Acoramidis shows structural cardiac reversal in 54-month ATTR-CM data

BridgeBio Pharma has presented a substantial new dataset for acoramidis (Attruby) at the European Society of Cardiology Congress 2026, with analyses from the Phase 3 ATTRibute-CM trial and its open-label extension running to 54 months. The results, simultaneously published in the European Journal of Heart Failure, span cardiac structural remodelling, hospitalisation burden, genetic subgroup outcomes, and quality of life measures.

The most clinically striking finding came from the cardiac magnetic resonance imaging substudy. In a completer analysis, 54% of acoramidis-treated patients showed clinically meaningful improvement in left ventricular systolic function at Month 30, against 20% of placebo patients. At Month 42, 53% of continuously treated patients maintained that level of improvement. For context, BridgeBio reported that only 26% of a matched natural history cohort demonstrated similar improvement by Month 24, suggesting the effect exceeds what would be expected from the natural course of disease. Marianna Fontana of University College London, who presented the imaging data, said the findings support acoramidis as a therapy "capable of altering the trajectory of this otherwise progressive disease."

Hospitalisation and survival benefit

A post-hoc analysis quantified the aggregate disease burden using days lost to death and cardiovascular-related hospitalisation, a composite measure that folds in all-cause mortality, admission frequency, and length of stay. Treated patients lost an estimated 7.5% of days to these events through Month 30, versus 11.7% for those on placebo. On an observed basis, that translated to 38 additional days alive and out of hospital over 30 months, rising to 65 days at three years. Modelled projections extended the estimate to up to 94 days, though BridgeBio acknowledges these are modelled rather than directly observed figures.

The 54-month open-label extension data addressed a significant equity dimension in ATTR-CM research. The p.Val142Ile variant, which occurs in approximately 3-4% of people of Western African ancestry in the United States, is the most prevalent genetic form of the disease globally and has historically been under-represented in outcome trials. Across 35 p.Val142Ile patients receiving continuous acoramidis, all-cause mortality reached 30.4% through Month 54, compared with 66.7% in those who crossed over from placebo, a more than two-fold difference. Mortality rates in the placebo-to-acoramidis group were notably high, underscoring the cost of delayed treatment initiation in this subgroup.

Market context and competitive landscape

Acoramidis competes directly with tafamidis (Vyndaquel/Vyndamax), the Pfizer product that established TTR stabilisation as a viable treatment strategy in ATTR-CM. Pfizer's drug has held a dominant commercial position since its FDA approval in 2019, but acoramidis entered the market with regulatory labels in multiple jurisdictions specifying near-complete, meaning at least 90%, TTR stabilisation, a mechanistic differentiator BridgeBio is pressing hard in its commercial messaging.

The structural cardiac reversal signal, if it holds in the dedicated ASCEND-ATTR Phase 3b/4 study now enrolling, could sharpen that differentiation further. Reversal of cardiomyopathy rather than mere slowing of progression is a clinically meaningful distinction for cardiologists, though it is worth noting that the current CMR data comes from a substudy with completers rather than an intention-to-treat population, and post-hoc analyses carry inherent limitations.

Also presented at ESC were three posters from BridgeBio's collaboration with Yale's Cardiovascular Data Science Lab, showing that a computer vision AI-electrocardiogram algorithm could detect differential treatment effects over 30 months and that a federated AI network had identified a large burden of probable undiagnosed ATTR-CM across multiple US centres. These findings point toward earlier detection as a potential growth lever for the acoramidis franchise, given that diagnosis rates in ATTR-CM remain low relative to estimated prevalence.

BridgeBio has flagged the Heart Failure Society of America Annual Scientific Meeting in October 2026 as the next data readout window for Attruby.