Clinical Study of Artz in the Treatment of Knee Osteoarthritis

Inclusion Criteria: 1. Adult Chinese subjects, at age≥18, either gender, diagnosed with osteoarthritis of the target knee and Kellgren-Lawrence (KL) classification Grade 1\~3, as evidenced by X-ray examination in the last 3 months (mild to moderate narrowing of joint space and / or marked osteophytes of tibiofemoral joint space) 2. Persist pain of the target knee after exercise, weight loss and physical therapy; 3. A baseline WOMAC A1 score for the target knee rated at 40-90mm (moderate to severe walk-associated pain) on 100mm Visual analogue scale(VAS); Able to understand and sign the Informed Consent Form (ICF) that has already been approved by the Independent Ethics Committee (IEC) Note: the informed consent may also be given by the duly authorized representative of the subject. Exclusion Criteria: 1. A diagnosis of bilateral knee osteoarthritis; 2. Clinically significant (requiring surgery) valgus or varus deformity of the knee joint, ligamentous laxity or unstable meniscus; 3. Complicated by inflammation or any other disease /condition (e.g., rheumatic arthritis, metabolic bone disease, psoriasis, gout, pseudogout, chondrocalcinosis, etc.) that may affect the knee joint; 4. A history of septicemia, clinically considered sub-acute infection of the target knee joint; 5. A history of surgery on the target knee (in the last 6 months); 6. A history of asthma, urticaria or allergy after use of aspirin or other non-steroidal anti-inflammatory drugs (NSAIDs); 7. Severe hepatic or renal disease or hepatic /renal failure; 8. Any unscheduled surgery on the lower limb; 9. Clinically significant lower venous or lymphatic obstruction; 10. Clinically significant obvious exudation or inflammation of the target knee; 11. Skin disorders or infection at the injection site; 12. Pregnant or lactating women; 13. Known allergy to guanylin and / or any active ingredient or excipient of hyaluronic acid-based injection / diclofenac sodium; 14. Treatment with any hyaluronic acid (HA) or its derivatives for the target knee within six months before this trial; 15. Intra-articular (IA) injection of steroids into the target knee within 3 months before this trial; 16. Presence of any contraindication to IA injection, e.g., patients who are receiving anti-coagulation therapy or clinically have potential coagulation disorders (e.g., hepatic disease); 17. Presence of any clinically significant disease (e.g., significant mental or nervous disorders, alcohol/drug abuse), unstable/poorly controlled diseases, or other factors, which may affect their evaluation or participation in this study in the investigator's judgment 18. Perioperative pain associated with coronary artery bypass surgery (CABG); 19. A history of gastrointestinal bleeding or perforation following use of NSAIDs; 20. Presence of active gastrointestinal ulcer /bleeding, or a past history of recurrent ulcer/bleeding; Chief complaint complicated by pain beyond the target knee,