Comparison of Zometa Retention and Effect in Multiple Myeloma and Breast Cancer

The clinical benefit from treatment with bisphosphonates has been documented in a large number of clinical studies, and bisphosphonates are now widely used for treatment of pain and prevention of bone fractures or vertebral collapse for example in patients with cancer metastasis to bone or multiple myeloma.

Repeated intravenous administration of the more potent bisphosphonates (pamidronate and zoledronic acid) are often used for treatment of osteolytic disease caused by disseminated cancer or multiple myeloma, while the less potent oral bisphosphonates are often prescribed for treatment of benign osteoporosis. The recommended dose and time schedule for treatment with the more potent bisphosphonates is based on concerns of avoiding toxicity and at the same time obtaining maximal clinical benefit. Clinical studies in multiple myeloma and bone metastasis show significant activity of pamidronate (90 mg by iv infusion during 2-4 hours) or zoledronic acid (4 mg iv during 15 min) repeated every 4 weeks after a treatment period of 9 months and beyond, but the optimal duration of treatment is not known. This is a particular important issue since the use of potent bisphosphonates have been brought in connection with osteonecrosis.

In the present study we will compare the retention of Zometa with the effect on bone markers in patients with multiple myeloma or breast cancer with metastases to bone.