Skip to content

Inorganic NItrate and EXercise Performance in Heart Failure (iNIX-HF): Dose Response

Inorganic NItrate and EXercise Performance in Heart Failure (iNIX-HF): Dose Response

Status
Completed
Phases
Phase 1Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02797184
Enrollment
42
Registered
2016-06-13
Start date
2017-10-31
Completion date
2021-12-15
Last updated
2025-05-20

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Heart Failure

Brief summary

The purpose of this study is to do the work that is necessary and sufficient for setting up an appropriate multi-center, randomized clinical trial (RCT) of a new therapy for heart failure: inorganic nitrate. The investigators will first determine the effects and palatability of \ 12.8mmol KNO3 (an oral pill) as compared to the roughly equivalent amount of nitrate in 2 beetroot juice (BRJ) Sports Shots (by James White Drinks). Next, the investigators will determine the effects of inorganic nitrate (KNO3 in an oral pill format) on blood pressure, blood nitrate levels, breath nitric oxide (NO) levels, and exercise performance in a dose-response study. Third, the investigators will perform a small phase II chronic treatment study that will allow them to determine the best primary endpoint and the numbers of patients the investigators will need to study in the large, multi-center RCT to follow this project. In the small study and in the RCT to follow, the investigators will determine whether inorganic nitrate can improve aerobic exercise capacity, muscle power, and speed of muscle contraction, and lessen the effort of breathing during exercise.

Detailed description

1. Subjects will be patients with Heart Failure (HF). 2. All subjects will be consented. 3. All subjects will give permission for the investigators to review their medical records. 4. After consenting to participate, subjects will be instructed to refrain from spitting or the use of an antibacterial mouthwash, antacids, proton pump inhibitors, or chewing gum during the morning of each clinic visit. 5. Subjects will have a physical examination. 6. Subjects will undergo transthoracic echocardiographic imaging at rest (unless they had this performed within the past 6 months). 7. Subjects will be asked to undergo a mouth swab for bacterial DNA analyses. 8. Subjects will be asked to answer questionnaires regarding their medical health (basic health questionnaire, Minnesota living with heart failure questionnaire, a combined fatigue questionnaire. 9. Dose visit 1: Subjects will receive 2 capsules containing either 10 or 20 mmol of potassium nitrate (KNO3). 10. Before and at 3 hourly time points after receiving the KNO3, subjects will undergo phlebotomy for plasma nitrite levels, will have their blood pressure measured, and will blow into a small machine to assess the amount of nitric oxide in their breath. 11. Exercise Test 1: Subjects will complete measurements of leg muscle power by doing knee extension exercises on a dynamometer (a device that measures voluntary muscle force production while controlling the speed of movement). 12. Exercise Test 2: Subjects complete a measurement of peak aerobic capacity (VO2peak) while walking on a treadmill and breathing into a mouthpiece. Blood pressure, heart rate and heart rhythm will be monitored during this test. 13. Subjects will undergo a 7 d washout period. 14. Dose visit 2: Subjects will receive 2 capsules containing either 10 or 20 mmol of KNO3 (whichever dose they did not receive at dose visit 1). They will repeat the same assessments listed above in 10, 11, and 12.

Interventions

DRUGKNO3, potassium nitrate

Potassium nitrate (KNO3) will be given orally in 2 gelatin capsules, which will be compounded by the Barnes-Jewish Hospital Pharmacy. The doses are 10 mmol and 20 mmol KNO3.

Sponsors

Washington University School of Medicine
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)

Masking description

Both the participant and the investigator will be masked to which KNO3 dose is administered at each visit. However, it is known at the outset that each patient will receive 10 mmol KNO3 during one visit and 20 mmol KNO3 at another visit, with the order randomly assigned.

