A Study of Econoglutide Injection in Obese Participants With Knee Osteoarthritis (KOA)

The main purpose of the study is to evaluate the efficacy and safety of ecnoglutide injections versus placebo in obese participants with KOA.

Inclusion Criteria: 1. Body mass index (BMI) ≥ 28.0 kg/m\^2; 2. The target knee must meet the diagnostic criteria of American College of Rheumatology (ACR) for knee osteoarthritis (clinical and radiological), with moderate radiographic changes (Kellgren-Lawrence grade 2 or 3). The target knee is defined as the knee with the most symptomatic knee at screening period; if pain in both knees are equal, the target knee will be the most dominant leg (preferred leg); 3. Prior to screening, target knee pain lasting more than 12 weeks, and according to participant's self-report or medical history at screening, target knee pain lasting more than 15 days in the past month; 4. At screening and prior to randomization, WOMAC pain score (NRS 0-10) of the target knee must be between 4 and 9 (to avoid bias in reporting, participants must not be informed of the pain score used to determine eligibility for the study); 5. Self-reported by the participant who has a history of unsuccessful weight loss attempt by diet and exercise. Exclusion Criteria: 1. The target knee has undergone joint replacement surgery; 2. The target knee has undergone arthroscopy within 12 months prior to screening; 3. At the time of screening, the target knee joint has any clinical features and symptoms of other active infections or crystal-induced arthropathies, as well as any other active joint diseases that may interfere with assessment; 4. The target knee has received intra-articular injections of hyaluronic acid, any other investigational drugs, or biologics within 3 months prior to screening; or has undergone any procedures that result in persistent sensory loss in the target knee (e.g., ablation) within 6 months prior to screening; 5. Has received any intramuscular or oral corticosteroids (investigational or marketed) within 30 days prior to screening, or has received any intra-articular corticosteroid injections (investigational or marketed) in any joint within 90 days prior to screening; 6. History of joint instability in either knee within 12 months prior to screening, such as anterior cruciate ligament rupture or recent trauma; 7. History of any other potentially causative and/or confounding diseases, including Reiter's syndrome, rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, inflammatory bowel disease-associated arthritis, sarcoidosis, amyloidosis, or fibromyalgia; 8. Presence of symptomatic hip osteoarthritis at the time of screening, with the exception of those who have undergone hip replacement surgery; 9. Conditions that may interfere with the assessment of target knee pain during screening include, but are not limited to: * Pain in any part of the lower limb or back equal to or more severe than the pain in the target knee; * Pain radiating to the knee from other areas, such as hip pain affecting the knee or radicular pain; * Chronic widespread pain (including neuropathic pain); 10. Change of body weight \>5% within 3 months prior to screening (selfreported); 11. Diagnosis of diabetes (excluding gestational diabetes), or with a history of diabetic ketoacidosis or hyperosmolar state/coma