Immunopharmacological evaluation of bucillamine in rheumatoid arthritis.

Seventy six patients with rheumatoid arthritis (RA) treated with bucillamine, a novel immunomodulating drug with no antiinflammatory effects, were evaluated in terms of the immunomodulating effects. Clinical symptoms and laboratory data, including lymphocyte subset changes, were followed for 12 or more months. Long-term administration of bucillamine markedly improved arthritis and suppressed the titre of rheumatoid arthritis haemagglutination. Flow cytometric analysis of peripheral blood T cell subsets showed that bucillamine induced a characteristic increase in the cell constituent ratio of CD4+CD45RA+ T cells. Decreases in CD4+CD45RO+ T cells, CD8+HLA-DR+ T cells and CD5+ B cells were considered characteristic features induced by bucillamine administration.