Intervention model description

Subjects will receive one drug dose on the first dose visit and the second drug dose on the second dose visit. The order of the two drug doses (10 and 20 mmol KNO3) will be randomized, so that some subjects will receive the lower dose first and others will receive the higher dose first

Eligibility

Sex/Gender
ALL
Age
18 Years to 74 Years
Healthy volunteers
No

Inclusion criteria

1. Sex: females and males 2. Age: at least 18 years and less than 75 years 3. Diagnosis of heart failure with reduced ejection fraction (NYHA II-IV) 4. Ejection fraction \<45% as determined on an imaging study within 12 mo of enrollment 5. Stable medical therapy - defined by no addition or removal (or change of more than 100%) of the following: beta-adrenergic blockade, angiotensin converting enzyme (ACE) inhibitors, or angiotensin receptor blocker (ARB or aldosterone antagonists) for 30 days prior to enrolment

Exclusion criteria

1. Vulnerable populations as defined by the U.S. Department of Health and Human Services, such as prisoners and children 2. Pharmacologic, organic nitrate therapy within the last 3 months 3. Major orthopedic, psychiatric, neurological, or other conditions that would impair performance of the exercise tests in this study 4. Atrial fibrillation/flutter 5. Estimated glomerular filtration rate \< 50 ml/min on most recent clinical laboratories 6. Systolic blood pressure \< 95 mmHg or \>180 mmHg at consent 7. Diastolic blood pressure \<40 mmHg or \>100 mmHg at consent 8. Previous adverse reaction to nitrates necessitating withdrawal of therapy 9. Treatment with phosphodiesterase inhibitors within the last 3 months (patient must also be willing to not take them for the duration of the trial). 10. Ejection fraction \> 45% 11. Primary hypertrophic cardiomyopathy 12. Infiltrative cardiomyopathy (e.g., amyloid) 13. Active myocarditis 14. Complex congenital heart disease 15. Active collagen vascular disease 16. Active angina/ischemia from epicardial coronary disease 17. Percutaneous coronary intervention, new bi-ventricular pacing, or coronary artery bypass grafting within the past 3 months 18. More than mild mitral or aortic stenosis 19. Valvular heart disease with severe regurgitation of any valve. 20. Acute or chronic severe liver disease as evidenced by encephalopathy, international normalized ratio (INR) \>1.7 without anticoagulation therapy, or variceal bleeding 21. Patients requiring exogenous oxygen at rest or for exercise 22. Terminal disease (other than heart failure) with expected survival \< 1 y 23. Enrollment in another therapeutic trial during the period of the study 24. Pregnancy

Design outcomes

Primary

MeasureTime frameDescription
VO2peakacute - 2.5 hours post dosepeak oxygen consumption during treadmill exercise

Secondary

MeasureTime frameDescription
Peak Muscle Poweracute - 2 hours post doseParticipants completed measurements of leg muscle power by doing knee extension exercises on a dynamometer (a device that measures voluntary muscle force production while controlling the speed of movement).
Blood Nitrite Levelstime 0 (before receiving the KNO3 dose) and hourly after receiving KNO3 (1, 2, and 3 hours post-dose)concentrations of nitrite in the blood
Breath Nitric Oxide (NO) Leveltime 0 (before receiving the KNO3 dose) and hourly after receiving KNO3 (1, 2, and 3 hours post-dose)Breath nitric oxide (NO) level will be taken via NIOX breath analyzer

Countries

United States

Participant flow

Participants by arm

ArmCount
All Study Participants
Intervention: Subjects with heart failure will receive a single oral dose of potassium nitrate (10 or 20 mmol KNO3) in 2 gelatin capsules during dose visit 1 and the other dose (10 or 20 mmol KNO3) during dose visit 2. The dose order will be randomized. KNO3, potassium nitrate: Potassium nitrate (KNO3) will be given orally in 2 gelatin capsules, which will be compounded by the Barnes-Jewish Hospital Pharmacy. The doses are 10 mmol and 20 mmol KNO3.
6
Total6

Withdrawals & dropouts

PeriodReasonFG000FG001
Overall StudyStudy was put on hold due to COVID-19. Could not finish these subjects before funding ran out.1818

