CLINICAL AND BIOCHEMICAL RESPONSE TO SINGLE INFUSION OF PAMIDRONATE IN PATIENTS WITH ACTIVE RHEUMATOID-ARTHRITIS - A DOUBLE-BLIND PLACEBO-CONTROLLED STUDY

Objective. To assess the effects of 3-amino-1-hydroxypropylidine-1,1-b isphosphonate (pamidronate) in rheumatoid arthritis (RA). Methods. Thi rty patients with active RA were randomly allocated to receive a singl e intravenous infusion of placebo, 20 mg pamidronate, or 40 mg pamidro nate. Results. Pamidronate treatment resulted in a rapid and sustained reduction in urinary calcium and hydroxyproline excretions. A sustain ed reduction in serum corrected calcium was only noted in the group tr eated with 40 mg pamidronate. In both groups treated with pamidronate a temporary increase in serum parathyroid hormone was noted. Compared to the placebo group clinical variables of disease activity improved s ignificantly in both groups treated with aminohydroxypropylidine bisph osphonate. The erythrocyte sedimentation rate and serum C-reactive pro tein levels improved significantly in patients treated with 40 mg pami dronate. No serious side effects were documented. Conclusion. A single infusion of pamidronate in patients with RA is safe, suppresses bone resorption, and reduces disease activity. It is suggested that the eff ect on disease activity is dose dependent.