Preventing bone loss during androgen deprivation therapy for prostate cancer: Early experience with neridronate

Objective: Androgen-deprivation therapy (ADT) is the usual treatment for locally advanced or metastatic prostate cancer. Osteoporosis is a common complication of ADT. The aim of our study was to evaluate the efficacy of neridronate, a relatively new bisphosphonate to prevent bone loss during androgen ablation. Methods: Sixty patients with prostate cancer and osteoporosis were enrolled and randomly assigned to 2 different treatment regimes: group A (30 patients) treated with maximum androgenic blockage (MAB), and group B (30 patients) treated with bicalutamide 150 mg. Each group was divided in 2 subgroups A1-A2 and B1-B2. All patients received calcium and cholecalciferol supplements (500 mg of elemental calcium and 400 IU cholecalciferol) daily. The A2 and 132 subgroups were also treated with neridronate (25 mg intramuscular monthly). Lumbar and femoral bone mineral density (BMD) was evaluated by dualenergy X-ray absorptiometry (DXA), both at baseline and after one year of treatment. Deoxypyridinoline (DPD) and bone-alkaline phosphatase (B-ALP) were determined at the beginning, midstudy and at the end. Results: Patients treated only with calcium and cholecalciferol (A1, B1 subgroups) showed a marked bone loss after 6, and 12 months, with increased levels of DPD and BALP, compared to baseline values. Patients treated with neridronate (A2 et B2 subgroups) showed unchanged levels of these markers. After one year of treatment, lumbar and total hip BMD decreased significantly in patients treated only with calcium and cholecalciferol (A1 subgroup: -4.9% and -1.9% respectively). BMD did not change significantly at any site in patients treated also with neridronate (A2 subgroup: +1% and +0.8% respectively). Lumbar and total hip BMD did not change significantly (-1.5% and -1% respectively) in B 1 subgroup. In 132 subgroup an important increase in lumbar spine and the total hip BMD was shown (+2.5% and 1.6% respectively). No relevant side effects were recorded during our study. Conclusion: In conclusion, neridronate is an effective and safe treatment in preventing bone loss in men receiving ADT for prostate cancer