Alnylam Pharmaceuticals to Showcase New Analyses at Heart Failure 2026 Highlighting the Consistent Clinical Profile of Vutrisiran in ATTR-CM
Alnylam Pharmaceuticals (Nasdaq: ALNY) has announced that it will present a comprehensive set of new data analyses for vutrisiran in patients with transthyretin-mediated amyloidosis with cardiomyopathy (ATTR-CM) at Heart Failure 2026, a major scientific meeting organized by the European Society of Cardiology. The congress is scheduled to take place from May 9–12, 2026, in Barcelona, bringing together leading experts in cardiovascular medicine to discuss the latest advancements in heart failure and related conditions.
The upcoming presentations will focus on expanding the clinical understanding of vutrisiran, an RNA interference (RNAi) therapeutic designed to silence the transthyretin (TTR) gene, which plays a central role in the development of ATTR amyloidosis. This disease is characterized by the accumulation of misfolded TTR protein deposits in various organs, including the heart, leading to progressive dysfunction. ATTR-CM, which affects both hereditary and wild-type patient populations, is a complex and rapidly progressing condition often associated with high morbidity and mortality.
Patients with ATTR-CM frequently present with diverse and complicated clinical profiles, including multiple comorbidities and varying disease severity. As a result, there is a growing need for therapies that can effectively address the underlying cause of the disease while demonstrating consistent benefits across different patient subgroups. Alnylam’s data presentations at Heart Failure 2026 aim to address these challenges by providing deeper insights into the efficacy, safety, and real-world applicability of vutrisiran.
Central to these analyses are findings from the Phase 3 HELIOS-B clinical trial, a pivotal study evaluating the therapeutic impact of vutrisiran in patients with ATTR-CM. Previous results from HELIOS-B have supported the use of vutrisiran as a potential first-line treatment option, and the new analyses being presented will further characterize its clinical profile. These include evaluations of treatment effects in patients with a high disease burden, as well as those receiving concomitant therapies, offering a more nuanced understanding of how the drug performs in real-world clinical scenarios.
Vutrisiran is currently distinguished as the first and only TTR-silencing therapy for ATTR-CM that achieves rapid and sustained reduction of transthyretin at its source—namely, the liver. By targeting the production of TTR protein, the therapy addresses the root cause of amyloid deposition, potentially slowing or halting disease progression. This mechanism of action represents a significant advancement over traditional therapies that primarily focus on managing symptoms rather than modifying the underlying disease process.
Among the key analyses to be presented at the congress is a pharmacodynamic evaluation of TTR knockdown across various patient subgroups. This analysis will provide important insights into the consistency of vutrisiran’s biological activity, helping to determine whether its effects are uniform across different demographic and clinical populations. Such information is critical for optimizing treatment strategies and ensuring that a broad range of patients can benefit from the therapy.
Another important presentation will focus on the influence of vutrisiran on systolic blood pressure in patients with ATTR-CM. Cardiovascular parameters such as blood pressure are important indicators of disease progression and treatment response, and understanding how vutrisiran interacts with these variables can help clinicians better manage patient care. Additional analyses will examine the drug’s efficacy in patients with and without atrial fibrillation or flutter, conditions that are commonly observed in individuals with cardiac amyloidosis.
Safety remains a key consideration in the long-term management of chronic diseases like ATTR-CM. To this end, Alnylam will present a pooled safety analysis examining the effects of TTR-lowering therapies on vitamin A levels. Because transthyretin plays a role in the transport of vitamin A, reducing TTR levels can lead to decreased serum vitamin A. The analysis will evaluate whether this reduction is associated with clinical outcomes such as ocular complications. Data from both clinical trials and real-world settings will be included, providing a comprehensive view of the therapy’s safety profile.
In addition to clinical trial data, Alnylam will introduce the design and rationale of a new global observational study known as DemonsTTRate. This long-term study is intended to evaluate the real-world use of vutrisiran in patients with ATTR-CM, capturing data on treatment patterns, outcomes, and safety in routine clinical practice. Observational studies like DemonsTTRate play an important role in complementing clinical trial findings, as they provide insights into how therapies perform outside the controlled environment of randomized studies.
Further analyses from HELIOS-B will explore the consistency of vutrisiran’s efficacy across sexes, addressing an important aspect of personalized medicine. Understanding whether treatment responses differ between male and female patients can inform more tailored therapeutic approaches. Another presentation will examine the burden of comorbidities in patients with ATTR-CM, offering a clearer picture of the complex clinical landscape in which vutrisiran is being used.
The breadth of data being presented underscores Alnylam’s commitment to advancing the understanding of RNAi therapeutics in cardiovascular disease. By addressing multiple dimensions of treatment—including efficacy, safety, pharmacodynamics, and real-world application—the company aims to provide clinicians with the information needed to make informed decisions about patient care.
