Safety and Efficacy of hUC-MSC for the Treatment of Cartilage Damage in the Knee Joint

All patients who provide written informed consent after receiving detailed information about the study and its potential risks will undergo a screening to assess eligibility. This is a prospective, multicenter, single-arm, open-label clinical trial. On Visit 1 (Day 0), eligible patients will receive knee surgery with a one-time application of the investigational product to the cartilage defect. Follow-up visits over a two-year period will be conducted at regular intervals to monitor the safety of the investigational product and to collect initial data on its efficacy.

Inclusion criteria

• Patients of any gender with an age from ≥ 18 years to ≤ 60 years
• Clinical indication for a surgical cartilage regeneration procedure
• Symptomatic grade III/IV cartilage defect according to ICRS or osteochondral defect with a maximum depth of 3 mm
• A cartilage defect requiring treatment with a defect size of 2-6 cm² on the femoral condyles or patella or trochlea
• Affected and contralateral knee (if known): Kellgren-Lawrence (K/L) osteoarthritis severity < grade III
• KOOS pain sub-score of ≤ 70 (out of max. 100) in the affected knee joint and > 80 (out of max. 100) in the contralateral knee joint measured without taking analgesics within the last 24 hours
• BMI < 35 kg/m²
• Written informed consent of the participant, also regarding alternative procedures such as cartilage transplantation (MACT) or matrix-augmented bone marrow stimulation (BMS, AMIC)

Exclusion criteria

• Clinical indication explicitly for a cartilage regeneration procedure other than the intended study treatment
• Known varus or valgus malalignment of the affected leg of ≥ 5°
• Antero-posterior or medio-lateral instability
• Meniscus loss of more than 20% in the affected compartment
• Patella instability
• Simultaneous surgery on other joint structures (cruciate ligament replacement, meniscus suture, partial meniscus resection > 20%, osteotomy)
• Simultaneous higher-grade (ICRS grade III/IV) cartilage damage on the corresponding joint surfaces to the treated cartilage damage ("kissing lesions")
• Osteoarthritis Kellgren-Lawrence (K/L) grade III or IV
• Arthrofibrosis
• Metabolic arthropathy
• Collagenosis
• Autoimmune disease
• Tumor disease within the last 5 years
• Neuromuscular disease
• Peripheral arterial occlusive disease
• Intra-articular application of hyaluronic acid or glucocorticoids or platelet concentrates within the last 6 months
• Joint replacement in the contra-lateral knee or hip within the last 12 months
• Rheumatoid arthritis or other inflammatory diseases such as autoimmune diseases, seronegative spondyloarthritis, gout, pseudogout
• Previous fracture in the affected knee joint
• Osteoporosis
• Contraindications against the planned operation under general anesthesia
• Relevant secondary diseases that increase the risk of surgery, e.g. cardiac insufficiency, coronary heart disease, coagulation disorders, diabetes mellitus, liver cirrhosis, renal insufficiency, etc.
• History of known hypersensitivity to porcine collagens, human albumin, glucose or components of fibrin adhesives used in orthopaedics or surgery
• Simultaneous participation in another interventional clinical trial (incl. within the last 4 weeks prior to inclusion)
• Addiction or other illnesses that do not allow the person concerned to assess the nature, scope and possible consequences of the clinical trial (lack of capacity to consent)
• Indications that the patient is unlikely to adhere to the protocol (e.g. lack of compliance)
• Persons who are placed in an institution by court or official order
• Persons who are dependent on the sponsor
• Pregnant or breastfeeding women
• Women of childbearing age, except women who meet the following criteria:

• Post-menopausal (12 months natural amenorrhea)
• Post-operative (6 weeks after bilateral ovariectomy with or without hysterectomy or bilateral salpingectomy)
• Presence of a negative pregnancy test (urine, not older than 14 days on the day of surgery) and willingness to regularly and correctly use a contraceptive method with a Pearl Index < 1 % per year:

3.1 Combined (oestrogen and progestogen-containing) hormonal contraception 3.2 Hormonal contraception containing progestogens (oral, injected, implanted) 3.3 IUD (hormonal IUD, copper IUD)

• Sexual abstinence
• Vasectomy of the partner