A Parallel-group Active Comparator, Double-blind, Multicenter, Randomized, Double-blind, Phase III Clinical Study

Parallel-group Active Comparator, Double-blind, Randomized, Phase III Study to Assess Safety, Efficacy of Glucosamine Sulfate Plus Meloxicam vs Glucosamine Sulfate Plus Chondroitin Sulfate Primary Symptomatic Knee Osteoarthritis Treatment

A multicenter, randomized, double-blind, parallel-group, placebo-controlled, and active-drug, 12-week, multicenter clinical study. Participants will be randomized 2: 2: 1 to receive the combination of glucosamine sulfate + meloxicam (experimental group), combination of glucosamine sulfate + chondroitin sulfate (active control group) or placebo.

A multicenter, randomized, double-blind, parallel-group, placebo-controlled, and active-drug, 12-week treatment period, phase 3 comparative clinical study. Participants will be randomized 2:2:1 to receive the combination of glucosamine sulfate + meloxicam (experimental group), combination of glucosamine sulfate + chondroitin sulfate (active control group) or placebo.

Inclusion Criteria:

1. Age of 40 to 75 years (both inclusive).
2. Clinical and radiological diagnosis of primary (idiopathic) knee osteoarthritis according to the American College of Rheumatology (ACR) criteria.
3. Radiological classification of Kellgren and Lawrence of grades 2 or 3 on X-ray of the target knee.
4. Presence of painful symptoms in the target knee in the last 3 months due to osteoarthritis.
5. Visual analogue scale for evaluation of knee osteoarthritis pain by the research participant ≥ 40 mm at the screening visit.
6. Mean score ≥ 40mm on the "pain" subscale (0 to 100mm) on the target knee of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire at the randomization visit.
7. ACR functional class from I to III.
8. Signature of the Informed Consent Form before performing any study procedure.

Exclusion Criteria:

1. Diagnosis of septic arthritis, inflammatory arthritis (such as rheumatoid arthritis), gout, pseudogout, Paget's disease, dysplasias or congenital articular anomalies.
2. Severe joint misalignment in the target knee, defined by the researcher.
3. History of severe trauma or surgery (including arthroscopy) in the target knee within 6 months prior to the study selection visit.
4. Symptomatic osteoarthritis of the ipsilateral hip.
5. Use of non-steroidal anti-inflammatory, dipyrone, opioid or narcotic analgesics, collagen and herbal remedies for osteoarthritis from the screening visit, or a washout period for such drugs less than those defined by the protocol, prior to the visit randomization. The use of antidepressants and pain modulating medicinal products should not be started from the screening visit, but they should be kept stable during the study if they are already being used prior to the screening visit.
6. Oral, intravenous or intramuscular corticosteroid therapy within 30 days prior to study visit visit.
7. Intra-articular injection of corticosteroids, hyaluronic acid and / or platelet-rich plasma at the target knee within 6 months prior to the study selection visit.