A Pilot Study of Tumor Necrosis Factor Inhibition in Erosive/inflammatory Osteoarthritis of the Hands

Objective: To determine if anti-tumor necrosis factor (TNF) therapy (adalimumab) can safely improve symptoms of erosive/inflammatory osteoarthritis (EOA).

Methods: This was an open-label pilot trial in 12 patients with EOA. Patients > 45 years old with EOA of the hands defined by > or = 2 tender and > or = 2 swollen joints (distal interphalangeal, proximal interphalangeal, first carpometacarpal) despite nonsteroidal antiinflammatory drug therapy were eligible. Patients were excluded for autoimmune arthritis, recent disease modifying antirheumatic drug use, prior use of anti-TNF therapy, infection, malignancy, or poorly controlled medical conditions. All patients received adalimumab 40 mg every other week for 12 weeks. Safety was assessed 4 weeks after the final dose. Primary endpoints included safety and American College of Rheumatology (ACR) response.

Results: Patients were predominantly female with a mean age of 60 years and 12 years of arthritis. All patients completed the study and safety followup. Adverse events were mild without necessitating discontinuation of study drug. After 12 weeks, there was a statistically significant improvement in the number of swollen joints compared to baseline (p < 0.01). One patient achieved an ACR20 response and 42% achieved an OMERACT-OARSI response. Although we detected no statistically significant improvement in the number of tender joints, grip strength, disability, pain, or global disease assessments, trends suggested modest improvement in all efficacy measures.

Conclusion: This small open-label study of patients with EOA demonstrated that adalimumab was well tolerated. Treatment with adalimumab for 3 months did not significantly improve the signs and symptoms of EOA and most patients did not achieve an ACR20. Trends suggested improvement and individual patients had some benefit. Factors limiting interpretation of this study include the lack of a control group, outcomes chosen, number of patients treated, and the duration of treatment.