Bisphosphonate treatment recommendations for oncologists.

Renal safety is an important consideration for oncologists who are treating patients with bisphosphonates. In recent years, there has been increasing awareness about the development of bisphosphonate-induced nephrotoxicity. This has emerged mainly from increased clinical experience with zoledronic acid (Zometa); Novartis Pharmaceuticals Corporation, East Hanover, NJ, http://www.pharma.us.novartis.com). For this reason, the U.S. and European product labels for i.v. zoledronic acid were recently updated to include additional renal safety cautions, including dose adjustment in patients with mild-to-moderate renal impairment. However, renal toxicity is not a class effect. The product label for ibandronate (Bondronat), F. Hoffmann-La Roche Ltd., Basel, Switzerland, http://www.roche.com) has remained unchanged since the launch of the drug in the European Union in 2003. Ibandronate does not require mandatory monitoring of kidney function prior to each infusion. In addition, ibandronate can be used in patients with varying degrees of renal impairment. It also can be used without restrictions for nephrotoxic medications, and dose adjustment is only required in patients with severe renal impairment. Clinical implications of the renal safety of ibandronate include reducing the physician and nursing time needed for managing the adverse renal events associated with bisphosphonate therapy and dosing based on renal function. There also are no added renal safety risks and fewer inconvenient hospital visits with ibandronate therapy. In addition to i.v. ibandronate, an oral formulation of the drug is available. Oral ibandronate therapy is especially desirable because the medication is convenient (with a small, once-daily tablet that can be taken at home), reducing the health care costs associated with infusions. Clinical studies also indicate that 50 mg oral ibandronate has an efficacy similar to that of i.v. bisphosphonates and is associated with a low incidence of adverse gastrointestinal events.