Treatment of refractory rheumatoid arthritis with a monoclonal antibody to intercellular adhesion molecule 1

Objective. To assess the safety and efficacy of a monoclonal antibody (MAb) to intercellular adhesion molecule 1 (ICAM‐1; CD54) in rheumatoid arthritis (RA). Methods. A phase I/II, open‐label, dose‐escalation study of 32 patients. Results. During treatment, a peripheral CD³⁺/CD4+ lymphocytosis was noted, and several patients demonstrated transient cutaneous anergy, which suggests that therapy modified T cell recirculation. Thirteen of the 23 patients who received 5 days of treatment demonstrated clinical improvement through day 29, and 9 of 23 through day 60. Adverse effects were minor and transient. Conclusion. Anti—ICAM‐1 MAb therapy was well tolerated, resulted in a transient alteration in T lymphocyte recirculation, and effected clinical improvement in some RA patients.