Possible Link Between Bisphosphonates, Esophageal Cancer Sparks FDA Review

Studies Examined to Date Show Conflicting Data

August 01, 2011 05:25 pm News Staff

The FDA once again is examining safety data related to the use of bisphosphonates. This time, the agency is reviewing conflicting reports regarding oral bisphosphonates and the risk for esophageal cancer.

Although the agency said in a July 21 safety announcement(www.fda.gov) that its safety review is ongoing, at this time, the benefits the osteoporosis drugs provide in reducing the risk of serious fractures continue to outweigh the potential risks.

The largest studies the FDA has reviewed to date are two epidemiologic studies that used the same patient database -- the United Kingdom's General Practice Research Database -- but arrived at quite different conclusions. Although one of these studies(jama.ama-assn.org) found no increase in the risk of esophageal cancer with oral bisphosphonate use, the second study(www.bmj.com) found a doubling of the esophageal cancer risk among patients who had 10 or more prescriptions for the drugs or who had taken them for more than three years.

Story Highlights

  • The FDA is reviewing safety data on oral bisphosphonates and an elevated risk for esophageal cancer associated with their use.
  • Two studies on this risk that used the same database produced conflicting results.
  • At this time, says the FDA, the benefits of bisphosphonates in reducing the incidence of serious fractures in people with osteoporosis continue to outweigh the risks.
  • there are insufficient data to recommend endoscopic screening of asymptomatic patients;
  • esophagitis and other esophageal events have been reported, particularly in patients who do not follow the specific directions for use of oral bisphosphonates; and
  • patients should be instructed to carefully follow the directions for use of the drugs. Oral bisphosphonates -- with the exception of risedronate delayed-release, which is marketed as Atelvia -- should be taken with a full glass of plain water just after awakening in the morning. Risedronate delayed-release should be taken immediately after breakfast. Patients should not lie down or eat or drink anything for at least 30-60 minutes after taking any oral bisphosphonate.

Other drugs in the class are alendronate, which is marketed as Fosamax; ibandronate, which is marketed as Boniva; etidronate, which is marketed as Didronel; risedronate, which is marketed as Actonel; and tiludronate, which is marketed as Skelid.

The FDA previously reviewed safety data related to nonserious atrial fibrillation with bisphosphonate use, but the agency found no clear association. Last year, the agency alerted physicians to the risk of atypical fractures of the femur in patients taking bisphosphonates.

Physicians are encouraged to report adverse events involving bisphosphonate drugs to the FDA's MedWatch program(www.accessdata.fda.gov).