Repeat treatment of rheumatoid arthritis patients with a murine anti- intercellular adhesion molecule 1 monoclonal antibody

Objective. To assess the safety and efficacy of a second course of treatment with a murine monoclonal antibody (MAb) to intercellular adhesion molecule 1 (ICAM-1; CD54) in active rheumatoid arthritis (RA). Methods. In an open-label study, 8 patients who had previously received a course of anti- ICAM-1 MAb received a second course. Results. The second course of therapy was associated with adverse effects suggestive of immune complex formation. Such adverse effects were not seen during the initial course of therapy. Clinical efficacy associated with the second course of therapy was less than that observed in the first course. Conclusion. Repeated courses of therapy with a murine MAb to ICAM-1 would probably not be a useful therapeutic strategy in patients with RA, probably because of its immunogenicity.