This is a double-blinded, placebo-controlled, randomized trial to assess the efficacy of oral solution of hyaluronic acid mixture (A+ HA(tm)). During 8 weeks treatment period, there were three follow-up visits requested (Week 2, Week 4 and Week 8).

Subjects were initially screened at the Randomization/Baseline Visit (Week 0). Eligible subjects were randomized at the same visit into treatment period, and received the assigned treatment in a double-blind fashion for 8 weeks. Efficacy was measured by the several questionnaire including Knee injury and Osteoarthritis (KOOS), the Short Form-36 (SF-36) and Pittsburgh Sleep Quality Index (CPSQI) for each visit. Incidences of adverse events (AEs) were monitored for each subject once the subject had received 1 dose of study medication; the incidence of serious AEs (SAEs) were monitored for each subject once the subject had signed the informed consent through to the End-of-Study or ET Visit. Vital signs were measured at baseline and End-of-Study or ET Visit.

Inclusion Criteria:

1. Age >= 40 years old
2. Male or Female
3. With osteoarthritis of the knee based on the definition of Ahlback 1968 and with significant symptoms within 30 days before enrollment.
4. No limitation for use of concomitant medication

Exclusion Criteria:

1. Use of Glucosamine within 1 month before enrollment
2. Osteoarthritis of the knee due to exercise or occupational injury
3. Allergy with Oral Hyaluronic Acid
4. Bilateral Total Knee Replacement
5. Pregnant
6. Need use wheelchairs
7. BMI≥40
8. With at least one condition: Known other causes of arthritis (infectious arthritis, rheumatoid arthritis, connective tissue disease, gout, pseudogout, or psoriatic arthritis), bony or soft tissue malignancy or skin lesions or peripheral neuropathy involving the lower extremities, cardiopulmonary disease which limits walking more than knee pain. Knee instability defined as report of knee bucking or locking within the past month of the study knee, major neurologic deficit that affects gait, psychiatric illness that limits informed consent, and parkinsonism.
9. Cancer