A pilot study using a staph protein A column (Prosorba) to treat refractory rheumatoid arthritis

To assess the safety and effectiveness of extracorporeal treatments with protein A (Prosorba) columns in the treatment of patients with severe refractory rheumatoid arthritis (RA) in an open label pilot study.

Fifteen patients with RA who had failed to respond to 2 or more disease modifying antirheumatic drugs were "washed out" for 1-3 months before enrollment into this 6 month pilot study. The treatment schedule called for patients to receive apheresis treatments across staphylococcal protein A columns once a week for 12 weeks. Clinical evaluations of RA activity, defined by Paulus criteria, were conducted at study enrollment (baseline) and monthly throughout the treatment phase. In addition, examinations were conducted at 2, 4, 8, and 12 weeks after the last treatment. Fourteen patients received all 12 scheduled treatments, while one patient received only 10 treatments due to complications secondary to pneumonia.

Using Paulus 50% criteria, 9 of 15 (60%) patients were improved at the 4th month, and one more fulfilled >20% Paulus criteria (7%) in the 5th month after starting therapy. The study group reported an average of 2.47 adverse effects per treatment, of which the most common were joint pain and swelling and fatigue of short duration (arthritic flare).

The adverse effects associated with this apheresis based treatment proved to be manageable and of short duration and resolved without sequelae. The results suggest that extracorporeal protein A therapy may have a role in the management of refractory RA, and encouraged the initiation of a larger, blinded, controlled clinical trial.