We are aware of a recent Food and Drug Administration (FDA) publication that reports on the association between use of zoledronic acid (Aclasta) and renal impairment. 1

We recognize that you might find this report concerning and it may raise questions about your care. Osteoporosis Canada takes your concerns seriously and we will continue to be vigilant in order to inform you about the latest research. The publication has been reviewed by experts from the Scientific Advisory Committee at Osteoporosis Canada and their response is below.

From April 2007 until February 17, 2009 the FDA’s Adverse Event Reporting System received reports of 24 cases of renal impairment and some cases of renal failure associated with the use of zoledronic acid. Over half of the patients had underlying medical conditions such as diabetes, heart failure or chronic kidney disease that might have contributed to the renal failure; or were taking medication that could be damaging to the kidney. Fifty four percent of patients who developed renal disease had increases in serum creatinine after administration of zoledronic acid. Most patients improved after intravenous fluid administration or other supportive care.

It is important to note that all of the FDA reports occurred in patients at risk of developing renal dysfunction– those with underlying moderate to severe renal impairment or other risk factors including use of nephrotoxic medications, diuretic therapy, or severe dehydration. Physicians are encouraged to avoid the use of zoledronic acid in patients with severe renal impairment (creatinine clearance of <35 mL/min); monitor serum creatinine before each dose of zoledronic acid; consider interim monitoring of serum creatinine in at risk patients; assure that patients are adequately hydrated prior to administration of zoledronic acid; and to infuse zoledronic acid over a period of at least 15 minutes.

It is a fact – all medications have risks associated with them. Osteoporosis medications are no exception. Every time a physician recommends and prescribes a medication, it includes carefully weighing the risks and benefits of taking a medication. While the reports on the association between zoledronic acid and renal failure are concerning this happens very rarely.

Fractures (broken bones) due to osteoporosis, on the other hand, are extremely common. Osteoporotic fractures are linked to additional fractures, altered quality of life, worsening of other health conditions and in some cases – death. Bisphosphonate medications, such as zoledronic acid provide protection from osteoporotic fractures. Your healthcare team is available to review any concerns or questions you may have about this issue.

1. http://www.fda.gov/downloads/Drugs/DrugSafety/DrugSafetyNewsletter/UCM168579.pdf