The COCOA-PAD II Trial

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. Our primary outcome is change in six-minute walk distance at six-month follow-up. Secondary outcomes are Actigraph-measured physical activity, brachial artery flow-mediated dilation (FMD), gastrocnemius muscle biopsy measures of endothelial nitric oxide synthase (eNOS) and phosphorylated eNOS, gastrocnemius muscle perfusion (measured by magnetic resonance imaging (MRI)) and gastrocnemius muscle characteristics (measured by muscle biopsy). To achieve the specific aims, the study will randomize 190 participants age 55 and older with PAD to one of two groups: cocoa flavanols vs placebo. Participants will be followed for six months.

NCT Number	NCT04794530
Lead Sponsor	Northwestern University Collaborators: National Institute on Aging (NIA), University of Minnesota, University of Chicago
Conditions	Peripheral Artery Disease
Enrollment	190 participants
Start Date	2021-11-19
Primary Completion	2026-12-31 (estimated)
Study Completion	2027-06-01 (estimated)
Updated on ClinicalTrials.gov	2026-05-28