Get a proposal

Cardiovascular · Clinical trials

Heart Failure with Preserved EF (HFpEF) 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 preserved ef (hfpef) — and why its trials are hard

Heart failure with preserved ejection fraction (HFpEF) is defined by signs and symptoms of heart failure with a left ventricular ejection fraction of 50% or higher (mildly reduced, 41-49%, is a related category). It accounts for roughly half of all heart failure and is driven by aging, hypertension, obesity, diabetes and atrial fibrillation, producing diastolic dysfunction and elevated filling pressures. For decades HFpEF was defined by therapeutic failure: renin-angiotensin blockers, mineralocorticoid antagonists and neprilysin inhibition all failed or narrowly missed their primary endpoints. The breakthrough came with SGLT2 inhibitors. EMPEROR-Preserved was the first trial to show a clear benefit, with empagliflozin reducing the composite of cardiovascular death or heart-failure hospitalization; DELIVER confirmed the class effect with dapagliflozin. These agents are now guideline-recommended across the ejection-fraction spectrum. Sacubitril/valsartan (PARAGON-HF) narrowly missed statistical significance but earned a broadened FDA indication. GLP-1 receptor agonists (semaglutide, STEP-HFpEF) show promise in obesity-related HFpEF. As the landmark first positive trial, EMPEROR-Preserved with empagliflozin holds precedence in this indication.

Indication
Heart Failure with Preserved EF (HFpEF)
ICD-10-CM
I50.30 — Diastolic (congestive) heart failure

Approved therapies & pivotal evidence

What's been approved — and by how much it moved the endpoint

Drug (brand)ApprovedSettingPivotal trialPrimary endpointMagnitude of benefit
Empagliflozin (Jardiance)2022HFpEF/heart failure across EF spectrumEMPEROR-PreservedComposite of CV death or hospitalization for heart failureHR 0.79 (95% CI 0.69-0.90) vs placebo; benefit driven largely by reduced HF hospitalizations. First positive HFpEF outcome trial
Dapagliflozin (Farxiga)2023HFpEF/heart failure across EF spectrumDELIVERComposite of worsening heart failure or CV deathHR 0.82 (95% CI 0.73-0.92) vs placebo; consistent across EF and confirmed the SGLT2 class effect
Sacubitril/valsartan (Entresto)2021Broadened HF label including below-normal EF (mildly reduced/preserved)PARAGON-HFComposite of total HF hospitalizations and CV deathRR 0.87 (95% CI 0.75-1.01), narrowly missed significance (p=0.06); label expanded based on totality of evidence

Where trials have failed

Drugs that missed their endpoint — and what contributed

The most instructive lessons in heart failure with preserved ef (hfpef) development come from programmes that failed the endpoint that mattered.

Drug / trialEndpoint outcomeWhat contributed
Spironolactone — TOPCATMissed the overall primary composite (CV death, aborted cardiac arrest, HF hospitalization)Marked regional heterogeneity; benefit seen in the Americas but not in Russia/Georgia where drug-adherence and diagnosis were questioned, diluting the overall result
Irbesartan — I-PRESERVENo reduction in death or CV hospitalization in HFpEFARB did not improve outcomes; reinforced that renin-angiotensin blockade alone is ineffective in HFpEF
Candesartan — CHARM-PreservedDid not significantly reduce the primary CV death or HF hospitalization compositeOnly a modest, non-significant effect on hospitalizations; underpowered for a definitive HFpEF benefit
Perindopril — PEP-CHFFailed to show significant long-term benefit on the primary endpointHigh crossover to open-label ACE inhibitors and lower-than-expected event rates undermined power
Vericiguat — VITALITY-HFpEFDid not improve physical limitation (KCCQ) or 6-minute walk distanceSoluble guanylate cyclase stimulation failed to improve symptoms in HFpEF despite benefit in reduced-EF (VICTORIA)

Choosing the right endpoint

Primary endpoints that matter in heart failure with preserved ef (hfpef) trials

  • Composite CV death or HF hospitalization — Primary endpoint in EMPEROR-Preserved and DELIVER; HF hospitalization typically drives the benefit
  • Total (recurrent) HF hospitalizations — Captures repeat events; central to PARAGON-HF analysis
  • KCCQ clinical summary score — Patient-reported health status; primary in symptom trials like VITALITY-HFpEF and STEP-HFpEF
  • 6-minute walk distance — Functional capacity measure used as a co-primary in several HFpEF symptom studies

How iNGENū runs heart failure with preserved ef (hfpef) 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.

Planning a heart failure with preserved ef (hfpef) trial?
Request a fixed-milestone proposal and a tailored endpoint & feasibility summary for this indication.
Request a proposal

Frequently asked questions

Heart Failure with Preserved EF (HFpEF) clinical trials — FAQs

Which drug class finally worked in HFpEF?
SGLT2 inhibitors. EMPEROR-Preserved (empagliflozin) was the first trial to show a clear reduction in cardiovascular death or heart-failure hospitalization, confirmed by DELIVER (dapagliflozin).
Why is TOPCAT controversial?
The overall trial was neutral, but post-hoc regional analysis showed benefit in the Americas and none in Russia/Georgia, where concerns about drug adherence and diagnosis suggested the neutral result was misleading.
Did Entresto succeed in HFpEF?
PARAGON-HF narrowly missed statistical significance (p=0.06), but the totality of data supported a broadened FDA indication covering patients with below-normal ejection fraction.

Ready to discuss your heart failure with preserved ef (hfpef) trial?

Talk to our physician-led team about an FDA-ready, cost-efficient trial design.

Request a proposal