What is a clinical trial?

A clinical trial is a research study involving human participants designed to evaluate medical interventions — such as drugs, devices, or behavioral strategies. Trials follow a structured protocol and are registered on ClinicalTrials.gov. They progress through phases: Phase 1 (safety), Phase 2 (efficacy), Phase 3 (large-scale comparison), and Phase 4 (post-market surveillance).

How do I find clinical trials I'm eligible for?

You can search ClinicalTrials.gov or use ClinicalMetric to filter by condition, phase, or location. Each trial listing includes eligibility criteria such as age range, sex, diagnosis, and prior treatment history. Contact the study team directly or ask your physician to refer you to a relevant trial.

Are clinical trials safe to participate in?

Clinical trials are conducted under strict ethical and regulatory oversight, including IRB approval and FDA regulation in the US. All participants must give informed consent after reviewing potential risks and benefits. Phase 1 trials carry more uncertainty, while Phase 3 trials involve interventions with an established safety profile. Participation is always voluntary and you may withdraw at any time.

What are the phases of clinical trials?

Clinical trials progress through four main phases. Phase 1 tests safety and dosing in a small group (20–80 people). Phase 2 evaluates efficacy and side effects in a larger group (100–300). Phase 3 compares the intervention against standard treatments in thousands of participants. Phase 4 occurs after approval and monitors long-term effects in the general population.

Do participants get paid for joining clinical trials?

Many clinical trials offer compensation for time and travel expenses, though payment structures vary widely by study. Compensation is not intended to be coercive. Some trials also cover treatment costs for participants. Always review the consent form carefully and ask the study coordinator about any financial considerations before enrolling.

Heart Disease Clinical Trials 2026: Cardiovascular Studies and Recruiting Research

Medical Notice

This article is for informational purposes only and does not constitute medical advice. Clinical trial eligibility and availability vary. Always consult a qualified healthcare professional before making any medical decisions or considering participation in a clinical trial.

Summary

Cardiovascular disease remains the leading cause of death globally, responsible for approximately 17.9 million deaths per year. In 2026, heart disease clinical trials are advancing on multiple fronts: GLP-1 agonists achieving major cardiovascular event reduction, RNA-silencing therapies achieving durable LDL-C lowering with twice-yearly dosing, gene therapy for inherited cardiomyopathies, and novel approaches to heart failure with preserved ejection fraction (HFpEF) — the form of heart failure with the fewest approved treatments. This guide covers the major trial landscape and how patients can access these studies.

GLP-1 Agonists and Cardiovascular Outcomes

The SELECT trial (semaglutide 2.4mg weekly in patients with established cardiovascular disease but without diabetes) achieved a 20% reduction in major adverse cardiovascular events (MACE) — non-fatal MI, non-fatal stroke, and cardiovascular death — compared to placebo. This landmark result established GLP-1 agonists as a legitimate cardiovascular therapy independent of diabetes and weight loss, and semaglutide 2.4mg received expanded FDA approval for cardiovascular risk reduction in 2024. The SOUL trial (oral semaglutide in T2D with high CV risk) confirmed a 14% MACE reduction with the oral formulation, validating cardiovascular benefit across delivery routes.

Trials now enrolling in 2026 are testing GLP-1 agonist cardiovascular effects in new populations: the FLOW-HF trial is examining semaglutide in heart failure with preserved ejection fraction (HFpEF), while EVOKE-2 is investigating cardiovascular and neurovascular protection in high-risk patients without current GLP-1 indications. Tirzepatide's SURPASS-CVOT cardiovascular outcomes trial (SURMOUNT-5 extension) is fully enrolled and awaiting results.

LDL Lowering: Inclisiran and PCSK9 Inhibitors

Despite the proven benefits of statins, a large proportion of high-risk cardiovascular patients do not achieve guideline-recommended LDL-C targets. PCSK9 inhibitors (evolocumab/Repatha, alirocumab/Praluent) achieve 50–60% additional LDL-C reduction on top of statins but require injections every 2–4 weeks and face cost/adherence barriers. Inclisiran (Leqvio), an RNA interference therapy silencing PCSK9 in hepatocytes, achieves 50% LDL-C reduction with just two injections per year after the initial dose — transforming adherence. The ORION-4 Phase 3 cardiovascular outcomes trial (22,000 patients, primary MACE endpoint) is the pivotal study determining whether inclisiran reduces hard events, with results expected 2026–2027.

