Gastro-protective Effect and Pain Relief Effect of Naxozol Compared to Celecoxib in Patients With Osteoarthritis

Inclusion Criteria: * Koreans given informed consent * Patients who have ability of reading comprehension and completing questionnaires (EQ-5D and VAS)and have willingness to follow-up 12 weeks * Patients with osteoarthritis symptoms confirmed by his/her medical history and with pain-VAS of 40 and more Exclusion Criteria: * Patients who participate into other interventional study or had participated within 30 days before screening * Alcohol or drug abuse within 6 months or alcohol consumption of 21 units and more in a week * Peptic ulcers accompanied with a complication such as bleeding, perforation, penetration or gastric outlet obstruction within 5 years, or a history of active peptic ulcer or peptic ulcer without a complication within 6 months at screening * Patients who are known with Helicobacter pylori infection but have not received any bacteriostatic treatment * Known gastroesophageal reflux disease (GERD) * Any following joint diseases which may significant effect to the efficacy and safety assessments: septic arthritis, inflammatory joint arthritis such as rheumatoid arthritis, gout, recurrent pseudo-pain, Paget's disease, joint fracture, joint ochronosis, acromegaly, hematochromatosis, Wilson's disease, primary osteochondrosis, Ehlers Danlos Syndrome, or other collagen genetic disorder * Patients who are scheduled admissions to hospital for elective surgery during this study * History of gastrointestinal cancer * Gastrointestinal disorders related to drug malabsorption * Gastrointestinal bleeding, cerebral bleeding, other bleeding disorders, or severe hematological disorders * Clinically significant diseases such as moderate or severe liver diseases (Child Pough Class II or more), severe heart failure or a history of coronary artery bypass graft (CABG), severe kidney diseases (CrCl\<30ml/min) * Know allergy experiences with any ingredient of study drugs or with other NASIDs or protocol pump inhibitors (PPIs) * Patients who had had a joint surgery for osteoarthritis within 1 year * Women of childbearing potential who do not agree with clinically appropriate contraception during this study