Non-invasive therapeutic ultrasound device for treatment of peripheral arterial disease in elderly population - PROJECT SUMMARY Peripheral arterial disease (PAD) is a highly prevalent condition that is growing rapidly due to shifting demographics, affecting 202M people worldwide and 18M in the USA, with an annual growth rate of 6.8%. PAD disproportionally affects the elderly. The highest prevalence of PAD has been observed among older adults: 22.7% among individuals ≥80 years of age versus 1.6% among those 40–49 years of age. Early stages of PAD result in claudication, while the advanced stage of PAD results in resting pain, skin ulcers, gangrene and amputation, all of which reduce mobility, function and independence of seniors. Advances in catheter- based therapies including angioplasty, stenting, and drug-coated balloons, as well as surgical bypass treatments, are often ineffective in PAD and associated with complications and up to 40% rate of long-term restenosis. Acoustic energy modalities such as therapeutic ultrasound (TUS) have been shown to promote collateral vessel growth, angiogenesis, and to improve perfusion in animal models of coronary artery disease and PAD, with promising early human data in both disease processes. Vibrato Medical has developed a novel treatment with the first wearable therapeutic ultrasound (TUS) device for the non-invasive, outpatient treatment of PAD that will promote collateral vessel growth and angiogenesis, restore perfusion and reduce amputation rates. We have already demonstrated VibratoSleeve’s efficacy in markedly improving lower extremity perfusion in healthy volunteers using multiple perfusion measures. The goal of this Fast Track SBIR proposal is to conduct a prospective open-label clinical trial (Phase I) followed by randomized sham-controlled study (Phase II) designed to evaluate the improvement in perfusion and functional outcomes of PAD patients over 65 years of age. A total of 12 subjects will receive wearable VibratoSleeve acute treatment to the posterior calf for 90 minutes at 3 separate clinic visits and 36 patients will receive chronic treatment for 30 sessions of 90 minutes each over 45-day period and will be followed up for another 45 days post-treatment. Efficacy will be assessed by comparing baseline and on-therapy peak walking time on a standard graded treadmill test (primary endpoint), distal lower extremity perfusion rate and tissue oxygenation and hemoglobin as well as ankle- and toe-brachial indices. We will also systematically obtain patient feedback on ease of use, tolerability, and comfort of VibratoSleeve using a standardized questionnaire. Data on the tactile sensation and comfort will inform optimal acoustic parameters and the next generation VibratoSleeve product. With all our testing and clinical study done, Vibrato will apply for US FDA 510(k) clearance of the product.