Exploring Biomarkers in Hereditary Transthyretin Amyloidosis (ELBA)

Exploring Biomarkers in Hereditary Transthyretin Amyloidosis: From Clinical Severity Assessment to New Disease Mechanisms

Hereditary transthyretin amyloidosis (ATTRv, v for variant) is a severe and heterogeneous systemic condition due to mutations in the transthyretin (TTR) gene.

The availability of disease-modifying therapies has led to an urgent need to have reliable biomarkers capable of assessing the clinical severity of the disease and of monitoring the efficacy of pharmacological treatment. At the same time, early markers for the clinical onset of ATTRv amyloidosis in presymptomatic subjects are needed to enable earlier initiation of anti-amyloid therapy.

In this project the investigators seek to achieve three main goals: to identify and validate disease severity biomarkers in symptomatic patients; to establish disease onset biomarkers of ATTRv amyloidosis in presymptomatic subjects; to explore new pathogenetic mechanisms underlying this multisystem disorder, such as mitochondrial dysfunction and immune response.

Study Overview

• Status: Recruiting
• Conditions: Hereditary Transthyretin Amyloidosis
• Intervention / Treatment: Diagnostic test: Assessment of disease biomarkers

Detailed Description

Hereditary transthyretin amyloidosis is a severe and heterogeneous systemic condition due to mutations in the transthyretin (TTR) gene. This autosomal-dominant neurogenetic disorder is characterized by an adult-onset with variable penetrance and an extracellular deposition of amyloid in different organs with a prevalent involvement of the somatic and autonomic peripheral nervous system (PNS).

At the same time, the heart, the kidney, the gastro-intestinal system, and the eyes are frequently involved, leading to a lifethreatening multisystem disease with a huge clinical variability and course, and death within 10 years on average. The prevalence of the disease is highly variable between endemic and non-endemic countries and the global prevalence ranges from 5.526 to 38.468. However, the real numbers of ATTRv could even be higher, considering the missing diagnoses and pre-symptomatic carriers regularly followed in each centre. The last few years have been characterized by a significant change in disease management due to a deeper knowledge of the phenotype-genotype correlations and most importantly to the availability of disease-modifying therapies (DMTs). This raises the need for reliable disease biomarkers, in order to monitor the efficacy of the pharmacological treatment and the progression of the disease but also to identify the disease onset in the presymptomatic carriers of TTR gene pathogenic variants.

While enormous progress has been made in diagnostics and treatment in ATTRv, advances in the identification of biomarkers useful for assessing the severity of the disease and the efficacy of pharmacological approaches have not been parallel to this so far. Once molecular diagnosis has been established, ATTRv patients are evaluated in clinical practice and in clinical trials through clinical scales such as the Familial Amyloid Polyneuropathy (FAP) staging system, the Polyneuropathy Disability (PND) score, the Neuropathy Impairment Score (NIS) and its subset, the NIS-lower limbs (NIS-LL) score, and the Norfolk Quality of Life-Diabetic Neuropathy (QoL-DN) questionnaire. However, these purely clinical scales detect a change only when patients have already progressed clinically. It would be desirable to have outcome measures in order to effectively treat presymptomatic patients with a high risk of future clinical worsening.

Furthermore, investigating extraneurological involvement in ATTRv can help identifying disease severity biomarkers and shed light on new general and specific pathogenetic pathways besides those already known. In this context, neurofilament light chain (NfL), a neuronal cytoplasmic protein highly expressed in large calibre myelinated axons, has emerged as a good candidate as a disease biomarker in ATTRv, suggesting a key role in monitoring disease progression.

Providing information about somatic and autonomic small fiber, skin biopsy appears to be a minimally invasive exam able to disclose pathological changes several years before the onset of symptoms. Skeletal muscle can be secondarily involved in ATTRv amyloidosis, as already described for other inherited neuropathies. In this context, muscle MRI can represent a useful tool to evaluate the progression of the pathology.

The main purpose of our study is the definition and validation of disease severity biomarkers in symptomatic patients, able to describe the natural history of the disease and to monitor the efficacy of drug treatments currently available or to be evaluated in future clinical trials. At the same time, the investigators aim to identify measurable criteria capable of early identifying disease onset in presymptomatic subjects. Lastly, the investigators will explore new potentially pathogenetic mechanisms associated with ATTRv, such as mitochondrial dysfunction and the role of inflammation in order to identify a rationale for future innovative therapeutic strategies.

