apart and form amyloid that may no longer be sufficiently cleared by the body. This type of ATTR is known as wild-type ATTR (ATTRwt). The other way occurs when a person inherits a defective TTR gene that causes the TTR protein to spontaneously fall apart. This form of the disease is known as variant ATTR (ATTRv) and can be detected in adults by a genetic test of their TTR gene before they age. Amyloid build-up in the heart causes the heart wall to become thick and stiff and can result in heart failure and even death. Accumulation of TTR amyloid in the heart is known as transthyretin amyloid cardiomyopathy or ATTR-CM. Amyloid can also deposit in the nerve tissues leading to nerve problems. Accumulation of TTR in the nerves is known as transthyretin amyloid polyneuropathy or ATTR-PN. Acoramidis is an experimental drug designed to bind tightly to TTR in the blood and stabilize its structure, so it does not form the harmful amyloid plaques that can cause damage to organs. This study is intended to determine if treatment with acoramidis in participants with ATTRv who have not yet developed any symptoms of disease can prevent or delay the development of ATTR-CM or ATTR-PN disease. If adults with an inherited defective TTR gene are treated early before any of the symptoms of disease have developed, it may be possible to delay the onset or prevent the disease entirely.

The MaesTTRo study aims to enroll a global cohort of patients with transthyretin (ATTR) amyloidosis to longitudinally observe the natural course of the disease and describe real-world treatment patterns and outcomes. In addition, information on the effectiveness of ATTR amyloidosis treatments, including eplontersen, which is a ligand-conjugated antisense oligonucleotide gene silencing treatment targeting activity against both the mutant and wild-type TTR protein, will be collected.

The overall objective of this DPSS is to describe the occurrence of pregnancy and maternal complications, adverse effects on the developing fetus and neonate, and adverse effects on the infant associated with exposure to eplontersen during pregnancy and/or lactation.

The aim of this observational cohort study is to characterise use of eplontersen in patients with prior liver transplant or with pre-existing severe hepatic impairment, as well as to assess long-term safety among all new users of eplontersen; all are areas of missing information Primary objectives are: 1. To describe demographic and clinical characteristics of patients at eplontersen initiation, including the prevalence of prior liver transplant (overall and by reason for liver transplant), and the prevalence of severe hepatic impairment; and to describe patients in these subgroups (prior liver transplant, severe hepatic impairment). 2. To describe long-term safety in patients who initiate eplontersen treatment, including onset of new clinical events, abnormal laboratory values and serious adverse events.

Transthyretin amyloidosis (ATTR) is an underdiagnosed condition that can present early as carpal tunnel syndrome, sometimes preceding cardiac involvement by several years. The recent emergence of new treatments underscores the importance of early diagnosis. Synovial biopsy performed during open carpal tunnel surgery is considered the gold standard for local screening, but it is less accessible, more difficult, and riskier to perform via endoscopy-a minimally invasive surgical technique that is currently the standard at our center and is becoming increasingly widespread. The anterior annular ligament of the carpus constitutes an alternative tissue to the synovium, easily accessible via endoscopy, safe, and standardizable. In this study, the systematic performance of an annular ligament biopsy in conjunction with a synovial biopsy during endoscopic carpal tunnel surgery would allow for the evaluation of the diagnostic concordance of the ligament biopsy by comparing it to the results obtained using the gold standard method. This strategy would also provide an opportunity to analyze the feasibility of systematic screening for ATTR on the ligament during endoscopic procedures. This approach could offer a practical and innovative method for the early identification of at-risk patients and facilitate appropriate and timely management of the condition.

This study aims to determine the positive predictive value of incidental cardiac uptake on bone scintigraphy for diagnosing transthyretin cardiac amyloidosis, in patients who underwent scintigraphy for reasons other than suspected amyloidosis. The study is an observational, descriptive, multicenter, national study using retrospective data from routine care. Patients with incidental cardiac uptake will be recalled for further diagnostic assessment.

This is a single center prospective study evaluating 124I-evuzumitide in patients with systemic amyloidosis. The purpose of this study is to 1) Establish the diagnostic accuracy of 124I-evuzumitide in cardiac amyloidosis 2) Evaluate extracardiac uptake 3) identify and characterize the distribution and uptake of 124I-evuzumitide in patients with transthyretin amyloid cardiomyopathy (ATTR-CM) and 4) Correlate the uptake with the structure and function of different organs, including the heart. To achieve these goals, eligible patients will undergo primarily hybrid positron emission tomography and magnetic resonance imaging (PET/MRI). In a subgroup of patients who are unable to undergo PET/MR, computed tomography will be used instead of MRI (i.e. PET/CT). In a subgroup of patients, repeat imaging with the same modality will be done at a interval of 6-12 months. Clinically available data (demographics, phenotype, imaging, laboratory) will also be collected to characterize the disease in each patient.

Descriptive cross-sectional study on 100 consecutive ATTRwt-CM patients reflecting all NAC stages aiming primarily to investigate ATTRwt-CM patient's quality of life (QoL) measures and their relation to ATTRwt-CM severity. Secondarily aiming to investigate the possibility to measure misTTR and fragTTR in plasma and urine and to detect fragTTR in endomyocardial biopsies from ATTRwt-CM patients. To investigate whether misTTR and fragTTR levels are correlated with ATTRwt-CM severity.

Recent studies have shown that transthyretin amyloidosis (ATTR) can sometimes cause a type of heart failure where the pumping function of the heart is normal, also known as Heart Failure with Preserved Ejection Fraction (HFpEF) or diastolic heart failure. In this single center diagnostic study, we will evaluate for ATTR in patients with HFpEF in order to to determine how frequently this occurs and how we can predict which heart failure patients may have TTR amyloidosis. Our goal is to identify amyloidosis in heart failure patients earlier so that they can start treatment.