Inclusion Criteria:
1. Meets the diagnostic criteria for knee osteoarthritis (OA), with unilateral or bilateral knee involvement
2. Prior to randomization, the NRS pain score of the target knee joint ≥4, and the NRS score of the contralateral knee joint is not higher than that of the target knee joint; among the 5 pain items on the WOMAC, at least 1 item scores ≥40 mm
3. Body Mass Index (BMI) ≤32 kg/m²
4. Meets the diagnostic criteria for Qi and Blood Deficiency Pattern
5. Age between 40 and 75 years inclusive (40 years ≤ age ≤ 75 years), male or female
6. The Kellgren-Lawrence grading of the target knee joint is grade I-III, and the Kellgren-Lawrence grading of the contralateral knee joint is not higher than that of the target knee joint (in cases of unilateral disease, the affected side is the target knee joint; in cases of bilateral disease, the target knee joint must satisfy the above criteria)
7. Voluntarily participates in this clinical trial, provides informed consent, and signs the informed consent form
Exclusion Criteria:
1. Other conditions exist that may confound the assessment of function and pain in the target knee joint, such as: systemic diseases that may involve the joints (e.g., gouty arthritis, rheumatoid arthritis, etc.), chronic inflammatory or connective tissue diseases, neurological disorders, Paget's disease involving the knee, localized pain resulting from radicular lumbar compression, and any other conditions that may interfere with the efficacy assessment
2. Use of other Chinese or Western medicines or therapies for osteoarthritis within one week prior to screening (excluding celecoxib tablets): such as non-steroidal anti-inflammatory drugs (excluding aspirin at no more than 325mg daily for cardiovascular disease prevention) , analgesics (including opioids, non-steroidal anti-inflammatory drugs, cyclooxygenase-2 (COX-2) inhibitors, tramadol, ketamine, clonidine, gabapentin, pregabalin and/or cannabinoids), or traditional Chinese medicine formulations with similar therapeutic indications to Knee Pain Ejiao Paste (i.e., those possessing qi-tonifying and blood-nourishing effects)
3. Use within 4 weeks prior to screening of drugs that relieve osteoarthritis (OA) symptoms (such as glucosamine, chondroitin sulfate, diacerein, etc.), any nutritional supplements with potential activity on articular cartilage, systemic corticosteroids or immunosuppressive drugs (subjects requiring only inhaled corticosteroids for asthma treatment may be enrolled)
4. Receipt of biological products or intra-articular drug injection therapy (e.g., glucocorticoids, sodium hyaluronate, medical chitosan, growth factors, platelet-rich plasma, stem cell therapy, etc.) within 3 months prior to screening
5. Invasive procedures such as arthroscopy or lavage of the target knee joint within 6 months before screening or planned during the study period
6. Previous or planned target knee joint replacement (partial or total), autologous osteochondral mosaicplasty, microfracture, meniscectomy, osteotomy or other surgery during the study period
7. Planned change or new use of mobility aids (e.g., wheelchair, walker, cane or crutch) or need for lower limb prosthesis and/or structural knee brace during the study period
8. Investigator-judged serious comorbid cardiovascular, cerebrovascular, gastrointestinal diseases, poorly controlled hypertension (systolic blood pressure ≥160 mmHg and/or diastolic blood pressure ≥100 mmHg), or other conditions that could affect the assessment of the investigational product's efficacy and safety
9. Laboratory abnormalities: alanine aminotransferase (ALT) or aspartate aminotransferase (AST) \>1.5 times the upper limit of normal (ULN), or creatinine (Cr) \>ULN
10. Known or suspected allergy to the investigational product, rescue medication, or any of their components
11. Pregnant or lactating women, or women of childbearing potential planning pregnancy from enrollment through 3 months after the end of the study
12. Known or suspected history of alcohol or drug abuse
13. Intellectual disability, psychosis, or neurosis
14. Subjects who participated in any interventional drug clinical trial and received the investigational drug within 3 months prior to enrollment, or who are within 5 half-lives (whichever is longer) of any other clinical trial drug
