Peripheral Artery Disease (PAD)Phase 3NICENCT07782671
The NICE-PAD II Trial
A Phase 3 study testing Nicotinamide Riboside (NR) in people with Peripheral Artery Disease (PAD), run by Northwestern University.
Trial summary
Among people with peripheral artery disease (PAD) age 50 and older, the investigators will test the hypothesis that PAD participants randomized to nicotinamide riboside (NR) will have greater improvement or less decline in six-minute walk distance at six-month follow-up, compared to those randomized to placebo. Read more about this study
- Who is it for?
- Ages 50 years and older
- Conditions the study is for
- Peripheral Artery Disease (PAD)
- What is being tested?
- Nicotinamide Riboside (NR)
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 250 participants
- Where
- No sites listed yet
- Study dates
- Dec 2026to Jul 2031
- Phase
- Phase 3
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 50 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- 1. Age 50 and older.
- 2. Presence of peripheral artery disease (PAD). PAD will be defined as either: a. An ABI < 0.90 at baseline. b. Vascular lab evidence of PAD (such as a toe brachial pressure < 0.70 or an ankle brachial index less than or equal to 0.90), or angiographic evidence of PAD defined as at least 70% stenosis of an artery supplying the lower extremities. c. An ABI of >0.90 and <1.00 who experience a 20% or greater drop in ABI in either leg after the heel-rise test.
Who cannot join
- 1. Above- or below-knee amputation
- 2. Critical limb ischemia defined as an ABI <0.40 with symptoms of rest pain
- 3. Wheelchair confinement or requiring a walker to ambulate
- 4. Walking is limited by a symptom other than PAD
- 5. Current foot ulcer on bottom of foot
- 6. Failure to successfully complete the study run-in
Show all 18Show fewer
- 7. Planned major surgery, coronary or leg revascularization during the next six months
- 8. Major surgery, coronary or leg revascularization, or major cardiovascular event in the previous three months
- 9. Major medical illness including lung disease requiring oxygen, Parkinson's disease, a life-threatening illness with life expectancy less than six months, or cancer requiring treatment in the previous two years. [NOTE: potential participants may still qualify if they have had treatment for an early stage cancer in the past two years and the prognosis is excellent. Participants who require oxygen only at night may still qualify.]
- 10. Non-English speaking. The integrity of the clinical trial requires clear and effective communication for data collection and study interventions. The trial does not have sufficient staff members who are fluent in non-English languages, nor does it have the budget to translate all study materials into other languages.
- 11. Current participation in or completion of a clinical trial intervention in the previous three months. However, at investigator discretion, depending on the nature of the trial, when the intervention was administered, or whether the participant remains in long term follow-up, a potential participant formally enrolled in a clinical trial may be eligible.
- 12. Visual impairment that limits walking ability.
- 13. Participation in a supervised treadmill exercise program or in a cardiac rehabilitation program in the previous three months or who plan to begin a supervised treadmill exercise program or a cardiac rehabilitation program in the next six months.
- 14. Unstable angina.
- 15. Unwilling to participate in study intervention.
- 16. Allergy to nicotinamide riboside.
- 17. Potential participants who have taken a daily dose of 100 mg or more of nicotinamide riboside or niacin, 200 mg or more of vitamin B3, or nicotinamide mononucleotide (NMN) in the previous three months.
- 18. In addition to the above criteria, investigator discretion will be used to determine if the trial is unsafe or not a good fit for the potential participant.
Trial locations and contacts
No sites are listed yet. Contact the study team or a site near you to ask about taking part.
About this study
Official title: Nicotinamide Riboside to Improve Functioning in PAD
Among people with peripheral artery disease (PAD) age 50 and older, the investigators will test the hypothesis that PAD participants randomized to nicotinamide riboside (NR) will have greater improvement or less decline in six-minute walk distance at six-month follow-up, compared to those randomized to placebo. The study will randomize 250 participants with PAD age 50 and older to one of two groups for six months: nicotinamide riboside vs placebo. Our primary outcome is change in six-minute walk distance at six-month follow-up. Secondary outcomes are Walking Impairment Questionnaire (WIQ) distance score, PROMIS Mobility score, calf muscle perfusion (measured by magnetic resonance arterial spin labeling (MRI ASL)), oxidative stress (measured by plasma oxidized LDL), NAD+ abundance in whole blood, 6-minute walk improvement by baseline whole blood NAD+ levels, and 6-minute walk distance at 4 weeks after intervention completion.
