The goal of the interventional study is to assess the effectiveness of the supporting properties and safety of the dietary supplement ARTNEO (ARTNEO®), capsules with an average weight of 585 mg, in patients with osteoarthritis of the knee joint of both sexes aged 40 to 75 years. The main questions it aims to answer are:

1. To evaluate the effectiveness of the supporting properties of dietary supplement ARTNEO (ARTNEO®) in patients with knee osteoarthritis in comparison with active control;
2. To evaluate the safety of the dietary supplement ARTNEO (ARTNEO®) in patients with knee osteoarthritis

Inclusion Criteria:

• Voluntarily signed informed consent to participate in the study
• Men and women aged 40-75 years old, able to move independently, BMI 18-35 kg/m2
• Verified osteoarthritis involving the target knee according to the American College of Rheumatology (ACR) criteria at least 3 months prior to study entry, i.e. pain in the knee joint in combination with one of the following signs: crepitus in the joint or morning stiffness in the joint lasting less than 30 minutes in association with radiographic findings in the target knee joint
• X-ray stage I-III osteoarthritis in the target knee joint according to the Kellgren-Lawrence classification with a predominant lesion of the medial tibiofemoral area of the knee joint (X-ray of the target knee joint during the screening period or within 6 months prior to the screening visit)
• Regular associated pain in the target knee joint within the last 3 months
• Pain severity from 45 to 74 mm (moderate pain) on 100 mm VAS in the target knee joint after a washout screening period and confirmation of a 48-hour complete abstinence from rescue therapy (pain in motion (when starting a movement and walking around the office))
• Lequesne score of 5-7 for the joint being assessed after a washout screening period and confirmation of 48 hours of complete abstinence from rescue therapy;
• The ability to understand the rules of the study, the willingness to follow them, as well as the ability and ability to go through the procedures provided for in the study;
• Willingness to avoid the use of ibuprofen, aspirin (>100 mg/day), and other NSAIDs or other pain medications (OTC and prescription) other than paracetamol as a "rescue drug" throughout the study (maximum dosage allowed per protocol) 1,500 mg per day, with a complete withdrawal required 48 hours before Visits 2 - 6 and Visit 9)
• Willingness to refuse complementary and alternative medicine therapy, as well as willingness to restrict diet (excluded soy, avocado, passion fruit, pineapple, turmeric, foods enriched with ω-3 fatty acids, decoction of willow bark, pine, mugwort, L-carnitine, acupuncture and etc.)
• Women of childbearing potential must have a negative pregnancy test at screening (except women who have had a hysterectomy or who have gone through menopause for more than 2 years)

Exclusion Criteria:

• Pregnancy, lactation or planning pregnancy during the study period

• Individual intolerance to the active or excipients of the dietary supplement ARTNEO (non-denatured type II collagen + methylsulfonylmethane + Boswellia serrata extract + vitamin C + Vitamin D3), the reference drug and the "rescue drug" paracetamol (acetaminophen)

• Intolerance to eggs, poultry, shellfish;

• History of trauma or surgery on the target knee joint (other than diagnostic arthroscopy more than 60 days old at study entry), expected surgery (within 6 months following inclusion)

• Positive test results for HIV, viral hepatitis B or C, syphilis.

• Diseases that, from the point of view of the investigator, put the patient's health at risk if participating in the study or potentially make it difficult to interpret the results of the study (may affect the assessment of endpoints)

• Known or suspected malignancy at the time of screening or in the previous 2 years, other than completely healed skin cancer in situ;

• Immune-inflammatory joint disease, systemic connective tissue disease, or severe osteoarthritis (target joint after washout screening period and 48-hour complete withdrawal of rescue drug, motion VAS score > 74 mm and/or Lequesne score > 7 points), systemic red lupus

• History of gout

• Diseases of the gastrointestinal tract: enteritis, colitis, Crohn's disease, irritable bowel syndrome, ulcerative colitis and any other diseases of the gastrointestinal tract, which, in the doctor's opinion, may affect the absorption and assimilation of the active components of the drugs, in particular, the formation of the mechanism of oral immunotolerance to undenatured collagen

• Hemophilia and other hemorrhagic diathesis, as well as taking anticoagulants and antiplatelet agents

• Fibromyalgia and other chronic pain syndromes

• Impaired kidney function (GFR less than 60 ml / min / 1.73 m2 as assessed by the Cockcroft-Gault formula at the screening visit), severe chronic renal failure

• Severe liver dysfunction (ALT, AST levels 3 times or more above the upper limit of normal, and / or total bilirubin level 1.5 times or more above the upper limit of normal)

• Mental and / or neurological diseases with partial or complete loss of legal capacity

• Presence or suspicion of drug, alcohol or drug addiction

• Intra-articular injection in the target knee joint:

  1. Hyaluronates - less than 6 months prior to randomization
  2. Other high molecular weight synovial fluid prostheses in less than 24 months
  3. Glucocorticosteroids - less than 1 month prior to randomization visit
  4. NSAIDs less than 3 weeks before randomization

• The need for stable use of glucocorticosteroids in any dosage form

• Failure to comply with the washout screening period and 48 hours of complete withdrawal of the rescue drug (immediately prior to baseline measurement at Visit 2, Day 1) in relation to prohibited therapy, in particular the use of paracetamol, ibuprofen, aspirin or other NSAIDs, any pain medication in any drug form, as well as some natural products (such as soy, avocado, passion fruit, pineapple, turmeric, products enriched with ω-3 fatty acids, decoction of willow bark, pine, wormwood), L-carnitine

• Use of glucocorticosteroids, SYSADOA (Symptomatic Slow-Acting Drugs in Osteoarthritis) in the period of 3 months before randomization

• Use of ω-3 polyunsaturated fatty acid preparations in the 6 months prior to randomization (a 2-week washout period is allowed), therapeutic doses of fish or vegetable oils (≥ 2 g/day), shark cartilage preparations

• Participation in another clinical study at present or in the previous 30 days or 5 half-lives (whichever is longer) prior to the Screening Visit

• History of treatment with oral undenatured type II collagen or anti-tumor necrosis factor (TNF) antibodies