HEART FAILURE (HFrEF) · White paper
Heart Failure with Reduced Ejection Fraction (HFrEF) Clinical Trials
Approved therapies, the pivotal-trial endpoints they were judged on, the magnitude of benefit — and the drugs that failed their endpoints, and why.
Indication overview
About heart failure with reduced ejection fraction (hfref) — and why its trials are hard
HFrEF is defined by a left ventricular ejection fraction of 40% or less with impaired systolic function, ventricular dilatation, neurohormonal activation, and exercise intolerance. It affects roughly half of the estimated 23 million people with heart failure worldwide, and despite major therapeutic advances, morbidity, hospitalization, and mortality remain high. Guideline-directed medical therapy now rests on four pillars: ARNI (sacubitril/valsartan) or ACE inhibitors/ARBs, evidence-based beta-blockers, mineralocorticoid receptor antagonists, and SGLT2 inhibitors, with ivabradine and vericiguat as adjuncts in selected patients. Pivotal trials are powered on hard outcomes, principally cardiovascular death and heart-failure hospitalization, often as a composite, which demand large samples and long follow-up. Because background therapy is already highly effective, new agents must show incremental benefit on top of optimized regimens, a central development challenge. Enrichment strategies, biomarkers such as NT-proBNP, quality-of-life instruments, and adaptive designs are increasingly used to demonstrate meaningful benefit efficiently while managing safety signals like hypotension, hyperkalemia, and renal dysfunction.
Approved therapies & pivotal evidence
What's been approved — and by how much it moved the endpoint
| Drug (brand) | Approved | Setting | Pivotal trial | Primary endpoint | Magnitude of benefit |
|---|---|---|---|---|---|
| Sacubitril/valsartan (Entresto) | 2015 | Chronic HFrEF, replacing ACE inhibitor/ARB (ARNI) | PARADIGM-HF (NCT01035255) | Composite of cardiovascular death or HF hospitalization | 20% relative risk reduction (HR 0.80); cardiovascular death also reduced (HR 0.80) |
| Dapagliflozin (Farxiga) | 2020 | HFrEF, with or without type 2 diabetes (SGLT2 inhibitor) | DAPA-HF (NCT03036124) | Composite of worsening HF or cardiovascular death | 26% relative risk reduction (HR 0.74) |
| Empagliflozin (Jardiance) | 2021 | HFrEF (SGLT2 inhibitor) | EMPEROR-Reduced (NCT03057977) | Composite of cardiovascular death or HF hospitalization | 25% relative risk reduction (HR 0.75) |
| Carvedilol (Coreg) | 1997 | Chronic HFrEF (beta-blocker); HF indication | COPERNICUS (severe HF) | All-cause mortality | ~35% relative reduction in mortality vs placebo |
| Spironolactone (Aldactone) | 1985 | Symptomatic severe HFrEF (mineralocorticoid receptor antagonist) | RALES | All-cause mortality | ~30% relative reduction in mortality |
| Vericiguat (Verquvo) | 2021 | High-risk HFrEF after a worsening HF event (sGC stimulator) | VICTORIA (NCT02861534) | Composite of cardiovascular death or HF hospitalization | 10% relative risk reduction (HR 0.90) |
Where trials have failed
Drugs that missed their endpoint — and what contributed
The most instructive lessons in heart failure with reduced ejection fraction (hfref) development come from programmes that failed the endpoint that mattered.
| Drug / trial | Endpoint outcome | What contributed |
|---|---|---|
| Omecamtiv mecarbil (cardiac myosin activator) — GALACTIC-HF (NCT02929329) | Met composite primary endpoint only modestly and did not reduce cardiovascular death; FDA declined approval (Complete Response Letter) | Small absolute benefit driven by HF events, no mortality signal, narrow therapeutic window |
| Ularitide (natriuretic peptide) — TRUE-AHF (NCT01661634) | Improved short-term hemodynamics but no reduction in long-term cardiovascular mortality | Transient vasodilatory effect did not translate into durable outcome benefit |
| Serelaxin (recombinant relaxin-2) — RELAX-AHF-2 (NCT02235077) | Failed to reduce cardiovascular death or worsening heart failure | Acute hemodynamic improvement did not improve hard outcomes |
Choosing the right endpoint
Primary endpoints that matter in heart failure with reduced ejection fraction (hfref) trials
- All-cause mortality — Definitive survival endpoint but requires large samples and long follow-up
- Cardiovascular death — Core component of pivotal composite endpoints in HFrEF
- Heart-failure hospitalization — Frequent, patient-relevant event; often combined with CV death as primary composite
- Left ventricular ejection fraction / reverse remodeling — Mechanistic/imaging measure of cardiac function
- Quality of life (KCCQ) and NT-proBNP — Patient-reported status and biomarker supporting efficacy and enrichment
How iNGENū runs heart failure with reduced ejection fraction (hfref) trials
Physician-led design, built for FDA submission
Endpoint & biomarker strategy
Board-certified specialists design endpoints and patient selection aligned to current FDA guidance for this indication.
FDA-ready data
Built to ICH-GCP and 21 CFR 312.120, with direct FDA submission — data accepted by the FDA, EMA and MHRA.
Faster, lower-cost delivery
~4-week ethics via the TGA CTN scheme, up to 43.5% R&D rebate, and 80–90% below US CRO cost.
The full white paper: approved-product analyses, pivotal endpoints and trial-design strategy. Open-access · no sign-in.
Frequently asked questions
Heart Failure with Reduced Ejection Fraction (HFrEF) clinical trials — FAQs
What are the four pillars of HFrEF therapy?
What is the standard primary endpoint in HFrEF trials?
Why did omecamtiv mecarbil fail to gain approval?
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