Safety and Preliminary Efficacy of TrophiPatch, an Adipose-Derived Stromal Cell Patch for Chronic Leg Ulcers

Inclusion Criteria * Age 18 years or older. * Patients with more than one eligible ulcer will have one - usually the largest or more clinically significant - selected at screening as the index ulcer. * Participants will have the capacity to understand study procedures, and will be able to providewritten informed consent. (for VLU only) * Diagnosed with at least one venous leg ulcer. * Ulcers duration for 6 weeks to 3 years at the time of screening. * Hard-to-healed ulcers with cross-sectional area that have decreased by less than 40% during a four-week run-in period. * Reference ulcer surface from 5 to 25 cm2. * At the time of inclusion, the ulcer will be clinically non-infected (TILI score ≥ 5). * Absence of significant arterial insufficiency assessed at clinical examination (intermittent claudication or resting pain, necrotic or distal wound on the foot) and systolic homolateral ankle-brachial index (ABI) greater than 0.75 and inferior to 1.40 or biphasic or triphasic Doppler signals in the dorsalis or posterior tibial arteries of the affected limb. (for DFU only) * Patient with type 1 or type 2 diabetes. * Diagnosed with at least one diabetic foot ulcer on a foot or both feet below the level of the malleoli, excluding ulcers confined to the interdigital cleft. * Ulcers duration for 4 weeks to 3 years at the time of screening. * Eligible ulcers will be hard-to-heal, meaning that the cross-sectional area will decrease by less than 50% during a four-week run-in period. * Reference ulcer surface from 1 to 25 cm2. * At the inclusion, the ulcer will be clinically non-infected (according to IDSA criteria). * HbA1C \< 12% at screening. * Absence of significant arterial insufficiency assessed by systolic homolateral ankle-brachial index (ABI) greater than 0.75 and inferior to 1.40 or biphasic or triphasic Doppler signals in the dorsalis or posterior tibial arteries of the affected limb. Exclusion Criteria * Subject has a history of: * endstage renal disease * uncontrolled cardiac failure * severe malnutrition * severe liver disease * aplastic anemia * malignant disease (active or recent (\<5 years))diabetes avec HbA1C \> 12% * rheumatoid arthritis * sickle cell disease * other connective tissue disorder * irradiation to the affected extremity * Serum creatinine concentration greater than 180 umol/L and/or receipt of renal dialysis or an estimated glomerular filtration rate (based on cystatin C or serum creatinine) of less than 20 mL/min per 1·73 m² * Drug or alcohol abuse. * Limited physical capacity or total immobility. * Known pregnancy or nursing at the time of screening visit * Subject is currently receiving (i.e within 30 days prior to inclusion) or scheduled to receive a medication or treatment that, in the opinion of the investigator, will interfere with or affect the rate of wound healing. * Index ulcers probing to tendon, muscle, capsule and bone. * Local or systemic signs of ongoing infection. * Hypersensitivity to silicone or porcine gelatin. * Previous treatment with growth factors, stem cells, or an equivalent preparation within the 8 weeks before the baseline visit. * Involvement in another interventional clinical trial within the 4 weeks before the baseline visit. * Known or suspected absence of capacity to understand the study procedures or provide written informed consent (decided by the investigator). * Cross-sectional area of the index ulcer had increased by at least 20%. (for VLU only) * History of poor compliance with compression therapy. * Presence of peripheral neuropathy of the lower limbs. (for DFU only) • History of poor compliance with offloading therapy.