Efficacy and Safety of a Intra-articular Injection, ENKO1, in Patients With Symptomatic Knee Osteoarthritis.

Inclusion criteria

• Medial femorotibial compartment knee OA.
• Fulfilment of ACR criteria for knee OA (knee pain + grinding + stiffness in the morning < 30 minutes).
• Patients with a clinical course of disease longer than 6 months.
• Global pain score greater than 60 mm on a 0-100 mm VAS on the knee under study.
• Grade II or III according to the Kellgren and Lawrence classification system for the knee under study (on a posteroanterior X-ray performed under weight-bearing and for 6 months before randomisation).
• Patients taking analgesics for at least 3 months before randomisation and whom are dissatisfied with their current therapy.
• Patients who have given their consent in writing to take part in the study.
• Woman of childbearing age must take a urine pregnancy test which must be negative at the randomisation visit and be currently using an effective contraceptive method for at least 2 menstrual cycles (oral contraceptives, intrauterine device, tubal ligation or other effective procedures).

Exclusion criteria

• Isolated symptomatic patellofemoral osteoarthritis.
• Microcrystalline osteoarthritis.
• Prosthesis in knee under study.
• Joint lavage or arthroscopy or any surgery on the knee under study in the 6 months before randomisation.
• Paget's disease of bone, chondromatosis or villonodular sinovitis.
• Inflammatory, infectious or metabolic arthritis (rheumatoid arthritis, spondyloarthropathy or connective tissue diseases).
• Haemochromatosis, ochronosis or haemophilia.
• History of diseases that the investigator considers likely to interfere with the functional disability assessment.
• Knee surgery planned during the study period.

Other disease-related criteria:

• BMI greater than or equal to 30.
• Immunodeficiency or a serious or progressive disease (heart, lung, liver, kidney, haematological, neoplastic or infectious disease).
• Skin diseases or infections in the area of the injection site.
• Previous history of venous thromboembolism (including pulmonary embolism) or high risk of venous thromboembolism.
• Venous or lymphatic stasis of the leg under study.
• Severe acute or chronic disease that the investigator considers incompatible with the conduct of the study.
• Disease that the investigator considers likely to interfere with the study results or to expose the patient to an additional risk.
• Alcohol or drug abuse or dependence.

Previous or concomitant treatment-related criteria:

• Patients who have taken a SYSADOA, SERM or a drug/dietary supplement containing glucosamine, chondroitin sulfate, diacerein or avocado-soybean extracts in the 3 months before randomisation
• Patients who have taken paracetamol in the 24 hours before randomisation or any other symptomatic analgesic drug, including NSAIDs (except aspirin up to 325 mg/day for cardiovascular prophylaxis), in the 48 hours before randomisation
• Patients who have received any corticosteroid treatment by any route of administration (other than inhalers or the ocular or auricular routes) in the month before randomisation
• Patients who have received an intra-articular steroid injection in the knee under study in the month before randomisation or patients who have received intra-articular hyaluronic acid in the target knee in the 6 months before randomisation
• Patients who have received any local or topical treatment on the target knee in the 2 weeks before randomisation

Criteria related to concomitant medication:

• Hypersensitivity to paracetamol or NSAIDs

Study product-related criteria:

• Known allergy to the study treatments or to any of its ingredients.

Other criteria:

• Patients likely to be unable to comply with the protocol instructions and/or treatment, in the investigator's opinion
• Patients who have taken part in a clinical trial in the preceding 2 months or taking part in a trial at the time of randomisation
• Patients linguistically or mentally incapable of understanding the nature, objectives and possible consequences of the study; or who refuse to be subject to its limitations
• Patients who are family or colleagues (secretary, nurse, technician, etc.) of the investigator.
• Women: pregnant or breastfeeding