This study will evaluate renal function in participants with metastatic bone disease due to breast cancer receiving intravenous (IV) infusions of ibandronate (Bondronat) 6 milligrams (mg), over either 15 minutes or 60 minutes, every 3 weeks. Efficacy and safety of ibandronate in the 2 groups of participants will also be compared. The anticipated time on study treatment is 7 months, and the target sample size is 318 individuals.

Inclusion Criteria:

• For participants of childbearing potential: negative pregnancy test and ready to use effective contraceptive measures
• Metastatic breast cancer with at least one bone metastasis
• Karnofsky index >/= 60
• Life expectancy >/= 6 months
• Estimated creatinine clearance (Cockcroft and Gault formula) >/= 30 milliliters per minute (mL/min)

Exclusion Criteria:

• Pregnancy or breast feeding participant
• Participant who had a current dental problem, particularly tooth or jaw infection, trauma or surgery on tooth or jaw in the previous six weeks, medical history of jaw osteonecrosis or delayed healing after dental surgery
• Participant who was participating or had participated in the last 30 days to a clinical trial investigating treatments
• Uncontrolled brain metastasis
• Severe or concomitant infection
• Known medical history of systemic disease with renal lesion
• Rapidly progressing renal failure at inclusion
• Uncontrolled cardiac disorder
• Hypercalcaemia (> 2.7 millimoles per liter [mmol/L]), hypocalcaemia (< 2 mmol/L)
• Participant receiving nephrotoxic chemotherapy
• Participant eligible for haematopoietic stem cell transplantation at inclusion time
• Bisphosphonate therapy in the 3 weeks before randomization
• Known hypersensitivity to ibandronate or other bisphosphonates