The purpose of this study is to expose patients with OA to calcitonin and to determine plasma calcitonin levels after administration of 0.6 mg and 0.8 mg oral calcitonin. Also the purpose is to assess the effect of different doses of oral calcitonin (0.6 mg and 0.8 mg oral) compared to placebo on serum CTX-I and CTX-II. Finally to assess the tolerance profile of different doses/formulations of oral calcitonin compared to placebo.

Inclusion Criteria:

• Medical history and symptoms of knee osteoarthritis

Exclusion Criteria:

• Any other disease or medication affecting the bone or cartilage.
• Any clinical signs or laboratory evidence diseases, which in the Investigator's opinion would preclude the participant from adhering to the Protocol or completing the trial.