To achieve the specific aims, the study will randomize 250 participants age 50 and older with PAD to one of two groups: nicotinamide riboside vs placebo. Participants will be followed for six months, with an additional four-week follow-up period after completion of the study intervention.
- Conditions
- Peripheral Artery Disease (PAD)
- Being tested
- Nicotinamide Riboside (NR), Placebo
- Keywords
- nicotinamide riboside, NICE, PAD, peripheral arterial disease, Intermittent claudication, Peripheral vascular disease
- Medical subject headings
- Peripheral Arterial Disease, Intermittent Claudication, Peripheral Vascular Diseases
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Nicotinamide Riboside (NR)Drug
The nicotinamide riboside intervention is manufactured by ChromaDex. Participants randomized to nicotinamide riboside will take two capsules twice daily. Each capsule contains 250 mg of nicotinamide riboside, for a total of 1000 mg of nicotinamide riboside per day.
PlaceboDrug
The placebo is manufactured by ChromaDex and is visually identical to the nicotinamide riboside capsules. Participants randomized to placebo will take two capsules twice daily. The placebo will not contain any nicotinamide riboside.
| Study group | Role | What they receive |
|---|---|---|
| Nicotinamide riboside (NR) | Active comparator | Not described Receives: Drug: Nicotinamide Riboside (NR) |
| Placebo | Placebo comparator | Not described Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Six-minute walk distance
Change in six-minute walk distance between baseline and 6-month follow-up.
Measured: Baseline to 6-months
Secondary outcomes (6)
Walking Impairment Questionnaire (WIQ) distance score
Patient reported outcome measuring assessing participant perceived ability to walk distances. Scored on a 0-100 scale, 100-best.
Measured: Baseline to 6-month follow-up
PROMIS Mobility score.
Patient reported outcome measure of mobility.
Measured: Baseline to 6-month follow-up
Calf muscle perfusion
Calf muscle perfusion measured by magnetic resonance imaging (MRI) arterial spin labeling.
Measured: Baseline to 6-month follow-up
Oxidative stress
Measured by plasma oxidized LDL.
Measured: Baseline to 6-month follow-up
NAD+
NAD+ will be measured in whole blood
Measured: Baseline to 6-month follow-up
6-minute walk
Distance walked in 6- minutes
Measured: Baseline to four weeks after primary outcome measurement (i.e. 7-month follow-up)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted24 Aug 2026
- Study startDec 2026 (estimated)
- Primary completionDec 2030 (estimated)
- Study completionJul 2031 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Peripheral Artery Disease (PAD)Studies of the same condition, open and under way.
- More trials run by Northwestern UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 3
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 250 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Northwestern University
- Sponsor type
- University, hospital or other
- Collaborators
- National Institute on Aging (NIA), University of Chicago, University of Minnesota
- Responsible party
- Principal investigator, Mary McDermott, Northwestern University
- Investigators
- Mary McDermott, Principal investigator, Northwestern University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07782671
- Sponsor's protocol ID
- STU00225372
- Other IDs
- 1R01AG090846
- Acronym
- NICE
- Status last verified
- Aug 2026
- First submitted
- 19 Aug 2026
- Last updated
- 24 Aug 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 24 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Nicotinamide Riboside to Improve Functioning in PAD
- ClinicalTrials.gov ID
- NCT07782671
- Acronym / sponsor ID
- NICE / STU00225372
- Conditions
- Peripheral Artery Disease (PAD)
- Keywords
- nicotinamide riboside, NICE, PAD, peripheral arterial disease, Intermittent claudication, Peripheral vascular disease
- Phase
- Phase 3
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 250 participants (estimated)
- Lead sponsor
- Northwestern UniversityUniversity, hospital or other
- Collaborators
- National Institute on Aging (NIA), University of Chicago, University of Minnesota
- Study start
- Dec 2026 (estimated)
- Primary completion
- Dec 2030 (estimated)
- Study completion
- Jul 2031 (estimated)
- First posted
- 24 Aug 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Among people with peripheral artery disease (PAD) age 50 and older, the investigators will test the hypothesis that PAD participants randomized to nicotinamide riboside (NR) will have greater improvement or less decline in six-minute walk distance at six-month follow-up, compared to those randomized to placebo. The study will randomize 250 participants with PAD age 50 and older to one of two groups for six months: nicotinamide riboside vs placebo. Our primary outcome is change in six-minute walk distance at six-month follow-up. Secondary outcomes are Walking Impairment Questionnaire (WIQ) distance score, PROMIS Mobility score, calf muscle perfusion (measured by magnetic resonance arterial spin labeling (MRI ASL)), oxidative stress (measured by plasma oxidized LDL), NAD+ abundance in whole blood, 6-minute walk improvement by baseline whole blood NAD+ levels, and 6-minute walk distance at 4 weeks after intervention completion.