Vutrisiran, marketed in certain regions under the brand name AMVUTTRA®, has already received regulatory approvals in various indications. In the European Union, it is approved for the treatment of hereditary transthyretin amyloidosis with polyneuropathy (hATTR-PN) in adults at stage 1 or stage 2, as well as for adults with cardiomyopathy associated with either hereditary or wild-type transthyretin amyloidosis. However, availability across different countries depends on local reimbursement decisions and healthcare system policies.
As with any therapeutic intervention, the use of vutrisiran is associated with specific safety considerations. One of the most notable is the reduction in serum vitamin A levels, which necessitates supplementation to prevent deficiency. Patients receiving the therapy are typically advised to take daily vitamin A supplements within a recommended range and to seek ophthalmologic evaluation if they experience symptoms such as night blindness. Other commonly reported adverse reactions include injection site reactions and mild elevations in liver enzymes, such as alkaline phosphatase and alanine transaminase.
The presentations at Heart Failure 2026 are expected to further solidify vutrisiran’s position as a potentially transformative therapy for ATTR-CM. By demonstrating consistent efficacy across diverse patient populations and maintaining a manageable safety profile, the therapy could play a key role in reshaping the treatment landscape for this challenging condition.
In summary, Alnylam’s upcoming data presentations represent an important step in advancing the clinical understanding of RNAi-based therapies in cardiology. Through detailed analyses of the HELIOS-B trial and the introduction of new real-world research initiatives, the company is contributing to a growing body of evidence supporting the use of vutrisiran in patients with ATTR-CM. As the field continues to evolve, such insights will be essential for improving patient outcomes and expanding access to innovative treatments that address the root causes of disease.
About AMVUTTRA® (vutrisiran)
AMVUTTRA® (vutrisiran) is a transthyretin (TTR) silencer that delivers rapid knockdown of TTR at the source to address the underlying cause of transthyretin amyloidosis (ATTR). In a clinical study, AMVUTTRA rapidly knocked down TTR in as early as six weeks and decreased TTR levels by 87% with two and a half years of treatment. It isapproved as a treatment for the polyneuropathy of hereditary transthyretin-mediated amyloidosis (hATTR-PN) in adults and for the cardiomyopathy of wild-type or hereditary transthyretin-mediated amyloidosis (ATTR-CM) in adults in various countries, globally. Administered quarterly via subcutaneous injection, AMVUTTRA is the first and only silencer approved for the treatment of ATTR-CM and hATTR-PN.
About Transthyretin Amyloidosis (ATTR)
Transthyretin amyloidosis (ATTR) is an underdiagnosed, rapidly progressive, debilitating, and fatal disease caused by pathogenic transthyretin (TTR) proteins, which accumulate as amyloid deposits in various parts of the body, including the nerves, heart, and gastrointestinal tract. Patients may present with polyneuropathy, cardiomyopathy, or both manifestations of disease. There are two different forms of ATTR – hereditary ATTR (hATTR), which is caused by a TTR gene variant, and wild-type ATTR (wtATTR), which occurs without a TTR gene variant. It is estimated that more than 500,000 people worldwide live with ATTR.
About RNAi
RNAi (RNA interference) is a natural cellular process of gene silencing that represents one of the most promising and rapidly advancing frontiers in biology and drug development today. Its discovery has been heralded as “a major scientific breakthrough that happens once every decade or so,” and was recognized with the award of the 2006 Nobel Prize for Physiology or Medicine. By harnessing the natural biological process of RNAi occurring in our cells, a new class of medicines known as RNAi therapeutics is now a reality.
Small interfering RNA (siRNA), the molecules that mediate RNAi and comprise Alnylam’s RNAi therapeutic platform, function upstream of today’s medicines by potently silencing messenger RNA (mRNA) – the genetic precursors – that encode for disease-causing or disease pathway proteins, thus preventing them from being made. This is a revolutionary approach with the potential to transform the care of patients with genetic and other diseases.
About Alnylam Pharmaceuticals
Alnylam (Nasdaq: ALNY) is a leading global biopharmaceutical company and the pioneer of the RNA interference (RNAi) revolution. The Company is focused on developing transformative therapies with the potential to prevent, halt, or reverse disease. For more than two decades, Alnylam has advanced the Nobel-Prize-winning science of RNAi, delivering critical breakthroughs and six approved medicines. Alnylam has medicines available in more than 70 countries and a rapidly expanding and robust pipeline, in addition to consistently being recognized as an exceptional workplace and socially responsible organization. The Company is executing on its Alnylam 2030 strategy to accelerate innovation and scale impact to transform human health.