Baseline characteristics

CharacteristicAll Study Participants
Age, Categorical
<=18 years
0 Participants
Age, Categorical
>=65 years
1 Participants
Age, Categorical
Between 18 and 65 years
5 Participants
Age, Continuous49.3 years
STANDARD_DEVIATION 11.5
Ethnicity (NIH/OMB)
Hispanic or Latino
1 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
5 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
0 Participants
Race (NIH/OMB)
Black or African American
2 Participants
Race (NIH/OMB)
More than one race
0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants
Race (NIH/OMB)
White
4 Participants
Region of Enrollment
United States
6 participants
Sex: Female, Male
Female
1 Participants
Sex: Female, Male
Male
5 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
0 / 60 / 6
other
Total, other adverse events
0 / 60 / 6
serious
Total, serious adverse events
0 / 60 / 6

Outcome results

Primary

VO2peak

peak oxygen consumption during treadmill exercise

Time frame: acute - 2.5 hours post dose

ArmMeasureValue (MEAN)Dispersion
10mmol KNO3VO2peak17.7 mL/kg/minStandard Deviation 3.4
20mmol KNO3VO2peak18.0 mL/kg/minStandard Deviation 4.1
Secondary

Blood Nitrite Levels

concentrations of nitrite in the blood

Time frame: time 0 (before receiving the KNO3 dose) and hourly after receiving KNO3 (1, 2, and 3 hours post-dose)

ArmMeasureGroupValue (MEAN)Dispersion
10mmol KNO3Blood Nitrite Levels0 hr0.489 micro MStandard Deviation 0.295
10mmol KNO3Blood Nitrite Levels1 hr post-ingestion KNO30.568 micro MStandard Deviation 0.244
10mmol KNO3Blood Nitrite Levels2 hr post-ingestion KNO30.658 micro MStandard Deviation 0.277
10mmol KNO3Blood Nitrite Levels3 hr post-ingestion KNO30.646 micro MStandard Deviation 0.261
20mmol KNO3Blood Nitrite Levels3 hr post-ingestion KNO30.769 micro MStandard Deviation 0.529
20mmol KNO3Blood Nitrite Levels0 hr0.432 micro MStandard Deviation 0.258
20mmol KNO3Blood Nitrite Levels2 hr post-ingestion KNO30.864 micro MStandard Deviation 0.916
20mmol KNO3Blood Nitrite Levels1 hr post-ingestion KNO30.591 micro MStandard Deviation 0.481
Secondary

Breath Nitric Oxide (NO) Level

Breath nitric oxide (NO) level will be taken via NIOX breath analyzer

Time frame: time 0 (before receiving the KNO3 dose) and hourly after receiving KNO3 (1, 2, and 3 hours post-dose)

ArmMeasureGroupValue (MEAN)Dispersion
10mmol KNO3Breath Nitric Oxide (NO) Level2 hr28 ppbStandard Deviation 9
10mmol KNO3Breath Nitric Oxide (NO) Level0 hr26 ppbStandard Deviation 13
10mmol KNO3Breath Nitric Oxide (NO) Level3 hr32 ppbStandard Deviation 7
10mmol KNO3Breath Nitric Oxide (NO) Level1 hr28 ppbStandard Deviation 11
20mmol KNO3Breath Nitric Oxide (NO) Level3 hr43 ppbStandard Deviation 16
20mmol KNO3Breath Nitric Oxide (NO) Level1 hr30 ppbStandard Deviation 14
20mmol KNO3Breath Nitric Oxide (NO) Level2 hr36 ppbStandard Deviation 21
20mmol KNO3Breath Nitric Oxide (NO) Level0 hr23 ppbStandard Deviation 9
Secondary

Peak Muscle Power

Participants completed measurements of leg muscle power by doing knee extension exercises on a dynamometer (a device that measures voluntary muscle force production while controlling the speed of movement).

Time frame: acute - 2 hours post dose

ArmMeasureValue (MEAN)Dispersion
10mmol KNO3Peak Muscle Power469.4 Watts/kgStandard Deviation 188.8
20mmol KNO3Peak Muscle Power497.9 Watts/kgStandard Deviation 173.8

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026