Acoramidis Reduces Atrial Fibrillation Burden in ATTR-CM: ESC 2025 Insights

In this ESC 2025 CardioNerds discussion, CardioNerds Fellows Drs. Georgia Vasilakis Tsatiris and Anna Radhakrishnan interview Dr. Kevin Alexander, Assistant Professor of Cardiovascular Medicine at Stanford, about the latest findings from the ATTRibute-CM trial. Dr. Alexander, an expert in cardiac amyloidosis, explains that the phase 3 trial evaluated the efficacy of Acoramidis—a highly selective Transthyretin stabilizer—in patients with wild-type or hereditary ATTR-CM, showing significant benefits in cardiovascular outcomes. The team highlights a new post hoc analysis presented at ESC 2025, which focused on atrial arrhythmias, a common and burdensome comorbidity in ATTR-CM. This analysis is among the first to assess how disease-modifying therapy like Acoramidis may reduce atrial fibrillation and flutter burden in this patient population.

Transcript: 

CardioNerds: Hi everyone. My name is Georgia Vasilakis Tsatiris. I’m a chief medical resident at the University of Pittsburgh Medical Center and a fellow of the CardioNerds Academy.

Anna Radhakrishnan: Hi everyone. My name is Anna Radhakrishnan. I’m a third-year internal medicine resident and an incoming cardiology fellow at the Mount Sinai Hospital, and like Georgia, a CardioNerds Academy fellow. We are so excited to be back with Dr. Kevin Alexander today to discuss the latest results coming out of ESC 2025 [European Society of Cardiology Congress 2025]. Dr. Alexander is an assistant professor of cardiovascular medicine at Stanford University School of Medicine. While he sees a wide variety of advanced heart failure in transplant cases clinically, Dr. Alexander has this particular expertise in diagnosing and treating cardiac amyloidosis, a common rare disease that is an underdiagnosed cause of heart failure. Dr. Alexander is at the forefront of enhancing our understanding of this condition with grant support from the NIH and AHA [American Heart Association] among other sources. Dr. Alexander, we are all so excited to learn from you once again, and great to see you again.

Dr. Kevin Alexander: Thanks, Anna. Thanks, Georgia. Great to be here.

CardioNerds: Today we’ll be discussing cardiac amyloidosis updates from ESC 2025, specifically new analysis from the ATTRibute-CM trial. So to get us all up to speed, Dr. Alexander, could you briefly summarize the design and top-line results of the phase 3 ATTRibute-CM trial?

Dr. Kevin Alexander: Certainly, yes. ATTRibute-CM was a phase 3 randomized controlled trial studying patients with either wild-type or hereditary ATTR [transthyretin amyloidosis] in seeing the role of acoramidis for treating these patients. Acoramidis is a highly selective near complete TTR [transthyretin] stabilizer, and in the phase 3 ATTRibute-CM study, had strong clinical trial results for hard cardiovascular outcomes, cardiovascular hospitalizations and mortality, as well as other secondary end points. That’s led to the approval of acoramidis to treat ATTR cardiac amyloidosis patients in the US, Europe, and Japan.

Anna Radhakrishnan: That’s great. Thanks for the recap. So your latest study that you presented at ESC ’25 presents post hoc analyses, focused particularly on atrial arrhythmia, so atrial fibrillation and flutter. What was the rationale for this focus and how do these analyses differ from the prior ones in the ATTRibute-CM program?

Dr. Kevin Alexander: By way of background, it’s important to note that about two-thirds of ATTR-CM patients have concomitant atrial fibrillation, and that can confer additional morbidity and mortality, as it does for other cardiac conditions. There’s been a lot of analysis of ATTRibute-CM and other phase 3 amyloid clinical trials. I’ve looked at outcomes such as cardiovascular mortality and survival, but [have] not [seen] as much data about the impact of therapy on atrial arrhythmia burden. The goal of this analysis was really to look at post hoc subgroup data, specifically addressing the burden of atrial arrhythmias in this trial population.