• Study Type: Interventional
• Enrollment (Estimated): 80
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Guido Alessandro Primiano; Phone Number: +39 0630154279; Email: guidoalessandro.primiano@policlinicogemelli.it

Study Locations

• Italy
  • ID
    • Roma, ID, Italy, 00168
      • Recruiting
      • Fondazione Policlinico Universitario Agostino Gemelli IRCCS
      • Contact: Guido Alessandro Primiano; Phone Number: +39 0630154279; Email: guidoalessandro.primiano@policlinicogemelli.it

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

1. Molecularly defined patients with hereditary transthyretin amyloidosis, carrying TTR pathogenic variants
2. Presymptomatic carriers of the pathogenic variants in TTR gene
3. Subjects aged 18 years or older
4. Evidence of a personally signed and dated informed consent document indicating that the subject has been informed of all pertinent aspects of the study

Exclusion Criteria:

1. Inability to understand or unwilling to follow the study requirements including attendance at the study center, completion of questionnaires and participation in laboratory testing as called for by the protocol
2. Inability to sign an informed consent
3. Severe psychiatric diseases

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Diagnostic
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Assessment of disease biomarkers	Diagnostic test: Assessment of disease biomarkers; Assessment of serum, histological and radiological biomarkers

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Circulating disease biomarkers in ATTRv amyloidosis	Validation of serum biomarkers of disease (DJ-1, cystatin C, calbindin, uromodulin, GDF-15 and NfL) in patients with ATTRv (baseline assessment). Change from baseline in serum levels of disease biomarkers (DJ-1, cystatin C, calbindin, uromodulin, GDF-15 and NfL) at different time points through week 96.	Baseline, weeks 24, 48, 72, 96
Neuropathological biomarkers in ATTRv amyloidosis	Baseline assessment of intraepidermal nerve fiber density (IENFD). Change from baseline in intraepidermal nerve fiber density (IENFD) at week 96.	Baseline, week 96
Radiological biomarkers (muscle MRI) in ATTRv amyloidosis	Baseline assessment of total fatty infiltration score and STIR sequences. Change from baseline in total fatty infiltration score and STIR sequences at week 96.	Baseline, week 96
Circulating disease biomarkers in presymptomatic individuals	Change from baseline in serum levels of disease biomarkers (DJ-1, cystatin C, calbindin, uromodulin, GDF-15 and NfL) at different time points through week 96.	Baseline, weeks 24, 48, 72, 96
Neuropathological biomarkers in presymptomatic individuals	Baseline assessment of intraepidermal nerve fiber density (IENFD). Change from baseline in intraepidermal nerve fiber density (IENFD) at week 96.	Baseline, week 96
Radiological biomarkers (muscle MRI) in presymptomatic individuals	Baseline assessment of total fatty infiltration score and STIR sequences. Change from baseline in total fatty infiltration score and STIR sequences at week 96.	Baseline, week 96

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Inflammatory profile in ATTRv amyloidosis	To document the contribution of inflammation in the ATTRv pathogenesis by assessing serum cytokine levels.	Baseline, week 96
Mitochondrial dysfunction in ATTRv amyloidosis	To document the contribution of mitochondrial dysfunction in the ATTRv pathogenesis by biochemical investigations on serum and muscle/skin.	Baseline

Collaborators and Investigators

• Sponsor: Fondazione Policlinico Universitario Agostino Gemelli IRCCS

Study record dates

Study Major Dates

• Study Start (Actual): May 1, 2023
• Primary Completion (Estimated): December 31, 2025
• Study Completion (Estimated): April 30, 2026

Study Registration Dates

• First Submitted: June 7, 2023
• First Submitted That Met QC Criteria: June 26, 2023
• First Posted (Actual): July 3, 2023

Study Record Updates

• Last Update Posted (Actual): September 24, 2024
• Last Update Submitted That Met QC Criteria: September 23, 2024
• Last Verified: September 1, 2024

More Information

Terms related to this study

• Keywords: biomarkers; neurogenetics; neuromuscular disorders; mitochondrial dysfunction; hereditary transthyretin amyloidosis
• Additional Relevant MeSH Terms: Metabolic Diseases; Nervous System Diseases; Genetic Diseases, Inborn; Neuromuscular Diseases; Neurodegenerative Diseases; Peripheral Nervous System Diseases; Proteostasis Deficiencies; Metabolism, Inborn Errors; Heredodegenerative Disorders, Nervous System; Amyloidosis, Familial; Amyloid Neuropathies; Amyloidosis; Amyloid Neuropathies, Familial
• Other Study ID Numbers: 5470

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No