Primary objective:

• To assess therapeutic efficacy of the Ketoprofen compared with Diclofenac based on the assessment of primary endpoint : Mean change in walking arthritis pain intensity score

Secondary objectives:

• To assess therapeutic efficacy of the Ketoprofen compared with Diclofenac based on the assessment of secondary endpoints.
• To assess safety and tolerability of the Ketoprofen compared with Diclofenac based on the nature and frequency of adverse events in treatment groups

This trial is designed as an open-label, multicenter, randomized, clinical study for assessment of efficacy and safety of Ketoprofen plaster and Diclofenac plaster in patients with osteoarthritis

Inclusion Criteria:

• Patients aged 40-75 years
• Compliance to ACR diagnostic criteria of OA of the knee
• Patients with Kellgren-Lawrence grade 1-3
• Index knee pain should be ≥40 mm on VAS (100mm) scale

Exclusion Criteria:

• Intolerance or allergic reactions to the study therapy
• Usage of NSAIDs within 3 days
• Open skin lesions or dermatological conditions at the site of plaster application
• Surgery or major trauma of the index knee within the previous 12 months
• Pregnant or breast-feeding women
• Alcohol addiction, drug addiction or drug abuse in the past