A Phase 2 interventional study of Exogenous Ketone Drink and Placebo in Heart Failure With Preserved Ejection Fraction (HFPEF), Heart Failure With Normal Ejection Fraction and Heart Failure, Diastolic, sponsored by Duke University. Enrolling by invitation at 1 site in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-10-14.
Sponsored by Duke University · Phase 2, Interventional, and Treatment
The goal of this clinical research study is to test what effects a ketone drink will have in people with heart failure with preserved ejection fraction (HFpEF), including on exercise and heart function. Patients with HFpEF often have difficulty exercising, and our goal is to understand whether a ketone drink changes much patients can exercise. The study has three visits, including a baseline visit to assess for study eligibility, and two visits (one after 8 weeks of a ketone drink or a placebo drink, and another one after 8 weeks of whichever drink the participant did not receive the first time).
199 studies on the registry are indexed under Heart Failure, Diastolic; 44 are open to participants now.
This study's planned enrollment of 20 is below the median of 48 across 139 interventional studies indexed under Heart Failure, Diastolic.
Browse Heart Failure, Diastolic studies →Duke University is the lead sponsor of 2,063 studies on the registry; 273 are open to participants now.
Of its 204 completed or terminated interventional studies of FDA-regulated products, 167 (82%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Evidence for elevated filling pressures as follows (at least one of the following between a-d):
a. Mitral early (E)/mitral septal tissue annular (e') velocity ratio > 8 on echocardiography in addition to one of the following:
i. Enlarged left atrium (LA>4.0 cm width or LA volume index >34 mL/m2)
ii. Chronic loop diuretic use for control of symptoms
iii. Elevated natriuretic peptides within the past year (NT-proBNP>125 pg/ml or BNP>35 pg/ml)
b. Mitral E/e' ratio > 14 at rest or with exercise on echocardiography
c. Elevated invasively-determined filling pressures previously (resting left ventricular end-diastolic pressure >16 mm Hg or pulmonary capillary wedge pressure > 14 mmHg; or PCWP or LVEDP ≥ 25 mmHg with exercise)
d. Prior episode of acute heart failure requiring IV diuretics with evidence of volume overload on exam or radiology, or evidence of elevated natriuretic peptides.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Chronic obstructive pulmonary disease: long-term lung disease that makes it hard to breathe out, including emphysema and chronic bronchitis.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
LVEF (left ventricular ejection fraction)
The share of blood the heart’s main pumping chamber (the left ventricle) pushes out with each beat, measured by an echocardiogram (heart ultrasound) or a MUGA scan. About 50–70% is normal.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
GFR and eGFR (kidney filtering)
GFR (glomerular filtration rate) is how much blood the kidneys filter each minute. It is usually estimated from a blood test — eGFR, by formulas such as CKD-EPI or MDRD — and some studies ask for it to be measured directly instead. Usually given in mL/min/1.73 m².
Check the method, the units and the minimum the study states. A value of 90 or above is in the normal-or-high range, but kidney damage can show in other tests too.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
COPD
Chronic obstructive pulmonary disease: long-term lung disease that makes it hard to breathe out, including emphysema and chronic bronchitis.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
(R)-1,3-butanediol (commercially obtained as "KetoneIQ")
Dietary Supplement: Exogenous Ketone Drink
ketone-free solution
Dietary Supplement: Placebo
Drug pages: Butylene glycol · Butylene Glycols
(R)-1,3-butanediol (BD, commercially available as "KetoneIQ") initially dosed 300 mg/kg BID (target dose 400 mg/kg grams BID if tolerated) for 8 weeks
Also known as: (R)-1,3-butanediol, KetoneIQ, ketone
equi-volume placebo administered for 8 weeks
Maximal exercise capacity
Peak VO2 assessed by cardiopulmonary exercise testing
Time frame: 8 weeks
Respiratory exchange ratio
Respiratory exchange ratio (RER) during cardiopulmonary exercise testing at 25 watts
Time frame: 8 weeks
Vasodilatory reserve
Percent change in total peripheral resistance from rest to peak exercise
Time frame: 8 weeks
Left atrial volume index
Left atrial volume index measured by echocardiogram
Time frame: 8 weeks
Resting E/e'
Resting E/e' on echocardiogram
Time frame: 8 weeks
Heart failure-related health status
Heart failure-related health status using Kansas City Cardiomyopathy Questionnaire overall summary score (KCCQ-OSS). Score range is from 0 to 100, with higher scores indicating better health status and lower scores indicating poorer health status.
Time frame: 8 weeks
NT-proBNP
N-terminal pro-B-type natriuretic peptide levels measured in peripheral blood.
Time frame: 8 weeks
Global longitudinal strain
Global longitudinal strain measured by echocardiogram
Time frame: 8 weeks
Exercise E/e' ratio
Measured during exercise as the ratio of early diastolic transmitral flow velocity (E) to early diastolic mitral annular velocity (e')
Time frame: 8 weeks
Hemoglobin A1c
Hemoglobin A1c level measured in peripheral blood
Time frame: 8 weeks
Fat free mass
Fat free mass measured by body composition scan (DXA)
Time frame: 8 weeks
Pulse wave velocity
Pulse wave velocity measured during arterial tonometry
Time frame: 8 weeks
Ventilatory efficiency
VE/VCO2 slope during cardiopulmonary exercise testing
Time frame: 8 weeks
Plan to share: No
No publications or documents are linked to this record.
Started Jul 2025 (actual). Primary completion is estimated for Jun 2027, 23 months after the start.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.
No contact was published for this record. The registry link below has the sponsor’s details.
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Studies of the drugs tested here: Butylene glycol · Butylene Glycols