A prospective, controlled, nonrandomized study on prophylactic parenteral dichloromethylene bisphosphonate (clodronate) in multiple-myeloma.

Bone resorption by osteoclasts causes neoplastic bone disease, which is a significant cause of death in multiple myeloma (MM). Counteracting bone resorption with prophylactic bisphosphonates has delayed bane disease, and this is expected to improve survival. Between January, 1987 and March, 1990, 341 evaluable previously untreated, consecutive patients with MM entered a prospective, multicenter study in which cytostatic therapy was randomized. The first 148 patients recruited were not planned for prophylaxis and the following 193 were scheduled to receive parenteral, prophylactic clodronate. Clodronate was administered at a dose of 600-1000 mg/4-6 weeks and was started at diagnosis and continued throughout survival time. Data on clodronate prophylaxis were evaluated on both an intention-to-treat and a compliance analysis basis. The rate of response and the duration of response were independent of clodronate prophylaxis. Progression of skeletal disease occurred less often in patients who received the drug than in those who were not given prophylaxis (50.5 vs 34.8%; p<.02 by compliance analysis). Survival was longer for patients on clodronate prophylaxis than for those who were not planned for (p<.02 by intention to-treat-analysis) or for those who did not receive clodronate prophylaxis (p<.009 by compliance analysis). Local pain associated with i.m. administration was the only significant side effect of clodronate. Parenteral clodronate prophylaxis prolongs survival in MM, probably because it allows better control of bone disease and reduces deaths related to it