Lerodalcib (oral PCSK9 inhibitor, Ionis), zerlasiran (RNA interference PCSK9 inhibitor with quarterly dosing, Silence Therapeutics), and lepodisiran (Eli Lilly Lp(a)-lowering siRNA) represent the expanding portfolio of RNA-targeting cardiovascular therapies. The HORIZON Outcomes trial (pelacarsen, an antisense oligonucleotide targeting Lp(a) in patients with elevated Lp(a) and established ASCVD) and olpasiran OCEAN(a)-OUTCOMES trials are evaluating Lp(a) reduction as a cardiovascular end point for the first time in large randomized trials.

Heart Failure with Preserved Ejection Fraction (HFpEF)

HFpEF — where the heart muscle contracts normally but the ventricles are stiff, impairing filling — accounts for half of all heart failure cases (approximately 3 million US patients) and until recently had no approved disease-modifying treatment. SGLT2 inhibitors empagliflozin and dapagliflozin achieved modest but significant reductions in heart failure hospitalization in Phase 3 HFpEF trials (EMPEROR-Preserved, DELIVER) and are now guideline-recommended. The question in 2026 is whether more potent agents can achieve greater mortality reduction.

The SUMMIT trial (tirzepatide in HFpEF with obesity) showed a 38% reduction in heart failure events and significant improvements in exercise capacity and quality of life, making it one of the most important HFpEF results in years. Finerenone (non-steroidal mineralocorticoid receptor antagonist) is in the FINEARTS-HF Phase 3 with top-line results expected in 2026. Anti-inflammatory approaches — colchicine, IL-1β inhibition (canakinumab) for post-MI inflammatory cardioprotection — and mavacamten (myosin inhibitor for hypertrophic cardiomyopathy, EXPLORER-HCM) are expanding the HFpEF and cardiomyopathy trial portfolios.

Gene Therapy for Inherited Cardiomyopathies

Transthyretin amyloid cardiomyopathy (ATTR-CM) — caused by misfolding of TTR protein — affects an estimated 500,000 Americans, predominantly older adults and those of West African descent (Val122Ile variant). RNA interference therapies eplontersen (NEURO-TTRansform) and vutrisiran (HELIOS-B) have achieved significant reductions in TTR levels and cardiovascular events. Gene editing approaches targeting TTR in hepatocytes using CRISPR base editing (NTLA-2001, Intellia) achieved 90% TTR knockdown with a single treatment in Phase 1/2, with no return of protein after 18+ months — potentially a functional cure for ATTR cardiomyopathy.

For Duchenne cardiomyopathy — the cardiac manifestation of Duchenne muscular dystrophy — exon-skipping and micro-dystrophin gene therapy trials (Sarepta SRP-9001/Elevidys, Solid Biosciences SGT-003) are evaluating cardiac function endpoints alongside motor outcomes. The PRECISION Phase 2 is evaluating AAV-mediated SERCA2a gene therapy for heart failure with reduced ejection fraction — restoring calcium handling to dysfunctional myocytes.

How to Find and Enroll in Cardiovascular Trials

Cardiovascular trials are conducted at cardiology practices, academic medical centers, and community hospitals across the United States. ClinicalTrials.gov searches by condition (e.g., "Heart Failure," "Coronary Artery Disease," "Atrial Fibrillation") filtered to "Recruiting" status reveal hundreds of options. Key eligibility data to have ready: echocardiogram with ejection fraction, recent BNP/NT-proBNP levels, LDL-C levels, eGFR, and a complete list of current cardiac medications. The American Heart Association's Patient Pages and the American College of Cardiology's CardioSmart platform provide patient-facing trial information.

Key Takeaways

SELECT trial confirmed semaglutide 2.4mg reduces MACE by 20% in cardiovascular disease patients without diabetes, establishing GLP-1 agonists as cardiovascular drugs independent of metabolic effects — now expanded in further trials for HFpEF and neurovascular protection.
Inclisiran (ORION-4 outcomes trial enrolling) achieves 50% LDL-C reduction with twice-yearly dosing; Lp(a)-lowering siRNAs (pelacarsen, olpasiran) are in the first large Phase 3 outcomes trials for this high-risk lipid target.
Tirzepatide SUMMIT showed a 38% reduction in HFpEF events in obese patients, providing the strongest evidence yet for a treatment beyond SGLT2 inhibitors in this underserved population.
CRISPR base editing (NTLA-2001) achieved 90% TTR knockdown from a single dose in ATTR-CM Phase 1/2 — potentially a single-treatment cure for transthyretin amyloid cardiomyopathy.
Cardiovascular trials run at community cardiology practices as well as academic centers, making enrollment more geographically accessible than many other trial types.