Bisphosphonates are widely used to treat osteoporosis and to slow bone turnover in patients with Paget's disease of the bone and to treat some cancer patients.
Doctors shouldn't alter their prescribing patterns for bisphosphonates and patients should keep taking their bisphosphonates, according to the FDA.
There are seven FDA-approved bisphosphonates:
- alendronate (sold generically and as Fosamax)
- ibandronate (sold as Boniva)
- risedronate (sold as Actonel)
- zoledronic acid (sold as Reclast and Zometa)
- etidronate (sold as Didronel)
- pamidronate (sold generically and as Aredia)
- tiludronate (sold as Skelid)
The FDA has been looking into a possible association between bisphosphonates and an irregular heart rhythm (atrial fibrillation) since October 2007.
The FDA today stated that, based on the evidence it has reviewed thus far, there is "no clear association between overall bisphosphonate exposure and the rate of serious or nonserious atrial fibrillation."
That finding is based on data from studies of more than 19,000 patients who took bisphosphonates and more than 18,000 other patients who took placebos for up to three years. Atrial fibrillation was "rare within each study, with most studies containing two or fewer events," the FDA states.
The FDA acknowledges mixed results in other studies of atrial fibrillation in patients taking bisphosphonates, and the FDA hasn't ruled out further studies. The FDA will also keep monitoring reports of atrial fibrillation in patients taking bisphosphonates.