This study was performed to demonstrate that treatment with valdecoxib 10 mg daily (QD) was at least as effective as with naproxen 500 mg twice daily (BID), a standard non-steroidal anti-inflammatory drug (NSAID), when taken for 6 weeks in Korean subjects with symptomatic osteoarthritis (OA) of the knee. Secondary objectives were to assess the overall safety and tolerability of valdecoxib 10 mg QD taken for 6 weeks in Korean subjects with symptomatic OA of the knee.

Inclusion Criteria:

• Korean outpatients with symptomatic radiologic evidence of OA of the knee (diagnosed according to the modified American College Rheumatology criteria)
• Patient's Assessment of Arthritis Pain measurement of at least 40 mm on VAS
• Patients had not received any NSAIDs or analgesics within 2 days (within 4 days for subjects taking oxaprozin, piroxicam or full dose aspirin) prior to the Baseline Visit

Exclusion Criteria:

• Diagnosis of inflammatory arthritis, gout, pseudogout, Paget's disease, or any chronic pain syndrome that, in the Investigator's opinion, would interfere with the assessment of the Index Knee
• Symptomatic anserine bursitis or acute joint trauma of the Index Knee
• Arthroscopy performed on the Index Knee within the past 12 months
• Complete loss of articular cartilage of the Index Knee
• Administration of oral, or intramuscular, intravenous, or soft tissue injections of corticosterosteroids within 4 weeks prior to screening visit
• Administration of intra-articular injection of corticosteroids or hyaluronic acid preparation in the Index Knee within 3 months or 6 months, respectively