NCT04794530 · Northwestern University
The COCOA-PAD II Trial
(COCOA-PAD II)
What this study is about
Among people with peripheral artery disease (PAD) age 55 and older, the investigators will test the hypothesis that PAD participants randomly assigned to cocoa flavanols will have greater improvement or less decline in six-minute walk distance at six-month follow-up, compared to those randomly assigned to placebo.
View original scientific description
Among people with peripheral artery disease (PAD) age 55 and older, the investigators will test the hypothesis that PAD participants randomized to cocoa flavanols 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 190 participants with PAD age 55 and older to one of two groups for six months: cocoa flavanols vs placebo.
Interventions
DRUG
cocoa flavanols
The cocoa flavanols intervention is manufactured by Mars Inc. Participants randomized to cocoa flavanols will take two capsules daily of cocoa flavanols. The two capsules of cocoa flavanols will contain approximately 500 mg of cocoa flavanols and appoximately 80 mg of (-)-epicatechin.
DRUG
placebo
The placebo intervention will be manufactured by Mars Inc. and will appear identical to the cocoa flavanols intervention. Participants will take two capsules daily of placebo. The placebo will be a cellulose based capsule and will not contain cocoa flavanols or (-)-epicatechin.
Primary outcome measures
Six-month change in six-minute walk distance
Time frame: Baseline to six-month follow-up
Change in six-minute walk distance at six-month follow-up will be compared between those randomized to cocoa flavanols vs. those randomized to placebo.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Age 55 and older 2. Presence of peripheral artery disease (PAD). PAD will be defined as either: 1. An ABI \<= 0.90 at baseline. 2. 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. 3. An ABI of \>0.90 and \<=1.00 who experience a a 20% or greater drop in ABI in either leg after the heel-rise test will also be included.
Exclusion criteria
- Above- or below-knee amputation 2. Critical limb ischemia 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 one-week study run-in 7. Planned major surgery, coronary or leg revascularization during the next eight months 8. Major surgery, coronary or leg revascularization or major cardiovascula
Where
- Chicago, Illinois
- Minneapolis, Minnesota
Collaborators
National Institute on Aging (NIA), University of Minnesota, University of Chicago
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 28, 2026 · Source of record for eligibility and locations