Cardiac Magnetic Resonance and Echocardiography Study With Acoramidis (ASCEND-ATTR)

An Open-Label Study to Investigate the Long-Term Effects of Acoramidis on Cardiac Function, Structure and Cardiac Amyloid Burden in Participants With Transthyretin Amyloid Cardiomyopathy (ATTR-CM)

The study aims to evaluate the effect of acoramidis on cardiac functional and structural improvement in participants with ATTR-CM.

Study Overview

• Status: Not yet recruiting
• Conditions: Amyloidosis; Transthyretin Amyloidosis; Transthyretin Amyloidosis Cardiomyopathy (ATTR-CM); Amyloid Cardiomyopathy
• Intervention / Treatment: Drug: Acoramidis (AG10) oral tablet

Detailed Description

Study AG10-404 is an open-label study to investigate the long-term effects of acoramidis on cardiac functional and structural improvement, and the effects on cardiac amyloid burden in participants with ATTR-CM using two types of imaging, cardiac MRI and echocardiograms to track changes in heart structure and amyloid buildup over time.

Up to approximately 150 participants (ages 18-80) will be enrolled. Participants will receive study drug (712mg equivalent to 800mg of acoramidis hydrochloride) orally twice daily from Day 1 through Month 36. The study duration for an individual participant is approximately 38 months, including up to 45 days for screening, 36 months for open-label treatment and 1 month follow-up after the last dose of study drug. In-clinic visits will occur at Day 1, Day 28, Month 6, and every 6 months up to Month 36. Phone visits will occur at Month 3 and every 6 months thereafter up to Month 33. Participants will be followed throughout their participation in this study and for 30 days (+7 days) after the last dose of study drug.

• Study Type: Interventional
• Enrollment (Estimated): 150
• Phase: Phase 4

Contacts and Locations

• Study Contact: Name: Medical Information; Phone Number: 1-844-550-2246; Email: medinfo@bridgebio.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Key Inclusion Criteria:

• Participants aged 18 to 80
• Confirmed diagnosis of ATTR-CM requiring targeted therapy
• At screening: New York Heart Association (NYHA) Class I/II; estimated glomerular filtration rate (eGFR) ≥40 mL/min/1.73m2; left ventricular ejection fraction (LVEF) >35%; left ventricular (LV) wall thickness ≥12 mm.
• Heart failure condition has been clinically stable for at least 6 weeks prior to screening.

Key Exclusion Criteria:

• Current or planned implantation of a cardiac implantable electronic device (eg, pacemaker, implantable cardiac defibrillator).
• Acute myocardial infarction, acute coronary syndrome or coronary revascularization, or experienced stroke or transient ischemic attack within 90 days prior to screening.
• Hemodynamic instability.
• Likely to undergo heart transplantation within 12 months from screening.
• Confirmed diagnosis of AL amyloidosis at screening.
• At screening: NYHA Class III/IV; National Amyloidosis Center (NAC) Stage 3.
• Prior or current treatment with acoramidis.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• 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: Acoramidis (AG10); Open-label study where all participants will receive acoramidis (AG10) during the study	Drug: Acoramidis (AG10) oral tablet; Study drug is defined as acoramidis 712 mg (equivalent to 800 mg acoramidis HCl) taken orally twice daily for 36 months of open label treatment.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To assess the effect of acoramidis on cardiac function improvement by CMR in participants with ATTR-CM.	Change from baseline in left ventricular ejection fraction (LVEF) or left ventricular stroke volume index (LVSVi) at Month 36.	Month 36

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To assess the effect of acoramidis on cardiac function improvement or stabilization by CMR in participants with ATTR-CM.	Change from baseline in LVEF and LVSVi at Month 36	Month 36
To assess the effect of acoramidis on cardiac function stabilization by CMR in participants with ATTR-CM.	Change from baseline in LVEF and LVSVi at Month 36	Month 36
To evaluate the effect of treatment with acoramidis on individual parameters of left ventricular systolic function by CMR in participants with ATTR-CM	Mean change from baseline in LVEF, LVSVi, left ventricular global longitudinal strain (LVGLS) at Month 36	Month 36
To evaluate the effect of acoramidis on cardiac structure by CMR in participants with ATTR-CM	Mean change from baseline in left ventricular mass index (LVMi) at Month 36	Month 36
To evaluate the effect of treatment with acoramidis on cardiac amyloid burden by CMR in participants with ATTR-CM	Mean change from baseline in extracelluar volume (ECV) at Month 36	Month 36

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Exploratory Outcome Measure	To evaluate the effect of acoramids on various biomarkers and cardiac thansthoracic echocardiogram	At Month 12, 24 and 36

Collaborators and Investigators

• Sponsor: Eidos Therapeutics, a BridgeBio company

Study record dates

Study Major Dates

• Study Start (Estimated): July 1, 2026
• Primary Completion (Estimated): August 1, 2030
• Study Completion (Estimated): November 1, 2030

Study Registration Dates

• First Submitted: July 6, 2026
• First Submitted That Met QC Criteria: July 6, 2026
• First Posted (Actual): July 10, 2026

Study Record Updates

• Last Update Posted (Actual): July 10, 2026
• Last Update Submitted That Met QC Criteria: July 6, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: amyloidosis; TTR; cardiomyopathy; Amyloid; ATTR-CM
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Cardiovascular Diseases; Mental Disorders; Heart Diseases; Neuromuscular Diseases; Metabolism, Inborn Errors; Genetic Diseases, Inborn; Metabolic Diseases; Peripheral Nervous System Diseases; Neurocognitive Disorders; Dementia; Tauopathies; Neurodegenerative Diseases; Heredodegenerative Disorders, Nervous System; Proteostasis Deficiencies; Amyloid Neuropathies; Amyloidosis, Familial; Congenital, Hereditary, and Neonatal Diseases and Abnormalities; Nutritional and Metabolic Diseases; Alzheimer Disease; Cardiomyopathies; Amyloidosis; Amyloid Neuropathies, Familial; Amyloidosis, Hereditary, Transthyretin-Related; Pharmaceutical Preparations; Dosage Forms; Tablets; attruby
• Other Study ID Numbers: AG10-404; 2026-526068-19-00 (Ctis); U1111-1339-5700 (Other Identifier: WHO UTN)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

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