Study: Fosamax Linked to Increased Risk of Esophageal Cancer

Philadelphia, PAA new study suggests that Fosamax side effects could include a risk of esophageal cancer. Fosamax lawsuits allege the drug is linked to an increased risk of osteonecrosis of the jaw and atypical femur fractures, although Merck, maker of Fosamax, has won all but one of the Fosamax osteonecrosis of the jaw lawsuits.

The most recent Fosamax study, presented to the American Society of Clinical Oncology 2012 annual meeting (abstract found online at asco.org), examined the link between the use of bisphosphonates—a class of drug that includes Fosamax—and the development of esophageal cancer. According to the study's authors, led by Beatrice Edwards, in 2009, the US Food and Drug Administration (FDA) reported 23 patients who developed esophageal cancer within two years of starting alendronate (the generic of Fosamax) therapy, while 31 cases were identified in Europe and Japan.

Researchers examined the FDA's Adverse Event Reporting System (AERS) to determine if the use of bisphosphonate medications was linked to an increased risk of esophageal cancer. They found 128 cases of esophageal cancer that were associated with bisphosphonate use, including 96 involving alendronate.

"Our analysis of FDA AERS identifies a larger number of cases of esophageal cancer than previously described, and a significant safety signal with alendronate use," researchers wrote. They recommended that bisphosphonates not be used in patients with Barrett's esophagus or persistent mucosal abnormalities.

Fosamax is used to prevent osteoporosis but lawsuits filed against Merck allege the drug is linked to serious conditions, including osteonecrosis of the jaw (jawbone death). Meanwhile, a study published in the Archives of Internal Medicine (5/21/12), suggests that biosphosphonates are linked to atypical femur fractures. The study found that patients who used bisphosphonate medications were more likely to suffer broken legs. Researchers further found that of the 39 patients treated at a Geneva hospital for a broken leg linked to virtually no trauma, 32 patients had taken a bisphosphonate. Furthermore, of those 32 patients, seven suffered an atypical fracture in both legs.

Merck has already faced multiple lawsuits concerning Fosamax, with the drugmaker winning all but one of the bellwether trials.