Evaluation of the effect of choline-stabilized orthosilicic acid on the symptoms of knee osteoarthritis

INTERVENTION: Participants are randomized to either the placebo or active treatment group (choline‐stabilized orthosilicic acid) using block randomization in a ratio of 1:1. All participants will be instructed to take daily for 9 months, two capsules orally of either placebo (520 mg microcrystalline cellulose beadlets), or the active ingredient (520 mg beadlets containing 5 mg of silicon and 100 mg of choline in the form of choline‐stabilized orthosilicic acid). The trial starts with a screening visit and a wash‐out period during which the use of knee‐osteoarthritis medication is not permitted. Assessments will be done respectively at inclusion (baseline) and after 2, 6, 12, 18, 24 and 36 weeks. CONDITION: Knee osteoarthritis ; Musculoskeletal Diseases ; Gonarthrosis [arthrosis of knee] PRIMARY OUTCOME: The sum of physical function, stiffness and pain scores measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total index at baseline and 36 weeks INCLUSION CRITERIA: 1. Provision of written informed consent 2. Males and females between the ages of 18 and 75 years old 3. Females must use an approved form of birth control or be postmenopausal or be surgically sterile 4. OA of the knee as confirmed by radiography (weight‐bearing, anteroposterior radiograph of the target knee: Kellgren and Lawrence grade II and III) during the screening visit or by a recent radiograph (<6 months before baseline) 5. OA of one or both knees prior to administration of study dietary supplement based on the American College of Rheumatology criteria23: 5.1. Knee pain for most days of previous month 5.2. Osteophytes at joint margins on radiographs 5.3. Age >50 years 5.4. Crepitus on active joint motion 5.5. Morning stiffness lasting <30 min Criteria SECONDARY OUTCOME: ; 1. The sum of functional, stiffness and pain scores measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total index at baseline, 2, 6, 12, 18, 24 and 36 weeks; 2. Pain scores measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale at baseline, 2, 6, 12, 18, 24 and 36 weeks; 3. Physical function scores measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) physical function subscale at baseline, 2, 6, 12, 18, 24 and 36 weeks; 4. Stiffness scores measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) stiffness subscale at baseline, 2, 6, 12, 18, 24 and 36 weeks; 5. The subject's global assessment of response to treatment measured using a visual analogue scale 100 mm at baseline, 2, 6, 12, 18, 24 and 36 weeks; 6. Paracetamol intake measured using a diary and counting the remaining medication at 2, 6, 12, 18, 24 and 36 weeks; 7. Biomarkers of collagen type II degradation and cartilage oligomeric matrix measured in serum and urine samples taken at baseline, 2, 6, 12, 18, 24 and 36 weeks; 8. Response to treatment, defined by the OsteoArthritis Research Society International (OARSI) and Outcome Measures in Rheumatology Group (OMERACT) committees as at least 50% (or absolute score of 20) improvement in pain scores or improvement in at least two of the three following: at least 20% (or absolute score of 10) improvement in pain scores, at least 20% (or absolute score of 10) improvement in physical function scores, at least 20% (or absolute score of 10) improvement in subjects global assessment. The pain and physical function score scores are measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and physical function subscores. The subject's global assessment is measured using a 100 mm VAS score; 9. Response to treatment, defined as 30% decrease in pain scores measured using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale at baseline, 2, 6, 12, 18, 24 and 36 weeks;