We will conduct a pilot study of the effectiveness of adalimumab for inflammatory osteoarthritis.

This is a 20 patient pilot open-label study of the efficacy of adalimumab in inflammatory osteoarthritis of the knee. Primary endpoint is at 12 weeks and primary outcome is the OARSI responder index.

Inclusion Criteria:

• Patient is 40 years of age or older.
• If female, patient is either not of childbearing potential, defined as postmenopausal for at least 1 year or surgically sterile (bilateral tubal ligation, bilateral oophorectomy or hysterectomy), or is of childbearing potential and practicing one of the following methods of birth control: condoms, sponge, foams, jellies, diaphragm or intrauterine device (IUD) contraceptives (oral or parenteral) for three months prior to study drug administration),a vasectomized partner, total abstinence from sexual intercourse
• If patient is female and of childbearing potential, the results of a serum pregnancy test performed at Screening, prior to the first dose of adalimumab, must be negative.
• Patient has a diagnosis of OA of the index knee according to American College of Rheumatology criteria, including radiological evidence of OA (Kellgren-Lawrence grades 2 or 3).
• Patient has had continual pain for at least 6 months prior to inclusion in the study. This includes pain that has persisted despite conventional treatment, defined as any one of the following medications taken daily during the preceding month:acetaminophen (2- 4 grams per day)maximum tolerated and recommended doses of an NSAID, acetaminophen/codeine combination (i.e. Tylenol No 2, 3, 4) taken at least 3 times daily
• Patient has had daily knee pain for the month preceding study enrolment.
• Patient has a summed pain score of 125-400mm (visual analog scale) on the WOMAC pain sub-scale in the index (more symptomatic) knee.
• Patient has clinical evidence of a knee effusion in the index (more symptomatic) knee at Screening and Baseline.

Exclusion Criteria:

• Subject has a history of an allergic reaction or significant sensitivity to constituents of Adalimumab.
• Patient has a history of proven systemic arthritis such as rheumatoid arthritis.
• Patient has a concurrent medical or arthritic condition that could confound evaluation of the index joint e.g. post-traumatic or any secondary form of knee OA
• Patient has predominant patellofemoral disease