The warning is targeted at patients who already suffer from kidney impairment. It's also aimed at those who are taking potentially kidney-damaging (nephrotoxic) medications or diuretics at the same time as Reclast.
According to the new warning, Reclast-induced kidney failure can also occur among severely dehydrated patients. Older patients with kidney impairment are at heightened risk of kidney failure.
The FDA warning says that kidney failure is a rare but serious complication for at-risk patients taking Reclast. The drug was approved in April 2007.
Two dozen cases of kidney impairment or failure, including five deaths, were reported in a safety review published in January 2009. That led the FDA to recommend monitoring serum creatinine -- a measure of kidney health -- before each dose of the injected medication.
By April 2011, there were 11 more Reclast-related deaths due to kidney failure. Nine cases of kidney injury were also reported. Each required dialysis.
How Reclast Is Used
Reclast is manufactured by Novartis. It is prescribed to treat or prevent osteoporosis among postmenopausal women. In those women the drug reduces the risk of hip and spinal fractures.
Reclast is administered in infusions every one to two years. It may be used to bolster bone mass in men with osteoporosis. The drug is prescribed for men and women who take corticosteroid drugs for at least one year to prevent osteoporosis. It is also prescribed for people with a bone-weakening condition known as Paget's disease of bone.
The new warning tells doctors and patients the following:
- Do not to prescribe Reclast to patients with creatinine clearance less than 35 mL/min or to those with evidence of acute kidney impairment.
- Patients should be monitored before taking the drug for underlying kidney impairment as well as for dehydration.
- Underlying kidney disease and dehydration caused by fever, sepsis, gastrointestinal losses, diuretic medications, and other factors may raise the risk of acute renal failure.
- Creatinine clearance should be calculated before each dose of Reclast. It should also be monitored between doses in at-risk patients.
- Any adverse events should be reported to the FDA's MedWatch program.
The warning also offers the following advice to patients:
- Kidney failure is a serious but rare side effect of Reclast.
- Your kidney function will be assessed before and after being given a Reclast infusion.
- Medications other than Reclast may be more suitable for you if you have kidney problems. Discuss your options with your doctor.
- Your doctor should be aware of all medications that you are currently taking. Keep a list with you so that you can easily share it with your doctor.
Zoledronic acid is also marketed under the name Zometa for the treatment of cancer-related bone damage. Zometa's label already contains warnings regarding kidney toxicity.