Allogeneic ABCB5-positive Dermal Mesenchymal Stromal Cells for Treatment of Therapy-resistant CVU (Phase III)

This is a pivotal, randomized, placebo-controlled, double-blind, multicenter, international phase III clinical trial to investigate the efficacy and safety of the IMP allo-APZ2-CVU on wound healing in patients with therapy-resistant non-healing CVU. The allogeneic IMP allo-APZ2-CVU contains skin-derived ABCB5-positive dermal mesenchymal stromal cells isolated from skin tissue of healthy donors and stored in a donor cell bank. Patients will be randomized to be treated with allo-APZ2-CVU or placebo. The patients will undergo treatment with the IMP on Day 0 (V3) and will be followed up for efficacy for 18 weeks (V4 until V14). Three safety follow-up visits will be performed at Month 6 (V15), Month 10 (V16) and Month 16 (V17). The wound healing process will be documented by standardized photography. The wound size measurement will start at the first Screening Visit (V1) and will be measured at each following on-site visit. Pain will be assessed using a numerical rating scale and quality of life will be investigated with standardized and validated questionnaires.