Edelweiss callus culture extracted exosome for chronic wound healing.

Chronic lower-extremity ulcers remain difficult to treat, particularly in patients with metabolic and vascular comorbidities. This multicentre case series describes four patients with chronic lower-extremity ulcers that persisted for at least 6 months despite conventional management. The study evaluated topical application of edelweiss callus culture extract-derived exosomes (P198 Exo-HL FILCORE SB PLUS, Primoris International Co., Ltd., Seoul, Korea) used as an adjunct to standard wound care. All ulcers had persisted for at least 6 months despite conventional management. After wound cleansing and debridement as required, exosomes (0.5-1.0 mL; approximately 0.1 mL/cm²) were applied directly to the wound bed at monthly visits, followed by non-adherent sterile dressings. Clinical progress was documented by serial photography and wound measurements. Arterial and venous Doppler ultrasonography was performed at baseline and at 3-month intervals to assess changes in perfusion and venous reflux. Across the series, all patients demonstrated progressive granulation and re-epithelialisation without treatment-related adverse events. Early size reduction was observed within 15 days in one case, complete granulation and re-epithelialisation occurred within 60 days in another, and near-complete closure was achieved over 5-7 months in a third. In a severe post-infective ulcer for which amputation had been recommended, complete closure was achieved over approximately 6 months. Doppler parameters improved in all cases, including reductions in resistive index and venous reflux time and/or increases in peak systolic velocity. This small, uncontrolled series suggests that topical exosome therapy may be a feasible adjunct in refractory chronic ulcers, with concurrent improvements in clinical healing and Doppler-assessed vascular dynamics. Larger controlled studies are required to define efficacy and optimal treatment schedules.