Study of the Effect of Chondroitin Sulfate on Structural Changes in Knee Osteoarthritis Patients Assessed by MRI

To compare the cartilage volume loss of the lateral compartment (femoral condyle and tibial plateau) at the Baseline visit and after 12 and 24 months of treatment either with CHONDROITIN SULPHATE (CONDROSAN) 1200 mg daily or with CELECOXIB 200 mg daily.

To compare the cartilage volume loss of the global knee at the Baseline visit and after 12 and 24 months.

To compare the cartilage volume loss of the medial compartment at the Baseline visit and after 12 and 24 months.

To compare the severity of synovitis score (Thickness of the Synovial Membrane in mm) in Global Knee , at the baseline visit and the follow-up visits in subjects treated either with CHONDROITIN SULPHATE (CONDROSAN) or CELECOXIB.

The severity of synovitis was evaluated through four regions of interest (ROIs) in the images of the axial T1-weighted acquisition complemented with the use of the images of the axial T2-weighted acquisition. The thickness of the synovial membrane was evaluated in the global knee and each of the ROIs and results were expressed in millimetres. The four ROIs were the proximal lateral, distal lateral, proximal medial and distal medial.

To compare the bone marrow lesions (BMLs) score in the global knee and the different sub regions at the baseline visit and the follow-up visits in subjects treated either with CHONDROITIN SULPHATE (CONDROSAN) or CELECOXIB.

The BMLs were assessed in the global knee and the different sub region of the knee (medial trochlea, plateau of the medial femoro-tibial joint, femur of the medial femoro-tibial joint, medial posterior condyle, lateral trochlea, plateau of the lateral femoro-tibial joint, femur of the lateral femoro-tibial joint, lateral posterior femur). The BMLs score was defined as a grade (between 0 and 3) in each knee sub region and summed to derive a global knee score ranging between 0 (absent) and 30 (present). Specifically, each grade was scored as follows:

• Grade 0 = Absence of lesion in the sub region
• Grade 1 = less than 25% of the surface
• Grade 2 = 25-50% of the surface
• Grade 3 = more than 50% of the surface

To compare the synovial fluid volume of the global knee at the Baseline visit and after 24 months.

The presence of a meniscal extrusion was assessed in each of sub regions. The absence of a severe extrusion in all the sub regions was considered as an absence (score=0) of a severe extrusion in the meniscus. The presence of a severe extrusion in at least one region of the meniscus was sufficient to consider the presence (score=1) of a severe extrusion in the meniscus.

Visual Analogue Scale: 0 No Pain 10 Maximum Pain Huskisson's VAS measures global pain intensity. Patients were asked to quantify their disease status on a 10 cm VAS as follows: "Please indicate the severity of knee pain experienced during the last 48 hours by marking a (I) through the line". Left hand marker represents "No pain" and right hand marker represents "The worst pain imaginable".

Western Ontario & McMaster Universities Osteoarthritis Index (WOMAC) Pain subscale Score Range: 0 (no pain) - 50 (maximum pain) The study was designed such that the outcome of primary interest is knee pain related to OA. The measure selected to best evaluate this is an improvement in the WOMAC pain subscales. This subscale consists of 5 items which assesses the pain during walking, using stairs, in bed, sitting or lying, and standing.Each item is a 10 cm VAS with 0 and 10 cm representing no pain and extreme pain respectively.

Western Ontario & McMaster Universities Osteoarthritis Index, from 0 No Stiffness to 20 Maximum Stiffness WOMAC stiffness subscale was used to measure the stiffness of the knee with pain. Two items are used to assess stiffness grade: after first waking and later in the day.Each item is a 10 cm VAS with 0 and 10 cm representing no difficulty and extreme difficulty respectively.

Western Ontario & McMaster Universities Osteoarthritis Index, from 0 No Function to 170 Maximum Function WOMAC functional limitation subscale was used to measure the functionality of the knee with pain. Seventeen items are used to assess functionality of the knee: tair use, rising from sitting, standing, bending, walking, getting in / out of a car, shopping, putting on / taking off socks, rising from bed, lying in bed, getting in / out of bath, sitting, getting on / off toilet, heavy household duties, light household duties. Each item is a 10 cm VAS with 0 and 10 cm representing no difficulty and extreme difficulty respectively.

The SF-36 is composed of 35 items measuring:

• 8 health concepts (or dimensions), [(Physical Functioning (PF), Role Physical (RP), Bodily Pain (BP), General Health (GH), Vitality (VT), Social Functioning (SF), Role Emotional (RE) and Mental Health (MH)]
• and 1 reported health transition item.

The 8 health concepts are summarized in 1 physical (PCS) and 1 mental (MCS) component summary measures. PCS is represented by physical function, role limitations-physical, pain, and general health perception. MCS is represented by vitality, social function, role limitations-emotional, and mental health. Subscale items are summed and scaled from 0-100 to give subscale scores; 0= worst health related quality of life (HRQL), 100=best HRQL. PCS and MCS summary scores are constructed as T-scores (mean =50, standard deviation=10) with no minimum or maximum score; higher scores indicate better health status.

Study knees were evaluated at each visit for the presence or absence of swelling and effusion.

Consumption of Acetaminophen: At each post-baseline visit, the investigator had to assess the consumption of acetaminophen, rescue analgesic authorised throughout the study, by reporting the number of caplets dispensed/retrieved since the previous visit.

Daily consumption of acetaminophen was calculated as an average.