To achieve the specific aims, the study will randomize 250 participants age 50 and older with PAD to one of two groups: nicotinamide riboside vs placebo. Participants will be followed for six months, with an additional four-week follow-up period after completion of the study intervention.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Quadruple blind (participant, care provider, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Nicotinamide riboside (NR) | Active comparator | Drug: Nicotinamide Riboside (NR) |
| Placebo | Placebo comparator | Drug: Placebo |
Who may qualify
- Ages
- 50 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- 1. Age 50 and older.
- 2. Presence of peripheral artery disease (PAD). PAD will be defined as either: a. An ABI < 0.90 at baseline. b. Vascular lab evidence of PAD (such as a toe brachial pressure < 0.70 or an ankle brachial index less than or equal to 0.90), or angiographic evidence of PAD defined as at least 70% stenosis of an artery supplying the lower extremities. c. An ABI of >0.90 and <1.00 who experience a 20% or greater drop in ABI in either leg after the heel-rise test.
Key exclusion criteria (18 listed)
- 1. Above- or below-knee amputation
- 2. Critical limb ischemia defined as an ABI <0.40 with symptoms of rest pain
- 3. Wheelchair confinement or requiring a walker to ambulate
- 4. Walking is limited by a symptom other than PAD
- 5. Current foot ulcer on bottom of foot
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Nicotinamide Riboside (NR)The nicotinamide riboside intervention is manufactured by ChromaDex. Participants randomized to nicotinamide riboside will take two capsules twice daily. Each capsule contains 250 mg of nicotinamide riboside, for a total of 1000 mg of nicotinamide riboside per day. | Drug | Nicotinamide riboside (NR) |
| PlaceboThe placebo is manufactured by ChromaDex and is visually identical to the nicotinamide riboside capsules. Participants randomized to placebo will take two capsules twice daily. The placebo will not contain any nicotinamide riboside. | Drug | Placebo |
Primary outcome
Six-minute walk distance
Time frame: Baseline to 6-months
Change in six-minute walk distance between baseline and 6-month follow-up.
6 secondary outcomes
Walking Impairment Questionnaire (WIQ) distance score
Time frame: Baseline to 6-month follow-up
PROMIS Mobility score.
Time frame: Baseline to 6-month follow-up
Calf muscle perfusion
Time frame: Baseline to 6-month follow-up
Oxidative stress
Time frame: Baseline to 6-month follow-up
NAD+
Time frame: Baseline to 6-month follow-up
6-minute walk
Time frame: Baseline to four weeks after primary outcome measurement (i.e. 7-month follow-up)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 24 Aug 2026.
Related trials for Peripheral Artery Disease (PAD)
Active, not recruiting
Preventing Kidney Injury Using Carbon Dioxide as Contrast Medium in Patients With Peripheral Arterial Disease (PAD) and Chronic Kidney Disease (CKD) Having Arterial Intervention
Peripheral Arterial Disease, Chronic Kidney Diseases
Recruiting
Radiotracer-Based Perfusion Imaging of Patients With Peripheral Arterial Disease
Peripheral Artery Disease, Diabetes Mellitus
RecruitingPhase 4
Ramipril Treatment of Claudication: Oxidative Damage and Muscle Fibrosis
Peripheral Arterial Disease
RecruitingPhase 3
Reducing Adverse Vascular Outcomes With Factor XI Inhibition in Adult Participants With Peripheral Artery Disease
Peripheral Artery Disease (PAD)
Active, not recruiting
IV-X Medical First-in-Human Peripheral Intravascular Lithotripsy Study for PAD
Peripheral Artery Disease
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Mary McDermott principal investigator
Northwestern University
Questions about this trial
What is this clinical trial studying?
A Phase 3 study testing Nicotinamide Riboside (NR) in people with Peripheral Artery Disease (PAD), run by Northwestern University.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 18 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 24 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Mary McDermott, MD (3125036419, mdm608@northwestern.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Six-minute walk distance (time frame: Baseline to 6-months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 24 Aug 2026.