This single arm study will assess the efficacy of loading doses of intravenous Bondronat in reducing pain in patients with breast cancer and metastatic bone disease experiencing moderate to severe bone pain. Patients will receive an intravenous infusion of 6mg Bondronat on days 1, 2 and 3. The anticipated time on study treatment is <3 months, and the target sample size is <100 individuals.

Inclusion Criteria:

• adult patients, >=18 years of age;
• breast cancer;
• bone metastases;
• mean worst pain score >=4 during 3 day baseline period;
• stable dose of analgesics over a 3 day baseline period;
• adequate renal function.

Exclusion Criteria:

• bisphosphonate treatment within 3 weeks of study enrollment;
• a change in antineoplastic treatment within 6 weeks of study enrollment;
• bone radiation within 2 weeks of study enrollment;
• active infection.