Effect of pamidronate administration on markers of bone turnover and disease activity in multiple myeloma

Aim: Bisphosphonates are potent inhibitors of osteoclastic activity and are used in the treatment of multiple myeloma (MM) in combination with chemoth erapy. The effect of pamidronate on markers of bone resorption [cross-linke d N-telopeptides of type I collagen (NTx)] markers of bone formation [serum alkaline phosphatase (BAP) and osteocalcin (OSC)], interleukin-6 (IL-6), b eta (2)-microglobulin, CRP, paraprotein and disease-related pain and skelet al events has been evaluated in 62 newly diagnosed patients with MM. Patien ts and methods: The patients were randomly assigned to two groups: the firs t included 32 patients under chemotherapy and pamidronate (group I) and the second 30 patients on chemotherapy only (group II). Pamidronate was admini stered at a monthly dose of 90 mg iv, and the above parameters were evaluat ed at the beginning of this study and after 1, 3, 6, 9, 12 and 14 months of treatment. Results: The addition of pamidronate to chemotherapy resulted i n a significant reduction of NTx, IL-6 and paraprotein from the 3rd month a nd of beta (2)-microglobulin, CRP and pain from the 6th month of treatment. No changes of NTx, IL-6, beta2-microglobulin, CRP or skeletal events were observed in patients of group II, while paraprotein was significantly reduc ed after 6 months of treatment. The differences in NTx, IL-6, paraprotein a nd beta (2)-microglobulin were statistically significant between the two gr oups. Multivariate analysis revealed a significant correlation between chan ges of NTx, changes of IL-6 in both groups and reduction of pain and parapr otein in group I. Conclusions: These results suggest that pamidronate may h ave a synergistic action with chemotherapy in decreasing osteoclastic activ ity, in reducing markers of myeloma activity and myeloma related pain and i n improving the quality of life in patients with MM.