PAGET'S BONE DISEASE: RESPONSE TO HUMAN CALCITONIN IN PATIENTS RESISTANT TO SALMON CALCITONIN

Abstract

Abstract Of 27 patients (2 with osteoporosis, 25 with Paget's bone disease) treated with salmon calcitonin (S.C.T.) for 10 to 43 months, serum antibodies to S.C.T. were detected in both patients with osteoporosis and in 10 patients with Paget's disease. Human calcitonin (H.C.T.) was available to treat the Paget's disease in 5 of the patients who had demonstrable serum antibodies to S.C.T., and rebound elevations of serum-alkaline-phosphatase and urinary hydroxyproline. Maximum serum-binding capacities for S.C.T. ranged from 2 to 541 μg. per litre. All patients showed a hypocalcaemic response to the acute subcutaneous administration of 0·5 mg. of H.C.T., but only the 2 patients with low serum S.C.T. antibody titres responded to a comparable biological dose of S.C.T. All 5 patients showed significant biochemical improvement during the first 2-3 months of treatment with H.C.T., with reduction of serum-alkaline-phosphatase to 33-50% of pretreatment levels. Human calcitonin can be used successfully to treat patients who are resistant to foreign calcitonins.