Review of ibandronate in the treatment of metastatic bone disease: experience from phase III trials.

BACKGROUND: Metastatic bone disease is a serious clinical problem in patients with advanced cancer. Bisphosphonates inhibit the activity of osteoclasts and are the treatment of choice for bone metastases.

OBJECTIVE: This article reviews the efficacy and safety data from Phase III trials of ibandronate in metastatic bone disease.

METHODS: Phase III data (available as of June 2004) for ibandronate were reviewed. Literature searches using the MEDLINE database and abstracts from scientific meetings were used to obtain data from Phase III trials of ibandronate.

RESULTS: Compared with placebo, patients with bone metastases from breast cancer receiving IV ibandronate (6 mg infused over 1-2 hours every 3-4 weeks) or oral ibandronate (50 mg/d for up to 96 weeks) had a statistically significant reduction in skeletal complications, as measured by the Skeletal Morbidity Period Rate (P = 0.004 vs placebo). Multivariate Poisson regression analysis of the data showed that the risk of a new bone event was reduced by 40% with IV ibandronate 6 mg and by 38% with oral ibandronate 50 mg, compared with placebo (P < or = 0.003). Both formulations also reduced bone pain below baseline levels over 2 years (P < or = 0.001 vs placebo). IV and oral ibandronate were well tolerated, with adverse-event profiles comparable to placebo and no significant renal toxicity.

CONCLUSIONS: IV and oral ibandronate provide meaningful clinical benefits in patients with bone metastases from breast cancer. Both formulations reduce the risk of skeletal events and provide sustained relief from metastatic bone pain. With its favorable efficacy and safety profile, and the added convenience of the oral formulation, ibandronate provides improved treatment options for managing metastatic bone disease.